Sample records for zone southern chile

  1. Thermal and climatic zoning for construction in the southern part of Chile

    NASA Astrophysics Data System (ADS)

    Verichev, Konstantin; Salimova, Alisa; Carpio, Manuel

    2018-05-01

    This paper presents the results of the updated boundaries of thermal zones in the tree southern regions of Chile, based on the method of heating degrees-days according to hourly temperature measurements at meteorological stations in the last decade. The Ministry of Housing and Urban Planning of Chile has not updated these boundaries since 1999. Using the Climatic Severity index method, the relative energy consumption of dwellings was analyzed for cooling and heating in summer and winter periods, respectively. The analysis revealed that, within the limits of a single thermal zone, the energy costs for cooling in the summer period of the same house may differ by 50 %.

  2. Tephrochronology of the southernmost Andean Southern Volcanic Zone, Chile

    NASA Astrophysics Data System (ADS)

    Weller, D. J.; Miranda, C. G.; Moreno, P. I.; Villa-Martínez, R.; Stern, C. R.

    2015-12-01

    Correlations among and identification of the source volcanoes for over 60 Late Glacial and Holocene tephras preserved in eight lacustrine sediment cores taken from small lakes near Coyhaique, Chile (46° S), were made based on the stratigraphic position of the tephra in the cores, lithostratigraphic data (tephra layer thickness and grain size), and tephra petrochemistry (glass color and morphology, phenocryst phases, and bulk-tephra trace element contents determined by ICP-MS). The cores preserve a record of explosive eruptions, since ˜17,800 calibrated years before present (cal years BP), of the volcanoes of the southernmost Andean Southern Volcanic Zone (SSVZ). The suggested source volcanoes for 55 of these tephras include Hudson (32 events), Mentolat (10 events), and either Macá or Cay or some of the many minor monogenetic eruptive centers (MECs; 13 events) in the area. Only four of these eruptions had been previously identified in tephra outcrops in the region, indicating the value of lake cores for identifying smaller eruptions in tephrochronologic studies. The tephra records preserved in these lake cores, combined with those in marine cores, which extend these records back to 20,000 cal years BP, prior to the Last Glacial Maximum, suggest that no significant temporal change in the frequency of explosive eruptions was associated with deglaciation. Over this time period, Hudson volcano, one of the largest and longest lived volcanoes in the Southern Andes, has had >55 eruptions (four of them were very large) and has produced >45 km3 of pyroclastic material, making it also one of the most active volcanoes in the SVZ in terms of both frequency and volume of explosive eruptions.

  3. The TIPTEQ seismological network in Southern Chile - Studying the Seismogenic Coupling Zone

    NASA Astrophysics Data System (ADS)

    Haberland, C.; Rietbrock, A.; Lange, D.; Bataille, K.; Hofmann, S.; Dahm, T.; Scherbaum, F.; Tilman, F.; Hermosilla, G.; Group, T. S.

    2005-12-01

    Subduction zones generate the world's largest and most destructive earthquakes. Understanding the factors leading to these earthquakes in the coupling zone of convergent margins and their interrelation with surface deformation are the main aims of the international and interdisciplinary research initiative TIPTEQ (From The Incoming Plate To megaThrust EarthQuake Processes) which is financed by the German Ministry for Education and Research (BMBF). These aims shall be achieved by obtaining high resolution images of the seismogenic zone and the forearc structure, which will form the base for identifying the processes involved. Our studies focus spatially on the nucleation zone of the Mw=9.5 1960 Chile earthquake, the worldwide largest instrumentally ever recorded earthquake. Within this project a large temporary seismological network is installed in southern Chile since Nov. 2004, covering the forearc between 37° and 39°S. It consists of 120 digitally recording and continuously running seismic stations equipped with short period sensors. The network covers the forearc between 37° and 39°S. The onshore network is complemented by 10 ocean bottom seismometers/hydrophones (OBS/OBH), and the stations (except for 20 stations which will operate until October 2005) were in operation until July 2005. The network is characterized by very short station spacings in the centre which will assure an increased quantity of P and S phase onset times and which will achieve the observation of the whole wavefield (coherent waveforms). A second network of 20 onshore and 20 offshore stations is installed at and around Chiloe Island for a one year period. Until now we collected about 1.2 TByte of data. First steps of the data processing are the event detection, the onset time picking, and the localisation of the (local) earthquakes (catalog). Later steps include the determination of the velocity and attenuation structure (tomography), the analysis of the stress field by moment tensor

  4. Epidemiological description of the sea lice (Caligus rogercresseyi) situation in southern Chile in August 2007.

    PubMed

    Hamilton-West, Christopher; Arriagada, Gabriel; Yatabe, Tadaishi; Valdés, Pablo; Hervé-Claude, Luis Pablo; Urcelay, Santiago

    2012-05-01

    Salmon sea lice represent one of the most important threats to salmon farming throughout the world. Results of private monitoring efforts have shown an increase in the number of positive cages and cage-level abundance of sea lice in southern Chile since 2004. As a consequence, the Chilean Fisheries Service implemented an Official Surveillance Program in the main salmon production area of southern Chile to assess the situation of sea lice in fish farms. Results showed that the prevalence of sea lice in the fish farms was 53.4%, ranging from 3.5% in Puerto Aysén to 100% in the Seno de Reloncaví zone. The average sea lice abundance was 11.8 per fish (Geometrical mean (GM)=8.61, 95% CI (2.1-6.9)). The highest levels were found in Seno de Reloncaví (GM=24.99, 95% CI (15.9-39.2)), Hornopirén (GM=14.7, 95% CI (10.4-20.8)) and Chiloé norte (GM=9.75, 95% CI (1-1.9)), and the lowest loads were observed in Puerto Aysén (GM=1.35, 95%CI (1-1.9)) and Puerto Cisnes (GM=1.67, 95%CI (1.1-2.6)). Salmo salar and Oncorhynchus mykiss had the highest abundance levels (GM=6.93, 95% CI (5.7-8.5), and (GM=5.55, 95% CI (3.6-8.5), respectively). O. kisutch showed lower levels (GM=1.34, 95% CI (1-1.7)), apparently being more resistant to infestation. Sea lice in farmed salmon are widely distributed in different zones of southern Chile, and are becoming a serious threat to this industry. Prevalence and abundance levels were found to be generally high, decreasing in southern zones. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. The Aysen (Southern Chile) 2007 Seismic Swarm: Volcanic or Tectonic Origin?

    NASA Astrophysics Data System (ADS)

    Comte, D.; Gallego, A.; Russo, R.; Mocanu, V.; Murdie, R.; Vandecar, J.

    2007-05-01

    The Aysen seismic swarm began January 23, 2007, with a magnitude 5.2 (USGS) earthquake and, after an apparent decrease in activity, continued with a magnitude 5.6 event on February 26. The swarm is characterized by numerous felt earthquakes of small to moderate magnitude, located at crustal depths beneath the Aysen Canal, a prominent fiord of the Chilean littoral. The region is characterized by the subduction of an active oceanic spreading ridge: the Chile Ridge, the divergent Nazca-Antarctic plate boundary, is currently subducting beneath continental South America along the Chile Trench at approximately 46.5°S, forming a plate triple junction in the vicinity of the Taitao Peninsula, somewhat south and west of the swarm. Also, the Liquine-Ofqui dextral strike- slip fault traverses the Aysen Canal in the vicinity of the swarm. This fault has been interpreted as a 1000 km long dextral intra-arc strike-slip fault zone, consisting of two major strands which extend north from the Chile Margin triple junction. The Liquiñe-Ofqui system is marked by several pull-apart basins along its trace through the area. Seismic activity along the Liquiñe-Ofqui fault zone has been poorly studied to date, largely because teleseismic events clearly related to the fault have been few, and southern hemisphere seismic stations are lacking. However, we deployed a dense temporary broad-band seismic network both onland and on the islands in the Aysen region, which allowed us to capture the initial phases of the swarm on some 20 stations, and to determine the background seismicity patterns in this area for the two years preceding the swarm. The swarm could be caused by several processes: the spatial and depth distribution of the events suggests that they are well correlated with reactivation of the southern end of the Liquiñe-Ofqui fault, as defined by geologic studies and onshore gravity data collected in southern Chile. The swarm may be related to formation of new volcanic center between

  6. Finite-fault slip model of the 2016 Mw 7.5 Chiloé earthquake, southern Chile, estimated from Sentinel-1 data

    NASA Astrophysics Data System (ADS)

    Xu, Wenbin

    2017-05-01

    Subduction earthquakes have been widely studied in the Chilean subduction zone, but earthquakes occurring in its southern part have attracted less research interest primarily due to its lower rate of seismic activity. Here I use Sentinel-1 interferometric synthetic aperture radar (InSAR) data and range offset measurements to generate coseismic crustal deformation maps of the 2016 Mw 7.5 Chiloé earthquake in southern Chile. I find a concentrated crustal deformation with ground displacement of approximately 50 cm in the southern part of the Chiloé island. The best fitting fault model shows a pure thrust-fault motion on a shallow dipping plane orienting 4° NNE. The InSAR-determined moment is 2.4 × 1020 Nm with a shear modulus of 30 GPa, equivalent to Mw 7.56, which is slightly lower than the seismic moment. The model shows that the slip did not reach the trench, and it reruptured part of the fault that ruptured in the 1960 Mw 9.5 earthquake. The 2016 event has only released a small portion of the accumulated strain energy on the 1960 rupture zone, suggesting that the seismic hazard of future great earthquakes in southern Chile is high.

  7. Calbuco Volcano Erupts in Southern Chile

    NASA Image and Video Library

    2015-04-24

    Calbuco Volcano in southern Chile has erupted for the first time since 1972, with the last major eruption occurring in 1961 that sent ash columns 12-15 kilometers high. This image was taken by the Suomi NPP satellite's VIIRS instrument in a high resolution infrared channel around 0515Z on April 23, 2015. Credit: NOAA/NASA/NPP/VIIRS

  8. Metazoan parasites of Brama australis from southern Chile: a tool for stock discrimination?

    PubMed

    Oliva, M E; Espinola, J F; Ñacari, L A

    2016-03-01

    The metazoan parasites of 403 specimens of the southern ray's bream Brama australis from three localities in southern Chile (Lebu 36° 70' S; 73° 40' W, Calbuco 41° 50' S; 73° 08' W and Punta Arenas 53° 10' S; 70° 50' W) were recorded. More than 23 400 parasite specimens belonging to 12 taxa were registered. Metazoan parasites were dominated by the copepod Hatschekia conifera, constituting 97% of the total number of parasites; the larval cestode Hepatoxylon trichiuri was the second most important parasite (2·1% of the total number of parasites). The remaining 10 species constituted <1% of the metazoan parasites. Parasitological evidence, based on univariate and multivariate analysis, does not support the existence of discrete stocks in the studied zone. © 2016 The Fisheries Society of the British Isles.

  9. New records for millipedes from southern Chile (Polydesmida: Dalodesmidae; Polyzoniida: Siphonotidae).

    PubMed

    Mesibov, Robert Evan

    2017-01-01

    Millipedes from 1983 collections by the author in southern Chile have been identified and registered as specimen lots at the Queen Victoria Museum and Art Gallery (QVMAG) in Launceston, Tasmania. Collection and specimen data from the new QVMAG specimen lots have been archived in Darwin Core format together with a KML file of occurrences. The 31 occurrence records in the Darwin Core Archive list 13 millipede taxa from 16 sites in Llanquihue and Osorno provinces, Chile.

  10. Hydrodynamics of the 1868 and 1877 tsunamis in Southern Peru and Northern Chile

    NASA Astrophysics Data System (ADS)

    Morales, S.; Soto-Sandoval, J.; Monardez, P.

    2013-05-01

    The tsunami occurred on 27th February 2010 offshore central Chile due to a mega-thrust earthquake (Mw=8.8), showed a complex hydrodynamic behavior in the near field that is not completely understood and could not be well characterized using linear models (Cox 2011, Fujima 2011). Several floods separated by several minutes that lasted over eight hours, which flowed parallel to the coast were reported. A reasonable physical explication for this phenomena has been published. Due to the distance from the rupture zone to the coast is shorter than a complete tsunami wave, the latter cannot be created then secondary effects are triggered (Monárdez and Salinas, 2011). This was validated using numerical models based on RANS equations and measurements and field observations in the 2010 Chilean tsunami. Due to this knowledge, the 1868 and 1877 last mega-thrust earthquakes in the Southern Peru and Northern Chile are analyzed. This became necessary, since this zone is known as one the major seismic gap in the area. Scenarios with different fault parameters were implemented for the 1868 and 1877 tsunamis and important results were obtained. In both of the tsunamis, several floods were observed and the arrival time and direction of flow propagation were according to historical reports. In the 1868 tsunami, the effects on the Chilean coast are due to secondary effects such as it is described in historical observations, e.g. in Arica port three main floods 40, 120 and 156 minutes after the earthquakes are observed. In the 1877 tsunami secondary effects were present mainly on the Peruvian coast. Finally, a new classification for near and far field tsunami is proposed.

  11. Homicide in Chile: Trends 2000-2012.

    PubMed

    Otzen, Tamara; Sanhueza, Antonio; Manterola, Carlos; Hetz, Monica; Melnik, Tamara

    2015-12-15

    Homicide, an external cause of morbidity and mortality, caused 473,000 deaths worldwide in 2012, a rate of 6.2 per 100,000 inhabitants. The aim of this study was to describe homicide mortality trends in Chile between 2000 and 2012 by year, gender, age group, geographic distribution (by zone and by region) and type of homicide. This was a population-based study. Data for homicide mortality in Chile between 2000 and 2012 were used and they were provided by the Chilean Ministry of Health's Department of Statistics and Health Information (DEIS) and PAHO/WHO. The homicide mortality rates were calculated per 100,000 inhabitants. The study variables were year, geographic distribution, gender, age group and type of homicide. The annual percentage change (APC) of the rates was analyzed, and a logarithm of the rates by year and region was fitted by applying linear regression models. In addition, relative risks (RR) were calculated. 95% confidence intervals were considered in all the analyses. The average yearly rate of homicide (HMR) in Chile (2000-2012) was 4.9. The rates were higher in men (8.7) than in women (1.1), with a RR of 8.2. The rates were higher in the country's central zone (5.0), increasing in recent years in the southern zone, with a significant positive APC of 1.1%. The Aisén Region had the highest rate (7.6), although Antofagasta was the region with the most significant APC (3.1%). The highest rate (9.2) was verified in the 25 to 39 age group. The highest rate (5.5) was recorded in 2005. The most frequent type of homicide was assault with an object (44.8%). Although the homicide rates are higher in the southern zone of the country, the northern zone is showing a tendency to increase, becoming an even more serious problem, which not only affects those directly involved, but society as a whole.

  12. Tsunami risk zoning in south-central Chile

    NASA Astrophysics Data System (ADS)

    Lagos, M.

    2010-12-01

    The recent 2010 Chilean tsunami revealed the need to optimize methodologies for assessing the risk of disaster. In this context, modern techniques and criteria for the evaluation of the tsunami phenomenon were applied in the coastal zone of south-central Chile as a specific methodology for the zoning of tsunami risk. This methodology allows the identification and validation of a scenario of tsunami hazard; the spatialization of factors that have an impact on the risk; and the zoning of the tsunami risk. For the hazard evaluation, different scenarios were modeled by means of numerical simulation techniques, selecting and validating the results that better fit with the observed tsunami data. Hydrodynamic parameters of the inundation as well as physical and socioeconomic vulnerability aspects were considered for the spatialization of the factors that affect the tsunami risk. The tsunami risk zoning was integrated into a Geographic Information System (GIS) by means of multicriteria evaluation (MCE). The results of the tsunami risk zoning show that the local characteristics and their location, together with the concentration of poverty levels, establish spatial differentiated risk levels. This information builds the basis for future applied studies in land use planning that tend to minimize the risk levels associated to the tsunami hazard. This research is supported by Fondecyt 11090210.

  13. The upper-mantle transition zone beneath the Chile-Argentina flat subduction zone

    NASA Astrophysics Data System (ADS)

    Bagdo, Paula; Bonatto, Luciana; Badi, Gabriela; Piromallo, Claudia

    2016-04-01

    The main objective of the present work is the study of the upper mantle structure of the western margin of South America (between 26°S and 36°S) within an area known as the Chile-Argentina flat subduction zone. For this purpose, we use teleseismic records from temporary broad band seismic stations that resulted from different seismic experiments carried out in South America. This area is characterized by on-going orogenic processes and complex subduction history that have profoundly affected the underlying mantle structure. The detection and characterization of the upper mantle seismic discontinuities are useful to understand subduction processes and the dynamics of mantle convection; this is due to the fact that they mark changes in mantle composition or phase changes in mantle minerals that respond differently to the disturbances caused by mantle convection. The discontinuities at a depth of 410 km and 660 km, generally associated to phase changes in olivine, vary in width and depth as a result of compositional and temperature anomalies. As a consequence, these discontinuities are an essential tool to study the thermal and compositional structure of the mantle. Here, we analyze the upper-mantle transition zone discontinuities at a depth of 410 km and 660 km as seen from Pds seismic phases beneath the Argentina-Chile flat subduction.

  14. Calbuco Volcano Erupts in Southern Chile

    NASA Image and Video Library

    2015-04-24

    Calbuco Volcano in southern Chile has erupted for the first time since 1972, with the last major eruption occurring in 1961 that sent ash columns 12-15 kilometers high. This image was taken by the Suomi NPP satellite's VIIRS instrument in a high resolution infrared channel around 0515Z on April 23, 2015. Credit: NOAA/NASA/NPP/VIIRS Credit: NOAA/NASA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  15. Structure and Neotectonics of the Southern Chile Forearc 35°S - 40°S

    NASA Astrophysics Data System (ADS)

    Geersen, Jacob; Völker, David; Weinrebe, Wilhelm; Krastel-Gudegast, Sebastian; Behrmann, Jan H.

    2010-05-01

    The Southern Chile Forearc exhibits an extreme level of neotectonic deformation. On-land studies have documented a pronounced segmentation in the region 36°S - 41°S. However, information on the seaward continuation of the individual segments towards the Chile Trench is rare, as direct observations end at the coastline and are replaced by a less dense set of marine geophysical data. In this study we use swath bathymetric data combined with high and low-frequency reflection seismic data as well as results from heat-flow measurements to: (A) map and identify active deformation structures and investigate their spatial distribution, and (B) analyse the factors controlling segmentation along the Southern Chile Forearc. Considering the region 35°S to 40°S we found evidence for a division into four major segments; Concepcion North, Concepcion South, Nahuelbuta, and Tolten (from North to South). Within all four segments, the lower continental slope is dissected by distinct margin-parallel thrust ridges overlying active landward-dipping thrust faults, indicating the presence of an active accretionary prism. The middle and upper slope, however, shows major differences between the four segments. The Concepcion North Segment is dominated by a large margin-parallel thrust ridge. The Concepcion South Segment shows large up to 600 m high north-south aligned normal fault scarps highlighting east-west extension. The change from thrust to normal faulting domains is accompanied by a drastic decrease in surface heat-flow by a factor of up to four. Further south in the Nahuelbuta Segment, east-west trending active thrust ridges indicate north-south compression of this part of the forearc. Shortening in this segment is not only limited to the middle and upper slope, but includes the entire marine forearc and occurs perpendicular to the direction of plate convergence. In the southernmost Tolten Segment the middle and upper continental slope shows no signs of compressive or extensional

  16. 46 CFR 42.30-10 - Southern Winter Seasonal Zone.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Island; thence the rhumb line to Black Rock Point on Stewart Island; thence the rhumb line to the point... BY SEA Zones, Areas, and Seasonal Periods § 42.30-10 Southern Winter Seasonal Zone. (a) The northern boundary of the Southern Winter Seasonal Zone is the rhumb line from the east coast of the American...

  17. Diet, dietary selectivity and density of South American grey fox, Lycalopex griseus, in Central Chile.

    PubMed

    Muñoz-Pedreros, Andrés; Yáñez, José; Norambuena, Heraldo V; Zúñiga, Alfredo

    2018-01-01

    The South American grey fox Lycalopex griseus is a canid widely distributed in southern South America; however, some aspects of its biology are still poorly known. We studied the diet and density of L. griseus in the Lago Peñuelas Biosphere Reserve, in Central Chile. The trophic niche breadth was B = 6.16 (B sta = 0.47) and prey diversity was H' = 2.46 (H max ' = 3.17, J' = 0.78). The highest proportions of prey consumed in the diet were Oryctolagus cuniculus (52.21%) and other mammals (32.78%). We compared these results with a latitudinal gradient of diet results for this species in Chile. L. griseus eats mostly mammals (>90% of total prey), consuming the rodent Phyllotis darwini and reptiles in the northern zone; Oryctolagus cuniculus, Octodon degus and Abrocoma bennetti in the central zone; Abrothrix spp. and lagomorphs in the southern zone; and Lepus capensis and Ovis aries in the austral zone. The estimated density of L. griseus in Lago Peñuelas NR was 1.3 foxes/km 2 . © 2017 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  18. Remarkably Consistent Thermal State of the south Central Chile Subduction Zone from 36°S to 45°S

    NASA Astrophysics Data System (ADS)

    Rotman, H.; Spinelli, G. A.

    2013-12-01

    Delineating the rupture areas of large subduction zone earthquakes is necessary for understanding the controls on seismic and aseismic slip on faults. For the largest recorded earthquake, an event in south central Chile in 1960 with moment magnitude 9.5, the rupture area is only loosely defined due to limitations in the global seismic network at the time. The rupture extends ~900 km along strike on the margin. Coastal deformation is consistent with either a constant rupture width of ~200 km along the entire length, or a much narrower width (~115 km) for the southern half of the rupture. A southward narrowing of the seismogenic zone has been hypothesized to result from warming of the subduction zone to the south, where the subducting plate is younger. Here, we present results of thermal models at 36°S, 38°S, 43°S, and 45°S to examine potential along-strike changes the thermal state of the margin. We find that temperatures in the subduction zone are strongly affected by both fluid circulation in the high permeability upper oceanic crust and frictional heating on the plate boundary fault. Hydrothermal circulation preferentially cools transects with young subducting lithosphere; frictional heating preferentially warms transects with older subducting lithosphere. The combined effects of frictional heating and hydrothermal circulation increase decollement temperatures in the 36°S and 38°S transects by up to ~155°C, and decrease temperatures in the 45°S transect by up to ~150°C. In our preferred models, decollement temperatures 200 km landward of the trench in all four transects are ~350-400°C. This is consistent with a constant ~200 km wide seismogenic zone for the 1960 Mw 9.5 rupture, with decreasing slip magnitude in the southern half of the rupture.

  19. Size variation of Acacia caven (leguminosae) pods along a climatic gradient in Chile

    NASA Astrophysics Data System (ADS)

    Gutiérrez, J. R.; Armesto, J. J.

    1981-06-01

    A southward tendency of increment in pod-length is shown for 11 populations of Acacia caven (Mol.) Hook et Arn. localized along a climatic gradient of increasing annual rainfall in Chile. This fact would suggest that A. caven populations occurring in the south are in better conditions for reproduction than northern populations, since pod-length is related to the amount of seeds inside the pods. The possible bearing of this southward tendency of increasing seed production upon the expansion of A. caven toward the more humid zones in southern Chile is discussed.

  20. Hantavirus pulmonary syndrome, Southern Chile, 1995-2012.

    PubMed

    Riquelme, Raúl; Rioseco, María Luisa; Bastidas, Lorena; Trincado, Daniela; Riquelme, Mauricio; Loyola, Hugo; Valdivieso, Francisca

    2015-04-01

    Hantavirus is endemic to the Region de Los Lagos in southern Chile; its incidence is 8.5 times higher in the communes of the Andean area than in the rest of the region. We analyzed the epidemiologic aspects of the 103 cases diagnosed by serology and the clinical aspects of 80 hospitalized patients during 1995-2012. Cases in this region clearly predominated during winter, whereas in the rest of the country, they occur mostly during summer. Mild, moderate, and severe disease was observed, and the case-fatality rate was 32%. Shock caused death in 75% of those cases; high respiratory frequency and elevated creatinine plasma level were independent factors associated with death. Early clinical suspicion, especially in rural areas, should prompt urgent transfer to a hospital with an intensive care unit and might help decrease the high case-fatality rate.

  1. Discovery of a blue whale feeding and nursing ground in southern Chile.

    PubMed Central

    Hucke-Gaete, Rodrigo; Osman, Layla P; Moreno, Carlos A; Findlay, Ken P; Ljungblad, Don K

    2004-01-01

    After the extensive exploitation that reduced the Southern Hemisphere blue whale (Balaenoptera musculus) populations to less than 3% of its original numbers, studies on its recovery have been compounded by the inaccessibility of most populations and the extensive migrations between low and high latitudes, thus ensuring that knowledge about blue whale ecology and status remains limited. We report the recent discovery of, arguably, the most important blue whale feeding and nursing ground known to date in the Southern Hemisphere, which is located near the fjords off southern Chile. Through aerial and marine surveys (n = 7) 47 groups, comprising 153 blue whales including at least 11 mother-calf pairs, were sighted during the austral summer and early autumn of 2003. The implications of this discovery on the biological understanding and conservation of this endangered species are discussed. PMID:15252974

  2. Discovery of a blue whale feeding and nursing ground in southern Chile.

    PubMed

    Hucke-Gaete, Rodrigo; Osman, Layla P; Moreno, Carlos A; Findlay, Ken P; Ljungblad, Don K

    2004-05-07

    After the extensive exploitation that reduced the Southern Hemisphere blue whale (Balaenoptera musculus) populations to less than 3% of its original numbers, studies on its recovery have been compounded by the inaccessibility of most populations and the extensive migrations between low and high latitudes, thus ensuring that knowledge about blue whale ecology and status remains limited. We report the recent discovery of, arguably, the most important blue whale feeding and nursing ground known to date in the Southern Hemisphere, which is located near the fjords off southern Chile. Through aerial and marine surveys (n = 7) 47 groups, comprising 153 blue whales including at least 11 mother-calf pairs, were sighted during the austral summer and early autumn of 2003. The implications of this discovery on the biological understanding and conservation of this endangered species are discussed.

  3. The Evolution of Seabirds in the Humboldt Current: New Clues from the Pliocene of Central Chile

    PubMed Central

    Chávez Hoffmeister, Martín; Carrillo Briceño, Jorge D.; Nielsen, Sven N.

    2014-01-01

    Background During the last decade, new Neogene fossil assemblages from South America have revealed important clues about the evolution of seabird faunas in one of the major upwelling systems of the world: the Humboldt Current. However, most of this record comes from arid Northern Chile and Southern Peru and, in consequence, our knowledge of the evolutionary history of seabirds in the temperate transitional zone is negligible. A new Late Pliocene assemblage of fossil birds from the coastal locality of Horcon in Central Chile offers a unique opportunity to fill this gap. Principal Findings Isolated bones of a medium-sized penguin are the most abundant bird remains. Morphological and cladistic analyses reveal that these specimens represent a new species of crested penguin, Eudyptes calauina sp. nov. Eudyptes is a penguin genus that inhabit temperate and subantarctic regions and currently absent in central Chile. Additionally, a partial skeleton of a small species of cormorant and a partial tarsometatarsus of a sooty shearwater have been identified. Conclusion/Significance The Horcon fossils suggest the existence of a mixed avifauna in central Chile during the Pliocene in concordance with the latitudinal thermal gradient. This resembles the current assemblages from the transitional zone, with the presence of species shared with Northern Chile and Southern Peru and a previously unrecorded penguin currently absent from the Humboldt System but present in the Magellanic region. Comparison of Pliocene seabird diversity across the Pacific coast of South America shows that the Horcon avifauna represents a distinctive assemblage linking the living faunas with the Late Miocene ones. A comparison with the fossil record near the Benguela Current (west coast of southern Africa) suggests that the thermic gradient could play an important role in the preservation of a higher diversity of cold/temperate seabirds in the Humboldt Current. PMID:24621560

  4. Nitrogen excretion by copepods and its contribution to the ammonium oxidizing activity in the upwelling zone off central-southern Chile (36°S)

    NASA Astrophysics Data System (ADS)

    Valdes, V.; Escribano, R.; Fernandez, C.; Molina, V.

    2016-02-01

    Zooplankton play a pivotal role in the nitrogen cycle by sustaining phytoplankton and heterotrophic bacterial growth through N excretion. This biogeochemical interaction between microbial community and zooplankton has been poorly studied in the ocean. In this work we explored the interaction between the nitrogen compounds excreted by dominant copepods in the upwelling zone off central Chile and the activity of ammonium oxidizing microbial community. For doing so, two experiments were conducted in May and early September 2010 off Concepción (36°S) in central-southern Chile upon non-upwelling condition. Among organic and inorganic nitrogen compounds excreted by copepods (NH4+, DON, NO3- and NO2-), DON was the most abundant. In the first experiment, DON excretion rate was <0.6 μmol L-1 h-1 in the first hours of incubation, while in the second experiment we found values of 0.9 μmol L-1 h-1 in the last hour of incubation. NH4+ excretion rates were lower than those of DON, with values ca. 0.02 and < 0.4 μmol L-1 h-1 in autumn and winter, respectively. When assessing the response of microbial ammonium oxidizing groups to the input of these excreted products, it was found that NH4+ was significantly consumed in the first four hours of incubation in the autumn experiment, while bacterioplankton abundance incremented to 8 x105 to 1.2 x106 cells mL-1 after 6 hours. The activity of AOB and AOA amoA transcript copies increased from 1,539 to 5,669 copies mL-1 and 1,510 a 3,763 copies mL-1, respectively. In the second experiment, NH4+ showed complete consumption in the first two hours of incubation and specific groups of AOA and AOB transcript were below <10,000 copies mL-1. Our findings confirm, that NH4+ is not the main compound excreted by copepods, and this can be directly used by bacterioplankton and AOB followed by AOA response to available NH4+. Both are able to utilize a large proportion of ammonium excreted by the copepods during austral autumn and winter.

  5. Risk factor analysis for sea lice, Caligus rogercresseyi, levels in farmed salmonids in southern Chile.

    PubMed

    Yatabe, T; Arriagada, G; Hamilton-West, C; Urcelay, S

    2011-05-01

    Sea lice, Caligus rogercresseyi, are ectoparasitic copepods, which severely affect the salmon farming industry in southern Chile, reducing the health status of fish and producing both direct and indirect economic losses. Local farmers have reported increasing infestation levels since 2004, reaching a peak in 2007. In response to this situation, the Chilean Fisheries Service (Sernapesca) developed a surveillance programme; the first step of which consisted of a general survey of salmon farms. This survey included documenting counts of parasite burdens on fish and measurements of several husbandry and environmental factors providing an evaluation of risk factors for the observed infestation levels. The information collected was analysed using a linear mixed model technique, which takes into account the clustered structure of data, decomposing the unexplained variation and assigning it to different aggregation levels of the productive system. Geographical zones, fish species, treatment against sea lice performed 1 month before sampling, stocking density, fish weight and water salinity were the variables significantly associated with sea lice burdens. In contrast, treatments performed 2-3 months before sampling, use of photoperiod in sea cages and water temperature, were not significant. There was significant unexplained variation at all aggregation levels, i.e. sub-zone, fish farm and cage level, with the fish farm level showing the greatest variation. © 2011 Blackwell Publishing Ltd.

  6. Chile's seismogenic coupling zones - geophysical and neotectonic observations from the South American subduction zone prior to the Maule 2010 earthquake

    NASA Astrophysics Data System (ADS)

    Oncken With Tipteq, Onno; Ipoc Research Groups

    2010-05-01

    Accumulation of deformation at convergent plate margins is recently identified to be highly discontinuous and transient in nature: silent slip events, non-volcanic tremors, afterslip, fault coupling and complex response patterns of the upper plate during a single event as well as across several seismic cycles have all been observed in various settings and combinations. Segments of convergent plate margins with high recurrence rates and at different stages of the rupture cycle like the Chilean margin offer an exceptional opportunity to study these features and their interaction resolving behaviour during the seismic cycle and over repeated cycles. A past (TIPTEQ) and an active international initiative (IPOC; Integrated Plate Boundary Observatory Chile) address these goals with research groups from IPG Paris, Seismological Survey of Chile, Free University Berlin, Potsdam University, Hamburg University, IFM-GEOMAR Kiel, and GFZ Potsdam employing an integrated plate boundary observatory and associated projects. We focus on the south Central Chilean convergent margin and the North Chilean margin as natural laboratories embracing the recent Maule 2010 megathrust event. Here, major recent seismic events have occurred (south Central Chile: 1960, Mw = 9.5; 2010, Mw = 8.8; North Chile: 1995, Mw = 8; 2001, Mw = 8.7; 2007, Mw: 7.8) or are expected in the very near future (Iquique, last ruptured 1877, Mw = 8.8) allowing observation at critical time windows of the seismic cycle. Seismic imaging and seismological data have allowed us to relocate major rupture hypocentres and to locate the geometry of the locked zone and the degree of locking in both areas. The reflection seismic data exhibit well defined changes of reflectivity and Vp/Vs ratio along the plate interface that can be correlated with different parts of the coupling zone as well as with changes during the seismic cycle. Observations suggest an important role of the hydraulic system, an inference that is strongly

  7. The effect of offset on fracture permeability of rocks from the Southern Andes Volcanic Zone, Chile

    NASA Astrophysics Data System (ADS)

    Pérez-Flores, P.; Wang, G.; Mitchell, T. M.; Meredith, P. G.; Nara, Y.; Sarkar, V.; Cembrano, J.

    2017-11-01

    The Southern Andes Volcanic Zone (SVZ) represents one of the largest undeveloped geothermal provinces in the world. Development of the geothermal potential requires a detailed understanding of fluid transport properties of its main lithologies. The permeability of SVZ rocks is altered by the presence of fracture damage zones produced by the Liquiñe-Ofqui Fault System (LOFS) and the Andean Transverse Faults (ATF). We have therefore measured the permeability of four representative lithologies from the volcanic basement in this area: crystalline tuff, andesitic dike, altered andesite and granodiorite. For comparative purposes, we have also measured the permeability of samples of Seljadalur basalt, an Icelandic rock with widely studied and reported hydraulic properties. Specifically, we present the results of a systematic study of the effect of fractures and fracture offsets on permeability as a function of increasing effective pressure. Baseline measurements on intact samples of SVZ rocks show that the granodiorite has a permeability (10-18 m2), two orders of magnitude higher than that of the volcanic rocks (10-20 m2). The presence of throughgoing mated macro-fractures increases permeability by between four and six orders of magnitude, with the highest permeability recorded for the crystalline tuff. Increasing fracture offset to produce unmated fractures results in large increases in permeability up to some characteristic value of offset, beyond which permeability changes only marginally. The increase in permeability with offset appears to depend on fracture roughness and aperture, and these are different for each lithology. Overall, fractured SVZ rocks with finite offsets record permeability values consistent with those commonly found in geothermal reservoirs (>10-16 m2), which potentially allow convective/advective flow to develop. Hence, our results demonstrate that the fracture damage zones developed within the SVZ produce permeable regions, especially within the

  8. Tsunamigenic scenarios for southern Peru and northern Chile seismic gap: Deterministic and probabilistic hybrid approach for hazard assessment

    NASA Astrophysics Data System (ADS)

    González-Carrasco, J. F.; Gonzalez, G.; Aránguiz, R.; Yanez, G. A.; Melgar, D.; Salazar, P.; Shrivastava, M. N.; Das, R.; Catalan, P. A.; Cienfuegos, R.

    2017-12-01

    Plausible worst-case tsunamigenic scenarios definition plays a relevant role in tsunami hazard assessment focused in emergency preparedness and evacuation planning for coastal communities. During the last decade, the occurrence of major and moderate tsunamigenic earthquakes along worldwide subduction zones has given clues about critical parameters involved in near-field tsunami inundation processes, i.e. slip spatial distribution, shelf resonance of edge waves and local geomorphology effects. To analyze the effects of these seismic and hydrodynamic variables over the epistemic uncertainty of coastal inundation, we implement a combined methodology using deterministic and probabilistic approaches to construct 420 tsunamigenic scenarios in a mature seismic gap of southern Peru and northern Chile, extended from 17ºS to 24ºS. The deterministic scenarios are calculated using a regional distribution of trench-parallel gravity anomaly (TPGA) and trench-parallel topography anomaly (TPTA), three-dimensional Slab 1.0 worldwide subduction zones geometry model and published interseismic coupling (ISC) distributions. As result, we find four higher slip deficit zones interpreted as major seismic asperities of the gap, used in a hierarchical tree scheme to generate ten tsunamigenic scenarios with seismic magnitudes fluctuates between Mw 8.4 to Mw 8.9. Additionally, we construct ten homogeneous slip scenarios as inundation baseline. For the probabilistic approach, we implement a Karhunen - Loève expansion to generate 400 stochastic tsunamigenic scenarios over the maximum extension of the gap, with the same magnitude range of the deterministic sources. All the scenarios are simulated through a non-hydrostatic tsunami model Neowave 2D, using a classical nesting scheme, for five coastal major cities in northern Chile (Arica, Iquique, Tocopilla, Mejillones and Antofagasta) obtaining high resolution data of inundation depth, runup, coastal currents and sea level elevation. The

  9. The Unexpected Awakening of Chaitén Volcano, Chile

    NASA Astrophysics Data System (ADS)

    Carn, Simon A.; Pallister, John S.; Lara, Luis; Ewert, John W.; Watt, Sebastian; Prata, Alfred J.; Thomas, Ronald J.; Villarosa, Gustavo

    2009-06-01

    On 2 May 2008, a large eruption began unexpectedly at the inconspicuous Chaitén volcano in Chile's southern volcanic zone. Ash columns abruptly jetted from the volcano into the stratosphere, followed by lava dome effusion and continuous low-altitude ash plumes [Lara, 2009]. Apocalyptic photographs of eruption plumes suffused with lightning were circulated globally. Effects of the eruption were extensive. Floods and lahars inundated the town of Chaitén, and its 4625 residents were evacuated. Widespread ashfall and drifting ash clouds closed regional airports and cancelled hundreds of domestic flights in Argentina and Chile and numerous international flights [Guffanti et al., 2008]. Ash heavily affected the aquaculture industry in the nearby Gulf of Corcovado, curtailed ecotourism, and closed regional nature preserves. To better prepare for future eruptions, the Chilean government has boosted support for monitoring and hazard mitigation at Chaitén and at 42 other highly hazardous, active volcanoes in Chile.

  10. The Unexpected Awakening of Chaitén Volcano, Chile

    USGS Publications Warehouse

    Carn, Simon A.; Zogorski, John S.; Lara, Luis; Ewert, John W.; Watt, Sebastian; Prata, Alfred J.; Thomas, Ronald J.; Villarosa, Gustavo

    2009-01-01

    On 2 May 2008, a large eruption began unexpectedly at the inconspicuous Chaitén volcano in Chile's southern volcanic zone. Ash columns abruptly jetted from the volcano into the stratosphere, followed by lava dome effusion and continuous low-altitude ash plumes [Lara, 2009]. Apocalyptic photographs of eruption plumes suffused with lightning were circulated globally. Effects of the eruption were extensive. Floods and lahars inundated the town of Chaitén, and its 4625 residents were evacuated. Widespread ashfall and drifting ash clouds closed regional airports and cancelled hundreds of domestic flights in Argentina and Chile and numerous international flights [Guffanti et al., 2008]. Ash heavily affected the aquaculture industry in the nearby Gulf of Corcovado, curtailed ecotourism, and closed regional nature preserves. To better prepare for future eruptions, the Chilean government has boosted support for monitoring and hazard mitigation at Chaitén and at 42 other highly hazardous, active volcanoes in Chile.

  11. Protection of Existing and Potential Astronomical Sites in Chile - an Update.

    NASA Astrophysics Data System (ADS)

    Smith, M. G.; Sanhueza, P.; Norman, D.; Schwarz, H.; Orellana, D.

    2002-12-01

    The IAU's Working Group on Controlling Light Pollution (iauwg) has declared Mauna Kea and a wide strip of Northern Chile between Antofagasta and Chajnanator as top priorities for its efforts to protect existing and potential sites in the Northern and Southern hemispheres respectively. This report provides an update on the iauwg's co-ordinated efforts to protect areas around the major international optical observatories in Chile, as well as the "Chilean Special Zone" (CSZ) mentioned above. This zone is of current and potential interest for the installation of extremely large optical telescopes and includes the ALMA radio-astronomy site. The CSZ is potentially vulnerable to adverse effects of mining in the region. Progess has been made in demonstrating to local mining interests within the CSZ the economic advantages of quality lighting. Educational and outreach activities to a variety of target audiences are building on legislation covering dark skies - itself part of work by the Chilean government to protect the natural heritage of Chile. Substantial good will was generated by an international, bilingual conference held last March in Chile. Just in the region around AURA's Observatory in Chile (Gemini South, CTIO and SOAR), a portable planetarium has been used to reach out to over 600 teachers and 65,000 pupils in the RedLaSer schools network within the last three years. This has attracted the direct interest of Chile's Ministry of Education. Videoconferencing over Internet2 is being used for educational purposes between Chile and various sites in the US. The NSF- initiated Mamalluca municipal observatory now receives more visitors than all the international observatories in Chile combined and is the focus of an expanding local industry of astronomical eco-tourism. Most of this work was supported by funding from, or via, the US NSF through CTIO and Gemini, and from ESO, OCIW, CONAMA and the IDA.

  12. Hantavirus Pulmonary Syndrome , Southern Chile, 1995–2012

    PubMed Central

    Riquelme, Raúl; Rioseco, María Luisa; Bastidas, Lorena; Trincado, Daniela; Riquelme, Mauricio; Loyola, Hugo; Valdivieso, Francisca

    2015-01-01

    Hantavirus is endemic to the Region de Los Lagos in southern Chile; its incidence is 8.5 times higher in the communes of the Andean area than in the rest of the region. We analyzed the epidemiologic aspects of the 103 cases diagnosed by serology and the clinical aspects of 80 hospitalized patients during 1995–2012. Cases in this region clearly predominated during winter, whereas in the rest of the country, they occur mostly during summer. Mild, moderate, and severe disease was observed, and the case-fatality rate was 32%. Shock caused death in 75% of those cases; high respiratory frequency and elevated creatinine plasma level were independent factors associated with death. Early clinical suspicion, especially in rural areas, should prompt urgent transfer to a hospital with an intensive care unit and might help decrease the high case-fatality rate. PMID:25816116

  13. Ridge-trench collision in Archean and Post-Archean crustal growth: Evidence from southern Chile

    NASA Technical Reports Server (NTRS)

    Nelson, E. P.; Forsythe, R. D.

    1988-01-01

    The growth of continental crust at convergent plate margins involves both continuous and episodic processes. Ridge-trench collision is one episodic process that can cause significant magmatic and tectonic effects on convergent plate margins. Because the sites of ridge collision (ridge-trench triple junctions) generally migrate along convergent plate boundaries, the effects of ridge collision will be highly diachronous in Andean-type orogenic belts and may not be adequately recognized in the geologic record. The Chile margin triple junction (CMTJ, 46 deg S), where the actively spreading Chile rise is colliding with the sediment-filled Peru-Chile trench, is geometrically and kinematically the simplest modern example of ridge collision. The south Chile margin illustrates the importance of the ridge-collision tectonic setting in crustal evolution at convergent margins. Similarities between ridge-collision features in southern Chile and features of Archean greenstone belts raise the question of the importance of ridge collision in Archean crustal growth. Archean plate tectonic processes were probably different than today; these differences may have affected the nature and importance of ridge collision during Archean crustal growth. In conclusion, it is suggested that smaller plates, greater ridge length, and/or faster spreading all point to the likelihood that ridge collision played a greater role in crustal growth and development of the greenstone-granite terranes during the Archean. However, the effects of modern ridge collision, and the processes involved, are not well enough known to develop specific models for the Archean ridge collison.

  14. Counternarcotic Efforts in the Southern Cone: Chile

    DTIC Science & Technology

    1990-06-30

    deportation is simply not practical . Statistics of cocaine coming into Chile by "ant smuggling" do not exist. Carabineros mentions that according to...existing evidence is contradictory. A recent report ordered by the Ministry of Foreign 10 Affairs does not support the allegation that Chile is being used...Gugliotta and Jeff Leen, Kings of Cocaine (New York: Harper and Row, 1989) p.23. 11 industry based in Chile and controlled by a few refiners who bought

  15. Crustal Thickness and Structure in Southern Chile: Patagonia plate assembly structures and continental arc modifications

    NASA Astrophysics Data System (ADS)

    Rodriguez, E. E.; Russo, R. M.

    2016-12-01

    Crustal structure is the product of the processes that operated during a region's tectonic history. For Patagonia, these tectonic processes include its early Paleozoic assembly and accretion to the South America portion of Gondwana, Triassic rifting of Gondwana, and a long history as the upper plate during oceanic subduction since the Mesozoic. To assess the crustal structure and glean insight into how these tectonic processes affected the region, we combined data from two seismic networks, the Chile Ridge Subduction Project and Seismic Experiment of Aisen Chile - yielding a total of 77 broadband seismic stations - deployed from 2004 to 2007. The stations were concentrated 300 km inboard of the Chile trench, above structures unlikely to have been affected by ongoing Chile Ridge subduction. Events suitable for receiver function (RF) analyses (M > 5.9, of various backazimuths, epicentral distances of 30 - 90°) yielded 995 radial RFs, constructed using iterative time deconvolution (Ligorria and Ammon, 1999). We estimated crustal thicknesses and compressional to shear wave velocity ratios (Vp/Vs) using the H-k grid search method (Zhu and Kanamori, 2000); common conversion point (CCP) stacking (Zhu, et al., 2006) allowed imaging of crustal structure. Results limit crustal thicknesses to between 30 and 45 km. The crust varies smoothly from 30 km at the N margin of our study area ( 43°S) to a max depth of 45 km at 44.75°S, shallowing to 30 km at 49°S. On E-W CCP sections north of 46°S, the Moho dips westward, from a depth of 35 at 71°W to 45 km at its deepest near 72.75°W. Beneath the active Southern Volcanic Zone, which is bounded to the west by the Liquiñe-Ofqui fault, the Moho is ambiguous, producing unclear Ps phases possibly reflecting a lack of sharp impedance contrast or poor conversion efficiency at the base of the crust, perhaps due to deep-seated volcanic arc processes. The proximity of the Liquiñe-Ofqui strike-slip fault may also complicate the

  16. Transboundary protected area proposals along the Southern Andes of Chile and Argentina: Status of current efforts

    Treesearch

    Peter Keller

    2007-01-01

    An evolving network of protected areas along the southern Andes of Chile and Argentina-the heart of Patagonia-are in various stages of evaluation and potential Transboundary Protected Area designations. This paper examines three such efforts. The first proposal is the North Andean-Patagonia Regional Eco-Corridor, which was the subject of a recent bilateral meeting...

  17. Inbreeding and immigration in urban and rural zones of Chile, with an endogamy index.

    PubMed

    Lazo, B; Campusano, C; Figueroa, H; Pinto-Cisternas, J; Zambra, E

    1978-01-01

    In order to establish relationships among immigration, inbreeding, and age at marriage in urban and rural zones in Chile, and to formulate an endogamy index, ecclesiastical and civil data on consanguinity from 1865-1914 were analyzed, and a random mating deviation index was developed, with resulting values indicating deviation toward endogamy in both zones. Data grouped by zones and decades include means of population and density, nuptiality, consanguineous marriages (number, types, frequencies, and inbreeding coefficients), and frequencies of immigrants among consanguineous and nonconsanguineous couples. All of these values differ markedly between zones, with values in the rural zone double those in the urban zone. In the 2 zones, there are no clear differences in age at marriage between consanguineous and nonconsanguineous couples, and this is an important finding. From the point of view of fertility, one can expect a similar length period of fertility for both groups of couples. In this case, lower fertility might be expected in consanguineous marriages, only because of a higher probability of homozygosis of deleterious genes.

  18. Two new Liolaemus lizards from the Andean highlands of Southern Chile (Squamata, Iguania, Liolaemidae)

    PubMed Central

    Troncoso-Palacios, Jaime; Diaz, Hugo A.; Puas, German I.; Riveros-Riffo, Edvin; Elorza, Alvaro A.

    2016-01-01

    Abstract Liolaemus is a diverse genus of lizards, subdivided into two subgenera: Liolaemus (sensu stricto) and Eulaemus, distributed mainly in Chile and Argentina. The Liolaemus elongatus-kriegi complex is the most diverse group within Liolaemus (sensu stricto), especially the species closely related to Liolaemus elongatus, which form a clade currently comprising nine species. Several Chilean species of this group have been recently described, mainly from volcanoes and poorly explored mountains. Here molecular and morphological evidence are provided for a new species of the Liolaemus elongatus clade, which is characterized by its small size and lack of dorsal pattern, unusual features for the species of this group of lizards. Additionally, the lack of precloacal pores in males of Liolaemus (sensu stricto) is a trait found in few species, which do not constitute a monophyletic group. A second new southern Chilean species is also described, without precloacal pores and supported by molecular phylogenetics to be related to Liolaemus villaricensis. Both new species were found in the same locality, near a lake located in a pre-Andean zone with Araucaria and Nothofagus forest. The two species are dedicated to prominent Lonkos (tribal chiefs) of the Mapuche and Pehuenche people: Janequeo and Leftraru. Additionally, the phylogenetic results suggest that Liolaemus lonquimayensis is a synonym of Liolaemus elongatus. PMID:27920609

  19. Rapid uplift in Laguna del Maule volcanic field of the Andean Southern Volcanic zone (Chile) 2007-2012

    NASA Astrophysics Data System (ADS)

    Feigl, Kurt L.; Le Mével, Hélène; Tabrez Ali, S.; Córdova, Loreto; Andersen, Nathan L.; DeMets, Charles; Singer, Bradley S.

    2014-02-01

    The Laguna del Maule (LdM) volcanic field in Chile is an exceptional example of postglacial rhyolitic volcanism in the Southern Volcanic Zone of the Andes. By interferometric analysis of synthetic aperture radar (SAR) images acquired between 2007 and 2012, we measure exceptionally rapid deformation. The maximum vertical velocity exceeds 280 mm yr-1. Although the rate of deformation was negligible from 2003 January to 2004 February, it accelerated some time before 2007 January. Statistical testing rejects, with 95 per cent confidence, four hypotheses of artefacts caused by tropospheric gradients, ionospheric effects, orbital errors or topographic relief, respectively. The high rate of deformation is confirmed by daily estimates of position during several months in 2012, as measured by analysis of signals transmitted by the Global Positioning System (GPS) and received on the ground at three stations around the reservoir forming the LdM. The fastest-moving GPS station (MAU2) has a velocity vector of [-180 ± 4, 46 ± 2, 280 ± 4] mm yr-1 for the northward, eastward and upward components, respectively, with respect to the stable interior of the South America Plate. The observed deformation cannot be explained by changes in the gravitational load caused by variations in the water level in the reservoir. For the most recent observation time interval, spanning 44 d in early 2012, the model that best fits the InSAR observations involves an inflating sill at a depth of 5.2 ± 0.3 km, with length 9.0 ± 0.3 km, width 5.3 ± 0.4 km, dip 20 ± 3° from horizontal and strike 14 ± 5° clockwise from north, assuming a rectangular dislocation in a half-space with uniform elastic properties. During this time interval, the estimated rate of tensile opening is 1.1 ± 0.04 m yr-1, such that the rate of volume increase in the modelled sill is 51 ± 5 million m3 yr-1 or 1.6 ± 0.2 m3 s-1. From 2004 January to 2012 April the total increase in volume was at least 0.15 km3 over the 5.2-yr

  20. Coupled geohazards at Southern Andes (Copahue-Lanín volcanoes): Chile's GEO supersite proposal

    NASA Astrophysics Data System (ADS)

    Lara, Luis E.; Cordova, Loreto

    2017-04-01

    volcanism (the so-called Red Nacional de Vigilancia Volcánica at Sernageomin) and tectonics (Centro Sismólogico Nacional at Universidad de Chile) allow a good complement with space-borne data (e.g., we observed deformation by GPS and InSAR at Villarrica volcano related to the March 3, 2015 eruption) in order to promote basic and applied research for a successful national strategy of disaster risk reduction. In addition, at least 3 active national research grants focus in this area and a number of young scientists are working there. Thus, we propose the Copahue-Lanín (37.5-39.5°S) segment of the Southern Volcanic Zone as a Geohazards Supersite and look forward for an enhanced engagement of the scientific community in this area.

  1. Strength of plate coupling in the southern Ryukyu subduction zone

    NASA Astrophysics Data System (ADS)

    Doo, Wen-Bin; Lo, Chung-Liang; Wu, Wen-Nan; Lin, Jing-Yi; Hsu, Shu-Kun; Huang, Yin-Sheng; Wang, Hsueh-Fen

    2018-01-01

    Understanding the strength of a plate coupling is critical for assessing potential seismic and tsunamic hazards in subduction zones. The interaction between an overriding plate and the associated subducting plate can be used to evaluate the strength of plate coupling by examining the mantle lithospheric buoyancy. Here, we calculate the mantle lithosphere buoyancy across the northern portion of the southern Ryukyu subduction zone based on gravity modeling with the constraints from a newly derived P-wave seismic velocity model. The result indicates that the strength of the plate coupling in the study area is relatively strong, which is consistent with previous observations in the southernmost Ryukyu subduction zone. Because few large earthquakes (Mw > 7) have occurred in the southern Ryukyu subduction zone, a large amount of energy is locked and accumulated by plate coupling, that could be released in the near future.

  2. Intrathermocline eddies in the coastal transition zone off central Chile (31-41°S)

    NASA Astrophysics Data System (ADS)

    Hormazabal, Samuel; Combes, Vincent; Morales, Carmen E.; Correa-Ramirez, Marco A.; Di Lorenzo, Emmanuel; Nuñez, Sergio

    2013-10-01

    The three-dimensional structure and the origin of mesoscale anticyclonic intrathermocline eddies (ITEs) in the coastal transition zone (CTZ) off central Chile (31-41°S) were analyzed through the combination of data from oceanographic cruises and satellite altimetry, and the application of an eddy-resolving primitive equation ocean model coupled with a numerical experiment using a passive tracer. In this region, ITEs are represented by subsurface lenses (˜100 km diameter; 500 m thickness or vertical extension) of nearly homogeneous salinity (>34.5) and oxygen-deficient (<1.0 mL L-1) waters, properties which are linked to the equatorial subsurface water mass (ESSW) transported poleward by the Peru-Chile undercurrent (PCUC) in the coastal band. At least five to seven ITEs were observed simultaneously in the area between 31° and 38°S during winter cruises in 1997 and 2009. Satellite data indicated that the ITEs identified from in situ data moved westward, each at a mean speed of ˜2 km d-1 and transported a total volume of ˜1 × 106 m3 s-1 (=1 Sv); the lifespan of each ITE ranged from a few months to 1 year. Model results indicate that ITEs become detached from the PCUC under summer upwelling conditions in the coastal zone.

  3. Effects of seasonal variability in across- and alongshore transport of anchoveta ( Engraulis ringens) larvae on model-based pre-recruitment indices off central Chile

    NASA Astrophysics Data System (ADS)

    Parada, Carolina; Colas, Francois; Soto-Mendoza, Samuel; Castro, Leonardo

    2012-01-01

    An individual-based model (IBM) of anchoveta ( Engraulis ringens) larvae was coupled to a climatological hydrodynamic (Regional Oceanic Modeling System, ROMS) model for central-southern Chile to answer the question as to whether or not across- and alongshore transport off central-southern Chile enhances retention in the spawning areas during the winter and summer reproductive periods, using model-based pre-recruitment indices (simulated transport success to nursery areas). The hydrodynamic model validation showed that ROMS captures the mean Seas Surface Temperature and Eddie Kinetic Energy observed in satellite-based data over the entire region. The IBM was used to simulate the transport of eggs and larvae from spawning zones in central Chile (Constitución, Dichato, Gulf of Arauco and Lebu-Corral) to historical nursery areas (HRZ, region between 35°S and 37°S). Model results corroborated HRZ as the most successful pre-recruitment zone (particles originated in the Dichato and Gulf of Arauco spawning areas), as well as identifying Lebu-Corral as a zone of high retention with a high associated pre-recruitment index (particles originated in the Lebu-Corral spawning zone). The highest pre-recruitment values were mainly found in winter. The Constitución and Dichato spawning zones displayed a typical summer upwelling velocity pattern, while the Gulf of Arauco in summertime showed strong offshore and alongshore velocity components. The Lebu-Corral region in winter presented important near-surface cross-shore transport towards the coast (associated with downwelling events), this might be one of the major mechanisms leading to high retention levels and a high pre-recruitment index for Lebu-Corral spawning zone. The limitations of the modeling approach are discussed and put into perspective for future work.

  4. Educating "Barbaros": Educational Policies on the Latin American Frontiers between Colonies and Independent Republics (Araucania, Southern Chile/Sonora, Mexico)

    ERIC Educational Resources Information Center

    Holck, Lasse; Saiz, Monika Contreras

    2010-01-01

    This article compares the methods and means employed by the state to enforce the education of (semi-)autonomous indigenous groups in southern Chile and northwestern Mexico (Sonora), border regions in the Latin American periphery, covering the transition from colonial times to the consolidation of independent republics until the middle of the…

  5. Chile.

    PubMed

    1988-09-01

    Chile is a long (2650 miles), narrow (250 miles at widest point) country sandwiched between the Andes mountains and the Pacific. The northern desert is rich in copper and nitrates; the temperate middle region is agricultural and supports the major cities, including Santiago, the capital, and the port of Valparaiso; and the southern region is a cold and damp area of forests, grasslands, lakes, and fjords. The country is divided into 12 administrative regions. Chile's population of 12.5 million are mainly of Spanish or Indian descent or mestizos. Literacy is 92.3%, and the national language is Spanish. Infant mortality is 18.1/1000, and life expectancy is 68.2 years. 82% of the people are urban, and most are Roman Catholics. Chile was settled by the Spanish in 1541 and attached to the Viceroyalty of Peru. Independence was won in 1818 under the leadership of Bernardo O'Higgins. In the 1880s Chile extended its sovereignty over the Strait of Magellan in the south and areas of southern Peru and Bolivia in the north. An officially parliamentary government, elected by universal suffrage, drifted into oligarchy and finally into a military dictatorship under Carlos Ibanez in 1924. Constitutional government was restored in 1932. The Christian Democratic government of Eduardo Frei (1964-70) inaugurated major reforms, including land redistribution, education, and far-reaching social and economic policies. A Marxist government under Salvador Allende lasted from 1970 to 1973 when the present military government of General Pinochet Ugarte took power, overthrew Allende, abolished the Congress, and banned political parties. It has moved the country in the direction of a free market economy but at the cost of systematic violations of human rights. A new constitution was promulgated in 1981, and congressional elections have been scheduled for October, 1989. A "National Accord for Transition to Full Democracy" was mediated by the Catholic Church in 1985. The social reforms of the

  6. Description of the Terrestrial Larva of Parosca latipalpis (Macquart) (Diptera: Tabanidae) from Southern Chile.

    PubMed

    González, C R; Llanos, L; Saldarriaga-Córdoba, M

    2016-10-01

    The terrestrial larva of the austral horsefly, Parosca latipalpis (Macquart), identified by molecular techniques, is described. The larva of P. latipalpis resembles Scaptia auriflua (Donovan), Copidapha vicina (Taylor), Myioscaptia muscula (English), and Osca lata (Guérin-Meneville) in many morphological characters, as well as in their terrestrial habitats. Some characters that are shared between these species are unique among Tabanidae and provide evidence of their monophyletic origin, suggesting a typical Gondwanaland group. Larvae of P. latipalpis were found 2-3 cm below of the soil surface and associated with larvae of Coleoptera, Lepidoptera, and Diptera in southern Chile.

  7. Across-arc geochemical variations in the Southern Volcanic Zone, Chile (34.5-38.0°S): Constraints on mantle wedge and slab input compositions

    NASA Astrophysics Data System (ADS)

    Jacques, G.; Hoernle, K.; Gill, J.; Hauff, F.; Wehrmann, H.; Garbe-Schönberg, D.; van den Bogaard, P.; Bindeman, I.; Lara, L. E.

    2013-12-01

    Crustal assimilation (e.g. Hildreth and Moorbath, 1988) and/or subduction erosion (e.g. Stern, 1991; Kay et al., 2005) are believed to control the geochemical variations along the northern portion of the Chilean Southern Volcanic Zone. In order to evaluate these hypotheses, we present a comprehensive geochemical data set (major and trace elements and O-Sr-Nd-Hf-Pb isotopes) from Holocene primarily olivine-bearing volcanic rocks across the arc between 34.5°S and 38.0°S, including volcanic front centers from Tinguiririca to Callaqui, the rear arc centers of Infernillo Volcanic Field, Laguna del Maule and Copahue, and extending 300 km into the backarc. We also present an equivalent data set for Chile trench sediments outboard of this profile. The volcanic arc (including volcanic front and rear arc) samples primarily range from basalt to andesite/trachyandesite, whereas the backarc rocks are low-silica alkali basalts and trachybasalts. All samples show some characteristic subduction zone trace element enrichments and depletions, but the backarc samples show the least. Backarc basalts have higher Ce/Pb, Nb/U, Nb/Zr, and Ta/Hf, and lower Ba/Nb and Ba/La, consistent with less of a slab-derived component in the backarc and, consequently, lower degrees of mantle melting. The mantle-like δ18O in olivine and plagioclase phenocrysts (volcanic arc = 4.9-5.6‰ and backarc = 5.0-5.4‰) and lack of correlation between δ18O and indices of differentiation and other isotope ratios, argue against significant crustal assimilation. Volcanic arc and backarc samples almost completely overlap in Sr and Nd isotopic composition. High precision (double-spike) Pb isotope ratios are tightly correlated, precluding significant assimilation of older sialic crust but indicating mixing between a South Atlantic Mid Ocean-Ridge Basalt (MORB) source and a slab component derived from subducted sediments and altered oceanic crust. Hf-Nd isotope ratios define separate linear arrays for the volcanic

  8. Wood burning pollution in southern Chile: PM2.5 source apportionment using CMB and molecular markers.

    PubMed

    Villalobos, Ana M; Barraza, Francisco; Jorquera, Héctor; Schauer, James J

    2017-06-01

    Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; i.e., ambient 24-h PM 2.5 concentrations have exceeded 150 μg/m 3 in the winter season and the top concentration reached 372 μg/m 3 in 2010. Annual mean concentrations have decreased but are still above 30 μg/m 3 . For the very first time, a molecular marker source apportionment of ambient organic carbon (OC) and PM 2.5 was conducted in Temuco. Primary resolved sources for PM 2.5 were wood smoke (37.5%), coal combustion (4.4%), diesel vehicles (3.3%), dust (2.2%) and vegetative detritus (0.7%). Secondary inorganic PM 2.5 (sulfates, nitrates and ammonium) contributed 4.8% and unresolved organic aerosols (generated from volatile emissions from incomplete wood combustion), including secondary organic aerosols, contributed 47.1%. Adding the contributions of unresolved organic aerosols to those from primary wood smoke implies that wood burning is responsible for 84.6% of the ambient PM 2.5 in Temuco. This predominance of wood smoke is ultimately due to widespread poverty and a lack of efficient household heating methods. The government has been implementing emission abatement policies but achieving compliance with ambient air quality standards for PM 2.5 in southern Chile remains a challenge. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Carbon stocks and greenhouse gas balance of an old-growth forest and an anthropogenic peatland in southern Chile

    NASA Astrophysics Data System (ADS)

    Perez-Quezada, J. F.; Brito, C. E.; Valdés, A.; Urrutia, P.

    2016-12-01

    Few studies have reported the effects of deforestation on carbon stocks and greenhouse gas balance in the temperate forests of the southern hemisphere. In some areas of southern Chile, after clear-cut or forest fires occurs a proliferation of Sphagnum moss, generating an anthropogenic type of peatland. We measured the effects of this change on the carbon stocks and the greenhouse gas balance, starting in 2013. Carbon stocks were measured in >30 plots on each site; ecosystem CO2 fluxes were measured continuously using eddy covariance stations; CH4 and N2O fluxes were measured monthly using closed chambers and cavity ring-down spectroscopy technology. Total ecosystem carbon stock was 1,523 Mg ha-1 in the forest and 130 Mg ha-1 in the peatland, representing a 91% difference. Both land use types were found to act as sinks of CO2 (NEE=-1094.2 and -31.9 g CO2 m-2 year-¹ for the forest and peatland, respectively); CH4 was mainly captured in the forest and peatland soils, generating balances of -0.70 and -0.12 g CH₄ m-2 year-¹. N2O fluxes were extremely low, so were considered as null. These results indicate that the greenhouse gas balance moved from -1134.6 to -38.8 g CO2-eq m-2 year-1 when land use changed from forest to anthropogenic peatland. These results provide evidence of the importance of preserving old-growth forests in southern Chile.

  10. Use of high-resolution satellite images for detection of geological structures related to Calerias geothermal field, Chile

    NASA Astrophysics Data System (ADS)

    Arellano-Baeza, A. A.; Urzua, L.

    2011-12-01

    Chile has enormous potential to use the geothermal resources for electric energy generation. The main geothermal fields are located in the Central Andean Volcanic Chain in the North, between the Central valley and the border with Argentina in the center, and in the fault system Liquiñe-Ofqui in the South of the country. High resolution images from the LANDSAT and ASTER satellites have been used to delineate the geological structures related to the Calerias geothermal field located at the northern end of the Southern Volcanic Zone of Chile. It was done by applying the lineament extraction technique developed by authors. These structures have been compared with the distribution of main geological structures obtained in the field. It was found that the lineament density increases in the areas of the major heat flux indicating that the lineament analysis could be a power tool for the detection of faults and joint zones associated to the geothermal fields.

  11. Monitoring the northern Chile megathrust with the Integrated Plate boundary Observatory Chile (IPOC)

    NASA Astrophysics Data System (ADS)

    Schurr, Bernd; Asch, Günter; Cailleau, Beatrice; Diaz, Guillermo Chong; Barrientos, Sergio; Vilotte, Jean-Pierre; Oncken, Onno

    2010-05-01

    The oceanic Nazca plate subducts beneath the continental South American plate by recurrent rupture of large segments of its interface. The resulting earthquakes are among the largest and most frequent on Earth. Along the Chilean and southern Peruvian margin, all sizeable segments have ruptured at least once in the past 150 years for which there exist historic and/or instrumental records. The one segment that is most mature for re-rupture stretches for more than 500 km along the northernmost Chilean coast between roughly -23° and -18° latitude. It last broke in 1877 in a magnitude ~8.5 earthquake, triggering a major Tsunami. From the historical record, it has been known to have a recurrence cycle of approximately 110 years. The adjoining segments to the south and north broke rather recently in 1995 and 2001 in M>8 earthquakes and an M 7.7 earthquake intruded into the southern part of the seismic gap in 2007 between Antofagasto and Tocopilla. This makes northern Chile a unique natural laboratory to observe a subduction megathrust at various stages of its seismic cycle. For that purpose, installation of long-term observatories started in 2006 in a close cooperation of the Universidad de Chile (Santiago, Chile), the Universidad Catolica del Norte (Antofagasta, Chile), the Institut de Physique du Globe de Paris (France), and the GFZ German research Centre for Geosciences (Germany). Currently we are operating 17 modern seismological stations equipped with STS-2 broadband seismometers and accelerometers (EPI sensor). At least two more stations will be installed in the near future. Continuous GPS, tilt, creep, climate and magnetotellurics measurements are complementing the seismological part. A majority of the sites provide data near real-time. We will present results of seismic monitoring including analysis of the 2007 M7.7 Tocopilla earthquake sequence that was recorded during the installation stage of the observatory. We relocated the mainshock and about a one

  12. The International Plate Boundary Observatory Chile (IPOC) in the northern Chile seismic gap

    NASA Astrophysics Data System (ADS)

    Schurr, B.; Asch, A.; Sodoudi, F.; Manzanares, A.; Ritter, O.; Klotz, J.; Chong-Diaz, G.; Barrientos, S.; Villotte, J.-P.; Oncken, O.

    2009-04-01

    Fast convergence between the oceanic Nazca and the continental South American plate is accommodated by recurrent rupture of large segments of the two plates' interface. The resulting earthquakes are among the largest and, for their sizes, most frequent on Earth. Along the Chilean and southern Peruvian margin, all segments have ruptured at least once in the past 150 years for which there exist historic and/or instrumental records. The one segment that is most mature for re-rupture stretches for more than 500 km along the northernmost Chilean coast between roughly -23° and -18° latitude. It last broke in 1877 in a magnitude ~8.8 earthquake, triggering a major Tsunami. From the historical record, it has been known to have a recurrence cycle of approximately 110 years. The adjoining segments to the north and south broke rather recently in 1995 and 2001 in M>8 earthquakes and an M 7.7 earthquake encroached the southern part of the gap in 2007. The IPOC project intends to investigate this segment of the Nazca-South American plate boundary, on which a strong to devastating earthquake is expected to occur within the next years, by monitoring at a variety of time-scales deformation, seismicity, and magnetotelluric fields in the subduction zone at the closing stages of the interseismic cycle before and possibly during occurrence of a big earthquake. For that purpose, installation of long-term observatories in Northern Chile started in 2006 in a close cooperation of the Universidad de Chile (Santiago, Chile), the Universidad Catolica del Norte (Antofagasta, Chile), the Institut de Physique du Globe de Paris (Paris, France), and the German Research Centre for Geosciences (GFZ, Potsdam, Germany). Currently we are operating 14 modern seismological stations equipped with STS-2 broadband seismometers and accelerometers (EPI sensor). At least two more stations will be installed in the near future. To cope with the high resolution and dynamic of the sensors and data acquisition

  13. A remote sensing assessment of the impact of the 2010 Maule, Chile earthquake (Mw 8.8) on the volcanoes of the southern Andes

    NASA Astrophysics Data System (ADS)

    Pritchard, M. E.; Welch, M.; Jay, J.; Button, N.

    2011-12-01

    There are tantalizing, but controversial, indications that great earthquakes affect arc-wide volcanic activity. For example, analysis of historic eruptions at volcanoes of the southern Andes has shown that 3-4 eruptions were likely seismically triggered by Mw > 8 earthquakes in the Chile subduction zone -- particularly the 1906 and 1960 earthquakes (e.g., Watt et al., 2009). However, the 27 February 2010 Mw 8.8 Maule, Chile earthquake that ruptured the subduction zone between the 1960 and 1906 earthquakes does not appear to have triggered 3-4 volcanic eruptions in the same area in the 12 months after the event. In an effort to understand the relation between a large earthquake and volcanic unrest, we use a variety of satellite instruments to look for more subtle (i.e., not leading to eruption), but detectable change in thermal or deformation activity at the volcanoes of the southern Andes after the Maule earthquake and its aftershocks. For all of the volcanoes in the catalog of the Smithsonian Institution (approximately 80), we use nighttime MODIS and ASTER data to assess the thermal activity and ALOS InSAR data to characterize the surface deformation before and after the earthquake. The ALOS InSAR data are not ideal for detecting changes in deformation before and after the earthquake because of the small number of acquisitions in austral summer as well as ionospheric and tropospheric artifacts. We estimate that we could detect deformation > 5 cm/year. Similarly, the ASTER and MODIS data suffer respectively from poor temporal and spatial resolution of thermal anomalies. We update previous InSAR work that identified at least 8 areas of volcanic deformation in the southern Andes related to eruptive processes, subsidence of past lava flows, or surface uplift not associated with an eruption (Fournier et al., 2010). Of greatest interest are the two volcanic areas with the largest deformation signals between 2007-2008 (both > 15 cm/yr in the radar line of sight): Laguna

  14. Paleozoic evolution of active margin basins in the southern Central Andes (northwestern Argentina and northern Chile)

    NASA Astrophysics Data System (ADS)

    Bahlburg, H.; Breitkreuz, C.

    The geodynamic evolution of the Paleozoic continental margin of Gondwana in the region of the southern Central Andes is characterized by the westward progression of orogenic basin formation through time. The Ordovician basin in the northwest Argentinian Cordillera Oriental and Puna originated as an Early Ordovician back-arc basin. The contemporaneous magmatic arc of an east-dipping subduction zone was presumably located in northern Chile. In the back-arc basin, a ca. 3500 meter, fining-up volcaniclastic apron connected to the arc formed during the Arenigian. Increased subsidence in the late Arenigian allowed for the accomodation of large volumes of volcaniclastic turbidites during the Middle Ordovician. Subsidence and sedimentation were caused by the onset of collision between the para-autochthonous Arequipa Massif Terrane (AMT) and the South American margin at the Arenigian-Llanvirnian transition. This led to eastward thrusting of the arc complex over its back-arc basin and, consequently, to its transformation into a marine foreland basin. As a result of thrusting in the west, a flexural bulge formed in the east, leading to uplift and emergence of the Cordillera Oriental shelf during the Guandacol Event at the Arenigian-Llanvirnian transition. The basin fill was folded during the terminal collision of the AMT during the Oclóyic Orogeny (Ashgillian). The folded strata were intruded post-tectonically by the presumably Silurian granitoids of the "Faja Eruptiva de la Puna Oriental." The orogeny led to the formation of the positive area of the Arco Puneño. West of the Arco Puneño, a further marine basin developed during the Early Devonian, the eastern shelf of which occupied the area of the Cordillera Occidental, Depresión Preandina, and Precordillera. The corresponding deep marine turbidite basin was located in the region of the Cordillera de la Costa. Deposition continued until the basin fill was folded in the early Late Carboniferous Toco Orogeny. The basin

  15. Locking of the Chile subduction zone controlled by fluid pressure before the 2010 earthquake

    NASA Astrophysics Data System (ADS)

    Moreno, Marcos; Haberland, Christian; Oncken, Onno; Rietbrock, Andreas; Angiboust, Samuel; Heidbach, Oliver

    2014-04-01

    Constraints on the potential size and recurrence time of strong subduction-zone earthquakes come from the degree of locking between the down-going and overriding plates, in the period between large earthquakes. In many cases, this interseismic locking degree correlates with slip during large earthquakes or is attributed to variations in fluid content at the plate interface. Here we use geodetic and seismological data to explore the links between pore-fluid pressure and locking patterns at the subduction interface ruptured during the magnitude 8.8 Chile earthquake in 2010. High-resolution three-dimensional seismic tomography reveals variations in the ratio of seismic P- to S-wave velocities (Vp/Vs) along the length of the subduction-zone interface. High Vp/Vs domains, interpreted as zones of elevated pore-fluid pressure, correlate spatially with parts of the plate interface that are poorly locked and slip aseismically. In contrast, low Vp/Vs domains, interpreted as zones of lower pore-fluid pressure, correlate with locked parts of the plate interface, where unstable slip and earthquakes occur. Variations in pore-fluid pressure are caused by the subduction and dehydration of a hydrothermally altered oceanic fracture zone. We conclude that variations in pore-fluid pressure at the plate interface control the degree of interseismic locking and therefore the slip distribution of large earthquake ruptures.

  16. Exploring the Genomic Traits of Non-toxigenic Vibrio parahaemolyticus Strains Isolated in Southern Chile

    PubMed Central

    Castillo, Daniel; Pérez-Reytor, Diliana; Plaza, Nicolás; Ramírez-Araya, Sebastián; Blondel, Carlos J.; Corsini, Gino; Bastías, Roberto; Loyola, David E.; Jaña, Víctor; Pavez, Leonardo; García, Katherine

    2018-01-01

    Vibrio parahaemolyticus is the leading cause of seafood-borne gastroenteritis worldwide. As reported in other countries, after the rise and fall of the pandemic strain in Chile, other post-pandemic strains have been associated with clinical cases, including strains lacking the major toxins TDH and TRH. Since the presence or absence of tdh and trh genes has been used for diagnostic purposes and as a proxy of the virulence of V. parahaemolyticus isolates, the understanding of virulence in V. parahaemolyticus strains lacking toxins is essential to detect these strains present in water and marine products to avoid possible food-borne infection. In this study, we characterized the genome of four environmental and two clinical non-toxigenic strains (tdh-, trh-, and T3SS2-). Using whole-genome sequencing, phylogenetic, and comparative genome analysis, we identified the core and pan-genome of V. parahaemolyticus of strains of southern Chile. The phylogenetic tree based on the core genome showed low genetic diversity but the analysis of the pan-genome revealed that all strains harbored genomic islands carrying diverse virulence and fitness factors or prophage-like elements that encode toxins like Zot and RTX. Interestingly, the three strains carrying Zot-like toxin have a different sequence, although the alignment showed some conserved areas with the zot sequence found in V. cholerae. In addition, we identified an unexpected diversity in the genetic architecture of the T3SS1 gene cluster and the presence of the T3SS2 gene cluster in a non-pandemic environmental strain. Our study sheds light on the diversity of V. parahaemolyticus strains from the southern Pacific which increases our current knowledge regarding the global diversity of this organism. PMID:29472910

  17. [Eating habits and subjective well-being among university students in southern Chile].

    PubMed

    Schnettler, Berta; Denegri, Marianela; Miranda, Horacio; Sepúlveda, José; Orellana, Ligia; Paiva, Galo; Grunert, Klaus G

    2013-11-01

    To distinguish typologies of university students in southern Chile on the basis of their level of satisfaction with life and food-related life, and to characterize them according to their eating habits inside and outside the place of residence, aspects associated with health and demographic characteristics. A structured questionnaire was applied to a non-probabilistic sample of 347 students at the Universidad de La Frontera, Temuco, Chile. The instruments for collecting information included the SWLS (Satisfaction with Life Scale), SWFL (Satisfaction with Food-related Life) and the HRQOL (Health-related Quality of Life Index). Questions were asked about eating habits inside and outside the place of residence, weight and approximate height, and variables for demographic classification. Using a cluster analysis, three student typologies were distinguished, with significant differences in the SWLS and SWFL scores. The typologies differed in the number of days affected by emotional health problems, classification of their nutritional status (BMI), self-perception of their state of health, importance of food to personal well-being, place of residence during the period of studies, frequency of eating in the place of residence and frequency of meals at inconvenient times. The possibility of living with parents during the period of university studies is associated with better eating habits, better emotional health and self-perception of health, lower prevalence of overweight and obesity, and greater satisfaction with the life and food-related life. Copyright AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

  18. Historical and recent large megathrust earthquakes in Chile

    NASA Astrophysics Data System (ADS)

    Ruiz, S.; Madariaga, R.

    2018-05-01

    Recent earthquakes in Chile, 2014, Mw 8.2 Iquique, 2015, Mw 8.3 Illapel and 2016, Mw 7.6 Chiloé have put in evidence some problems with the straightforward application of ideas about seismic gaps, earthquake periodicity and the general forecast of large megathrust earthquakes. In northern Chile, before the 2014 Iquique earthquake 4 large earthquakes were reported in written chronicles, 1877, 1786, 1615 and 1543; in North-Central Chile, before the 2015 Illapel event, 3 large earthquakes 1943, 1880, 1730 were reported; and the 2016 Chiloé earthquake occurred in the southern zone of the 1960 Valdivia megathrust rupture, where other large earthquakes occurred in 1575, 1737 and 1837. The periodicity of these events has been proposed as a good long-term forecasting. However, the seismological aspects of historical Chilean earthquakes were inferred mainly from old chronicles written before subduction in Chile was discovered. Here we use the original description of earthquakes to re-analyze the historical archives. Our interpretation shows that a-priori ideas, like seismic gaps and characteristic earthquakes, influenced the estimation of magnitude, location and rupture area of the older Chilean events. On the other hand, the advance in the characterization of the rheological aspects that controlled the contact between Nazca and South-American plate and the study of tsunami effects provide better estimations of the location of historical earthquakes along the seismogenic plate interface. Our re-interpretation of historical earthquakes shows a large diversity of earthquakes types; there is a major difference between giant earthquakes that break the entire plate interface and those of Mw 8.0 that only break a portion of it.

  19. Community response of zooplankton to oceanographic changes (2002-2012) in the central/southern upwelling system of Chile

    NASA Astrophysics Data System (ADS)

    Medellín-Mora, Johanna; Escribano, Ruben; Schneider, Wolfgang

    2016-03-01

    A 10-year time series (2002-2012) at Station 18 off central/southern Chile allowed us to study variations in zooplankton along with interannual variability and trends in oceanographic conditions. We used an automated analysis program (ZooImage) to assess changes in the mesozooplankton size structure and the composition of the taxa throughout the entire community. Oceanographic conditions changed over the decade: the water column became less stratified, more saline, and colder; the mixed layer deepened; and the oxygen minimum zone became shallower during the second half of the time series (2008-2012) in comparison with the first period (2002-2007). Both the size structure and composition of the zooplankton were significantly associated with oceanographic changes. Taxonomic and size diversity of the zooplankton community increased to the more recent period. For the second period, small sized copepods (<1 mm) decreased in abundance, being replaced by larger sized (>1.5 mm) and medium size copepods (1-1.5 mm), whereas euphausiids, decapod larvae, appendicularian and ostracods increased their abundance during the second period. These findings indicated that the zooplankton community structure in this eastern boundary ecosystem was strongly influenced by variability of the upwelling process. Thus, climate-induced forcing of upwelling trends can alter the zooplankton community in this highly productive region with potential consequences for the ecosystem food web.

  20. Microbial eukaryote diversity in the marine oxygen minimum zone off northern Chile.

    PubMed

    Parris, Darren J; Ganesh, Sangita; Edgcomb, Virginia P; DeLong, Edward F; Stewart, Frank J

    2014-01-01

    Molecular surveys are revealing diverse eukaryotic assemblages in oxygen-limited ocean waters. These communities may play pivotal ecological roles through autotrophy, feeding, and a wide range of symbiotic associations with prokaryotes. We used 18S rRNA gene sequencing to provide the first snapshot of pelagic microeukaryotic community structure in two cellular size fractions (0.2-1.6 μm, >1.6 μm) from seven depths through the anoxic oxygen minimum zone (OMZ) off northern Chile. Sequencing of >154,000 amplicons revealed contrasting patterns of phylogenetic diversity across size fractions and depths. Protist and total eukaryote diversity in the >1.6 μm fraction peaked at the chlorophyll maximum in the upper photic zone before declining by ~50% in the OMZ. In contrast, diversity in the 0.2-1.6 μm fraction, though also elevated in the upper photic zone, increased four-fold from the lower oxycline to a maximum at the anoxic OMZ core. Dinoflagellates of the Dinophyceae and endosymbiotic Syndiniales clades dominated the protist assemblage at all depths (~40-70% of sequences). Other protist groups varied with depth, with the anoxic zone community of the larger size fraction enriched in euglenozoan flagellates and acantharean radiolarians (up to 18 and 40% of all sequences, respectively). The OMZ 0.2-1.6 μm fraction was dominated (11-99%) by Syndiniales, which exhibited depth-specific variation in composition and total richness despite uniform oxygen conditions. Metazoan sequences, though confined primarily to the 1.6 μm fraction above the OMZ, were also detected within the anoxic zone where groups such as copepods increased in abundance relative to the oxycline and upper OMZ. These data, compared to those from other low-oxygen sites, reveal variation in OMZ microeukaryote composition, helping to identify clades with potential adaptations to oxygen-depletion.

  1. Microbial eukaryote diversity in the marine oxygen minimum zone off northern Chile

    PubMed Central

    Parris, Darren J.; Ganesh, Sangita; Edgcomb, Virginia P.; DeLong, Edward F.; Stewart, Frank J.

    2014-01-01

    Molecular surveys are revealing diverse eukaryotic assemblages in oxygen-limited ocean waters. These communities may play pivotal ecological roles through autotrophy, feeding, and a wide range of symbiotic associations with prokaryotes. We used 18S rRNA gene sequencing to provide the first snapshot of pelagic microeukaryotic community structure in two cellular size fractions (0.2–1.6 μm, >1.6 μm) from seven depths through the anoxic oxygen minimum zone (OMZ) off northern Chile. Sequencing of >154,000 amplicons revealed contrasting patterns of phylogenetic diversity across size fractions and depths. Protist and total eukaryote diversity in the >1.6 μm fraction peaked at the chlorophyll maximum in the upper photic zone before declining by ~50% in the OMZ. In contrast, diversity in the 0.2–1.6 μm fraction, though also elevated in the upper photic zone, increased four-fold from the lower oxycline to a maximum at the anoxic OMZ core. Dinoflagellates of the Dinophyceae and endosymbiotic Syndiniales clades dominated the protist assemblage at all depths (~40–70% of sequences). Other protist groups varied with depth, with the anoxic zone community of the larger size fraction enriched in euglenozoan flagellates and acantharean radiolarians (up to 18 and 40% of all sequences, respectively). The OMZ 0.2–1.6 μm fraction was dominated (11–99%) by Syndiniales, which exhibited depth-specific variation in composition and total richness despite uniform oxygen conditions. Metazoan sequences, though confined primarily to the 1.6 μm fraction above the OMZ, were also detected within the anoxic zone where groups such as copepods increased in abundance relative to the oxycline and upper OMZ. These data, compared to those from other low-oxygen sites, reveal variation in OMZ microeukaryote composition, helping to identify clades with potential adaptations to oxygen-depletion. PMID:25389417

  2. Seismic and Aseismic Slip Surrounding the 2014 Mw 8.2 Pisagua (Chile) rupture

    NASA Astrophysics Data System (ADS)

    Shrivastava, M. N.; Gonzalez, G.; Salazar, P.; Moreno, M.; Baez, J. C.

    2017-12-01

    On April 1 2014, the Mw 8.2 Pisagua earthquake occurred in a part of standing seismic gap northern Chile. We inverted the cGPS time series for coseismic slip of mainshock and big aftershock Mw 7.6 on April 3, 2014 individually. The big aftershock Mw 7.6 occurred in south of the coseismic slip region of main shock. The coseismic slip model suggest that it has an asperity of single patch has slipped during the Pisagua earthquake and confined in the inter-seismically highly locked region. It seems that Iquique ridge fragmented northern Chile seismic gap region. It could provide small asperity, which has broken partial discretely. The spatial distribution of afterslip from the inversion of cGPS time series is consistent and appears in two patches to cover north and south of the mainshock coseismic slip patch. The afterslip patches suggest that the maximum cumulative afterslip 50cm is located at ˜19.0°S to the north of the mainshock rupture zone and down dip 38km. The estimated postseismic moment released in the first 60-days of afterslip is equivalent to an earthquake of Mw 7.43. The 60-days 306 aftershocks (Mw>3.0) has confined in the mainshock slip and southern afterslip region. With the afterslip model 60-days, it concludes that aftershocks distribution not only depends on Coulomb stress changes but also the locking degree of region/heterogeneity of the plate interface. Seismic slip is restricted in the southern locked region, but aseismic slip in the northern low locking region. It means the southern portion of the northern Chile is still non-ruptured. It can break with great megathrust earthquake in future. Therefore, it is essential to scrutinize the slip deficit by using a space geodetic technique to assess earthquake potential. The northern patch of the afterslip is purely aseismic as stable sliding confined in the low locking region, however the southern patch afterslip seismically as unstable stick-slip dominating. It suggests that afterslip illuminates the

  3. Floating marine debris in fjords, gulfs and channels of southern Chile.

    PubMed

    Hinojosa, Iván A; Thiel, Martin

    2009-08-01

    Floating marine debris (FMD) is reported from all oceans. The bulk of FMD are plastics, which due to their longevity cause multiple negative impacts on wildlife and environment. Identifying the origins of FMD (land- or sea-based) is important to take the necessary steps to diminish their abundance. Using ship surveys we examined the abundance, composition and distribution of FMD during the years 2002-2005 in the fjords, gulfs and channels of southern Chile. Abundances of FMD were relatively high compared with other studies, ranging from 1 to 250 items km(-2). The majority (approximately 80%) of FMD was composed of styrofoam (expanded polystyrene), plastic bags and plastic fragments. Styrofoam, which is intensively used as flotation device by mussel farms, was very abundant in the northern region but rarely occurred in the southern region of the study area. Food sacks from salmon farms were also most common in the northern region, where approximately 85% of the total Chilean mussel and salmon harvest is produced. Plastic bags, which could be from land- or sea-based sources, were found throughout the entire study area. Our results indicate that sea-based activities (mussel farming and salmon aquaculture) are responsible for most FMD in the study area. In order to reduce FMDs in the environment, in addition to stronger legislation and identification of potential sources, we suggest environmental education programs and we encourage public participation (e.g. in beach surveys and clean-ups).

  4. Enrichments of the mantle sources beneath the Southern Volcanic Zone (Andes) by fluids and melts derived from abraded upper continental crust

    NASA Astrophysics Data System (ADS)

    Holm, Paul Martin; Søager, Nina; Dyhr, Charlotte Thorup; Nielsen, Mia Rohde

    2014-05-01

    Mafic basaltic-andesitic volcanic rocks from the Andean Southern Volcanic Zone (SVZ) exhibit a northward increase in crustal components in primitive arc magmas from the Central through the Transitional and Northern SVZ segments. New elemental and Sr-Nd-high-precision Pb isotope data from the Quaternary arc volcanic centres of Maipo (NSVZ) and Infernillo and Laguna del Maule (TSVZ) are argued to reflect mainly their mantle source and its melting. For the C-T-NSVZ, we identify two types of source enrichment: one, represented by Antuco in CSVZ, but also present northward along the arc, was dominated by fluids which enriched a pre-metasomatic South Atlantic depleted MORB mantle type asthenosphere. The second enrichment was by melts having the characteristics of upper continental crust (UCC), distinctly different from Chile trench sediments. We suggest that granitic rocks entered the source mantle by means of subduction erosion in response to the northward increasingly strong coupling of the converging plates. Both types of enrichment had the same Pb isotope composition in the TSVZ with no significant component derived from the subducting oceanic crust. Pb-Sr-Nd isotopes indicate a major crustal compositional change at the southern end of the NSVZ. Modelling suggests addition of around 2 % UCC for Infernillo and 5 % for Maipo.

  5. Coastal evidence for Holocene subduction-zone earthquakes and tsunamis in central Chile

    USGS Publications Warehouse

    Dure, Tina; Cisternas, Marco; Horton, Benjamin; Ely, Lisa; Nelson, Alan R.; Wesson, Robert L.; Pilarczyk, Jessica

    2015-01-01

    The ∼500-year historical record of seismicity along the central Chile coast (30–34°S) is characterized by a series of ∼M 8.0–8.5 earthquakes followed by low tsunamis (<4 m) occurring on the megathrust about every 80 years. One exception is the AD 1730 great earthquake (M 9.0–9.5) and high tsunami (>10 m), but the frequency of such large events is unknown. We extend the seismic history of central Chile through a study of a lowland stratigraphic sequence along the metropolitan coast north of Valparaíso (33°S). At this site, higher relative sea level during the mid Holocene created a tidal marsh and the accommodation space necessary for sediment that preserves earthquake and tsunami evidence. Within this 2600-yr-long sequence, we traced six laterally continuous sand beds probably deposited by high tsunamis. Plant remains that underlie the sand beds were radiocarbon dated to 6200, 5600, 5000, 4400, 3800, and 3700 cal yr BP. Sediment properties and diatom assemblages of the sand beds—for example, anomalous marine planktonic diatoms and upward fining of silt-sized diatom valves—point to a marine sediment source and high-energy deposition. Grain-size analysis shows a strong similarity between inferred tsunami deposits and modern coastal sediment. Upward fining sequences characteristic of suspension deposition are present in five of the six sand beds. Despite the lack of significant lithologic changes between the sedimentary units under- and overlying tsunami deposits, we infer that the increase in freshwater siliceous microfossils in overlying units records coseismic uplift concurrent with the deposition of five of the sand beds. During our mid-Holocene window of evidence preservation, the mean recurrence interval of earthquakes and tsunamis is ∼500 years. Our findings imply that the frequency of historical earthquakes in central Chile is not representative of the greatest earthquakes and tsunamis that the central Chilean subduction zone has

  6. Mass-specific respiration of mesozooplankton and its role in the maintenance of an oxygen-deficient ecological barrier (BEDOX) in the upwelling zone off Chile upon presence of a shallow oxygen minimum zone

    NASA Astrophysics Data System (ADS)

    Donoso, Katty; Escribano, Ruben

    2014-01-01

    A shallow oxygen minimum zone (OMZ) in the coastal upwelling zone off Chile may vertically confine most zooplankton to a narrow (< 50 m) upper layer. From laboratory experiments, we estimated oxygen consumption of the mesozooplankton community obtained in Bay of Mejillones, northern Chile (23°S) in May 2010, December 2010 and August 2011. Mass-specific respiration rates were in the range of 8.2-24.5 μmol O2 mg dry mass- 1 day- 1, at an average temperature of 12 °C. Estimates of the mesozooplankton biomass in the water column indicated that its aerobic respiration may remove daily a maximum of about 20% of oxygen available at the base of the oxycline. Since previous work indicates that zooplankton aggregate near the base of the oxycline, the impact of aerobic respiration on oxygen content might be even stronger at this depth. Mesozooplankton respiration, along with community respiration by microorganisms near the base of the oxycline and a strongly stratified condition (limiting vertical flux of O2), are suggested as being critical factors causing and maintaining a persistent subsurface oxygen-deficient ecological barrier (BEDOX) in the upwelling zone. This BEDOX layer can have a major role in affecting and regulating zooplankton distribution and their dynamics in the highly productive coastal upwelling zone of the Humboldt Current System.

  7. Expanding Geophysical and Geochemical Investigation of Causes of Extraordinary Unrest at the Laguna del Maule (Rhyolitic) Volcanic Field, Southern Andes, Chile

    NASA Astrophysics Data System (ADS)

    Singer, B. S.

    2014-12-01

    The Laguna del Maule Volcanic Field, Chile, includes an unusually large and recent concentration of silicic eruptions. Since 2007 the crust here has been inflating at an astonishing rate of 25 cm/yr. Findings thus far lead to the hypothesis that the silicic vents have tapped an extensive layer of crystal-poor, rhyolitic melt that began to form atop a magmatic mush zone that was established by ~20 ka with a renewed phase of rhyolite eruptions during the Holocene. Modeling of surface deformation, magnetotelluric data, and gravity changes suggest that magma is currently intruding at a depth of ~5 km. Swarms of volcano-tectonic and long period earthquakes, mostly of M < 2, have occurred beneath the most recent rhyolite coulees on the southwestern and southern margins of the 20 km diameter ring of silicic vents. With support from the US NSF and the Chilean government (SERNAGEOMIN and OVDAS) we are seizing the unique opportunity to investigate, over the next 5 years, the dynamics of this large rhyolitic system while magma migration, reservoir growth, and crustal deformation are actively underway. This collaboration involves scientists and students at: University of Wisconsin-Madison, Georgia Tech, Cornell, University of Alberta, Simon Fraser University, University of Chile-Santiago, CONICET/University of San Juan-Argentina, Nanyang Technological University-Singapore, SERNAGEOMIN, OVDAS, USGS, and SEGEMAR-Argentina. Team members will be introduced in this presentation. Our approach includes augmenting the OVDAS array of 6 permanent seisic stations with 40 additional instruments to conduct tomographic, receiver function and ambient noise studies. We continue to collect 4-D gravity data from 37 stations. Surface deformation is monitored via cGPS at 5 permanent receivers and InSAR data. A magnetotelluric survey across the Andes at 36o S is planned. Geochemical studies include mineral zoning and U-Th disequilibrium of zircons to constrain the timing of magma intrusion and

  8. Herd-level prevalence of Map infection in dairy herds of southern Chile determined by culture of environmental fecal samples and bulk-tank milk qPCR.

    PubMed

    Kruze, J; Monti, G; Schulze, F; Mella, A; Leiva, S

    2013-09-01

    Paratuberculosis, an infectious disease of domestic and wild ruminants caused by Mycobacterium avium subsp. paratuberculosis (Map), is an economically important disease in dairy herds worldwide. In Chile the disease has been reported in domestic and wildlife animals. However, accurate and updated estimations of the herd-prevalence in cattle at national or regional level are not available. The objectives of this study were to determine the herd-level prevalence of dairy herds with Map infected animals of Southern Chile, based on two diagnostic tests: culture of environmental fecal samples and bulk-tank milk qPCR. Two composite environmental fecal samples and one bulk-tank milk sample were collected during September 2010 and September 2011 from 150 dairy farms in Southern Chile. Isolation of Map from environmental fecal samples was done by culture of decontaminated samples on a commercial Herrold's Egg Yolk Medium (HEYM) with and without mycobactin J. Suspicious colonies were confirmed to be Map by conventional IS900 PCR. Map detection in bulk-tank milk samples was done by real time IS900 PCR assay. PCR-confirmed Map was isolated from 58 (19.3%) of 300 environmental fecal samples. Holding pens and manure storage lagoons were the two more frequent sites found positive for Map, representing 35% and 33% of total positive samples, respectively. However, parlor exits and cow alleyways were the two sites with the highest proportion of positive samples (40% and 32%, respectively). Herd prevalence based on environmental fecal culture was 27% (true prevalence 44%) compared to 49% (true prevalence 87%) based on bulk-tank milk real time IS900 PC. In both cases herd prevalence was higher in large herds (>200 cows). These results confirm that Map infection is wide spread in dairy herds in Southern Chile with a rough herd-level prevalence of 28-100% depending on the herd size, and that IS900 PCR on bulk-tank milk samples is more sensitive than environmental fecal culture to detect

  9. Distribution of siphonophores, chaetognaths, euphausiids and oceanographic conditions in the fjords and channels of southern Chile

    NASA Astrophysics Data System (ADS)

    Palma, Sergio; Silva, Nelson

    2004-03-01

    Interior waters of the fjords and channels of southern Chile (41.5°S-56°S) receive inputs of Subantarctic Water, Equatorial Subsuperficial Water and Western Pacific Subsurface Water from the adjacent Pacific Ocean by means of numerous connecting channels that lead inward from the ocean margin. These waters become mixed in the interior zone with freshwater from precipitation, river flow, and meltwater from cordilleran glaciers. A two-layered positive estuarine circulation becomes established, with a superficial layer having a net movement towards the adjacent ocean, and a deep layer with net movement towards the fjords. The biomass of the interior waters is composed principally of planktonic crustaceans (copepods and euphausiids), chaetognaths, and gelatinous carnivores. In a southerly direction, decreases are observed in biomass, in relative abundance, and in species diversity of siphonophores, chaetognaths, and euphausiids. Only a few species have been able to adapt successfully to the extreme oceanographic conditions typical of the region, reflected in dominant monospecific populations such as Muggiaea atlantica, Sagitta tasmanica, and Euphausia vallentini. The zooplankton fauna of interior waters, characterized by its low degree of specific richness, is made up of a mixture of species typical of Subantarctic Water (Sagitta tasmanica, S. decipiens, Euphausia lucens, Nematoscelis megalops, Thysanoessa gregaria), antarctic water (Pyrosthephos vanhoeffeni, Dimophyes arctica, Sagitta marri, S. gazellae, Eukrohnia hamata, E. bathyantarctica, Euphausia vallentini), temperate and warm epipelagic waters (Eudoxoides spiralis, Lensia conoidea, Chelophyes appendiculata, Muggiaea atlantica, Sphaeronectes gracilis, S. fragilis, Abylopsis tetragona, Sagitta enflata), and mesopelagic water (Physophora hydrostatica, Stylocheiron maximum, Vogtia pentacantha, V. serrata).

  10. The Araucanian Indian in Chile. IWGIA Document 20.

    ERIC Educational Resources Information Center

    Berdichewsky, Bernardo

    One of the larger of the native peoples of South America, the Araucanians include different ethnic subgroups, some of which are now extinct. Once geographically spread extensively over the southern cone of South America, at present they are reduced to only two closely related groups: (1) the Mapuche of southern Chile, the largest one; and (2) the…

  11. Subduction zone slip variability during the last millennium, south-central Chile

    USGS Publications Warehouse

    Dura, Tina; Horton, Benjamin P.; Cisternas, Macro; Ely, Lisa L; Hong, Isabel; Nelson, Alan R.; Wesson, Robert L.; Pilarczyk, Jessica E.; Parnell, Andrew C.; Nikitina, Daria

    2017-01-01

    The Arauco Peninsula (37°-38°S) in south-central Chile has been proposed as a possible barrier to the along-strike propagation of megathrust ruptures, separating historical earthquakes to the south (1960 AD 1837, 1737, and 1575) and north (2010 AD, 1835, 1751, 1657, and 1570) of the peninsula. However, the 2010 (Mw 8.8) earthquake propagated into the Arauco Peninsula, re-rupturing part of the megathrust that had ruptured only 50 years earlier during the largest subduction zone earthquake in the instrumental record (Mw 9.5). To better understand long-term slip variability in the Arauco Peninsula region, we analyzed four coastal sedimentary sections from two sites (Tirúa, 38.3°S and Quidico, 38.1°S) located within the overlap of the 2010 and 1960 ruptures to reconstruct a ∼600-year record of coseismic land-level change and tsunami inundation. Stratigraphic, lithologic, and diatom results show variable coseismic land-level change coincident with tsunami inundation of the Tirúa and Quidico marshes that is consistent with regional historical accounts of coseismic subsidence during earthquakes along the Valdivia portion of the subduction zone (1960 AD and 1575) and coseismic uplift during earthquakes along the Maule portion of the subduction zone (2010 AD, 1835, 1751). In addition, we document variable coseismic land-level change associated with three new prehistoric earthquakes and accompanying tsunamis in 1470–1570 AD, 1425–1455, and 270–410. The mixed record of coseismic subsidence and uplift that we document illustrates the variability of down-dip and lateral slip distribution at the overlap of the 2010 and 1960 ruptures, showing that ruptures have repeatedly propagated into, but not through the Arauco Peninsula and suggesting the area has persisted as a long-term impediment to slip through at least seven of the last megathrust earthquakes (∼600 years).

  12. Subduction zone slip variability during the last millennium, south-central Chile

    NASA Astrophysics Data System (ADS)

    Dura, Tina; Horton, Benjamin P.; Cisternas, Marco; Ely, Lisa L.; Hong, Isabel; Nelson, Alan R.; Wesson, Robert L.; Pilarczyk, Jessica E.; Parnell, Andrew C.; Nikitina, Daria

    2017-11-01

    The Arauco Peninsula (37°-38°S) in south-central Chile has been proposed as a possible barrier to the along-strike propagation of megathrust ruptures, separating historical earthquakes to the south (1960 AD 1837, 1737, and 1575) and north (2010 AD, 1835, 1751, 1657, and 1570) of the peninsula. However, the 2010 (Mw 8.8) earthquake propagated into the Arauco Peninsula, re-rupturing part of the megathrust that had ruptured only 50 years earlier during the largest subduction zone earthquake in the instrumental record (Mw 9.5). To better understand long-term slip variability in the Arauco Peninsula region, we analyzed four coastal sedimentary sections from two sites (Tirúa, 38.3°S and Quidico, 38.1°S) located within the overlap of the 2010 and 1960 ruptures to reconstruct a ∼600-year record of coseismic land-level change and tsunami inundation. Stratigraphic, lithologic, and diatom results show variable coseismic land-level change coincident with tsunami inundation of the Tirúa and Quidico marshes that is consistent with regional historical accounts of coseismic subsidence during earthquakes along the Valdivia portion of the subduction zone (1960 AD and 1575) and coseismic uplift during earthquakes along the Maule portion of the subduction zone (2010 AD, 1835, 1751). In addition, we document variable coseismic land-level change associated with three new prehistoric earthquakes and accompanying tsunamis in 1470-1570 AD, 1425-1455, and 270-410. The mixed record of coseismic subsidence and uplift that we document illustrates the variability of down-dip and lateral slip distribution at the overlap of the 2010 and 1960 ruptures, showing that ruptures have repeatedly propagated into, but not through the Arauco Peninsula and suggesting the area has persisted as a long-term impediment to slip through at least seven of the last megathrust earthquakes (∼600 years).

  13. Earthquake hazards on the cascadia subduction zone.

    PubMed

    Heaton, T H; Hartzell, S H

    1987-04-10

    Large subduction earthquakes on the Cascadia subduction zone pose a potential seismic hazard. Very young oceanic lithosphere (10 million years old) is being subducted beneath North America at a rate of approximately 4 centimeters per year. The Cascadia subduction zone shares many characteristics with subduction zones in southern Chile, southwestern Japan, and Colombia, where comparably young oceanic lithosphere is also subducting. Very large subduction earthquakes, ranging in energy magnitude (M(w)) between 8 and 9.5, have occurred along these other subduction zones. If the Cascadia subduction zone is also storing elastic energy, a sequence of several great earthquakes (M(w) 8) or a giant earthquake (M(w) 9) would be necessary to fill this 1200-kilometer gap. The nature of strong ground motions recorded during subduction earthquakes of M(w) less than 8.2 is discussed. Strong ground motions from even larger earthquakes (M(w) up to 9.5) are estimated by simple simulations. If large subduction earthquakes occur in the Pacific Northwest, relatively strong shaking can be expected over a large region. Such earthquakes may also be accompanied by large local tsunamis.

  14. Deep resistivity sounding studies in detecting shear zones: A case study from the southern granulite terrain of India

    NASA Astrophysics Data System (ADS)

    Singh, S. B.; Stephen, Jimmy

    2006-10-01

    The resistivity signatures of the major crustal scale shear zones that dissect the southern granulite terrain (SGT) of South India into discrete geological fragments have been investigated. Resistivity structures deduced from deep resistivity sounding measurements acquired with a 10 km long Schlumberger spreads yield significant insights into the resistivity distribution within the E-W trending shear system comprising the Moyar-Bhavani-Salem-Attur shear zone (MBSASZ) and Palghat-Cauvery shear zone (PCSZ). Vertical and lateral extensions of low resistivity features indicate the possible existence of weak zones at different depths throughout the shear zones. The MBSASZ characterized by very low resistivity in its deeper parts (>2500 m), extends towards the south with slightly higher resistivities to encompass the PCSZ. A major resistivity transition between the northern and southern parts is evident in the two-dimensional resistivity images. The northern Archaean granulite terrain exhibits a higher resistivity than the southern Neoproterozoic granulite terrain. Though this resistivity transition is not clear at greater depths, the extension of low resistivity zones has been well manifested. It is speculated here that a network of crustal scale shear zones in the SGT may have influenced the strength of the lithosphere.

  15. Post-earthquake coastal evolution and recovery of an embayed beach in central-southern Chile

    NASA Astrophysics Data System (ADS)

    Martínez, Carolina; Rojas, Daniel; Quezada, Matías; Quezada, Jorge; Oliva, Ricardo

    2015-12-01

    Earthquakes and tsunamis are significant factors for change along active margin shores, and influence coastal evolution. The Chilean coast was affected in 2010 by a subduction earthquake with a magnitude of Mw 8.8 and also by a trans-Pacific tsunami, which generated violent geomorphologic changes and damaged homes. Following these events, the magnitude of the changes which affect Chile's central-southern coast (37°S) and the role of subduction earthquakes in coastal evolution on a historical scale were investigated. At Lebu bay (an embayed beach) data were generated for variations in time and space along the shoreline, topographical and bathymetric changes in the bay, and for morphodynamic littoral processes. Logarithmic and parabolic models were applied to the shoreline along with map overlays in order to determine changes. The shoreline processes were analyzed based on statistics for waves, tides and sediment transport for pre- and post-tsunami conditions. An average accretion rate of 2.80 m/year (1984-2010) was established for the shoreline, with a strong trend towards accretion in the last 30 years. A parabolic function best represented the general form of the shoreline, although the presence of a river in the concave zone affected the fit in this sector. Two factors controlled historical changes on the beach: one of anthropic origin in addition to the earthquake and tsunami on February 27th, 2010. The post-earthquake recovery was fast, and currently the beach is in a stable condition despite the inter-seismic subsidence process previous to the event. This coastal system showed a high resilience in the face of coastal geomorphological changes induced by high-impact natural disturbances. However, the opposite occurred in relation to changes induced by anthropogenic disturbances.

  16. Spatial and temporal variability of chlorophyll and primary productivity in surface waters of southern Chile (41.5 43° S)

    NASA Astrophysics Data System (ADS)

    Iriarte, J. L.; González, H. E.; Liu, K. K.; Rivas, C.; Valenzuela, C.

    2007-09-01

    The southern fjord region of Chile is a unique ecosystem characterized by complex marine-terrestrial-atmospheric interactions that result in high biological production. Since organic nitrogen from terrestrial and atmospheric compartments is highly significant in this region (>40%), as is the low NO 3:PO 4 ratio in surface waters, it is suggested that fertilization from inorganic and organic nitrogen sources has a strong influence on both phytoplankton biomass/primary production and harmful algae bloom dynamics. The data presented in this paper provide an opportunity to improve our knowledge of phytoplankton dynamics on temporal and spatial mesoscales. Ocean color data from NASA (SeaWiFS) for chlorophyll and primary production estimates and in situ surface measurement of inorganic nutrients, phytoplankton biomass, and primary productivity revealed that the coastal waters of southern Chile have a classical spring and autumn chlorophyll bloom cycle in which primary production is co-limited by strong seasonal changes in light and nitrate. During spring blooms, autotrophic biomass (such as chlorophyll a, Chl- a) and primary production estimates reached 25 mg Chl- a m -3 and 23 mg C m -3 h -1, respectively, and micro-phytoplankton accounted for a significant portion of the biomass (60%) in spring. The contribution of phytoplankton size classes to total chlorophyll a revealed the dominance of nanoplankton (>50%) in winter and post-bloom periods (<1.0 mg Chl- a m -3).

  17. Climate change impact on hydroclimate regimes and extremes over Andean basins in the central-southern Chile

    NASA Astrophysics Data System (ADS)

    Bozkurt, Deniz; Rojas, Maisa; Valdivieso, Jonás; Falvey, Mark

    2015-04-01

    We have assessed the impact of projected increases in temperature and decreased precipitation on variability and potential changes in hydroclimate regimes and extremes over Andean basins in the central-southern Chile (~30-40S). The altitude of the southern Andes in the study area has an average altitude of 5000 m in the north that decreases to 3000 m at the southern edge. Climatically the region has a Mediterranean-like climate with mainly winter precipitation that gradually increases southwards, from around 300 mm/yr to 1000 mm/yr. The region is home to most of the population in Chile (~10 mil. inhabitants), it has fertile and productive agriculture land, as well as hydro-electrical power plants. During the 20th Century the region has experienced a decreasing precipitation trend imbedded in important interannual and decadal scale variability. We have used gridded observed daily precipitation and temperatures to drive and validate the VIC macro-scale model over the region of interest at 0.25 x 0.25 degree resolution. Historical (1960-2005) and projected (RCP8.5, 2006-2099) daily precipitation and temperatures from 28 CMIP5 models are adjusted via a transfer function based on the gridded observed daily precipitation and temperature data. Adjusted time series are then used to drive the VIC model in order to present climate change projections. The hydrological model simulations foresee that drying is robust in the models and total annual runoff will decrease in the future (40-45% by the end of the century). Center timing of runoff tends to shift to earlier days (3-5 weeks by the end of the century). In some areas over the Andes winter runoff is projected to increase due to upward movement of zero isotherm. Moreover, reductions in the amount of snowpack and accelerated snowmelt lead to more pronounced increase in winter evapotranspiration over the same areas. The simulated 12-months Standardized Runoff Index (SRI) clearly shows severe persistent hydrological droughts

  18. Subduction zone guided waves in Northern Chile

    NASA Astrophysics Data System (ADS)

    Garth, Thomas; Rietbrock, Andreas

    2016-04-01

    Guided wave dispersion is observed in subduction zones as high frequency energy is retained and delayed by low velocity structure in the subducting slab, while lower frequency energy is able to travel at the faster velocities associated with the surrounding mantle material. As subduction zone guided waves spend longer interacting with the low velocity structure of the slab than any other seismic phase, they have a unique capability to resolve these low velocity structures. In Northern Chile, guided wave arrivals are clearly observed on two stations in the Chilean fore-arc on permanent stations of the IPOC network. High frequency (> 5 Hz) P-wave arrivals are delayed by approximately 2 seconds compared to the low frequency (< 2 Hz) P-wave arrivals. Full waveform finite difference modelling is used to test the low velocity slab structure that cause this P-wave dispersion. The synthetic waveforms produced by these models are compared to the recorded waveforms. Spectrograms are used to compare the relative arrival times of different frequencies, while the velocity spectra is used to constrain the relative amplitude of the arrivals. Constraining the waveform in these two ways means that the full waveform is also matched, and the low pass filtered observed and synthetic waveforms can be compared. A combined misfit between synthetic and observed waveforms is then calculated following Garth & Rietbrock (2014). Based on this misfit criterion we constrain the velocity model by using a grid search approach. Modelling the guided wave arrivals suggest that the observed dispersion cannot be solely accounted for by a single low velocity layer as suggested by previous guided wave studies. Including dipping low velocity normal fault structures in the synthetic model not only accounts for the observed strong P-wave coda, but also produces a clear first motion dispersion. We therefore propose that the lithospheric mantle of the subducting Nazca plate is highly hydrated at intermediate

  19. The Effect of Riparian Zones in Structuring Small Mammal Communities in the Southern Appalachians

    Treesearch

    Joshua Laerm; Michael A. Menzel; Dorothy J. Wolf; James R. Welch

    1997-01-01

    Riparian zones have been shown to be important in structuring vertebrate communities and in maintaining biodiversity. We examined the role of riparian zones in structuring small mammal communities in a southern Appalachian watershed at Coweeta Hydrological Laboratory, Macon County, North Carolina. We established pitfall and live-trap grids in three replicates each of...

  20. Expedition Atacama - project AMOS in Chile

    NASA Astrophysics Data System (ADS)

    Tóth, J.; Kaniansky, S.

    2016-01-01

    The Slovak Video Meteor Network operates since 2009 (Tóth et al., 2011). It currently consists of four semi-automated all-sky video cameras, developed at the Astronomical Observatory in Modra, Comenius University in Bratislava, Slovakia. Two new generations of AMOS (All-sky Meteor Orbit System) cameras operate fully automatically at the Canary Islands, Tenerife and La Palma, since March 2015 (Tóth et al., 2015). As a logical step, we plan to cover the southern hemisphere from Chile. We present observational experiences in meteor astronomy from the Atacama Desert and other astronomical sites in Chile. This summary of the observations lists meteor spectra records (26) between Nov.5-13, 2015 mostly Taurid meteors, single and double station meteors as well as the first light from the permanent AMOS stations in Chile.

  1. Paleoseismology of the Southern Section of the Black Mountains and Southern Death Valley Fault Zones, Death Valley, United States

    USGS Publications Warehouse

    Sohn, Marsha S.; Knott, Jeffrey R.; Mahan, Shannon

    2014-01-01

    The Death Valley Fault System (DVFS) is part of the southern Walker Lane–eastern California shear zone. The normal Black Mountains Fault Zone (BMFZ) and the right-lateral Southern Death Valley Fault Zone (SDVFZ) are two components of the DVFS. Estimates of late Pleistocene-Holocene slip rates and recurrence intervals for these two fault zones are uncertain owing to poor relative age control. The BMFZ southernmost section (Section 1W) steps basinward and preserves multiple scarps in the Quaternary alluvial fans. We present optically stimulated luminescence (OSL) dates ranging from 27 to 4 ka of fluvial and eolian sand lenses interbedded with alluvial-fan deposits offset by the BMFZ. By cross-cutting relations, we infer that there were three separate ground-rupturing earthquakes on BMFZ Section 1W with vertical displacement between 5.5 m and 2.75 m. The slip-rate estimate is ∼0.2 to 1.8 mm/yr, with an earthquake recurrence interval of 4,500 to 2,000 years. Slip-per-event measurements indicate Mw 7.0 to 7.2 earthquakes. The 27–4-ka OSL-dated alluvial fans also overlie the putative Cinder Hill tephra layer. Cinder Hill is offset ∼213 m by SDVFZ, which yields a tentative slip rate of 1 to 8 mm/yr for the SDVFZ.

  2. Crustal architecture and tectonic evolution of the Cauvery Suture Zone, southern India

    NASA Astrophysics Data System (ADS)

    Chetty, T. R. K.; Yellappa, T.; Santosh, M.

    2016-11-01

    The Cauvery suture zone (CSZ) in southern India has witnessed multiple deformations associated with multiple subduction-collision history, with incorporation of the related accretionary belts sequentially into the southern continental margin of the Archaean Dharwar craton since Neoarchean to Neoproterozoic. The accreted tectonic elements include suprasubduction complexes of arc magmatic sequences, high-grade supracrustals, thrust duplexes, ophiolites, and younger intrusions that are dispersed along the suture. The intra-oceanic Neoarchean-Neoproterozoic arc assemblages are well exposed in the form of tectonic mélanges dominantly towards the eastern sector of the CSZ and are typically subjected to complex and multiple deformation events. Multi-scale analysis of structural elements with detailed geological mapping of the sub-regions and their structural cross sections, geochemical and geochronological data and integrated geophysical observations suggest that the CSZ is an important zone that preserves the imprints of multiple cycles of Precambrian plate tectonic regimes.

  3. 76 FR 34859 - Safety Zone; Augusta Southern Nationals Drag Boat Race, Savannah River, Augusta, GA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-15

    ...-AA00 Safety Zone; Augusta Southern Nationals Drag Boat Race, Savannah River, Augusta, GA AGENCY: Coast... Boat Race. The Augusta Southern Nationals Drag Boat Race will consist of a series of high-speed boat... hazards associated with the high-speed boat races. Discussion of Rule From July 14, 2011 through July 17...

  4. Investigation of Along-Arc Geochemical Variations in the Southern Volcanic Zone: Azufre-Planchon-Peteroa Volcanic Complex, Southern Chile

    NASA Astrophysics Data System (ADS)

    Holbik, S. P.; Hickey-Vargas, R.; Tormey, D.

    2012-12-01

    The Andean Southern Volcanic Zone (SVZ) is a vast and complex continental arc that has been studied extensively to provide an understanding of arc-magma genesis, the origin and chemical evolution of the continental crust, and geochemical compositions of volcanic products. This study focuses on volcanic rocks from the Azufre-Planchon-Peteroa (APP 35°15'S) volcanic complex, within the Transitional SVZ (34.3-37.0 °S), where crustal thickness increases from approximately 30 km in the south (Central SVZ), to 55 km in the north (Northern SVZ). Planchon is the northernmost volcano in the SVZ to erupt basaltic products, while Peteroa is the currently active cone, erupting tephra of andesitic composition, most recently in September of 2011. New data for the APP are consistent with the hypothesis of Tormey et al. (1995) that the APP experienced variable depths of crystal fractionation, and that crustal assimilation at Planchon is restricted to the lower crustal depths, as reflected by limited variability in 87Sr/86Sr isotopes. New δ18O data (26.5‰) from an outcropping dolomitic limestone country rock in the vicinity of the Azufre volcano also confirms the upper crustal source of anomalously high (7.1 and 7.3‰) oxygen isotopic values for Azufre dacites. A trend of high La/Yb (6.5-9.1) and Yb depletion with increasing La/Yb for Planchon basalts is consistent with the role of garnet as a residual or crystallizing phase at lower crustal depths, however, the La/Yb range is small when compared to published data from nearby TSVZ centers such as Nevado de Longavi (La/Yb = 5.5 to 16.7) and San Pedro Pellado (La/Yb =7.2 to 13.6). Geochemical modeling of the Planchon data shows that both hornblende and garnet must be involved in the magmatic evolution, even though erupted basalts are free of major hydrous phases, in order to account for the more limited range of La/Yb. Interestingly, baseline values of La/Yb for basalt and basaltic andesites from throughout the TSVZ, including

  5. Seismic attenuation structure beneath Nazca Plate subduction zone in southern Peru

    NASA Astrophysics Data System (ADS)

    Jang, H.; Kim, Y.; Clayton, R. W.

    2017-12-01

    We estimate seismic attenuation in terms of quality factors, QP and QS using P and S phases, respectively, beneath Nazca Plate subduction zone between 10°S and 18.5°S latitude in southern Peru. We first relocate 298 earthquakes with magnitude ranges of 4.0-6.5 and depth ranges of 20-280 km. We measure t*, which is an integrated attenuation through the seismic raypath between the regional earthquakes and stations. The measured t* are inverted to construct three-dimensional attenuation structures of southern Peru. Checkerboard test results for both QP and QS structures ensure good resolution in the slab-dip transition zone between flat and normal slab subduction down to a depth of 200 km. Both QP and QS results show higher attenuation continued down to a depth of 50 km beneath volcanic arc and also beneath the Quimsachata volcano, the northernmost young volcano, located far east of the main volcanic front. We also observe high attenuation in mantle wedge especially beneath the normal subduction region in both QP and QS (100-130 in QP and 100-125 in QS) and slightly higher QP and QS beneath the flat-subduction and slab-dip transition regions. We plan to relate measured attenuation in the mantle wedge to material properties such as viscosity to understand the subduction zone dynamics.

  6. Crustal seismicity in central Chile

    NASA Astrophysics Data System (ADS)

    Barrientos, S.; Vera, E.; Alvarado, P.; Monfret, T.

    2004-06-01

    Both the genesis and rates of activity of shallow intraplate seismic activity in central Chile are poorly understood, mainly because of the lack of association of seismicity with recognizable fault features at the surface and a poor record of seismic activity. The goal of this work is to detail the characteristics of seismicity that takes place in the western flank of the Andes in central Chile. This region, located less than 100 km from Santiago, has been the site of earthquakes with magnitudes up to 6.9, including several 5+ magnitude shocks in recent years. Because most of the events lie outside the Central Chile Seismic Network, at distances up to 60 km to the east, it is essential to have adequate knowledge of the velocity structure in the Andean region to produce the highest possible quality of epicentral locations. For this, a N-S refraction line, using mining blasts of the Disputada de Las Condes open pit mine, has been acquired. These blasts were detected and recorded as far as 180 km south of the mine. Interpretation of the travel times indicates an upper crustal model consisting of three layers: 2.2-, 6.7-, and 6.1-km thick, overlying a half space; their associated P wave velocities are 4.75-5.0 (gradient), 5.8-6.0 (gradient), 6.2, and 6.6 km/s, respectively. Hypocentral relocation of earthquakes in 1986-2001, using the newly developed velocity model, reveals several regions of concentrated seismicity. One clearly delineates the fault zone and extensions of the strike-slip earthquake that took place in September 1987 at the source of the Cachapoal River. Other regions of activity are near the San José volcano, the source of the Maipo River, and two previously recognized lineaments that correspond to the southern extension of the Pocuro fault and Olivares River. A temporary array of seismographs, installed in the high Maipo River (1996) and San José volcano (1997) regions, established the hypocentral location of events with errors of less than 1 km

  7. Structure and Deformation in the Transpressive Zone of Southern California Inferred from Seismicity, Velocity, and Qp Models

    NASA Astrophysics Data System (ADS)

    Hauksson, E.; Shearer, P.

    2004-12-01

    We synthesize relocated regional seismicity and 3D velocity and Qp models to infer structure and deformation in the transpressive zone of southern California. These models provide a comprehensive synthesis of the tectonic fabric of the upper to middle crust, and the brittle ductile transition zone that in some cases extends into the lower crust. The regional seismicity patterns in southern California are brought into focus when the hypocenters are relocated using the double difference method. In detail, often the spatial correlation between background seismicity and late Quaternary faults is improved as the hypocenters become more clustered, and the spatial patterns are more sharply defined. Along some of the strike-slip faults the seismicity clusters decrease in width and form alignments implying that in many cases the clusters are associated with a single fault. In contrast, the Los Angeles Basin seismicity remains mostly scattered, reflecting a 3D distribution of the tectonic compression. We present the results of relocating 327,000 southern California earthquakes that occurred between 1984 and 2002. In particular, the depth distribution is improved and less affected by layer boundaries in velocity models or other similar artifacts, and thus improves the definition of the brittle ductile transition zone. The 3D VP and VP/VS models confirm existing tectonic interpretations and provide new insights into the configuration of the geological structures in southern California. The models extend from the US-Mexico border in the south to the Coast Ranges and Sierra Nevada in the north, and have 15 km horizontal grid spacing and an average vertical grid spacing of 4 km, down to 22 km depth. The heterogeneity of the crustal structure as imaged in both the VP and VP/VS models is larger within the Pacific than the North America plate, reflecting regional asymmetric variations in the crustal composition and past tectonic processes. Similarly, the relocated seismicity is

  8. Definition of sanitary boundaries to prevent ISAv spread between salmon farms in southern Chile based on numerical simulations of currents

    NASA Astrophysics Data System (ADS)

    Olivares, Gonzalo; Sepúlveda, H. H.; Yannicelli, B.

    2015-06-01

    The infectious Salmon Anemia virus (ISAv) is a pathogen that mainly affects the Atlantic Salmon (Salmo salar). It was detected in Norway in 1984 and in June 2007 appeared in Chile, producing a drop of more than 30% in the country's production level. It is expected that with certain regularity, outbreaks will continue to appear in Chile without the need of reintroducing the virus from foreign countries. We present a numerical study of the influence of winds and tides in the dispersion of lagrangian particles to simulate the transport of ISAv in the Aysen region, in southern Chile. This study combines the use of numerical models of the ocean and atmosphere, lagrangian tracking and biological aspects of ISAv infections. As in previous results, a wider dispersion of ISAv was observed during spring tides. Temporal changes in wind significantly modified the transport of viral particles from an infected center. Under similar forcing conditions, the areas of risk associated to culture sites separated by a few kilometers could be very different. Our main results remark the importance of the use of a detailed knowledge of hydrographic and atmospheric circulation in the definition of boundaries for sanitary management areas. We suggest that a methodology similar to the one presented in this study should be considered to define sanitary strategies to minimize the occurrence of native outbreaks of ISAv.

  9. The Southern Part of the Southern Volcanic Zone (SSVZ; 42-46S) of the Andes: History of Medium and Large Explosive Holocene Eruptions

    NASA Astrophysics Data System (ADS)

    Stern, C. R.; Naranjo, J. A.

    2008-12-01

    Chaitén volcano is one of 13 large volcanic centers, and numerous small cones, comprising the southern part of the Andean Southern Volcanic Zone (SVZ), that results from the subduction of the Nazca plate (at 7.8 cm/yr) between the landward extension of the Chiloé FZ at 42S and the Chile Rise - Trench triple junction at 46S. Chaitén is a rhyolite dome inside a 3 km diameter caldera located 15 km west of the larger Michinmahuida stratovolcano. Other stratovolcanoes in the SSVZ include Yate, Hornopirén, Corcovado, Yanteles, Melimoyu, Mentolat, Cay and Macá. Hudson volcano, the southernmost in the Southern SVZ, is a large 10 km caldera, while Huequi and Hualaihué - Cordón Cabrera are a group of small aligned cinder cones possibly related to a larger eroded volcanic complex. Prior to the May 2008 eruption of Chaitén, the only well documented historic eruptions in this segment of the Andean arc were the explosive eruption of Hudson in August 1991 (Naranjo et al. 1993), and two eruptions of Michinmahuida in 1742 and 1834-35. Tephra deposits provide evidence of 11 prehistoric explosive Holocene eruptions of the southernmost SSVZ Hudson volcano, including two large eruptions near <6700 and <3600 BP (Naranjo and Stern 1998). The 6700 BP eruption produced greater than 18 km3 of andesitic tephra, possibly the largest Holocene eruption in all the southern Andes. Although Hudson is clearly the most active of the Southern SVZ volcanoes in terms of both volume and frequency of explosive eruptions, tephra deposits indicate that seven of the other SSVZ volcanoes, including Chaitén, also have had medium to large Holocene explosive eruptions (Naranjo and Stern 2004). Three of these eruptions were from Corcovado at approximately <9190, <7980 and <6870 BP, one from Yanteles at <9180 BP, two from Melimoyu at <2740 and <1750 BP, one from Mentolat at <6960 and one from Macá at <1540 BP. Two other eruptions, at <6350 and <3820 BP, we interpret as having been produced by

  10. Imprint of Southern Red Sea Major Tectonic Zone In A New Bouguer Anomaly Map of Southern Yemen Margin

    NASA Astrophysics Data System (ADS)

    Blecha, V.

    A new Bouguer anomaly map of western part of southern Yemen margin has been compiled. Densities of rock samples from main geological units (Precambrian base- ment, Mesozoic sediments, Tertiary volcanites) have been measured and used for grav- ity modeling. Regional gravity map indicates decrease of thickness of continental crust from volcanites of the Yemen Trap Series towards the coast of the Gulf of Aden. Most remarkable feature in the map of residual anomalies is a positive anomaly over the Dhala graben. The Dhala graben is a prominent geological structure in the area of study trending parallel to the Red Sea axis. Gravity modeling on a profile across the Dhala graben presumes intrusive plutonic rocks beneath the graben. There are two other areas in the southwestern tip of Arabia, which have essentially the same struc- tural position as the Dhala graben: the Jabal Tirf volcanic rift zone in the southern Saudi Arabia and Jabal Hufash extensional zone in northern Yemen. All three areas extend along the line trending parallel to the Red Sea axis with length of about 500 km. The line coincides with the axis of Afar (Danakil) depression after Arabia is shifted and rotated back to Africa. These facts imply conclusion that the Oligocene - Early Miocene magmatic activity on the Jabal Tirf - Dhala lineament is related to the same original deep tectonic zone, forming present-day Afar depression and still active.

  11. International Summer School on Astronomy and Space Science in Chile, first experience.

    NASA Astrophysics Data System (ADS)

    Stepanova, M.; Arellano-Baeza, A. A.

    I International Summer School on Astronomy and Space Science took place in the Elqui Valley Chile January 15-29 2005 Eighty 12-17 year old students from Chile Russia Venezuela and Bulgaria obtained a valuable experience to work together with outstanding scientists from Chile and Russia and with Russian cosmonaut Alexander Balandine They also had opportunity to visit the main astronomical observatories and to participate in workshops dedicated to the telescope and satellite design and remote sensing This activity was supported by numerous institutions in Chile including the Ministry of Education the European Southern Observatory Chilean Space Agency Chilean Air Force Latin American Association of Space Geophysics the principal Chilean universities and the First Lady Mrs Luisa Duran

  12. Stilbene levels in grape cane of different cultivars in southern Chile: determination by HPLC-DAD-MS/MS method.

    PubMed

    Vergara, Carola; von Baer, Dietrich; Mardones, Claudia; Wilkens, Andrea; Wernekinck, Katerina; Damm, Anika; Macke, Sebastian; Gorena, Tamara; Winterhalter, Peter

    2012-02-01

    Health benefits of trans-resveratrol and other stilbenes in grapes, must, and wine have been pointed out by numerous authors. Less attention has been paid to the presence of stilbene derivatives in viticultural residues, such as grape canes. The present work reports the first results of a systematic study of stilbene levels in different grape varieties and cultivation areas in Chile, to evaluate their potential as an alternative source of bioactive stilbenes. In all cane samples, the predominant stilbene is trans-resveratrol, followed by ε-viniferin and piceatannol. In canes of Pinot noir up to 5590 ± 172 mg kg(-1) of trans-resveratrol and up to 6915 ± 175 mg kg(-1) of total stilbenes were detected. The observed concentrations of stilbenes in canes of Pinot noir from southern Chile until now are higher than those reported previously for this red variety. However, the highest concentration of total stilbenes observed in the analyzed samples was in the canes of white variety Gewürztraminer with 7857 ± 498 mg kg(-1). Preliminary results indicate that these levels can evolve if canes are left for some months on the vineyard after pruning, observing an increase during the first 2 months and a decrease after this period.

  13. Serological Evidence of Hantavirus Infection in Apparently Healthy People from Rural and Slum Communities in Southern Chile

    PubMed Central

    Muñoz-Zanzi, Claudia; Saavedra, Farides; Otth, Carola; Domancich, Ljubica; Hott, Melissa; Padula, Paula

    2015-01-01

    Hantavirus disease in America has been recognizable because of its rapid progression in clinical cases, occurrence in previously healthy young adults, and high case fatality rate. Hantavirus disease has been proposed now to define the diversity of clinical manifestations. Since 1995, a total of 902 cases of hantavirus pulmonary syndrome have been reported in Chile, caused by Andes virus (ANDV), with overall fatality of 32%. This report describes the sero-epidemiology of hantavirus in apparently healthy people in rural and urban slum communities from southern Chile. Ten of 934 samples yielded a positive result resulting in a seroprevalence of 1.07% (95% confidence intervals: 0.05%–2.0%). A higher proportion of positive samples was found among individuals from rural villages (1.3%) and slums (1.5%) compared with farms (0.5%). Seropositivity was associated with age (p = 0.011), low education level (p = 0.006) and occupations linked to the household (homemaker, retired, or student) (p = 0.016). No evidence of infection was found in 38 sigmodontinae rodents trapped in the peri-domestic environment. Our findings highlight that exposure risk was associated with less documented risk factors, such as women in slum and rural villages, and the occurrence of infection that may have presented as flu-like illness that did not require medical attention or was misdiagnosed. PMID:25912713

  14. Possible detachment zone in Precambrian rocks of Kanjamalai Hills, Cauvery Suture Zone, Southern India: Implications to accretionary tectonics

    NASA Astrophysics Data System (ADS)

    Mohanty, D. P.; Chetty, T. R. K.

    2014-07-01

    Existence of a possible detachment zone at Elampillai region, NW margin of Kanjamalai Hills, located in the northern part of Cauvery Suture Zone (CSZ), Southern India, is reported here for the first time. Detailed structural mapping provides anatomy of the zone, which are rarely preserved in Precambrian high grade terranes. The detachment surface separates two distinct rock units of contrasting lithological and structural characters: the upper and lower units. The detachment zone is characterized by a variety of fold styles with the predominance of tight isoclinal folds with varied plunge directions, limb rotations and the hinge line variations often leading to lift-off fold like geometries and deformed sheath folds. Presence of parasitic folding and associated penetrative strains seem to be controlled by differences in mechanical stratigraphy, relative thicknesses of the competent and incompetent units, and the structural relief of the underlying basement. Our present study in conjunction with other available geological, geochemical and geochronological data from the region indicates that the structures of the detachment zone are genetically related to thrust tectonics forming a part of subduction-accretion-collision tectonic history of the Neoproterozoic Gondwana suture.

  15. Subduction zone mantle enrichment by fluids and Zr-Hf-depleted crustal melts as indicated by backarc basalts of the Southern Volcanic Zone, Argentina

    NASA Astrophysics Data System (ADS)

    Holm, Paul M.; Søager, Nina; Alfastsen, Mads; Bertotto, Gustavo W.

    2016-10-01

    We aim to identify the components metasomatizing the mantle above the subducting Nazca plate under part of the Andean Southern Volcanic Zone (SVZ). We present new major and ICP-MS trace element and Sr, Nd and high-precision Pb isotope analyses of primitive olivine-phyric alkali basalts from the Northern Segment Volcanic Field, part of the Payenia province in the backarc of the Transitional SVZ. One new 40Ar-39Ar age determination confirms the Late Pleistocene age of this most northerly part of the province. All analysed rocks have typical subduction zone type incompatible element enrichment, and the rocks of the Northern Segment, together with the neighbouring Nevado Volcanic Field, have isotopic compositions intermediate between adjacent Transitional SVZ arc rocks and southern Payenia OIB-type basaltic rocks. Modelling the Ba-Th-Sm variation we demonstrate that fluids as well as 1-2% melts of upper continental crust (UCC) enriched their mantle sources, and La-Nb-Sm variations additionally indicate that the pre-metasomatic sources ranged from strongly depleted to undepleted mantle. Low Eu/Eu* and Sr/Nd also show evidence for a UCC component in the source. The contribution of Chile Trench sediments to the magmas seems insignificant. The Zr/Sm and Hf/Sm ratios are relatively low in many of the Northern Segment rocks, ranging down to 17 and 0.45, respectively, which, together with relatively high Th/U, is argued to indicate that the metasomatizing crustal melts were derived by partial melting of subducted UCC that had residual zircon, in contrast to the UCC melts added to Transitional SVZ arc magmas. Mixing between depleted and undepleted mantle, enriched by UCC and fluids, is suggested by Sr, Nd and Pb isotopes of the Northern Segment and Nevado magmas. The metasomatized undepleted mantle south of the Northern Segment is suggested to be part of upwelling OIB-type mantle, whereas the pre-metasomatically depleted mantle also can be found as a component in some arc

  16. Economic effect of bovine abortion syndrome in commercial dairy herds in Southern Chile.

    PubMed

    Gädicke, P; Vidal, R; Monti, G

    2010-10-01

    Bovine abortion is a limiting factor for dairy business, as it decreases milk production and the potential, number of herd replacements, increases feeding and medical treatment costs, increases the number of artificial inseminations to obtain a calf as well as culling rates of cows. An estimation of the economic impact of abortion in dairy farms in Chile is not available yet. The aim of this study was to estimate the economic consequences of bovine abortion syndrome (BAS) in dairy cows from Chile. A stochastic model was proposed to evaluate the cost of an abortion on a yearly basis to include variability in cost and income by dairy and by year. The marginal total net revenue (ΔTNR) for a typical, lactation was obtained by the calculating the difference between total revenues (retail milk and calf sales) and total expenses (production cost (cows, feeding, labor, health) plus administrative and, general costs) for lactation with and without abortion. Production data were obtained from a retrospective study of 127 dairy herds located in southern Chile between 2000 and 2006. Milk production from cows with and without abortion was estimated by a mixed model using milk test day data. Production cost and prices paid to farmers were obtained from service company records (TODOAGRO S.A.). Cost and income value was corrected for inflation and expressed in the values from 2006. In addition, a separate analysis for different parities (1, 2, 3 or more) was performed. Distributions for the stochastic variables were obtained by fitting distributions from our database using @Risk. The stochastic variables included in the analysis were all related to income, feeding, depreciation, health, Artificial Insemination and general costs like fuel, salaries, taxes, etc. There was a high probability (89.20%) of a negative ΔTNR in lactations with abortion for overall, parities, with a mean loss of $ -143.32. Stratifying by parity, the predicted mean of the distribution for ΔTNR in each

  17. The mafic-ultramafic complex of Aniyapuram, Cauvery Suture Zone, southern India: Petrological and geochemical constraints for Neoarchean suprasubduction zone tectonics

    NASA Astrophysics Data System (ADS)

    Yellappa, T.; Venkatasivappa, V.; Koizumi, T.; Chetty, T. R. K.; Santosh, M.; Tsunogae, T.

    2014-12-01

    Several Precambrian mafic-ultramafic complexes occur along the Cauvery Suture Zone (CSZ) in Southern Granulite Terrain, India. Their origin, magmatic evolution and relationship with the associated high-grade rocks have not been resolved. The Aniyapuram Mafic-Ultramafic Complex (AMUC), the focus of the present study in southern part of the CSZ, is dominantly composed of peridotites, pyroxenites, gabbros, metagabbros/mafic granulites, hornblendites, amphibolites, plagiogranites, felsic granulites and ferruginous cherts. The rock types in the AMUC are structurally emplaced within hornblende gneiss (TTG) basement rocks and are highly deformed. The geochemical signature of the amphibolites indicates tholeiitic affinity for the protolith with magma generation in island arc-setting. N-MORB normalized pattern of the amphibolites show depletion in HFS-elements (P, Zr, Sm, Ti, and Y) and enrichment of LIL-elements (Rb, Ba, Th, Sr) with negative Nb anomalies suggesting involvement of subduction component in the depleted mantle source and formation in a supra-subduction zone tectonic setting. Our new results when correlated with the available age data suggest that the lithological association of AMUC represent the remnants of the Neoarchean oceanic lithosphere.

  18. Low Velocity Zones along the San Jacinto Fault, Southern California, inferred from Local Earthquakes

    NASA Astrophysics Data System (ADS)

    Li, Z.; Yang, H.; Peng, Z.; Ben-Zion, Y.; Vernon, F.

    2013-12-01

    Natural fault zones have regions of brittle damage leading to a low-velocity zone (LVZ) in the immediate vicinity of the main fault interface. The LVZ may amplify ground motion, modify rupture propagation, and impact derivation of earthquke properties. Here we image low-velocity fault zone structures along the San Jacinto Fault (SJF), southern California, using waveforms of local earthquakes that are recorded at several dense arrays across the SJFZ. We use generalized ray theory to compute synthetic travel times to track the direct and FZ-reflected waves bouncing from the FZ boundaries. This method can effectively reduce the trade-off between FZ width and velocity reduction relative to the host rock. Our preliminary results from travel time modeling show the clear signature of LVZs along the SJF, including the segment of the Anza seismic gap. At the southern part near the trifrication area, the LVZ of the Clark Valley branch (array JF) has a width of ~200 m with ~55% reduction in Vp and Vs. This is consistent with what have been suggested from previous studies. In comparison, we find that the velocity reduction relative to the host rock across the Anza seismic gap (array RA) is ~50% for both Vp and Vs, nearly as prominent as that on the southern branches. The width of the LVZ is ~230 m. In addition, the LVZ across the Anza gap appears to locate in the northeast side of the RA array, implying potential preferred propagation direction of past ruptures.

  19. Aerosols Observations with a new lidar station in Punta Arenas, Chile

    NASA Astrophysics Data System (ADS)

    Barja, Boris; Zamorano, Felix; Ristori, Pablo; Otero, Lidia; Quel, Eduardo; Sugimoto, Nobuo; Shimizu, Atsushi; Santana, Jorge

    2018-04-01

    A tropospheric lidar system was installed in Punta Arenas, Chile (53.13°S, 70.88°W) in September 2016 under the collaboration project SAVERNET (Chile, Japan and Argentina) to monitor the atmosphere. Statistical analyses of the clouds and aerosols behavior and some cases of dust detected with lidar, at these high southern latitude and cold environment regions during three months (austral spring) are discussed using information from satellite, modelling and solar radiation ground measurements.

  20. Formation of albitite-hosted uranium within IOCG systems: the Southern Breccia, Great Bear magmatic zone, Northwest Territories, Canada

    NASA Astrophysics Data System (ADS)

    Montreuil, Jean-François; Corriveau, Louise; Potter, Eric G.

    2015-03-01

    Uranium and polymetallic U mineralization hosted within brecciated albitites occurs one kilometer south of the magnetite-rich Au-Co-Bi-Cu NICO deposit in the southern Great Bear magmatic zone (GBMZ), Canada. Concentrations up to 1 wt% U are distributed throughout a 3 by 0.5 km albitization corridor defined as the Southern Breccia zone. Two distinct U mineralization events are observed. Primary uraninite precipitated with or without pyrite-chalcopyrite ± molybdenite within magnetite-ilmenite-biotite-K-feldspar-altered breccias during high-temperature potassic-iron alteration. Subsequently, pitchblende precipitated in earthy hematite-specular hematite-chlorite veins associated with a low-temperature iron-magnesium alteration. The uraninite-bearing mineralization postdates sodic (albite) and more localized high-temperature potassic-iron (biotite-magnetite ± K-feldspar) alteration yet predates potassic (K-feldspar), boron (tourmaline) and potassic-iron-magnesium (hematite ± K-feldspar ± chlorite) alteration. The Southern Breccia zone shares attributes of the Valhalla (Australia) and Lagoa Real (Brazil) albitite-hosted U deposits but contains greater iron oxide contents and lower contents of riebeckite and carbonates. Potassium, Ni, and Th are also enriched whereas Zr and Sr are depleted with respect to the aforementioned albitite-hosted U deposits. Field relationships, geochemical signatures and available U-Pb dates on pre-, syn- and post-mineralization intrusions place the development of the Southern Breccia and the NICO deposit as part of a single iron oxide alkali-altered (IOAA) system. In addition, this case example illustrates that albitite-hosted U deposits can form in albitization zones that predate base and precious metal ore zones in a single IOAA system and become traps for U and multiple metals once the tectonic regime favors fluid mixing and oxidation-reduction reactions.

  1. A cross sectional observational study to estimate herd level risk factors for Leptospira spp. serovars in small holder dairy cattle farms in southern Chile

    PubMed Central

    2014-01-01

    Background The south of Chile constitutes the main cattle milk producing area of the country. Regarding leptospirosis control in Chile, there is neither an official program nor an epidemiological characterization of smallholder dairy farms. This study was carried out to determine Leptospira seroprevalence and to evaluate risk factors associated with seropositivity at herd level in smallholder bovine dairy herds in southern Chile. A cross-sectional study was conducted, and a convenient sample of 1,537 apparently healthy dairy cows was included in the study. Individual blood samples were taken and examined for six selected reference Leptospira serovars by the Microscopic Agglutination Test (MAT). Results Of the included herds 75% (52/69) showed serological titers against one or more Leptospira serovar. Leptospira borgpetersenii serovar Hardjo was the serovar most frequently (81%) reported from animals with positive results. The variables considered risk factors for Leptospira seropositivity were calve natural breeding system, using a specific calving area and vaccination against Leptospira. Adult cows in contact with calves weaned, proved to be a protective factor against infection. Conclusions Herds neglecting the management practices mentioned in this study could represent an important source of Leptospira infection for other herds in the same geographic area, as well as for other animal species. PMID:24906684

  2. A cross sectional observational study to estimate herd level risk factors for Leptospira spp. serovars in small holder dairy cattle farms in southern Chile.

    PubMed

    Salgado, Miguel; Otto, Barbara; Sandoval, Errol; Reinhardt, German; Boqvist, Sofia

    2014-06-06

    The south of Chile constitutes the main cattle milk producing area of the country. Regarding leptospirosis control in Chile, there is neither an official program nor an epidemiological characterization of smallholder dairy farms. This study was carried out to determine Leptospira seroprevalence and to evaluate risk factors associated with seropositivity at herd level in smallholder bovine dairy herds in southern Chile.A cross-sectional study was conducted, and a convenient sample of 1,537 apparently healthy dairy cows was included in the study. Individual blood samples were taken and examined for six selected reference Leptospira serovars by the Microscopic Agglutination Test (MAT). Of the included herds 75% (52/69) showed serological titers against one or more Leptospira serovar. Leptospira borgpetersenii serovar Hardjo was the serovar most frequently (81%) reported from animals with positive results. The variables considered risk factors for Leptospira seropositivity were calve natural breeding system, using a specific calving area and vaccination against Leptospira. Adult cows in contact with calves weaned, proved to be a protective factor against infection. Herds neglecting the management practices mentioned in this study could represent an important source of Leptospira infection for other herds in the same geographic area, as well as for other animal species.

  3. Snow cover correlation between Mt. Villarrica and Mt. Lliama in Chile

    NASA Astrophysics Data System (ADS)

    Kim, Jeong-Cheol; Park, Sung-Hwan; Jung, Hyung-Sup

    2014-11-01

    The Southern Volcanic Zone (SVZ) of Chile consists of many volcanoes, and all of the volcanoes are covered with snow at the top of mountain. Monitoring snow cover variations in these regions can give us a key parameter in order to understand the mechanisms of volcanic activity. In this study, we investigate on the volcanic activity and snow cover interaction from snow cover area mapping, snow-line extraction. The study areas cover Mt. Villarrica and Mt. Llaima, Chile. Both of them are most active volcanos in SVZ. Sixty Landsat TM and Landsat ETM+ images are used for observing snow cover variations of Mt. Villarrica and Mt. Llaima, spanning the 25 years from September 1986 to February 2011. Results show that snow cover area between volcanic activity and non-activity are largely changed from 42.84 km2 to 13.41 km2, temporarily decreased 79% at the Mt. Villarrica and from 28.98 km2 to 3.82 km2, temporarily decreased 87% at the Mt. Villarrica. The snow line elevation of snow cover retreated by approximately 260 m from 1,606m to 1,871 m at the Mt. Villarrica, approximately 266m from 1,741m to 2,007m at the Mt. Llaima. The results show that there are definitely correlations between snow cover and volcanic activity.

  4. The Bulimulidae (Mollusca: Pulmonata) from the Región de Atacama, northern Chile

    PubMed Central

    2015-01-01

    The bulimulid genus Bostryx Troschel, 1847 is the most species-rich genus of land snails found in Chile, with the majority of its species found only in the northern part of the country, usually in arid coastal zones. This genus has been sparsely studied in Chile and there is little information on their distribution, diversity or ecology. Here, for the first time, a formal analysis of the diversity of bulimulids in the Región de Atacama, northern Chile, is reported. Of the seventeen species recorded for the area, most of them were efectively found in the field collections and one record was based on literature. Five taxa are described as new: Bostryx ancavilorum sp. nov., Bostryx breurei sp. nov., Bostryx calderaensis sp. nov., Bostryx ireneae sp. nov. and Bostryx valdovinosi sp. nov., and the known geographic distribution of seven species is extended. Results reveal that the Región de Atacama is the richest region in terrestrial snails in Chile, after the Juan Fernández Archipelago. All of the terrestrial molluscan species occurring in the area are endemic to Chile, most of them with restricted geographic distributions along the coastal zones, and none of them are currently protected by law. Further sampling in northern Chile will probably reveal more snail species to be discovered and described. PMID:26587346

  5. The Bulimulidae (Mollusca: Pulmonata) from the Región de Atacama, northern Chile.

    PubMed

    Araya, Juan Francisco

    2015-01-01

    The bulimulid genus Bostryx Troschel, 1847 is the most species-rich genus of land snails found in Chile, with the majority of its species found only in the northern part of the country, usually in arid coastal zones. This genus has been sparsely studied in Chile and there is little information on their distribution, diversity or ecology. Here, for the first time, a formal analysis of the diversity of bulimulids in the Región de Atacama, northern Chile, is reported. Of the seventeen species recorded for the area, most of them were efectively found in the field collections and one record was based on literature. Five taxa are described as new: Bostryx ancavilorum sp. nov., Bostryx breurei sp. nov., Bostryx calderaensis sp. nov., Bostryx ireneae sp. nov. and Bostryx valdovinosi sp. nov., and the known geographic distribution of seven species is extended. Results reveal that the Región de Atacama is the richest region in terrestrial snails in Chile, after the Juan Fernández Archipelago. All of the terrestrial molluscan species occurring in the area are endemic to Chile, most of them with restricted geographic distributions along the coastal zones, and none of them are currently protected by law. Further sampling in northern Chile will probably reveal more snail species to be discovered and described.

  6. Recovery of black-necked swans, macrophytes and water quality in a Ramsar wetland of southern Chile: Assessing resilience following sudden anthropogenic disturbances.

    PubMed

    Jaramillo, Eduardo; Lagos, Nelson A; Labra, Fabio A; Paredes, Enrique; Acuña, Emilio; Melnick, Daniel; Manzano, Mario; Velásquez, Carlos; Duarte, Cristian

    2018-07-01

    In 2004 migration and mortality for unknown reasons of the herbivorous Black necked swan (Cygnus melancorhyphus (Molina, 1782)) occurred within the Río Cruces wetland (southern Chile), a Ramsar Site and nature sanctuary. Before 2004, this wetland hosted the largest breeding population of this water bird in the Neotropic Realm. The concurrent decrease in the spatial occurrence of the aquatic plant Egeria densa Planch. 1849 - the main food source of swans - was proposed as a cause for swan migration and mortality. Additionally, post-mortem analyses carried out on swans during 2004 showed diminished body weight, high iron loads and histopathological abnormalities in their livers, suggesting iron storage disease. Various hypotheses were postulated to describe those changes; the most plausible related to variations in water quality after a pulp mill located upstream the wetland started to operate in February 2004. Those changes cascaded throughout the stands of E. densa whose remnants had high iron contents in their tissues. Here we present results of a long-term monitoring program of the wetland components, which show that swan population abundance, body weights and histological liver conditions recovered to pre-disturbance levels in 2012. The recovery of E. densa and iron content in plants throughout the wetland, also returned to pre-disturbance levels in the same 8-year time period. These results show the temporal scale over which resilience and natural restoring processes occur in wetland ecosystems of temperate regions such as southern Chile. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Triggered Slow Slip and Afterslip on the Southern Hikurangi Subduction Zone Following the Kaikōura Earthquake

    NASA Astrophysics Data System (ADS)

    Wallace, Laura M.; Hreinsdóttir, Sigrún; Ellis, Susan; Hamling, Ian; D'Anastasio, Elisabetta; Denys, Paul

    2018-05-01

    The 2016 MW7.8 Kaikōura earthquake ruptured a complex sequence of strike-slip and reverse faults in New Zealand's northeastern South Island. In the months following the earthquake, time-dependent inversions of Global Positioning System and interferometric synthetic aperture radar data reveal up to 0.5 m of afterslip on the subduction interface beneath the northern South Island underlying the crustal faults that ruptured in the earthquake. This is clear evidence that the far southern end of the Hikurangi subduction zone accommodates plate motion. The MW7.8 earthquake also triggered widespread slow slip over much of the subduction zone beneath the North Island. The triggered slow slip included immediate triggering of shallow (<15 km), short (2-3 weeks) slow slip events along much of the east coast, and deep (>30 km), long-term (>1 year) slow slip beneath the southern North Island. The southern Hikurangi slow slip was likely triggered by large (0.5-1.0 MPa) static Coulomb stress increases.

  8. Late quaternary paleoseismology of the southern Steens fault zone, northern Nevada

    USGS Publications Warehouse

    Personius, S.F.; Crone, A.J.; Machette, M.N.; Mahan, S.A.; Kyung, J.B.; Cisneros, H.; Lidke, D.J.

    2007-01-01

    The 192-km-long Steens fault zone is the most prominent normal fault system in the northern Basin and Range province of western North America. We use trench mapping and radiometric dating to estimate displacements and timing of the last three surface-rupturing earthquakes (E1-E3) on the southern part of the fault south of Denio, Nevada. Coseismic displacements range from 1.1 to 2.2 ?? 0.5 m, and radiometric ages indicate earthquake times of 11.5 ?? 2.0 ka (E3), 6.1 ?? 0.5 ka (E2), and 4.6 ?? 1.0 ka (E1). These data yield recurrence intervals of 5.4 ?? 2.1 k.y. between E3 and E2, 1.5 ?? 1.1 k.y. between E2 and E1, and an elapsed time of 4.6 ?? 1.0 k.y. since E1. The recurrence data yield variable interval slip rates (between 0.2 ?? 0.22 and 1.5 ?? 2.3 mm/yr), but slip rates averaged over the past ???18 k.y. (0.24 ?? 0.06 mm/year) are similar to long-term (8.5-12.5 Ma) slip rates (0.2 ?? 0.1 mm /yr) measured a few kilometers to the north. We infer from the lack of significant topographic relief across the fault in Bog Hot Valley that the fault zone is propagating southward and may now be connected with a fault at the northwestern end of the Pine Forest Range. Displacements documented in the trench and a rupture length of 37 km indicate a history of three latest Quaternary earthquakes with magnitudes of M 6.6-7.1 on the southern part of the Steens fault zone.

  9. Analysis and quantification of self-medication patterns of customers in community pharmacies in southern Chile.

    PubMed

    Fuentes Albarrán, Katherine; Villa Zapata, Lorenzo

    2008-12-01

    Self-medication refers to using drugs which have not been prescribed, recommended or controlled by a licensed health care specialist. Marketing, in Chile only admitted for over-the-counter medications, influences the practice of self-medication and extends it to prescription drugs. Thus, a complex self-medication process is started, due to reuse of a previous prescription, using drugs purchased directly at the pharmacy or drugs coming from family first-aid kits. The purpose of this study is to determine the frequency of self-medication, the type of medications involved, the dosages used, and the reasons for this practice. An observation-based cross-sectional study was carried out at three pharmacies belonging to a pharmacy chain in the city of Valdivia (southern Chile). In addition, a previously validated form was used. Customers who requested over-the-counter medications were surveyed to identify the patterns that foster the self-medication practice. Of 909 surveyed customers, 75% self-medicate. Of these, 31% stated that they commonly self-medicate due to suffering from light symptoms, such as headaches (19%), the common cold (8.8%), sore muscles (6.7%), and bone pains (5.3%). The group of medications most requested in this study was nonsteroidal anti-inflammatory drugs (NSAIDs) (33%), with diclofenac sodium being the most used (14%). Influence from other people did not exceed 20% and reusing prior prescriptions reached 46%. There were significant differences when assessing consumer knowledge, reading of information leaflets, and opinions about self-medication at each surveyed pharmacy (P < 0.001). Most consumers at the surveyed pharmacies use medications without proper knowledge of their benefits, treatment method, and duration. Drug dispensing at community pharmacies should include active pharmacist involvement to divulge the sensible use of drugs.

  10. Interdisciplinary studies of eruption at Chaiten Volcano, Chile

    Treesearch

    John S. Pallister; Jon J. Major; Thomas C. Pierson; Richard P. Hoblitt; Jacob B. Lowenstern; John C. Eichelberger; Lara Luis; Hugo Moreno; Jorge Munoz; Jonathan M. Castro; Andres Iroume; Andrea Andreoli; Julia Jones; Fred Swanson; Charlie Crisafulli

    2010-01-01

    There was keen interest within the volcanology community when the first large eruption of high-silica rhyolite since that of Alaska's Novarupta volcano in 1912 began on 1 May 2008 at Chaiten volcano, southern Chile, a 3-kilometer-diameter caldera volcano with a prehistoric record of rhyolite eruptions. Vigorous explosions occurred through 8 May 2008, after which...

  11. Genetic divergence analysis of the Common Barn Owl Tyto alba (Scopoli, 1769) and the Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile using COI sequence

    PubMed Central

    Colihueque, Nelson; Gantz, Alberto; Rau, Jaime Ricardo; Parraguez, Margarita

    2015-01-01

    Abstract In this paper new mitochondrial COI sequences of Common Barn Owl Tyto alba (Scopoli, 1769) and Short-eared Owl Asio flammeus (Pontoppidan, 1763) from southern Chile are reported and compared with sequences from other parts of the World. The intraspecific genetic divergence (mean p-distance) was 4.6 to 5.5% for the Common Barn Owl in comparison with specimens from northern Europe and Australasia and 3.1% for the Short-eared Owl with respect to samples from north America, northern Europe and northern Asia. Phylogenetic analyses revealed three distinctive groups for the Common Barn Owl: (i) South America (Chile and Argentina) plus Central and North America, (ii) northern Europe and (iii) Australasia, and two distinctive groups for the Short-eared Owl: (i) South America (Chile and Argentina) and (ii) north America plus northern Europe and northern Asia. The level of genetic divergence observed in both species exceeds the upper limit of intraspecific comparisons reported previously for Strigiformes. Therefore, this suggests that further research is needed to assess the taxonomic status, particularly for the Chilean populations that, to date, have been identified as belonging to these species through traditional taxonomy. PMID:26668551

  12. Effects of riparian zone buffer widths on vegetation diversity in southern Appalachian headwater catchments

    Treesearch

    Katherine J. Elliott; James M. Vose

    2016-01-01

    In mountainous areas such as the southern Appalachians USA, riparian zones are difficult to define. Vegetation is a commonly used riparian indicator and plays a key role in protecting water resources, but adequate knowledge of floristic responses to riparian disturbances is lacking. Our objective was to quantify changes in stand-level floristic diversity of...

  13. Evaluating satellite-derived long-term historical precipitation datasets for drought monitoring in Chile

    NASA Astrophysics Data System (ADS)

    Zambrano, Francisco; Wardlow, Brian; Tadesse, Tsegaye; Lillo-Saavedra, Mario; Lagos, Octavio

    2017-04-01

    Precipitation is a key parameter for the study of climate change and variability and the detection and monitoring of natural disaster such as drought. Precipitation datasets that accurately capture the amount and spatial variability of rainfall is critical for drought monitoring and a wide range of other climate applications. This is challenging in many parts of the world, which often have a limited number of weather stations and/or historical data records. Satellite-derived precipitation products offer a viable alternative with several remotely sensed precipitation datasets now available with long historical data records (+30years), which include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) datasets. This study presents a comparative analysis of three historical satellite-based precipitation datasets that include Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) 3B43 version 7 (1998-2015), PERSIANN-CDR (1983-2015) and CHIRPS 2.0 (1981-2015) over Chile to assess their performance across the country and for the case of the two long-term products the applicability for agricultural drought were evaluated when used in the calculation of commonly used drought indicator as the Standardized Precipitation Index (SPI). In this analysis, 278 weather stations of in situ rainfall measurements across Chile were initially compared to the satellite data. The study area (Chile) was divided into five latitudinal zones: North, North-Central, Central, South-Central and South to determine if there were a regional difference among these satellite products, and nine statistics were used to evaluate their performance to estimate the amount and spatial distribution of historical rainfall across Chile. Hierarchical cluster analysis, k-means and singular value decomposition were used to analyze

  14. Evaluating satellite-derived long-term historical precipitation datasets for drought monitoring in Chile

    NASA Astrophysics Data System (ADS)

    Zambrano, Francisco; Wardlow, Brian; Tadesse, Tsegaye

    2016-10-01

    Precipitation is a key parameter for the study of climate change and variability and the detection and monitoring of natural disaster such as drought. Precipitation datasets that accurately capture the amount and spatial variability of rainfall is critical for drought monitoring and a wide range of other climate applications. This is challenging in many parts of the world, which often have a limited number of weather stations and/or historical data records. Satellite-derived precipitation products offer a viable alternative with several remotely sensed precipitation datasets now available with long historical data records (+30 years), which include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) datasets. This study presents a comparative analysis of three historical satellite-based precipitation datasets that include Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) 3B43 version 7 (1998-2015), PERSIANN-CDR (1983-2015) and CHIRPS 2.0 (1981-2015) over Chile to assess their performance across the country and evaluate their applicability for agricultural drought evaluation when used in the calculation of commonly used drought indicator as the Standardized Precipitation Index (SPI). In this analysis, 278 weather stations of in-situ rainfall measurements across Chile were initially compared to the satellite-based precipitation estimates. The study area (Chile) was divided into five latitudinal zones: North, North-Central, Central, South-Central and South to determine if there were a regional difference among these satellite-based estimates. Nine statistics were used to evaluate the performance of satellite products to estimate the amount and spatial distribution of historical rainfall across Chile. Hierarchical cluster analysis, k-means and singular value decomposition were used to

  15. Quantifying Vertical Exhumation in Intracontinental Strike-Slip Faults: the Garlock fault zone, southern California

    NASA Astrophysics Data System (ADS)

    Chinn, L.; Blythe, A. E.; Fendick, A.

    2012-12-01

    New apatite fission-track ages show varying rates of vertical exhumation at the eastern terminus of the Garlock fault zone. The Garlock fault zone is a 260 km long east-northeast striking strike-slip fault with as much as 64 km of sinistral offset. The Garlock fault zone terminates in the east in the Avawatz Mountains, at the intersection with the dextral Southern Death Valley fault zone. Although motion along the Garlock fault west of the Avawatz Mountains is considered purely strike-slip, uplift and exhumation of bedrock in the Avawatz Mountains south of the Garlock fault, as recently as 5 Ma, indicates that transpression plays an important role at this location and is perhaps related to a restricting bend as the fault wraps around and terminates southeastward along the Avawatz Mountains. In this study we complement extant thermochronometric ages from within the Avawatz core with new low temperature fission-track ages from samples collected within the adjacent Garlock and Southern Death Valley fault zones. These thermochronometric data indicate that vertical exhumation rates vary within the fault zone. Two Miocene ages (10.2 (+5.0/-3.4) Ma, 9.0 (+2.2/-1.8) Ma) indicate at least ~3.3 km of vertical exhumation at ~0.35 mm/yr, assuming a 30°C/km geothermal gradient, along a 2 km transect parallel and adjacent to the Mule Spring fault. An older Eocene age (42.9 (+8.7/-7.3) Ma) indicates ~3.3 km of vertical exhumation at ~0.08 mm/yr. These results are consistent with published exhumation rates of 0.35 mm/yr between ~7 and ~4 Ma and 0.13 mm/yr between ~15 and ~9 Ma, as determined by apatite fission-track and U-Th/He thermochronometry in the hanging-wall of the Mule Spring fault. Similar exhumation rates on both sides of the Mule Spring fault support three separate models: 1) Thrusting is no longer active along the Mule Spring fault, 2) Faulting is dominantly strike-slip at the sample locations, or 3) Miocene-present uplift and exhumation is below detection levels

  16. Evidence for an upper mantle low velocity zone beneath the southern Basin and Range-Colorado Plateau transition zone

    USGS Publications Warehouse

    Benz, H.M.; McCarthy, J.

    1994-01-01

    A 370-km-long seismic refraction/wide-angle reflection profile recorded during the Pacific to Arizona Crustal Experiment (PACE) detected an upper mantle P-wave low-velocity zone (LVZ) in the depth range 40 to 55 km beneath the Basin and Range in southern Arizona. Interpretation of seismic data places constraints on the sub-crustal lithosphere of the southern Basin and Range Province, which is important in light of the active tectonics of the region and the unknown role of the sub-crustal lithosphere in the development of the western United States. Forward travel time and synthetic seismogram techniques are used to model this shallow upper mantle LVZ. Modeling results show that the LVZ is defined by a 5% velocity decrease relative to a Pn velocity of 7.95 km s−1, suggesting either a ∼3–5% mafic partial melt or high-temperature, sub-solidus peridotite.

  17. The Early Toarcian Oceanic Anoxic Event: A Southern Hemisphere record from Chile

    NASA Astrophysics Data System (ADS)

    Fantasia, Alicia; Föllmi, Karl B.; Adatte, Thierry; Spangenberg, Jorge E.; Bernárdez, Enrique; Mattioli, Emanuela

    2016-04-01

    The Early Toarcian was marked by important environmental changes, marine oxygen deficiency and extensive organic-rich sediment deposition (T-OAE; ˜182 Ma, Early Jurassic). The T-OAE coincides with a marked negative carbon isotope excursion (CIE) recorded in marine carbonate, and marine and terrestrial organic carbon. This is commonly attributed to the massive release of isotopically light carbon to the atmospheric and oceanic reservoirs derived from the destabilization of methane hydrates from marine sediments and/or the emissions of thermogenic methane from the eruption of the Karoo-Ferrar LIP (e.g., Hesselbo et al., 2000; Kemp et al., 2005; Svensen et al., 2007; Mazzini et al., 2010). Moreover, in most documented marine sections, this episode is marked by a generalized crisis in carbonate production and marine invertebrate extinctions (e.g. Jenkyns, 1988; Röhl et al., 2005; Suan et al., 2001). Several studies of the T-OAE have been conducted on sediments in central and northwest Europe, but only few data are available from the Southern Hemisphere, leading to large uncertainty concerning the exact expression of this event in this part of the world. The aims of this study are to characterize the sediments deposited during the Andean equivalents of the tenuicostatum and falciferum European Zones and establish in which way the T-OAE affected this region. In the Early Jurassic, the Andean basin was in a back-arc setting with marine corridors connected to Panthalassa. In this study, we have generated new high-resolution sedimentological, geochemical and mineralogical data from the sections of El Peñon and Quebrada Asiento, located in Chile in the northeastern area of the city of Copiapó, Atacama region. The biostratigraphy of these sections has been studied by von Hillebrandt and Schidt-Effing (1981) and complemented here by a biostratigraphy based on calcareous nannofossils. The sections consist of a succession of marl, limestone and siltstone of Pliensbachian and

  18. Diffuse Extension of the Southern Mariana Margin: Implications for Subduction Zone Infancy and Plate Tectonics

    NASA Astrophysics Data System (ADS)

    Martinez, F.; Stern, R. J.; Kelley, K. A.; Ohara, Y.; Sleeper, J. D.; Ribeiro, J. M.; Brounce, M. N.

    2017-12-01

    Opening of the southern Mariana margin takes place in contrasting modes: Extension normal to the trench forms crust that is passively accreted to a rigid Philippine Sea plate and forms along focused and broad accretion axes. Extension also occurs parallel to the trench and has split apart an Eocene-Miocene forearc terrain accreting new crust diffusely over a 150-200 km wide zone forming a pervasive volcano-tectonic fabric oriented at high angles to the trench and the backarc spreading center. Earthquake seismicity indicates that the forearc extension is active over this broad area and basement samples date young although waning volcanic activity. Diffuse formation of new oceanic crust and lithosphere is unusual; in most oceanic settings extension rapidly focuses to narrow plate boundary zones—a defining feature of plate tectonics. Diffuse crustal accretion has been inferred to occur during subduction zone infancy, however. We hypothesize that, in a near-trench extensional setting, the continual addition of water from the subducting slab creates a weak overriding hydrous lithosphere that deforms broadly. This process counteracts mantle dehydration and strengthening proposed to occur at mid-ocean ridges that may help to focus deformation and melt delivery to narrow plate boundary zones. The observations from the southern Mariana margin suggest that where lithosphere is weakened by high water content narrow seafloor spreading centers cannot form. These conditions likely prevail during subduction zone infancy, explaining the diffuse contemporaneous volcanism inferred in this setting.

  19. Earthquakes in Fiordland, Southern Chile: Initiation and Development of a Magmatic Process

    NASA Astrophysics Data System (ADS)

    Barrientos, S.; Service, N. S.

    2007-05-01

    Several efforts in Chile are being conducted in relation to geophysical monitoring with the objective of disaster mitigation. A long and permanent monitoring effort along the country has been the continuous effort resulting in the recognition and delineation of new seismogenic sources. Here we report on the seismo-volcanic crisis that is currently taking place in the in the region close to the triple junction (Nazca, Antarctica and South America) in southern Chile at around latitude 45°S. On January 22, 2007, an intensity V-VI (MMI) earthquake shook the cities of Puerto Aysén, Puerto Chacabuco and Coyhaique. This magnitude 5 event, was the first of a series of earthquakes that have taken place in the region for nearly a month and a half (until end of February, time when this abstract was written). The closest station to the source area -part of the GEOSCOPE network located in Coyhaique, about 80 km away from the epicenters- reveals seismic activity about 3 hours before the first event. Immediately after the first event, more than 20 events per hour were detected and recorded by this station, rate which decreased with time with the exception of those time intervals following larger events. More than six events with magnitude 5 or more have been recorded. Five seismic stations were installed surrounding the epicentral area between 27 - 29 January and are currently operational. After processing some of the recorded events, a sixth station was installed at the closest possible site of the source of the seismic activity. Preliminary analysis of the recorded seismic activity reveals a concentration of hypocenters - 5 to 10 km depth- along an eight-km NNE-SSW vertical plane crossing the Aysén fiord. Harmonic tremor has also been detected. This seismic activity is interpreted as the result of a magmatic process in progress which will most likely culminate in the generation of a new underwater volcanic edifice. Because the seismic activity fully extends across the Ays

  20. Rapid uplift during 2007-2012 at Laguna del Maule volcanic field, Andean Southern Volcanic Zone, Chile

    NASA Astrophysics Data System (ADS)

    Le Mevel, H.; Feigl, K.; Ali, T.; Cordova V., M. L.; DeMets, C.; Singer, B. S.

    2012-12-01

    The Laguna del Maule (LdM) volcanic field includes an unusual concentration of post-glacial rhyolitic lava coulees and domes, dated between 24 to 2 thousand years old that cover more than 100 square kilometers and erupted from 24 vents that encircle a 20-km-diameter lake basin on the range crest. The recent concentration of rhyolite is unparalleled in the Southern Volcanic Zone of the Andes. Moreover, the western portion of the LdM volcanic field has experienced rapid uplift since 2007, leading to questions about the current configuration of the magmatic system and processes that drive the ongoing inflation. We aim to quantify the active deformation of the LdM volcanic field and its evolution with time. To do so, we use interferometric synthetic aperture radar (InSAR) data acquired by three satellite missions: Envisat in 2003 and 2004, ALOS between 2007 and 2010, and TerraSAR-X in 2012. An interferogram spanning March 2003 to February 2004 "shows no deformation" (Fournier et al., 2010). From 2007 through 2012, however, the shortening of the satellite-to-ground distance revealed a range change rate of greater than 200 mm/yr along the radar line of sight. The deformation includes a circular area 20 km in diameter centered on the western portion of the circle of young rhyolite domes. To analyze the InSAR results, we employ the General Inversion for Phase Technique (GIPhT; Feigl and Thurber, 2009; Ali and Feigl, 2012). We have considered several hypotheses to interpret this deformation. Artefacts such as orbital errors, atmospheric perturbations or topographic contribution cannot account for the observed signal. We also reject the hypothesis of uplift due to gravitational unloading of the crust based on our modeling of independently measured lake level variations over the observed time interval. We thus attribute the deformation to the intrusion of magma into the upper crust below the southwest region of the LdM volcanic field. The best fit to the InSAR data is

  1. Toxoplasma gondii in feral american minks at the Maullin river, Chile

    USDA-ARS?s Scientific Manuscript database

    American mink (Neovison vison) is a widely distributed invasive species in southern Chile. Thirty four feral minks were trapped at two distinct sites (rural and peri-urban), diet analyzed, and Toxoplasma gondii exposure compared using PCR and specific antibodies. Serum samples were evaluated using a...

  2. Indoor PM2.5 in an urban zone with heavy wood smoke pollution: The case of Temuco, Chile.

    PubMed

    Jorquera, Héctor; Barraza, Francisco; Heyer, Johanna; Valdivia, Gonzalo; Schiappacasse, Luis N; Montoya, Lupita D

    2018-05-01

    Temuco is a mid-size city representative of severe wood smoke pollution in southern Chile; however, little is known about the indoor air quality in this region. A field measurement campaign at 63 households in the Temuco urban area was conducted in winter 2014 and is reported here. In this study, indoor and outdoor (24-hr) PM 2.5 and its elemental composition were measured and compared. Infiltration parameters and outdoor/indoor contributions to indoor PM 2.5 were also determined. A statistical evaluation of how various air quality interventions and household features influence indoor PM 2.5 was also performed. This study determined median indoor and outdoor PM 2.5 concentrations of 44.4 and 41.8 μg/m 3 , respectively. An average infiltration factor (0.62 ± 0.06) was estimated using sulfur as a tracer species. Using a simple mass balance approach, median indoor and outdoor contributions to indoor PM 2.5 concentrations were then estimated as 12.5 and 26.5 μg/m 3 , respectively; therefore, 68% of indoor PM 2.5 comes from outdoor infiltration. This high percentage is due to high outdoor pollution and relatively high household air exchange rates (median: 1.06 h -1 ). This study found that S, Br and Rb were dominated by outdoor contributions, while Si, Ca, Ti, Fe and As originated from indoor sources. Using continuous indoor and outdoor PM 2.5 measurements, a median indoor source strength of 75 μg PM 2.5 /min was estimated for the diurnal period, similar to literature results. For the evening period, the median estimate rose to 135 μg PM 2.5 /min, reflecting a more intense wood burning associated to cooking and space heating at night. Statistical test results (at the 90% confidence level) support the ongoing woodstove replacement program (reducing emissions) and household weatherization subsidies (reducing heating demand) for improving indoor air quality in southern Chile, and suggest that a cookstove improvement program might be helpful as well

  3. Ecology, genetic diversity, and phylogeographic structure of andes virus in humans and rodents in Chile.

    PubMed

    Medina, Rafael A; Torres-Perez, Fernando; Galeno, Hector; Navarrete, Maritza; Vial, Pablo A; Palma, R Eduardo; Ferres, Marcela; Cook, Joseph A; Hjelle, Brian

    2009-03-01

    Andes virus (ANDV) is the predominant etiologic agent of hantavirus cardiopulmonary syndrome (HCPS) in southern South America. In Chile, serologically confirmed human hantavirus infections have occurred throughout a wide latitudinal distribution extending from the regions of Valparaíso (32 to 33 degrees S) to Aysén (46 degrees S) in southern Patagonia. In this study, we found seropositive rodents further north in the Coquimbo region (30 degrees S) in Chile. Rodent seroprevalence was 1.4%, with Oligoryzomys longicaudatus displaying the highest seroprevalence (5.9%), followed by Abrothrix longipilis (1.9%) and other species exhibiting Chile. Phylogenetic analyses showed two major ANDV South (ANDV Sout) clades, congruent with two major Chilean ecoregions, Mediterranean (Chilean matorral [shrubland]) and Valdivian temperate forest. Human and rodent samples grouped according to geographic location. Phylogenetic comparative analyses of portions of S and medium segments (encoding glycoproteins Gn and Gc) from a subset of rodent specimens exhibited similar topologies, corroborating two major ANDV Sout clades in Chile and suggesting that yet unknown factors influence viral gene flow and persistence throughout the two Chilean ecoregions. Genetic algorithms for recombination detection identified recombination events within the S segment. Molecular demographic analyses showed that the virus is undergoing purifying selection and demonstrated a recent exponential growth in the effective number of ANDV Sout infections in Chile that correlates with the increased number of human cases reported. Although we determined virus sequences from four rodent species, our results confirmed O. longicaudatus as the primary ANDV Sout reservoir in Chile. While evidence of geographic differentiation

  4. Structure of a seismogenic fault zone in dolostones: the Foiana Line (Italian Southern Alps)

    NASA Astrophysics Data System (ADS)

    Di Toro, G.; Fondriest, M.; Smith, S. A.; Aretusini, S.

    2012-12-01

    Fault zones in carbonate rocks (limestones and dolostones) represent significant upper crustal seismogenic sources in several areas worldwide (e.g. L'Aquila 2009 Mw = 6.3 in central Italy). Here we describe an exhumed example of a regionally-significant fault zone cutting dolostones. The Foiana Line (FL) is a major NNE-SSW-trending sinistral transpressive fault cutting sedimentary Triassic dolostones in the Italian Southern Alps. The FL has a cumulative vertical throw of 1.5-2 km that reduces toward its southern termination. The fault zone is 50-300 m wide and is exposed for ~ 10 km along strike within several outcrops exhumed from increasing depths from the south (1 km) to the north (2.5 km). The southern portion of the FL consists of heavily fractured (shattered) dolostones, with particles of a few millimeters in size (exposed in badlands topography over an area of 6 km2), cut by a dense network of 1-20 m long mirror-like fault surfaces with dispersed attitudes. The mirror-like faults have mainly dip-slip reverse kinematics and displacements ranging between 0.04 m and 0.5 m. The northern portion of the FL consists of sub-parallel fault strands spaced 2-5 m apart, surrounded by 2-3 m thick bands of shattered dolostones. The fault strands are characterized by smooth to mirror-like sub-vertical slip surfaces with dominant strike-slip kinematics. Overall, deformation is more localized moving from South to North along the FL. Mirror-like fault surfaces similar to those found in the FL were produced in friction experiments at the deformation conditions expected during seismic slip along the FL (Fondriest et al., this meeting). Scanning Electron Microscope investigations of the natural shattered dolostones beneath the mirror-like fault surfaces show: 1) lack of significant shear strain (even at a few micrometers from the slip surface), 2) pervasive extensional fracturing down to the micrometer scale, 3) exploded clasts with radial fractures, and 4) chains of split

  5. Sonograph mosaic of northern California and southern Oregon Exclusive Economic Zone

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cacchione, D.A.; Drake, D.E.; Clarke, S.H.

    1985-02-01

    During June 15 to July 9, 1984, the third leg of the cooperative US Geological Survey-Institute of Oceanographic Sciences GLORIA survey of the conterminous US Exclusive Economic Zone (EEZ) collected digital acoustic data off northern California and southern Oregon. The region covered during leg 3 extends from the 200-m isobath westward to the 375-km (200-nmi) EEZ boundary and from about 39/sup 0/ to 43/sup 0/N. The survey used the IOS GLORIA long-range side-scan sonar, a 2-channel airgun seismic reflection system, and 3.5 kHz and 10 kHz high-resolution seismic systems. The GLORIA data were collected in a pattern that permitted overlappingmore » coverage so that a mosaic of the sonographs could be constructed. These sonographs were slant-range and anamorphically corrected aboard ship, and a mosaic was constructed at a scale of 1:375,000. Among the most striking geomorphic features revealed in this segment of the EEZ is the Mendocino transform fault, which extends for more than 120 nmi along the northern base of the Mendocino fracture zone and delineates the southern boundary of the Gorda plate. Other features clearly revealed are the complex geometry of the Gorda rift valley, and the subparallel flanking ridges and dramatically deformed base of the continental slope at the eastern boundary of the Gorda plate. The data are presently being processed by image analytical techniques to enhance the fine-scale features such as sediment waves, slumps, and areas of differing sedimentary facies.« less

  6. Large slope instabilities in Northern Chile and Southern Peru

    NASA Astrophysics Data System (ADS)

    Crosta, Giovanni B.; Hermanns, Reginald L.; Valbuzzi, Elena; Frattini, Paolo; Valagussa, Andrea

    2014-05-01

    Deep canyon incision into Tertiary paleosurfaces and large slope instabilities along the canyon flanks characterize the landscape of western slope of the Andes of northern Chile and South Peru. This area belongs to the Coastal Escarpment and Precordillera and is formed by coarse-grained clastic and volcanoclastic formations. The area is characterized by intense seismicity and long-term hyperaridity (Atacama Desert). Landslides along the canyon flanks affect volumes generally up to 1 km3 and locally evolved in large rock avalanches. We prepared a landslide inventory covering an area of about 30,000 km2, extending from Iquique (Chile) to the South and Tacna (Peru) to the North. A total of 606 landslides have been mapped in the area by use of satellite images and direct field surveys, prevalently including large phenomena. The landslides range from 1 10-3 km2 to 464 km2 (Lluta landslide). The total landslide area, inclusive of the landslide scarp and of the deposit, amounts to about 2,130 km2 (about 7% of the area). The mega landslides can be classified as large block slides that can evolve in large rock avalanches (e.g. Minimini landslide). Their initiation seems to be strongly associated to the presence of secondary faults and large fractures transversal to the slope. These landslides show evidence suggesting a re-incision by the main canyon network. This seems particularly true for the Lluta collapse where the main 'landslide' mass is masked or deleted by the successive erosion. Other landslides have been mapped along the Coastal Escarpment and some of the major tectonic escarpments with an E-W trend. We examined area-frequency distributions of landslides by developing logarithmically binned, non-cumulative size frequency distributions that report frequency density as a function of landslide planar area A. The size frequency distribution presents a strong undersampling for smaller landslides, due to the extremely old age of the inventory. For landslides larger than

  7. Variability of 14C reservoir age and air-sea flux of CO2 in the Peru-Chile upwelling region during the past 12,000 years

    NASA Astrophysics Data System (ADS)

    Carré, Matthieu; Jackson, Donald; Maldonado, Antonio; Chase, Brian M.; Sachs, Julian P.

    2016-01-01

    The variability of radiocarbon marine reservoir age through time and space limits the accuracy of chronologies in marine paleo-environmental archives. We report here new radiocarbon reservoir ages (ΔR) from the central coast of Chile ( 32°S) for the Holocene period and compare these values to existing reservoir age reconstructions from southern Peru and northern Chile. Late Holocene ΔR values show little variability from central Chile to Peru. Prior to 6000 cal yr BP, however, ΔR values were markedly increased in southern Peru and northern Chile, while similar or slightly lower-than-modern ΔR values were observed in central Chile. This extended dataset suggests that the early Holocene was characterized by a substantial increase in the latitudinal gradient of marine reservoir age between central and northern Chile. This change in the marine reservoir ages indicates that the early Holocene air-sea flux of CO2 could have been up to five times more intense than in the late Holocene in the Peruvian upwelling, while slightly reduced in central Chile. Our results show that oceanic circulation changes in the Humboldt system during the Holocene have substantially modified the air-sea carbon flux in this region.

  8. Link between the double-Intertropical Convergence Zone problem and cloud biases over the Southern Ocean

    PubMed Central

    Hwang, Yen-Ting; Frierson, Dargan M. W.

    2013-01-01

    The double-Intertropical Convergence Zone (ITCZ) problem, in which excessive precipitation is produced in the Southern Hemisphere tropics, which resembles a Southern Hemisphere counterpart to the strong Northern Hemisphere ITCZ, is perhaps the most significant and most persistent bias of global climate models. In this study, we look to the extratropics for possible causes of the double-ITCZ problem by performing a global energetic analysis with historical simulations from a suite of global climate models and comparing with satellite observations of the Earth’s energy budget. Our results show that models with more energy flux into the Southern Hemisphere atmosphere (at the top of the atmosphere and at the surface) tend to have a stronger double-ITCZ bias, consistent with recent theoretical studies that suggest that the ITCZ is drawn toward heating even outside the tropics. In particular, we find that cloud biases over the Southern Ocean explain most of the model-to-model differences in the amount of excessive precipitation in Southern Hemisphere tropics, and are suggested to be responsible for this aspect of the double-ITCZ problem in most global climate models. PMID:23493552

  9. Vascular plant flora of the alpine zone in the southern Rocky Mountains, U.S.A

    Treesearch

    James F. Fowler; B. E. Nelson; Ronald L. Hartman

    2014-01-01

    Field detection of changes in occurrence, distribution, or abundance of alpine plant species is predicated on knowledge of which species are in specific locations. The alpine zone of the Southern Rocky Mountain Region has been systematically inventoried by the staff and floristics graduate students from the Rocky Mountain Herbarium over the last 27 years. It is...

  10. The San Gabriel mountains bright reflective zone: Possible evidence of young mid-crustal thrust faulting in southern California

    USGS Publications Warehouse

    Ryberg, T.; Fuis, G.S.

    1998-01-01

    During the Los Angeles Region Seismic Experiment (LARSE), a reflection/retraction survey was conducted along a line extending northeastward from Seal Beach, California, to the Mojave Desert, crossing the Los Angeles basin and San Gabriel Mountains. Shots and receivers were spaced most densely through the San Gabriel Mountains for the purpose of obtaining a combined reflection and refraction image of the crust in that area. A stack of common-midpoint (CMP) data reveals a bright reflective zone, 1-s thick, that dominates the stack and extends throughout most of the mid-crust of the San Gabriel Mountains. The top of this zone ranges in depth from 6 s (???18-km depth) in the southern San Gabriel Mountains to 7.5 s (???23-km depth) in the northern San Gabriel Mountains. The zone bends downward beneath the surface traces of the San Gabriel and San Andreas faults. It is brightest between these two faults, where it is given the name San Gabriel Mountains 'bright spot' (SGMBS). and becomes more poorly defined south of the San Gabriel fault and north of the San Andreas fault. The polarity of the seismic signal at the top of this zone is clearly negative, and our analysis suggests it represents a negative velocity step. The magnitude of the velocity step is approximately 1.7 km/s. In at least one location, an event with positive polarity can be observed 0.2 s beneath the top of this zone, indicating a thickness of the order of 500 m for the low-velocity zone at this location. Several factors combine to make the preferred interpretation of this bright reflective zone a young fault zone, possibly a 'master' decollement. (1) It represents a significant velocity reduction. If the rocks in this zone contain fluids, such a reduction could be caused by a differential change in fluid pressure between the caprock and the rocks in the SGMBS; near-lithostatic fluid pressure is required in the SGMBS. Such differential changes are believed to occur in the neighborhood of active fault

  11. Total factor productivity change in dairy farming: Empirical evidence from southern Chile.

    PubMed

    Moreira, Víctor H; Bravo-Ureta, Boris E

    2016-10-01

    Despite the importance of productivity growth, many studies carried out at the farm level focus primarily on the technical efficiency (TE) component of farm productivity. Therefore, the general purpose of this paper is to measure total factor productivity change and then to decompose this change into several distinct elements. The data were an unbalanced panel for the period from 2005 to 2010 containing 477 farms and 1,426 observations obtained from TODOAGRO, a farm-management center created in 1996 in the southern part of Chile. The region where the data come from accounts for 20% of the total milk processed in the country. Stochastic production frontiers along with the translog functional form were used to analyze total factor productivity change. The econometric evidence indicates that farms exhibit decreasing returns to size implying that costs of production rise as farm size increases, which suggests that the motivation for farm growth stems from the search for income rather than from lowering costs. The main results indicated that productivity gains through TE improvements are limited, with an average TE for the whole sample of 91.0%, and average technical efficiency change of 0.05% per year. By contrast, average technological progress at the sample mean was rather high at 1.90%, which suggests that additional investments in research and subsequent adoption of improved technologies would have a positive effect on productivity growth. The findings also revealed that farm size is not associated with productivity growth for the dairy farms in the sample. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  12. Recent climate variations in Chile: constraints from borehole temperature profiles

    NASA Astrophysics Data System (ADS)

    Pickler, Carolyne; Gurza Fausto, Edmundo; Beltrami, Hugo; Mareschal, Jean-Claude; Suárez, Francisco; Chacon-Oecklers, Arlette; Blin, Nicole; Cortés Calderón, Maria Teresa; Montenegro, Alvaro; Harris, Rob; Tassara, Andres

    2018-04-01

    We have compiled, collected, and analyzed 31 temperature-depth profiles from boreholes in the Atacama Desert in central and northern Chile. After screening these profiles, we found that only nine profiles at four different sites were suitable to invert for ground temperature history. For all the sites, no surface temperature variations could be resolved for the period 1500-1800. In the northern coastal region of Chile, there is no perceptible temperature variation at all from 1500 to present. In the northern central Chile region, between 26 and 28° S, the data suggest a cooling from ≈ 1850 to ≈ 1980 followed by a 1.9 K warming starting ≈ 20-40 years BP. This result is consistent with the ground surface temperature histories for Peru and the semiarid regions of South America. The duration of the cooling trend is poorly resolved and it may coincide with a marked short cooling interval in the 1960s that is found in meteorological records. The total warming is greater than that inferred from proxy climate reconstructions for central Chile and southern South America, and by the PMIP3-CMIP5 surface temperature simulations for the north-central Chile grid points. The differences among different climate reconstructions, meteorological records, and models are likely due to differences in spatial and temporal resolution among the various data sets and the models.

  13. Seismicity and structure of Nazca Plate subduction zone in southern Peru

    NASA Astrophysics Data System (ADS)

    Lim, H.; Kim, Y.; Clayton, R. W.

    2015-12-01

    We image the Nazca plate subduction zone system by detecting and (re)locating intra-slab earthquakes in southern Peru. Dense seismic arrays (PeruSE, 2013) were deployed along four lines to target geophysical characterization of the subduction system in the transition zone between flat and normal dipping segments of the Nazca plate (2-15°S). The arc volcanism is absent near the flat slab segment, and currently, the correlation between the location of the active volcanic front and corresponding slab depth is neither clear nor consistent between previously published models from seismicity. We detect 620 local earthquakes from August 2008 to February 2013 by manually picking 6559 and 4145 arrival times for P- and S-phases, respectively. We observe that the S-phase data is helpful to reduce the trade-off between origin time and depth of deeper earthquakes (>100 km). Earthquake locations are relocated to constrain the Nazca slab-mantle interface in the slab-dip transition zone using 7322 measurements of differential times of nearby earthquake pairs by waveform cross-correlation. We also employ the double-difference tomography (Zhang and Thurber, 2003) to further improve earthquake source locations and the spatial resolution of the velocity structure simultaneously. The relocated hypocenters clearly delineate the dipping Wadati-Benioff zone in the slab-dip transition zone between the shallow- (25°) to-flat dipping slab segment in the north and the normal (40°) dipping segment in the south. The intermediate-depth seismicity in the flat slab region stops at a depth of ~100 km and a horizontal distance of ~400 km from the trench. We find a significant slab-dip difference (up to 10°) between our relocated seismicity and previously published slab models along the profile region sampling the normal-dip slab at depth (>100 km).

  14. Shallow depth of seismogenic coupling in southern Mexico: implications for the maximum size of earthquakes in the subduction zone

    NASA Astrophysics Data System (ADS)

    Suárez, Gerardo; Sánchez, Osvaldo

    1996-01-01

    Studies of locally recorded microearthquakes and the centroidal depths of the largest earthquakes analyzed using teleseismic data show that the maximum depth of thrust faulting along the Mexican subduction zone is anomalously shallow. This observed maximum depth of about 25 ± 5 km is about half of that observed in most subduction zones of the world. A leveling line that crosses the rupture zone of the 19 September 1985 Michoacan event was revisited after the earthquake and it shows anomalously low deformation during the earthquake. The comparison between the observed coseismic uplift and dislocation models of the seismogenic interplate contact that extend to depths ranging from 20 to 40 km shows that the maximum depth at which seismic slip took place is about 20 km. This unusually shallow and narrow zone of seismogenic coupling apparently results in the occurrence of thrust events along the Mexican subduction zone that are smaller than would be expected for a trench where a relatively young slab subducts at a rapid rate of relative motion. A comparison with the Chilean subduction zone shows that the plate interface in Mexico is half that in Chile, not only in the down-dip extent of the seismogenic zone of plate contact, but also in the distance of the trench from the coast and in the thickness of the upper continental plate. It appears that the narrow plate contact produced by this particular plate geometry in Mexico is the controlling variable defining the size of the largest characteristic earthquakes in the Mexican subduction zone.

  15. Interactions of Marine Hydrokinetic Devices in Complex Bathymetries: Numerical Simulations in the Chacao Channel in Southern Chile.

    NASA Astrophysics Data System (ADS)

    Soto, K. A.; Escauriaza, C. R.; Richter, D. H.

    2015-12-01

    Many coastal areas in the South Pacific Ocean can provide significant marine energy resources in the near future. The installation of marine hydrokinetic (MHK) devices in these regions will require new approaches to understand physical and environmental processes that are relevant for the installation of turbine arrays, which are also specific of each site. The coastal morphology of the Chacao channel in southern Chile, which separates the Chiloé island from the main continent (41º47'S, 73º31'W) stands out as an important energy resource that can potentially contribute a significant power capacity. This coastal area not only sustains delicate ecosystems with limited anthropic intervention, but it is characterized by a complex bathymetry that can have important effects on the performance of MHK devices and their local impacts. To understand the interactions of the local bathymetry and ambient turbulence with turbine arrays, we carry out a series of numerical simulations with a coherent-structure resolving turbulence model using the actuator disk parameterization. The main objective of this study is to further our understanding on the physical processes associated with the installation of the turbine arrays. We perform simulations with different geometries and inlet boundary conditions, from simple cases in a rectangular channel, to more complex cases that include the high-resolution bathymetry of an extensive area of the Chacao channel. The results show how the interactions between the MHK devices, the local flow, and the bed can affect the energy flux and potential generation in specific sites. The results also provide new insights of local impacts of MHK devices and they can also help to optimize turbine arrays in natural environments. This work has been supported by Fondecyt project 1130940, and the Marine Energy Research & Innovation Center (MERIC) financed by Corfo and based in Santiago, Chile.

  16. Along-strike variability of primitive magmas (major and volatile elements) inferred from olivine-hosted melt inclusions, southernmost Andean Southern Volcanic Zone, Chile

    NASA Astrophysics Data System (ADS)

    Weller, D. J.; Stern, C. R.

    2018-01-01

    Glass compositions of melt inclusions in olivine phenocrysts found in tephras derived from explosive eruptions of the four volcanoes along the volcanic front of the southernmost Andean Southern Volcanic Zone (SSVZ) are used to constrain primitive magma compositions and melt generation parameters. Primitive magmas from Hudson, Macá, and Melimoyu have similar compositions and are formed by low degrees (8-18%) of partial melting. Compared to these other three centers, primitive magmas from Mentolat have higher Al2O3 and lower MgO, TiO2 and other incompatible minor elements, and are generated by somewhat higher degrees (12-20%) of partial melting. The differences in the estimated primitive parental magma compositions between Mentolat and the other three volcanic centers are consistent with difference in the more evolved magmas erupted from these centers, Mentolat magmas having higher Al2O3 and lower MgO, TiO2 and other incompatible minor element contents, suggesting that these differences are controlled by melting processes in the mantle source region above the subducted oceanic plate. Parental magma S = 1430-594 and Cl = 777-125 (μg/g) contents of Hudson, Macá, and Melimoyu are similar to other volcanoes further north in the SVZ. However, Mentolat primitive magmas have notably higher concentrations of S = 2656-1227 and Cl = 1078-704 (μg/g). The observed along-arc changes in parental magma chemistry may be due to the close proximity below Mentolat of the subducted Guamblin Fracture Zone that could efficiently transport hydrous mineral phases, seawater, and sediment into the mantle, driving enhanced volatile fluxed melting beneath this center compared to the others. Table S2. Olivine-hosted melt inclusion compositions, host-olivine compositions, and the post-entrapment crystallization corrected melt inclusion compositions. Table S3. Olivine-hosted melt inclusion modeling information. Table S4. Major element compositions of the fractionation corrected melt inclusion

  17. An outbreak of hantavirus pulmonary syndrome, Chile, 1997.

    PubMed Central

    Toro, J.; Vega, J. D.; Khan, A. S.; Mills, J. N.; Padula, P.; Terry, W.; Yadón, Z.; Valderrama, R.; Ellis, B. A.; Pavletic, C.; Cerda, R.; Zaki, S.; Shieh, W. J.; Meyer, R.; Tapia, M.; Mansilla, C.; Baro, M.; Vergara, J. A.; Concha, M.; Calderon, G.; Enria, D.; Peters, C. J.; Ksiazek, T. G.

    1998-01-01

    An outbreak of 25 cases of Andes virus-associated hantavirus pulmonary syndrome (HPS) was recognized in southern Chile from July 1997 through January 1998. In addition to the HPS patients, three persons with mild hantaviral disease and one person with asymptomatic acute infection were identified. Epidemiologic studies suggested person-to-person transmission in two of three family clusters. Ecologic studies showed very high densities of several species of sigmodontine rodents in the area. PMID:9866751

  18. The transition zone below the Chile-Argentina flat subduction region

    NASA Astrophysics Data System (ADS)

    Bonatto, Luciana; Piromallo, Claudia; Badi, Gabriela

    2017-04-01

    We study the fine structure of the upper mantle (below 200 km depth) beneath the western margin of South America, within an area known as the Chile-Argentina flat subduction zone (between 26°S and 36°S). Unlike what happens in most subduction zones, in this region the Nazca Plate subducts with an angle close to the horizontal -initially dips underneath the continent and flattens at a depth of approximately 100 km, remaining almost horizontal for about 300 km before descending more steeply into the mantle. Moreover, the flat slab follows the path of the subducting Juan Fernández Ridge, a hot spot seamount chain on the Nazca Plate. The complex tectonic setting makes this region an excellent laboratory to explore and quantify the relative contributions of thermal and compositional heterogeneities to the mantle discontinuity structure. In this study we combine data available from four past temporary experiments: 18 seismic stations from CHARGE; 43 from SIEMBRA, 12 from ESP and 30 from PUDEL. The research tools are the Pds phases (the direct P wave converted to an S wave while passing through a seismic discontinuity at depth d). These signals arrive in the coda of the P-phase in the radial component and are expected to be coherent with the waveform of the first arrival for conversion at discontinuities thinner than one half of the P-wavelength. In order to extract these converted phases by means of waveform similarity, we use the receiver function (RF) technique, i.e. the deconvolution of the vertical from the radial component in the frequency domain. The Pds phases are then detected on stacked RF (globally and by common conversion point) in the relative time-slowness domain. Since the incidence angle of converted phases is larger than the incidence angle of the P phase, they are expected with negative slowness. This permits to separate them from the multiples, which are instead expected with positive slowness. We measure amplitudes and arrival times for the

  19. 3D seismic structures in different subduction zones (Central Java, Toba Caldera, Central Chile, Costa-Rica and others): common and particular features

    NASA Astrophysics Data System (ADS)

    Koulakov, I.

    2009-12-01

    We present several seismic models for different subduction zones derived using the LOTOS tomographic code based on travel times from local earthquakes. The quality and reliability of all these models are supported by various tests (odd/even test, reconstructions with different starting models and free parameters, synthetic modeling with realistic setup, etc). For two datasets (Central Chile and Costa-Rica) we present the results of anisotropic inversion, which determines the orientations and values of fastest and slowest velocities in each point of the study volume. Comparing the velocity models for all considered subduction zones reveals some common features and differences. For example, in all cases we observe a clear low velocity anomaly which appears to link the cluster of intermediate seismicity in the Benioff zone with the volcanoes of the main arc. This pattern is interpreted as paths of ascending fluids and melts which are related to phase transitions in the slab. However, the depths of the seismicity clusters and dipping angle of the low-velocity anomaly are considerably different. For example, beneath Toba the cluster is at 100-130 km depth, and the anomaly is vertical. In Central Java the anomaly is strongly inclined to the direction of the slab, while beneath Central Chile it has the opposite orientation. The amplitudes of velocity anomalies are considerably different. The strongest heterogeneity (up to 30% of negative anomaly) is observed in the crust beneath Central Java, while much lower amplitudes (~15%) are found beneath the Toba Caldera, where a catastrophic super-eruption took place about 70000 years ago. The anisotropic inversion reveal similar features in Costa-Rica and Central Java: trench perpendicular fast velocity orientations in the subducting plate and trench parallel orientations in the mantle wedge. This is consistent with shear wave splitting results obtained for many other subduction zones. Such anisotropy in the corner flow may be

  20. Spatial and space-time clustering of tuberculosis in Gurage Zone, Southern Ethiopia.

    PubMed

    Tadesse, Sebsibe; Enqueselassie, Fikre; Hagos, Seifu

    2018-01-01

    Spatial targeting is advocated as an effective method that contributes for achieving tuberculosis control in high-burden countries. However, there is a paucity of studies clarifying the spatial nature of the disease in these countries. This study aims to identify the location, size and risk of purely spatial and space-time clusters for high occurrence of tuberculosis in Gurage Zone, Southern Ethiopia during 2007 to 2016. A total of 15,805 patient data that were retrieved from unit TB registers were included in the final analyses. The spatial and space-time cluster analyses were performed using the global Moran's I, Getis-Ord [Formula: see text] and Kulldorff's scan statistics. Eleven purely spatial and three space-time clusters were detected (P <0.001).The clusters were concentrated in border areas of the Gurage Zone. There were considerable spatial variations in the risk of tuberculosis by year during the study period. This study showed that tuberculosis clusters were mainly concentrated at border areas of the Gurage Zone during the study period, suggesting that there has been sustained transmission of the disease within these locations. The findings may help intensify the implementation of tuberculosis control activities in these locations. Further study is warranted to explore the roles of various ecological factors on the observed spatial distribution of tuberculosis.

  1. [First report of Montagnea arenaria (D.C.) Zeller (Agaricales) in Chile].

    PubMed

    Madrid Lorca, Hugo; Muñoz, Mélica

    2006-06-01

    Montagnea arenaria (D.C.) Zeller (Agaricales), an interesting basidiomycete adapted to arid environments is recorded for the first time from a sample collected on sandy soil in the northern zone of Chile. Its mature fruiting body is described. Taxonomic and ecological comments are also addressed.

  2. Experimental thermomechanical damage as first approach to understand the petrophysical behavior of the granitic host-rocks from an active fractured-geothermal system (Liquiñe, Chile - 39º S)

    NASA Astrophysics Data System (ADS)

    Molina Piernas, E.; Sepúlveda, J.; Arancibia, G.; Roquer, T.; Morata, D.; Bracke, R.; Vázquez, P.

    2017-12-01

    Chile's location along an active subduction zone has endowed it with a high geothermal potential. However, a better understanding of the thermomechanical and fluid transport properties of rocks is required to assess the potential of geothermal systems and thereby enhance the possibilities for their use. We have focused in the area surrounding Liquiñe, in the Southern Andean Volcanic Zone (Chile, 39º S). This area hosts several recent thermal manifestations, predominantly hot springs, and it is affected by the Liquiñe-Ofqui Fault Zone (LOFZ), which controls the position of the modern volcanic arc in southern Chile and cuts the Patagonian batholith. We have carried out experimental analyzes in order to understand this geothermal system and the influence of the thermomechanical features over the granitic host-rocks (low-porous crystalline rocks). To do this, physical properties such as capillary water absorption coefficient, Vp-wave velocity and compressive resistance were evaluated before and after heating rock samples at 150 ºC and 210 ºC (at ambient pressure) in an oven at a heating rate of 6 °C/min and maintaining the maximum temperature for 4 hours. The cooling rate was less than 2 °C/min to avoid shrinkage phenomena. The results show that the damage by heat was greater at 210 ºC than 150 ºC, likely due to an increased capillary coefficient ( 30% and 25%). On the contrary, Vpvelocity ( -19% and -13%) and compressive resistance ( -27% in both cases) decreased, with respect to unheated samples. Consequently, we can infer an inherent effect on the later fracture process due to the thermal stress when this granitic body was at depth. After that, and considering the local and regional strain-stress state, both factors have facilitated the fluid flow, increasing the permeability of this granitic host-rock allowing the presence of hot-springs. Future work will be to acquire complementary petrophysical parameters, such as porosity, permeability, thermal

  3. P-wave tomography of the Chile Triple Junction region

    NASA Astrophysics Data System (ADS)

    Miller, M. R.; Priestley, K. F.; Tilmann, F. J.; Iwamori, H.; Bataille, K.

    2010-12-01

    We investigate the crustal and upper mantle structure of the Aysén region of Chile. This region is situated from 44 to 49oS, a place where the diverging oceanic Nazca and Antarctic plates subduct beneath the South American continent. The Seismic Experiment in the Aysén Region of CHile (SEARCH) project operated a network of up to 60 land-based seismometers in this region between 2004 and 2006, centred over a 6 Ma subducted spreading centre between the oceanic plates. The data is used to examine the P-wave velocity structure beneath the region using relative-arrival teleseismic travel time tomography, using 2534 P-wave residuals from 173 teleseismic earthquakes. It is possible to image the velocity structure beneath the seismic network down to ˜300 km depth. The velocity structure has a maximum resolution of ˜60 km and shows a large difference between the northern and southern parts of the region. To the north, a ˜100 km thick fast anomaly exists which dips away from the subduction trench; this is likely to be related to the subducting Nazca plate. Going to the south, as the age of this plate at the subduction trench decreases, the fast anomaly migrates further from the trench suggesting that the Nazca plate subducts at a low angle over a larger distance before the subduction angle steepens and hence slab tears exist across the fracture zones between parts of the slab of different age. Where the 6 Ma subducted ridge segment is predicted to lie there is a region of lower velocities between ˜200 and ˜100 km depth, and no fast region associated with a subducting slab is present. Instead, the lower velocities indicate the presence of an asthenospheric window between the subducted Nazca and Antarctic plate.

  4. Effects of Southern Hemispheric Wind Changes on Global Oxygen and the Pacific Oxygen Minimum Zone

    NASA Astrophysics Data System (ADS)

    Getzlaff, J.; Dietze, H.; Oschlies, A.

    2016-02-01

    We use a coupled ocean biogeochemistry-circulation model to compare the impact of changes in southern hemispheric winds with that of warming induced buoyancy fluxes on dissolved oxygen. Changes in the southern hemispheric wind fields, which are in line with an observed shift of the southern annual mode, are a combination of a strengthening and poleward shift of the southern westerlies. We differentiate between effects caused by a strengthening of the westerlies and effects of a southward shift of the westerlies that is accompanied by a poleward expansion of the tropical trade winds. Our results confirm that the Southern Ocean plays an important role for the marine oxygen supply: a strengthening of the southern westerlies, that leads to an increase of the water formation rates of the oxygen rich deep and intermediate water masses, can counteract part of the warming-induced decline in marine oxygen levels. The wind driven intensification of the Southern Ocean meridional overturning circulation drives an increase of the global oxygen supply. Furthermore the results show that the shift of the boundary between westerlies and trades results in an increase of subantarctic mode water and an anti-correlated decrease of deep water formation and reduces the oceanic oxygen supply. In addition we find that the increased meridional extension of the southern trade winds, results in a strengthening and southward shift of the subtropical wind stress curl. This alters the subtropical gyre circulation (intensification and southward shift) and with it decreases the water mass transport into the oxygen minimum zone. In a business-as-usual CO2 emission scenario, the poleward shift of the trade-to-westerlies boundary is as important for the future evolution of the suboxic volume as direct warming-induced changes.

  5. Use of high-resolution satellite images for detection of geological structures related to Central Andes geothermal field, Chile.

    NASA Astrophysics Data System (ADS)

    Benavides-Rivas, C. L.; Soto-Pinto, C. A.; Arellano-Baeza, A. A.

    2014-12-01

    Central valley and the border with Argentina in the center, and in the fault system Liquiñe-Ofqui in the South of the country. High resolution images from the LANDSAT 8 satellite have been used to delineate the geological structures related to the potential geothermal reservoirs located at the northern end of the Southern Volcanic Zone of Chile. It was done by applying the lineament extraction technique, using the ADALGEO software, developed by [Soto et al., 2013]. These structures have been compared with the distribution of main geological structures obtained in the field. It was found that the lineament density increases in the areas of the major heat flux indicating that the lineament analysis could be a power tool for the detection of faults and joint zones associated to the geothermal fields. A lineament is generally defined as a straight or slightly curved feature in the landscape visible satellite image as an aligned sequence of pixel intensity contrast compared to the background. The system features extracted from satellite images is not identical to the geological lineaments that are generally determined by ground surveys, however, generally reflects the structure of faults and fractures in the crust. A temporal sequence of eight Landsat multispectral images of Central Andes geothermal field, located in VI region de Chile, was used to study changes in the configuration of the lineaments during 2011. The presence of minerals with silicification, epidotization, and albitization, which are typical for geothrmal reservoirs, was also identified, using their spectral characteristics, and subsequently corroborated in the field. Both lineament analysis and spectral analysis gave similar location of the reservoir, which increases reliability of the results.

  6. Fault-controlled permeability and fluid flow in low-porosity crystalline rocks: an example from naturally fractured geothermal systems in the Southern Andes

    NASA Astrophysics Data System (ADS)

    Arancibia, G.; Roquer, T.; Sepúlveda, J.; Veloso, E. A.; Morata, D.; Rowland, J. V.

    2017-12-01

    Fault zones can control the location, emplacement, and evolution of economic mineral deposits and geothermal systems by acting as barriers and/or conduits to crustal fluid flow (e.g. magma, gas, oil, hydro-geothermal and groundwater). The nature of the fault control permeability is critical in the case of fluid flow into low porosity/permeability crystalline rocks, since structural permeability provides the main hydraulic conductivity to generate a natural fractured system. However, several processes accompanying the failure of rocks (i.e. episodic permeability given by cycling ruptures, mineral precipitation from fluids in veins, dissolution of minerals in the vicinity of a fracture) promote a complex time-dependent and enhancing/reducing fault-controlled permeability. We propose the Southern Volcanic Zone (Southern Andes, Chile) as a case study to evaluate the role of the structural permeability in low porosity crystalline rocks belonging to the Miocene North Patagonian Batholith. Recently published studies propose a relatively well-constrained first-order role of two active fault systems, the arc-parallel (NS to NNE trending) Liquiñe Ofqui Fault System and the arc-oblique (NW trending) Andean Transverse Fault Zones, in fluid flow at crustal scales. We now propose to examine the Liquiñe ( 39°S) and Maihue ( 40°S) areas as sites of interaction between these fault systems, in order to evaluate a naturally fractured geothermal system. Preliminary results indicate upwelling of thermal water directly from fractured granite or from fluvial deposits overlying granitoids. Measured temperatures of thermal springs suggest a low- to medium-enthalpy system, which could potentially be harnessed for use in geothermal energy applications (e.g. heating, wood dryer and green house), which are much needed in Southern Chile. Future work will aim to examine the nature of structural permeability from the regional to the microscopic scale connecting the paleo- and current- fluid

  7. Detrital Geochemical Fingerprints of Rivers Along Southern Tibet and Nepal: Implications for Erosion of the Indus-Yarlung Suture Zone and the Himalayas

    NASA Astrophysics Data System (ADS)

    Hassim, M. F. B.; Carrapa, B.; DeCelles, P. G.; Kapp, P. A.; Gehrels, G. E.

    2014-12-01

    Our detrital geochemical study of modern sand collected from tributaries of the Yarlung River in southern Tibet and the Kali Gandaki River and its tributaries in Nepal shed light on the ages and exhumation histories of source rocks within the Indus-Yarlung Suture (IYS) zone and the Himalayas. Seven sand samples from rivers along the suture zone in southern Tibet between Xigatze to the east and Mt. Kailas to the west were collected for detrital zircon U-Pb geochronologic and Apatite Fission Track (AFT) thermochronologic analyses. Zircon U-Pb ages for all rivers range between 15 and 3568 Ma. Rivers draining the northern side of the suture zone mainly yield ages between 40 and 60 Ma, similar to the age of the Gangdese magmatic arc. Samples from rivers draining the southern side of the suture zone record a Tethyan Himalayan signal characterized by age clusters at 500 Ma and 1050 Ma. Our results indicate that the ages and proportion of U-Pb zircons ages of downstream samples from tributaries of the Yarlung River directly reflect source area ages and relative area of source rock exposure in the catchment basin. Significant age components at 37 - 40 Ma, 47 - 50 Ma, 55 - 58 Ma and 94 - 97 Ma reflect episodicity in Gangdese arc magmatism. Our AFT ages show two main signals at 23-18 Ma and 12 Ma, which are in agreement with accelerated exhumation of the Gangdese batholith during these time intervals. The 23 - 18 Ma signal partly overlaps with deposition of the Kailas Formation along the suture zone and may be related to exhumation due to upper plate extension in southern Tibet in response to Indian slab rollback and/or break-off events. Detrital thermochronology of four sand samples from the Kali Gandaki River and some of its tributaries in Nepal is underway and will provide constraints on the timing of erosion of the central Nepal Himalaya.

  8. Multiple melt bodies fed the AD 2011 eruption of Puyehue-Cordón Caulle, Chile.

    PubMed

    Alloway, B V; Pearce, N J G; Villarosa, G; Outes, V; Moreno, P I

    2015-12-02

    Within the volcanological community there is a growing awareness that many large- to small-scale, point-source eruptive events can be fed by multiple melt bodies rather than from a single magma reservoir. In this study, glass shard major- and trace-element compositions were determined from tephra systematically sampled from the outset of the Puyehue-Cordón Caulle (PCC) eruption (~1 km(3)) in southern Chile which commenced on June 4(th), 2011. Three distinct but cogenetic magma bodies were simultaneously tapped during the paroxysmal phase of this eruption. These are readily identified by clear compositional gaps in CaO, and by Sr/Zr and Sr/Y ratios, resulting from dominantly plagioclase extraction at slightly different pressures, with incompatible elements controlled by zircon crystallisation. Our results clearly demonstrate the utility of glass shard major- and trace-element data in defining the contribution of multiple magma bodies to an explosive eruption. The complex spatial association of the PCC fissure zone with the Liquiñe-Ofqui Fault zone was likely an influential factor that impeded the ascent of the parent magma and allowed the formation of discrete melt bodies within the sub-volcanic system that continued to independently fractionate.

  9. Preliminary data on polybrominated diphenyl ethers (PBDEs) in farmed fish tissues (Salmo salar) and fish feed in Southern Chile.

    PubMed

    Montory, Mónica; Barra, Ricardo

    2006-05-01

    Polybrominated diphenyl ethers (PBDEs) have become an issue of global concern. Recent studies have shown that farmed salmon can accumulate high levels of brominated compounds in their tissues and consequently there is a growing concern on its industrial and public health impacts. Little information is found in the international literature on PBDEs in the biotic compartment of the Southern Hemisphere. This paper reports the levels of several PBDE congeners found in the tissues of farmed fish from five different farming areas of Southern Chile. PBDEs were analyzed by HRGC-MS. More analytical data were obtained by analyzing these same pollutants in fish feed. Our results indicate a general trend of PBDE levels averaging 1.46 ng g(-1) wet weight (wwt). The observed congeneric distribution that resulted was quite similar to data previously reported in the open literature. PBDE profiles were found to be dominated by BDE 47. No correlation was observed between levels found in the tissues and the lipid content in such tissues, although a high correlation with the fish feed data was observed indicating that this could probably be the main PDBE entry source into fish, although other sources cannot be excluded. Even though the samples were obtained from different geographical areas, they presented fairly similar profiles, indicating a potential common source. We concluded that PBDE levels in the farmed Chilean salmon are in the low average range of values published in the open literature.

  10. Foreshock patterns preceding large earthquakes in the subduction zone of Chile

    NASA Astrophysics Data System (ADS)

    Minadakis, George; Papadopoulos, Gerassimos A.

    2016-04-01

    Some of the largest earthquakes in the globe occur in the subduction zone of Chile. Therefore, it is of particular interest to investigate foreshock patterns preceding such earthquakes. Foreshocks in Chile were recognized as early as 1960. In fact, the giant (Mw9.5) earthquake of 22 May 1960, which was the largest ever instrumentally recorded, was preceded by 45 foreshocks in a time period of 33h before the mainshock, while 250 aftershocks were recorded in a 33h time period after the mainshock. Four foreshocks were bigger than magnitude 7.0, including a magnitude 7.9 on May 21 that caused severe damage in the Concepcion area. More recently, Brodsky and Lay (2014) and Bedford et al. (2015) reported on foreshock activity before the 1 April 2014 large earthquake (Mw8.2). However, 3-D foreshock patterns in space, time and size were not studied in depth so far. Since such studies require for good seismic catalogues to be available, we have investigated 3-D foreshock patterns only before the recent, very large mainshocks occurring on 27 February 2010 (Mw 8.8), 1 April 2014 (Mw8.2) and 16 September 2015 (Mw8.4). Although our analysis does not depend on a priori definition of short-term foreshocks, our interest focuses in the short-term time frame, that is in the last 5-6 months before the mainshock. The analysis of the 2014 event showed an excellent foreshock sequence consisting by an early-weak foreshock stage lasting for about 1.8 months and by a main-strong precursory foreshock stage that was evolved in the last 18 days before the mainshock. During the strong foreshock period the seismicity concentrated around the mainshock epicenter in a critical area of about 65 km mainly along the trench domain to the south of the mainshock epicenter. At the same time, the activity rate increased dramatically, the b-value dropped and the mean magnitude increased significantly, while the level of seismic energy released also increased. In view of these highly significant seismicity

  11. Climate change impacts on municipal, mining, and agricultural water supplies in Chile

    Treesearch

    Daniel G. Neary; Pablo Garcia-Chevesich

    2008-01-01

    Agricultural and municipal water supply interests in Chile rely heavily on streams which flow from the Andes Mountains. The highly productive Copiapo agricultural region, on the southern edge of the Atacama Desert, is a major supplier of fruit and other crops for the Northern American market during winter. This region relies entirely on snow and icemelt streams to...

  12. Simulated effects of southern hemispheric wind changes on the Pacific oxygen minimum zone

    NASA Astrophysics Data System (ADS)

    Getzlaff, Julia; Dietze, Heiner; Oschlies, Andreas

    2016-01-01

    A coupled ocean biogeochemistry-circulation model is used to investigate the impact of observed past and anticipated future wind changes in the Southern Hemisphere on the oxygen minimum zone in the tropical Pacific. We consider the industrial period until the end of the 21st century and distinguish effects due to a strengthening of the westerlies from effects of a southward shift of the westerlies that is accompanied by a poleward expansion of the tropical trade winds. Our model results show that a strengthening of the westerlies counteracts part of the warming-induced decline in the global marine oxygen inventory. A poleward shift of the trade-westerlies boundary, however, triggers a significant decrease of oxygen in the tropical oxygen minimum zone. In a business-as-usual CO2 emission scenario, the poleward shift of the trade-westerlies boundary and warming-induced increase in stratification contribute equally to the expansion of suboxic waters in the tropical Pacific.

  13. The Varve Record of Puyehue Lake (Meridional Chile), AD 1412-2002 .

    NASA Astrophysics Data System (ADS)

    Boes, X.; Arnaud, F.; Fagel, N.

    2004-12-01

    Puyehue Lake is located in the Southern Volcanic Zone of Chile (Southern Lake District, 40°S). This monomictic lake is under the influence of the oceanic winter polar front (WPF) and constitutes a powerful sedimentary archive for paleoenvironmental reconstruction. The underflow (PUI) and interflow (PUII) coring sites were selected by a high resolution seismic survey (RUG). The sedimentation is driven by the annual blooms of diatoms in association with thermal lake cycles. For each site, one short core (50-60 cm) is analyzed by continuous cover of thin sections for varve counting and chronology for the AD 1412-2002 time window. The varve chronology is constrained by 210Pb,137Cs sedimentation rate estimates, and by the AD 1960 Valdivia'seismite. The sediment laminations are especially emphasized by the continuous grey-scale measurements from thin sections. Detrital clayey material characterizes the dark levels, and biogenic diatom mud defines the light levels. Varve counting is derived from the occurrence of light layers, i.e. formed at the end of winter after nutrient turn-over. In both cores, the grey-scale is influenced by instantaneous tephra layers related to the regional volcanic activity (Puyehue and Cordon Caulle volcanoes). For instance, in PUII, we identify major historical eruptions (AD 1921, 1837, 1790, 1564, and 1544) in accordance with the varve age model. In addition, we measure the total varve thickness. Lower than 500 µm until AD 1780, the varve thickness gradually increases by a factor of four in PUII. The first period suggests a decrease of lake productivity, in agreement with a cooling. The age fits with the end of Little Ice Age in Southern America. Between AD 1780-2002, the thicker varves could be driven by a reinforcement of the WPF since the 19e century. Our local observations require further investigations to be extrapolated over regional or global scale.

  14. Three new species of Neofidelia (Hymenoptera: Apoidea: Megachilidae) from Northern Chile.

    PubMed

    Dumesh, Sheila; Packer, Laurence

    2013-02-01

    Neofidelia apacheta Dumesh and Packer, sp. nov., N. camanchaca Dumesh and Packer, sp. nov., and N. submersa Dumesh and Packer, sp. nov. are described from northern Chile. Neofidelia apacheta is known from large numbers of specimens and localities at moderately high elevation (1600-3200m). Neofidelia camanchaca is only known from the ho-lotype male. Neofidelia submersa is known from the holotype male and a pair of paratypes in poor condition, all from a coastal fog oasis. Comparisons are made with the two previously described species of the genus. The collection of N. apa-cheta from so far north in Chile suggests that Neofidelia is likely to be found in southern Peru. A key for the five species of the genus is provided.

  15. 33 CFR 100.1101 - Southern California annual marine events for the San Diego Captain of the Port Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... events for the San Diego Captain of the Port Zone. 100.1101 Section 100.1101 Navigation and Navigable... NAVIGABLE WATERS § 100.1101 Southern California annual marine events for the San Diego Captain of the Port... 83] 1. San Diego Fall Classic Sponsor San Diego Rowing Club. Event Description Competitive rowing...

  16. 33 CFR 100.1101 - Southern California annual marine events for the San Diego Captain of the Port Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... events for the San Diego Captain of the Port Zone. 100.1101 Section 100.1101 Navigation and Navigable... NAVIGABLE WATERS § 100.1101 Southern California annual marine events for the San Diego Captain of the Port... 83] 1. San Diego Fall Classic Sponsor San Diego Rowing Club. Event Description Competitive rowing...

  17. Deterministic seismogenic scenarios based on asperities spatial distribution to assess tsunami hazard on northern Chile (18°S to 24°S)

    NASA Astrophysics Data System (ADS)

    González-Carrasco, J. F.

    2016-12-01

    Southern Peru and northern Chile coastal areas, extended between 12º to 24ºS, have been recognized as a mature seismic gap with a high seismogenic potential associated to seismic moment deficit accumulated since 1877. An important scientific question is which will be the breaking pattern of a future megathrust earthquake, being relevant from hazard assessment perspective. During the last decade, the occurrence of three major subduction earthquakes has given the possibility to acquire outstanding geophysical and geological information to know the behavior of phenomena. An interesting result is the relationship between the maximum slip areas and the spatial distribution of asperities in subduction zones. In this contribution, we propose a methodology to identify a regional pattern of main asperities to construct reliable seismogenic scenarios in a seismic gap. We follow a deterministic approach to explore the distribution of asperities segmentation using geophysical and geodetic data as trench-parallel gravity anomaly (TPGA), interseismic coupling (ISC), b-value, historical moment release, residual bathymetric and gravity anomalies. The combined information represents physical constraints for short and long term suitable regions for future mega earthquakes. To illuminate the asperities distribution, we construct profiles using fault coordinates, along-strike and down-dip direction, of all proxies to define the boundaries of a major asperities (> 100 km). The geometry of a major asperity is useful to define a finite set of future deterministic seismogenic scenarios to evaluate tsunamigenic hazard in main cities of northern zone of Chile (18°S to 24°S).

  18. Ammonia-oxidizing beta-proteobacteria from the oxygen minimum zone off northern Chile.

    PubMed

    Molina, Verónica; Ulloa, Osvaldo; Farías, Laura; Urrutia, Homero; Ramírez, Salvador; Junier, Pilar; Witzel, Karl-Paul

    2007-06-01

    The composition of ammonia-oxidizing bacteria from the beta-Proteobacteria subclass (betaAOB) was studied in the surface and upper-oxycline oxic waters (2- to 50-m depth, approximately 200 to 44 microM O(2)) and within the oxygen minimum zone (OMZ) suboxic waters (50- to 400-m depth, < or =10 microM O(2)) of the eastern South Pacific off northern Chile. This study was carried out through cloning and sequencing of genes coding for 16S rRNA and the ammonia monooxygenase enzyme active subunit (amoA). Sequences affiliated with Nitrosospira-like cluster 1 dominated the 16S rRNA gene clone libraries constructed from both oxic and suboxic waters. Cluster 1 consists exclusively of yet-uncultivated betaAOB from marine environments. However, a single clone, out of 224 obtained from the OMZ, was found to belong to Nitrosospira lineage cluster 0. To our knowledge, cluster 0 sequences have been derived from betaAOB isolated only from sand, soil, and freshwater environments. Sequences in clone libraries of the amoA gene from the surface and upper oxycline could be grouped in a marine subcluster, also containing no cultured representatives. In contrast, all 74 amoA sequences originating from the OMZ were either closely affiliated with cultured Nitrosospira spp. from clusters 0 and 2 or with other yet-uncultured betaAOB from soil and an aerated-anoxic Orbal process waste treatment plant. Our results reveal the presence of Nitrosospira-like betaAOB in both oxic and suboxic waters associated with the OMZ but with a clear community shift at the functional level (amoA) along the strong oxygen gradient.

  19. Gradual unlocking of a plate boundary controlled the April 2014 M8.1 Iquique, Northern Chile megathrust earthquake

    NASA Astrophysics Data System (ADS)

    Schurr, B.; Hainzl, S.; Bedford, J. R.; Hoechner, A.; Wang, R.; Zhang, Y.; Oncken, O.; Palo, M.; Bartsch, M.; Moreno, M.; Tilmann, F. J.; Dahm, T.; Victor, P.; Barrientos, S. E.; Vilotte, J. P.

    2014-12-01

    On April 1st, 2014, Northern Chile, was struck by a magnitude 8.1 earthquake near the city of Iquique following a protracted series of foreshocks. The earthquake occurred within a seismic gap left behind by two great earthquakes devastating the northern Chilean and southern Peruvian coast about 140 years ago in 1868 and 1877. This segment, about 500 km long, was the only one along the Chilean subduction zone that has not ruptured within the last century. The Integrated Plate boundary Observatory Chile (IPOC) monitored the entire sequence of events, providing unprecedented resolution of the build-up to the main event and its rupture evolution. We analyzed the entire seismicity in this section of the subduction zone since 2007. The offshore rupture region of the Iquique event has been more or less continuously seismically active within our observation period. This is in contrast to the segments to the north and south, which are still unruptured and seismically quiet. Starting in July 2013, three foreshock clusters with increasingly larger magnitudes occurred within the future rupture area. The largest Mw 6.7 foreshock, two weeks before the mainshock, had a source mechanism distinctively different from the mainshock and with a centroid depth of only 9 km probably occurred in the upper plate. The Iquique mainshock initiated then at the northern end of the foreshock zone, inside a region of intermediate interseismic locking. Comparing the foreshock distribution to the long term deformation history of the margin, we find that the area exhibits a high gradient of locking from weakly locked updip to fully locked downdip. Mapping the b-value of the foreshocks indicates significantly lower b-values in the source area compared to all other regions where the b-value can be resolved. Importantly, a gradual drop of the b-value from about 0.75 to below 0.6 is observed in the source region within the three years before the Iquique earthquake. This has only been reversed within the

  20. A diverse assemblage of fossil hardwood from the Upper Tertiary (Miocene?) of the Arauco Peninsula, Chile

    NASA Astrophysics Data System (ADS)

    Schöning, Meike; Bandel, Klaus

    2004-09-01

    Silicified woods of 10 dicotyledonous tree families of probably Miocene age from the Arauco Peninsula, central Chile are described and classified according to their anatomy. The diversity is surprisingly high, in that of the 19 samples analyzed, virtually every one could belong to a different species of tree or shrub. Almost all species document a damp climate, and most have related species living in the central zone of modern Chile. The samples were collected in a narrow zone on Punta El Fraile, west of the town of Arauco. The following families are based on woods from the Arauco Peninsula: Anacardiaceae, Boraginaceae, Euphorbiaceae, Fagaceae, Lauraceae, Leguminosae, Monimiaceae, the first report of fossil Myristicaceae, Myrtaceae, and Proteaceae. Their diagenetic history is connected to tuffaceous material and calcareous concretions.

  1. Integrated Geophysical Characteristics of the 2015 Illapel, Chile, Earthquake

    NASA Astrophysics Data System (ADS)

    Herman, M. W.; Yeck, W. L.; Nealy, J. L.; Hayes, G. P.; Barnhart, W. D.; Benz, H.; Furlong, K. P.

    2015-12-01

    On September 16th, 2015, an Mw 8.3 earthquake (USGS moment magnitude) ruptured offshore of central Chile, 50 km west of the city of Illapel and 200 km north of Santiago. The earthquake occurred just north of where the Juan Fernandez Ridge enters the subduction zone. In this study, we integrate multiple seismic and geodetic datasets, including multiple-event earthquake relocations; moment tensors of the Illapel mainshock, aftershocks, and prior regional seismicity; finite fault models (FFMs) of the mainshock rupture; subduction zone geometry; Coulomb stress transfer calculations; and co-seismic GPS offsets and InSAR images. These datasets allow us to (a) assess the context of the Illapel earthquake sequence with respect to historical seismicity in central Chile; (b) constrain the relationship between subduction geometry and the kinematic characteristics of the earthquake sequence; and (c) understand the distribution of aftershocks with respect to the rupture zone. Double source W-phase moment tensor analysis indicates the Illapel mainshock rupture began as a smaller Mw ~7.2 thrusting event before growing into a great-sized Mw 8.3 earthquake. Relocated aftershock seismicity is concentrated around the main region of slip, and few aftershocks occur on the megathrust shallower than ~15 km, despite the FFM indicating slip near the trench. This distribution is consistent with the aftershock behavior following the 2010 Maule and 2014 Iquique earthquakes: aftershocks primarily surround the rupture zones and are largely absent from regions of greatest slip. However, in contrast to the recent 2014 Iquique and 2010 Maule events, which ruptured in regions of the Chilean subduction zone that had not had large events in over a century, this earthquake occurred in a section of the subduction zone that hosted a large earthquake as recently as 1943, as well as earlier significant events in 1880 and 1822. At this section of the subduction zone, in addition to the impinging Juan

  2. The seasonal sea-ice zone in the glacial Southern Ocean as a carbon sink.

    PubMed

    Abelmann, Andrea; Gersonde, Rainer; Knorr, Gregor; Zhang, Xu; Chapligin, Bernhard; Maier, Edith; Esper, Oliver; Friedrichsen, Hans; Lohmann, Gerrit; Meyer, Hanno; Tiedemann, Ralf

    2015-09-18

    Reduced surface-deep ocean exchange and enhanced nutrient consumption by phytoplankton in the Southern Ocean have been linked to lower glacial atmospheric CO2. However, identification of the biological and physical conditions involved and the related processes remains incomplete. Here we specify Southern Ocean surface-subsurface contrasts using a new tool, the combined oxygen and silicon isotope measurement of diatom and radiolarian opal, in combination with numerical simulations. Our data do not indicate a permanent glacial halocline related to melt water from icebergs. Corroborated by numerical simulations, we find that glacial surface stratification was variable and linked to seasonal sea-ice changes. During glacial spring-summer, the mixed layer was relatively shallow, while deeper mixing occurred during fall-winter, allowing for surface-ocean refueling with nutrients from the deep reservoir, which was potentially richer in nutrients than today. This generated specific carbon and opal export regimes turning the glacial seasonal sea-ice zone into a carbon sink.

  3. The seasonal sea-ice zone in the glacial Southern Ocean as a carbon sink

    PubMed Central

    Abelmann, Andrea; Gersonde, Rainer; Knorr, Gregor; Zhang, Xu; Chapligin, Bernhard; Maier, Edith; Esper, Oliver; Friedrichsen, Hans; Lohmann, Gerrit; Meyer, Hanno; Tiedemann, Ralf

    2015-01-01

    Reduced surface–deep ocean exchange and enhanced nutrient consumption by phytoplankton in the Southern Ocean have been linked to lower glacial atmospheric CO2. However, identification of the biological and physical conditions involved and the related processes remains incomplete. Here we specify Southern Ocean surface–subsurface contrasts using a new tool, the combined oxygen and silicon isotope measurement of diatom and radiolarian opal, in combination with numerical simulations. Our data do not indicate a permanent glacial halocline related to melt water from icebergs. Corroborated by numerical simulations, we find that glacial surface stratification was variable and linked to seasonal sea-ice changes. During glacial spring–summer, the mixed layer was relatively shallow, while deeper mixing occurred during fall–winter, allowing for surface-ocean refueling with nutrients from the deep reservoir, which was potentially richer in nutrients than today. This generated specific carbon and opal export regimes turning the glacial seasonal sea-ice zone into a carbon sink. PMID:26382319

  4. Variations of the aerosol concentration and chemical composition over the arid steppe zone of Southern Russia in summer

    NASA Astrophysics Data System (ADS)

    Artamonova, M. S.; Gubanova, D. P.; Iordanskii, M. A.; Lebedev, V. A.; Maksimenkov, L. O.; Minashkin, V. M.; Obvintsev, Y. I.; Chketiani, O. G.

    2016-12-01

    Variations in the surface aerosol over the arid steppe zone of Southern Russia have been measured. The parameters of atmospheric aerosol (mass concentration, both dispersed and elemental compositions) and meteorological parameters were measured in Tsimlaynsk raion (Rostov oblast). The chemical composition of aerosol particles in the atmospheric surface layer has been determined, and the coefficients of enrichment of elements with respect to clarkes in the Earth's crust have been calculated. It is shown that, in summer, arid aerosols are transported from both alkaline and sandy soils of Kalmykia to the air basin over the observation zone. Aerosol particles in the surface air layer over this region have been found to contain the products of combustion of oil, coal, and ethylized fuel. These combustion products make a small contribution to the total mass concentration of atmospheric aerosol; however, they are most hazardous to the health of people because of their sizes and heavy-metal contents. A high concentration of submicron sulfur-containing aerosol particles of chemocondensation nature has been recorded. Sources of aerosol of both natural and anthropogenic origins in southern Russia are discussed.

  5. Two new species of the Liolaemuselongatus-kriegi complex (Iguania, Liolaemidae) from Andean highlands of southern Chile.

    PubMed

    Troncoso-Palacios, Jaime; Díaz, Hugo A; Esquerré, Damien; Urra, Felix A

    2015-01-01

    The elongatus-kriegi complex is one of the most diverse clades of the Liolaemus (sensu stricto) subgenus of lizards. There are currently 29 species recognized in this group distributed between Chile and Argentina. Based on molecular evidence, there seem to be five main clades nested within this complex: the elongatus, leopardinus, kriegi, petrophilus and punmahuida clades. Liolaemusbuergeri and Liolaemuskriegi, both of the kriegi clade, were believed to inhabit the surroundings of the Laja Lagoon, in the Biobío Region of Chile. Moreover, this Chilean population of Liolaemuskriegi was recently recognized as an undescribed taxon called "Liolaemus sp. A" based on molecular phylogenetics. In this work, we studied these two populations of the Laja Lagoon and provided the morphological diagnosis to describe them as two new species: Liolaemusscorialis sp. n. and Liolaemuszabalai sp. n., previously considered Liolaemusbuergeri and "Liolaemuskriegi/Liolaemus sp. A" respectively. Additionally, we identified another population of Liolaemusscorialis in the vicinity of La Mula Lagoon in the Araucanía Region of Chile. Liolaemusscorialis differs from almost all of the species of the elongatus-kriegi complex by its considerably smaller size. Nevertheless, without molecular data we cannot assign it to any particular subclade. Liolaemuszabalai belongs to the kriegi clade based on published molecular phylogenies. Finally, we provide some natural history data on both species and we document for the first time the presence of Liolaemusneuquensis in Chile from a museum specimen from La Mula Lagoon.

  6. Late Quaternary strike-slip along the Taohuala Shan-Ayouqi fault zone and its tectonic implications in the Hexi Corridor and the southern Gobi Alashan, China

    NASA Astrophysics Data System (ADS)

    Yu, Jing-xing; Zheng, Wen-jun; Zhang, Pei-zhen; Lei, Qi-yun; Wang, Xu-long; Wang, Wei-tao; Li, Xin-nan; Zhang, Ning

    2017-11-01

    The Hexi Corridor and the southern Gobi Alashan are composed of discontinuous a set of active faults with various strikes and slip motions that are located to the north of the northern Tibetan Plateau. Despite growing understanding of the geometry and kinematics of these active faults, the late Quaternary deformation pattern in the Hexi Corridor and the southern Gobi Alashan remains controversial. The active E-W trending Taohuala Shan-Ayouqi fault zone is located in the southern Gobi Alashan. Study of the geometry and nature of slip along this fault zone holds crucial value for better understanding the regional deformation pattern. Field investigations combined with high-resolution imagery show that the Taohuala Shan fault and the E-W trending faults within the Ayouqi fault zone (F2 and F5) are left-lateral strike-slip faults, whereas the NW or WNW-trending faults within the Ayouqi fault zone (F1 and F3) are reverse faults. We collected Optically Stimulated Luminescence (OSL) and cosmogenic exposure age dating samples from offset alluvial fan surfaces, and estimated a vertical slip rate of 0.1-0.3 mm/yr, and a strike-slip rate of 0.14-0.93 mm/yr for the Taohuala Shan fault. Strata revealed in a trench excavated across the major fault (F5) in the Ayouqi fault zone and OSL dating results indicate that the most recent earthquake occurred between ca. 11.05 ± 0.52 ka and ca. 4.06 ± 0.29 ka. The geometry and kinematics of the Taohuala Shan-Ayouqi fault zone enable us to build a deformation pattern for the entire Hexi Corridor and the southern Gobi Alashan, which suggest that this region experiences northeastward oblique extrusion of the northern Tibetan Plateau. These left-lateral strike-slip faults in the region are driven by oblique compression but not associated with the northeastward extension of the Altyn Tagh fault.

  7. Rapid uplift in Laguna del Maule volcanic field of the Andean Southern Volcanic Zone (Chile) measured by satellite radar interferometry

    NASA Astrophysics Data System (ADS)

    Feigl, K.; Ali, T.; Singer, B. S.; Pesicek, J. D.; Thurber, C. H.; Jicha, B. R.; Lara, L. E.; Hildreth, E. W.; Fierstein, J.; Williams-Jones, G.; Unsworth, M. J.; Keranen, K. M.

    2011-12-01

    The Laguna del Maule (LdM) volcanic field of the Andean Southern Volcanic Zone extends over 500 square kilometers and comprises more than 130 individual vents. As described by Hildreth et al. (2010), the history has been defined from sixty-eight Ar/Ar and K-Ar dates. Silicic eruptions have occurred throughout the past 3.7 Ma, including welded ignimbrite associated with caldera formation at 950 ka, small rhyolitic eruptions between 336 and 38 ka, and a culminating ring of 36 post-glacial rhyodacite and rhyolite coulees and domes that encircle the lake. Dating of five post-glacial flows implies that these silicic eruptions occurred within the last 25 kyr. Field relations indicate that initial eruptions comprised modest volumes of mafic rhyodacite magma that were followed by larger volumes of high silica rhyolite. The post-glacial flare-up of silicic magmatism from vents distributed around the lake, is unprecedented in the history of this volcanic field. Using satellite radar interferometry (InSAR), Fournier et al. (2010) measured uplift at a rate of more than 180 mm/year between 2007 and 2008 in a round pattern centered on the west side of LdM. More recent InSAR observations suggest that rapid uplift has continued from 2008 through early 2011. In contrast, Fournier et al. found no measurable deformation in an interferogram spanning 2003 through 2004. In this study, we model the deformation field using the General Inversion of Phase Technique (GIPhT), as described by Feigl and Thurber (2009). Two different models fit the data. The first model assumes a sill at ~5 km depth has been inflating at a rate of more than 20 million cubic meters per year since 2007. The second model assumes that the water level in the lake dropped at a rate of 20 m/yr from January 2007 through February 2010, thus reducing the load on an elastic simulation of the crust. The rate of intrusion inferred from InSAR is an order of magnitude higher than the average rate derived from well-dated arc

  8. The Quaternary calc-alkaline volcanism of the Patagonian Andes close to the Chile triple junction: geochemistry and petrogenesis of volcanic rocks from the Cay and Maca volcanoes (˜45°S, Chile)

    NASA Astrophysics Data System (ADS)

    D'Orazio, M.; Innocenti, F.; Manetti, P.; Tamponi, M.; Tonarini, S.; González-Ferrán, O.; Lahsen, A.; Omarini, R.

    2003-08-01

    Major- and trace-element, Sr-Nd isotopes, and mineral chemistry data were obtained for a collection of volcanic rock samples erupted by the Cay and Maca Quaternary volcanoes, Patagonian Andes (˜45°S, Chile). Cay and Maca are two large, adjacent stratovolcanoes that rise from the Chiloe block at the southern end of the southern volcanic zone (SVZ) of the Andes. Samples from the two volcanoes are typical medium-K, calc-alkaline rocks that form two roughly continuous, largely overlapping series from subalkaline basalt to dacite. The overall geochemistry of the samples studied is very similar to that observed for most volcanoes from the southern SVZ. The narrow range of Sr-Nd isotope compositions ( 87Sr/ 86Sr=0.70389-0.70431 and 143Nd/ 144Nd=0.51277-0.51284) and the major- and trace-element distributions indicate that the Cay and Maca magmas differentiated by crystal fractionation without significant contribution by crustal contamination. This is in accordance with the thin (<30 km), relatively young (Paleozoic or more recent) continental crust beneath the volcanoes. The nature of the subduction-derived materials involved in the genesis of the Cay and Maca magmas is investigated by means of the relative concentration of fluid mobile (e.g. Ba) and fluid immobile (e.g. Nb, Ta, Zr, Y) elements and other relevant trace-element ratios (e.g. Sr/Y). The results indicate that small amounts (<1 wt%) of both subducted sediments and slab-released fluids were added to the mantle sources of the Cay and Maca volcanoes and that, despite the very young age (<10 Ma) of the oceanic lithosphere subducted beneath the volcanoes, slab melts were not involved in the magma genesis. Notwithstanding the proximity of the Cay and Maca magma sources to the northern edge of the slab window generated by the subduction of the Chile ridge under the South American plate, we did not find any geochemical evidence for a contribution of a subslab asthenospheric mantle. However, this mantle has been used

  9. ESO and Chile: 10 Years of Productive Scientific Collaboration

    NASA Astrophysics Data System (ADS)

    2006-06-01

    ESO and the Government of Chile launched today the book "10 Years Exploring the Universe", written by the beneficiaries of the ESO-Chile Joint Committee. This annual fund provides grants for individual Chilean scientists, research infrastructures, scientific congresses, workshops for science teachers and astronomy outreach programmes for the public. In a ceremony held in Santiago on 19 June 2006, the European Organisation for Astronomical Research in the Southern Hemisphere (ESO) and the Chilean Ministry of Foreign Affairs marked the 10th Anniversary of the Supplementary Agreement, which granted to Chilean astronomers up to 10 percent of the total observing time on ESO telescopes. This agreement also established an annual fund for the development of astronomy, managed by the so-called "ESO-Chile Joint Committee". ESO PR Photo 21/06 ESO PR Photo 21/06 Ten Years ESO-Chile Agreement Ceremony The celebration event was hosted by ESO Director General, Dr. Catherine Cesarsky, and the Director of Special Policy for the Chilean Ministry of Foreign Affairs, Ambassador Luis Winter. "ESO's commitment is, and always will be, to promote astronomy and scientific knowledge in the country hosting our observatories", said ESO Director General, Dr. Catherine Cesarsky. "We hope Chile and Europe will continue with great achievements in this fascinating joint adventure, the exploration of the universe." On behalf of the Government of Chile, Ambassador Luis Winter outlined the historical importance of the Supplementary Agreement, ratified by the Chilean Congress in 1996. "Such is the magnitude of ESO-Chile Joint Committee that, only in 2005, this annual fund represented 8 percent of all financing sources for Chilean astronomy, including those from Government and universities", Ambassador Winter said. The ESO Representative and Head of Science in Chile, Dr. Felix Mirabel, and the appointed Chilean astronomer for the ESO-Chile Joint Committee, Dr. Leonardo Bronfman, also took part in the

  10. Integrated melt inclusion and crystal zoning study to track the timescales and pre-eruption dynamics of violent Strombolian eruptions at Llaima volcano, Chile

    NASA Astrophysics Data System (ADS)

    Ruth, D. C.; Costa Rodriguez, F.; Bouvet de Maisonneuve, C.; Calder, E. S.

    2013-12-01

    Melt inclusion compositions in crystals from many volcanic systems are notoriously variable and some times difficult to interpret. Their compositions can be a combination of rapid crystal growth, entrapment of local melt, and diffusive re-equilibration, among other processes. Additionally, chemical zoning in olivine records changing environmental conditions, most importantly temperature and magma composition. Many geochemical studies focus on either melt inclusion data or chemical zoning data to ascertain volcanic processes. Here we combine melt inclusion data with that of chemical zoning of the olivine host crystals from the 2008 violent Strombolian eruption of Llaima volcano, Chile, to obtain a more refined understanding of the processes related to crystal growth, melt inclusion formation, and magma dynamics. We investigated zoning characteristics in a suite of olivine crystals, created X-ray element maps (Al, Ca, Mg, P, Fe), and collected quantitative elemental abundances across chemical zones for detailed diffusion modeling. Melt inclusion compositions were collected via electron microprobe analysis and LA-ICPMS. We observe three types of zoning in the host olivine crystals: normal, reverse, and multiple zones with fluctuating Fo content. Reverse zoning was more common than the other types. Regardless of zoning character, multiple melt inclusions are present within a given olivine, often found near the crystal rim. For some of these melt inclusions, the olivine surrounding the melt inclusion was also zoned, often to a similar composition as the olivine rim. This implies that these inclusions remained connected with interstitial matrix melt until melt inclusion closure. These ';open' melt inclusions exhibited slightly different major (higher SiO2, Na2O+K2O, TiO2) and trace elements (positive Eu and Sr anomalies) compared to melt inclusions in the same olivine that were not surrounded by compositional zoning. Quantitative elemental profiles produce modeled

  11. Mercury concentration variability in the zooplankton of the southern Baltic coastal zone

    NASA Astrophysics Data System (ADS)

    Bełdowska, Magdalena; Mudrak-Cegiołka, Stella

    2017-12-01

    Being a toxic element, mercury is introduced to the human organism through the consumption of fish and seafood, which in turn often feed on zooplankton. The bioaccumulation of Hg by zooplankton is an important factor influencing the magnitude of the mercury load introduced with food into the predator organism. Therefore the present article attempts to identify the processes and factors influencing Hg concentration in the zooplankton of the coastal zone, an area where marine organisms - an attractive food source for humans - thrive. This is particularly important in areas where climate changes influence the species composition and quantity of plankton. The studies were carried out on three test sites in the coastal zone of the southern Baltic Sea in the period from December 2011 to May 2013. The obtained results show that the shorting of the winter season is conducive to Hg increase in zooplankton and, consequently, in the trophic chain. High mercury concentrations were measured in genus Synchaeta and Keratella when Mesodinium rubrum were predominant in phytoplankton, while other sources of this metal in the plankton fauna were epilithon, epiphton and microbenthos. This is of particular importance when it comes to sheltered bays and estuaries with low water dynamics.

  12. An enigmatic plant-eating theropod from the Late Jurassic period of Chile.

    PubMed

    Novas, Fernando E; Salgado, Leonardo; Suárez, Manuel; Agnolín, Federico L; Ezcurra, Martín D; Chimento, Nicolás R; de la Cruz, Rita; Isasi, Marcelo P; Vargas, Alexander O; Rubilar-Rogers, David

    2015-06-18

    Theropod dinosaurs were the dominant predators in most Mesozoic era terrestrial ecosystems. Early theropod evolution is currently interpreted as the diversification of various carnivorous and cursorial taxa, whereas the acquisition of herbivorism, together with the secondary loss of cursorial adaptations, occurred much later among advanced coelurosaurian theropods. A new, bizarre herbivorous basal tetanuran from the Upper Jurassic of Chile challenges this conception. The new dinosaur was discovered at Aysén, a fossil locality in the Upper Jurassic Toqui Formation of southern Chile (General Carrera Lake). The site yielded abundant and exquisitely preserved three-dimensional skeletons of small archosaurs. Several articulated individuals of Chilesaurus at different ontogenetic stages have been collected, as well as less abundant basal crocodyliforms, and fragmentary remains of sauropod dinosaurs (diplodocids and titanosaurians).

  13. Columnar travertines: bio-influenced genesis, Porcelana Geysers, Northern Patagonia, Chile

    NASA Astrophysics Data System (ADS)

    Ruiz, B. S.; Morata, D.; Díez, B.; Daniele, L.

    2017-12-01

    Porcelana Geysers are located on the slopes of Barranco Colorado volcano, southern Chile, and is characterized by having a lateral hydrothermal fluid transport and an important CO2 content, having high gas exsolution rates on the surface at temperatures above 80°C. But it does not seem to be enough to explain the genesis of columnar travertines more than 3 meters high, considering that precipitation rates counteracts erosive rates due to rainy climate of the zone and the high slope gradient (>10 mm/h). The presence of extremophilic microbial diversity could explain this exceptional travertine morphology, particularly Phyla Cyanobacteria, Bacteroidetes and Order Thermales, which is evidenced by the vast visible presence of extracellular polymeric substances (EPS), reducing conditions in hot springs waters, microscopic and macroscopic textures and isotopic compositions of travertines, which are lower than the values that thermogenic travertines usually present (δ13C values from -4.85‰ to -3.37‰). These biotic processes would increase total dissolved gas pressure and [CO2]AQ values (over 0.05 mmol/L), and hence making the hydrostatic and bubbling pressure lower in the geysers vent fluids, which increases the amount of bubbles and their size and precipitation total rate of calcium carbonate (about 0.003 mm/h)

  14. Tectonic lineaments in the cenozoic volcanics of southern Guatemala: Evidence for a broad continental plate boundary zone

    NASA Technical Reports Server (NTRS)

    Baltuck, M.; Dixon, T. H.

    1984-01-01

    The northern Caribbean plate boundary has been undergoing left lateral strike slip motion since middle Tertiary time. The western part of the boundary occurs in a complex tectonic zone in the continental crust of Guatemala and southernmost Mexico, along the Chixoy-Polochic, Motogua and possibly Jocotan-Chamelecon faults. Prominent lineaments visible in radar imagery in the Neogene volcanic belt of southern Guatemala and western El Salvador were mapped and interpreted to suggest southwest extensions of this already broad plate boundary zone. Because these extensions can be traced beneath Quaternary volcanic cover, it is thought that this newly mapped fault zone is active and is accommodating some of the strain related to motion between the North American and Caribbean plates. Onshore exposures of the Motoqua-Polochic fault systems are characterized by abundant, tectonically emplaced ultramafic rocks. A similar mode of emplacement for these off shore ultramafics, is suggested.

  15. Paleomagnetic Data Bearing on the Evolution of the Walker Lane Belt Transfer Zone From mid-Miocene to Present: an Investigation of the Inferred Southern and Eastern Boundaries.

    NASA Astrophysics Data System (ADS)

    Grow, J. S.; Geissman, J. W.; Oldow, J. S.

    2008-12-01

    The Walker Lane Belt (WLB) transfer zone, which initiated in the mid-Miocene, presently links the Eastern California Shear Zone (ECSZ) in the south to the Central Nevada Seismic Belt (CNSB) and WLB to the east and north, respectively. This transfer zone is part of a diffuse intracontinental deformation zone that accommodates some 25 percent of the current motion between the North American and Pacific plates. The boundary of the transfer system is clear on the northern and western margins but the extent of the system to the south and east is only inferred. The extent of deformation and development of the WLB transfer zone since the mid-Miocene is being examined by a paleomagnetic study of 125 sites that includes Miocene to mid-Pliocene volcanic and shallow intrusive rocks near the inferred southern and eastern boundaries. Results from 39 sites inside and along the southern boundary (i.e. Goldfield Hills, Montezuma Range, Clayton Ridge) show about 30° of clockwise rotation (D = 028.3°, I = 57.8°, α95 = 3.9°, discordant from the expected Neogene direction of D = 358°, I = 55°). The area where 13 of these 39 sites are located (i.e. northern Amargosa Range, eastern Slate Ridge) was previously thought to lie outside of the inferred boundary, yet it also shows about 30° of clockwise rotation (D = 031.2°, I = 52.4°, α95 = 6.7°). Areas along the eastern boundary (i.e. southern San Antonio Range) of the transfer zone are still under investigation; data obtained to date are not internally consistent. Overall, the available paleomagnetic data suggest that the southern extent of the WLB transfer zone was larger than previously expected during the mid-Miocene to mid-Pliocene, and based on previous paleomagnetic, structural, and geodetic studies of the area, support a transition from more diffuse to localized deformation (forming the Mina Deflection) at about 3 Ma.

  16. Coulomb Stress Change and Seismic Hazard of Rift Zones in Southern Tibet after the 2015 Mw7.8 Nepal Earthquake and Its Mw7.3 Aftershock

    NASA Astrophysics Data System (ADS)

    Dai, Z.; Zha, X.; Lu, Z.

    2015-12-01

    In southern Tibet (30~34N, 80~95E), many north-trending rifts, such as Yadong-Gulu and Lunggar rifts, are characterized by internally drained graben or half-graben basins bounded by active normal faults. Some developed rifts have become a portion of important transportation lines in Tibet, China. Since 1976, eighty-seven >Mw5.0 earthquakes have happened in the rift regions, and fifty-five events have normal faulting focal mechanisms according to the GCMT catalog. These rifts and normal faults are associated with both the EW-trending extension of the southern Tibet and the convergence between Indian and Tibet. The 2015 Mw7.8 Nepal great earthquake and its Mw7.3 aftershock occurred at the main Himalayan Thrust zone and caused tremendous damages in Kathmandu region. Those earthquakes will lead to significant viscoelastic deformation and stress changes in the southern Tibet in the future. To evaluate the seismic hazard in the active rift regions in southern Tibet, we modeled the slip distribution of the 2015 Nepal great earthquakes using the InSAR displacement field from the ALOS-2 satellite SAR data, and calculated the Coulomb failure stress (CFS) on these active normal faults in the rift zones. Because the estimated CFS depends on the geometrical parameters of receiver faults, it is necessary to get the accurate fault parameters in the rift zones. Some historical earthquakes have been studied using the field data, teleseismic data and InSAR observations, but results are in not agreement with each other. In this study, we revaluated the geometrical parameters of seismogenic faults occurred in the rift zones using some high-quality coseismic InSAR observations and teleseismic body-wave data. Finally, we will evaluate the seismic hazard in the rift zones according to the value of the estimated CFS and aftershock distribution.

  17. Geographical distribution and phylogenetic analysis of Rhipicephalus sanguineus sensu lato in northern and central Chile.

    PubMed

    Díaz, Fabián E; Martínez-Valdebenito, Constanza; López, Javier; Weitzel, Thomas; Abarca, Katia

    2018-05-01

    The presented study analyzed the presence and geographical distribution of the tropical and temperate lineages of Rhipicephalus sanguineus sensu lato in Chile. R. sanguineus s.l. ticks were collected from dogs at 14 sites in northern and central Chile for morphological and genetic analysis based on the 16S rDNA gene. Phylogenetic studies proved the existence of both, the tropical and the temperate lineages. The former was represented by a single haplotype and occurred in the far north; the latter included four haplotypes and was observed from the Tarapacá Region southwards. In four sites at latitudes from 20°S to 22°S, both lineages were found to coexist. Our study discovered for the first time the existence of the tropical lineage in Chile and demonstrated that distributions of the tropical and temperate lineages overlap, forming a transitional zone of approximately 200 km in northern coastal Chile. Copyright © 2018 Elsevier GmbH. All rights reserved.

  18. Implementing an Education and Outreach Program for the Gemini Observatory in Chile.

    NASA Astrophysics Data System (ADS)

    Garcia, M. A.

    2006-08-01

    Beginning in 2001, the Gemini Observatory began the development of an innovative and aggressive education and outreach program at its Southern Hemisphere site in northern Chile. A principal focus of this effort is centered on local education and outreach to communities surrounding the observatory and its base facility in La Serena Chile. Programs are now established with local schools using two portable StarLab planetaria, an internet-based teacher exchange called StarTeachers and multiple partnerships with local educational institutions. Other elements include a CD-ROM-based virtual tour that allows students, teachers and the public to experience the observatory's sites in Chile and Hawaii. This virtual environment allows interaction using a variety of immersive scenarios such as a simulated observation using real data from Gemini. Pilot projects like "Live from Gemini" are currently being developed which use internet videoconferencing technologies to bring the observatory's facilities into classrooms at universities and remote institutions. Lessons learned from the implementation of these and other programs will be introduced and the challenges of developing educational programming in a developing country will be shared.

  19. Seismology in Chile

    USGS Publications Warehouse

    Kausel, E.

    1983-01-01

    The Department of Geology and Geophysics, which is under the faculties of Mathematics and Physical Sciences of the University of Chile, is the organization that is responsible for the Seismological Service of Chile and for installing,operating, and maintaining the seismological stations as well as all the strong-motion stations in Chile.

  20. The Relationship between Teachers Commitment and Female Students Academic Achievements in Some Selected Secondary School in Wolaita Zone, Southern Ethiopia

    ERIC Educational Resources Information Center

    Bibiso, Abyot; Olango, Menna; Bibiso, Mesfin

    2017-01-01

    The purpose of this study was to investigate the relationship between teacher's commitment and female students academic achievement in selected secondary school of Wolaita zone, Southern Ethiopia. The research method employed was survey study and the sampling techniques were purposive, simple random and stratified random sampling. Questionnaire…

  1. Coastal deformation and sea-level changes in the northern Chile subduction area (23$deg;S) during the last 330 ky

    NASA Astrophysics Data System (ADS)

    Ortlieb, Luc; Zazo, Cari; Goy, JoséLuis; Hillaire-Marcel, Claude; Ghaleb, Bassam; Cournoyer, Louise

    The Nazca-South American plate boundary is a subduction zone where a relatively complex pattern of vertical deformation can be inferred from the study of emerged marine terraces. Along the coasts of southern Peru and northern Chile, the vertical distribution of remnants of Pleistocene terraces suggests that a crustal, large scale uplift motion is combined with more regional/local tectonic processes. In northern Chile, the area of Hornitos (23°S) offers a remarkable sequence of well-defined marine terraces that may be dated through U-series and aminostratigraphic studies on mollusc shells. The unusual preservation of the landforms and of the shell material, which enabled the age determination of the deposits, is largely due to the lengthy history of extreme aridity in this area. The exceptional record of late Middle Pleistocene to Late Pleistocene high seastands is also favoured by the slight warping of two distinct fault blocks that have enhanced the morphostratigraphic relationships between the distinct coastal units. Detailed geomorphological, sedimentological and chronostratigraphic studies of the Hornitos area led to the identification, with reasonable confidence, of the depositional remnants of sea-level maxima coeval with the Oxygen Isotope Substages 5c, 5e, 7 (probably two episodes) and the isotope stage 9 (series of beach ridges). The coastal plain, at the foot of the major Coastal Escarpment of northern Chile, appears to have been uplifted at a mean rate of 240 mm/ky in the course of the last 330 ky. From the elevation of the older terraces and late Pliocene shorelines, it can be inferred that these steady vertical motions were much more rapid than during the Early Pleistocene.

  2. Artificial and natural radionuclides in soils of the southern and middle taiga zones of Komi Republic

    NASA Astrophysics Data System (ADS)

    Beznosikov, V. A.; Lodygin, E. D.; Shuktomova, I. I.

    2017-07-01

    Specific activities of artificial (137Cs, 90Sr) and natural (40K, 232Th, 226Ra) radionuclides in background soils of southern and middle taiga of Komi Republic have been estimated with consideration for the landscape-geochemical features of the territory. It has been shown that their accumulation and migration in soils are determined by the following factors: position in relief, texture, and organic matter content. No anomalous zones with increased contents of radionuclides in soils have been revealed.

  3. Geomorphic evidence of Quaternary tectonics within an underlap fault zone of southern Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Giano, Salvatore Ivo; Pescatore, Eva; Agosta, Fabrizio; Prosser, Giacomo

    2018-02-01

    A composite seismic source, the Irpinia - Agri Valley Fault zone, located in the axial sector of the fold-and-thrust belt of southern Apennines, Italy, is investigated. This composite source is made up of a series of nearly parallel, NW-striking normal fault segments which caused many historical earthquakes. Two of these fault segments, known as the San Gregorio Magno and Pergola-Melandro, and the fault-related mountain fronts, form a wedge-shaped, right-stepping, underlap fault zone. This work is aimed at documenting tectonic geomorphology and geology of this underlap fault zone. The goal is to decipher the evidence of surface topographic interaction between two bounding fault segments and their related mountain fronts. In particular, computation of geomorphic indices such as mountain front sinuosity (Smf), water divide sinuosity (Swd), asymmetry factor (AF), drainage basin elongation (Bs), relief ratio (Rh), Hypsometry (HI), normalized steepness (Ksn), and concavity (θ) is integrated with geomorphological analysis, the geological mapping, and structural analysis in order to assess the recent activity of the fault scarp sets recognized within the underlap zone. Results are consistent with the NW-striking faults as those showing the most recent tectonic activity, as also suggested by presence of related slope deposits younger than 38 ka. The results of this work therefore show how the integration of a multidisciplinary approach that combines geomorphology, morphometry, and structural analyses may be key to solving tectonic geomorphology issues in a complex, fold-and-thrust belt configuration.

  4. Military Activities in the Exclusive Economic Zone: Preventing Uncertainty and Defusing Conflict

    DTIC Science & Technology

    2002-03-01

    citing Presidential Declaration Concerning Continental Shelf of 23 June 1947, EL MERCURIO, Santiago de Chile (June 29, 1947), and Presidential Decree...Presidential Declaration Concerning Continental Shelf of 23 June 1947, EL MERCURIO, Santiago de Chile June 29, 1947). Peru also established a 200...Organization, 1987); James E. Bailey, Comment, The Exclusive Economic Zone: Its De - velopment and Future in International and Domestic Law, 45 LA. L

  5. Seismicity and structure of Nazca Plate subduction zone in southern Peru

    NASA Astrophysics Data System (ADS)

    Lim, H.; Kim, Y.; Clayton, R. W.; Thurber, C. H.

    2016-12-01

    We define subducting plate geometries in the Nazca subduction zone by (re)locating intra-slab earthquakes in southern Peru (2-18°S) and taking previously published converted phase analysis results, to clarify the slab geometry and inferred relationships to the seismicity. We also provide both P- and S-wave velocities of the subducting Nazca Plate and mantle wedge portions close to the slab using double-difference tomography (Zhang and Thurber, 2003) to understand upper plate volcanism and subduction process. A total of 492 regional earthquakes from August 2008 to February 2013 recorded from the dense seismic array (PeruSE, 2013) are selected for the relocation and tomography. The relocated seismicity shows a smooth contortion in the slab-dip transition zone for 400 km between the shallow (25°)-to-flat dipping interface in the north and 40°-dipping interface in the south. We find a significant slab-dip difference (up to 10°) between our results and previously published slab models along the profile region sampling the normal-dip slab at depth (>100 km). Robust features in both P- and S-wave tomography inversions are dipping low-velocity slabs down to 100 km transitioning to higher-velocities at 100-140 km in both flat slab and dipping slab regions. Differences in the velocities of the mantle wedge between the two regions may indicate different hydration states in the wedge.

  6. Rainfall erosivity in Central Chile

    NASA Astrophysics Data System (ADS)

    Bonilla, Carlos A.; Vidal, Karim L.

    2011-11-01

    SummaryOne of the most widely used indicators of potential water erosion risk is the rainfall-runoff erosivity factor ( R) of the Revised Universal Soil Loss Equation (RUSLE). R is traditionally determined by calculating a long-term average of the annual sum of the product of a storm's kinetic energy ( E) and its maximum 30-min intensity ( I30), known as the EI30. The original method used to calculate EI30 requires pluviograph records for at most 30-min time intervals. Such high resolution data is difficult to obtain in many parts of the world, and processing it is laborious and time-consuming. In Chile, even though there is a well-distributed rain gauge network, there is no systematic characterization of the territory in terms of rainfall erosivity. This study presents a rainfall erosivity map for most of the cultivated land in the country. R values were calculated by the prescribed method for 16 stations with continuous graphical record rain gauges in Central Chile. The stations were distributed along 800 km (north-south), and spanned a precipitation gradient of 140-2200 mm yr -1. More than 270 years of data were used, and 5400 storms were analyzed. Additionally, 241 spatially distributed R values were generated by using an empirical procedure based on annual rainfall. Point estimates generated by both methods were interpolated by using kriging to create a map of rainfall erosivity for Central Chile. The results show that the empirical procedure used in this study predicted the annual rainfall erosivity well (model efficiency = 0.88). Also, an increment in the rainfall erosivities was found as a result of the rainfall depths, a regional feature determined by elevation and increasing with latitude from north to south. R values in the study area range from 90 MJ mm ha -1 h -1 yr -1 in the north up to 7375 MJ mm ha -1 h -1 yr -1 in the southern area, at the foothills of the Andes Mountains. Although the map and the estimates could be improved in the future by

  7. Hydrothermal Exploration at the Chile Triple Junction - ABE's last adventure?

    NASA Astrophysics Data System (ADS)

    German, C. R.; Shank, T. M.; Lilley, M. D.; Lupton, J. E.; Blackman, D. K.; Brown, K. M.; Baumberger, T.; Früh-Green, G.; Greene, R.; Saito, M. A.; Sylva, S.; Nakamura, K.; Stanway, J.; Yoerger, D. R.; Levin, L. A.; Thurber, A. R.; Sellanes, J.; Mella, M.; Muñoz, J.; Diaz-Naveas, J. L.; Inspire Science Team

    2010-12-01

    In February and March 2010 we conducted preliminary exploration for hydrothermal plume signals along the East Chile Rise where it intersects the continental margin at the Chile Triple Junction (CTJ). This work was conducted as one component of our larger NOAA-OE funded INSPIRE project (Investigation of South Pacific Reducing Environments) aboard RV Melville cruise MV 1003 (PI: Andrew Thurber, Scripps) with all shiptime funded through an award of the State of California to Andrew Thurber and his co-PI's. Additional support came from the Census of Marine Life (ChEss and CoMarge projects). At sea, we conducted a series of CTD-rosette and ABE autonomous underwater vehicle operations to prospect for and determine the nature of any seafloor venting at, or adjacent to, the point where the the East Chile Rise subducts beneath the continental margin. Evidence from in situ sensing (optical backscatter, Eh) and water column analyses of dissolved CH4, δ3He and TDFe/TDMn concentrations document the presence of two discrete sites of venting, one right at the triple junction and the other a further 10km along axis, north of the Triple Junction, but still within the southernmost segment of the East Chile Rise. From an intercomparison of the abundance of different chemical signals we can intercompare likely characteristics of these differet source sites and also differentiate between them and the high methane concentrations released from cold seep sites further north along the Chile Margin, both with the CTJ region and also at the Concepcion Methane Seep Area (CMSA). This multi-disciplinary and international collaboration - involving scientists from Chile, the USA, Europe and Japan - can serve as an excellent and exciting launchpoint for wide-ranging future investigations of the Chile Triple Junction area - the only place on Earth where an oceanic spreading center is being actively subducted beneath a continent and also the only place on Earth where all known forms of deep

  8. Chile.

    PubMed

    1992-05-01

    The background notes on Chile provide a statistical summary of the population, geography, government, and the economy, and more descriptive text on the history, population, government, economy, defense, and foreign relations. In brief, Chile has 13.3 million Spanish Indian (Mestizos), European, and Indian inhabitants and an annual growth rate of 1.6%. 96% are literate. Infant mortality is 18/1000. 34% of the population are involved in industry and commerce, 30% in services, 19% in agriculture and forestry and fishing, 7% in construction, and 2% in mining. The major city is Santiago. The government, which gained independence in 1810, is a republic with executive, legislative, and judicial branches. There are 12 regions. There are 6 major political parties. Suffrage is universal at 18 years. Gross domestic product (GDP) is $29.2 billion. The annual growth rate is 5% and inflation is 19%. Copper, timber, fish, iron ore, nitrates, precious metals, and molybdenum are its natural resources. Agricultural products are 9% of GDP and include wheat, potatoes, corn, sugar beets, onions, beans, fruits, and livestock. Industry is 21% of GDP and includes mineral refining, metal manufacturing, food and fish processing, paper and wood products, and finished textiles. $8.3 billion is the value of exports and $7 billion of imports. Export markets are in Japan, the US, Germany, Brazil, and the United Kingdom. Chile received $3.5 billion in economic aid between 1949-85, but little in recent years. 83% live in urban centers, principally around Santiago. Congressional representation is made on the basis of elections by a unique binomial majority system. Principal government officials are identified. Chile has a diversified free market economy and is almost self-sufficient in food production. The US is a primary trading partner. 49% of Chile's exports are minerals. Chile maintains diplomatic relations with 70 countries, however, relations are strained with Argentina and Bolivia. Relations

  9. Constraining the hydration of the subducting Nazca plate beneath Northern Chile using subduction zone guided waves

    NASA Astrophysics Data System (ADS)

    Garth, Tom; Rietbrock, Andreas

    2017-09-01

    Guided wave dispersion is observed from earthquakes at 180-280 km depth recorded at stations in the fore-arc of Northern Chile, where the 44 Ma Nazca plate subducts beneath South America. Characteristic P-wave dispersion is observed at several stations in the Chilean fore-arc with high frequency energy (>5 Hz) arriving up to 3 s after low frequency (<2 Hz) arrivals. This dispersion has been attributed to low velocity structure within the subducting Nazca plate which acts as a waveguide, retaining and delaying high frequency energy. Full waveform modelling shows that the single LVL proposed by previous studies does not produce the first motion dispersion observed at multiple stations, or the extended P-wave coda observed in arrivals from intermediate depth events within the Nazca plate. These signals can however be accurately accounted for if dipping low velocity fault zones are included within the subducting lithospheric mantle. A grid search over possible LVL and faults zone parameters (width, velocity contrast and separation distance) was carried out to constrain the best fitting model parameters. Our results imply that fault zone structures of 0.5-1.0 km thickness, and 5-10 km spacing, consistent with observations at the outer rise are present within the subducted slab at intermediate depths. We propose that these low velocity fault zone structures represent the hydrated structure within the lithospheric mantle. They may be formed initially by normal faults at the outer rise, which act as a pathway for fluids to penetrate the deeper slab due to the bending and unbending stresses within the subducting plate. Our observations suggest that the lithospheric mantle is 5-15% serpentinised, and therefore may transport approximately 13-42 Tg/Myr of water per meter of arc. The guided wave observations also suggest that a thin LVL (∼1 km thick) interpreted as un-eclogitised subducted oceanic crust persists to depths of at least 220 km. Comparison of the inferred seismic

  10. Processes controlling the composition of precipitation at a remote southern hemispheric location: Torres del Paine National Park, Chile

    NASA Astrophysics Data System (ADS)

    Galloway, James N.; Keene, William C.; Likens, Gene E.

    1996-03-01

    Precipitation composition measured at Torres del Paine National Park, Chile (TdP) (51°10'S, 71°58'W), between 1984 and 1993 was acidic (volume-weighted-average pH of 4.96) with a dilute seawater component. H+ was the dominant non-sea-salt (nss) cation; in decreasing order of abundance, nss anions were HCOO-, Cl-, SO4=, CH3COO-, and NO3-. Relative to lower latitude, remote locations, concentrations and per-event depositions of nss SO4=, NO3-, and NH4+ at TdP were lower; those of HCOOt (HCOO- + HCOOH) and CH3COOHt, (CH3COO- and CH3COOH) were similar; and those of CH3SO3- were higher. Concentrations and deposition fluxes of HCOOt, CH3COOt, nss SO4=, CH3SO3-, and NH4+ varied seasonally with summer maxima and winter minima. Carboxylic acids probably originated from both direct terrestrial emissions and oxidation of hydrocarbons emitted by marine and terrestrial biota. Nss SO4= and CH3SO3- originated primarily from oxidation of biogenic (CH3)2S emitted from the southern Pacific Ocean. Direct emissions of NH3 from upwind terrestrial and marine ecosystems probably accounted for most observed NH4+. NO3- concentrations and depositions were highest during the latter part of austral winter and spring suggesting abiotic controls. Transport of precursors from lightning, biomass burning, and fossil-fuel combustion at lower latitudes and possibly transport of reactive N from the stratosphere apparently contributed oxidized N to the southern Patagonian troposphere. Although the ionic strength of precipitation at TdP is currently among the world's lowest, future changes are likely because of increases in local and regional population and energy and food production.

  11. The role of detachment and interlayer shear zones in the structural evolution of the southern Espinhaço range, eastern Brazil

    NASA Astrophysics Data System (ADS)

    Kuchenbecker, Matheus; Sanglard, Júlio Carlos Destro

    2018-07-01

    Sedimentary rocks usually show a significant mechanical anisotropy due to its layered nature. Because of this, they play an important role controlling rock deformation and the study of the deformation partitioning caused by rheological heterogeneities becomes a crucial step to understand the inversion of sedimentary basins. The detachment and interlayer shear zones, described at southern Espinhaço range, correspond to part of the structural collection that records the compressive deformation which is associated to the Brazilian-Pan African orogeny during Gondwana amalgamation. The mechanical contrast between lithological units is the main parameter of control for the occurrence of these zones which can be found with variable thickness from millimeter interlayer shear zones to regional-sized basement-cover detachment zones. The phyllitic layers are the most incompetent lithotype among metasedimentary rocks and they play an important role in the ductile-brittle regional deformation by accommodating much of the deformation during faulting and/or folding. Even though being a more competent rock, internal interlayer shear zones and other shear structures can be found in quartzite when in contact with weaker rocks. These structures accommodate a significant amount of deformation at the southern Espinhaço range and, because of this, they are of great value in understanding the inversion of the Espinhaço basins during West Gondwana assembly. The focus of the present paper is to discuss the main situations where interlayer shear occurs, to present a brief compendium of the main structures associated to this process and to add parameters to its recognition and interpretation.

  12. Weather Type classification over Chile; patterns, trends, and impact in precipitation and temperature

    NASA Astrophysics Data System (ADS)

    Frias, T.; Trigo, R. M.; Garreaud, R.

    2009-04-01

    The Andes Cordillera induces considerable disturbances on the structure and evolution of the pressure systems that influences South America. Different weather types for southern South America are derived from the daily maps of geopotential height at 850hPa corresponding to a 42 year period, spanning from 1958 to 2000. Here we have used the ECWMF ERA-40 reanalysis dataset to construct an automated version of the Lamb Weather type (WTs) classification scheme (Jones et al., 1993) developed for the UK. We have identified 8 basic WTs (Cyclonic, Anticyclonic and 6 main directional types) following a similar methodology to that previously adopted by Trigo and DaCamara, 2000 (for Iberia). This classification was applied to two regions of study (CLnorth and CLsouth) which differ 20° in latitude, so that the vast Chile territory could be covered. Then were assessed the impact of the occurrence of this weather types in precipitation in Chile, as well as in the distribution of precipitation and temperature fields (reanalysis data) in southern half of South America. The results allow to conclude that the precipitation in central region of Chile is largely linked with the class occurrence (concerning CLnorth) of cyclonic circulation and of West quadrant (SW, W and NW), despite of it's relatively low frequency. In CLsouth, for its part, it is verified that the most frequent circulation is from the west quadrant, although the associated amount of rainfall is lower than in CLnorth. There was also a general decrease of precipitation at local weather stations chosen in the considered period of study, particularly in austral winter.

  13. Chile stand management for mechanical green chile harvest

    USDA-ARS?s Scientific Manuscript database

    Currently the red chile crop is mechanically harvested. Because the pods will be dehydrated before consumption, breakage and bruising of red pods is not a concern. Green chile, however, is currently hand harvested because of the fragile nature of the fruit and the need to avoid pod damage. Hand h...

  14. Dissolved methane concentration and flux in the coastal zone of the Southern California Bight-Mexican sector: Possible influence of wastewater

    EPA Science Inventory

    We measured dissolved methane concentrations ([CH4]) in the coastal zone of the Southern California Bight-Mexican sector (SCBMex) during two cruises: S1 in the USA–Mexico Border Area (BA) during a short rainstorm and S2 in the entire SCBMex during a drier period a few days later....

  15. Tourism in Chile | CTIO

    Science.gov Websites

    Program PIA Program GO-FAAR Program Other Opportunities Tourism Visits to Tololo Astro tourism in Chile Tourism in Chile Information for travelers Visit Tololo Media Relations News Press Release Publications ‹› You are here CTIO Home » Outreach » Tourism » Tourism in Chile Tourism in Chile Map of

  16. Differential invasion success of salmonids in southern Chile: patterns and hypotheses

    USGS Publications Warehouse

    Arismendi, Ivan; Penaluna, Brooke E.; Dunham, Jason B.; García de Leaniz, Carlos; Soto, Doris; Fleming, Ian A.; Gomez-Uchidam, Daniel; Gajardo, Gonzalo; Vargas, Pamela V.; León-Muñoz, Jorge

    2014-01-01

    Biological invasions create complex ecological and societal issues worldwide. Most of the knowledge about invasions comes only from successful invaders, but less is known about which processes determine the differential success of invasions. In this review, we develop a framework to identify the main dimensions driving the success and failure of invaders, including human influences, characteristics of the invader, and biotic interactions. We apply this framework by contrasting hypotheses and available evidence to explain variability in invasion success for 12 salmonids introduced to Chile. The success of Oncorhynchus mykiss and Salmo trutta seems to be influenced by a context-specific combination of their phenotypic plasticity, low ecosystem resistance, and propagule pressure. These well-established invaders may limit the success of subsequently introduced salmonids, with the possible exception of O. tshawytscha, which has a short freshwater residency and limited spatial overlap with trout. Although propagule pressure is high for O. kisutch and S. salar due to their intensive use in aquaculture, their lack of success in Chile may be explained by environmental resistance, including earlier spawning times than in their native ranges, and interactions with previously established and resident Rainbow Trout. Other salmonids have also failed to establish, and they exhibit a suite of ecological traits, environmental resistance, and limited propagule pressure that are variably associated with their lack of success. Collectively, understanding how the various drivers of invasion success interact may explain the differential success of invaders and provide key guidance for managing both positive and negative outcomes associated with their presence.

  17. Strain Variation in Accretionary Prisms Across Space and Time: Insights from the Makran Subduction Zone

    NASA Astrophysics Data System (ADS)

    Penney, C.; Tavakoli, F.; Saadat, A.; Nankali, H. R.; Sedighi, M.; Khorrami, F.; Sobouti, F.; Rafi, Z.; Copley, A.; Jackson, J. A.; Priestley, K. F.

    2017-12-01

    The Makran is one of the world's least-studied subduction zones. In particular, little is known about the accumulation and accommodation of strain in the onshore part of the subduction zone, which parallels the coasts of southern Iran and Pakistan. The deformation of the Makran accretionary prism results from both its subduction zone setting and N-S right-lateral shear between central Iran and Afghanistan. North of the Makran, this shear is accommodated by a series of right-lateral faults which offset the rocks of the Sistan Suture Zone, an abandoned accretionary prism. However, these right-lateral faults are not observed south of 27°N, and no major N-S faults cut the E-W trending structures of the Makran. How this right-lateral motion is accommodated at the southern end of the Sistan Suture Zone is a long-standing tectonic question. By combining results from geomorphology, GPS, seismology and modelling we conclude that right-lateral motion is transferred across the depression north of the accretionary prism to the region of right-lateral shear at the western end of the accretionary prism. This requires the Jaz Murian depression to be bounded by normal faults, consistent with the basin geomorphology. However, GPS data show compression across the margins of the basin, and no shallow normal-faulting earthquakes have been observed in the region. We therefore suggest that the behaviour of these faults may be time-dependent and controlled by the megathrust seismic cycle, as has been suggested elsewhere (e.g. Chile). Recent strike-slip earthquakes, including the 2013 Balochistan earthquake, have clustered at the prism's lateral edges, showing the importance of spatial, as well as temporal, variations in strain. These earthquakes have reactivated thrust faults in the Makran accretionary prism, showing that the style of strain within accretionary prisms can vary on multiple timescales and allowing us to calculate the coefficient of friction on the underlying megathrust.

  18. Low-temperature alteration of dredged volcanics from the Southern Chile Ridge: Additional information about early stages of seafloor weathering

    USGS Publications Warehouse

    Pichler, T.; Ridley, W.I.; Nelson, E.

    1999-01-01

    A suite of submarine volcanic rocks from the Southern Chile Ridge has been examined in order to investigate the early stages of low temperature alteration. Alteration in these samples proceeded as follows: (1) Fe-staining on sample surface and along fractures, (2) filling of vesicles with secondary material, (3) breakdown of glassy matrix, (4) breakdown of microcrystalline matrix, and (5) breakdown and replacement of olivine. Plagioclase and pyroxene were sometimes found to be slightly altered along internal fissures. Secondary or alteration phases generally showed high K (3-5 wt.%), Fe (30-70 wt.%) and low Al ( Rb > K. During initial stages of alteration the behavior of some trace elements such as rare-earth elements (REE), Ba, Zr, Hf, Ta, Nb, and Mo are solely controlled by the precipitation of Mn-rich Fe-oxyhydroxides. The preferred incorporation of Ce into Mn-rich Fe-oxyhydroxides may be a principal factor explaining the Ce depletion in seawater. We conclude that the earliest stages of submarine weathering are controlled by Eh and pH gradients between the rock and seawater. In the absence of a buffer, oxidation of ferrous iron causes a decrease in solution pH.

  19. 33 CFR 100.1104 - Southern California Annual Marine Events for the Los Angeles Long Beach Captain of the Port Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Events for the Los Angeles Long Beach Captain of the Port Zone. 100.1104 Section 100.1104 Navigation and... NAVIGABLE WATERS § 100.1104 Southern California Annual Marine Events for the Los Angeles Long Beach Captain... Description Competitive long distance sailboat race from Los Angeles to Honolulu. Date Bi-annually in early...

  20. Promoting Dark Sky Protection in Chile: the Gabriel Mistral IDA Dark Sky Sanctuary and Other AURA Initiatives

    NASA Astrophysics Data System (ADS)

    Smith, R. Chris; Smith, Malcolm; Pompea, Stephen; Sanhueza, Pedro; AURA-Chile EPO Team

    2018-01-01

    For over 20 years, AURA has been leading efforts promoting the protection of dark skies in northern Chile. Efforts began in the early 1990s at AURA's Cerro Tololo Inter-American Observatory (CTIO), working in collaboration with other international observatories in Chile including Las Campanas Observatory (LCO) and the European Southern Observatory (ESO). CTIO also partnered with local communities, for example supporting Vicuña's effort to establish the first municipal observatory in Chile. Today we have developed a multifaceted effort of dark sky protection, including proactive government relations at national and local levels, a strong educational and public outreach program, and a program of highlighting international recognition of the dark skies through the IDA Dark Sky Places program. Work on international recognition has included the declaration of the Gabriel Mistral IDA Dark Sky Sanctuary, the first such IDA sanctuary in the world.

  1. Megathrust earthquakes in Central Chile: What is next after the Maule 2010 earthquake?

    NASA Astrophysics Data System (ADS)

    Madariaga, R.

    2013-05-01

    The 27 February 2010 Maule earthquake occurred in a well identified gap in the Chilean subduction zone. The event has now been studied in detail using both far-field, near field seismic and geodetic data, we will review this information gathered so far. The event broke a region that was much longer along strike than the gap left over from the 1835 Concepcion earthquake, sometimes called the Darwin earthquake because he was in the area when the earthquake occurred and made many observations. Recent studies of contemporary documents by Udias et al indicate that the area broken by the Maule earthquake in 2010 had previously broken by a similar earthquake in 1751, but several events in the magnitude 8 range occurred in the area principally in 1835 already mentioned and, more recently on 1 December 1928 to the North and on 21 May 1960 (1 1/2 days before the big Chilean earthquake of 1960). Currently the area of the 2010 earthquake and the region immediately to the North is undergoing a very large increase in seismicity with numerous clusters of seismicity that move along the plate interface. Examination of the seismicity of Chile of the 18th and 19th century show that the region immediately to the North of the 2010 earthquake broke in a very large megathrust event in July 1730. this is the largest known earthquake in central Chile. The region where this event occurred has broken in many occasions with M 8 range earthquakes in 1822, 1880, 1906, 1971 and 1985. Is it preparing for a new very large megathrust event? The 1906 earthquake of Mw 8.3 filled the central part of the gap but it has broken again on several occasions in 1971, 1973 and 1985. The main question is whether the 1906 earthquake relieved enough stresses from the 1730 rupture zone. Geodetic data shows that most of the region that broke in 1730 is currently almost fully locked from the northern end of the Maule earthquake at 34.5°S to 30°S, near the southern end of the of the Mw 8.5 Atacama earthquake of 11

  2. Estimates of Abundance and Trend of Chilean Blue Whales off Isla de Chiloé, Chile.

    PubMed

    Galletti Vernazzani, Barbara; Jackson, Jennifer A; Cabrera, Elsa; Carlson, Carole A; Brownell, Robert L

    2017-01-01

    Since 1970, blue whales (Balaenoptera musculus) have been seen feeding in the waters off southern Chile during the summer and autumn (December to May). Investigation of the genetic, acoustic and morphological characteristics of these blue whales shows that they are a distinct but unnamed subspecies, called the Chilean blue whales. Photo-identification surveys have been conducted in the waters off northwestern Isla Grande de Chiloé, southern Chile from 2004-2012 and Isla Chañaral, central Chile in 2012. Over this time, 1,070 blue whales were encountered yielding, after photo-quality control, 318 and 267 unique photographs of the left and right side of the flank respectively. Using mark-recapture analysis of left and right side photographs collected from Isla Grande de Chiloé (2004-2012), open population models estimate that ~570-760 whales are feeding seasonally in this region. POPAN superpopulation abundance estimates for the same feeding ground in 2012 are 762 (95% confidence intervals, CI = 638-933) and 570 (95% CI 475-705) for left and right side datasets respectively, very similar to results from closed population models. Estimates of trend revealed strong variation in abundance, peaking in 2009 and [suggesting] fluctuating use in the survey area over time, likely related to the density of their prey. High inter-annual return rates suggest a degree of site-fidelity of individuals to Isla Grande de Chiloé and that the number of whales using this feeding ground is relatively small.

  3. Determinants and geographical variation in the distribution of depression in the Southern cone of Latin America: A population-based survey in four cities in Argentina, Chile and Uruguay.

    PubMed

    Daray, F M; Rubinstein, A L; Gutierrez, L; Lanas, F; Mores, N; Calandrelli, M; Poggio, R; Ponzo, J; Irazola, V E

    2017-10-01

    Depression is one of the major contributors to the global burden of diseases; however, population-based data in South America are limited. We conducted a population-based cross sectional study with 7524 participants, aged 35-74 years old, recruited between February 2010 and December 2011 from randomly selected samples in 4 cities (Bariloche and Marcos Paz, Argentina; Temuco, Chile; and Pando-Barros Blancos, Uruguay). Major Depressive Episode (MDE) was assessed using the Patient Health Questionnaire (PHQ) - 9. The overall prevalence of MDE was 14.6% (95% CI: 13.6, 15.6). However, there was a geographical variability of up to 3.7 folds between different cities being 5.6% (95% CI: 4.6, 6.7) in Marcos Paz, Argentina; 9.5% (95% CI: 8.2, 10.9) in Bariloche, Argentina; 18.1% (95% CI: 16.3, 20.0) in Temuco, Chile, and 18.2 (95% CI: 16.3, 20.2) in Pando-Barros Blancos, Uruguay. The multivariate model showed that, adjusted by location, being female, being between 35 and 44 years old, having experienced at least one stressful life event, currently smoking, and having a history of chronic medical diseases were independently associated with an increased risk of MDE, while having higher education and being married or living with a partner reduced the risk of MDE. These results are representative of the selected cities included in the study. As such extrapolation to the general populations of Argentina, Chile, and Uruguay should be done with caution CONCLUSIONS: This study showed a high prevalence and variability of MDE in the Southern Cone of Latin America. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Two new species of the Liolaemus elongatus-kriegi complex (Iguania, Liolaemidae) from Andean highlands of southern Chile

    PubMed Central

    Troncoso-Palacios, Jaime; Díaz, Hugo A.; Esquerré, Damien; Urra, Felix A.

    2015-01-01

    Abstract The elongatus-kriegi complex is one of the most diverse clades of the Liolaemus (sensu stricto) subgenus of lizards. There are currently 29 species recognized in this group distributed between Chile and Argentina. Based on molecular evidence, there seem to be five main clades nested within this complex: the elongatus, leopardinus, kriegi, petrophilus and punmahuida clades. Liolaemus buergeri and Liolaemus kriegi, both of the kriegi clade, were believed to inhabit the surroundings of the Laja Lagoon, in the Biobío Region of Chile. Moreover, this Chilean population of Liolaemus kriegi was recently recognized as an undescribed taxon called “Liolaemus sp. A” based on molecular phylogenetics. In this work, we studied these two populations of the Laja Lagoon and provided the morphological diagnosis to describe them as two new species: Liolaemus scorialis sp. n. and Liolaemus zabalai sp. n., previously considered Liolaemus buergeri and “Liolaemus kriegi/Liolaemus sp. A” respectively. Additionally, we identified another population of Liolaemus scorialis in the vicinity of La Mula Lagoon in the Araucanía Region of Chile. Liolaemus scorialis differs from almost all of the species of the elongatus-kriegi complex by its considerably smaller size. Nevertheless, without molecular data we cannot assign it to any particular subclade. Liolaemus zabalai belongs to the kriegi clade based on published molecular phylogenies. Finally, we provide some natural history data on both species and we document for the first time the presence of Liolaemus neuquensis in Chile from a museum specimen from La Mula Lagoon. PMID:25987873

  5. Assessment of Debris Flow Potential Hazardous Zones Using Numerical Models in the Mountain Foothills of Santiago, Chile

    NASA Astrophysics Data System (ADS)

    Celis, C.; Sepulveda, S. A.; Castruccio, A.; Lara, M.

    2017-12-01

    Debris and mudflows are some of the main geological hazards in the mountain foothills of Central Chile. The risk of flows triggered in the basins of ravines that drain the Andean frontal range into the capital city, Santiago, increases with time due to accelerated urban expansion. Susceptibility assessments were made by several authors to detect the main active ravines in the area. Macul and San Ramon ravines have a high to medium debris flow susceptibility, whereas Lo Cañas, Apoquindo and Las Vizcachas ravines have a medium to low debris flow susceptibility. This study emphasizes in delimiting the potential hazardous zones using the numerical simulation program RAMMS-Debris Flows with the Voellmy model approach, and the debris-flow model LAHARZ. This is carried out by back-calculating the frictional parameters in the depositional zone with a known event as the debris and mudflows in Macul and San Ramon ravines, on May 3rd, 1993, for the RAMMS approach. In the same scenario, we calibrate the coefficients to match conditions of the mountain foothills of Santiago for the LAHARZ model. We use the information obtained for every main ravine in the study area, mainly for the similarity in slopes and material transported. Simulations were made for the worst-case scenario, caused by the combination of intense rainfall storms, a high 0°C isotherm level and material availability in the basins where the flows are triggered. The results show that the runout distances are well simulated, therefore a debris-flow hazard map could be developed with these models. Correlation issues concerning the run-up, deposit thickness and transversal areas are reported. Hence, the models do not represent entirely the complexity of the phenomenon, but they are a reliable approximation for preliminary hazard maps.

  6. Late Pleistocene to Holocene tephrostratigraphy of the Lonquimay Volcano, South Central Chile

    NASA Astrophysics Data System (ADS)

    Gilbert, D.; Freundt, A.; Kutterolf, S.; Burkert, C.

    2010-12-01

    The Lonquimay Volcanic Complex (LVC) in South Central Chile (38.38°S, 71.58°W) is part of the Southern Volcanic Zone of the Andes, which formed in response to the subduction of the Nazca Plate beneath the South American Plate. During the course of its magmatic evolution, the LVC produced explosive eruptions documented in the succession of widespread tephra deposits, as well as large lava flows that originated from the main edifice and several adjacent minor eruptive centers. The last eruptive phase in Lonquimays volcanic evolution occurred from 1988-1990. It led to the formation of the Navidad cinder cone with its associated 10.2 km long lava flow, and a widely distributed tephra blanket of andesitic composition (Moreno and Gardeweg, 1989). During recent field work we reinvestigated and complemented the LVC tephrostratigraphy as originally established by Polanco (1998)by detailed logging of 22 outcrops and collecting 126 stratigraphically controlled samples that were analyzed for their matrix glass, mineral and bulk rock compositions. This data set allows us to verify and extend the field-based correlations, and to establish a tephrostratigraphy for the LVC that comprises 15 stratigraphic units (LQA-LQO) and provides a framework for ongoing investigations of the petrogenetic evolution of the LVC. The stratigraphic record identifies at least 13 explosive eruptions of VEI > 3 that occurred since the last glaciation period (17150 a BP, McCulloch et al. 2000). Magmatic compositions of the tephra deposits range from basaltic scoriae (51wt% SiO2) to evolved dacitic pumice lapilli layers (67wt% SiO2), and thus have a wider compositional range than the chemically distinct andesitic lavas (57-63wt%) of the LVC. The vertical succession of tephra compositions reflects four periods of progressive magmatic differentiation, each successively tapped by several eruptions. The maximum degree of fractionation reached during these periods increases to younger ages. The

  7. Zooplankton Responses to Low-Oxygen Condition upon a Shallow Oxygen Minimum Zone in the Upwelling Region off Chile

    NASA Astrophysics Data System (ADS)

    Hidalgo, P.; Escribano, R.

    2015-12-01

    A shallow oxygen minimum zone (OMZ) is a critical component in the coastal upwelling ecosystem off Chile. This OMZ causes oxygen-deficient water entering the photic layer and affecting plankton communities having low tolerance to hypoxia. Variable, and usually species-dependent, responses of zooplankton to hypoxia condition can be found. Most dominant species avoid hypoxia by restricting their vertical distribution, while others can temporarily enter and even spent part of their life cycle within the OMZ. Whatever the case, low-oxygen conditions appear to affect virtually all vital rates of zooplankton, such as mortality, fecundity, development and growth and metabolism, and early developmental stages seem more sensitive, with significant consequences for population and community dynamics. For most study cases, these effects are negative at individual and population levels. Observations and predictions upon increasing upwelling intensity over the last 20-30 years indicate a gradual shoaling of the OMZ, and so that an expected enhancement of these negative effects of hypoxia on the zooplankton community. Unknown processes of adaptation and community-structure adjustments are expected to take place with uncertain consequences for the food web of this highly productive eastern boundary current ecosystem.

  8. Isolation of Helicobacter pylori in gastric mucosa and susceptibility to five antimicrobial drugs in Southern chile

    PubMed Central

    Otth, Laura; Wilson, Myra; Fernández, Heriberto; Otth, Carola; Toledo, Claudio; Cárcamo, Victoria; Rivera, Paula; Ruiz, Luis

    2011-01-01

    Helicobacter pylori colonizes more than 50% of the world population thus, it is considered an important cause of gastric cancer. The aim of this study was to determine the isolation frequency of H. pylori in Southern Chile from patients with symptomatology compatible with gastritis or gastric ulcer and to correlate these findings with demographic parameters of infected patients and the susceptibility profiles of the isolated strains to the antimicrobial drugs used in the eradication treatments. A total of 240 patients were enrolled in the study. Each gastric biopsy was homogenized and seeded onto blood agar plates containing a selective antibiotics mixture (DENT supplement). Plates were incubated at 37° C in a microaerophilic environment for five days. The susceptibility profiles to amoxicillin, ciprofloxacin, clarithromycin, tetracycline and metronidazole were determined using the E-test method. H. pylori was isolated from 99 patients (41.3%) with slightly higher frequency in female (42% positive cultures) than male (40.2% positive cultures). With regard to age and educational level, the highest isolation frequencies were obtained in patients between 21–30 (55%) and 41–50 (52.6%) years old, and patients with secondary (43.9%) and university (46.2%) educational levels. Nineteen (21.6%) strains showed resistance to at least one antimicrobial drug. Tetracycline was the most active antimicrobial in vitro, whereas metronidazole was the less active. One strain (5.3%) showed resistance to amoxicillin, clarithomycin and metronidazole, simultaneously. PMID:24031652

  9. Something fishy: Chile's blue revolution, commodity diseases, and the problem of sustainability.

    PubMed

    Soluri, John

    2011-01-01

    The United Nations describes aquaculture as the fastest-growing method of food production, and some industry boosters have heralded the coming of a sustainable blue revolution. This article interprets the meteoric rise and sudden collapse of Atlantic salmon aquaculture in southern Chile (1980-2010) by integrating concepts from commodity studies and comparative environmental history. I juxtapose salmon aquaculture to twentieth-century export banana production to reveal the similar dynamics that give rise to "commodity diseases"—events caused by the entanglement of biological, social, and political-economic processes that operate on local, regional, and transoceanic geographical scales. Unsurprisingly, the risks and burdens associated with commodity diseases are borne disproportionately by production workers and residents in localities where commodity disease events occur. Chile's blue revolution suggests that evaluating the sustainability of aquaculture in Latin America cannot be divorced from processes of accumulation.

  10. Evolution of Late Miocene to Contemporary Displacement Transfer Between the Northern Furnace Creek and Southern Fish Lake Valley Fault Zones and the Central Walker Lane, Western Great Basin, Nevada

    NASA Astrophysics Data System (ADS)

    Oldow, J. S.; Geissman, J. W.

    2013-12-01

    Late Miocene to contemporary displacement transfer from the north Furnace Creek (FCF) and southern Fish Lake Valley (FLVF) faults to structures in the central Walker Lane was and continues to be accommodated by a belt of WNW-striking left-oblique fault zones in the northern part of the southern Walker Lane. The WNW fault zones are 2-9 km wide belts of anastomosing fault strands that intersect the NNW-striking FCF and southern FLVF in northern Death Valley and southern Fish Lake Valley, respectively. The WNW fault zones extend east for over 60 km where they merge with a 5-10 km wide belt of N10W striking faults that marks the eastern boundary of the southern Walker Lane. Left-oblique displacement on WNW faults progressively decreases to the east, as motion is successively transferred northeast on NNE-striking faults. NNE faults localize and internally deform extensional basins that each record cumulative net vertical displacements of between 3.0 and 5.2 km. The transcurrent faults and associated basins decrease in age from south to north. In the south, the WNW Sylvania Mountain fault system initiated left-oblique motion after 7 Ma but does not have evidence of contemporary displacement. Farther north, the left-oblique motion on the Palmetto Mountain fault system initiated after 6.0 to 4.0 Ma and has well-developed scarps in Quaternary deposits. Cumulative left-lateral displacement for the Sylvania Mountain fault system is 10-15 km, and is 8-12 km for the Palmetto fault system. The NNE-striking faults that emanate from the left-oblique faults merge with NNW transcurrent faults farther north in the eastern part of the Mina deflection, which links the Owens Valley fault of eastern California to the central Walker Lane. Left-oblique displacement on the Sylvania Mountain and Palmetto Mountain fault zones deformed the Furnace Creek and Fish Lake Valley faults. Left-oblique motion on Sylvania Mountain fault deflected the FCF into the 15 km wide Cucomungo Canyon restraining

  11. Mineral chemistry of isotropic gabbros from the Manamedu Ophiolite Complex, Cauvery Suture Zone, southern India: Evidence for neoproterozoic suprasubduction zone tectonics

    NASA Astrophysics Data System (ADS)

    Yellappa, T.; Tsunogae, T.; Chetty, T. R. K.; Santosh, M.

    2016-11-01

    The dismembered units of the Neoproterozoic Manamedu Ophiolite Complex (MOC) in the Cauvery Suture Zone, southern India comprises a well preserved ophiolitic sequence of ultramafic cumulates of altered dunites, pyroxenites, mafic cumulates of gabbros, gabbro-norites and anorthosites in association with plagiogranites, isotropic gabbros, metadolerites, metabasalts/amphibolites and thin layers of ferruginous chert bands. The isotropic gabbros occur as intrusions in association with gabbroic anorthosites, plagiogranite and metabasalts/amphibolites. The gabbros are medium to fine grained with euhedral to subhedral orthopyroxenes, clinopyroxenes and subhedral plagioclase, together with rare amphiboles. Mineral chemistry of isotropic gabbros reveal that the clinopyroxenes are diopsidic to augitic in composition within the compositional ranges of En(42-59), Fs(5-12), Wo(31-50). They are Ca-rich and Na poor (Na2O < 0.77 wt%) characterized by high-Mg (Mg# 79-86) and low-Ti (TiO2 < 0.35 wt%) contents. The tectonic discrimination plots of clinopyroxene data indicate island arc signature of the source magma. Our study further confirms the suprasubduction zone origin of the Manamedu ophiolitic suite, associated with the subduction-collision history of the Neoproterozoic Mozambique ocean during the assembly of Gondwana supercontinent.

  12. Shear zones bounding the central zone of the Limpopo Mobile Belt, southern Africa

    NASA Astrophysics Data System (ADS)

    McCouri, Stephen; Vearncombe, Julian R.

    Contrary to previously suggested north-directed thrust emplacement of the central zone of the Limpopo mobile belt, we present evidence indicating west-directed emplacement. The central zone differs from the marginal zones in rock types, structural style and isotopic signature and is an allochthonous thrust sheet. It is bounded in the north by the dextral Tuli-Sabi shear zone and in the south by the sinistral Palala shear zone which are crustal-scale lateral ramps. Published gravity data suggest that the lateral ramps are linked at depth and they probably link at the surface, in a convex westward frontal ramp, in the vicinity of longitude 26°30'E in eastern Botswana. Two phases of movement, the first between 2.7 and 2.6 Ga and the second between 2.0 and 1.8 Ga. occurred on both the Tuli-Sabi and the Palala shear zones.

  13. Foreshock Patterns Preceding Great Earthquakes in the Subduction Zone of Chile

    NASA Astrophysics Data System (ADS)

    Papadopoulos, G. A.; Minadakis, G.

    2016-10-01

    Foreshock activity is considered as one of the most promising precursory changes for the main shock prediction in the short term. Averaging over several foreshock sequences has shown that foreshocks are characterized by distinct 3D patterns: their epicenters move towards the main shock epicenter, event count accelerates, and b-value drops. However, these space-time-size patterns were verified so far only in a very few individual cases mainly due to inadequate seismicity catalogue data. We have investigated 3D foreshock patterns before the M w 8.8 Maule in 27 February 2010, M w 8.1 Iquique in 1 April 2014, and M w 8.4 Illapel in 16 September 2015 great earthquakes in the Chile subduction zone. To avoid biased results, no a priori spatiotemporal definitions of foreshocks were inserted. The procedure was based on pattern recognition from statistically significant seismicity changes in the three domains. The pattern recognition in one domain was independent of the pattern recognition in another domain. We found and verified with two independent catalogue data sets (CSN, IPOC) that within a critical area of ca. 65 km from the main shock epicenter, the 2014 event was preceded by distinct foreshock 3D patterns. A nearly weak foreshock stage (20 January-14 March 2014) was followed by a main-strong stage (15 March-1 April 2014) highly significant in all domains, although foreshock activity slightly decreased in about the last 5 days. Seismic moment release also accelerated in the last stage due to the occurrence of a cluster of very strong foreshock events. Foreshock activity very likely occurred in the hanging-wall fault domain on the South American Plate overriding Nazca Plate. The 2014 foreshock activity was quite similar to the one preceding the 6 Apr. 2009 L' Aquila (Italy) M w 6.3 earthquake associated with normal faulting. Using the 2014 earthquake as a reference event, we observed that similar foreshock 3D patterns preceded the 2010 and 2015 earthquakes within

  14. Observing the Greatest Earthquakes: AGU Chapman Conference on Giant Earthquakes and Their Tsunamis: Viña del Mar and Valparaíso, Chile, 16–20 May 2010

    USGS Publications Warehouse

    Atwater, Brian F.; Barrientos, Sergio; Cifuentes, Inés; Cisternas, Marco; Wang, Kelin

    2010-01-01

    An AGU Chapman Conference commemorated the fiftieth anniversary of the 1960 M 9.5 Chile earthquake. Participants reexamined this earthquake, the largest ever recorded instrumentally, and compared it with Chile's February 2010 M 8.8 earthquake. They also addressed the giant earthquake potential of subduction zones worldwide and strategies for reducing losses due to tsunamis. The conference drew 96 participants from 18 countries, and it reached out to public audiences in Chile.

  15. Design of a Teacher Professional Development Program for International Collaborative Astronomy Research in Chile

    NASA Astrophysics Data System (ADS)

    Pompea, S. M.; Seguel, J.; Sparks, R.; Opazo, L.; Walker, C. E.

    2011-12-01

    We have designed (but not yet implemented) a program where five US teachers will team with five Chilean teachers to conduct high-quality astronomical research in Chile that can be brought back to their classrooms and shared with their students. This project will introduce US teachers to four research projects at the Observatorio Cruz del Sur, one the largest municipal observatories in South America. The program would operate over the course of a year or more, with a month of observing and conducting research in Chile. The observatory is located in the small town of Combarbalá (Limari Province, IV Región de Coquimbo) in a region rich in archeological, historical, and cultural heritage. Teachers will use high-sensitivity digital detectors to take data through telescopes and with cameras as part of four research projects- light pollution research, digital photography of dark large areas of the sky using wide angle cameras, asteroid photometry, and exoplanet photometric studies. The project partners the National Optical Astronomy Observatory (Tucson, Arizona and La Serena, Chile), the Municipality of the town of Combarbalá, the National Observatory of Chile/University of Chile, and REUNA, an internet communication alliance that serves Chilean universities and observatories. Since the US teachers will have their astronomy classes running while they are in Chile, the teachers will be communicating with their classes on a regular basis. The teachers will also be providing long-term access to southern sky data for other teachers and students in the US while establishing the basis for long-term collaborative research. We expect the program to establish long-term international research collaborations among US and Chilean teachers and students.

  16. A low-temperature ductile shear zone: The gypsum-dominated western extension of the brittle Fella-Sava Fault, Southern Alps.

    PubMed

    Bartel, Esther Maria; Neubauer, Franz; Heberer, Bianca; Genser, Johann

    2014-12-01

    Based on structural and fabric analyses at variable scales we investigate the evaporitic gypsum-dominated Comeglians-Paularo shear zone in the Southern Alps (Friuli). It represents the lateral western termination of the brittle Fella-Sava Fault. Missing dehydration products of gypsum and the lack of annealing indicate temperatures below 100 °C during development of the shear zone. Despite of such low temperatures the shear zone clearly exhibits mylonitic flow, thus evidencing laterally coeval activity of brittle and viscous deformation. The dominant structures within the gypsum rocks of the Lower Bellerophon Formation are a steeply to gently S-dipping foliation, a subhorizontal stretching lineation and pure shear-dominated porphyroclast systems. A subordinate simple shear component with dextral displacement is indicated by scattered σ-clasts. Both meso- and microscale structures are characteristic of a subsimple shear type of deformation with components of both coaxial and non-coaxial strain. Shortening in a transpressive regime was accommodated by right-lateral displacement and internal pure shear deformation within the Comeglians-Paularo shear zone. The shear zone shows evidence for a combination of two stretching faults, where stretching occurred in the rheologically weaker gypsum member and brittle behavior in enveloping lithologies.

  17. INFLUENCE OF DIFFERENT WATER MASSES AND BIOLOGICAL ACTIVITY ON DIMETHYLSULPHIDE AND DIMETHYLSULPHONIOPROPIONATE IN THE SUBANTARCTIC ZONE OF THE SOUTHERN OCEAN DURING ACE-1

    EPA Science Inventory

    Measurements of salinity, temperature, phytoplankton biomass and speciation, dissolved nitrate, dimethylsulphide (DMS) in seawater and air, and dimethylsulphoniopropionate (DMSP), were made in the subantarctic zone of the Southern Ocean from 40|-54|S, and 140|-153|E during the So...

  18. The mosses (Bryophyta) of Capitán Prat Province, Aisén Region, southern Chile.

    PubMed

    Larraín, Juan

    2016-01-01

    The bryophytes of Capitán Prat province have remained one of the least explored in Chile. The eventual construction of several dams on the rivers Baker and Pascua required prospection of all groups of organisms including bryophytes, work that was facilitated by the recent construction of vehicular roads that now offer easy access to previously almost unaccessible locations. The results of intense bryophyte collecting during the austral summer of 2007 are here presented. A total of 260 moss taxa are reported for the province, corresponding to 256 species and four infraspecific taxa, of which 211 are new records for the province, 54 are new for Aisén Region, and two are new records for continental Chile ( Pohlia longicollis (Hedw.) Lindb. and Rigodium toxarion var. robustum (Broth.) Zomlefer). Twelve species extend their known distribution ranges to the north, whereas 49 extend them to the south.

  19. The mosses (Bryophyta) of Capitán Prat Province, Aisén Region, southern Chile

    PubMed Central

    Larraín, Juan

    2016-01-01

    Abstract The bryophytes of Capitán Prat province have remained one of the least explored in Chile. The eventual construction of several dams on the rivers Baker and Pascua required prospection of all groups of organisms including bryophytes, work that was facilitated by the recent construction of vehicular roads that now offer easy access to previously almost unaccessible locations. The results of intense bryophyte collecting during the austral summer of 2007 are here presented. A total of 260 moss taxa are reported for the province, corresponding to 256 species and four infraspecific taxa, of which 211 are new records for the province, 54 are new for Aisén Region, and two are new records for continental Chile (Pohlia longicollis (Hedw.) Lindb. and Rigodium toxarion var. robustum (Broth.) Zomlefer). Twelve species extend their known distribution ranges to the north, whereas 49 extend them to the south. PMID:27698577

  20. Anammox bacteria and the anaerobic oxidation of ammonium in the oxygen minimum zone off northern Chile

    NASA Astrophysics Data System (ADS)

    Galán, Alexander; Molina, Verónica; Thamdrup, Bo; Woebken, Dagmar; Lavik, Gaute; Kuypers, Marcel M. M.; Ulloa, Osvaldo

    2009-07-01

    Anammox is the anaerobic oxidation of ammonium by nitrite or nitrate to yield N 2. This process, along with conventional denitrification, contributes to nitrogen loss in oxygen-deficient systems. Anammox is performed by a special group of bacteria belonging to the Planctomycetes phylum. However, information about the distribution, activity, and controlling factors of these anammox bacteria is still limited. Herein, we examine the phylogenetic diversity, vertical distribution, and activity of anammox bacteria in the coastal upwelling region and oxygen minimum zone off northern Chile. The phylogeny of anammox bacteria was studied using primers designed to specifically target 16S rRNA genes from Planctomycetes in samples taken during a cruise in 2004. Anammox bacteria-like sequences affiliated with Candidatus "Scalindua spp." dominated the 16S rRNA gene clone library. However, 62% of the sequences subgrouped separately within this cluster and together with a single sequence retrieved from the suboxic zone of the freshwater Lake Tanganyika. The vertical distribution and activity of anammox bacteria were explored through CARD-FISH (fluorescence in situ hybridization with catalyzed reporter deposition) and 15N labeling incubations, respectively, at two different open-ocean stations during a second cruise in 2005. Anammox bacterial CARD-FISH counts (up to 3000 cells ml -1) and activity (up to 5.75 nmol N 2 L -1 d -1) were only detected at the station subjected directly to the upwelling influence. Anammox cell abundance and activity were highest at 50 m depth, which is the upper part of the OMZ. In this layer, a high abundance of cyanobacteria and a marked nitrogen deficit were also observed. Thus, our results show the presence of a new subcluster within the marine anammox phylogeny and indicate high vertical variability in the abundance and activity of anammox bacteria that could be related to an intensification of carbon and nitrogen cycling in the upper part of the OMZ.

  1. Urban dogs in rural areas: Human-mediated movement defines dog populations in southern Chile.

    PubMed

    Villatoro, Federico J; Sepúlveda, Maximiliano A; Stowhas, Paulina; Silva-Rodríguez, Eduardo A

    2016-12-01

    Management strategies for dog populations and their diseases include reproductive control, euthanasia and vaccination, among others. However, the effectiveness of these strategies can be severely affected by human-mediated dog movement. If immigration is important, then the location of origin of dogs imported by humans will be fundamental to define the spatial scales over which population management and research should apply. In this context, the main objective of our study was to determine the spatial extent of dog demographic processes in rural areas and the proportion of dogs that could be labeled as immigrants at multiple spatial scales. To address our objective we conducted surveys in households located in a rural landscape in southern Chile. Interviews allowed us to obtain information on the demographic characteristics of dogs in these rural settings, human influence on dog mortality and births, the localities of origin of dogs living in rural areas, and the spatial extent of human-mediated dog movement. We found that most rural dogs (64.1%) were either urban dogs that had been brought to rural areas (40.0%), or adopted dogs that had been previously abandoned in rural roads (24.1%). Some dogs were brought from areas located as far as ∼700km away from the study area. Human-mediated movement of dogs, especially from urban areas, seems to play a fundamental role in the population dynamics of dogs in rural areas. Consequently, local scale efforts to manage dog populations or their diseases are unlikely to succeed if implemented in isolation, simply because dogs can be brought from surrounding urban areas or even distant locations. We suggest that efforts to manage or study dog populations and related diseases should be implemented using a multi-scale approach. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Isolating active orogenic wedge deformation in the southern Subandes of Bolivia

    NASA Astrophysics Data System (ADS)

    Weiss, Jonathan R.; Brooks, Benjamin A.; Foster, James H.; Bevis, Michael; Echalar, Arturo; Caccamise, Dana; Heck, Jacob; Kendrick, Eric; Ahlgren, Kevin; Raleigh, David; Smalley, Robert; Vergani, Gustavo

    2016-08-01

    A new GPS-derived surface velocity field for the central Andean backarc permits an assessment of orogenic wedge deformation across the southern Subandes of Bolivia, where recent studies suggest that great earthquakes (>Mw 8) are possible. We find that the backarc is not isolated from the main plate boundary seismic cycle. Rather, signals from subduction zone earthquakes contaminate the velocity field at distances greater than 800 km from the Chile trench. Two new wedge-crossing velocity profiles, corrected for seasonal and earthquake affects, reveal distinct regions that reflect (1) locking of the main plate boundary across the high Andes, (2) the location of and loading rate at the back of orogenic wedge, and (3) an east flank velocity gradient indicative of décollement locking beneath the Subandes. Modeling of the Subandean portions of the profiles indicates along-strike variations in the décollement locked width (WL) and wedge loading rate; the northern wedge décollement has a WL of ~100 km while accumulating slip at a rate of ~14 mm/yr, whereas the southern wedge has a WL of ~61 km and a slip rate of ~7 mm/yr. When compared to Quaternary estimates of geologic shortening and evidence for Holocene internal wedge deformation, the new GPS-derived wedge loading rates may indicate that the southern wedge is experiencing a phase of thickening via reactivation of preexisting internal structures. In contrast, we suspect that the northern wedge is undergoing an accretion or widening phase primarily via slip on relatively young thrust-front faults.

  3. Farm-level reproduction number during an epidemic of infectious salmon anemia virus in southern Chile in 2007-2009.

    PubMed

    Mardones, F O; Perez, A M; Valdes-Donoso, P; Carpenter, T E

    2011-12-01

    An epidemic of infectious salmon anemia virus (ISAV) has greatly impacted salmon production in Chile with devastating social and economic consequences. The epidemic is analyzed here and is likely the largest ISAV outbreak reported affecting one of the most productive regions for salmon farming activities in the world. After re-emerging in 2007, ISAV rapidly expanded the following two years, both in magnitude and geographic range, affecting about 65% and 50% of salmon farms located at the 10th and 11th regions of Chile, respectively. A useful metric for the control of infectious diseases that quantifies the progression of an epidemic is the reproduction number at the farm level (R(f)), which describes the mean number of secondary cases generated by an infectious farm. The parameter in this study was estimated for individual farms (R(fi)), specific phases (R(tf)), and for the entire epidemic (R(f)) by using several analytical approaches based on the characterization of the epidemic curves for the two regions. For the initial spread and the epidemic growth phase, initial and intrinsic growth rates were used to estimate R(tf). In addition, two approaches (epidemic final size and nearest neighbor analyses) were used to obtain an individual (R(fi)) and overall estimate of R(f) for the complete epidemic. In general, two distinct regional patterns of spread were identified. In the 10th region, after an explosive initial spread of ISAV in which R(tf) reached 12.0-16.9, a smaller epidemic growth of 1.6≤R(tf)≥2.5 and a final burnout with R(tf)<1 were observed. For the 11th region, R(tf) only reached 2.4 during the initial spread phase, ranged from 1.6≤R(tf)≥4.4 during the epidemic growth phases and ended when R(tf) was <1.0. The epidemic was characterized by clustering of ISAV 'superspreaders' farms i.e., farms with statistically significantly (P<0.047) higher R(fi) values. Distances between pairs of infected farms were statistically significantly (P=0.003) shorter in

  4. Astro Chile | CTIO

    Science.gov Websites

    Program PIA Program GO-FAAR Program Other Opportunities Tourism Visits to Tololo Astro tourism in Chile Tourism in Chile Information for travelers Visit Tololo Media Relations News Press Release Publications

  5. Twin Convergence Zones

    NASA Technical Reports Server (NTRS)

    2002-01-01

    NASA's QuikSCAT satellite has confirmed a 30-year old largely unproven theory that there are two areas near the equator where the winds converge year after year and drive ocean circulation south of the equator. By analyzing winds, QuikSCAT has found a year-round southern and northern Intertropical Convergence Zone. This find is important to climate modelers and weather forecasters because it provides more detail on how the oceans and atmosphere interact near the equator. The Intertropical Convergence Zone (ITCZ) is the region that circles the Earth near the equator, where the trade winds of both the Northern and Southern Hemispheres come together. North of the equator, strong sun and warm water of the equator heats the air in the ITCZ, drawing air in from north and south and causing the air to rise. As the air rises it cools, releasing the accumulated moisture in an almost perpetual series of thunderstorms. Satellite data, however, has confirmed that there is an ITCZ north of the equator and a parallel ITCZ south of the equator. Variation in the location of the ITCZ is important to people around the world because it affects the north-south atmospheric circulation, which redistributes energy. It drastically affects rainfall in many equatorial nations, resulting in the wet and dry seasons of the tropics rather than the cold and warm seasons of higher latitudes. Longer term changes in the ITCZ can result in severe droughts or flooding in nearby areas. 'The double ITCZ is usually only identified in the Pacific and Atlantic Oceans on a limited and seasonal basis,' said Timothy Liu, of NASA's Jet Propulsion Laboratory and California Institute of Technology, Pasadena, Calif., and lead researcher on the project. In the eastern Pacific Ocean, the southern ITCZ is usually seen springtime. In the western Atlantic Ocean, the southern ITCZ was recently clearly identified only in the summertime. However, QuikSCAT's wind data has seen the southern ITCZ in all seasons across the

  6. [Length of lactational amenorrhea in an urban population of Temuco, Chile].

    PubMed

    Valdés, Patricio; Sierralta, Pablo; Ossa, Ximena; Barría, Angélica

    2002-01-01

    Studies done in Santiago, Chile show that menses return before the sixth month of puerperium in 50% of lactating women, even in those that continue with exclusive breast feeding. To study the length of lactational amenorrhea in a group of women living in Southern Chile. One hundred fourteen women giving exclusive breast feeding, were followed from the third postpartum month, to determine the length of lactational amenorrhea. Its relationship with general characteristics of the mothers and children and breast feeding pattern was also studied. Sixty six women (58%) recovered their menses before the 6th postpartum month and their length of lactational amenorrhea was 101 +/- 5 days. In the rest of the sample, the length was 277 +/- 10 days. No differences in characteristics of the mothers and children or breast feeding pattern, were observed between these two groups. A short lactational amenorrhea is common in the Chilean population. Clinical characteristics or pattern of breast feeding do not explain the length of LA in this population.

  7. The Ongoing 2011 Eruption of Cordón Caulle (Southern Andes) and its Related Hazards

    NASA Astrophysics Data System (ADS)

    Amigo, A.; Lara, L. E.; Silva, C.; Orozco, G.; Bertin, D.

    2011-12-01

    On June 4, 2011, at 18:45 UTC, Cordón Caulle volcano (Southern Andes, 40.52S, 72.14W) erupted explosively after 51 years of quiescence. The last eruption occurred in 1960 and was triggered by the great Mw 9.5 Chile earthquake. The ongoing eruption started after 2 months of increased shallow seismicity as recorded by OVDAS (the volcano observatory at Sernageomin). This close monitoring effort allowed a timely eruption forecast with at least 3 hours of warning, which facilitated the crisis response. In addition to this successful performance, for the first time in Chile volcanic hazards were assessed in advance supporting the emergency management. In particular, tephra dispersal was daily forecasted using the ASHFALL advection-diffusion model and potential lahars and PDC impact zones were delineated according to numerical approaches. The first eruptive stage lasted 27 hours. It was characterized by ca. 15-km strong Plinian-like column, associated with the emission of 0.2 - 0.4 km3 of magma (DRE). Tephra fallout mostly occurred in Chile and Argentina, although fine particles and aerosols circumnavigated the globe twice, causing disruptions on air navigation across the Southern Hemisphere. The second ongoing eruptive stage has been characterized by persistent weak plumes and lava emission at effusion rates in the range of 20 and 60 m3/s, which total volume is estimated <0.20 km3 (at the end of July 2011). Eruptive products have virtually the same bulk composition as those of the historical 1921 and 1960 eruptions, corresponding to phenocryst-poor rhyodacites (67 - 70% SiO2) for what a pre-eruptive temperature of ca. 920C could be inferred. In contrast to the previous eruptive cycles, the ongoing eruption has not evolved (at the time of writing) as a fissure eruption although the vent is atop of fault scarp that borders the Pleistocene-Holocene extensional graben of the Cordón Caulle. This episode is a good case of successful eruption forecast and hazards assessment

  8. Continuing megathrust earthquake potential in Chile after the 2014 Iquique earthquake

    USGS Publications Warehouse

    Hayes, Gavin P.; Herman, Matthew W.; Barnhart, William D.; Furlong, Kevin P.; Riquelme, Sebástian; Benz, Harley M.; Bergman, Eric; Barrientos, Sergio; Earle, Paul S.; Samsonov, Sergey

    2014-01-01

    The seismic gap theory identifies regions of elevated hazard based on a lack of recent seismicity in comparison with other portions of a fault. It has successfully explained past earthquakes (see, for example, ref. 2) and is useful for qualitatively describing where large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile which had not ruptured in a megathrust earthquake since a M ~8.8 event in 1877. On 1 April 2014 a M 8.2 earthquake occurred within this seismic gap. Here we present an assessment of the seismotectonics of the March–April 2014 Iquique sequence, including analyses of earthquake relocations, moment tensors, finite fault models, moment deficit calculations and cumulative Coulomb stress transfer. This ensemble of information allows us to place the sequence within the context of regional seismicity and to identify areas of remaining and/or elevated hazard. Our results constrain the size and spatial extent of rupture, and indicate that this was not the earthquake that had been anticipated. Significant sections of the northern Chile subduction zone have not ruptured in almost 150 years, so it is likely that future megathrust earthquakes will occur to the south and potentially to the north of the 2014 Iquique sequence.

  9. Continuing megathrust earthquake potential in Chile after the 2014 Iquique earthquake.

    PubMed

    Hayes, Gavin P; Herman, Matthew W; Barnhart, William D; Furlong, Kevin P; Riquelme, Sebástian; Benz, Harley M; Bergman, Eric; Barrientos, Sergio; Earle, Paul S; Samsonov, Sergey

    2014-08-21

    The seismic gap theory identifies regions of elevated hazard based on a lack of recent seismicity in comparison with other portions of a fault. It has successfully explained past earthquakes (see, for example, ref. 2) and is useful for qualitatively describing where large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile, which had not ruptured in a megathrust earthquake since a M ∼8.8 event in 1877. On 1 April 2014 a M 8.2 earthquake occurred within this seismic gap. Here we present an assessment of the seismotectonics of the March-April 2014 Iquique sequence, including analyses of earthquake relocations, moment tensors, finite fault models, moment deficit calculations and cumulative Coulomb stress transfer. This ensemble of information allows us to place the sequence within the context of regional seismicity and to identify areas of remaining and/or elevated hazard. Our results constrain the size and spatial extent of rupture, and indicate that this was not the earthquake that had been anticipated. Significant sections of the northern Chile subduction zone have not ruptured in almost 150 years, so it is likely that future megathrust earthquakes will occur to the south and potentially to the north of the 2014 Iquique sequence.

  10. Morphology of Southern Hemisphere Riometer Auroral Absorption

    DTIC Science & Technology

    2006-06-01

    Departamento de Geofísica Universidad de Concepción, Concepción CHILE foppiano@udec.cl ABSTRACT A morphology of riometer auroral absorption is...PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Departamento de Geofísica Universidad de ...range of frequencies used an inverse -square frequency dependence approximately holds. Morphology of Southern Hemisphere Riometer Auroral Absorption

  11. Estimates of Abundance and Trend of Chilean Blue Whales off Isla de Chiloé, Chile

    PubMed Central

    Cabrera, Elsa; Carlson, Carole A.; Brownell, Robert L.

    2017-01-01

    Since 1970, blue whales (Balaenoptera musculus) have been seen feeding in the waters off southern Chile during the summer and autumn (December to May). Investigation of the genetic, acoustic and morphological characteristics of these blue whales shows that they are a distinct but unnamed subspecies, called the Chilean blue whales. Photo-identification surveys have been conducted in the waters off northwestern Isla Grande de Chiloé, southern Chile from 2004–2012 and Isla Chañaral, central Chile in 2012. Over this time, 1,070 blue whales were encountered yielding, after photo-quality control, 318 and 267 unique photographs of the left and right side of the flank respectively. Using mark-recapture analysis of left and right side photographs collected from Isla Grande de Chiloé (2004–2012), open population models estimate that ~570–760 whales are feeding seasonally in this region. POPAN superpopulation abundance estimates for the same feeding ground in 2012 are 762 (95% confidence intervals, CI = 638–933) and 570 (95% CI 475–705) for left and right side datasets respectively, very similar to results from closed population models. Estimates of trend revealed strong variation in abundance, peaking in 2009 and [suggesting] fluctuating use in the survey area over time, likely related to the density of their prey. High inter-annual return rates suggest a degree of site-fidelity of individuals to Isla Grande de Chiloé and that the number of whales using this feeding ground is relatively small. PMID:28081160

  12. Preliminary Results From the Chile-Illapel Aftershock Experiment (CHILLAX)

    NASA Astrophysics Data System (ADS)

    Roecker, S. W.; Russo, R. M.; Comte, D.; Carrizo, D.; Peyrat, S.; Opazo, T.; Peña, G.; Farrell, M. E.; Moore, J.; Glick, R.; Rodriguez, E. E.

    2016-12-01

    On September 16, 2015, the Mw 8.3 Illapel earthquake ruptured a segment of the Nazca-South America subduction zone directly to the north of the 2010 Maule Mw 8.8 earthquake. Soon afterwards, a team from the Departamento de Geofisica, University of Chile, installed 18 short period sensors on land above the rupture to record aftershocks. A month later, the network was upgraded and expanded with funding from NSF RAPID to 20 broad band stations, loaned by IRIS PASSCAL. The installation of the Chile-Illapel Aftershock Experiment (CHILLAX) was completed in mid-November, 2015, and will operate until November, 2016. Preliminary analysis of data collected to date indicates an average detection rate of about 1000 locatable aftershocks per month. The combined CHILLAX and Maule aftershock deployments will yield the first modern-instrumentation observations of the zone of along-strike rupture termination that separates these temporally related and spatially adjacent megathrust rupture zones. Additionally, seismic observations of this part of the Nazca subduction zone are relatively sparse, and an aftershock sequence provides an opportunity to fill this gap efficiently. Preliminary analysis of CHILLAX network data revealed unexpected patterns in seismicity down dip from the rupture zone, in the unusual "flat slab" region to the east. Compared to the Maule event, the Illapel rupture apparently generated a more significant increase in seismicity in the 60-200 km depth range, suggesting that it "lit up" the subducted Nazca plate. Although high strain rates due to rupture might extend brittle failure into normally ductile regions, such an effect at these depths by the relatively low magnitude Illapel event is unusual. A perhaps more intriguing result is the frequent occurrence of events at depths significantly below that of the "flat slab". Attribution of this apparent second, deeper slab segment to event mislocations would require unrealistic seismic heterogeneity, We hypothesize

  13. Knowledge, attitudes, and practices regarding hantavirus disease and acceptance of a vaccine trial in rural communities of southern Chile.

    PubMed

    Valdivieso, Francisca; Gonzalez, Claudia; Najera, Manuel; Olea, Andrea; Cuiza, Analia; Aguilera, Ximena; Mertz, Gregory

    2017-04-03

    Andes hantavirus cardiopulmonary syndrome, transmitted by Oligoryzomys longicaudatus, has no approved treatment, a case fatality rate of 35%, and documented person-to-person transmission. An Andes vaccine, highly needed for prevention, is in development. We aimed to evaluate knowledge, attitudes and practices (KAP) regarding hantavirus disease and willingness to participate in a future Andes vaccine trials through a cross sectional face-to-face oral survey of a randomly selected adult sample from 2 rural communes in southern Chile. Human subjects approval was obtained from our institutional IRBs, and participants signed informed consent. We enrolled 319 subjects from Corral and 321 from Curarrehue; 98% had heard about hantavirus disease and its reservoir but only half knew about transmission, symptoms and prevention. Participants fear the disease but are only partially aware of their own risk. One third of participants reported presence of rodents inside their homes. Despite moderate confidence in their health system, most subjects perceived vaccines as beneficial, and 93% would accept an approved hantavirus vaccine. Half would agree to participate in a vaccine trial and 29% would allow their children to participate. Motivations to participate were mainly altruistic, while risk perception was the main reason for declining. Knowledge about hantavirus disease and prevention practices require reinforcement, and a vaccine trial seems feasible in these populations.

  14. Deep Tectonic Tremor in Haiti triggered by the 2010/02/27 Mw8.8 Maule, Chile earthquake

    NASA Astrophysics Data System (ADS)

    Aiken, C.; Peng, Z.; Douilly, R.; Calais, E.; Deschamps, A.; Haase, J. S.

    2013-05-01

    Tectonic tremors have been observed along major plate-boundary faults around the world. In most of these regions, tremors occur spontaneously (i.e. ambient) or as a result of small stress perturbations from passing surface waves (i.e. triggered). Because tremors are located below the seismogenic zone, a detailed study of their behavior could help to better understand how tectonic movement is accommodated in the deep root of major faults, and the relationship with large earthquakes. Here, we present evidence of triggered tremor in southern Haiti around the aftershock zone of the 2010/01/12 Mw7.0 Haiti earthquake. Following the January mainshock, several groups have installed land and ocean bottom seismometers to record aftershock activity (e.g., De Lepinay et al., 2011). In the following month, the 2010/02/27 Mw8.8 Maule, Chile earthquake occurred and was recorded in the southern Haiti region by these seismic stations. We apply a 5-15 Hz band-pass filter to all seismograms to identify local high-frequency signals during the Chile teleseismic waves. Tremor is identified as non-impulsive bursts with 10-20 s durations that is coherent among different stations and is modulated by surface waves. We also convert the seismic data into audible sounds and use them to distinguish between local aftershocks and deep tremor. We locate the source of the tremor bursts using an envelope cross-correlation method based on travel time differences. Because tremor depth is not well constrained with this method, we set it to 20 km, close to the recent estimate of Moho depth in this region (McNamara et al., 2012). Most tremors are located south of the surface expression of the Enriquillo-Plantain Garden Fault (EPGF), a high-angle southward dipping left-lateral strike-slip fault that marks the boundary between the Gonave microplate and the Caribbean plate, although the location errors are large. Tremor peaks are mostly modulated by Love wave velocity, which is consistent with left

  15. Project Hi-CLIMB: A Synoptic View of the Himalayan Collision Zone and Southern Tibet

    NASA Astrophysics Data System (ADS)

    Nábělek, J. L.; Vergne, J.; Hetenyi, G.

    2005-12-01

    Project Hi-CLIMB is a broadband seismic experiment whose goal is to produce a high-resolution continuous profile across the Himalaya and southern Tibet. The centerpiece of the project is a closely spaced, linear array of broadband seismographs, extending from the Ganga lowland, across the Himalayas, and onto the central Tibetan plateau. A complementary array of sparsely spaced stations flanks the linear array. Over 270 sites were occupied during the experiment. The principal institutions involved in the field operations were the Oregon State U. and U. of Illinois (USA), Dept. of Mines and Geology (Nepal), Chinese Academy of Geol. Sci. and Peking U. (China) and the Inst. of Earth Sci. (Taiwan). The major funding for this project was provided by the NSF, Continental Dynamics program. We focus on the receiver function images from the main profile. We observe clear Moho and the upper-mantle discontinuities. The Moho, which in southern Nepal is at 45 km depth (relative to sea level), dips at a gentle angle under the Himalaya. Crossing the Himalaya, its depth rapidly increases, reaching the of 70 km near the Yarlung River. We have succeeded in imagining the Main Himalayan Trust (MHT) as it descends northward at a shallow depth from its surface expression, the Main Frontal Thrust in southern Nepal. In Nepal along the profile, MHT is expressed by a pronounced seismic low velocity zone, which we believe indicates a presence of trapped aqueous fluids in the fault zone, thus lowering the strength of the megathrust. The low velocity associated with the MHT disappears for a short distance north but reappears again as the MHT increases its dip under S. Tibet. We believe the characteristics of the low velocity associated with the MHT in S. Tibet indicate a presence of partial melt due to an increase in depth and frictional heating. A low-velocity wedge above the MHT suggests an accumulation of the melt. This could be an ongoing process of generation of the Himalayan granites. The

  16. Endemic Scrub Typhus–like Illness, Chile

    PubMed Central

    Balcells, M. Elvira; Rabagliati, Ricardo; García, Patricia; Poggi, Helena; Oddó, David; Concha, Marcela; Abarca, Katia; Jiang, Ju; Richards, Allen L.; Fuerst, Paul A.

    2011-01-01

    We report a case of scrub typhus in a 54-year-old man who was bitten by several terrestrial leeches during a trip to Chiloé Island in southern Chile in 2006. A molecular sample, identified as related to Orientia tsutsugamushi based on the sequence of the16S rRNA gene, was obtained from a biopsy specimen of the eschar on the patient’s leg. Serologic analysis showed immunoglobulin G conversion against O. tsutsugamushi whole cell antigen. This case and its associated molecular analyses suggest that an Orientia-like agent is present in the Western Hemisphere that can produce scrub typhus–like illness. The molecular analysis suggests that the infectious agent is closely related, although not identical, to members of the Orientia sp. from Asia. PMID:21888791

  17. Source Mechanisms of Destructive Tsunamigenic Earthquakes occurred along the Major Subduction Zones

    NASA Astrophysics Data System (ADS)

    Yolsal-Çevikbilen, Seda; Taymaz, Tuncay; Ulutaş, Ergin

    2016-04-01

    Subduction zones, where an oceanic plate is subducted down into the mantle by tectonic forces, are potential tsunami locations. Many big, destructive and tsunamigenic earthquakes (Mw > 7.5) and high amplitude tsunami waves are observed along the major subduction zones particularly near Indonesia, Japan, Kuril and Aleutan Islands, Gulf of Alaska, Southern America. Not all earthquakes are tsunamigenic; in order to generate a tsunami, the earthquake must occur under or near the ocean, be large, and create significant vertical movements of the seafloor. It is also known that tsunamigenic earthquakes release their energy over a couple of minutes, have long source time functions and slow-smooth ruptures. In this study, we performed point-source inversions by using teleseismic long-period P- and SH- and broad-band P-waveforms recorded by the Federation of Digital Seismograph Networks (FDSN) and the Global Digital Seismograph Network (GDSN) stations. We obtained source mechanism parameters and finite-fault slip distributions of recent destructive ten earthquakes (Mw ≥ 7.5) by comparing the shapes and amplitudes of long period P- and SH-waveforms, recorded in the distance range of 30° - 90°, with synthetic waveforms. We further obtained finite-fault rupture histories of those earthquakes to determine the faulting area (fault length and width), maximum displacement, rupture duration and stress drop. We applied a new back-projection method that uses teleseismic P-waveforms to integrate the direct P-phase with reflected phases from structural discontinuities near the source, and customized it to estimate the spatio-temporal distribution of the seismic energy release of earthquakes. Inversion results exhibit that recent tsunamigenic earthquakes show dominantly thrust faulting mechanisms with small amount of strike-slip components. Their focal depths are also relatively shallow (h < 40 km). As an example, the September 16, 2015 Illapel (Chile) earthquake (Mw: 8.3; h: 26 km

  18. A Thick, Deformed Sedimentary Wedge in an Erosional Subduction Zone, Southern Costa Rica

    NASA Astrophysics Data System (ADS)

    Silver, E. A.; Kluesner, J. W.; Edwards, J. H.; Vannucchi, P.

    2014-12-01

    A paradigm of erosional subduction zones is that the lower part of the wedge is composed of strong, crystalline basement (Clift and Vannucchi, Rev. Geophys., 42, RG2001, 2004). The CRISP 3D seismic reflection study of the southern part of the Costa Rica subduction zone shows quite the opposite. Here the slope is underlain by a series of fault-cored anticlines, with faults dipping both landward and seaward that root into the plate boundary. Deformation intensity increases with depth, and young, near-surface deformation follows that of the deeper structures but with basin inversions indicating a dynamic evolution (Edwards et al., this meeting). Fold wavelength increases landward, consistent with the folding of a landward-thickening wedge. Offscraping in accretion is minimal because incoming sediments on the lower plate are very thin. Within the wedge, thrust faulting dominates at depth in the wedge, whereas normal faulting dominates close to the surface, possibly reflecting uplift of the deforming anticlines. Normal faults form a mesh of NNW and ENE-trending structures, whereas thrust faults are oriented approximately parallel to the dominant fold orientation, which in turn follows the direction of roughness on the subducting plate. Rapid subduction erosion just prior to 2 Ma is inferred from IODP Expedition 334 (Vannucchi et al., 2013, Geology, 49:995-998). Crystalline basement may have been largely removed from the slope region during this rapid erosional event, and the modern wedge may consist of rapidly redeposited material (Expedition 344 Scientists, 2013) that has been undergoing deformation since its inception, producing a structure quite different from that expected of an eroding subduction zone.

  19. Spatio-temporal biodiversity of soft bottom macrofaunal assemblages in shallow coastal waters exposed to episodic hypoxic events.

    PubMed

    Veas, Rodrigo; Hernández-Miranda, Eduardo; Quiñones, Renato A; Carrasco, Franklin D

    2012-07-01

    The Humboldt Current System (HCS) has one of the three most important oxygen minimum zones (OMZ) of the global ocean. Several studies have looked at the macrofaunal benthic assemblages inhabiting the continental shelf and shallow bays off central-southern Chile associated with low oxygen areas, but little is known about open coast macrofaunal communities within this zone, which are frequently subjected to the low oxygen conditions of Equatorial Subsurface Waters (ESSW). In order to assess local and mesoscale coastal macrofauna dynamics, the sampling area (ca. 40 linear km) was divided into seven local zones (Cobquecura, southern Cobquecura, northern Itata, Itata River mouth, external, southern Itata, and Coliumo). Eight oceanographic cruises were carried out between May 2006 and February 2008 covering 16 coastal sampling sites, between 36°07'S and 36°30'S. The macrofaunal assemblage was dominated by polychaetes, crustaceans, and mollusks. Our results suggest a high degree of temporal faunal stability on the mesoscale in soft bottom communities along the open coast, given the persistence of a faunal assemblage dominated by organisms tolerant of low oxygen conditions. While there is some local variability in community attributes, the main structuring factor for soft bottom communities in the shallow coastal area off central-southern Chile is the seasonal intrusion of low oxygen ESSW. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. An isotopic view of water and nitrate transport through the vadose zone in Oregon's southern Willamette Valley's Groundwater Management Area

    NASA Astrophysics Data System (ADS)

    Brooks, J. R.; Pearlstein, S.; Hutchins, S.; Faulkner, B. R.; Rugh, W.; Willard, K.; Coulombe, R.; Compton, J.

    2017-12-01

    Groundwater nitrate contamination affects thousands of households in Oregon's southern Willamette Valley and many more across the USA. The southern Willamette Valley Groundwater Management Area (GWMA) was established in 2004 due to nitrate levels in the groundwater exceeding the human health standard of 10 mg nitrate-N L-1. Much of the nitrogen (N) inputs to the GWMA comes from agricultural fertilizers, and thus efforts to reduce N inputs to groundwater are focused upon improving N management. However, the effectiveness of these improvements on groundwater quality is unclear because of the complexity of nutrient transport through the vadose zone and long groundwater residence times. Our objective was to focus on vadose zone transport and understand the dynamics and timing of N and water movement below the rooting zone in relation to N management and water inputs. Stable isotopes are a powerful tool for tracking water movement, and understanding N transformations. In partnership with local farmers and state agencies, we established lysimeters and groundwater wells in multiple agricultural fields in the GWMA, and have monitored nitrate, nitrate isotopes, and water isotopes weekly for multiple years. Our results indicate that vadose zone transport is highly complex, and the residence time of water collected in lysimeters was much longer than expected. While input precipitation water isotopes were highly variable over time, lysimeter water isotopes were surprisingly consistent, more closely resembling long-term precipitation isotope means rather than recent precipitation isotopic signatures. However, some particularly large precipitation events with unique isotopic signatures revealed high spatial variability in transport, with some lysimeters showing greater proportions of recent precipitation inputs than others. In one installation where we have groundwater wells and lysimeters at multiple depths, nitrate/nitrite concentrations decreased with depth. N concentrations

  1. ESO Delegation to Visit Chile: the Chile-Eso Treaty and Paranal

    NASA Astrophysics Data System (ADS)

    1994-05-01

    The ESO Council, in its extraordinary session on 28 April 1994, among other matters discussed the relations with the Republic of Chile and the situation around Paranal mountain [1], the designated site for the ESO Very Large Telescope (VLT). Council decided to send a high ranking delegation to Santiago de Chile to discuss with Chilean authorities the pending problems, including the finalisation of the new Treaty between the Republic of Chile and ESO and the legal aspects of the Paranal location. The ESO delegation will consist of Dr. Peter Creola (President of ESO Council), Dr. Catherine Cesarsky (Vice-President of ESO Council), Dr. Henrik Grage (Former Vice-President of ESO Council) and Professor Riccardo Giacconi (ESO Director General), the latter accompanied by his advisers. The delegation will arrive in Chile during the second half of May 1994. The ESO delegation will meet with the Chilean Minister of Foreign Affairs, Mr. Carlos Figueroa, and the Secretary of State in the Ministry of Foreign Affairs, Mr. Jose Miguel Insulza. Other meetings at high level are being planned. The delegation will report about these discussions to the ESO Council during its ordinary session on 7 - 8 June 1994. FOUR PARANAL PHOTOS AVAILABLE A series of four photos which show the current status of the work at Paranal has been prepared. Photographic colour prints for use by the media can be requested from the ESO Information and Photographic Service (please remember to indicate the identification numbers). [1] See ESO Press Release 07/94 of 21 April 1994. PHOTO CAPTIONS ESO PR PHOTO 08/94-1: CERRO PARANAL This aerial photo of the Paranal mountain, the designated site for the ESO Very Large Telescope (VLT), was obtained on 22 March 1994. Paranal is situated in the driest part of the Chilean Atacama desert, approx. 130 km south of the city of Antofagasta, and about 12 km from the Pacific Ocean. In this view towards the West, the ocean is seen in the background. The altitude is 2650 metres

  2. Bona Fide Evidence for Natural Vertical Transmission of Infectious Salmon Anemia Virus in Freshwater Brood Stocks of Farmed Atlantic Salmon (Salmo salar) in Southern Chile

    PubMed Central

    Ramírez, Ramón; Labra, Alvaro; Carmona, Marisela; Muñoz, Cristián

    2014-01-01

    ABSTRACT Infectious salmon anemia (ISA) is a severe disease that affects farmed Atlantic salmon (Salmo salar), causing outbreaks in seawater in most salmon-producing countries worldwide, with particular aggressiveness in southern Chile. The etiological agent of this disease is a virus belonging to the Orthomyxoviridae family, named infectious salmon anemia virus (ISAV). Although it has been suggested that this virus can be vertically transmitted, even in freshwater, there is a lack of compelling experimental evidence to confirm this. Here we demonstrate significant putative viral loads in the ovarian fluid as well as in the eggs of two brood stock female adult specimens that harbored the virus systemically but without clinical signs. The target virus corresponded to a highly polymorphic region 3 (HPR-3) variant, which is known to be virulent in seawater and responsible for recent and past outbreaks of this disease in Chile. Additionally, the virus recovered from the fluid as well as from the interior of the eggs was fully infective to a susceptible fish cell line. To our knowledge, this is the first robust evidence demonstrating mother-to-offspring vertical transmission of the infective virus on the one hand and the asymptomatic transmission of a virulent form of the virus in freshwater fish on the other hand. IMPORTANCE The robustness of the data presented here will contribute to a better understanding of the biology of the virus but most importantly will constitute a key management tool in the control of an aggressive agent constantly threatening the sustainability of the global salmon industry. PMID:24623436

  3. Bona fide evidence for natural vertical transmission of infectious salmon anemia virus in freshwater brood stocks of farmed Atlantic salmon (Salmo salar) in Southern Chile.

    PubMed

    Marshall, Sergio H; Ramírez, Ramón; Labra, Alvaro; Carmona, Marisela; Muñoz, Cristián

    2014-06-01

    Infectious salmon anemia (ISA) is a severe disease that affects farmed Atlantic salmon (Salmo salar), causing outbreaks in seawater in most salmon-producing countries worldwide, with particular aggressiveness in southern Chile. The etiological agent of this disease is a virus belonging to the Orthomyxoviridae family, named infectious salmon anemia virus (ISAV). Although it has been suggested that this virus can be vertically transmitted, even in freshwater, there is a lack of compelling experimental evidence to confirm this. Here we demonstrate significant putative viral loads in the ovarian fluid as well as in the eggs of two brood stock female adult specimens that harbored the virus systemically but without clinical signs. The target virus corresponded to a highly polymorphic region 3 (HPR-3) variant, which is known to be virulent in seawater and responsible for recent and past outbreaks of this disease in Chile. Additionally, the virus recovered from the fluid as well as from the interior of the eggs was fully infective to a susceptible fish cell line. To our knowledge, this is the first robust evidence demonstrating mother-to-offspring vertical transmission of the infective virus on the one hand and the asymptomatic transmission of a virulent form of the virus in freshwater fish on the other hand. The robustness of the data presented here will contribute to a better understanding of the biology of the virus but most importantly will constitute a key management tool in the control of an aggressive agent constantly threatening the sustainability of the global salmon industry.

  4. Green Chile Pepper Harvest Mechanization

    USDA-ARS?s Scientific Manuscript database

    Pungent green chile (genus /Capsicum/, also spelled chili) is a large, fragile fruit growing on berry shrubs. Chile is harvested by hand to maximize yields and minimize fruit damage. Labor for hand harvesting chile is increasingly costly and difficult to obtain. Harvest mechanization is viewed as...

  5. Wave-induced bedload transport - a study of the southern Baltic coastal zone

    NASA Astrophysics Data System (ADS)

    Dudkowska, Aleksandra; Gic-Grusza, Gabriela

    2017-03-01

    The wave-induced bedload transport and spatial distribution of its magnitude in the southern Baltic coastal zone of Poland are estimated. The vicinity of Lubiatowo was selected as a representative part of the Polish coast. It was assumed that transport is a function of shear stress; alternative approaches, based on force balances and discharge relationships, were not considered in the present study. Four models were studied and compared over a wide range of bottom shear stress and wind-wave conditions. The set of models comprises classic theories that assume a simplified influence of turbulence on sediment transport (e.g., advocated by authors such as Du Boys, Meyer-Peter and Müller, Ribberink, Engelund and Hansen). It is shown that these models allow to estimate transport comparable to measured values under similar environmental conditions. A united general model for bedload transport is proposed, and a set of maps of wave bedload transport for various wind conditions in the study area is presented.

  6. Protecting Dark Skies in Chile

    NASA Astrophysics Data System (ADS)

    Smith, R. Chris; Sanhueza, Pedro; Phillips, Mark

    2018-01-01

    Current projections indicate that Chile will host approximately 70% of the astronomical collecting area on Earth by 2030, augmenting the enormous area of ALMA with that of three next-generation optical telescopes: LSST, GMTO, and E-ELT. These cutting-edge facilities represent billions of dollars of investment in the astronomical facilities hosted in Chile. The Chilean government, Chilean astronomical community, and the international observatories in Chile have recognized that these investments are threatened by light pollution, and have formed a strong collaboration to work at managing the threats. We will provide an update on the work being done in Chile, ranging from training municipalities about new lighting regulations to exploring international recognition of the dark sky sites of Northern Chile.

  7. A 600-year-long stratigraphic record of tsunamis in south-central Chile

    USGS Publications Warehouse

    Hong, Isabel; Dura, Tina; Ely, Lisa L.; Horton, Benajamin P.; Nelson, Alan R.; Cisternas, Marco; Nikitina, Daria; Wesson, Robert L.

    2017-01-01

    The stratigraphy within coastal river valleys in south-central Chile clarifies and extends the region’s history of large, earthquakes and accompanying tsunamis. Our site at Quidico (38.1°S, 73.3°W) is located in an overlap zone between ruptures of magnitude 8–9 earthquakes in 1960 and 2010, and, therefore, records tsunamis originating from subduction-zone ruptures north and south of the city of Concepción. Hand-dug pits and cores in a 3-m-thick sequence of freshwater peat in an abandoned meander (a little-examined depositional environment for tsunami deposits) and exposures along the Quidico River show five sand beds that extend as much as 1.2 km inland. Evidence for deposition of the beds by tsunamis includes tabular sand beds that are laterally extensive (>100 m), well sorted, fine upward, have sharp lower contacts, and contain diatom assemblages dominated by brackish and marine taxa. Using eyewitness accounts of tsunami inundation, 137Cs analyses, and 14C dating, we matched the upper four sand beds with historical tsunamis in 2010, 1960, 1835, and 1751. The oldest prehistoric bed dates to 1445–1490 CE and correlates with lacustrine and coastal records of similar-aged earthquakes and tsunamis in south-central Chile.

  8. Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in Chile.

    PubMed

    Garavelli, Lysel; Colas, François; Verley, Philippe; Kaplan, David Michael; Yannicelli, Beatriz; Lett, Christophe

    2016-01-01

    In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in Chile. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to southern Chile. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future.

  9. Induced abortion and associated factors in health facilities of Guraghe zone, southern Ethiopia.

    PubMed

    Tesfaye, Gezahegn; Hambisa, Mitiku Teshome; Semahegn, Agumasie

    2014-01-01

    Unsafe abortion is one of the major medical and public health problems in developing countries including Ethiopia. However, there is a lack of up-to-date and reliable information on induced abortion distribution and its determinant factors in the country. This study was intended to assess induced abortion and associated factors in health facilities of Guraghe zone, Southern Ethiopia. Institution based cross-sectional study was conducted in eight health facilities in Guraghe zone. Client exit interview was conducted on 400 patients using a structured questionnaire. Bivariate and multivariate logistic regression analysis was performed to identify factors associated with induced abortion. Out of 400 women, 75.5% responded that the current pregnancy that ended in abortion is unwanted. However, only 12.3% of the respondents have admitted interference to the current pregnancy. Having more than four pregnancies (AOR = 4.28, CI: (1.24-14.71)), age of 30-34 years (AOR = 0.15, CI: (0.04-0.55)), primary education (AOR = 0.26, CI: (0.13-0.88)), and wanted pregnancy (AOR = 0.44, CI: (0.14-0.65)) were found to have association with induced abortion. The study revealed high level of induced abortion which is underpinned by high magnitude of unwanted pregnancy. There is requirement for widespread expansion of increased access to high quality family planning service and post-abortion care.

  10. Characterization of the epidemiology of bat-borne rabies in Chile between 2003 and 2013.

    PubMed

    Alegria-Moran, Raul; Miranda, Daniela; Barnard, Matt; Parra, Alonso; Lapierre, Lisette

    2017-08-01

    Rabies is a zoonotic disease of great impact to public health. According to the World Health Organization, the country of Chile is currently declared free from human rabies transmitted by dogs. An epidemiological characterization and description was conducted using rabies data from 2003 to 2013 held by the National Program for Prevention and Control of Rabies from the Ministry of Health, consisting of bats samples reported as suspect and samples taken by active surveillance (bats brain tissue). Spatial autocorrelation analysis was performed using Local Indicators of Spatial Association (LISA) statistics, particularly Moran's I index, for the detection of spatial clusters. Temporal descriptive analysis was also carried out. Nine hundred and twenty-seven positive cases were reported, presenting an average of 84 cases per year, mainly originated from passive surveillance (98.5%), whilst only 1.5% of cases were reported by active surveillance. Global positivity for the study period was 7.02% and 0.1% in passive and active surveillance respectively. Most of the cases were reported in the central zone of Chile (88.1%), followed by south zone (9.1%) and north zone (2.8%). At a regional level, Metropolitana (40.6%), Valparaíso (19.1%) and Maule (11.8%) regions reported the majority of the cases. Tadarida brasiliensis (92%) presented the majority of the cases reported, with viral variant 4 (82%) being most commonly diagnosed. Only two cases were detected in companion animals. The central zone presented a positive spatial autocorrelation (Moran's I index=0.1537, 95% CI=0.1141-0.1933; p-value=0.02); north and south zones returned non-significant results (Moran's I index=0.0517 and -0.0117, 95% CI=-0.0358-0.1392 and -0.0780-0.0546, and p-values=0.21 and 0.34 respectively). The number of rabies cases decreased between May and August (late fall and winter) and tended to increase during the hot season (December to March), confirmed with the evidence from Autocorrelation analysis

  11. Fault-zone waves observed at the southern Joshua Tree earthquake rupture zone

    USGS Publications Warehouse

    Hough, S.E.; Ben-Zion, Y.; Leary, P.

    1994-01-01

    Waveform and spectral characteristics of several aftershocks of the M 6.1 22 April 1992 Joshua Tree earthquake recorded at stations just north of the Indio Hills in the Coachella Valley can be interpreted in terms of waves propagating within narrow, low-velocity, high-attenuation, vertical zones. Evidence for our interpretation consists of: (1) emergent P arrivals prior to and opposite in polarity to the impulsive direct phase; these arrivals can be modeled as headwaves indicative of a transfault velocity contrast; (2) spectral peaks in the S wave train that can be interpreted as internally reflected, low-velocity fault-zone wave energy; and (3) spatial selectivity of event-station pairs at which these data are observed, suggesting a long, narrow geologic structure. The observed waveforms are modeled using the analytical solution of Ben-Zion and Aki (1990) for a plane-parallel layered fault-zone structure. Synthetic waveform fits to the observed data indicate the presence of NS-trending vertical fault-zone layers characterized by a thickness of 50 to 100 m, a velocity decrease of 10 to 15% relative to the surrounding rock, and a P-wave quality factor in the range 25 to 50.

  12. Causes, Dynamics and Impacts of Lahar Mass Flows due to the April 2015 Eruption of Calbuco Volcano, Chile

    NASA Astrophysics Data System (ADS)

    Dussaillant, Alejandro; Russell, Andy; Meier, Claudio; Rivera, Andres; Mella, Mauricio; Garrido, Natalia; Hernandez, Jorge; Napoleoni, Felipe; Gonzalez, Cristian

    2016-04-01

    Calbuco is a 2015m high, glacier capped, stratovolcano in the heavily populated Los Lagos region of southern Chile with a history of large volcanic eruptions in 1893-95, 1906-7, 1911-12, 1917, 1932, 1945, 1961 and 1972. Calbuco volcano experienced a powerful 90 minute eruption at 18:04h on 22 April, 2015 followed by additional major eruptions at 01:00h and 13:10h on 23 & 30 April, respectively, resulting in the evacuation of 6500 people and the imposition of a 20 km radius exclusion zone. Pyroclastic flows descended into several river catchments radiating from the volcano with lahars travelling distances of up to 14 km, reaching populated areas. We present findings from detailed field observations from April and July 2015, and January 2016, regarding the causes, dynamics and impacts of lahars generated by the April 2015 eruption, supported by satellite imagery, LiDAR and detailed rtkGPS & TLS surveys, as well as sediment sampling. Pyroclastic flows melted glacier ice and snow generating the largest lahars in the Rio Este and Rio Blanco Sur on the southern flanks of the volcano. Lahar deposits in the Rio Blanco Norte were buried by pyroclastic flow deposits with measured temperatures of up to 282°C three months after emplacement. Lahar erosional impacts included bedrock erosion, alluvial channel incision, erosion of surficial deposits and the felling of large areas of forest. Depositional landforms included boulder run-ups on the outsides of channel bends, boulder clusters and large woody debris jams. Lahars deposited up to 8m of sediment within distal reaches. Deposits on the southern flanks of Calbuco indicate the passage of multiple pulses of contrasting rheology. Lahar occurrence and magnitude was controlled by the pre-eruption distribution of snow and ice on the volcano. Pre-existing lahar channels controlled flows to lower piedmont zones where routing was determined by palaeo-lahar geomorphology. Ongoing erosion of proximal pyroclastic flow and lahar deposits

  13. Air-sea interaction regimes in the sub-Antarctic Southern Ocean and Antarctic marginal ice zone revealed by icebreaker measurements

    NASA Astrophysics Data System (ADS)

    Yu, Lisan; Jin, Xiangze; Schulz, Eric W.; Josey, Simon A.

    2017-08-01

    This study analyzed shipboard air-sea measurements acquired by the icebreaker Aurora Australis during its off-winter operation in December 2010 to May 2012. Mean conditions over 7 months (October-April) were compiled from a total of 22 ship tracks. The icebreaker traversed the water between Hobart, Tasmania, and the Antarctic continent, providing valuable in situ insight into two dynamically important, yet poorly sampled, regimes: the sub-Antarctic Southern Ocean and the Antarctic marginal ice zone (MIZ) in the Indian Ocean sector. The transition from the open water to the ice-covered surface creates sharp changes in albedo, surface roughness, and air temperature, leading to consequential effects on air-sea variables and fluxes. Major effort was made to estimate the air-sea fluxes in the MIZ using the bulk flux algorithms that are tuned specifically for the sea-ice effects, while computing the fluxes over the sub-Antarctic section using the COARE3.0 algorithm. The study evidenced strong sea-ice modulations on winds, with the southerly airflow showing deceleration (convergence) in the MIZ and acceleration (divergence) when moving away from the MIZ. Marked seasonal variations in heat exchanges between the atmosphere and the ice margin were noted. The monotonic increase in turbulent latent and sensible heat fluxes after summer turned the MIZ quickly into a heat loss regime, while at the same time the sub-Antarctic surface water continued to receive heat from the atmosphere. The drastic increase in turbulent heat loss in the MIZ contrasted sharply to the nonsignificant and seasonally invariant turbulent heat loss over the sub-Antarctic open water.Plain Language SummaryThe icebreaker Aurora Australis is a research and supply vessel that is regularly chartered by the Australian Antarctic Division during the <span class="hlt">southern</span> summer to operate in waters between Hobart, Tasmania, and Antarctica. The vessel serves as the main lifeline to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70157275','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70157275"><span>Dynamics of a large, restless, rhyolitic magma system at Laguna del Maule, <span class="hlt">southern</span> Andes, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Singer, Brad S.; Andersen, Nathan L.; Le Mével, Hélène; Feigl, Kurt L.; DeMets, Charles; Tikoff, Basil; Thurber, Clifford H.; Jicha, Brian R.; Cardonna, Carlos; Córdova, Loreto; Gil, Fernando; Unsworth, Martyn J.; Williams-Jones, Glyn; Miller, Craig W.; Fierstein, Judith; Hildreth, Edward; Vazquez, Jorge A.</p> <p>2014-01-01</p> <p>Explosive eruptions of large-volume rhyolitic magma systems are common in the geologic record and pose a major potential threat to society. Unlike other natural hazards, such as earthquakes and tsunamis, a large rhyolitic volcano may provide warning signs long before a caldera-forming eruption occurs. Yet, these signs—and what they imply about magma-crust dynamics—are not well known. This is because we have learned how these systems form, grow, and erupt mainly from the study of ash flow tuffs deposited tens to hundreds of thousands of years ago or more, or from the geophysical imaging of the unerupted portions of the reservoirs beneath the associated calderas. The Laguna del Maule Volcanic Field, <span class="hlt">Chile</span>, includes an unusually large and recent concentration of silicic eruptions. Since 2007, the crust there has been inflating at an astonishing rate of at least 25 cm/yr. This unique opportunity to investigate the dynamics of a large rhyolitic system while magma migration, reservoir growth, and crustal deformation are actively under way is stimulating a new international collaboration. Findings thus far lead to the hypothesis that the silicic vents have tapped an extensive layer of crystal-poor, rhyolitic melt that began to form atop a magmatic mush <span class="hlt">zone</span> that was established by ca. 20 ka with a renewed phase of rhyolite eruptions during the Holocene. Modeling of surface deformation, magnetotelluric data, and gravity changes suggest that magma is currently intruding at a depth of ~5 km. The next phase of this investigation seeks to enlarge the sets of geophysical and geochemical data and to use these observations in numerical models of system dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1412555L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1412555L"><span>Subduction in the <span class="hlt">Southern</span> Caribbean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Levander, A.; Schmitz, M.; Bezada, M.; Masy, J.; Niu, F.; Pindell, J.</p> <p>2012-04-01</p> <p>The <span class="hlt">southern</span> Caribbean is bounded at either end by subduction <span class="hlt">zones</span>: In the east at the Lesser Antilles subduction <span class="hlt">zone</span> the Atlantic part of the South American plate subducts beneath the Caribbean. In the north and west under the <span class="hlt">Southern</span> Caribbean Deformed Belt accretionary prism, the Caribbean subducts under South America. In a manner of speaking, the two plates subduct beneath each other. Finite-frequency teleseismic P-wave tomography confirms this, imaging the Atlantic and the Caribbean subducting steeply in opposite directions to transition <span class="hlt">zone</span> depths under northern South America (Bezada et al, 2010). The two subduction <span class="hlt">zones</span> are connected by the El Pilar-San Sebastian strike-slip fault system, a San Andreas scale system. A variety of seismic probes identify where the two plates tear as they begin to subduct (Niu et al, 2007; Clark et al., 2008; Miller et al. 2009; Masy et al, 2009). The El Pilar system forms at the southeastern corner of the Antilles subduction <span class="hlt">zone</span> by the Atlantic tearing from South America. The deforming plate edges control mountain building and basin formation at the eastern end of the strike-slip system. In northwestern South America the Caribbean plate tears, its southernmost element subducting at shallow angles under northernmost Colombia and then rapidly descending to transition <span class="hlt">zone</span> depths under Lake Maracaibo (Bezada et al., 2010). We believe that the flat slab produces the Merida Andes, the Perija, and the Santa Marta ranges. The <span class="hlt">southern</span> edge of the nonsubducting Caribbean plate underthrusts northern Venezuela to about the width of the coastal mountains (Miller et al., 2009). We infer that the underthrust Caribbean plate supports the coastal mountains, and controls continuing deformation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26PSL.473..190B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26PSL.473..190B"><span>Immediate propagation of deglacial environmental change to deep-marine turbidite systems along the <span class="hlt">Chile</span> convergent margin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bernhardt, Anne; Schwanghart, Wolfgang; Hebbeln, Dierk; Stuut, Jan-Berend W.; Strecker, Manfred R.</p> <p>2017-09-01</p> <p>Understanding how Earth-surface processes respond to past climatic perturbations is crucial for making informed predictions about future impacts of climate change on sediment fluxes. Sedimentary records provide the archives for inferring these processes, but their interpretation is compromised by our incomplete understanding of how sediment-routing systems respond to millennial-scale climate cycles. We analyzed seven sediment cores recovered from marine turbidite depositional sites along the <span class="hlt">Chile</span> continental margin. The sites span a pronounced arid-to-humid gradient with variable relief and related sediment connectivity of terrestrial and marine environments. These sites allowed us to study event-related depositional processes in different climatic and geomorphic settings from the Last Glacial Maximum to the present day. The three sites reveal a steep decline of turbidite deposition during deglaciation. High rates of sea-level rise postdate the decline in turbidite deposition. Comparison with paleoclimate proxies documents that the spatio-temporal sedimentary pattern rather mirrors the deglacial humidity decrease and concomitant warming with no resolvable lag times. Our results let us infer that declining deglacial humidity decreased fluvial sediment supply. This signal propagated rapidly through the highly connected systems into the marine sink in north-central <span class="hlt">Chile</span>. In contrast, in south-central <span class="hlt">Chile</span>, connectivity between the Andean erosional <span class="hlt">zone</span> and the fluvial transfer <span class="hlt">zone</span> probably decreased abruptly by sediment trapping in piedmont lakes related to deglaciation, resulting in a sudden decrease of sediment supply to the ocean. Additionally, reduced moisture supply may have contributed to the rapid decline of turbidite deposition. These different causes result in similar depositional patterns in the marine sinks. We conclude that turbiditic strata may constitute reliable recorders of climate change across a wide range of climatic <span class="hlt">zones</span> and geomorphic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..44.2427F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..44.2427F"><span>Tsunamigenic potential of a newly discovered active fault <span class="hlt">zone</span> in the outer Messina Strait, <span class="hlt">Southern</span> Italy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fu, Lili; Heidarzadeh, Mohammad; Cukur, Deniz; Chiocci, Francesco L.; Ridente, Domenico; Gross, Felix; Bialas, Jörg; Krastel, Sebastian</p> <p>2017-03-01</p> <p>The 1908 Messina tsunami was the most catastrophic tsunami hitting the coastline of <span class="hlt">Southern</span> Italy in the younger past. The source of this tsunami, however, is still heavily debated, and both rupture along a fault and a slope failure have been postulated as potential origin of the tsunami. Here we report a newly discovered active Fiumefreddo-Melito di Porto Salvo Fault <span class="hlt">Zone</span> (F-MPS_FZ), which is located in the outer Messina Strait in a proposed landslide source area of the 1908 Messina tsunami. Tsunami modeling showed that this fault <span class="hlt">zone</span> would produce devastating tsunamis by assuming slip amounts of ≥5 m. An assumed slip of up to 17 m could even generate a tsunami comparable to the 1908 Messina tsunami, but we do not consider the F-MPS_FZ as a source for the 1908 Messina tsunami because its E-W strike contradicts seismological observations of the 1908 Messina earthquake. Future researches on the F-MPS_FZ, however, may contribute to the tsunami risk assessment in the Messina Strait.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5404655','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5404655"><span>Knowledge, attitudes, and practices regarding hantavirus disease and acceptance of a vaccine trial in rural communities of <span class="hlt">southern</span> <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Valdivieso, Francisca; Gonzalez, Claudia; Najera, Manuel; Olea, Andrea; Cuiza, Analia; Aguilera, Ximena; Mertz, Gregory</p> <p>2017-01-01</p> <p>ABSTRACT Andes hantavirus cardiopulmonary syndrome, transmitted by Oligoryzomys longicaudatus, has no approved treatment, a case fatality rate of 35%, and documented person-to-person transmission. An Andes vaccine, highly needed for prevention, is in development. We aimed to evaluate knowledge, attitudes and practices (KAP) regarding hantavirus disease and willingness to participate in a future Andes vaccine trials through a cross sectional face-to-face oral survey of a randomly selected adult sample from 2 rural communes in <span class="hlt">southern</span> <span class="hlt">Chile</span>. Human subjects approval was obtained from our institutional IRBs, and participants signed informed consent. We enrolled 319 subjects from Corral and 321 from Curarrehue; 98% had heard about hantavirus disease and its reservoir but only half knew about transmission, symptoms and prevention. Participants fear the disease but are only partially aware of their own risk. One third of participants reported presence of rodents inside their homes. Despite moderate confidence in their health system, most subjects perceived vaccines as beneficial, and 93% would accept an approved hantavirus vaccine. Half would agree to participate in a vaccine trial and 29% would allow their children to participate. Motivations to participate were mainly altruistic, while risk perception was the main reason for declining. Knowledge about hantavirus disease and prevention practices require reinforcement, and a vaccine trial seems feasible in these populations. PMID:27830976</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3571418','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3571418"><span>A hybrid <span class="hlt">zone</span> of the genus Ctenomys: A case study in <span class="hlt">southern</span> Brazil</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Castilho, Camila S.; Gava, Adriana; de Freitas, Thales R.O.</p> <p>2012-01-01</p> <p>We describe variation at microsatellite loci and the chromosomal polymorphisms of a hybrid population, and hybridizing populations of Ctenomys minutus (the minor tuco-tuco) from the coastal plain of Rio Grande do Sul, <span class="hlt">southern</span> Brazil. Cytogenetic analysis and a survey of six microsatellite loci included 101 specimens of C. minutus from the parental populations (2n/AN = 42/74 and 48a/76) and their contact <span class="hlt">zone</span>. Cytogenetic analysis recorded 26 different karyotypes exhibited by 50 individuals from the hybrid population. Of the 26 karyotypes, only 14% presented a parental-like configuration, and none had the combinations of 2n and AN expected for an F1 hybrid. The remaining karyotypes were alternative hybrid forms, with 2n varying from 42 to 46 and AN from 68 to 80. These results suggest chromosomal rearrangements are only of minor significance in the establishment of reproductive barriers for this species. PMID:23412911</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3518181','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3518181"><span>The influence of climatic conditions on the transmission dynamics of the 2009 A/H1N1 influenza pandemic in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2012-01-01</p> <p>Background The role of demographic factors, climatic conditions, school cycles, and connectivity patterns in shaping the spatio-temporal dynamics of pandemic influenza is not clearly understood. Here we analyzed the spatial, age and temporal evolution of the 2009 A/H1N1 influenza pandemic in <span class="hlt">Chile</span>, a <span class="hlt">southern</span> hemisphere country covering a long and narrow strip comprising latitudes 17°S to 56°S. Methods We analyzed the dissemination patterns of the 2009 A/H1N1 pandemic across 15 regions of <span class="hlt">Chile</span> based on daily hospitalizations for severe acute respiratory disease and laboratory confirmed A/H1N1 influenza infection from 01-May to 31-December, 2009. We explored the association between timing of pandemic onset and peak pandemic activity and several geographical and demographic indicators, school vacations, climatic factors, and international passengers. We also estimated the reproduction number (R) based on the growth rate of the exponential pandemic phase by date of symptoms onset, estimated using maximum likelihood methods. Results While earlier pandemic onset was associated with larger population size, there was no association with connectivity, demographic, school or climatic factors. In contrast, there was a latitudinal gradient in peak pandemic timing, representing a 16-39-day lag in disease activity from the <span class="hlt">southern</span> regions relative to the northernmost region (P < 0.001). Geographical differences in latitude of Chilean regions, maximum temperature and specific humidity explained 68.5% of the variability in peak timing (P = 0.01). In addition, there was a decreasing gradient in reproduction number from south to north <span class="hlt">Chile</span> (P < 0.0001). The regional mean R estimates were 1.6-2.0, 1.3-1.5, and 1.2-1.3 for <span class="hlt">southern</span>, central and northern regions, respectively, which were not affected by the winter vacation period. Conclusions There was a lag in the period of most intense 2009 pandemic influenza activity following a South to North traveling pattern across regions</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.T31B0629G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.T31B0629G"><span>Discovering the Complexity of Capable Faults in Northern <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gonzalez, G.; del Río, I. A.; Rojas Orrego, C., Sr.; Astudillo, L. A., Sr.</p> <p>2017-12-01</p> <p>Great crustal earthquakes (Mw >7.0) in the upper plate of subduction <span class="hlt">zones</span> are relatively uncommon and less well documented. We hypothesize that crustal earthquakes are poorly represented in the instrumental record because they have long recurrence intervals. In northern <span class="hlt">Chile</span>, the extreme long-term aridity permits extraordinary preservation of landforms related to fault activity, making this region a primary target to understand how upper plate faults work at subduction <span class="hlt">zones</span>. To understand how these faults relate to crustal seismicity in the long-term, we have conducted a detailed palaeoseismological study. We performed a palaeoseismological survey integrating trench logging and photogrammetry based on UAVs. Optically stimulated luminescence (OSL) age determinations were practiced for dating deposits linked to faulting. In this contribution we present the study case of two primary faults located in the Coastal Cordillera of northern <span class="hlt">Chile</span> between Iquique (21ºS) and Antofagasta (24ºS). We estimate the maximum moment magnitude of earthquakes generated in these upper plate faults, their recurrence interval and the fault-slip rate. We conclude that the studied upper plate faults show a complex kinematics on geological timescales. Faults seem to change their kinematics from normal (extension) to reverse (compression) or from normal to transcurrent (compression) according to the stage of subduction earthquake cycle. Normal displacement is related to coseismic stages and compression is linked to interseismic period. As result this complex interaction these faults are capable of generating Mw 7.0 earthquakes, with recurrence times on the order of thousands of years during every stage of the subduction earthquake cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70101156','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70101156"><span>Miocene burial and exhumation of the India-Asia collision <span class="hlt">zone</span> in <span class="hlt">southern</span> Tibet: response to slab dynamics and erosion</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Carrapa, Barbara; Orme, D.A.; DeCelles, Peter G.; Kapp, Paul; Cosca, Michael A.; Waldrip, R.</p> <p>2014-01-01</p> <p>The India-Asia collision <span class="hlt">zone</span> in <span class="hlt">southern</span> Tibet preserves a record of geodynamic and erosional processes following intercontinental collision. Apatite fission-track and zircon and apatite (U-Th)/He data from the Oligocene–Miocene Kailas Formation, within the India-Asia collision <span class="hlt">zone</span>, show a synchronous cooling signal at 17 ± 1 Ma, which is younger than the ca. 26–21 Ma depositional age of the Kailas Formation, constrained by U-Pb and 40Ar/39Ar geochronology, and requires heating (burial) after ca. 21 Ma and subsequent rapid exhumation. Data from the Gangdese batholith underlying the Kailas Formation also indicate Miocene exhumation. The thermal history of the Kailas Formation is consistent with rapid subsidence during a short-lived phase of early Miocene extension followed by uplift and exhumation driven by rollback and northward underthrusting of the Indian plate, respectively. Significant removal of material from the India-Asia collision <span class="hlt">zone</span> was likely facilitated by efficient incision of the paleo–Indus River and paleo–Yarlung River in response to drainage reorganization and/or intensification of the Asian monsoon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JSAES..55...83W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JSAES..55...83W"><span>Quaternary incised valleys in <span class="hlt">southern</span> Brazil coastal <span class="hlt">zone</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weschenfelder, Jair; Baitelli, Ricardo; Corrêa, Iran C. S.; Bortolin, Eduardo C.; dos Santos, Cristiane B.</p> <p>2014-11-01</p> <p>High-resolution seismic records obtained in the Rio Grande do Sul coastal <span class="hlt">zone</span>, <span class="hlt">southern</span> Brazil, revealed that prominent valleys and channels developed in the area before the installation of actual coastal plain. Landwards, the paleoincisions can be linked with the present courses of the main river dissecting the area. Oceanwards, they can be linked with related features previously recognized in the continental shelf and slope by means of seismic and morphostructural studies. Based mainly on seismic, core data and geologic reasoning, it can be inferred that the coastal valleys were incised during forced regression events into the coastal prism deposited during previous sea level highstand events of the Quaternary. Seismic data has revealed paleovalleys up to 10 km wide and, in some places, infilled with up to 40 m thick of sediments. The results indicated two distinct periods of cut-and-fill events in the Patos Lagoon area. The filling of the younger incision system is mainly Holocene and its onset is related to the last main regressive event of the Pleistocene, when the sea level fell about 130 m below the actual position. The older incision and filling event is related to the previous regressive-transgressive events of the Middle and Late Pleistocene. The fluvial discharge fed delta systems on the shelf edge during the sea level lowstands. The subsequent transgressions drowned the incised drainage, infilling it and closing the inlets formerly connecting the coastal river to the ocean. The incised features may have played a significant role on the basin-margin architecture, facies distribution and accommodation space during the multitude of up and down sea level events of the Quaternary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27109362','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27109362"><span>Accelerated nucleation of the 2014 Iquique, <span class="hlt">Chile</span> Mw 8.2 Earthquake.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kato, Aitaro; Fukuda, Jun'ichi; Kumazawa, Takao; Nakagawa, Shigeki</p> <p>2016-04-25</p> <p>The earthquake nucleation process has been vigorously investigated based on geophysical observations, laboratory experiments, and theoretical studies; however, a general consensus has yet to be achieved. Here, we studied nucleation process for the 2014 Iquique, <span class="hlt">Chile</span> Mw 8.2 megathrust earthquake located within the current North <span class="hlt">Chile</span> seismic gap, by analyzing a long-term earthquake catalog constructed from a cross-correlation detector using continuous seismic data. Accelerations in seismicity, the amount of aseismic slip inferred from repeating earthquakes, and the background seismicity, accompanied by an increasing frequency of earthquake migrations, started around 270 days before the mainshock at locations up-dip of the largest coseismic slip patch. These signals indicate that repetitive sequences of fast and slow slip took place on the plate interface at a transition <span class="hlt">zone</span> between fully locked and creeping portions. We interpret that these different sliding modes interacted with each other and promoted accelerated unlocking of the plate interface during the nucleation phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...624792K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...624792K"><span>Accelerated nucleation of the 2014 Iquique, <span class="hlt">Chile</span> Mw 8.2 Earthquake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kato, Aitaro; Fukuda, Jun'Ichi; Kumazawa, Takao; Nakagawa, Shigeki</p> <p>2016-04-01</p> <p>The earthquake nucleation process has been vigorously investigated based on geophysical observations, laboratory experiments, and theoretical studies; however, a general consensus has yet to be achieved. Here, we studied nucleation process for the 2014 Iquique, <span class="hlt">Chile</span> Mw 8.2 megathrust earthquake located within the current North <span class="hlt">Chile</span> seismic gap, by analyzing a long-term earthquake catalog constructed from a cross-correlation detector using continuous seismic data. Accelerations in seismicity, the amount of aseismic slip inferred from repeating earthquakes, and the background seismicity, accompanied by an increasing frequency of earthquake migrations, started around 270 days before the mainshock at locations up-dip of the largest coseismic slip patch. These signals indicate that repetitive sequences of fast and slow slip took place on the plate interface at a transition <span class="hlt">zone</span> between fully locked and creeping portions. We interpret that these different sliding modes interacted with each other and promoted accelerated unlocking of the plate interface during the nucleation phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4842989','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4842989"><span>Accelerated nucleation of the 2014 Iquique, <span class="hlt">Chile</span> Mw 8.2 Earthquake</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kato, Aitaro; Fukuda, Jun’ichi; Kumazawa, Takao; Nakagawa, Shigeki</p> <p>2016-01-01</p> <p>The earthquake nucleation process has been vigorously investigated based on geophysical observations, laboratory experiments, and theoretical studies; however, a general consensus has yet to be achieved. Here, we studied nucleation process for the 2014 Iquique, <span class="hlt">Chile</span> Mw 8.2 megathrust earthquake located within the current North <span class="hlt">Chile</span> seismic gap, by analyzing a long-term earthquake catalog constructed from a cross-correlation detector using continuous seismic data. Accelerations in seismicity, the amount of aseismic slip inferred from repeating earthquakes, and the background seismicity, accompanied by an increasing frequency of earthquake migrations, started around 270 days before the mainshock at locations up-dip of the largest coseismic slip patch. These signals indicate that repetitive sequences of fast and slow slip took place on the plate interface at a transition <span class="hlt">zone</span> between fully locked and creeping portions. We interpret that these different sliding modes interacted with each other and promoted accelerated unlocking of the plate interface during the nucleation phase. PMID:27109362</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1215701B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1215701B"><span>2010 <span class="hlt">Chile</span> Earthquake Aftershock Response</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barientos, Sergio</p> <p>2010-05-01</p> <p>The Mw=8.8 earthquake off the coast of <span class="hlt">Chile</span> on 27 February 2010 is the 5th largest megathrust earthquake ever to be recorded and provides an unprecedented opportunity to advance our understanding of megathrust earthquakes and associated phenomena. The 2010 <span class="hlt">Chile</span> earthquake ruptured the Concepcion-Constitucion segment of the Nazca/South America plate boundary, south of the Central <span class="hlt">Chile</span> region and triggered a tsunami along the coast. Following the 2010 earthquake, a very energetic aftershock sequence is being observed in an area that is 600 km along strike from Valparaiso to 150 km south of Concepcion. Within the first three weeks there were over 260 aftershocks with magnitude 5.0 or greater and 18 with magnitude 6.0 or greater (NEIC, USGS). The Concepcion-Constitucion segment lies immediately north of the rupture <span class="hlt">zone</span> associated with the great magnitude 9.5 <span class="hlt">Chile</span> earthquake, and south of the 1906 and the 1985 Valparaiso earthquakes. The last great subduction earthquake in the region dates back to the February 1835 event described by Darwin (1871). Since 1835, part of the region was affected in the north by the Talca earthquake in December 1928, interpreted as a shallow dipping thrust event, and by the Chillan earthquake (Mw 7.9, January 1939), a slab-pull intermediate depth earthquake. For the last 30 years, geodetic studies in this area were consistent with a fully coupled elastic loading of the subduction interface at depth; this led to identify the area as a mature seismic gap with potential for an earthquake of magnitude of the order 8.5 or several earthquakes of lesser magnitude. What was less expected was the partial rupturing of the 1985 segment toward north. Today, the 2010 earthquake raises some disturbing questions: Why and how the rupture terminated where it did at the northern end? How did the 2010 earthquake load the adjacent segment to the north and did the 1985 earthquake only partially ruptured the plate interface leaving loaded asperities since</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.G44A..02B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.G44A..02B"><span>The GNSS Component of the Seismic Monitoring System in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barrientos, S. E.</p> <p>2016-12-01</p> <p><span class="hlt">Chile</span> is amongst the most seismically active countries in the world. Since mid-XVI Century, a magnitude 8 or more earthquake has taken place every dozen of years, as an average. In the last 100 years, more than ten events with magnitudes around 8 or larger have taken place in this part of world. Three events with M>8 have taken place only in the last six years. The largest earthquake ever recorded took place in May, 1960, in <span class="hlt">southern</span> <span class="hlt">Chile</span>. Such extreme seismic activity is the result of the interaction of the Nazca, Antarctic, Scotia and South American plates in southwestern South America where <span class="hlt">Chile</span> is located. These megathrust earthquakes exhibit long rupture regions reaching several hundreds of km with fault displacements of several tens of meters. At least eighteen of these earthquakes have generated local tsunamis with runups larger than 4 m -including events in 2010, 2014 and 2015- therefore it is mandatory to establish a system with capabilities to rapidly evaluate the tsunamigenic potential of these events. In 2013, the newly created National Seismological Center (CSN) of the University of <span class="hlt">Chile</span> was tasked to upgrade the countrýs seismic network by increasing the numbers of real-time monitoring stations. The most important change to previous practices is the establishment of a GNSS network composed by 130 devices, in addition to the incorporation of 65 new collocated broadband and strong motion instruments. Additional 297 strong motion instruments for engineering purposes complement the system. Forty units -of the 130 devices- present an optional RTX capability, where satellite orbits and clock corrections are sent to the field device producing a 1-Hz position stream at 4-cm level. First records of ground displacement -using this technology-were recorded at the time of the largest aftershock (Mw=7.6) of the sequence that affected northern <span class="hlt">Chile</span> in 2014. The CSN is currently developing automatic detectors and amplitude estimators of displacement from the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995eso..pres....2.','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995eso..pres....2."><span>Eso's Situation in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p></p> <p>1995-02-01</p> <p>ESO, the European <span class="hlt">Southern</span> Observatory, in reply to questions raised by the international media, as well as an ongoing debate about the so-called "Paranal case" in Chilean newspapers, would like to make a number of related observations concerning its status and continued operation in that country [1]. THE ESO OBSERVATORY SITES IN <span class="hlt">CHILE</span> The European <span class="hlt">Southern</span> Observatory, an international organisation established and supported by eight European countries, has been operating more than 30 years in the Republic of <span class="hlt">Chile</span>. Here ESO maintains one of the world's prime astronomical observatories on the La Silla mountain in the <span class="hlt">southern</span> part of the Atacama desert. This location is in the Fourth Chilean Region, some 600 km north of Santiago de <span class="hlt">Chile</span>. In order to protect the La Silla site against dust and light pollution from possible future mining industries, roads and settlements, ESO early acquired the territory around this site. It totals about 825 sq. km and has effectively contributed to the preservation of its continued, excellent "astronomical" quality. Each year, more than 500 astronomers from European countries, <span class="hlt">Chile</span> and elsewhere profit from this when they come to La Silla to observe with one or more of the 15 telescopes now located there. In 1987, the ESO Council [2] decided to embark upon one of the most prestigious and technologically advanced projects ever conceived in astronomy, the Very Large Telescope (VLT). It will consist of four interconnected 8.2-metre telescopes and will become the largest optical telescope in the world when it is ready. It is safe to predict that many exciting discoveries will be made with this instrument, and it will undoubtedly play a very important role in our exploration of the distant universe and its many mysteries during the coming decades. THE VLT AND PARANAL In order to find the best site for the VLT, ESO performed a thorough investigation of many possible mountain tops, both near La Silla and in Northern <span class="hlt">Chile</span>. They showed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4713471','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4713471"><span>Influence of Biological Factors on Connectivity Patterns for Concholepas concholepas (loco) in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Garavelli, Lysel; Colas, François; Verley, Philippe; Kaplan, David Michael; Yannicelli, Beatriz; Lett, Christophe</p> <p>2016-01-01</p> <p>In marine benthic ecosystems, larval connectivity is a major process influencing the maintenance and distribution of invertebrate populations. Larval connectivity is a complex process to study as it is determined by several interacting factors. Here we use an individual-based, biophysical model, to disentangle the effects of such factors, namely larval vertical migration, larval growth, larval mortality, adults fecundity, and habitat availability, for the marine gastropod Concholepas concholepas (loco) in <span class="hlt">Chile</span>. Lower transport success and higher dispersal distances are observed including larval vertical migration in the model. We find an overall decrease in larval transport success to settlement areas from northern to <span class="hlt">southern</span> <span class="hlt">Chile</span>. This spatial gradient results from the combination of current direction and intensity, seawater temperature, and available habitat. From our simulated connectivity patterns we then identify subpopulations of loco along the Chilean coast, which could serve as a basis for spatial management of this resource in the future. PMID:26751574</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10384032','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10384032"><span>Hydrological and Oceanographic Considerations for Integrated Coastal <span class="hlt">Zone</span> Management in <span class="hlt">Southern</span> Belize.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Heyman; Kjerfve</p> <p>1999-09-01</p> <p>/ The objectives of this study are to: (1) characterize the meteorology and hydrology of the Maya Mountain-Marine Area Transect in <span class="hlt">southern</span> Belize, (2) employ a simple water balance model to examine the discharge rates of seven watersheds to Port Honduras, (3) test the validity of the hydrological model, (4) explore the implications of potential landscape and hydrological alterations, and (5) examine the value of protected areas. The <span class="hlt">southern</span> coastal portion of the study area is classified as wet tropical forest and the remainder as moist tropical forest. Rainfall is 3000-4000 mm annually. Resulting annual freshwater discharge directly into Port Honduras is calculated at 2.5 x 10(9) m3, a volume equal to the basin. During the rainy season, June-September, 84% of the annual discharge occurs, which causes the bay to become brackish. Port Honduras serves as an important nursery ground for many species of commercially important fish and shellfish. The removal of forest cover in the uplands, as a result of agriculture, aquaculture, and village development, is likely to significantly accelerate erosion. Increased erosion would reduce soil fertility in the uplands and negatively affect mangrove, seagrass, and coral reef productivity in the receiving coastal embayment. Alternatively, the conservation of an existing protected areas corridor, linking the Maya Mountains to the Caribbean Sea, is likely to enhance regional sustainable economic development. This study aims to support environmental management at the scale of the "ecoscape"-a sensible ecological unit of linked watersheds and coastal and marine environments.KEY WORDS: Ecosystem management; Coastal <span class="hlt">zone</span> management; Belize; Hydrologyhttp://link.springer-ny.com/link/service/journals/00267/bibs/24n2p229.html</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC21C0840K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC21C0840K"><span>Climate change and wildfire around <span class="hlt">southern</span> Africa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kimura, K.</p> <p>2013-12-01</p> <p>When the climate change in <span class="hlt">southern</span> Africa is analyzed, the effects of rainfall by Inter Tropical Convergence <span class="hlt">Zone</span>(ITCZ) and cyclone are important. In this study, the rainfall patterns are analyzed with synoptic analysis. The <span class="hlt">southern</span> limit of ITCZ is around the arid <span class="hlt">zone</span> around Namibia, Botswana, Zimbabwe and Mozambique. This <span class="hlt">zone</span> has some effects of both ITCZ and extratropical cyclones by season. As well as this, the eastern part of this area has heavy rainfall by the cyclone from the Indian Ocean once in several years. In the other hand, a lot of wildfire occurs in this area. The main cause of the wildfire is anthropogenic misbehavior of the fire by the slash-and-burn agriculture. Recently we can find the wildfire detected with the satellite imagery like Terra/Aqua MODIS. We can compare the weather environment and the wildfire occurrence with Geographical Information System. We have tried making the fire weather index suitable for the <span class="hlt">southern</span> African semi-arid area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3988865','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3988865"><span>Induced Abortion and Associated Factors in Health Facilities of Guraghe <span class="hlt">Zone</span>, <span class="hlt">Southern</span> Ethiopia</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hambisa, Mitiku Teshome; Semahegn, Agumasie</p> <p>2014-01-01</p> <p>Unsafe abortion is one of the major medical and public health problems in developing countries including Ethiopia. However, there is a lack of up-to-date and reliable information on induced abortion distribution and its determinant factors in the country. This study was intended to assess induced abortion and associated factors in health facilities of Guraghe <span class="hlt">zone</span>, <span class="hlt">Southern</span> Ethiopia. Institution based cross-sectional study was conducted in eight health facilities in Guraghe <span class="hlt">zone</span>. Client exit interview was conducted on 400 patients using a structured questionnaire. Bivariate and multivariate logistic regression analysis was performed to identify factors associated with induced abortion. Out of 400 women, 75.5% responded that the current pregnancy that ended in abortion is unwanted. However, only 12.3% of the respondents have admitted interference to the current pregnancy. Having more than four pregnancies (AOR = 4.28, CI: (1.24–14.71)), age of 30–34 years (AOR = 0.15, CI: (0.04–0.55)), primary education (AOR = 0.26, CI: (0.13–0.88)), and wanted pregnancy (AOR = 0.44, CI: (0.14–0.65)) were found to have association with induced abortion. The study revealed high level of induced abortion which is underpinned by high magnitude of unwanted pregnancy. There is requirement for widespread expansion of increased access to high quality family planning service and post-abortion care. PMID:24800079</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ctio.noao.edu/noao/content/Astro-Tourism-Chile','SCIGOVWS'); return false;" href="http://www.ctio.noao.edu/noao/content/Astro-Tourism-Chile"><span>Astro Tourism in <span class="hlt">Chile</span> | CTIO</span></a></p> <p><a target="_blank" href="http://www.science.gov/aboutsearch.html">Science.gov Websites</a></p> <p></p> <p></p> <p>Program PIA Program GO-FAAR Program Other Opportunities <em>Tourism</em> Visits to Tololo Astro <em>tourism</em> in <span class="hlt">Chile</span> <em>Tourism</em> in <span class="hlt">Chile</span> Information for travelers Visit Tololo Media Relations News Press Release Publications ‹› You are here CTIO Home » Outreach » <em>Tourism</em> » Astro <em>Tourism</em> in <span class="hlt">Chile</span> Astro <em>Tourism</em> in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JVGR..332..109N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JVGR..332..109N"><span>Holocene tephra succession of Puyehue-Cordón Caulle and Antillanca/Casablanca volcanic complexes, <span class="hlt">southern</span> Andes (40-41°S)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Naranjo, J. A.; Singer, B. S.; Jicha, B. R.; Moreno, H.; Lara, L. E.</p> <p>2017-02-01</p> <p>Puyehue-Cordón Caulle and Antillanca volcanic complexes are two of at least 50 active frontal arc volcanoes that define the 1400 km-long <span class="hlt">Southern</span> Volcanic <span class="hlt">Zone</span> of <span class="hlt">Chile</span>. Holocene tephra deposits in <span class="hlt">Chile</span> and Argentina (40-41°S) up to 100 km east of these volcanoes comprise at least five voluminous ( 1 to 8 km3) pyroclastic-fall layers that preceded several recently deposited Cordón Caulle pumice fallouts. Field observations of proximal, medium, and distal facies of the deposits, in conjunction with geochronology and geochemistry of the volcanic complexes, indicate that three fall layers are derived from Puyehue volcano (Puyehue 1 and 2, and Mil Hojas), whereas two are sourced from the Antillanca complex (Playas Blanca-Negra, and Nahuel Huapi Tephra), 20 km to the south. The oldest tephra (calibrated 14C age 10.49 ± 0.12 ka, 2σ), found only at medium-distal facies, is deposited directly on granitic moraine boulders and consists of deeply weathered, orange dacitic pumice lapilli. The next prominent tephra at 7 ka comprises dacitic pumice and its age is equivalent to a rhyodacitic dome exposed in the Puyehue summit crater. Above these deposits there are phases of a complex eruption consisting of a conspicuous compositionally-<span class="hlt">zoned</span> tephra. It also comprises a pyroclastic density current, together with lithic rich and scoriaceous fallout deposits. Mineralogical, geochemical, and Sr isotope evidence, plus the isopach maps, confirm that this sequence of eruptive events is sourced from Antillanca at 1932 ± 68 yrBP. The total volume of this eruptive sequence exceeds 8 km3, making it the largest Holocene eruption from either volcanic complex. This eruption was likely responsible for the destruction of an ancestral Antillanca volcano and the formation of a 4.5 km diameter caldera. A distinctive younger unit in the region is a voluminous rhyodacitic pumice fall (calibrated 14C age 1.11 ± 0.07 ka), above which a series of several alternating dark lithic and pumice</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S31B4397P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S31B4397P"><span>The Eastern Tennessee Seismic <span class="hlt">Zone</span>: Reactivation of an Ancient Continent-Continent Suture <span class="hlt">Zone</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Powell, C. A.</p> <p>2014-12-01</p> <p>The eastern Tennessee seismic <span class="hlt">zone</span> (ETSZ) may represent reactivation of an ancient shear <span class="hlt">zone</span> that accommodated left-lateral, transpressive motion of the Amazon craton during the Grenville orogeny. Several different lines of evidence support this concept including velocity models for the crust, earthquake hypocenter alignments, focal mechanism solutions, potential field anomalies, paleomagnetic pole positions, and isotopic geochemical studies. The ETSZ trends NE-SW for about 300 km and displays remarkable correlation with the prominent New York - Alabama (NY-AL) aeromagnetic lineament. Vp and Vs models for the crust derived from a local ETSZ earthquake tomography study reveal the presence of a narrow, NE-SW trending, steeply dipping <span class="hlt">zone</span> of low velocities that extends to a depth of at least 24 km and is associated with the vertical projection of the NY-AL aeromagnetic lineament. The low velocity <span class="hlt">zone</span> is interpreted as a major basement fault. The recent Mw 4.2 Perry County eastern Kentucky earthquake occurred north of the ETSZ but has a focal depth and mechanism that are similar to those for ETSZ earthquakes. We investigate the possibility that the proposed ancient shear <span class="hlt">zone</span> extends into eastern Kentucky using Bouguer and aeromagnetic maps. The <span class="hlt">southern</span> end of the ETSZ is characterized by hypocenters that align along planes dipping at roughly 45 degrees and focal mechanisms that contain large normal faulting components. The NY-AL aeromagnetic lineament also changes trend in the <span class="hlt">southern</span> end of the ETSZ and the exact location of the lineament is ambiguous. We suggest that the <span class="hlt">southern</span> portion of the ETSZ involves reactivation of reverse faults (now as normal faults) that mark the ancient transition between a collisional to a more transpressive boundary between Amazonia and Laurentia during the formation of the super continent Rodinia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3291571','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3291571"><span>Glaciation Effects on the Phylogeographic Structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae) in the <span class="hlt">Southern</span> Andes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Palma, R. Eduardo; Boric-Bargetto, Dusan; Torres-Pérez, Fernando; Hernández, Cristián E.; Yates, Terry L.</p> <p>2012-01-01</p> <p>The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in <span class="hlt">Chile</span> and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of <span class="hlt">Chile</span>, as well as in adjacent areas in <span class="hlt">southern</span> Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, Bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in <span class="hlt">Chile</span>: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000–13,000 years ago). Neutrality tests and the “g” parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in <span class="hlt">southern</span> Temperate Forests (and adjacent areas in Patagonia). From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean <span class="hlt">Chile</span> using glacial retreats. PMID:22396751</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22396751','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22396751"><span>Glaciation effects on the phylogeographic structure of Oligoryzomys longicaudatus (Rodentia: Sigmodontinae) in the <span class="hlt">southern</span> Andes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Palma, R Eduardo; Boric-Bargetto, Dusan; Torres-Pérez, Fernando; Hernández, Cristián E; Yates, Terry L</p> <p>2012-01-01</p> <p>The long-tailed pygmy rice rat Oligoryzomys longicaudatus (Sigmodontinae), the major reservoir of Hantavirus in <span class="hlt">Chile</span> and Patagonian Argentina, is widely distributed in the Mediterranean, Temperate and Patagonian Forests of <span class="hlt">Chile</span>, as well as in adjacent areas in <span class="hlt">southern</span> Argentina. We used molecular data to evaluate the effects of the last glacial event on the phylogeographic structure of this species. We examined if historical Pleistocene events had affected genetic variation and spatial distribution of this species along its distributional range. We sampled 223 individuals representing 47 localities along the species range, and sequenced the hypervariable domain I of the mtDNA control region. Aligned sequences were analyzed using haplotype network, bayesian population structure and demographic analyses. Analysis of population structure and the haplotype network inferred three genetic clusters along the distribution of O. longicaudatus that mostly agreed with the three major ecogeographic regions in <span class="hlt">Chile</span>: Mediterranean, Temperate Forests and Patagonian Forests. Bayesian Skyline Plots showed constant population sizes through time in all three clusters followed by an increase after and during the Last Glacial Maximum (LGM; between 26,000-13,000 years ago). Neutrality tests and the "g" parameter also suggest that populations of O. longicaudatus experienced demographic expansion across the species entire range. Past climate shifts have influenced population structure and lineage variation of O. longicaudatus. This species remained in refugia areas during Pleistocene times in <span class="hlt">southern</span> Temperate Forests (and adjacent areas in Patagonia). From these refugia, O. longicaudatus experienced demographic expansions into Patagonian Forests and central Mediterranean <span class="hlt">Chile</span> using glacial retreats.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002ASAJ..112.2334P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002ASAJ..112.2334P"><span>Ethnographic model of acoustic use of space in the <span class="hlt">southern</span> Andes for an archaeo-musicological investigation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perez de Arce, Jose</p> <p>2002-11-01</p> <p>Studies of ritual celebrations in central <span class="hlt">Chile</span> conducted in the past 15 years show that the spatial component of sound is a crucial component of the whole. The sonic compositions of these rituals generate complex musical structures that the author has termed ''multi-orchestral polyphonies.'' Their origins have been documented from archaeological remains in a vast region of <span class="hlt">southern</span> Andes (<span class="hlt">southern</span> Peru, Bolivia, northern Argentina, north-central <span class="hlt">Chile</span>). It consists of a combination of dance, space walk-through, spatial extension, multiple movements between listener and orchestra, and multiple relations between ritual and ambient sounds. The characteristics of these observables reveal a complex schematic relation between space and sound. This schema can be used as a valid hypothesis for the study of pre-Hispanic uses of acoustic ritual space. The acoustic features observed in this study are common in Andean ritual and, to some extent are seen in Mesoamerica as well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70186232','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70186232"><span>Evidence for late Holocene relative sea-level fall from reconnaissance stratigraphical studies in an area of earthquake-subsided intertidal deposits, Isla Chiloé, <span class="hlt">southern</span> <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Frostick, L.E.; Steel, R.J.; Bartsch-Winkler, S.; Schmoll, H.R.</p> <p>1993-01-01</p> <p>At Río Pudeto and Quetalmahue, two estuaries along the northern shore of Isla Chiloé that subsided as much as 2 m in the great 1960 earthquake, reconnaissance stratigraphical studies reveal evidence of a regressive, nearshore marine sequence. The intertidal deposits include a peat-bearing, high-intertidal marsh sequence as thick as 1.4 m overlying shell- and foraminifera-bearing silt and clay layers presumed to represent a deeper water, low-intertidal environment.Stratigraphy indicates a relative sea-level fall since about 5000 years BP as evidenced by radiocarbon ages that constrain the peat-bearing sequences. Locally, low-intertidal silt and clay overlie high-intertidal peat layers, but such minor transgressions cannot be correlated from site to site. At Río Pudeto, the youngest foraminifera-bearing silt deposit is no younger than 1200 years BP. The youngest age of shells at Quetalmahue is about 2600 years BP. The oldest peat-bearing deposits that are not overlain by silt deposits are about 1350 years BP at Río Pudeto, and as old as 4900 years BP at Quetalmahue. At Río Pudeto, peat-bearing deposits, which are overlain by silt and clay, range in age from 760 to 5430 years BP, and at Quetalmahue from 290 to 5290 years BP. A beach terrace on the northwest coast of the Isla is estimated to have been emergent since 1150 + 130 years ago.Although some relatively abrupt transgressions may be due to sudden coseismic subsidence, data are not sufficient to document regional subsidence during individual plate-interface earthquakes. Seven earthquakes in south central <span class="hlt">Chile</span> since 1520, especially those that occurred in 1575, 1737, and 1837, are thought to have been of a magnitude comparable to that of the 1960 earthquake. Although the sedimentological effects of the 1960 earthquake on the intertidal <span class="hlt">zone</span> were dramatic, only limited evidence of possible historic earthquakes is found on Isla Chiloé and nearby islands; the ages and displacements of these earthquakes are</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25417727','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25417727"><span>Genetic and antigenic diversity of Theileria parva in cattle in Eastern and <span class="hlt">Southern</span> <span class="hlt">zones</span> of Tanzania. A study to support control of East Coast fever.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Elisa, Mwega; Hasan, Salih Dia; Moses, Njahira; Elpidius, Rukambile; Skilton, Robert; Gwakisa, Paul</p> <p>2015-04-01</p> <p>This study investigated the genetic and antigenic diversity of Theileria parva in cattle from the Eastern and <span class="hlt">Southern</span> <span class="hlt">zones</span> of Tanzania. Thirty-nine (62%) positive samples were genotyped using 14 mini- and microsatellite markers with coverage of all four T. parva chromosomes. Wright's F index (F(ST) = 0 × 094) indicated a high level of panmixis. Linkage equilibrium was observed in the two <span class="hlt">zones</span> studied, suggesting existence of a panmyctic population. In addition, sequence analysis of CD8+ T-cell target antigen genes Tp1 revealed a single protein sequence in all samples analysed, which is also present in the T. parva Muguga strain, which is a component of the FAO1 vaccine. All Tp2 epitope sequences were identical to those in the T. parva Muguga strain, except for one variant of a Tp2 epitope, which is found in T. parva Kiambu 5 strain, also a component the FAO1 vaccine. Neighbour joining tree of the nucleotide sequences of Tp2 showed clustering according to geographical origin. Our results show low genetic and antigenic diversity of T. parva within the populations analysed. This has very important implications for the development of sustainable control measures for T. parva in Eastern and <span class="hlt">Southern</span> <span class="hlt">zones</span> of Tanzania, where East Coast fever is endemic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19374470','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19374470"><span>Alloxenic distribution of cystacanths of two Profilicollis species in sympatric crustacean hosts in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Balboa, L; Hinojosa, A; Riquelme, C; Rodríguez, S; Bustos, J; George-Nascimento, M</p> <p>2009-10-01</p> <p>The taxonomic status of Profilicollis ( = Falsifilicollis Webster, 1948) species in crustaceans in <span class="hlt">Chile</span> is examined. Mole crabs, Emerita analoga (Stimpson 1857), living in the splash <span class="hlt">zone</span> of a sandy beach at Lenga off the coast of central <span class="hlt">Chile</span>, harbor Polymorphus (Profilicollis) bullocki Mateo, Córdova and Guzmán 1982, while the estuarine crabs, Hemigrapsus crenulatus (Milne-Edwards, 1837), living in an oligohaline inlet at the same site, harbor Profilicollis spp. cystacanths which cannot be distinguished specifically to either Profilicollis antarcticus or P. chasmagnathi Holcman-Spector, Mañé-Garzón and Dei-Cas 1977. We found no morphological data supporting records of P. altmani along the coast of <span class="hlt">Chile</span>. Therefore, and after examination of both their morphology and the literature, we consider that P. bullocki must be reinstated as a valid species in the genus. There is a widespread distribution of habitats, such as sandy beaches and inlets, as well as a variety of host taxa involved in the life cycle of Profilicollis spp. Consequently, they provide an interesting scenario for testing hypotheses regarding the coevolution and host specificity of these parasites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1464119','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1464119"><span>Farmers' perception on the importance of variegated grasshopper (Zonocerus variegatus (L.)) in the agricultural production systems of the humid forest <span class="hlt">zone</span> of <span class="hlt">Southern</span> Cameroon</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kekeunou, Sévilor; Weise, Stephan; Messi, Jean; Tamò, Manuel</p> <p>2006-01-01</p> <p>Background Zonocerus variegatus (Linnaeus, 1758) (Orthoptera: Pyrgomorphidae) is known as an agricultural pest in West and Central Africa. However, its importance in the agricultural production system in Cameroon has not been investigated. The study assesses farmers' perception on the importance of Z. variegatus in the agricultural production systems of the humid forest <span class="hlt">zone</span> of <span class="hlt">Southern</span> Cameroon. Methods Research was carried out in 5 villages of each of three Agro-Ecological, Cultural and Demographic Blocks (AECD-Blocks) of the Forest Margin Benchmark Area (FMBA). In each village, a semi-structured survey was used; male and female groups of farmers were interviewed separately. Results Z. variegatus is present throughout the humid forest <span class="hlt">zone</span> of <span class="hlt">Southern</span> Cameroon, where it is ranked as the third most economically important insect pest of agriculture. In the farmers' opinion, Z. variegatus is a polyphagous insect with little impact on young perennial crops. The length of the pre-farming fallow does not affect Z. variegatus pest pressure in the following crops. The increased impact of the grasshopper observed today in the fields, compared to what existed 10 years ago is as a result of deforestation and increase in surface of herbaceous fallow. The damage caused by Z. variegatus is higher in fields adjacent to C. odorata and herbaceous fallows than in those adjacent to forests and shrubby fallows. The fight against this grasshopper is often done through physical methods carried out by hand, for human consumption. The farmers highlight low usage of the chemical methods and a total absence of biological and ecological methods. Conclusion Farmers' perception have contributed to understanding the status of Z. variegatus in the humid forest <span class="hlt">zone</span> of <span class="hlt">Southern</span> Cameroon. The results are in general similar to those obtained in other countries. PMID:16573815</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015DokES.464.1033N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015DokES.464.1033N"><span>Influence of frontal <span class="hlt">zones</span> on the distribution of particulate matter and organic compounds in surface waters of the Atlantic and <span class="hlt">Southern</span> Oceans</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nemirovskaya, I. A.; Lisitzin, A. P.; Kravchishina, M. D.; Redzhepova, Z. Yu.</p> <p>2015-10-01</p> <p>Particulate matter and organic compounds (chlorophyll, lipids, and hydrocarbons) were analyzed in surface waters along the routes of R/Vs Akademik Fedorov (cruise 32) and Akademik Treshnikov (cruise 2) in February-May of 2012 and 2014, respectively, in the course of the 57th and 59th Russian Antarctic expeditions. It was found that the frontal <span class="hlt">zones</span> exert the primary influence on the concentrations of the mentioned components in the <span class="hlt">Southern</span> Ocean and in the western part of the Atlantic Ocean. The supply of pollutants into the Eastern Atlantic Ocean on the shelf of the Iberian peninsula results in a pronounced increase in the concentrations of lipids and hydrocarbons causing local anthropogenic pollution <span class="hlt">zones</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.G32A..05E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.G32A..05E"><span>Geological Evidence of Predecessors to the 2010 Earthquake and Tsunami in South-Central <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ely, L. L.; Cisternas, M.; Wesson, R. L.; Lagos, M.</p> <p>2010-12-01</p> <p> layers show temporal overlap with the 1835 earthquake to the north and a large earthquake in <span class="hlt">southern</span> <span class="hlt">Chile</span> in AD 1575, which previous research indicates was similar in character and latitudinal extent to the 1960 earthquake. The stratigraphic units dividing the four sand layers repeatedly exhibit a pattern of a basal brownish silty peat that grades upwards to grayish less organic silt and a sharp contact with the next overlying sand layer. We interpret this pattern as possible evidence of coseismic uplift out of the tidal <span class="hlt">zone</span>, followed by interseismic subsidence. By virtue of its marginal location between historic earthquake rupture <span class="hlt">zones</span>, the site at Tirua could selectively preserve evidence of the largest earthquakes and tsunamis produced in the 1960 rupture area to the south and the 2010 rupture area to the north.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPA13A3898C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPA13A3898C"><span>The Importance of <span class="hlt">Southern</span> Hemisphere CZOs for Evaluating Spatial Patterns of Chemical Structure in the Critical <span class="hlt">Zone</span> and Assisting Human Development</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chadwick, O.</p> <p>2014-12-01</p> <p>The US Critical <span class="hlt">Zone</span> Exploration Network (CZEN) is a network of sites designed to provide a better understanding of the integrated Earth surface system. The capacity of the critical <span class="hlt">zone</span> to withstand perturbations, whether driven by climate, land use change, or spread of invasive species, depends on its chemical composition and physical state, which in turn depends on the time evolution of the critical <span class="hlt">zone</span>. Many temperate and/or tectonically active critical <span class="hlt">zones</span> contain a relatively short history due to rapid erosion but tectonically quiescent, tropical regions of the planet contain much longer records that need to be understood to cover the full suite of critical <span class="hlt">zone</span> processes. <span class="hlt">Southern</span> Hemisphere Critical <span class="hlt">Zone</span> Observatories such as those proposed for Kruger National Park (KNP) in South Africa and for portions of the Yilgarn Craton in Western Australa will allow us to extend our temporal understanding of development of spatial heterogeneity in the chemical and physical structure of the critical <span class="hlt">zone</span>. In addition to considering Earth and climate boundary conditions, these sites incorporate the roles that humans play in driving critical <span class="hlt">zone</span> processes. For instance along the edges of KNP there is strong evidence of soil erosions due to periurbanization and small-scale agriculture. The existence of KNP provides an important contrast between a "natural" and "human-dominated" landscape that can be exploited to evaluate human impacts on critical <span class="hlt">zone</span> resources and to develop targeted mitigation strategies. Western Australia has an exploitive economy that relies on large-scale agriculture and mineral extraction, both are intensive users of water which is scarce. The proposed CZO there will be partly focused on managing water under intense economic pressures. It is evident that if funding can be found for these sites they will enhance both critical <span class="hlt">zone</span> science and practical applied science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRB..122.3648C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRB..122.3648C"><span>Source of the 1730 Chilean earthquake from historical records: Implications for the future tsunami hazard on the coast of Metropolitan <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carvajal, M.; Cisternas, M.; Catalán, P. A.</p> <p>2017-05-01</p> <p>Historical records of an earthquake that occurred in 1730 affecting Metropolitan <span class="hlt">Chile</span> provide essential clues on the source characteristics for the future earthquakes in the region. The earthquake and tsunami of 1730 have been recognized as the largest to occur in Metropolitan <span class="hlt">Chile</span> since the beginning of written history. The earthquake destroyed buildings along >1000 km of the coast and produced a large tsunami that caused damage as far as Japan. Here its source characteristics are inferred by comparing local tsunami inundations computed from hypothetical earthquakes with varying magnitude and depth, with those inferred from historical observations. It is found that a 600-800 km long rupture involving average slip amounts of 10-14 m (Mw 9.1-9.3) best explains the observed tsunami heights and inundations. This large earthquake magnitude is supported by the 1730 tsunami heights inferred in Japan. The inundation results combined with local uplift reports suggest a southward increase of the slip depth along the rupture <span class="hlt">zone</span> of the 1730 earthquake. While shallow slip on the area to the north of the 2010 earthquake rupture <span class="hlt">zone</span> is required to explain the reported inundation, only deeper slip at this area can explain the coastal uplift reports. Since the later earthquakes of the region involved little or no slip at shallow depths, the near-future earthquakes on Metropolitan <span class="hlt">Chile</span> could release the shallow slip accumulated since 1730 and thus lead to strong tsunami excitation. Moderate shaking from a shallow earthquake could delay tsunami evacuation for the most populated coastal region of <span class="hlt">Chile</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011EOSTr..92...55P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011EOSTr..92...55P"><span>Understanding the South Pacific Convergence <span class="hlt">Zone</span> and Its Impacts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Power, Scott</p> <p>2011-02-01</p> <p>International Workshop on the South Pacific Convergence <span class="hlt">Zone</span>; Apia, Samoa, 24-26 August 2010 ; During the <span class="hlt">Southern</span> Hemisphere summer the South Pacific Convergence <span class="hlt">Zone</span> (SPCZ) in the southwestern Pacific Ocean produces the largest rainfall band in the world. The SPCZ tends to move northeast during <span class="hlt">southern</span> winter and El Niño and move southwest during <span class="hlt">southern</span> summer and La Niña. These changes in position have a profound influence on climate (e.g., rainfall, winds, and tropical cyclone frequencies) and life in most of the nations in the southwestern Pacific. Despite the importance of the SPCZ to the region and its prominence in the general circulation of the <span class="hlt">Southern</span> Hemisphere, the SPCZ has been studied relatively little compared with convergence <span class="hlt">zones</span> in the Northern Hemisphere. An international workshop on the SPCZ was held in Samoa and brought together 30 experts from Australia, the Cook Islands, Fiji, France, India, New Caledonia, New Zealand, Samoa, the Solomon Islands, Tonga, Tuvalu, the United Kingdom, the United States, and Vanuatu.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26627690','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26627690"><span>Prevalence of camel trypanosomosis (surra) and associated risk factors in Borena <span class="hlt">zone</span>, <span class="hlt">southern</span> Ethiopia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Olani, Abebe; Habtamu, Yitbarek; Wegayehu, Teklu; Anberber, Manyazewal</p> <p>2016-03-01</p> <p>A study was made to determine the prevalence of camel trypanosomosis (surra) and its associated risk factors in Borena <span class="hlt">zone</span>, <span class="hlt">southern</span> Ethiopia during 2013-2014. A total of 2400 blood samples were collected and examined by the buffy coat and thin blood film laboratory methods, and data were analyzed using the SPSS statistical software. The overall prevalence of camel trypanosomosis in the area was found to be 2.33 %. Prevalence was significantly different among the surveyed districts (P = 0.000), the pastoral associations (F = 6.408, P = 0.000), altitudinal divisions (P = 0.000), age groups (P = 0.034), and between animals possessing packed cell volume (PCV) values greater than 25 % and less than 25 % (P = 0.000); whereas, prevalence of the disease was not statistically significantly different between the sexes (P = 0.311) and among the body condition score groups (P = 0.739). The PCV of trypanosome positive and trypanosome negative camels differ significantly (P = 0.001), and prevalence of trypanosomosis was seen to be negatively correlated with packed cell volume (r = -0.069, P = 0.000) revealing the effect of camel trypanosomosis on anemia state of parasitized animals. In conclusion, camel trypanosomosis is a serious and economically important disease hampering camel production and productivity in <span class="hlt">southern</span> Ethiopia. Further studies involving more sensitive molecular techniques to reveal the precise magnitude of the disease and to identify the vector species of the parasite are recommended.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24362316','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24362316"><span>Using stated preference methods to design cost-effective subsidy programs to induce technology adoption: an application to a stove program in <span class="hlt">southern</span> <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gómez, Walter; Salgado, Hugo; Vásquez, Felipe; Chávez, Carlos</p> <p>2014-01-01</p> <p>We study the design of an economic incentive based program - a subsidy - to induce adoption of more efficient technology in a pollution reduction program in <span class="hlt">southern</span> <span class="hlt">Chile</span>. Stated preferences methods, contingent valuation (CV), and choice experiment (CE) are used to estimate the probability of adoption and the willingness to share the cost of a new technology by a household. The cost-effectiveness property of different subsidy schemes is explored numerically for different regulatory objectives. Our results suggest that households are willing to participate in voluntary programs and to contribute by paying a share of the cost of adopting more efficient technologies. We find that attributes of the existing and the new technology, beyond the price, are relevant determinant factors of the participation decision and payment. Limited access to credit markets for low income families can be a major barrier for an effective implementation of these types of programs. Variations in the design of the subsidy and on the regulator's objective and constraints can have significant impact on the level and the cost of reduction of aggregate emissions achieved. Copyright © 2013 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title27-vol1/pdf/CFR-2013-title27-vol1-sec9-154.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title27-vol1/pdf/CFR-2013-title27-vol1-sec9-154.pdf"><span>27 CFR 9.154 - <span class="hlt">Chiles</span> Valley.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-04-01</p> <p>... <span class="hlt">Chiles</span> Valley. (a) Name. The name of the viticultural area described in this section is “<span class="hlt">Chiles</span> Valley... viticultural area are four 1:24,000 Scale U.S.G.S. topography maps. They are titled: (1) St. Helena, CA 1960 photorevised 1980; (2) Rutherford, CA 1951 photorevised 1968; (3) <span class="hlt">Chiles</span> Valley, CA 1958 photorevised 1980; (4...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27166570','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27166570"><span>Crustacean communities in coastal ephemeral pools in the Araucanía region (38° S, <span class="hlt">Chile</span>).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>De Los Ríos-Escalante, P; Acevedo, P</p> <p>2016-01-01</p> <p>The fauna communities of ephemeral pools in <span class="hlt">southern</span> <span class="hlt">Chile</span> are characterized by heterogeneity of crustacean taxa; nevertheless, no detailed studies exist of their community structure. The aim of the present study was to analyze the crustacean community structure in two groups of ephemeral pools (Puaucho and Nigue pools) in the coastal <span class="hlt">zone</span> of the Araucanía region. A correlation matrix was made by species abundance against temperature, conductivity, pH and total dissolved solids. In a second step, a null model for species co-occurrence was applied to the total data and to each group. The results for total data revealed a significant direct relation between the abundance of H. costera, C. dubia and Mesocyclops. For the Puaucho pools, the same results were found together with direct associations with total dissolved solids, conductivity and pH. Finally, different results were found for the Nigue pools, with no clear significant associations, either direct or indirect, between the abundance of different crustacean taxa and abiotic parameters. These results were supported by the co-occurrence null model analysis, which revealed the presence of regulator factors for the total data, and for each of the two groups. Ecological topics are discussed with emphasis on meta-community dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AtmEn.161..221Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AtmEn.161..221Y"><span>Urban airborne matter in central and <span class="hlt">southern</span> <span class="hlt">Chile</span>: Effects of meteorological conditions on fine and coarse particulate matter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yáñez, Marco A.; Baettig, Ricardo; Cornejo, Jorge; Zamudio, Francisco; Guajardo, Jorge; Fica, Rodrigo</p> <p>2017-07-01</p> <p>Air pollution is one of the major global environmental problems affecting human health and life quality. Many cities of <span class="hlt">Chile</span> are heavily polluted with PM2.5 and PM10, mainly in the cold season, and there is little understanding of how the variation in particle matter differs between cities and how this is affected by the meteorological conditions. The objective of this study was to assess the effect of meteorological variables on respirable particulate matter (PM) of the main cities in the central-south valley of <span class="hlt">Chile</span> during the cold season (May to August) between 2014 and 2016. We used hourly PM2.5 and PMcoarse (PM10- PM2.5) information along with wind speed, temperature and relative humidity, and other variables derived from meteorological parameters. Generalized additive models (GAMs) were fitted for each of the eight cities selected, covering a latitudinal range of 929 km, from Santiago to Osorno. Great variation in PM was found between cities during the cold months, and that variation exhibited a marked latitudinal pattern. Overall, the more northerly cities tended to be less polluted in PM2.5 and more polluted in PMcoarse than the more southerly cities, and vice versa. The results show that other derived variables from meteorology were better related with PM than the use of traditional daily means. The main variables selected with regard to PM2.5 content were mean wind speed and minimum temperature (negative relationship). Otherwise, the main variables selected with regard to PMcoarse content were mean wind speed (negative), and the daily range in temperature (positive). Variables derived from relative humidity contributed differently to the models, having a higher effect on PMcoarse than PM2.5, and exhibiting both negative and positive effects. For the different cities the deviance explained by the GAMs ranged from 37.6 to 79.1% for PM2.5 and from 18.5 to 63.7% for PMcoarse. The percentage of deviance explained by the models for PM2.5 exhibited a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1814108V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1814108V"><span>Biogeochemical characteristics of mesoscale eddies in the generation <span class="hlt">zone</span> off Valparaíso, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Villegas, Valerie; Cornejo, Marcela; Molina, Verónica; Silva, Nelson; Hormazábal, Samuel</p> <p>2016-04-01</p> <p>The coastal area off Valparaiso is characterized by an intense mesoscale activity associated with eddies, which transport highly productive-coastal waters to the oligotrophic areas of the Subtropical Gyre. Among these, the Intrathermocline Anticyclonic Eddies (ITE's) which are forming in the eastern South Pacific, transport low oxygen- and high nutrients- subsurface water of Equatorial Subsurface Water (ESSW). These eddies have been well characterized in terms of generation rate, direction, speed and water transport. However, biogeochemical conditions in their origin and its temporal variability are not well assessed. The present study aims to determine the variability, spatially and temporally, of the biogeochemical properties in the water column at the eddies generation <span class="hlt">zone</span>, off Punta Ángeles, Valparaíso (33° S). For this, a monthly time series was conducted between January and August 2016 where a cross-shore transect with six-stations was deployed (from coast to 16 nm). Each station was sampled with CTD-OF, while only in station 5 (1300 m depth) was sampled in 16 depth for biogeochemical variables: nutrients (NO3-, NO2-, PO4-3, Si(OH)4), greenhouse gases (CO2, CH4 and N2O), chlorophyll a, stable isotopes in particulate organic material (13C, 15N), content of organic carbon and nitrogen in POM. The spatial and temporal distribution shows the presence of subsurface cores (100 - 300 m) with water with high salinity (> 34.7 psu) and low oxygen content (< 0.5 mLṡL-1), associated with mesoscale subsurface structures. The largest vertical and horizontal extension of these structures was observed in January 2015. These subsurface structures showed a significant deficit of reactive nitrogen (N* < -10 μM), nitrite accumulation (> 0.6 μM) and the highest supersaturations of CO2 (110 - 344%) and N2O (107 - 407%). Along with this, the eddies generation <span class="hlt">zone</span> presented a temporal variability of air-sea gases fluxes with the highest in the austral summer and autumn</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015BGD....12.6003S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015BGD....12.6003S"><span>Inter-decadal changes in the intensity of the Oxygen Minimum <span class="hlt">Zone</span> off Concepción, <span class="hlt">Chile</span> (~ 36° S) over the last century</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Srain, B.; Pantoja, S.; Sepúlveda, J.; Lange, C. B.; Muñoz, P.; Summons, R. E.; McKay, J.; Salamanca, M.</p> <p>2015-04-01</p> <p>We reconstructed oxygenation changes in the Oxygen Minimum <span class="hlt">Zone</span> of the upwelling ecosystem off Concepción (36° S), <span class="hlt">Chile</span>, using inorganic and organic proxies in a sediment core covering the last ca. 110 years of sedimentation in this area. Authigenic enrichments of Mo, U and Cd were observed between ca. 1935-1971 CE indicating a prolonged period of more reduced conditions in bottom waters and surface sediments. Significant positive correlations (p < 0.05; Spearman) between redox sensitive metals, algal sterols, biomarkers of anaerobic microorganisms, and archaeal glycerol dialkyl glycerol tetraether indicated a coupling among bottom water oxygen depletion, and increased primary and export production, suggesting that the period with low O2 of ca. 35 years, follows low frequency inter-decadal variation of the Pacific Decadal Oscillation, which may have resulted in O2 depletion over the entire continental shelf off Concepción. Taken together with the concurrent increase in sedimentary molecular indicators of anaerobic microbes allow us to suggest that the prokaryote community has been influenced by changes in oxygenation of the water column.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22012396','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22012396"><span>The role of dyking and fault control in the rapid onset of eruption at Chaitén volcano, <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wicks, Charles; de la Llera, Juan Carlos; Lara, Luis E; Lowenstern, Jacob</p> <p>2011-10-19</p> <p>Rhyolite is the most viscous of liquid magmas, so it was surprising that on 2 May 2008 at Chaitén Volcano, located in <span class="hlt">Chile</span>'s <span class="hlt">southern</span> Andean volcanic <span class="hlt">zone</span>, rhyolitic magma migrated from more than 5 km depth in less than 4 hours (ref. 1) and erupted explosively with only two days of detected precursory seismic activity. The last major rhyolite eruption before that at Chaitén was the largest volcanic eruption in the twentieth century, at Novarupta volcano, Alaska, in 1912. Because of the historically rare and explosive nature of rhyolite eruptions and because of the surprisingly short warning before the eruption of the Chaitén volcano, any information about the workings of the magmatic system at Chaitén, and rhyolitic systems in general, is important from both the scientific and hazard perspectives. Here we present surface deformation data related to the Chaitén eruption based on radar interferometry observations from the Japan Aerospace Exploration Agency (JAXA) DAICHI (ALOS) satellite. The data on this explosive rhyolite eruption indicate that the rapid ascent of rhyolite occurred through dyking and that melt segregation and magma storage were controlled by existing faults.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25383987','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25383987"><span>Distribution and growth of Vibrio parahaemolyticus in <span class="hlt">southern</span> Chilean clams (Venus antiqua) and blue mussels (Mytilus chilensis).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Aranda, Carlos P; Yévenes, Marco; Rodriguez-Benito, Cristina; Godoy, Félix A; Ruiz, Magdalena; Cachicas, Viviana</p> <p>2015-01-01</p> <p>We evaluated the distribution and growth of Vibrio parahaemolyticus in the inland sea of <span class="hlt">southern</span> <span class="hlt">Chile</span>, where the world's largest foodborne gastroenteritis outbreak by the pandemic strain O3:K6 occurred in 2005. Intertidal samples of Mytilus chilensis and Venus antiqua were collected around port towns between 41°28'S and 43°07'S, during April to May 2011 and January to March 2012. We used most probable number real-time polymerase chain reaction (MPN-PCR) for enumeration of the tlh, tdh, and trh genes in freshly harvested bivalves and after a controlled postharvest temperature abuse. Pathogenic markers (tdh+ or trh+) were not detected. Total V. parahaemolyticus (tlh+) in freshly harvested samples reached up to 0.38 and 3.66 log MPN/g in 2011 and 2012, respectively, with values close to or above 3 log MPN/g only near Puerto Montt (41°28'S, 72°55'W). Enrichments by temperature abuse (>2 log MPN/g) occurred mainly in the same <span class="hlt">zone</span>, regardless of the year, suggesting that both natural or anthropogenic exposure to high temperatures were more critical. Lower salinity and higher sea surface temperature in Reloncaví Sound and Reloncaví Estuary were consistent with our observations and allowed confirmation of the existence of a high-risk <span class="hlt">zone</span> near Puerto Montt. Based on the results, a strategy focused on risk management inside this defined hazard <span class="hlt">zone</span> is recommended.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.eia.gov/beta/international/analysis.cfm?iso=CHL','EIAPUBS'); return false;" href="https://www.eia.gov/beta/international/analysis.cfm?iso=CHL"><span><span class="hlt">Chile</span> Country Analysis Brief</span></a></p> <p><a target="_blank" href="http://www.eia.doe.gov/reports/">EIA Publications</a></p> <p></p> <p>2016-01-01</p> <p><span class="hlt">Chile</span> is the only member of the Organization of Economic Cooperation and Development (OECD) in South America. It is the fifth-largest consumer of energy on the continent, but unlike most other large economies in the region, it is only a minor producer of fossil fuels. Therefore, <span class="hlt">Chile</span> is heavily dependent on energy imports.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA124646','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA124646"><span>Area Handbook Series: <span class="hlt">Chile</span>: A Country Study</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1982-05-01</p> <p>de Educaci6n en <span class="hlt">Chile</span> a Partir de 1973." (Paper presented at workshop "Six...34Salud en <span class="hlt">Chile</span> : El Problema de Fondo," Mensaje [Santiago], 28, No. 282, September 1979, 558-66. Goldrich, Daniel, Raymond B. Pratt, and C. R. Schuller...Transforma- ciones del Sistema de Ateni6n M6dica en <span class="hlt">Chile</span> ." (Paper pre- sented at workshop "Six Years of Military Rule in <span class="hlt">Chile</span> ," sponsored by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S34B..08H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S34B..08H"><span>Continuing Megathrust Earthquake Potential in northern <span class="hlt">Chile</span> after the 2014 Iquique Earthquake Sequence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hayes, G. P.; Herman, M. W.; Barnhart, W. D.; Furlong, K. P.; Riquelme, S.; Benz, H.; Bergman, E.; Barrientos, S. E.; Earle, P. S.; Samsonov, S. V.</p> <p>2014-12-01</p> <p>The seismic gap theory, which identifies regions of elevated hazard based on a lack of recent seismicity in comparison to other portions of a fault, has successfully explained past earthquakes and is useful for qualitatively describing where future large earthquakes might occur. A large earthquake had been expected in the subduction <span class="hlt">zone</span> adjacent to northern <span class="hlt">Chile</span>, which until recently had not ruptured in a megathrust earthquake since a M~8.8 event in 1877. On April 1 2014, a M 8.2 earthquake occurred within this northern <span class="hlt">Chile</span> seismic gap, offshore of the city of Iquique; the size and spatial extent of the rupture indicate it was not the earthquake that had been anticipated. Here, we present a rapid assessment of the seismotectonics of the March-April 2014 seismic sequence offshore northern <span class="hlt">Chile</span>, including analyses of earthquake (fore- and aftershock) relocations, moment tensors, finite fault models, moment deficit calculations, and cumulative Coulomb stress transfer calculations over the duration of the sequence. This ensemble of information allows us to place the current sequence within the context of historic seismicity in the region, and to assess areas of remaining and/or elevated hazard. Our results indicate that while accumulated strain has been released for a portion of the northern <span class="hlt">Chile</span> seismic gap, significant sections have not ruptured in almost 150 years. These observations suggest that large-to-great sized megathrust earthquakes will occur north and south of the 2014 Iquique sequence sooner than might be expected had the 2014 events ruptured the entire seismic gap.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JSAES..48...43T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JSAES..48...43T"><span>A new interpretation for the interference <span class="hlt">zone</span> between the <span class="hlt">southern</span> Brasília belt and the central Ribeira belt, SE Brazil</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trouw, Rudolph A. J.; Peternel, Rodrigo; Ribeiro, Andre; Heilbron, Mônica; Vinagre, Rodrigo; Duffles, Patrícia; Trouw, Camilo C.; Fontainha, Marcos; Kussama, Hugo H.</p> <p>2013-12-01</p> <p>In southeastern Brazil, the Neoproterozoic NNW-SSE trending <span class="hlt">southern</span> Brasília belt is apparently truncated by the ENE-WSW central Ribeira belt. Different interpretations in the literature of the transition between these two belts motivated detailed mapping and additional age dating along the contact <span class="hlt">zone</span>. The result is a new interpretation presented in this paper. The <span class="hlt">southern</span> Brasília belt resulted from E-W collision between the active margin of the Paranapanema paleocontinent, on the western side, now forming the Socorro-Guaxupé Nappe, with the passive margin of the São Francisco paleocontinent on the eastern side. The collision produced an east vergent nappe stack, the Andrelândia Nappe System, along the suture. At its <span class="hlt">southern</span> extreme the Brasília belt was thought to be cut off by a shear <span class="hlt">zone</span>, the "Rio Jaguari mylonites", at the contact with the Embu terrane, pertaining to the Central Ribeira belt. Our detailed mapping revealed that the transition between the Socorro-Guaxupé Nappe (Brasília belt) and the Embu terrane (Ribeira belt) is not a fault but rather a gradational transition that does not strictly coincide with the Rio Jaguari mylonites. A typical Cordilleran type magmatic arc batholith of the Socorro-Guaxupé Nappe with an age of ca. 640 Ma intrudes biotite schists of the Embu terrane and the age of zircon grains from three samples of metasedimentary rocks, one to the south, one to the north and one along the mylonite <span class="hlt">zone</span>, show a similar pattern of derivation from a Rhyacian source area with rims of 670-600 Ma interpreted as metamorphic overgrowth. We dated by LA-MC-ICPMS laser ablation (U-Pb) zircon grains from a calc-alkaline granite, the Serra do Quebra-Cangalha Batholith, located within the Embu terrane at a distance of about 40 km south of the contact with the Socorro Nappe, yielding an age of 680 ± 13 Ma. This age indicates that the Embu terrane was part of the upper plate (Socorro-Guaxupé Nappe) by this time. Detailed mapping</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.S44C..02A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.S44C..02A"><span>Seismological and Geodynamic Monitoring Network in the "javakheti" Test <span class="hlt">Zone</span> in the <span class="hlt">Southern</span> Caucasus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arakelyan, A.; Babayan, H.; Karakhanyan, A.; Durgaryan, R.; Basilaia, G.; Sokhadze, G.; Bidzinashvili, G.</p> <p>2012-12-01</p> <p>The Javakheti Highland located in the border region between Armenia and Georgia (sharing a border with Turkey) is an area in the <span class="hlt">Southern</span> Caucasus of young Holocene-Quaternary volcanism and a region with convergence of a number of active faults. Issues related to the geometry, kinematics and slip-rate of these faults and assessment of their seismic hazard remain unclear in part due to the fragmentary nature of the studies carried out soley within the borders of each of the countries as opposed to region wide. In the frame of the ISTC A-1418 Project "Open network of scientific Centers for mitigation risk of natural hazards in the <span class="hlt">Southern</span> Caucasus and Central Asia" the Javakheti Highland was selected as a trans-border test-<span class="hlt">zone</span>. This designation allowed for the expansion and upgrading of the seismological and geodynamic monitoring networks under the auspices of several international projects (ISTC CSP-053 Project "Development of Communication System for seismic hazard situations in the <span class="hlt">Southern</span> Caucasus and Central Asia", NATO SfP- 983284 Project "Caucasus Seismic Emergency Response") as well as through joint research programs with the National Taiwan University and Institute of Earth Sciences (IES, Taiwan), Universite Montpellier II (France) and Ecole et Observatoire des Sciences de la Terre-Université de Strasbourg (France). Studies of geodynamic processes, and seismicity of the region and their interaction have been carried out utilizing the newly established seismological and geodynamic monitoring networks and have served as a basis for the study of the geologic and tectonic structure . Upgrading and expansion of seismological and geodynamic networks required urgent solutions to the following tasks: Introduction of efficient online systems for information acquisition, accumulation and transmission (including sattelite systems) from permanent and temporary installed stations, Adoption of international standards for organization and management of databases in GIS</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015BGD....12.3057E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015BGD....12.3057E"><span>Growth and production of the copepod community in the <span class="hlt">southern</span> area of the Humboldt Current System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Escribano, R.; Bustos-Ríos, E.; Hidalgo, P.; Morales, C. E.</p> <p>2015-02-01</p> <p>Zooplankton production is a critical issue for understanding marine ecosystem structure and dynamics, however, its time-space variations are mostly unknown in most systems. In this study, estimates of copepod growth and production (CP) in the coastal upwelling and coastal transition <span class="hlt">zones</span> off central-<span class="hlt">southern</span> <span class="hlt">Chile</span> (∼35-37° S) were obtained from annual cycles during a 3 year time series (2004, 2005, and 2006) at a fixed shelf station and from spring-summer surveys during the same years. C-specific growth rates (g) varied extensively among species and under variable environmental conditions; however, g values were not correlated to either near surface temperature or copepod size. Copepod biomass (CB) and CP were higher within the coastal upwelling <span class="hlt">zone</span> (<50 km) and both decreased substantially from 2004 to 2006. Annual CP ranged between 24 and 52 g C m-2 year-1 with a~mean annual P/B ratio of 2.7. We estimated that CP could consume up to 60% of the annual primary production (PP) in the upwelling <span class="hlt">zone</span> but most of the time is around 8%. Interannual changes in CB and CP values were associated with changes in the copepod community structure, the dominance of large-sized forms replaced by small-sized species from 2004 to 2006. This change was accompanied by more persistent and time extended upwelling during the same seasonal period. Extended upwelling may have caused large losses of CB from the upwelling <span class="hlt">zone</span> due to an increase in offshore advection of coastal plankton. On a larger scale, these results suggest that climate-related impacts of increasing wind-driven upwelling in coastal upwelling systems may generate a negative trend in zooplankton biomass.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/53895','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/53895"><span>Areas of residential development in the <span class="hlt">southern</span> Appalachian Mountains are characterized by low riparian <span class="hlt">zone</span> nitrogen cycling and no increase in soil greenhouse gas emissions</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Peter Baas; Jennifer D. Knoepp; Daniel Markewitz; Jacqueline E. Mohan</p> <p>2017-01-01</p> <p>The critical role streamside riparian <span class="hlt">zones</span> play in mitigating the movement of nitrogen (N) and other elements from terrestrial to aquatic ecosystems could be threatened by residential development in the <span class="hlt">southern</span> Appalachian Mountains. Many studies have investigated the influence of agriculture on N loading to streams but less is known about the impacts of residential...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.T31B1305S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.T31B1305S"><span>Normal Faulting at the Western Margin of the Altiplano Plateau, <span class="hlt">Southern</span> Peru</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schildgen, T. F.; Hodges, K. V.; Whipple, K. X.; Perignon, M.; Smith, T. M.</p> <p>2004-12-01</p> <p>Although the western margin of the Altiplano Plateau is commonly used to illustrate the marked differences in the evolution of a mountain range with strong latitudinal and longitudinal precipitation gradients, the nature of tectonism in this semi-arid region is poorly understood and much debated. The western margin of the Altiplano in <span class="hlt">southern</span> Peru and northern <span class="hlt">Chile</span> marks an abrupt transition from the forearc region of the Andes to the high topography of the Cordillera Occidental. This transition has been interpreted by most workers as a monocline, with modifications due to thrust faulting, normal faulting, and gravity slides. Based on recent fieldwork and satellite image analysis, we suggest that, at least in the semi-arid climate of <span class="hlt">southern</span> Peru, this transition has been the locus of significant high-angle normal faulting related to the block uplift of the Cordillera Occidental. We have focused our initial work in the vicinity of 15\\deg S latitude, 71\\deg W longitude, where the range front crosses Colca Canyon, a major antecedent drainage northwest of Arequipa. In that area, Oligocene to Miocene sediments of the Moquegua Formation, which were eroded from uplifted terrain to the northeast, presently dip to the northeast at angles between 2 and 10º. Field observations of a normal fault contact between the Moquegua sedimentary rocks and Jurassic basement rocks, as well as 15-m resolution 3-D images generated from ASTER satellite imagery, show that the Moquegua units are down-dropped to the west across a steeply SW-dipping normal fault of regional significance. Morphology of the range front throughout <span class="hlt">southern</span> Peru suggests that normal faulting along the range front has characterized the recent tectonic history of the region. We present geochronological data to constrain the timing of movement both directly from the fault <span class="hlt">zone</span> as well as indirectly from canyon incision that likely responded to fault movement.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25530639','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25530639"><span>The Influence of Weather Anomalies on Mercury Cycling in the Marine Coastal <span class="hlt">Zone</span> of the <span class="hlt">Southern</span> Baltic-Future Perspective.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bełdowska, Magdalena</p> <p>2015-01-01</p> <p>Despite the decreased emission loads of mercury, historical deposits of this metal in various compartments of the environment may become an additional diffuse source in the future. Global climate change manifests itself in the temperate <span class="hlt">zone</span> in several ways: warmer winters, shorter icing periods, increased precipitation and heightened frequency of extreme events such as strong gales and floods, all of which cause disturbances in the rate and direction of mercury biogeochemical cycling. The present study was conducted at two sites, Oslonino and Gdynia Orlowo (both in the coastal <span class="hlt">zone</span> of the Gulf of Gdansk), from which samples were collected once a month between January 2012 and December 2012. In the <span class="hlt">Southern</span> Baltic region, climate changes can certainly enhance coast to basin fluxes of mercury and the transfer of bioavailable forms of this metal to the food web. They may also, in the future, contribute to uncontrollable increases of mercury in the seawater.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA516338','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA516338"><span><span class="hlt">Chile</span> Earthquake: U.S. and International Response</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2010-03-11</p> <p>5 United Nations Office for the Coordination of Humanitarian Affairs, “<span class="hlt">Chile</span> Earthquake: Situation Report #2,” March 1, 2010; Gobierno de <span class="hlt">Chile</span>...U.S. Department of State, March 2, 2010. 6 “Bachelet decreta primer Estado de Catástrofe desde terremoto de 1985,” El Mercurio (<span class="hlt">Chile</span>), March 1...2010; “Amplían toque de queda en zonas más afectadas por terremoto en <span class="hlt">Chile</span>,” Agence France Presse, March 1, 2010; “160 detained, one killed during</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PEPI..132..157L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PEPI..132..157L"><span>Slab-pull and slab-push earthquakes in the Mexican, Chilean and Peruvian subduction <span class="hlt">zones</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lemoine, A.; Madariaga, R.; Campos, J.</p> <p>2002-09-01</p> <p>We studied intermediate depth earthquakes in the <span class="hlt">Chile</span>, Peru and Mexican subduction <span class="hlt">zones</span>, paying special attention to slab-push (down-dip compression) and slab-pull (down-dip extension) mechanisms. Although, slab-push events are relatively rare in comparison with slab-pull earthquakes, quite a few have occurred recently. In Peru, a couple slab-push events occurred in 1991 and one slab-pull together with several slab-push events occurred in 1970 near Chimbote. In Mexico, several slab-push and slab-pull events occurred near Zihuatanejo below the fault <span class="hlt">zone</span> of the 1985 Michoacan event. In central <span class="hlt">Chile</span>, a large M=7.1 slab-push event occurred in October 1997 that followed a series of four shallow Mw>6 thrust earthquakes on the plate interface. We used teleseismic body waveform inversion of a number of Mw>5.9 slab-push and slab-pull earthquakes in order to obtain accurate mechanisms, depths and source time functions. We used a master event method in order to get relative locations. We discussed the occurrence of the relatively rare slab-push events in the three subduction <span class="hlt">zones</span>. Were they due to the geometry of the subduction that produces flexure inside the downgoing slab, or were they produced by stress transfer during the earthquake cycle? Stress transfer can not explain the occurence of several compressional and extensional intraplate intermediate depth earthquakes in central <span class="hlt">Chile</span>, central Mexico and central Peru. It seemed that the heterogeneity of the stress field produced by complex slab geometry has an important influence on intraplate intermediate depth earthquakes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29626330','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29626330"><span>Distribution of greenhouse gases in hyper-arid and arid areas of northern <span class="hlt">Chile</span> and the contribution of the high altitude wetland microbiome (Salar de Huasco, <span class="hlt">Chile</span>).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Molina, Verónica; Eissler, Yoanna; Cornejo, Marcela; Galand, Pierre E; Dorador, Cristina; Hengst, Martha; Fernandez, Camila; Francois, Jean Pierre</p> <p>2018-04-06</p> <p>Northern <span class="hlt">Chile</span> harbors different bioclimatic <span class="hlt">zones</span> including hyper-arid and arid ecosystems and hotspots of microbial life, such as high altitude wetlands, which may contribute differentially to greenhouse gases (GHG) such as carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O). In this study, we explored ground level GHG distribution and the potential role of a wetland situated at 3800 m.a.s.l, and characterized by high solar radiation < 1600 W m -2 , extreme temperature ranges (-12 to 24 °C) and wind stress (< 17 m s -1 ). The water source of the wetland is mainly groundwater springs, which generates streams and ponds surrounded by peatlands. These sites support a rich microbial aquatic life including diverse bacteria and archaea communities, which transiently form more complex structures, such as microbial mats. In this study, GHG were measured in the water and above ground level air at the wetland site and along an elevation gradient in different bioclimatic areas from arid to hyper-arid <span class="hlt">zones</span>. The microbiome from the water and sediments was described by high-throughput sequencing 16S rRNA and rDNA genes. The results indicate that GHG at ground level were variable along the elevation gradient potentially associated with different bioclimatic <span class="hlt">zones</span>, reaching high values at the high Andean steppe and variable but lower values in the Atacama Desert and at the wetland. The water areas of the wetland presented high concentrations of CH 4 and CO 2 , particularly at the spring areas and in air bubbles below microbial mats. The microbial community was rich (> 40 phyla), including archaea and bacteria potentially active in the different matrices studied (water, sediments and mats). Functional microbial groups associated with GHG recycling were detected at low frequency, i.e., < 2.5% of total sequences. Our results indicate that hyper-arid and arid areas of northern <span class="hlt">Chile</span> are sites of GHG exchange associated with various bioclimatic <span class="hlt">zones</span> and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013Tecto..32..516G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013Tecto..32..516G"><span>Thermochronometrically constrained anatomy and evolution of a Miocene extensional accommodation <span class="hlt">zone</span> and tilt domain boundary: The <span class="hlt">southern</span> Wassuk Range, Nevada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gorynski, Kyle E.; Stockli, Daniel F.; Douglas Walker, J.</p> <p>2013-06-01</p> <p>(AHe) and Zircon (ZHe) (U-Th)/He thermochronometric data from the <span class="hlt">southern</span> Wassuk Range (WR) coupled with 40Ar/39Ar age data from the overlying tilted Tertiary section are used to constrain the thermal evolution of an extensional accommodation <span class="hlt">zone</span> and tilt-domain boundary. AHe and ZHe data record two episodes of rapid cooling related to the tectonic exhumation of the WR fault block beginning at ~15 and ~4 Ma. Extension was accommodated through fault-block rotation and variably tilted the <span class="hlt">southern</span> WR to the west from ~60°-70° in the central WR to ~15°-35° in the southernmost WR and Pine Grove Hills, and minimal tilting in the Anchorite Hills and along the Mina Deflection to the south. Middle Miocene geothermal gradient estimates record heating immediately prior to large-magnitude extension that was likely coeval with the extrusion of the Lincoln Flat andesite at ~14.8 Ma. Geothermal gradients increase from ~19° ± 4°C/km to ≥ 65° ± 20°C/km toward the Mina Deflection, suggesting that it was the focus of Middle Miocene arc magmatism in the upper crust. The decreasing thickness of tilt blocks toward the south resulted from a shallowing brittle/ductile transition <span class="hlt">zone</span>. Postmagmatic Middle Miocene extension and fault-block advection were focused in the northern and central WR and coincidentally moderated the large lateral thermal gradient within the uppermost crust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.T53D2616P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.T53D2616P"><span>Evidences of a Lithospheric Fault <span class="hlt">Zone</span> in the Sicily Channel Continental Rift (<span class="hlt">Southern</span> Italy) from Instrumental Seismicity Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parisi, L.; Calo, M.</p> <p>2013-12-01</p> <p>The Sicily Channel continental rift is located in the African Plate and is submerged by a shallow sea extending from the northern coast of Africa to the <span class="hlt">southern</span> coast of Sicily (<span class="hlt">southern</span> Italy). The area is affected by an extensional regime since early Pliocene, which thins the continental crust and produces NW-SE oriented Pantelleria, Linosa and Malta grabens. The rift-related volcanic activity is represented by Pantelleria and Linosa Islands and a series of magmatic manifestations roughly NNE-SSW aligned, from Linosa Island to the Nameless Bank, in proximity of the Sicilian coast. Recent rapid magmatic ascents occurred along the strip near to the Sicilian coast in a region named Graham Bank. The NNE-SSW strip has already been recognised as a separation belt between the western sector of the rift (Pantelleria graben) and the eastern one (Linosa and Malta grabens). Seismic profiles suggest the presence of near vertical structures associated with strike slip fault <span class="hlt">zones</span>. Bathymetric data show a 15-20 km wide <span class="hlt">zone</span> characterised by several shallow basins irregularly alternated by topographic highs. However, evidences of a N-S or NNE-SSW orientated faults have not been found. In this work we re-localised the instrumental seismicity recorded between 1981 and 2012 in the Sicily Channel and western Sicily using the Double Difference method (Waldhauser, 2001, 2012) and 3D Vp and Vs models (Calò et al., 2013). The statistical analysis of the relocated seismicity together with the study of seismic energy release distribution allows us to describe the main patterns associated with the active faults in the western Sicily Straits. Here we find that most of the events in the Sicily Channel are highly clustered between 12.5°- 13.5°E and 35.5°-37°N with hypocentral depth between 5-40 km, reaching in some cases 70 km of depth. Seismic events seem to be aligned along a sub-vertical shear <span class="hlt">zone</span> that is long at least 250 km and oriented approximately NNE-SSW. The spatial</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=mapuche&pg=2&id=EJ203627','ERIC'); return false;" href="https://eric.ed.gov/?q=mapuche&pg=2&id=EJ203627"><span>Rule of Repression in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>American Indian Journal, 1979</p> <p>1979-01-01</p> <p>This report on the current condition of the Mapuche Indians of <span class="hlt">Chile</span> is edited from a document on the "Situation of Human Rights in <span class="hlt">Chile</span>" and details the repressive and inhumane treatment of the largest indigenous ethnic minority in the country. (Author/RTS)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004ThApC..77..173C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004ThApC..77..173C"><span>Characterization of potential <span class="hlt">zones</span> of dust generation at eleven stations in the <span class="hlt">southern</span> Sahara</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clark, I.; Assamoi, P.; Bertrand, J.; Giorgi, F.</p> <p></p> <p>Synoptic wind data for multi-decadal periods at eleven stations located in the <span class="hlt">southern</span> Sahara region (Agadez, Atar, Bilma, Dori, Gao, Kayes, Nema, Niamey, Nouadhibou, Ouagadougou and Tessalit) are used to study the monthly dust deflation power over the region. We found that, regardless of the conditions of the soil, the deflation power (or wind efficiency) is not sufficient to generate significant amounts of aerosols south of 15°N. North of this latitude, the deflation power is much larger, with potential <span class="hlt">zones</span> of either very strong deflation (Nouadhibou and Bilma) or severe deflation (Gao, Tessalit, Nema, Atar, Agadez). Stations in the Sahel region such as Gao, Agadez and Tessalit are characterized by a gradual reinforcement of the deflation power between 1970 and 1984 in correspondence of increasing desertification over the region. During this same period, Bilma, a well know region of dust source, experienced a major reduction in deflation power due to shifts in large scale wind patterns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12313739','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12313739"><span>[Determinants of the rural exodus: the importance of place of origin factors, <span class="hlt">Chile</span>, 1965-1970].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Raczynski, D</p> <p>1982-07-01</p> <p>Trends in rural-urban migration in <span class="hlt">Chile</span> during the period 1965-1970 are analyzed, with a focus on the impact of the combination of structural factors and socioeconomic processes in rural areas. Factors of population retention and expulsion are examined in terms of agrarian structure, the process of agrarian reform, urbanization of the countryside, and the availability of basic social services. Rural-urban migration rates in the central and <span class="hlt">southern</span> areas of the country are compared, and migration rates of males and females are examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ACP....17.6477A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ACP....17.6477A"><span>Surface ozone in the <span class="hlt">Southern</span> Hemisphere: 20 years of data from a site with a unique setting in El Tololo, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anet, Julien G.; Steinbacher, Martin; Gallardo, Laura; Velásquez Álvarez, Patricio A.; Emmenegger, Lukas; Buchmann, Brigitte</p> <p>2017-05-01</p> <p>The knowledge of surface ozone mole fractions and their global distribution is of utmost importance due to the impact of ozone on human health and ecosystems and the central role of ozone in controlling the oxidation capacity of the troposphere. The availability of long-term ozone records is far better in the Northern than in the <span class="hlt">Southern</span> Hemisphere, and recent analyses of the seven accessible records in the <span class="hlt">Southern</span> Hemisphere have shown inconclusive trends. Since late 1995, surface ozone is measured in situ at "El Tololo", a high-altitude (2200 m a.s.l.) and pristine station in <span class="hlt">Chile</span> (30° S, 71° W). The dataset has been recently fully quality controlled and reprocessed. This study presents the observed ozone trends and annual cycles and identifies key processes driving these patterns. From 1995 to 2010, an overall positive trend of ˜ 0.7 ppb decade-1 is found. Strongest trends per season are observed in March and April. Highest mole fractions are observed in late spring (October) and show a strong correlation with ozone transported from the stratosphere down into the troposphere, as simulated with a model. Over the 20 years of observations, the springtime ozone maximum has shifted to earlier times in the year, which, again, is strongly correlated with a temporal shift in the occurrence of the maximum of simulated stratospheric ozone transport at the site. We conclude that background ozone at El Tololo is mainly driven by stratospheric intrusions rather than photochemical production from anthropogenic and biogenic precursors. The major footprint of the sampled air masses is located over the Pacific Ocean. Therefore, due to the negligible influence of local processes, the ozone record also allows studying the influence of El Niño and La Niña episodes on background ozone levels in South America. In agreement with previous studies, we find that, during La Niña conditions, ozone mole fractions reach higher levels than during El Niño conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18589572','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18589572"><span>[Differentiated perception of transgenic tomato sauce in the <span class="hlt">southern</span> <span class="hlt">Chile</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schnettler Morales, B; Sepúlveda Bravo, O; Ruiz Fuentes, D; Denegri Coria, M</p> <p>2008-03-01</p> <p>The present study considers the debate generated in developed countries by genetically modified foods, the importance of this variable to consumers in Temuco (Araucanía Region, <span class="hlt">Chile</span>) when purchasing tomato sauce and different market segments were studied through a personal survey administered to 400 people. Using conjoint analysis, it was determined that the presence of genetic modification in food was generally more important than the brand and purchase price. Using cluster analysis, three segments were distinguished, with the most numerous (49.3%) placing the greatest importance on the presence of genetic modification (GM) in food and rejecting the transgenic product. The second group (39.4%) gave the greatest importance to the brand and preferred tomato sauce with genetically modified ingredients. The smallest segment (11.3%) placed the greatest value on price and preferred transgenic tomato sauce. The three segments prefer the national brand, reject the store brand and react positively to lower prices. The segment sensitive to the presence of GM in food comprised mainly those younger than 35 years of age, single and with no children. The absence of GM in food of vegetable origin is desirable for young consumers in the Araucanía Region, but a significant proportion accepts genetic modification in food (50.7%).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JVGR..324...88S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JVGR..324...88S"><span>Physical, chemical and mineralogical evolution of the Tolhuaca geothermal system, <span class="hlt">southern</span> Andes, <span class="hlt">Chile</span>: Insights into the interplay between hydrothermal alteration and brittle deformation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sanchez-Alfaro, Pablo; Reich, Martin; Arancibia, Gloria; Pérez-Flores, Pamela; Cembrano, José; Driesner, Thomas; Lizama, Martin; Rowland, Julie; Morata, Diego; Heinrich, Christoph A.; Tardani, Daniele; Campos, Eduardo</p> <p>2016-09-01</p> <p>In this study, we unravel the physical, chemical and mineralogical evolution of the active Tolhuaca geothermal system in the Andes of <span class="hlt">southern</span> <span class="hlt">Chile</span>. We used temperature measurements in the deep wells and geochemical analyses of borehole fluid samples to constrain present-day fluid conditions. In addition, we reconstructed the paleo-fluid temperatures and chemistry from microthermometry and LA-ICP-MS analysis of fluid inclusions taken from well-constrained parageneses in vein samples retrieved from a 1000 m borehole core. Based on core logging, mineralogical observations and fluid inclusions data we identify four stages (S1-S4) of progressive hydrothermal alteration. An early heating event (S1) was followed by the formation of a clay-rich cap in the upper <span class="hlt">zone</span> (< 670 m) and the development of a propylitic alteration assemblage at greater depth (S2). Boiling, flashing and brecciation occurred later (S3), followed by a final phase of fluid mixing and boiling (S4). The evolution of hydrothermal alteration at Tolhuaca has produced a mineralogical, hydrological and structural vertical segmentation of the system through the development of a low-permeability, low-cohesion clay-rich cap at shallow depth. The quantitative chemical analyses of fluid inclusions and borehole fluids reveal a significant change in chemical conditions during the evolution of Tolhuaca. Whereas borehole (present-day) fluids are rich in Au, B and As, but Cu-poor (B/Na 100.5, As/Na 10- 1.1, Cu/Na 10- 4.2), the paleofluids trapped in fluid inclusions are Cu-rich but poor in B and As (B/Na 10- 1, As/Na 10- 2.5, Cu/Na 10- 2.5 in average). We interpret the fluctuations in fluid chemistry at Tolhuaca as the result of transient supply of metal-rich, magmatically derived fluids where As, Au and Cu are geochemically decoupled. Since these fluctuating physical and chemical conditions at the reservoir produced a mineralogical vertical segmentation of the system that affects the mechanical and hydrological</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2013-06-28/pdf/2013-15549.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2013-06-28/pdf/2013-15549.pdf"><span>78 FR 38922 - Foreign-Trade <span class="hlt">Zone</span> 189-Kent/Ottawa/Muskegon Counties, Michigan; Authorization of Production...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2013-06-28</p> <p>... DEPARTMENT OF COMMERCE Foreign-Trade <span class="hlt">Zones</span> Board [B-19-2013] Foreign-Trade <span class="hlt">Zone</span> 189--Kent/Ottawa/Muskegon Counties, Michigan; Authorization of Production Activity; <span class="hlt">Southern</span> Lithoplate, Inc. (Aluminum Printing Plates); Grand Rapids, Michigan On February 22, 2013, <span class="hlt">Southern</span> Lithoplate, Inc. submitted a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JAESc..56..263K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JAESc..56..263K"><span>Rb-Sr, Sm-Nd, and U-Pb geochronology of the rocks within the Khlong Marui shear <span class="hlt">zone</span>, <span class="hlt">southern</span> Thailand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanjanapayont, Pitsanupong; Klötzli, Urs; Thöni, Martin; Grasemann, Bernhard; Edwards, Michael A.</p> <p>2012-08-01</p> <p>In <span class="hlt">southern</span> Thailand, the Khlong Marui shear <span class="hlt">zone</span> is dominated by a NNE-SSW striking high topographic lozenge shaped area of ca. 40 km long and 6 km wide between the Khlong Marui Fault and the Bang Kram Fault. The geology within this strike-slip <span class="hlt">zone</span> consists of strongly deformed layers of mylonitic meta-sedimentary rocks associated with orthogneisses, mylonitic granites, and pegmatitic veins with a steeply dipping foliation. The strike-slip deformation is characterized by dextral ductile deformation under amphibolite facies and low to medium greenschist facies. In situ U-Pb ages of inherited zircon cores from all zircons in the Khlong Marui shear <span class="hlt">zone</span> indicate that they have the same material from the Archean. Late Triassic to Late Cretaceous ages obtained for zircon outer cores of the mylonitic granite are probably related to a period of magmatic activity that was significantly influenced by the West Burma and Shan-Thai collision and the subduction along the Sunda Trench. The early dextral ductile deformation phase of the Khlong Marui shear <span class="hlt">zone</span> in the Early Eocene suggested by U-Pb ages of zircon rims, and the later dextral transpressional deformation in the Late Eocene indicated by mica Rb-Sr ages. Rb-Sr, Sm-Nd, and U-Pb dating correlation implies that the major exhumation period of the ductile lens was in the Eocene. This period was tectonically influenced in the SE Asia region by the early India-Asia collision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JPhCS.979a2051S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JPhCS.979a2051S"><span>Response of Gravity, Magnetic, and Geoelectrical Resistivity Methods on Ngeni <span class="hlt">Southern</span> Blitar Mineralization <span class="hlt">Zone</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sunaryo</p> <p>2018-03-01</p> <p>The research with entitle response of gravity, magnetic, and geoelectrical resistivity methods on Ngeni <span class="hlt">Southern</span> Blitar mineralization <span class="hlt">zone</span> has been done. This study aims to find the response of several geophysical methods of gravity, magnetic, and geoelectrical resistivity in an integrated manner. Gravity data acquisition was acquired 224 data which covers the whole region of Blitar district by using Gravity Meter La Coste & Romberg Model “G”, and magnetic data acquisition were acquired 195 data which covers the <span class="hlt">southern</span> Blitar district only by using Proton Precession Magnetometer G-856. Meanwhile geoelectrical resistivity data only done in Ngeni village which is the location of phyropilite mining with the composition content of Fe, Si, Ca, S, Cu, and Mn by using ABEM Terrameter SAS 300C. Gravity data processing was performed to obtain the Bouguer anomaly value, which included unit conversion, tidal correction, drift correction, correction of tie point, base station correction, free air correction, and Bouguer correction. Magnetic data processing has been done by some corrections i.e daily, drift, and IGRF(International Geomagnetic Refference Field) to obtain the total magnetic anomaly. From gravity data processing has been obtained the simple Bouguer anomaly value in range from -10mGal until 115mGal. From this data processing has been obtained the total magnetic anomaly value in range from -650nT until 800nT. Meanwhile from geoelectrical resistivity 3.03Ωm until 11249.91 Ωm. There is a correlation between gravity anomaly, magnetic anomaly, and geoelectrical resistivity anomaly that are associated with deep anomaly, middle anomaly, and shallow anomaly.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JAESc..42..176C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JAESc..42..176C"><span>Structural anatomy of a dismembered ophiolite suite from Gondwana: The Manamedu complex, Cauvery suture <span class="hlt">zone</span>, <span class="hlt">southern</span> India</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chetty, T. R. K.; Yellappa, T.; Nagesh, P.; Mohanty, D. P.; Venkatasivappa, V.; Santosh, M.; Tsunogae, T.</p> <p>2011-08-01</p> <p>Detailed geological and structural mapping of the Manamedu ophiolite complex (MOC), from the south-eastern part of the Cauvery suture <span class="hlt">zone</span> (CSZ) within the Gondwana collisional suture in <span class="hlt">southern</span> India reveals the anatomy of a dismembered ophiolite succession comprising pyroxenite actinolite-hornblendite, hornblendite, gabbro-norite, gabbro, anorthosite, amphibolite, plagiogranite, mafic dykes, and associated pelagic sediments such as chert-magnetite bands and carbonate horizons. The magmatic foliation trajectory map shows inward dipping foliations and a variety of fold structures. Structural cross-sections of the MOC reveal gentle inward dips with repetition and omission of different lithologies often marked by curvilinear hinge lines. The succession displays imbricate thrust sheets and slices of dismembered ophiolite suites distributed along several localities within the CSZ. The MOC can be interpreted as a deformed large duplex structure associated with south-verging back thrust system, consistent with crustal-scale 'flower structure'. The nature and distribution of ophiolitic rocks in the CSZ suggest supra-subduction <span class="hlt">zone</span> setting associated with the lithospheric subduction of the Neoproterozoic Mozambique Ocean, followed by collision and obduction during the final stage of amalgamation of the Gondwana supercontinent in the end Precambrian.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1987EM%26P...38..183S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1987EM%26P...38..183S"><span>Geology of the <span class="hlt">Southern</span> Ishtar Terra/Guinevere and Sedna Planitae region on Venus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stofan, E. R.; Head, J. W.; Campbell, D. B.</p> <p>1987-06-01</p> <p>High-resolution high-incidence-angle Arecibo images and Pioneer-Venus data of <span class="hlt">Southern</span> Ishtar Terra and the flanking plains of Guinevere and Sena on Venus are analyzed. The low predominantly volcanic plains of Guinevere and Sedna Planitae are the oldest of the mapped terrains. The complex tectonic deformation in the <span class="hlt">Southern</span> Ishtar Transition <span class="hlt">Zone</span> postdates much of the low plains, and delineates the steep-sloped flanks of Ishtar Terra. Lakshmi Planum is found to have a distinctive volcanic style, and to postdate the <span class="hlt">Southern</span> Ishtar Transition <span class="hlt">Zone</span>, at least in part. Data show relatively recent plains-style volcanism to have occurred locally in Sedna Planitae, and to embay the <span class="hlt">Southern</span> Istar Transition <span class="hlt">Zone</span>. Arecibo data show additional coronae in the lowlands, suggesting that corona formation may be a more widespread process than indicated by Venera 15/16 images.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27716089','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27716089"><span>Absence of convincing evidence of Coxiella burnetii infection in <span class="hlt">Chile</span>: a cross-sectional serosurvey among healthy adults in four different regions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Weitzel, Thomas; López, Javier; Acosta-Jamett, Gerardo; Edouard, Sophie; Parola, Philippe; Abarca, Katia</p> <p>2016-10-06</p> <p>Coxiella burnetii is an important zoonotic pathogen of global distribution. Still, in most parts of South America including <span class="hlt">Chile</span>, systematic epidemiological data are lacking. The presented study aims to determine the seroprevalence of Coxiella burnetii antibodies in healthy adults of four different regions in <span class="hlt">Chile</span>. A cross-sectional study was performed, which included healthy adults living in rural and urban areas of four cities located in different regions in northern, central, and <span class="hlt">southern</span> <span class="hlt">Chile</span>. In urban sectors, households were chosen by double stratified random sampling, while in rural areas convenience sampling was performed. Serum specimens were taken and screened for the presence of IgG antibodies against C. burnetii phase II antigen using a commercial ELISA kit. Positive and indeterminate results were confirmed by a reference laboratory using indirect immunofluorescence assay (IFA). A total of 1112 individuals were included. Of those, 8 were positive by ELISA, but only one sample was confirmed using IFA. Statistical analysis for population freedom from disease revealed a high probability that C. burnetii was absent in our study population. Our work provides the first epidemiological data on human Q fever in <span class="hlt">Chile</span> indicating either a very low endemicity or the absence of this pathogen in the studied areas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JSG....27..871S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JSG....27..871S"><span>Geometry and kinematics of adhesive wear in brittle strike-slip fault <span class="hlt">zones</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Swanson, Mark T.</p> <p>2005-05-01</p> <p>Detailed outcrop surface mapping in Late Paleozoic cataclastic strike-slip faults of coastal Maine shows that asymmetric sidewall ripouts, 0.1-200 m in length, are a significant component of many mapped faults and an important wall rock deformation mechanism during faulting. The geometry of these structures ranges from simple lenses to elongate slabs cut out of the sidewalls of strike-slip faults by a lateral jump of the active <span class="hlt">zone</span> of slip during adhesion along a section of the main fault. The new irregular trace of the active fault after this jump creates an indenting asperity that is forced to plow through the adjoining wall rock during continued adhesion or be cut off by renewed motion along the main section of the fault. Ripout translation during adhesion sets up the structural asymmetry with trailing extensional and leading contractional ends to the ripout block. The inactive section of the main fault trace at the trailing end can develop a 'sag' or 'half-graben' type geometry due to block movement along the scallop-shaped connecting ramp to the flanking ripout fault. Leading contractional ramps can develop 'thrust' type imbrication and forces the 'humpback' geometry to the ripout slab due to distortion of the inactive main fault surface by ripout translation. Similar asymmetric ripout geometries are recognized in many other major crustal scale strike-slip fault <span class="hlt">zones</span> worldwide. Ripout structures in the 5-500 km length range can be found on the Atacama fault system of northern <span class="hlt">Chile</span>, the Qujiang and Xiaojiang fault <span class="hlt">zones</span> in western China, the Yalakom-Hozameen fault <span class="hlt">zone</span> in British Columbia and the San Andreas fault system in <span class="hlt">southern</span> California. For active crustal-scale faults the surface expression of ripout translation includes a coupled system of extensional trailing ramps as normal oblique-slip faults with pull-apart basin sedimentation and contractional leading ramps as oblique thrust or high angle reverse faults with associated uplift and erosion. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.174.1845K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.174.1845K"><span>Testing an Earthquake Prediction Algorithm: The 2016 New Zealand and <span class="hlt">Chile</span> Earthquakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kossobokov, Vladimir G.</p> <p>2017-05-01</p> <p>The 13 November 2016, M7.8, 54 km NNE of Amberley, New Zealand and the 25 December 2016, M7.6, 42 km SW of Puerto Quellon, <span class="hlt">Chile</span> earthquakes happened outside the area of the on-going real-time global testing of the intermediate-term middle-range earthquake prediction algorithm M8, accepted in 1992 for the M7.5+ range. Naturally, over the past two decades, the level of registration of earthquakes worldwide has grown significantly and by now is sufficient for diagnosis of times of increased probability (TIPs) by the M8 algorithm on the entire territory of New Zealand and <span class="hlt">Southern</span> <span class="hlt">Chile</span> as far as below 40°S. The mid-2016 update of the M8 predictions determines TIPs in the additional circles of investigation (CIs) where the two earthquakes have happened. Thus, after 50 semiannual updates in the real-time prediction mode, we (1) confirm statistically approved high confidence of the M8-MSc predictions and (2) conclude a possibility of expanding the territory of the Global Test of the algorithms M8 and MSc in an apparently necessary revision of the 1992 settings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70176038','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70176038"><span>The Eastern California Shear <span class="hlt">Zone</span> as the northward extension of the <span class="hlt">southern</span> San Andreas Fault</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Thatcher, Wayne R.; Savage, James C.; Simpson, Robert W.</p> <p>2016-01-01</p> <p>Cluster analysis offers an agnostic way to organize and explore features of the current GPS velocity field without reference to geologic information or physical models using information only contained in the velocity field itself. We have used cluster analysis of the <span class="hlt">Southern</span> California Global Positioning System (GPS) velocity field to determine the partitioning of Pacific-North America relative motion onto major regional faults. Our results indicate the large-scale kinematics of the region is best described with two boundaries of high velocity gradient, one centered on the Coachella section of the San Andreas Fault and the Eastern California Shear <span class="hlt">Zone</span> and the other defined by the San Jacinto Fault south of Cajon Pass and the San Andreas Fault farther north. The ~120 km long strand of the San Andreas between Cajon Pass and Coachella Valley (often termed the San Bernardino and San Gorgonio sections) is thus currently of secondary importance and carries lesser amounts of slip over most or all of its length. We show these first order results are present in maps of the smoothed GPS velocity field itself. They are also generally consistent with currently available, loosely bounded geologic and geodetic fault slip rate estimates that alone do not provide useful constraints on the large-scale partitioning we show here. Our analysis does not preclude the existence of smaller blocks and more block boundaries in <span class="hlt">Southern</span> California. However, attempts to identify smaller blocks along and adjacent to the San Gorgonio section were not successful.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRB..121.2904T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRB..121.2904T"><span>The Eastern California Shear <span class="hlt">Zone</span> as the northward extension of the <span class="hlt">southern</span> San Andreas Fault</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thatcher, W.; Savage, J. C.; Simpson, R. W.</p> <p>2016-04-01</p> <p>Cluster analysis offers an agnostic way to organize and explore features of the current GPS velocity field without reference to geologic information or physical models using information only contained in the velocity field itself. We have used cluster analysis of the <span class="hlt">Southern</span> California Global Positioning System (GPS) velocity field to determine the partitioning of Pacific-North America relative motion onto major regional faults. Our results indicate the large-scale kinematics of the region is best described with two boundaries of high velocity gradient, one centered on the Coachella section of the San Andreas Fault and the Eastern California Shear <span class="hlt">Zone</span> and the other defined by the San Jacinto Fault south of Cajon Pass and the San Andreas Fault farther north. The ~120 km long strand of the San Andreas between Cajon Pass and Coachella Valley (often termed the San Bernardino and San Gorgonio sections) is thus currently of secondary importance and carries lesser amounts of slip over most or all of its length. We show these first order results are present in maps of the smoothed GPS velocity field itself. They are also generally consistent with currently available, loosely bounded geologic and geodetic fault slip rate estimates that alone do not provide useful constraints on the large-scale partitioning we show here. Our analysis does not preclude the existence of smaller blocks and more block boundaries in <span class="hlt">Southern</span> California. However, attempts to identify smaller blocks along and adjacent to the San Gorgonio section were not successful.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001EP%26S...53..307R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001EP%26S...53..307R"><span>Stress on the seismogenic and deep creep plate interface during the earthquake cycle in subduction <span class="hlt">zones</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruff, Larry J.</p> <p>2001-04-01</p> <p>The deep creep plate interface extends from the down-dip edge of the seismogenic <span class="hlt">zone</span> down to the base of the overlying lithosphere in subduction <span class="hlt">zones</span>. Seismogenic/deep creep <span class="hlt">zone</span> interaction during the earthquake cycle produces spatial and temporal variations in strains within the surrounding elastic material. Strain observations in the Nankai subduction <span class="hlt">zone</span> show distinct deformation styles in the co-seismic, post-seismic, and inter-seismic phases associated with the 1946 great earthquake. The most widely used kinematic model to match geodetic observations has been a 2-D Savage-type model where a plate interface is placed in an elastic half-space and co-seismic slip occurs in the upper seismogenic portion of the interface, while inter-seismic deformation is modeled by a locked seismogenic <span class="hlt">zone</span> and a constant slip velocity across the deep creep interface. Here, I use the simplest possible 2-D mechanical model with just two blocks to study the stress interaction between the seismogenic and deep creep <span class="hlt">zones</span>. The seismogenic <span class="hlt">zone</span> behaves as a stick-slip interface where co-seismic slip or stress drop constrain the model. A linear constitutive law for the deep creep <span class="hlt">zone</span> connects the shear stress (σ) to the slip velocity across the plate interface (s') with the material property of interface viscosity (ζ ) as: σ = ζ s'. The analytic solution for the steady-state two-block model produces simple formulas that connect some spatially-averaged geodetic observations to model quantities. Aside from the basic subduction <span class="hlt">zone</span> geometry, the key observed parameter is τ, the characteristic time of the rapid post-seismic slip in the deep creep interface. Observations of τ range from about 5 years (Nankai and Alaska) to 15 years (<span class="hlt">Chile</span>). The simple model uses these values for τ to produce estimates for ζ that range from 8.4 × 1013 Pa/m/s (in Nankai) to 6.5 × 1014 Pa/m/s (in <span class="hlt">Chile</span>). Then, the model predicts that the shear stress acting on deep creep interface averaged over</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5780666','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5780666"><span>Epidemiologic and virologic assessment of the 2009 influenza A (H1N1) pandemic on selected temperate countries in the <span class="hlt">Southern</span> Hemisphere: Argentina, Australia, <span class="hlt">Chile</span>, New Zealand and South Africa</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Van Kerkhove, Maria D.; Mounts, Anthony W.; Mall, Sabine; Vandemaele, Katelijn A.H.; Chamberland, Mary; dos Santos, Thais; Fitzner, Julia; Widdowson, Marc‐Alain; Michalove, Jennifer; Bresee, Joseph; Olsen, Sonja J.; Quick, Linda; Baumeister, Elsa; Carlino, Luis O.; Savy, Vilma; Uez, Osvaldo; Owen, Rhonda; Ghani, Fatima; Paterson, Bev; Forde, Andrea; Fasce, Rodrigo; Torres, Graciela; Andrade, Winston; Bustos, Patricia; Mora, Judith; Gonzalez, Claudia; Olea, Andrea; Sotomayor, Viviana; Najera De Ferrari, Manuel; Burgos, Alejandra; Hunt, Darren; Huang, Q. Sue; Jennings, Lance C.; Macfarlane, Malcolm; Lopez, Liza D.; McArthur, Colin; Cohen, Cheryl; Archer, Brett; Blumberg, Lucille; Cengimbo, Ayanda; Makunga, Chuma; McAnerney, Jo; Msimang, Veerle; Naidoo, Dhamari; Puren, Adrian; Schoub, Barry; Thomas, Juno; Venter, Marietjie</p> <p>2011-01-01</p> <p>Please cite this paper as: Van Kerkhove et al. (2011) Epidemiologic and virologic assessment of the 2009 influenza A (H1N1) pandemic on selected temperate countries in the <span class="hlt">Southern</span> Hemisphere: Argentina, Australia, <span class="hlt">Chile</span>, New Zealand and South Africa. Influenza and Other Respiratory Viruses 5(6), e487–e498. Introduction and Setting  Our analysis compares the most comprehensive epidemiologic and virologic surveillance data compiled to date for laboratory‐confirmed H1N1pdm patients between 1 April 2009 ‐ 31 January 2010 from five temperate countries in the <span class="hlt">Southern</span> Hemisphere–Argentina, Australia, <span class="hlt">Chile</span>, New Zealand, and South Africa. Objective  We evaluate transmission dynamics, indicators of severity, and describe the co‐circulation of H1N1pdm with seasonal influenza viruses. Results  In the five countries, H1N1pdm became the predominant influenza strain within weeks of initial detection. South Africa was unique, first experiencing a seasonal H3N2 wave, followed by a distinct H1N1pdm wave. Compared with the 2007 and 2008 influenza seasons, the peak of influenza‐like illness (ILI) activity in four of the five countries was 3‐6 times higher with peak ILI consultation rates ranging from 35/1,000 consultations/week in Australia to 275/100,000 population/week in New Zealand. Transmission was similar in all countries with the reproductive rate ranging from 1.2–1.6. The median age of patients in all countries increased with increasing severity of disease, 4–14% of all hospitalized cases required critical care, and 26–68% of fatal patients were reported to have ≥1 chronic medical condition. Compared with seasonal influenza, there was a notable downward shift in age among severe cases with the highest population‐based hospitalization rates among children <5 years old. National population‐based mortality rates ranged from 0.8–1.5/100,000. Conclusions  The difficulty experienced in tracking the progress of the pandemic globally, estimating</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.V13B2351A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.V13B2351A"><span>Use of high-resolution satellite images for characterization of geothermal reservoirs in the Tarapaca Region, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arellano-Baeza, A. A.; Montenegro A., C.</p> <p>2010-12-01</p> <p>The use of renewable and clean sources of energy is becoming crucial for sustainable development of all countries, including <span class="hlt">Chile</span>. Chilean Government plays special attention to the exploration and exploitation of geothermal energy, total electrical power capacity of which could reach 16.000 MW. In <span class="hlt">Chile</span> the main geothermal fields are located in the Central Andean Volcanic Chain in the North, between the Central valley and the border with Argentina in the center, and in the fault system Liquiñe-Ofqui in the South of the country. High resolution images from the Lansat satellite have been used to characterize the geothermal field in the region of the Puchuldiza geysers, Colchane, Region of Tarapaca, North of <span class="hlt">Chile</span>, located at the altitude of 4000 m. Structure of lineaments associated to the geothermal field have been extracted from the images using the lineament detection technique developed by authors. These structures have been compared with the distribution of main geological structures obtained in the field. It was found that the lineament analysis is a power tool for the detection of faults and joint <span class="hlt">zones</span> associated to the geothermal fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/231058-breaker-zone-aerosol-dynamics-southern-baltic-sea','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/231058-breaker-zone-aerosol-dynamics-southern-baltic-sea"><span>Breaker <span class="hlt">zone</span> aerosol dynamics in the <span class="hlt">southern</span> Baltic Sea</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zielinski, T.; Zielinski, A.</p> <p></p> <p>This paper presents the results of lidar based investigations of aerosol concentrations and their size distributions over the breaker <span class="hlt">zones</span>. The measurements were carried out under various weather conditions over breaker <span class="hlt">zones</span> of the Gulf of Gdansk (1992) and from a station on the open Baltic Sea (International Experiment BAEX in 1993).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GPC...146..152U','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GPC...146..152U"><span>Wildfires in <span class="hlt">Chile</span>: A review</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Úbeda, Xavier; Sarricolea, Pablo</p> <p>2016-11-01</p> <p>This paper reviews the literature examining the wildfire phenomenon in <span class="hlt">Chile</span>. Since ancient times, <span class="hlt">Chile</span>'s wildfires have shaped the country's landscape, but today, as in many other parts of the world, the fire regime - pattern, frequency and intensity - has grown at an alarming rate. In 2014, > 8000 fires were responsible for burning c. 130,000 ha, making it the worst year in <span class="hlt">Chile</span>'s recent history. The reasons for this increase appear to be the increment in the area planted with flammable species; the rejection of these landscape modifications on the part of local communities that target these plantations in arson attacks; and, the adoption of intensive forest management practices resulting in the accumulation of a high fuel load. These trends have left many native species in a precarious situation and forest plantation companies under considerable financial pressure. An additional problem is posed by fires at the wildland urban interface (WUI), threatening those inhabitants that live in <span class="hlt">Chile</span>'s most heavily populated cities. The prevalence of natural fires in <span class="hlt">Chile</span>; the relationship between certain plant species and fire in terms of seed germination strategies and plant adaptation; the relationship between fire and invasive species; and, the need for fire prevention systems and territorial plans that include fire risk assessments are some of the key aspects discussed in this article. Several of the questions raised will require further research, including just how fire-dependent the ecosystems in <span class="hlt">Chile</span> are, how the forest at the WUI can be better managed to prevent human and material damage, and how best to address the social controversy that pits the Mapuche population against the timber companies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JSAES..42...91A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JSAES..42...91A"><span>Middle Miocene vertebrates from the Amazonian Madre de Dios Subandean <span class="hlt">Zone</span>, Perú</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Antoine, Pierre-Olivier; Roddaz, Martin; Brichau, Stéphanie; Tejada-Lara, Julia; Salas-Gismondi, Rodolfo; Altamirano, Ali; Louterbach, Mélanie; Lambs, Luc; Otto, Thierry; Brusset, Stéphane</p> <p>2013-03-01</p> <p>A new middle Miocene vertebrate fauna from Peruvian Amazonia is described. It yields the marsupials Sipalocyon sp. (Hathliacynidae) and Marmosa (Micoureus) cf. laventica (Didelphidae), as well as an unidentified glyptodontine xenarthran and the rodents Guiomys sp. (Caviidae), “Scleromys” sp., cf. quadrangulatus-schurmanni-colombianus (Dinomyidae), an unidentified acaremyid, and cf. Microsteiromys sp. (Erethizontidae). Apatite Fission Track provides a detrital age (17.1 ± 2.4 Ma) for the locality, slightly older than its inferred biochronological age (Colloncuran-early Laventan South American Land Mammal Ages: ˜15.6-13.0 Ma). Put together, both the mammalian assemblage and lithology of the fossil-bearing level point to a mixture of tropical rainforest environment and more open habitats under a monsoonal-like tropical climate. The fully fluvial origin of the concerned sedimentary sequence suggests that the Amazonian Madre de Dios Subandean <span class="hlt">Zone</span> was not part of the Pebas mega-wetland System by middle Miocene times. This new assemblage seems to reveal a previously undocumented “spatiotemporal transition” between the late early Miocene assemblages from high latitudes (Patagonia and <span class="hlt">Southern</span> <span class="hlt">Chile</span>) and the late middle Miocene faunas of low latitudes (Colombia, Perú, Venezuela, and ?Brazil).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3929388','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3929388"><span>Phylogeographic Structure in Benthic Marine Invertebrates of the Southeast Pacific Coast of <span class="hlt">Chile</span> with Differing Dispersal Potential</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Haye, Pilar A.; Segovia, Nicolás I.; Muñoz-Herrera, Natalia C.; Gálvez, Francisca E.; Martínez, Andrea; Meynard, Andrés; Pardo-Gandarillas, María C.; Poulin, Elie; Faugeron, Sylvain</p> <p>2014-01-01</p> <p>The role of dispersal potential on phylogeographic structure, evidenced by the degree of genetic structure and the presence of coincident genetic and biogeographic breaks, was evaluated in a macrogeographic comparative approach along the north-central coast of <span class="hlt">Chile</span>, across the biogeographic transition <span class="hlt">zone</span> at 30°S. Using 2,217 partial sequences of the mitochondrial Cytochrome Oxidase I gene of eight benthic invertebrate species along ca. 2,600 km of coast, we contrasted dispersal potential with genetic structure and determined the concordance between genetic divergence between biogeographic regions and the biogeographic transition <span class="hlt">zone</span> at 30°S. Genetic diversity and differentiation highly differed between species with high and low dispersal potential. Dispersal potential, sometimes together with biogeographic region, was the factor that best explained the genetic structure of the eight species. The three low dispersal species, and one species assigned to the high dispersal category, had a phylogeographic discontinuity coincident with the biogeographic transition <span class="hlt">zone</span> at 30°S. Furthermore, coalescent analyses based on the isolation-with-migration model validate that the split between biogeographic regions north and south of 30°S has a historic origin. The signatures of the historic break in high dispersers is parsimoniously explained by the homogenizing effects of gene flow that have erased the genetic signatures, if ever existed, in high dispersers. Of the four species with structure across the break, only two had significant albeit very low levels of asymmetric migration across the transition <span class="hlt">zone</span>. Historic processes have led to the current biogeographic and phylogeographic structure of marine species with limited dispersal along the north-central coast of <span class="hlt">Chile</span>, with a strong lasting impact in their genetic structure. PMID:24586356</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S41C0801S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S41C0801S"><span>The Effect of Earthquakes on Episodic Tremor and Slip Events on the <span class="hlt">Southern</span> Cascadia Subduction <span class="hlt">Zone</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sainvil, A. K.; Schmidt, D. A.; Nuyen, C.</p> <p>2017-12-01</p> <p>The goal of this study is to explore how slow slip events on the <span class="hlt">southern</span> Cascadia Subduction <span class="hlt">Zone</span> respond to nearby, offshore earthquakes by examining GPS and tremor data. At intermediate depths on the plate interface ( 40 km), transient fault slip is observed in the form of Episodic Tremor and Slip (ETS) events. These ETS events occur regularly (every 10 months), and have a longer duration than normal earthquakes. Researchers have been documenting slow slip events through data obtained by continuously running GPS stations in the Pacific Northwest. Some studies have proposed that pore fluid may play a role in these ETS events by lowering the effective stress on the fault. The interaction of earthquakes and ETS can provide constraints on the strength of the fault and the level of stress needed to alter ETS behavior. Earthquakes can trigger ETS events, but the connection between these events and earthquake activity is less understood. We originally hypothesized that ETS events would be affected by earthquakes in <span class="hlt">southern</span> Cascadia, and could result in a shift in the recurrence interval of ETS events. ETS events were cataloged using GPS time series provided by PANGA, in conjunction with tremor positions, in <span class="hlt">Southern</span> Cascadia for stations YBHB and DDSN from 1997 to 2017. We looked for evidence of change from three offshore earthquakes that occurred near the Mendocino Triple Junction with moment magnitudes of 7.2 in 2005, 6.5 in 2010, and 6.8 in 2014. Our results showed that the recurrence interval of ETS for stations YBHB and DDSN was not altered by the three earthquake events. Future is needed to explore whether this lack of interaction is explained by the non-optimal orientation of the receiver fault for the earthquake focal mechanisms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12414307','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12414307"><span>Phylogenetic and biogeographic relationships of the mouse opossum Thylamys (Didelphimorphia, Didelphidae) in <span class="hlt">southern</span> South America.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Eduardo Palma, R; Rivera-Milla, Eric; Yates, Terry L; Marquet, Pablo A; Meynard, Andrés P</p> <p>2002-11-01</p> <p>Nucleotide sequence data from the mitochondrial cytochrome b gene were used to evaluate the phylogenetic relationships among mouse opossum species of the genus Thylamys. Based on approximately 1000 bp in five of the six species of the genus and including different localities for some of the species, we concluded that T. macrura from the subtropical forests of eastern Paraguay is the most primitive taxon. Subsequent radiation of the genus is explained mainly via founder effect speciation. This evolutionary scenario would account for the speciation of T. pusilla, T. venusta, T. pallidior, and T. elegans in the Chaco, <span class="hlt">southern</span> Bolivia and northern Argentina, the Andean Altiplano, the Coastal Desert of <span class="hlt">Chile</span>, and coastal Perú, respectively. Calibration of a molecular clock set the Pleistocene as the period for the differentiation of Thylamys species. The molecular results confirm the strong genetic connection between populations that inhabit the "pre-cordillera" of northern <span class="hlt">Chile</span> (T. pallidior) and the canyons that run through the Atacama Desert to the lowlands in northern <span class="hlt">Chile</span>. Our results confirm the occurrence of two Thylamys species in <span class="hlt">Chile</span>, T. pallidior and T. elegans, within and south to the Atacama Desert, respectively. Copyright 2002 Elsevier Science (USA)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015IAUGA..2227893P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015IAUGA..2227893P"><span>The 2015 <span class="hlt">Chile</span>-U.S. Astronomy Education Outreach Summit in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Preston, Sandra Lee; Arnett, Dinah; Hardy, Eduardo; Cabezón, Sergio; Spuck, Tim; Fields, Mary Sue; Smith, R. Chris</p> <p>2015-08-01</p> <p>The first <span class="hlt">Chile</span>-U.S. Astronomy Education Outreach Summit occurred March 22-28, 2015. The Summit was organized and supported by the U.S. Embassy in <span class="hlt">Chile</span>, Associated Universities Inc., Association of Universities for Research in Astronomy, the Carnegie Institution for Science, the Image of <span class="hlt">Chile</span> Foundation, the National Science Foundation, and La Comisión Nacional de Investigación Científica y Tecnológica. The Summit brought together a team of leading experts and officials from <span class="hlt">Chile</span> and the U.S. to share best practices in astronomy education and outreach. In addition, Summit participants discussed enhancing existing partnerships, and building new collaborations between U.S. Observatories and astronomy education outreach leaders in <span class="hlt">Chile</span>.The Summit was an exciting and intense week of work and travel. Discussions opened in Santiago on March 22 with a variety of astronomy education and public outreach work sessions, a public forum, and on March 23 the U.S. Embassy sponsored a Star Party. On Tuesday, March 24, the Summit moved to San Pedro de Atacama, where activities included work sessions, a visit to the Atacama Large Millimeter/Submillimeter Array telescope facilities, and a second public forum. From San Pedro, the team traveled to La Serena for additional work sessions, visits to Gemini and Cerro Tololo, a third public forum, and the closing session. At each stop, authorities and the broader community were invited to participate and provide valuable input on the current state, and the future, of astronomy education and public outreach.Following the Summit a core working committee has continued meeting to draft a “roadmap document” based on findings from the Summit. This document will help to identify potential gaps in astronomy outreach efforts, and how the U.S. facilities and Chilean institutions might work together strategically to address these needs. The first draft of this “roadmap document” will be made available for comment in both Spanish and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA153978','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA153978"><span>Studies to Control Endemic Typhoid Fever in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1982-01-29</p> <p>de las colecistopatias en <span class="hlt">Chile</span> . Rev.Med.<span class="hlt">Chile</span> 100:1376- 1381, 1972. 8. Medina, E., Kaempffer, A.M., DeCroizet, V.A., Yrrazaval, Toporowicz, M...Epidemoologia de las colecistopatias en <span class="hlt">Chile</span> . II. Factores de importancia en estudios de autopsia. Rev.Med.<span class="hlt">Chile</span> 100:1382-1389, 1972. 9. Marinovio, I...necesario ef ec tuar previamente ex5menes bactereol.’gicos de inocuidad y potencia_ de la vacuna en el Instituto de Salud Priblica de</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19646306','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19646306"><span>Parasite communities of a fish assemblage from the intertidal rocky <span class="hlt">zone</span> of central <span class="hlt">Chile</span>: similarity and host specificity between temporal and resident fish.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Muñoz, G; Cortés, Y</p> <p>2009-09-01</p> <p>The different species of a fish assemblage can, to some extent, be similar in terms of their parasite communities, which can be associated with certain ecological host traits. This study compared the parasite community descriptors between temporal and resident fish species composing an intertidal assemblage from central <span class="hlt">Chile</span>. Host specificity and similarity indices of parasite communities among the fish species were also considered. A total of 1097 fish representing 14 species were collected during spring and summer of 2 consecutive years. A total spectrum of 40 parasite species was found, of which copepods and trematodes were the commonest. Congeneric fish species had the highest similarities in their parasite communities. Based on a cluster analysis, using only some fish species, no group was distinguished using abundance or prevalence of parasites, because 50% of parasite species had high host specificity and only few of them were shared among fish species. Adult parasites showed high host specificity and were found mainly in resident intertidal fish, whereas the temporal fish had parasites with different degrees of specificity. Consequently, resident intertidal fish were characterized by their own parasite species, meaning that their transmissions might be restricted to the intertidal <span class="hlt">zone</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Tectp.705...93S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Tectp.705...93S"><span>Observations of SKS splitting beneath the Central and <span class="hlt">Southern</span> External Dinarides in the Adria-Eurasia convergence <span class="hlt">zone</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Subašić, Senad; Prevolnik, Snježan; Herak, Davorka; Herak, Marijan</p> <p>2017-05-01</p> <p>Seismic anisotropy beneath the greater region of the Central and <span class="hlt">Southern</span> External Dinarides is estimated from observations of SKS splitting. The area is located in the broad and complex Africa-Eurasia convergent plate boundary <span class="hlt">zone</span>, where the Adriatic microplate interacts with the Dinarides. We analyzed recordings of 12 broadband seismic stations located in the Croatian coastal region. Evidence of seismic anisotropy was found beneath all stations. Fast axis directions are oriented approximately in the NE-SW to NNE-SSW direction, perpendicularly to the strike of the Dinarides. Average delay times range between 0.6 and 1.0 s. A counter-clockwise rotation in average fast axis directions was observed for the stations in the northern part with respect to the stations in the <span class="hlt">southern</span> part of the studied area. Fast axis directions coincide with the assumed direction of asthenospheric flow through a slab-gap below the Northern and Central External Dinarides, with the maximum tectonic stress orientation in the crust, and with fast directions of Pg and Sg-waves in the crust. These observations suggest that the detected SKS birefringence is primarily caused by the preferred lattice orientation of mantle minerals generated by the asthenospheric flow directed SW-NE to SSW-NNE, with a possible contribution from the crust.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006GeoRL..3320601P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006GeoRL..3320601P"><span>Maintaining of the Eastern South Pacific Oxygen Minimum <span class="hlt">Zone</span> (OMZ) off <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paulmier, A.; Ruiz-Pino, D.; Garçon, V.; Farías, L.</p> <p>2006-10-01</p> <p>Processes regulating OMZs persistence in the oxygenated ocean remain poorly understood. Four cruises (21°-30°S) and fixed-point monitoring (36°S) between 2000 and 2002 using techniques adapted to O2 conditions as low as 1 μM allow a preliminary analysis of the entire Chilean OMZ structure. A shallow OMZ is observed in the three studied areas, although its structure differs. Off northern and central <span class="hlt">Chile</span>, the OMZ is a permanent feature, more pronounced at the coast than further offshore. On the shelf, it forms in spring and erodes in fall. A conceptual model of two intermittent active or passive phases (intense or low biogeochemical O2 consumption) is proposed as a key mechanism for the local OMZ maintaining. The highest O2 consumptions are paradoxically favoured at the oxycline when the OMZ is less intense as offshore and on the shelf in spring and fall, suggesting a control by O2 availability of the OMZ remineralization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994Tecto..13..421T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994Tecto..13..421T"><span>Magma-assisted strain localization in an orogen-parallel transcurrent shear <span class="hlt">zone</span> of <span class="hlt">southern</span> Brazil</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tommasi, AndréA.; Vauchez, Alain; Femandes, Luis A. D.; Porcher, Carla C.</p> <p>1994-04-01</p> <p>In a lithospheric-scale, orogen-parallel transcurrent shear <span class="hlt">zone</span> of the Pan-African Dom Feliciano belt of <span class="hlt">southern</span> Brazil, two successive generations of magmas, an early calc-alkaline and a late peraluminous, have been emplaced during deformation. Microstructures show that these granitoids experienced a progressive deformation from magmatic to solid state under decreasing temperature conditions. Magmatic deformation is indicated by the coexistence of aligned K-feldspar, plagioclase, micas, and/or tourmaline with undeformed quartz. Submagmatic deformation is characterized by strain features, such as fractures, lattice bending, or replacement reactions affecting only the early crystallized phases. High-temperature solid-state deformation is characterized by extensive grain boundary migration in quartz, myrmekitic K-feldspar replacement, and dynamic recrystallization of both K-feldspar and plagioclase. Decreasing temperature during solid-state deformation is inferred from changes in quartz crystallographic fabrics, decrease in grain size of recrystallized feldspars, and lower Ti amount in recrystallized biotites. Final low-temperature deformation is characterized by feldspar replacement by micas. The geochemical evolution of the synkinematic magmatism, from calc-alkaline metaluminous granodiorites with intermediate 87Sr/86Sr initial ratio to peraluminous granites with very high 87Sr/86Sr initial ratio, suggests an early lower crustal source or a mixed mantle/crustal source, followed by a middle to upper crustal source for the melts. Shearing in lithospheric faults may induce partial melting in the lower crust by shear heating in the upper mantle, but, whatever the process initiating partial melting, lithospheric transcurrent shear <span class="hlt">zones</span> may collect melt at different depths. Because they enhance the vertical permeability of the crust, these <span class="hlt">zones</span> may then act as heat conductors (by advection), promoting an upward propagation of partial melting in the crust</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-11-28/pdf/2012-28790.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-11-28/pdf/2012-28790.pdf"><span>77 FR 70964 - Security <span class="hlt">Zone</span>, Potomac and Anacostia Rivers; Washington, DC</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-11-28</p> <p>... 1625-AA87 Security <span class="hlt">Zone</span>, Potomac and Anacostia Rivers; Washington, DC AGENCY: Coast Guard, DHS. ACTION... to establish a security <span class="hlt">zone</span> during activities associated with the Presidential Inauguration in... extends the <span class="hlt">southern</span> boundary of the proposed security <span class="hlt">zone</span>. This rule prohibits vessels and people from...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S31B4401N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S31B4401N"><span>Lithospheric Deformation Along the <span class="hlt">Southern</span> and Western Suture <span class="hlt">Zones</span> of the Wyoming Province</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nuyen, C.; Porritt, R. W.; O'Driscoll, L.</p> <p>2014-12-01</p> <p>The Wyoming Province is an Archean craton that played an early role in the construction and growth of the North American continent. This region, which encompasses the majority of modern day Wyoming and <span class="hlt">southern</span> Montana, initially collided with other Archean blocks in the Paleoproterozoic (2.0-1.8 Ga), creating the Canadian Shield. From 1.8-1.68 Ga, the Yavapai Province crashed into the Wyoming Province, suturing the two together. The accretion of the Yavapai Province gave way to the Cheyenne Belt, a deformational <span class="hlt">zone</span> that exists along the <span class="hlt">southern</span> border of the Wyoming Province where earlier studies have found evidence for crustal imbrication and double a Moho. Current deformation within the Wyoming province is due to its interaction with the Yellowstone Hotspot, which is currently located in the northwest portion of the region. This study images the LAB along the western and <span class="hlt">southern</span> borders of the Wyoming Province in order to understand how the region's Archean lithosphere has responded to deformation over time. These results shed light on the inherent strength of Archean cratonic lithosphere in general. We employ two methods for this study: common conversion point (CCP) stacking of S to P receiver functions and teleseismic and ambient Rayleigh wave dispersion. The former is used to image the LAB structure while the latter is used to create a velocity gradient for the region. Results from both of the methods reveal a notably shallower LAB depth to the west of the boundary. The shallower LAB west of the Wyoming Province is interpreted to be a result of lithospheric thinning due to the region's interaction with the Yellowstone Hotspot and post-Laramide deformation and extension of the western United States. We interpret the deeper LAB east of the boundary to be evidence for the Wyoming Province's resistance to lithospheric deformation from the hotspot and tectonic processes. CCP images across the Cheyenne Belt also reveal a shallower LAB under the western</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25250657','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25250657"><span>Comparative assessment of genetic and morphological variation at an extensive hybrid <span class="hlt">zone</span> between two wild cats in <span class="hlt">southern</span> Brazil.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Trigo, Tatiane C; Tirelli, Flávia P; de Freitas, Thales R O; Eizirik, Eduardo</p> <p>2014-01-01</p> <p>Increased attention towards the Neotropical cats Leopardus guttulus and L. geoffroyi was prompted after genetic studies identified the occurrence of extensive hybridization between them at their geographic contact <span class="hlt">zone</span> in <span class="hlt">southern</span> Brazil. This is a region where two biomes intersect, each of which is associated with one of the hybridizing species (Atlantic Forest with L. guttulus and Pampas with L. geoffroyi). In this study, we conducted in-depth analyses of multiple molecular markers aiming to characterize the magnitude and spatial structure of this hybrid <span class="hlt">zone</span>. We also performed a morphological assessment of these species, aiming to test their phenotypic differentiation at the contact <span class="hlt">zone</span>, as well as the correlation between morphological features and the admixture status of the individuals. We found strong evidence for extensive and complex hybridization, with at least 40% of the individuals sampled in Rio Grande do Sul state (southernmost Brazil) identified as hybrids resulting from post-F1 generations. Despite such a high level of hybridization, samples collected in this state still comprised two recognizable clusters (genetically and morphologically). Genetically pure individuals were sampled mainly in regions farther from the contact <span class="hlt">zone</span>, while hybrids concentrated in a central region (exactly at the interface between the two biomes). The morphological data set also revealed a strong spatial structure, which was correlated with the molecular results but displayed an even more marked separation between the clusters. Hybrids often did not present intermediate body sizes and could not be clearly distinguished morphologically from the parental forms. This observation suggests that some selective pressure may be acting on the hybrids, limiting their dispersal away from the hybrid <span class="hlt">zone</span> and perhaps favoring genomic combinations that maintain adaptive phenotypic features of one or the other parental species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4177223','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4177223"><span>Comparative Assessment of Genetic and Morphological Variation at an Extensive Hybrid <span class="hlt">Zone</span> between Two Wild Cats in <span class="hlt">Southern</span> Brazil</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Trigo, Tatiane C.; Tirelli, Flávia P.; de Freitas, Thales R. O.; Eizirik, Eduardo</p> <p>2014-01-01</p> <p>Increased attention towards the Neotropical cats Leopardus guttulus and L. geoffroyi was prompted after genetic studies identified the occurrence of extensive hybridization between them at their geographic contact <span class="hlt">zone</span> in <span class="hlt">southern</span> Brazil. This is a region where two biomes intersect, each of which is associated with one of the hybridizing species (Atlantic Forest with L. guttulus and Pampas with L. geoffroyi). In this study, we conducted in-depth analyses of multiple molecular markers aiming to characterize the magnitude and spatial structure of this hybrid <span class="hlt">zone</span>. We also performed a morphological assessment of these species, aiming to test their phenotypic differentiation at the contact <span class="hlt">zone</span>, as well as the correlation between morphological features and the admixture status of the individuals. We found strong evidence for extensive and complex hybridization, with at least 40% of the individuals sampled in Rio Grande do Sul state (southernmost Brazil) identified as hybrids resulting from post-F1 generations. Despite such a high level of hybridization, samples collected in this state still comprised two recognizable clusters (genetically and morphologically). Genetically pure individuals were sampled mainly in regions farther from the contact <span class="hlt">zone</span>, while hybrids concentrated in a central region (exactly at the interface between the two biomes). The morphological data set also revealed a strong spatial structure, which was correlated with the molecular results but displayed an even more marked separation between the clusters. Hybrids often did not present intermediate body sizes and could not be clearly distinguished morphologically from the parental forms. This observation suggests that some selective pressure may be acting on the hybrids, limiting their dispersal away from the hybrid <span class="hlt">zone</span> and perhaps favoring genomic combinations that maintain adaptive phenotypic features of one or the other parental species. PMID:25250657</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19301766','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19301766"><span>[Papillomavirus and cervical cancer in <span class="hlt">Chile</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>O'Ryan, Miguel; Valenzuela, María Teresa</p> <p>2008-11-01</p> <p>Molecular, clinical and epidemiological studies have established beyond doubt that human papiloma viruses (HPV) cause cervical cancer. The virus is also associated with genital warts and other less common cancers in oropharynx, vulva, vagina and penis. Worldwide, VPH genotypes 16 and 18 are the most common high risk genotypes, detected in near 70% of women with cervical cancer. The discovery of a cause-effect relationship between several carcinogenic microorganisms and cancer open avenues for new diagnostic, treatment and prevention strategies. In this issue of Revista Médica de <span class="hlt">Chile</span>, two papers on HPV are presented. Guzman and colleagues demonstrate that HPV can be detected in 66% to 77% of healthy male adolescents bypolymerase chain reaction and that positivity depends on the site of the penis that is sampled. These results support the role of male to female transmission of high risk HPVs in <span class="hlt">Chile</span> and should lead to even more active educational campaigns. The second paper provides recommendations for HPV vaccine use in <span class="hlt">Chile</span>, generated by the Immunization Advisory Committee of the Chilean Infectious Disease Society. To issue these recommendations, the Committee analyzes the epidemiological information available on HPV infection and cervical cancer in <span class="hlt">Chile</span>, vaccine safety and effectiveness data, and describes cost-effectiveness studies. Taking into account that universal vaccination is controversial, the Committee favors vaccine use in <span class="hlt">Chile</span> and it's incorporation into a national program. However, there is an indication that the country requires the implementation of an integrated surveillance approach including cross matching of data obtained from HPV genotype surveillance, monitoring of vaccination coverage, and surveillance of cervical cancer. The final decision of universal vaccine use in <span class="hlt">Chile</span> should be based on a through analysis of information.ev Mid <span class="hlt">Chile</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA358983','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA358983"><span><span class="hlt">Chile</span>: Civil-Military Relations and Democratic Consolidation</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1998-12-01</p> <p>Publishers, 1992), 41. 26 Javier Martinez and Alvaro Diaz , <span class="hlt">Chile</span> The Great Transformation (Harrisonburg, Virginia: The Brookings Institution, 1996...the world economy, by means of technological advancements, makes it necessary to reduce 32 Javier Martinez and Alvaro Diaz , <span class="hlt">Chile</span> the Great...disapproves the executive’s budget. There is no 60 Alicia Frohman, "<span class="hlt">Chile</span>: External Actors and the Transition to Democracy," in Beyond Sovereignty</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/fs/2010/3023/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/fs/2010/3023/"><span>A Magnitude 7.1 Earthquake in the Tacoma Fault <span class="hlt">Zone</span>-A Plausible Scenario for the <span class="hlt">Southern</span> Puget Sound Region, Washington</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gomberg, Joan; Sherrod, Brian; Weaver, Craig; Frankel, Art</p> <p>2010-01-01</p> <p>The U.S. Geological Survey and cooperating scientists have recently assessed the effects of a magnitude 7.1 earthquake on the Tacoma Fault <span class="hlt">Zone</span> in Pierce County, Washington. A quake of comparable magnitude struck the <span class="hlt">southern</span> Puget Sound region about 1,100 years ago, and similar earthquakes are almost certain to occur in the future. The region is now home to hundreds of thousands of people, who would be at risk from the shaking, liquefaction, landsliding, and tsunamis caused by such an earthquake. The modeled effects of this scenario earthquake will help emergency planners and residents of the region prepare for future quakes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1817487H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1817487H"><span>Impact of Intrathermocline eddies on seamount and oceanic island off Central <span class="hlt">Chile</span>: Observation and modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hormazabal, Samuel; Morales, Carmen; Cornejo, Marcela; Bento, Joaquim; Valencia, Luis; Auger, Pierre; Rodriguez, Angel; Correa, Marco; Anabalón, Valeria; Silva, Nelson</p> <p>2016-04-01</p> <p>In the Southeast Pacific, oceanographic processes that sustain the biological production necessary to maintain the ecosystems associated to seamounts and oceanic islands are still poorly understood. Recent studies suggest that the interaction of mesoscale and submesoescale eddies with oceanic islands and seamounts could be playing an important role in the time-space variability of primary production. In this work, research cruises, satellite data and Regional Ocean Modeling System (ROMS) results have been used to describe the main characteristics of intrathermocline eddies (ITE) and their impact on the Juan Fernández archipelago (JFA), off central <span class="hlt">Chile</span>. The JFA is located off the coast of central <span class="hlt">Chile</span> (33°S), and is composed of three main islands: Robinson Crusoe (RC), Alejandro Selkirk (AS) and Santa Clara (SC). Between the RC and AS are located the westernmost seamounts (JF6 and JF5) of the Juan Fernández archipelago. Satellite altimetry data (sea surface height from AVISO) were used to detect and track mesoscale eddies through eddy-tracking algorithm. Physical, chemical and biological parameters as temperature, salinity, dissolved oxygen and fluorescence were measured in the water column at JF5 and JF6, and along the coast off central <span class="hlt">Chile</span> (30-40°S). Results from the research cruise exhibit the interaction between an ITE and the seamount JF6. Eddy-tracking results showed that the ITE observed at the JF6 was formed at the coast off central-<span class="hlt">southern</span> <span class="hlt">Chile</span>, traveled ~900 km seaward and after ~9 months reached the JF5 and JF6 region. Observations along the Chilean coast confirmed that the coast corresponds to the formation area of the observed ITE. In this region, ITEs are represented by subsurface lenses (~100 km diameter; 400 m thickness) of homogeneous salinity, nutrient rich and oxygen-poor equatorial subsurface water mass (ESSW) which is transported poleward by the Peru-<span class="hlt">Chile</span> undercurrent in the coastal band and seaward by ITEs. The effect of ITEs on the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/21040','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/21040"><span>Detection of brown-rot antigens in <span class="hlt">southern</span> pine</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Carol A. Clausen</p> <p>1996-01-01</p> <p>Brown-rot fungal antigens were detected by particle capture immunoassay(PCI) in <span class="hlt">southern</span> pine 2 X 4’s beyond visible or culturable hyphal growth. Further analysis of test samples revealed changes along the 2 X 4’s that could be grouped into <span class="hlt">zones</span>. <span class="hlt">Zone</span> 1, the point of inoculation through 6 cm, showed low pH, measurable oxalic acid, high moisture, and high protein. <span class="hlt">Zone</span>...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/22125','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/22125"><span>Ecological <span class="hlt">zones</span> in the <span class="hlt">Southern</span> Appalachians: first approximation</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Steven A. Simon; Thomas K. Collins; Gary L. Kauffman; W. Henry McNab; Christopher J. Ulrey</p> <p>2005-01-01</p> <p>Forest environments of the <span class="hlt">Southern</span> Appalachian Mountains and their characteristic plant communities are among the most varied in the Eastern United States. Considerable data are available on the distribution of plant communities relative to temperature and moisture regimes, but not much information on fertility as an environmental influence has been published; nor has...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5673839','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5673839"><span>Morphological analysis of Trichomycterus areolatus Valenciennes, 1846 from <span class="hlt">southern</span> Chilean rivers using a truss-based system (Siluriformes, Trichomycteridae)</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Colihueque, Nelson; Corrales, Olga; Yáñez, Miguel</p> <p>2017-01-01</p> <p>Abstract Trichomycterus areolatus Valenciennes, 1846 is a small endemic catfish inhabiting the Andean river basins of <span class="hlt">Chile</span>. In this study, the morphological variability of three T. areolatus populations, collected in two river basins from <span class="hlt">southern</span> <span class="hlt">Chile</span>, was assessed with multivariate analyses, including principal component analysis (PCA) and discriminant function analysis (DFA). It is hypothesized that populations must segregate morphologically from each other based on the river basin that they were sampled from, since each basin presents relatively particular hydrological characteristics. Significant morphological differences among the three populations were found with PCA (ANOSIM test, r = 0.552, p < 0.0001) and DFA (Wilks’s λ = 0.036, p < 0.01). PCA accounted for a total variation of 56.16% by the first two principal components. The first Principal Component (PC1) and PC2 explained 34.72 and 21.44% of the total variation, respectively. The scatter-plot of the first two discriminant functions (DF1 on DF2) also validated the existence of three different populations. In group classification using DFA, 93.3% of the specimens were correctly-classified into their original populations. Of the total of 22 transformed truss measurements, 17 exhibited highly significant (p < 0.01) differences among populations. The data support the existence of T. areolatus morphological variation across different rivers in <span class="hlt">southern</span> <span class="hlt">Chile</span>, likely reflecting the geographic isolation underlying population structure of the species. PMID:29134012</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29134012','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29134012"><span>Morphological analysis of Trichomycterus areolatus Valenciennes, 1846 from <span class="hlt">southern</span> Chilean rivers using a truss-based system (Siluriformes, Trichomycteridae).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Colihueque, Nelson; Corrales, Olga; Yáñez, Miguel</p> <p>2017-01-01</p> <p>Trichomycterus areolatus Valenciennes, 1846 is a small endemic catfish inhabiting the Andean river basins of <span class="hlt">Chile</span>. In this study, the morphological variability of three T. areolatus populations, collected in two river basins from <span class="hlt">southern</span> <span class="hlt">Chile</span>, was assessed with multivariate analyses, including principal component analysis (PCA) and discriminant function analysis (DFA). It is hypothesized that populations must segregate morphologically from each other based on the river basin that they were sampled from, since each basin presents relatively particular hydrological characteristics. Significant morphological differences among the three populations were found with PCA (ANOSIM test, r = 0.552, p < 0.0001) and DFA (Wilks's λ = 0.036, p < 0.01). PCA accounted for a total variation of 56.16% by the first two principal components. The first Principal Component (PC1) and PC2 explained 34.72 and 21.44% of the total variation, respectively. The scatter-plot of the first two discriminant functions (DF1 on DF2) also validated the existence of three different populations. In group classification using DFA, 93.3% of the specimens were correctly-classified into their original populations. Of the total of 22 transformed truss measurements, 17 exhibited highly significant ( p < 0.01) differences among populations. The data support the existence of T. areolatus morphological variation across different rivers in <span class="hlt">southern</span> <span class="hlt">Chile</span>, likely reflecting the geographic isolation underlying population structure of the species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18949193','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18949193"><span>[A scientometric view of Revista Médica de <span class="hlt">Chile</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Krauskopf, Manuel; Krauskopf, Erwin</p> <p>2008-08-01</p> <p>During the last decade Revista Médica de <span class="hlt">Chile</span> increased its visibility, measured on citations and impact factor. To perform a scientometric analysis to assess the performance of Revista Médica de <span class="hlt">Chile</span>. Thomson's-ISI Web of Science and Journal Citation Reports QCR) were consulted for performance indicators of Revista Médica de <span class="hlt">Chile</span> and Latin American journals whose subject is General and Internal Medicine. We also report the h-index of the journal, which infers quality linked to the quantity of the output. According to the h-index, Revista Médica de <span class="hlt">Chile</span> ranks 4 among the 36 journals indexed and published by Argentina, Brazil, <span class="hlt">Chile</span> and México. The top ten articles published by Revista Médica de <span class="hlt">Chile</span> and the institutions with the higher contribution to the journal, were identified using citations. In the Latin American region, Brazil relevantly increased its scientific output. However, Argentina, <span class="hlt">Chile</span> and México maintain a plateau during the last decade. Revista Médica de <span class="hlt">Chile</span> increased notoriously its performance. Its contribution to the Chilean scientific community dedicated to Medicine appears to be of central value.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Tectp.681..135A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Tectp.681..135A"><span>The Galicia-Ossa-Morena <span class="hlt">Zone</span>: Proposal for a new <span class="hlt">zone</span> of the Iberian Massif. Variscan implications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arenas, Ricardo; Díez Fernández, Rubén; Rubio Pascual, Francisco J.; Sánchez Martínez, Sonia; Martín Parra, Luis Miguel; Matas, Jerónimo; González del Tánago, José; Jiménez-Díaz, Alberto; Fuenlabrada, Jose M.; Andonaegui, Pilar; Garcia-Casco, Antonio</p> <p>2016-06-01</p> <p>Correlation of a group of allochthonous terranes (referred to as basal, ophiolitic and upper units) exposed in the NW and SW of the Iberian Massif, is used to propose a new geotectonic <span class="hlt">zone</span> in the <span class="hlt">southern</span> branch of the Variscan Orogen: the Galicia-Ossa-Morena <span class="hlt">Zone</span>. Recent advances in SW Iberia identify most of the former Ossa-Morena <span class="hlt">Zone</span> as another allochthonous complex of the Iberian Massif, the Ossa-Morena Complex, equivalent to the Cabo Ortegal, Órdenes, Malpica-Tui, Bragança and Morais complexes described in NW Iberia. The new geotectonic <span class="hlt">zone</span> and its counterparts along the rest of the Variscan Orogen constitute an Internal Variscan <span class="hlt">Zone</span> with ophiolites and units affected by high-P metamorphism. The Galicia-Ossa-Morena <span class="hlt">Zone</span> includes a Variscan suture and pieces of continental crust bearing the imprint of Ediacaran-Cambrian events related to the activity of peri-Gondwanan magmatic arcs (Cadomian orogenesis). In the Iberian Massif, the general structure of this geotectonic <span class="hlt">zone</span> represents a duplication of the Gondwanan platform, the outboard sections being juxtaposed on top of domains located closer to the mainland before amalgamation. This interpretation offers an explanation that overcomes some issues regarding the differences between the stratigraphic and paleontological record of the central and <span class="hlt">southern</span> sections of the Iberian Massif. Also, equivalent structural relationships between other major geotectonic domains of the rest of the Variscan Orogen are consistent with our interpretation and allow suspecting similar configurations along strike of the orogen. A number of issues may be put forward in this respect that potentially open new lines of thinking about the architecture of the Variscan Orogen.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JSAES..15..285F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JSAES..15..285F"><span>A new fossil mammal assemblage from the <span class="hlt">southern</span> Chilean Andes: implications for geology, geochronology, and tectonics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Flynn, John J.; Novacek, Michael J.; Dodson, Holly E.; Frassinetti, Daniel; McKenna, Malcolm C.; Norell, Mark A.; Sears, Karen E.; Swisher, Carl C.; Wyss, André R.</p> <p>2002-07-01</p> <p>A diverse (36 taxa), new fossil terrestrial mammal assemblage has been recovered from the Santacrucian South American Land Mammal 'Age' (SALMA; latest Early Miocene) in the <span class="hlt">southern</span> Andes of <span class="hlt">Chile</span>. This is the westernmost high latitude mammal fauna known in South America and the first in a string of new mammal assemblages discovered in <span class="hlt">Chile</span> after a lapse of nearly a century. The terrestrial mammal-bearing sequence conformably overlies a marine section of Late Oligocene to Early Miocene age. The combined marine-terrestrial sequence, as well as a locality with fossil whales and bracketing basalts, bear significantly on theories regarding the extent of the late Tertiary Patagonian epicontinental seaway and the onset of later Cenozoic phases of uplift in the <span class="hlt">southern</span> Andes. Uplift in this region likely began by Santacrucian SALMA (˜16-17.5 Ma) time, but it remains uncertain whether this occurred in two phases (Pehuenchic and Quechuic) or one. These discoveries substantiate propositions of sharp geologic contrasts north and south of the Lago General Carrera/Lago Buenos Aires area (Magellanes basin to the south and Río Mayo embayment to the north). Minimum estimates of uplift rate are approximately 0.05-0.07 mm/yr (but as high as 0.22 mm/yr), comparable to or slightly lower than those from other parts of the Andes (e.g. Bolivia). The timing and location of uplift may be correlated with major plate tectonic events associated with the <span class="hlt">Chile</span> Margin Triple Junction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://geoinfo.nmt.edu/publications/openfile/details.cfml?Volume=584','USGSPUBS'); return false;" href="https://geoinfo.nmt.edu/publications/openfile/details.cfml?Volume=584"><span>Geologic map and cross sections of the Embudo Fault <span class="hlt">Zone</span> in the <span class="hlt">Southern</span> Taos Valley, Taos County, New Mexico</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bauer, Paul W.; Kelson, Keith I.; Grauch, V.J.S.; Drenth, Benjamin J.; Johnson, Peggy S.; Aby, Scott B.; Felix, Brigitte</p> <p>2016-01-01</p> <p>The <span class="hlt">southern</span> Taos Valley encompasses the physiographic and geologic transition <span class="hlt">zone</span> between the Picuris Mountains and the San Luis Basin of the Rio Grande rift. The Embudo fault <span class="hlt">zone</span> is the rift transfer structure that has accommodated the kinematic disparities between the San Luis Basin and the Española Basin during Neogene rift extension. The eastern terminus of the transfer <span class="hlt">zone</span> coincides with the intersection of four major fault <span class="hlt">zones</span> (Embudo, Sangre de Cristo, Los Cordovas, and Picuris-Pecos), resulting in an area of extreme geologic and hydrogeologic complexities in both the basin-fill deposits and the bedrock. Although sections of the Embudo fault <span class="hlt">zone</span> are locally exposed in the bedrock of the Picuris Mountains and in the late Cenozoic sedimentary units along the top of the Picuris piedmont, the full proportions of the fault <span class="hlt">zone</span> have remained elusive due to a pervasive cover of Quaternary surficial deposits. We combined insights derived from the latest geologic mapping of the area with deep borehole data and high-resolution aeromagnetic and gravity models to develop a detailed stratigraphic/structural model of the rift basin in the <span class="hlt">southern</span> Taos Valley area. The four fault systems in the study area overlap in various ways in time and space. Our geologic model states that the Picuris-Pecos fault system exists in the basement rocks (Picuris formation and older units) of the rift, where it is progressively down dropped and offset to the west by each Embudo fault strand between the Picuris Mountains and the Rio Pueblo de Taos. In this model, the Miranda graben exists in the subsurface as a series of offset basement blocks between the Ponce de Leon neighborhood and the Rio Pueblo de Taos. In the study area, the Embudo faults are pervasive structures between the Picuris Mountains and the Rio Pueblo de Taos, affecting all geologic units that are older than the Quaternary surficial deposits. The Los Cordovas faults are thought to represent the late Tertiary to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24483088','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24483088"><span>[Characteristics and adaptation of seasonal drought in <span class="hlt">southern</span> China under the background of climate change. V. Seasonal drought characteristics division and assessment in <span class="hlt">southern</span> China].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huang, Wan-Hua; Sui, Yue; Yang, Xiao-Guang; Dai, Shu-Wei; Li, Mao-Song</p> <p>2013-10-01</p> <p><span class="hlt">Zoning</span> seasonal drought based on the study of drought characteristics can provide theoretical basis for formulating drought mitigation plans and improving disaster reduction technologies in different arid <span class="hlt">zones</span> under global climate change. Based on the National standard of meteorological drought indices and agricultural drought indices and the 1959-2008 meteorological data from 268 meteorological stations in <span class="hlt">southern</span> China, this paper analyzed the climatic background and distribution characteristics of seasonal drought in <span class="hlt">southern</span> China, and made a three-level division of seasonal drought in this region by the methods of combining comprehensive factors and main factors, stepwise screening indices, comprehensive disaster analysis, and clustering analysis. The first-level division was with the annual aridity index and seasonal aridity index as the main indices and with the precipitation during entire year and main crop growing season as the auxiliary indices, dividing the <span class="hlt">southern</span> China into four primary <span class="hlt">zones</span>, including semi-arid <span class="hlt">zone</span>, sub-humid <span class="hlt">zone</span>, humid <span class="hlt">zone</span>, and super-humid <span class="hlt">zone</span>. On this basis, the four primary <span class="hlt">zones</span> were subdivided into nine second-level <span class="hlt">zones</span>, including one semi-arid area-temperate-cold semi-arid hilly area in Sichuan-Yunnan Plateau, three sub-humid areas of warm sub-humid area in the north of the Yangtze River, warm-tropical sub-humid area in South China, and temperate-cold sub-humid plateau area in Southwest China, three humid areas of temperate-tropical humid area in the Yangtze River Basin, warm-tropical humid area in South China, and warm humid hilly area in Southwest China, and two super-humid areas of warm-tropical super-humid area in South China and temperate-cold super-humid hilly area in the south of the Yangtze River and Southwest China. According to the frequency and intensity of multiple drought indices, the second-level <span class="hlt">zones</span> were further divided into 29 third-level <span class="hlt">zones</span>. The distribution of each seasonal drought <span class="hlt">zone</span> was</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23347268','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23347268"><span>Co-infection patterns of infectious salmon anaemia and sea lice in farmed Atlantic salmon, Salmo salar L., in <span class="hlt">southern</span> <span class="hlt">Chile</span> (2007-2009).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Valdes-Donoso, P; Mardones, F O; Jarpa, M; Ulloa, M; Carpenter, T E; Perez, A M</p> <p>2013-03-01</p> <p>Infectious salmon anaemia virus (ISAV) caused a large epidemic in farmed Atlantic salmon in <span class="hlt">Chile</span> in 2007-2009. Here, we assessed co-infection patterns of ISAV and sea lice (SL) based on surveillance data collected by the fish health authority. ISAV status and SL counts in all Atlantic salmon farms located in the 10th region of <span class="hlt">Chile</span> were registered monthly from July 2007 through December 2009. Each farm was categorized monthly according to its ISAV and SL status. A multinomial time-space scan test using a circular window was applied to identify disease clusters, and a multivariate regression model was fitted to quantify the association between disease-clustering and farm-management factors. Most of the identified clusters (9/13) were associated with high SL burdens. There were significant associations (P < 0.05) between management factors and ISAV/SL status. Areas in which good management practices were associated with a reduced disease risk were identified. The findings of this study suggest that certain management practices can effectively reduce the risk of SL and ISAV in the face of an epidemic and will be helpful towards creating an effective disease control programme in <span class="hlt">Chile</span>. © 2013 Blackwell Publishing Ltd.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S21A4398L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S21A4398L"><span>Field survey of the 1 April 2014 Iquique tsunami along the coasts of <span class="hlt">Chile</span> and Peru</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lagos, M.; Fritz, H. M.</p> <p>2014-12-01</p> <p>On 1 April, 2014 a magnitude Mw 8.2 earthquake occurred off the coast of northern <span class="hlt">Chile</span> less than 100 km NW of Iquique within a region of historic quiescence termed the northern <span class="hlt">Chile</span> seismic gap. The ensuing tsunami inundation caused mostly minor damage centered in Iquique and neighbouring stretches of coastline. Fortunately, ancestral knowledge from the past 1868 and 1877 tsunamis in the region along with the recent 2010 Maule tsunami, as well as tsunami education and evacuation exercises prompted most coastal residents to spontaneously evacuate to high ground after the earthquake. There were no tsunami victims, while a handful of fatalities were associated to the earthquake and the tsunami evacuation. The local scientist deployed in the morning hours to start the tsunami survey in Iquique on the day after the earthquake. The international scientist joined the local effort from April 6 to 11. The international tsunami survey team (ITST) documented flow depths, runup heights, inundation distances, sediment deposition, damage patterns, performance of the navigation infrastructure and impact on the natural environment. The ITST covered a 700 km stretch of coastline from the Mejillones Peninsula (23.5° S) north of Antofagasta in <span class="hlt">Chile</span> up to Vila Vila (18.1° S) in <span class="hlt">southern</span> Peru. We surveyed 30 locations with differential GPS and laser range finders. The tsunami impact peaked in the vicinity of Iquique exceeding 4 m in tsunami height. A significant variation in tsunami impact was observed along the coastlines of <span class="hlt">Chile</span> and Peru both at local and regional scales. The tsunami occurred in the evening hours limiting the availability of eyewitness video footages. Observations from the 2014 <span class="hlt">Chile</span> tsunami are compared against the 1868, 1877 and 2010 <span class="hlt">Chile</span> tsunamis. Given the magnitude of the 1 April 2014 earthquake the tsunami could have been significantly larger. However the absence of a massive tsunami may mislead residents in the future to believe another minor tsunami</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...48.2569B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...48.2569B"><span>Interannual variability of the frontal activity in the <span class="hlt">Southern</span> Hemisphere: relationship with atmospheric circulation and precipitation over <span class="hlt">southern</span> South America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blázquez, Josefina; Solman, Silvina A.</p> <p>2017-04-01</p> <p>The interannual variability of the frontal activity over the western <span class="hlt">Southern</span> Hemisphere and its linkage with the variability of the atmospheric circulation and precipitation over <span class="hlt">southern</span> South America is studied. The analysis is focused on the austral winter and spring seasons. The frontal activity is represented by an index defined as the product between the horizontal gradient of temperature and the relative vorticity at 850 hPa (FI) and is computed from the ERA Interim and NCEP2 reanalysis. For the two seasons the main mode of variability of FI, as depicted by the first Empirical Orthogonal Function, presents centres of action located in the <span class="hlt">southern</span> part of the western <span class="hlt">Southern</span> Hemisphere. This pattern is present in the two reanalysis datasets. The correlation coefficients between the principal component of the leading mode of FI and the two main modes of the 500 hPa geopotential height indicate that both the ENSO-mode and the SAM modulate the leading pattern of FI in winter while during the spring season the ENSO-mode controls the FI variability. The variability of the FI has a robust influence on the interannual variability of precipitation over <span class="hlt">southern</span> South America and adjacent oceans. Over the continent, it was found that the pattern of precipitation anomalies associated with the variability of the FI depicts significant signals over southeastern South America (SESA), centre and south of <span class="hlt">Chile</span> for winter and over SESA and southeastern Brazil for spring and agrees with the pattern of the leading mode of precipitation variability over <span class="hlt">southern</span> South America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1094874.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1094874.pdf"><span>Where Do Mexico and <span class="hlt">Chile</span> Stand on Inclusive Education? Short Title: Inclusion in Mexico and <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>García-Cedillo, Ismael; Romero-Contreras, Silvia; Ramos-Abadie, Liliana</p> <p>2015-01-01</p> <p>This paper discusses the background, current situation and challenges of educational integration and inclusive education in Mexico and <span class="hlt">Chile</span>. These countries obtained similar low results on the academic achievement of their students (Mexico last and <span class="hlt">Chile</span> second last) among OECD countries; and above average scores, among Latin-American countries.…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5719539','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5719539"><span>Assessing the risk <span class="hlt">zones</span> of Chagas' disease in <span class="hlt">Chile</span>, in a world marked by global climatic change</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tapia-Garay, Valentina; Figueroa, Daniela P; Maldonado, Ana; Frías-Laserre, Daniel; Gonzalez, Christian R; Parra, Alonso; Canals, Lucia; Apt, Werner; Alvarado, Sergio; Cáceres, Dante; Canals, Mauricio</p> <p>2018-01-01</p> <p>BACKGROUND Vector transmission of Trypanosoma cruzi appears to be interrupted in <span class="hlt">Chile</span>; however, data show increasing incidence of Chagas' disease, raising concerns that there may be a reemerging problem. OBJECTIVE To estimate the actual risk in a changing world it is necessary to consider the historical vector distribution and correlate this distribution with the presence of cases and climate change. METHODS Potential distribution models of Triatoma infestans and Chagas disease were performed using Maxent, a machine-learning method. FINDINGS Climate change appears to play a major role in the reemergence of Chagas' disease and T. infestans in <span class="hlt">Chile</span>. The distribution of both T. infestans and Chagas' disease correlated with maximum temperature, and the precipitation during the driest month. The overlap of Chagas' disease and T. infestans distribution areas was high. The distribution of T. infestans, under two global change scenarios, showed a minimal reduction tendency in suitable areas. MAIN CONCLUSION The impact of temperature and precipitation on the distribution of T. infestans, as shown by the models, indicates the need for aggressive control efforts; the current control measures, including T. infestans control campaigns, should be maintained with the same intensity as they have at present, avoiding sylvatic foci, intrusions, and recolonisation of human dwellings. PMID:29211105</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70013840','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70013840"><span>Sr and Nd isotopic and trace element compositions of Quaternary volcanic centers of the <span class="hlt">Southern</span> Andes</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Futa, K.; Stern, C.R.</p> <p>1988-01-01</p> <p>Isotopic compositions of samples from six Quaternary volcanoes located in the northern and <span class="hlt">southern</span> extremities of the <span class="hlt">Southern</span> Volcanic <span class="hlt">Zone</span> (SVZ, 33-46??S) of the Andes and from four centers in the Austral Volcanic <span class="hlt">Zone</span> (AVZ, 49-54??S) range for 87Sr 86Sr from 0.70280 to 0.70591 and for 143Nd 144Nd from 0.51314 to 0.51255. The ranges are significantly greater than previously reported from the <span class="hlt">southern</span> Andes but are different from the isotopic compositions of volcanoes in the central and northern Andes. Basalts and basaltic andesites from three centers just north of the <span class="hlt">Chile</span> Rise-Trench triple junction have 87Sr 86Sr, 143Nd 144Nd, La Yb, Ba La, and Hf Lu that lie within the relatively restricted ranges of the basic magmas erupted from the volcanic centers as far north as 35??S in the SVZ of the Andes. The trace element and Sr and Nd isotopic characteristics of these magmas may be explained by source region contamination of subarc asthenosphere, with contaminants derived from subducted pelagic sediments and seawater-altered basalts by dehydration of subducted oceanic lithosphere. In the northern extremity of the SVZ between 33?? and 34??S, basaltic andesites and andesites have higher 87Sr 86Sr, Rb Cs, and Hf Lu, and lower 143Nd 144Nd than basalts and basaltic andesites erupted farther south in the SVZ, which suggests involvement of components derived from the continental crust. In the AVZ, the most primitive sample, high-Mg andesite from the southernmost volcanic center in the Andes (54??S) has Sr and Nd isotopic compositions and K Rb and Ba La similar to MORB. The high La Yb of this sample suggests formation by small degrees of partial melting of subducted MORB with garnet as a residue. Samples from centers farther north in the AVZ show a regionally regular northward increase in SiO2, K2O, Rb, Ba, Ba La, and 87Sr 86Sr and decrease in MgO, Sr, K Rb, Rb Cs, and 143Nd 144Nd, suggesting increasingly greater degrees of fractional crystallization and associated intra</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.V51F0426P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.V51F0426P"><span>Apatite Mineral Chemistry From IOA Deposits in Northern <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Palma, G.; Barra, F.; Reich, M.; Valencia, V.; Simon, A. C.; Vervoort, J. D.</p> <p>2017-12-01</p> <p>The Carmen, Fresia and Mariela iron-oxide apatite (IOA) deposits of Cretaceous age, located in the Coastal Cordillera of northern <span class="hlt">Chile</span>, comprise massive bodies of magnetite with minor apatite and actinolite crystals spatially related to diorite intrusions. In order to provide new insights on the origin of Andean IOA deposits, we provide geochemical data of apatite grains collected from these three deposits. All studied apatite grains are <span class="hlt">zoned</span> with respect to Cl and F, and show a decoupled behaviour between fluorapatite and chlorapatite. Carmen apatite grains are mostly F-rich, whereas in Mariela apatite grains are Cl-rich. Fresia apatite grains show a variable composition between fluorapatite and chlorapatite. Carmen apatite grains show a high REE content reaching up to 7000 ppm, and both Fresia and Mariela have lower REE content (<1400 ppm). REE patterns for all analyzed apatite grains show the typical LREE enrichment relative to the HREE and pronounced negative Eu anomaly, which indicates crystallization of plagioclase in the source magmas [1]. Chlorapatite <span class="hlt">zones</span> are characterized by high S, Na, Sr and Fe content relative to fluorapatite <span class="hlt">zones</span>. Notably S and Na show a coupled behaviour with Cl. Conversely LREE are depleted in chlorapatite <span class="hlt">zones</span>, which is compatible with metasomatism through dissolution-reprecipitation mechanism and formation of monazite inclusions [2]. These results indicate a magmatic origin for fluorapatite in these Andean IOA deposits followed by variable degrees of hydrothermal overprint which resulted in the formation of Cl-rich apatites.[1] Frietsch & Perdahl (1995) Ore Geology Rev. 9 489-510. [2]Harlov et al. (2005) Contrib Mineral Petrol 150: 268-286</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.T31E2958X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.T31E2958X"><span>Is the Vincent fault in <span class="hlt">southern</span> California the Laramide subduction <span class="hlt">zone</span> megathrust?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xia, H.; Platt, J. P.</p> <p>2016-12-01</p> <p>The Vincent fault (VF) in the San Gabriel Mountains, <span class="hlt">southern</span> California separates a Meso-Proterozoic gneiss complex and Mesozoic granitoid rocks in the upper plate from the ocean-affiliated Late Cretaceous Pelona schist in the lower plate, and it has been widely interpreted as the original Laramide subduction megathrust. A 500 to 1000 m thick mylonite <span class="hlt">zone</span>, consisting of a low-stress (LS) section at the bottom, a high-stress (HS) section at the top, and a weakly deformed section in between, is developed above the VF. Our kinematic, thermobarometric and geochronological analysis of the mylonite <span class="hlt">zone</span> indicates that the VF is a normal fault. Shear sense indicators including asymmetric porphyroblasts, quartz new grain fabric, mineral fish, and quartz CPO from the HS and the LS sections exhibit a top-to-SE sense of shear on the SW-dipping mylonitic foliation, which is contrary to what one would expect for the Laramide subduction megathrust. A few samples from the LS section were overprinted by HS microstructure, implying that the LS mylonites predate the HS mylonites. TitaniQ thermometer and Si-in-muscovite barometer show that the P-T conditions are 389 ± 6 °C, 5 kbar for the LS mylonites and 329 ± 6 °C, 2.4 kbar for HS mylonites. Considering the temporal sequence of HS and LS mylonites, they are likely to be formed during exhumation. A comparison with the lower plate leads to the same conclusion. The top 80-100 m of the Pelona schist underneath the VF is folded and also mylonitized, forming the Narrows synform and S3 simultaneously. Our previous study found that S3 of the Pelona schist has a top-to-SE sense of shear and similar P-T conditions as the LS mylonite in the upper plate, so S3 of the Pelona schist is likely to be formed together with the LS mylonites in the upper plate. While mylonitization of Pelona schist (S3) overprinted both the subduction-related S1 fabric and the return-flow-related S2 fabric, it is reasonable to argue that the mylonite <span class="hlt">zone</span> above</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.G41B..08T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.G41B..08T"><span>Megathrust earthquakes in Japan and <span class="hlt">Chile</span> triggered multiple volcanoes to subside</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takada, Y.; Pritchard, M. E.; Fukushima, Y.; Jay, J.; Aron, F. A.; Henderson, S.; Lara, L. E.</p> <p>2012-12-01</p> <p> volcanic subsidence in the same manner as Japan by removing the earthquake deformation signature. Most interferograms were created from ALOS data, but several were from ENVISAT and ERS-2. We find subsidence at five volcanic areas: Caldera del Atuel, Tinguiririca, Calabozos caldera, Cerro Azul, and Nevados de Chillán. All of these regions belong to the Andean <span class="hlt">Southern</span> Volcanic <span class="hlt">Zone</span>, and are located within the 400 km long rupture area of the Maule earthquake. In three of the five subsiding regions, there are known geothermal reservoirs. The orientation of N-S elongated subsidence areas can be explained by underlying hydrothermal and/or magmatic system and increase in the number of small cracks around those systems due to the coseismic stress disturbance. Existence of such damage <span class="hlt">zone</span> would make water and/or gas emissions efficient, and enhanced the N-S elongated surface subsidence. Increases in stream flow at the date of Maule earthquake were observed, although the fluid contribution from the volcanic areas is not the only or necessarily the primary source.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.7156G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.7156G"><span>Modern diatom assemblages as tools for paleoenvironmental reconstruction: a case study from estuarine intertidal <span class="hlt">zones</span> in <span class="hlt">southern</span> Iberia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gomes, Ana; Boski, Tomasz; Moura, Delminda; Szkornik, Katie; Witkowski, Andrzej; Connor, Simon; Laut, Lazaro; Sobrinho, Frederico; Oliveira, Sónia</p> <p>2017-04-01</p> <p>Diatoms are unicellular algae that live in saline, brackish and freshwater environments, either floating in the water column or associated with various substrates (e.g., muddy and sandy sediments). Diatoms are sensitive to changes in environmental variables such as salinity, sediment texture, nutrient availability, light and temperature. This characteristic, along with their short lifespan, allows diatoms to quickly respond to environmental changes. Since the beginning of the 20th century, diatoms have been widely used to study the Holocene evolution of estuaries worldwide, particularly to reconstruct ecological responses to sea-level and climate changes. However, diatoms have been poorly studied in estuarine intertidal <span class="hlt">zones</span>, due to the complexity of these environments, which have both fluvial and marine influences. The aim of this study was to understand diatom diversity and spatial distribution in intertidal <span class="hlt">zones</span> from two geomorphologically and hydrologically distinct estuaries. Sediment samples were collected from within the intertidal <span class="hlt">zones</span> along the Arade and Guadiana River estuaries in <span class="hlt">southern</span> Iberia. The sampling points embraced almost all the tidal and salinity gradients of both estuaries, capturing the highest possible environmental variability and hence of diatom assemblages. At each sampling point, the salinity and pH of the sediment interstitial water were measured. The sediment samples were subdivided for diatom identification, textural analysis and organic matter determination. All sampling points were georeferenced by DGPS and the duration of tidal inundation was calculated for each site. Following diatom identification, the data were analysed statistically (i.e. cluster analysis, PCA, DCA and RDA). The present study revealed that there is a great diatom diversity in both estuaries (418 species), with several species new to science. The most important diatom species (with abundances higher or equal to 5%) occur in five ecological groups, which are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27595942','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27595942"><span>Temporal variation on environmental variables and pollution indicators in marine sediments under sea Salmon farming cages in protected and exposed <span class="hlt">zones</span> in the Chilean inland <span class="hlt">Southern</span> Sea.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Urbina, Mauricio A</p> <p>2016-12-15</p> <p>The impacts of any activity on marine ecosystems will depend on the characteristics of the receptor medium and its resilience to external pressures. Salmon farming industry develops along a constant gradient of hydrodynamic conditions in the south of <span class="hlt">Chile</span>. However, the influence of the hydrodynamic characteristics (weak or strong) on the impacts of intensive salmon farming is still poorly understood. This one year study evaluates the impacts of salmon farming on the marine sediments of both protected and exposed marine <span class="hlt">zones</span> differing in their hydrodynamic characteristics. Six physico-chemical, five biological variables and seven indexes of marine sediments status were evaluated under the salmon farming cages and control sites. Our results identified a few key variables and indexes necessary to accurately evaluate the salmon farming impacts on both protected and exposed <span class="hlt">zones</span>. Interestingly, the ranking of importance of the variables and the temporality of the observed changes, varied depending on the hydrodynamic characteristics. Biological variables (nematodes abundance) and environmental indexes (Simpson's dominance, Shannon's diversity and Pielou evenness) are the first to reflect detrimental impacts under the salmon farming cages. Then the physico-chemical variables such as redox, sulphurs and phosphorus in both <span class="hlt">zones</span> also show detrimental impacts. Based on the present results we propose that the hydrodynamic regime is an important driver of the magnitude and temporality of the effects of salmon farming on marine sediments. The variables and indexes that best reflect the effects of salmon farming, in both protected and exposed <span class="hlt">zones</span>, are also described. Copyright © 2016. Published by Elsevier B.V.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26457694','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26457694"><span>Antibacterial Activity, Antioxidant Effect and Chemical Composition of Propolis from the Región del Maule, Central <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nina, Nélida; Quispe, Cristina; Jiménez-Aspee, Felipe; Theoduloz, Cristina; Feresín, Gabriela Egly; Lima, Beatriz; Leiva, Elba; Schmeda-Hirschmann, Guillermo</p> <p>2015-10-06</p> <p>Propolis is commercialized in <span class="hlt">Chile</span> as an antimicrobial agent. It is obtained mainly from central and <span class="hlt">southern</span> <span class="hlt">Chile</span>, but is used for the same purposes regardless of its origin. To compare the antimicrobial effect, the total phenolic (TP), the total flavonoid (TF) content and the phenolic composition, 19 samples were collected in the main production centers in the Región del Maule, <span class="hlt">Chile</span>. Samples were extracted with MeOH and assessed for antimicrobial activity against Gram (+) and Gram (-) bacteria. TP and TF content, antioxidant activity by the DPPH, FRAP and TEAC methods were also determined. Sample composition was assessed by HPLD-DAD-ESI-MS/MS. Differential compounds in the samples were isolated and characterized. The antimicrobial effect of the samples showed MICs ranging from 31.5 to > 1000 µg/mL. Propolis from the central valley was more effective as antibacterial than those from the coastal area or Andean slopes. The samples considered of interest (MIC ≤ 62.5 µg/mL) showed effect on Escherichia coli, Pseudomonas sp., Yersinia enterocolitica and Salmonella enteritidis. Two new diarylheptanoids, a diterpene, the flavonoids pinocembrin and chrysin were isolated and elucidated by spectroscopic and spectrometric means. Some 29 compounds were dereplicated by HPLC-MS and tentatively identified, including nine flavones/flavonol derivatives, one flavanone, eight dihydroflavonols and nine phenyl-propanoids. Propolis from the Región del Maule showed large variation in antimicrobial effect, antioxidant activity and composition. So far the presence of diarylheptanoids in samples from the coastal area of central <span class="hlt">Chile</span> can be considered as a marker of a new type of propolis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.V43B3148T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.V43B3148T"><span>Intense Seismic Activity at <span class="hlt">Chiles</span> and Cerro Negro Volcanoes on the Colombia-Ecuador Border</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Torres, R. A.; Cadena, O.; Gomez, D.; Ruiz, M. C.; Prejean, S. G.; Lyons, J. J.; White, R. A.</p> <p>2015-12-01</p> <p>The region of <span class="hlt">Chiles</span> and Cerro Negro volcanoes, located on the Colombian-Ecuadorian border, has experienced an ongoing seismic swarm beginning in Aug. 2013. Based on concern for local residents and authorities, a cooperative broadband monitoring network was installed by the Servicio Geológico Colombiano in Colombia and the Instituto Geofísico of the Escuela Politécnica Nacional in Ecuador. Since November 2013 more than 538,000 earthquakes were recorded; although since May 2015 the seismicity has decreased significantly to an average of 70 events per day. Three large earthquake swarms with increasing energy occurred in Aug.-Oct. 2013, March-May 2014, and Sept.-Dec. 2014. By the end of 2014, roughly 400 earthquakes greater than M 3 had occurred with a maximum rate of 8000 earthquakes per day. The largest earthquake was a 5.6 ML on Oct. 20, 2014. This event produced an InSAR coseismic deformation of ~23 cm (S. Ebmeier, personal communication). Most events are typical brittle failure volcano-tectonic (VT) earthquakes that are located in a cluster beneath the <span class="hlt">southern</span> flank of <span class="hlt">Chiles</span> volcano, with depths between 1.5 and 10 km. Although the great majority of earthquakes are VT, some low-frequency (LF, ~0.5 Hz) and very-low-frequency (VLF) events have occurred. Particle motion analysis suggests that the VLF source migrated with time. While a VLF on Oct. 15, 2014 was located south of <span class="hlt">Chiles</span> volcano, near the InSAR source, the VLF registered on Feb. 14, 2015 was likely located very close to <span class="hlt">Chiles</span> Volcano. We infer that magma intrusion and resulting fluid exsolution at depths greater than 5 km are driving seismicity in the <span class="hlt">Chiles</span>-Cerro Negro region. However earthquakes are failing in a manner consistent with regional tectonics. Relative relocations reveal a structure consistent with mapped regional faults. Thus seismicity is likely controlled by an interaction of magmatic and tectonic processes. Because the regional stress field is highly compressional and the volcanoes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.T34C..05S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.T34C..05S"><span>Could Fluid Seeps Originate from the Seismogenic <span class="hlt">Zone</span>? Evidence from <span class="hlt">Southern</span> Costa Rica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Silver, E. A.; Kluesner, J. W.; Nale, S. M.; Bangs, N. L.; McIntosh, K. D.; Ranero, C. R.; Tryon, M. D.; Spinelli, G. A.; Rathburn, T.; von Huene, R.</p> <p>2013-12-01</p> <p>The prevailing conceptual model of convergent margin hydrogeology is one in which fluid sourced from porosity loss and dehydration reactions seaward of the updip limit of the seismogenic <span class="hlt">zone</span> reach the seafloor via relatively low angle splay faults that act as high permeability conduits through an otherwise nearly impermeable upper plate [e.g., Lauer and Saffer, GRL, 39:L13604, 2012; Saffer and Tobin, Ann. Rev. Earth Planet. Sci., 39:157-186, 2011]. Interpretation of newly acquired 3D seismic reflection data and high resolvability multibeam and backscatter data, showing evidence for abundant potential fluid seeps sourced beneath the sediment cover and farther landward than previously thought possible, may require reevaluation of this concept. Kluesner et al. [2013, G3, doi:10.1002/ggge.20058], identified 160 potential fluid seeps in an 11 km wide swath off <span class="hlt">southern</span> Costa Rica, based on pockmarks and high backscatter mounds, each showing subsurface indicators of fluid migration in the seismic data. Approximately half of these potential seeps are on the outer continental shelf; these are landward of the updip limit of the seismogenic <span class="hlt">zone</span>, as estimated by both the transition from high to low reflectivity of the plate boundary and the intersection of the 150°C isotherm with the plate boundary [Ranero et al., 2008, G3, doi:10.1029/2007GC001679; Bangs et al., 2012, AGU Fall Meeting, T13A-2587; Bangs et al., this meeting]. We have mapped high probability fluid pathways beneath these potential seeps, based on seismic meta-attribute volumes calculated using user-trained neural network algorithms [Kluesner et al., this meeting]. The mapped fluid pathways are high-angle through the sedimentary section, and they root into basement highs and basement faults. Fluids could originate along the plate interface, where potential sources and pathways are known (Mid-slope sites: Hensen et al., 2004, Geology, 32:201-204), or above or below the interface, although sources from these</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22014675','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22014675"><span>Socioeconomic determinants of disability in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zitko Melo, Pedro; Cabieses Valdes, Báltica</p> <p>2011-10-01</p> <p>Disability is a worldwide public health priority. A shift from a biomedical perspective of dysfunction to a broader social understanding of disability has been proposed. Among many different social factors described in the past, socioeconomic position remains as a key multidimensional determinant of health. The study goal was to analyze the relationship between disability and different domains of socioeconomic position in <span class="hlt">Chile</span>. Cross-sectional analysis of an anonymized population-based survey conducted in <span class="hlt">Chile</span> in 2006. Any disability (dichotomous variable) and 6 different types of disability were analyzed on the bases of their relationship with income quintiles, occupational status, educational level, and material living standards (quality of the housing, overcrowding rate and sanitary conditions). Confounding and interaction effects were explored using R statistical program. Income, education, occupation, and material measures of socioeconomic position, along with some sociodemographic characteristics of the population, were independently associated with the chance of being disabled in <span class="hlt">Chile</span>. Interestingly, classic measures of socioeconomic position (income, education, and occupation) were consistently associated with any disability in <span class="hlt">Chile</span>, whereas material living conditions were partially confounded by these classic measures. In addition to this, each type of disability showed a particular pattern of related social determinants, which also varied by age group. This study contributed to the understanding of disability in <span class="hlt">Chile</span> and how different domains of socioeconomic position might be associated with this prevalent condition. Disability remains a complex multidimensional public health problem in <span class="hlt">Chile</span> that requires the inclusion of a wide range of risk factors, of which socioeconomic position is particularly relevant. Copyright © 2011 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25137143','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25137143"><span>Lactase persistence and dairy intake in Mapuche and Mestizo populations from <span class="hlt">southern</span> <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fernández, Catalina I; Flores, Sergio V</p> <p>2014-11-01</p> <p>Lactase persistence (LP) occurs at a very low frequency in indigenous populations from Latin America, offering an opportunity to understand the relationship between this genetic trait and patterns of dairy consumption. Here, the frequency of LP is analyzed from Mapuche and -an adjacent- mestizo population inhabiting the Araucanía region. In addition to genotyping for LP, participants were surveyed in relation to general perception and consumption habits of dairy products. Low LP frequency (10%) and very low dairy intake was found among the Mapuche population as compared with Mestizo populations inhabiting <span class="hlt">Chile</span>. The survey reported that the main reasons for avoidance of dairy were the gastrointestinal symptoms after dairy intake and cultural dietary habits. The interaction between low LP genotype frequency, low dairy intake, and sociocultural determinants is here discussed in the light of their potential health outcomes. © 2014 Wiley Periodicals, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26699612','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26699612"><span>Photosynthetic Light Responses May Explain Vertical Distribution of Hymenophyllaceae Species in a Temperate Rainforest of <span class="hlt">Southern</span> <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Parra, María José; Acuña, Karina I; Sierra-Almeida, Angela; Sanfuentes, Camila; Saldaña, Alfredo; Corcuera, Luis J; Bravo, León A</p> <p>2015-01-01</p> <p>Some epiphytic Hymenophyllaceae are restricted to lower parts of the host (< 60 cm; 10-100 μmol photons m(-2) s(-1)) in a secondary forest of <span class="hlt">Southern</span> <span class="hlt">Chile</span>; other species occupy the whole host height (≥ 10 m; max PPFD > 1000 μmol photons m(-2) s(-1)). Our aim was to study the photosynthetic light responses of two Hymenophyllaceae species in relation to their contrasting distribution. We determined light tolerance of Hymenoglossum cruentum and Hymenophyllum dentatum by measuring gas exchange, PSI and PSII light energy partitioning, NPQ components, and pigment contents. H. dentatum showed lower maximum photosynthesis rates (A max) than H. cruentum, but the former species kept its net rates (An) near Amax across a wide light range. In contrast, in the latter one, An declined at PPFDs > 60 μmol photons m(-2) s(-1). H. cruentum, the shadiest plant, showed higher chlorophyll contents than H. dentatum. Differences in energy partitioning at PSI and PSII were consistent with gas exchange results. H. dentatum exhibited a higher light compensation point of the partitioning of absorbed energy between photochemical Y(PSII) and non-photochemical Y(NPQ) processes. Hence, both species allocated energy mainly toward photochemistry instead of heat dissipation at their light saturation points. Above saturation, H. cruentum had higher heat dissipation than H. dentatum. PSI yield (YPSI) remained higher in H. dentatum than H. cruentum in a wider light range. In both species, the main cause of heat dissipation at PSI was a donor side limitation. An early dynamic photo-inhibition of PSII may have caused an over reduction of the Qa+ pool decreasing the efficiency of electron donation to PSI. In H. dentatum, a slight increase in heat dissipation due to acceptor side limitation of PSI was observed above 300 μmol photons m(-2)s(-1). Differences in photosynthetic responses to light suggest that light tolerance and species plasticity could explain their contrasting vertical distribution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S13D4519Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S13D4519Y"><span>Spatial Distribution of earthquakes off the coast of Fukushima Two Years after the M9 Earthquake: the <span class="hlt">Southern</span> Area of the 2011 Tohoku Earthquake Rupture <span class="hlt">Zone</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamada, T.; Nakahigashi, K.; Shinohara, M.; Mochizuki, K.; Shiobara, H.</p> <p>2014-12-01</p> <p>Huge earthquakes cause vastly stress field change around the rupture <span class="hlt">zones</span>, and many aftershocks and other related geophysical phenomenon such as geodetic movements have been observed. It is important to figure out the time-spacious distribution during the relaxation process for understanding the giant earthquake cycle. In this study, we pick up the <span class="hlt">southern</span> rupture area of the 2011 Tohoku earthquake (M9.0). The seismicity rate keeps still high compared with that before the 2011 earthquake. Many studies using ocean bottom seismometers (OBSs) have been doing since soon after the 2011 Tohoku earthquake in order to obtain aftershock activity precisely. Here we show one of the studies at off the coast of Fukushima which is located on the <span class="hlt">southern</span> part of the rupture area caused by the 2011 Tohoku earthquake. We deployed 4 broadband type OBSs (BBOBSs) and 12 short-period type OBSs (SOBS) in August 2012. Other 4 BBOBSs attached with absolute pressure gauges and 20 SOBSs were added in November 2012. We recovered 36 OBSs including 8 BBOBSs in November 2013. We selected 1,000 events in the vicinity of the OBS network based on a hypocenter catalog published by the Japan Meteorological Agency, and extracted the data after time corrections caused by each internal clock. Each P and S wave arrival times, P wave polarity and maximum amplitude were picked manually on a computer display. We assumed one dimensional velocity structure based on the result from an active source experiment across our network, and applied time corrections every station for removing ambiguity of the assumed structure. Then we adopted a maximum-likelihood estimation technique and calculated the hypocenters. The results show that intensive activity near the Japan Trench can be seen, while there was a quiet seismic <span class="hlt">zone</span> between the trench <span class="hlt">zone</span> and landward high activity <span class="hlt">zone</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26436791','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26436791"><span>[Beginning of the Microbiology education in <span class="hlt">Chile</span>: formation centers].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Osorio, Carlos</p> <p>2015-08-01</p> <p>The first Chair of Microbiology in <span class="hlt">Chile</span> was created in the School of Medicine of the Cañadilla at the University of <span class="hlt">Chile</span> in 1892. Dr. Alejandro del Río Soto Aguilar was its first Professor. For almost three decades it was the only educational center for microbiologists in <span class="hlt">Chile</span>. Among them were the first Professors of the new School of Medicine of the Catholic University of <span class="hlt">Chile</span> and of the University of Concepción.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title33-vol1/pdf/CFR-2011-title33-vol1-sec3-05-30.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title33-vol1/pdf/CFR-2011-title33-vol1-sec3-05-30.pdf"><span>33 CFR 3.05-30 - Sector New York Marine Inspection <span class="hlt">Zone</span> and Captain of the Port <span class="hlt">Zone</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-07-01</p> <p>..., longitude 73°40′00″ W; thence south to a point near the <span class="hlt">southern</span> shore of Manursing Island at latitude 40°58... Sector New York's Marine Inspection <span class="hlt">Zone</span> and Captain of the Port <span class="hlt">Zone</span> start near the south shore of Long Island at latitude 40°35′24″ N, longitude 73°46′36″ W proceeding southeast to a point at latitude 38°28...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29475674','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29475674"><span>Environmental radiation and potential ecological risk levels in the intertidal <span class="hlt">zone</span> of <span class="hlt">southern</span> region of Tamil Nadu coast (HBRAs), India.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Punniyakotti, J; Ponnusamy, V</p> <p>2018-02-01</p> <p>Natural radioactivity content and heavy metal concentration in the intertidal <span class="hlt">zone</span> sand samples from the <span class="hlt">southern</span> region of Tamil Nadu coast, India, have been analyzed using gamma ray spectrometer and ICP-OES, respectively. From gamma spectral analysis, the average radioactivity contents of 238 U, 232 Th, and 40 K in the intertidal <span class="hlt">zone</span> sand samples are 12.13±4.21, 59.03±4.26, and 197.03±26.24Bq/kg, respectively. The average radioactivity content of 232 Th alone is higher than the world average value. From the heavy metal analysis, the average Cd, Cr, Cu, Ni, Pb, and Zn concentrations are 3.1, 80.24, 82.84, 23.66, 91.67, and 137.07ppm, respectively. The average Cr and Ni concentrations are lower, whereas other four metal (Cd, Cu, Pb, and Zn) concentrations are higher than world surface rock average values. From pollution assessment parameter values, the pollution level is "uncontaminated to moderately contaminated" in the study area. Copyright © 2017 Elsevier Ltd. All rights reserved.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018DokES.479..463P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018DokES.479..463P"><span>Ankaramite: A New Type of High-Magnesium and High-Calcium Primitive Melt in the Magnitogorsk Island-Arc <span class="hlt">Zone</span> (<span class="hlt">Southern</span> Urals)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pushkarev, E. V.; Ryazancev, A. V.; Gottman, I. A.; Degtyarev, K. E.; Kamenetsky, V. S.</p> <p>2018-04-01</p> <p>This work describes the geological position, mineral and chemical composition of high-Mg effusive ankaramites occurring as dykes and lava flows. They were found in the mélange <span class="hlt">zone</span> of the western margin of the Magnitogorsk island arc <span class="hlt">zone</span> in the <span class="hlt">Southern</span> Urals. Data on the liquidus association of phenocrysts and on the composition of the matrix of effusives are given. According to the data obtained, the conclusion was drawn that the ankaramites studied can be attributed to the primary island arc melts, which were not subject to essential differentiation. This type of effusives has not been distinguished previously among island arc volcanogenic formations of the Urals. It is shown that ankaramites can be considered to be primary melts parental for dunite-clinopyroxenites-gabbro complexes of Ural-Alaskan type. The occurrence of ankaramites in the Paleozoic island arc formations of the Urals indicates the wehrlite composition of the mantle as the reason for the extremely wide development of wehrlites and clinopyroxenites in different mafic-ultramafic complexes of the Urals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.T43H..04C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.T43H..04C"><span>Subduction <span class="hlt">Zone</span> Dewatering at the <span class="hlt">Southern</span> End of New Zealand's Hikurangi Margin - Insights from 2D Seismic Tomography</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Crutchley, G. J.; Klaeschen, D.</p> <p>2016-12-01</p> <p>The <span class="hlt">southern</span> end of New Zealand's Hikurangi subduction margin is characterised by highly-oblique convergence as it makes a southward transition into a right-lateral transform plate boundary. Long-offset seismic data that cross part of the offshore portion of this transition <span class="hlt">zone</span> give new insight into the nature of the margin. We have carried out two-dimensional pre-stack depth migrations with an iterative reflection tomography to update the velocity field on two seismic lines in this area. The depth-migrated sections show much-improved imaging of faulting within the wedge, and the seismic velocities themselves give clues about the distribution of gas and/or overpressured regions at the plate boundary and within the overlying wedge. A fascinating observation is a major splay fault that has been (or continues to be) a preferred dewatering pathway through the wedge, evidenced by a thermal anomaly that has left its mark on the overlying gas hydrate layer. Another interesting observation is a thick and laterally extensive low velocity <span class="hlt">zone</span> beneath the subduction interface, which might have important implications for the long-term mechanical stability of the interface. Our on-going work on these data is focused on amplitude versus offset analysis in an attempt to better understand the nature of the subduction interface and also the shallower gas hydrate system. This study is an example of how distinct disturbances of the gas hydrate system can provide insight into subduction <span class="hlt">zone</span> fluid flow processes that are important for understanding wedge stability and ultimately earthquake hazard.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988HM.....42..469M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988HM.....42..469M"><span>Studies on sexual compatibility between Ectocarpus siliculosus (Phaeophyceae) from <span class="hlt">Chile</span> and the Mediterranean Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Müller, Dieter G.</p> <p>1988-09-01</p> <p>Clonal isolates of the brown alga Ectocarpus siliculosus (Ectocarpales) originating from Naples (Mediterranean Sea) and <span class="hlt">southern</span> <span class="hlt">Chile</span> were compared in laboratory culture studies. The two isolates showed distinctly different morphological characters, but very similar details of life history and sexual reproduction. Gametes are sexually compatible; hybrid zygotes are formed and sporophytes develop, which are fertile on the basis of mitotic spores. However, unilocular sporangia were abortive, indicating segregational sterility caused by chromosomal mismatch during meiosis. Although the biological species concept in a strict sense does not apply, and appreciable morphological variability exists in this cosmopolitan taxon, local populations are considered as representatives of the same species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70015418','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70015418"><span>Enrichment of trace elements in garnet amphibolites from a paleo-subduction <span class="hlt">zone</span>: Catalina Schist, <span class="hlt">southern</span> California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Sorensen, Sorena S.; Grossman, J.N.</p> <p>1989-01-01</p> <p>The abundance, P-T stability, solubility, and element-partitioning behavior of minerals such as rutile, garnet, sphene, apatite, zircon, zoisite, and allanite are critical variables in models for mass transfer from the slab to the mantle wedge in deep regions of subduction <span class="hlt">zones</span>. The influence of these minerals on the composition of subduction-related magmas has been inferred (and disputed) from inverse modelling of the geochemistry of island-arc basalt, or by experiment. Although direct samples of the dehydration + partial-melting region of a mature subduction <span class="hlt">zone</span> have not been reported from subduction complexes, garnet amphibolites from melanges of circumpacific and Caribbean blueschist terranes reflect high T (>600??C) conditions in shallower regions. Such rocks record geochemical processes that affected deep-seated, high-T portions of paleo-subduction <span class="hlt">zones</span>. In the Catalina Schist, a subduction-<span class="hlt">zone</span> metamorphic terrane of <span class="hlt">southern</span> California, metasomatized and migmatitic garnet amphibolites occur as blocks in a matrix of meta-ultramafic rocks. This mafic and ultramafic complex may represent either slab-derived material accreted to the mantle wedge of a nascent subduction <span class="hlt">zone</span> or a portion of a shear <span class="hlt">zone</span> closely related to the slab-mantle wedge contact, or both. The trace-element geochemistry of the complex and the distribution of trace elements among the minerals of garnet amphibolites were studied by INAA, XRF, electron microprobe, and SEM. In order of increasing alteration from a probable metabasalt protolith, three common types of garnet amphibolite blocks in the Catalina Schist are: (1) non-migmatitic, clinopyroxene-bearing blocks, which are compositionally similar to MORB that has lost an albite component; (2) garnet-amphibolite blocks, which have rinds that reflect local interaction between metabasite, metaperidotite, and fluid; and (3) migmatites that are extremely enriched in Th, HFSE, LREE, and other trace elements. These trace-element enrichments</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2013-06-12/pdf/2013-13946.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2013-06-12/pdf/2013-13946.pdf"><span>78 FR 35103 - Extension of Border <span class="hlt">Zone</span> in the State of New Mexico</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2013-06-12</p> <p>... Record. This change is intended to promote commerce and tourism in <span class="hlt">southern</span> New Mexico while still... border <span class="hlt">zone</span>. In order to facilitate commerce, trade, and tourism in <span class="hlt">southern</span> New Mexico, while still..., trade, and tourism in <span class="hlt">southern</span> New Mexico, while still ensuring that sufficient safeguards are in place...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGeo..117...75Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGeo..117...75Y"><span>Estimates of effective elastic thickness at subduction <span class="hlt">zones</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, An; Fu, Yongtao</p> <p>2018-06-01</p> <p>The effective elastic thickness (Te) is an important parameter that characterizes the long-term strength of the lithosphere. Estimates of Te at subduction <span class="hlt">zones</span> have important tectonic and geodynamic implications, providing constraints for the strength of the oceanic lithosphere at a short-term scale. We estimated Te values in several subduction <span class="hlt">zones</span> worldwide by using models including both surface and subsurface loads from the analysis of free-air gravity anomaly and bathymetric data, together with a moving window admittance technique (MWAT). Tests with synthetic gravity and bathymetry data show that this method is a reliable way to recover Te of oceanic lithosphere. Our results show that there is a noticeable reduction in the effective elastic thickness of the subducting plate from the outer rise to the trench axis for most studied subduction <span class="hlt">zones</span>, suggesting plate weakening at the trench-outer rise of the subduction <span class="hlt">zones</span>. These subduction <span class="hlt">zones</span> have Te range of 6-60 km, corresponding to a wide range of isotherms from 200 to 800 °C. Different trenches show distinct patterns. The Caribbean, Kuril-Japan, Mariana and Tonga subduction <span class="hlt">zones</span> show predominantly high Te. By contrast, the Middle America and Java subduction <span class="hlt">zones</span> have a much lower Te. The Peru-<span class="hlt">Chile</span>, Aleutian and Philippine subduction <span class="hlt">zones</span> show considerable scatter. The large variation of the isotherm for different trenches does not show clear relationship with plate weakening at the outer rise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70155221','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70155221"><span>Fine-scale movements of rural free-ranging dogs in conservation areas in the temperate rainforest of the coastal range of <span class="hlt">southern</span> <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Sepulveda, Maximiliano; Pelican, Katherine; Cross, Paul C.; Eguren, Antonieta; Singer, Randall S.</p> <p>2015-01-01</p> <p>Domestic dogs can play a variety of important roles for farmers. However, when in proximity to conservation areas, the presence of rural free-ranging dogs can be problematic due to the potential for predation of, competition with, or transmission of infectious disease to local threatened fauna. We used a frequent location radio tracking technology to study rural free-ranging dog movements and habitat use into sensitive conservation habitats. To achieve a better understanding of foray behaviors in dogs we monitored dogs (n = 14) in rural households located in an isolated area between the Valdivian Coastal Reserve and the Alerce Costero National Park in <span class="hlt">southern</span> <span class="hlt">Chile</span>. Dogs were mostly located near households (<200 m) but exhibited a diurnal pattern of directed excursions (forays) away from their home locations. Dogs spent, on average, 5.3% of their time in forays with average per dog foray distances from the house ranging 0.5–1.9 km (maximum distance detected 4.3 km). Foraying behavior was positively associated with pasture habitat compared to forest habitat including protected lands. Foraying dogs rarely used forest habitat and, when entered, trails and/or roads were selected for movement. Our study provides important information about how dogs interact in a fine-scale with wildlife habitat, and, in particular, protected lands, providing insight into how dog behavior might drive wildlife interactions, and, in turn, how an understanding of dog behavior can be used to manage these interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pages.unibas.ch/earth/tecto/Members/Kounov/Downloads/van_der_Lelij_et_al_2010_(Tectonics).pdf','USGSPUBS'); return false;" href="http://pages.unibas.ch/earth/tecto/Members/Kounov/Downloads/van_der_Lelij_et_al_2010_(Tectonics).pdf"><span>Thermochronology and tectonics of the Leeward Antilles: Evolution of the <span class="hlt">southern</span> Caribbean Plate boundary <span class="hlt">zone</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>van der Lelij, Roelant; Spikings, Richard A.; Kerr, Andrew C.; Kounov, Alexandre; Cosca, Michael; Chew, David; Villagomez, Diego</p> <p>2010-01-01</p> <p>Tectonic reconstructions of the Caribbean Plate are severely hampered by a paucity of geochronologic and exhumation constraints from anastomosed basement blocks along its <span class="hlt">southern</span> margin. New U/Pb, 40Ar/39Ar, apatite fission track, and apatite (U-Th)/He data constrain quantitative thermal and exhumation histories, which have been used to propose a model for the tectonic evolution of the emergent parts of the Bonaire Block and the <span class="hlt">southern</span> Caribbean Plate boundary <span class="hlt">zone</span>. An east facing arc system intruded through an oceanic plateau during ~90 to ~87 Ma and crops out on Aruba. Subsequent structural displacements resulted in >80°C of cooling on Aruba during 70–60 Ma. In contrast, exhumation of the island arc sequence exposed on Bonaire occurred at 85–80 Ma and 55–45 Ma. Santonian exhumation on Bonaire occurred immediately subsequent to burial metamorphism and may have been driven by the collision of a west facing island arc with the Caribbean Plate. Island arc rocks intruded oceanic plateau rocks on Gran Roque at ~65 Ma and exhumed rapidly at 55–45 Ma. We attribute Maastrichtian-Danian exhumation on Aruba and early Eocene exhumation on Bonaire and Gran Roque to sequential diachronous accretion of their basement units to the South American Plate. Widespread unconformities indicate late Eocene subaerial exposure. Late Oligocene–early Miocene dextral transtension within the Bonaire Block drove subsidence and burial of crystalline basement rocks of the Leeward Antilles to ≤1 km. Late Miocene–recent transpression caused inversion and ≤1 km of exhumation, possibly as a result of the northward escape of the Maracaibo Block.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.8573G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.8573G"><span>Late Holocene megathrust earthquakes in south central <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Garrett, Ed; Shennan, Ian; Gulliver, Pauline; Woodroffe, Sarah</p> <p>2013-04-01</p> <p>A lack of comprehensive understanding of the seismic hazards associated with a subduction <span class="hlt">zone</span> can lead to inadequate anticipation of earthquake and tsunami magnitudes. Four hundred and fifty years of Chilean historical documents record the effects of numerous great earthquakes; however, with recurrence intervals between the largest megathrust earthquakes approaching 300 years, seismic hazard assessment requires longer chronologies. This research seeks to verify and extend historical records in south central <span class="hlt">Chile</span> using a relative-sea level approach to palaeoseismology. Our quantitative, diatom-based approaches to relative sea-level reconstruction are successful in reconstructing the magnitude of coseismic deformation during recent, well documented Chilean earthquakes. The few disparities between my estimates and independent data highlight the possibility of shaking-induced sediment consolidation in tidal marshes. Following this encouraging confirmation of the approach, we quantify land-level changes in longer sedimentary records from the centre of the rupture <span class="hlt">zone</span> of the 1960 Valdivia earthquake. Here, laterally extensive marsh soils abruptly overlain by low intertidal sediments attest to the occurrence of four megathrust earthquakes. Sites preserve evidence of the 1960 and 1575 earthquakes and we constrain the timing of two predecessors to 1270 to 1410 and 1050 to 1200. The sediments and biostratigraphy lack evidence for the historically documented 1737 and 1837 earthquakes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/15744','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/15744"><span>Soil water nitrate concentrations in giant cane and forest riparian buffer <span class="hlt">zones</span></span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Jon E. Schoonover; Karl W. J. Williard; James J. Zaczek; Jean C. Mangun; Andrew D. Carver</p> <p>2003-01-01</p> <p>Soil water nitrate concentrations in giant cane and forest riparian buffer <span class="hlt">zones</span> along Cypress Creek in <span class="hlt">southern</span> Illinois were compared to determine if the riparian <span class="hlt">zones</span> were sources or sinks for nitrogen in the rooting <span class="hlt">zone</span>. Suction lysimeters were used to collect soil water samples from the lower rooting <span class="hlt">zone</span> in each of the two vegetation types. The cane riparian...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EurSS..49..326S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EurSS..49..326S"><span>Composition and structure of aggregates from compacted soil horizons in the <span class="hlt">southern</span> steppe <span class="hlt">zone</span> of European Russia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sorokin, A. S.; Abrosimov, K. N.; Lebedeva, M. P.; Kust, G. S.</p> <p>2016-03-01</p> <p>The composition and structure of aggregates from different agrogenic soils in the <span class="hlt">southern</span> steppe <span class="hlt">zone</span> of European Russia have been studied. It is shown that the multi-level study (from the macro- to microlevel) of these horizons makes it possible to identify soil compaction caused by different elementary soil processes: solonetz-forming, vertisol-forming, and mechanical (wheel) compaction in the rainfed and irrigated soils. The understanding of the genesis of the compaction of soil horizons (natural or anthropogenic) is important for the economic evaluation of soil degradation. It should enable us to make more exact predictions of the rates of degradation processes and undertake adequate mitigation measures. The combined tomographic and micromorphological studies of aggregates of 1-2 and 3-5 mm in diameter from compacted horizons of different soils have been performed for the first time. Additional diagnostic features of negative solonetz- forming processes (low open porosity of aggregates seen on tomograms and filling of a considerable part of the intraped pores with mobile substance) and the vertisol-forming processes (large amount of fine intraaggregate pores seen on tomograms and a virtual absence of humus-clay plasma in the intraped <span class="hlt">zone</span>)—have been identified. It is shown that the combination of microtomographic and micromorphological methods is helpful for studying the pore space of compacted horizons in cultivated soils.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4511626','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4511626"><span>Transport accidents among children and adolescents at the emergency service of a teaching hospital in the <span class="hlt">southern</span> <span class="hlt">zone</span> of the city of São Paulo☆☆☆</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gorios, Carlos; de Souza, Renata Maia; Gerolla, Viviane; Maso, Bruno; Rodrigues, Cintia Leci; Armond, Jane de Eston</p> <p>2014-01-01</p> <p>Objective to describe the victim profile and circumstances of transport accidents involving children and adolescents who were attended at a teaching hospital in the <span class="hlt">southern</span> <span class="hlt">zone</span> of the city of São Paulo. Methods this was an individual observational case series study among patients up to the age of 19 years who were attended at a hospital in the <span class="hlt">southern</span> <span class="hlt">zone</span> of the city of São Paulo, state of São Paulo, Brazil, due to traffic accidents. The files notifying suspected or confirmed cases of violence and accidents (SIVVA files) covering January to December 2012 were analyzed. Results among the 149 cases notified, 64.4% related to males and 35.6% to females. The transport accidents were predominantly among males, irrespective of age. The main injury diagnoses were superficial head trauma (24.8%) followed by multiple non-specified trauma (36.4%), in both sexes. Conclusion transport accidents among children and adolescents occurred more often among males. The main transport accidents among the children and adolescents attended as emergency cases were caused by motor vehicles and motorcycles. Among the accident victims, the largest proportion was attended because of being run over. PMID:26229833</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4088115','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4088115"><span>Human papillomavirus in esophageal squamous cell carcinoma in Colombia and <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Castillo, Andres; Aguayo, Francisco; Koriyama, Chihaya; Torres, Miyerlandi; Carrascal, Edwin; Corvalan, Alejandro; Roblero, Juan P; Naquira, Cecilia; Palma, Mariana; Backhouse, Claudia; Argandona, Jorge; Itoh, Tetsuhiko; Shuyama, Karem; Eizuru, Yoshito; Akiba, Suminori</p> <p>2006-01-01</p> <p>AIM: To examine the presence of human papillomavirus (HPV) in esophageal squamous cell carcinoma (ESCC) specimens collected from Colombia and <span class="hlt">Chile</span> located in the northern and <span class="hlt">southern</span> ends of the continent, respectively. METHODS: We examined 47 and 26 formalin-fixed and paraffin-embedded ESCC specimens from Colombia and <span class="hlt">Chile</span>, respectively. HPV was detected using GP5+/GP6+ primer pair for PCR, and confirmed by <span class="hlt">Southern</span> blot analysis. Sequencing analysis of L1 region fragment was used to identify HPV genotype. In addition, P16INK4A protein immunostaining of all the specimens was conducted. RESULTS: HPV was detected in 21 ESCC specimens (29%). Sequencing analysis of L1 region fragment identified HPV-16 genome in 6 Colombian cases (13%) and in 5 Chilean cases (19%). HPV-18 was detected in 10 cases (21%) in Colombia but not in any Chilean case. Since Chilean ESCC cases had a higher prevalence of HPV-16 (without statistical significance), but a significantly lower prevalence of HPV-18 than in Colombian cases (P = 0.011) even though the two countries have similar ESCC incidence rates, the frequency of HPV-related ESCC may not be strongly affected by risk factors affecting the incidence of ESCC. HPV-16 genome was more frequently detected in p16 positive carcinomas, although the difference was not statistically significant. HPV-18 detection rate did not show any association with p16 expression. Well-differentiated tumors tended to have either HPV-16 or HPV-18 but the association was not statistically significant. HPV genotypes other than HPV-16 or 18 were not detected in either country. CONCLUSION: HPV-16 and HPV-18 genotypes can be found in ESCC specimens collected from two South American countries. Further studies on the relationship between HPV-16 presence and p16 expression in ESCC would aid understanding of the mechanism underlying the presence of HPV in ESCC. PMID:17036393</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21752410','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21752410"><span>Characterization of backyard poultry production systems and disease risk in the central <span class="hlt">zone</span> of <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hamilton-West, C; Rojas, H; Pinto, J; Orozco, J; Hervé-Claude, L P; Urcelay, S</p> <p>2012-08-01</p> <p>Backyard poultry production systems (BPS) are an important and widespread form of poultry production. There is a common perception that biosecurity standards in BPS are generally poor and BPS are usually associated with animal diseases and zoonoses. In this study BPS were identified in the vicinity of six wetlands, having these a higher risk of presenting and introducing avian diseases such as HPAI and Newcastle disease, as defined by the national veterinary services, in to <span class="hlt">Chile</span>'s main poultry production area. BPS were characterized through a field questionnaire and the main areas covered by the survey were BPS structure, biosecurity and value chain. The BPS identified in this study share most characteristics on biosecurity, poultry management and product commercialization, but it was possible to identify a certain degree of variation within and among the study sites. BPS in <span class="hlt">Chile</span> are similar to those in other regions, with a relatively small flock size (average 37 birds), a low level of biosecurity measures and lack of poultry disease management. Management findings include that most farmers used mixed/partial confinement, with low or no biosecurity and disease control measures in place. Eggs were the main output and were used mainly for home consumption or sale at local markets. Sick birds' treatment with drugs approved for other species or for human use could represent a risk to human health, owing to the possible presence of drug residues in poultry products. Despite the different structures of the poultry sector worldwide, BPS can play a major role in disease maintenance and spread because its management conditions characteristics and the lack of animal health services adapted to these production systems. This should be an alert message to the veterinary authorities to improve coverage of veterinary assistance and surveillance activities in backyard poultry production. Copyright © 2011 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4193174','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4193174"><span>Person-to-Person Household and Nosocomial Transmission of Andes Hantavirus, <span class="hlt">Southern</span> <span class="hlt">Chile</span>, 2011</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Martinez-Valdebenito, Constanza; Calvo, Mario; Vial, Cecilia; Mansilla, Rita; Marco, Claudia; Palma, R. Eduardo; Vial, Pablo A.; Valdivieso, Francisca; Mertz, Gregory</p> <p>2014-01-01</p> <p>Andes hantavirus (ANDV) causes hantavirus cardiopulmonary syndrome in <span class="hlt">Chile</span> and is the only hantavirus for which person-to-person transmission has been proven. We describe an outbreak of 5 human cases of ANDV infection in which symptoms developed in 2 household contacts and 2 health care workers after exposure to the index case-patient. Results of an epidemiologic investigation and sequence analysis of the virus isolates support person-to-person transmission of ANDV for the 4 secondary case-patients, including nosocomial transmission for the 2 health care workers. Health care personnel who have direct contact with ANDV case-patients or their body fluids should take precautions to prevent transmission of the virus. In addition, because the incubation period of ANDV after environmental exposure is longer than that for person-to-person exposure, all persons exposed to a confirmed ANDV case-patient or with possible environmental exposure to the virus should be monitored for 42 days for clinical symptoms. PMID:25272189</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011BVol...73..223W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011BVol...73..223W"><span>Ash storms: impacts of wind-remobilised volcanic ash on rural communities and agriculture following the 1991 Hudson eruption, <span class="hlt">southern</span> Patagonia, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilson, T. M.; Cole, J. W.; Stewart, C.; Cronin, S. J.; Johnston, D. M.</p> <p>2011-04-01</p> <p>Tephra fall from the August 1991 eruption of Volcán Hudson affected some 100,000 km2 of Patagonia and was almost immediately reworked by strong winds, creating billowing clouds of remobilised ash, or `ash storms'. The immediate impacts on agriculture and rural communities were severe, but were then greatly exacerbated by continuing ash storms. This paper describes the findings of a 3-week study tour of the diverse environments of <span class="hlt">southern</span> Patagonia affected by ash storms, with an emphasis on determining the impacts of repeated ash storms on agriculture and local practices that were developed in an attempt to mitigate these impacts. Ash storms produce similar effects to initial tephra eruptions, prolonged for considerable periods. These have included the burial of farmland under dune deposits, abrasion of vegetation and contamination of feed supplies with fine ash. These impacts can then cause problems for grazing animals such as starvation, severe tooth abrasion, gastrointestinal problems, corneal abrasion and blindness, and exhaustion if sheep fleeces become laden with ash. In addition, ash storms have led to exacerbated soil erosion, human health impacts, increased cleanup requirements, sedimentation in irrigation canals, and disruption of aviation and land transport. Ash deposits were naturally stabilised most rapidly in areas with high rainfall (>1,500 mm/year) through compaction and enhanced vegetation growth. Stabilisation was slowest in windy, semi-arid regions. Destruction of vegetation and suppression of regrowth by heavy tephra fall (>100 mm) hindered the stabilisation of deposits for years, and reduced the surface friction which increased wind erosivity. Stabilisation of tephra deposits was improved by intensive tillage, use of windbreaks and where there was dense and taller vegetative cover. Long-term drought and the impracticality of mixing ash deposits with soil by tillage on large farms was a barrier to stabilising deposits and, in turn</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5221643','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5221643"><span>The current situation for gastric cancer in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Caglevic, Christian; Silva, Shirley; Mahave, Mauricio; Rolfo, Christian; Gallardo, Jorge</p> <p>2016-01-01</p> <p>Gastric cancer is a neoplasm with a high incidence and mortality rate in <span class="hlt">Chile</span> where more than 3000 people die every year from this type of cancer. This study shows the clinical and epidemiological considerations of this disease, information about translational research on this pathology in <span class="hlt">Chile</span>, the contribution of Chilean doctors to the development of gastric cancer management awareness and the general situation of gastric cancer in <span class="hlt">Chile</span>. PMID:28105078</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28105078','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28105078"><span>The current situation for gastric cancer in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Caglevic, Christian; Silva, Shirley; Mahave, Mauricio; Rolfo, Christian; Gallardo, Jorge</p> <p>2016-01-01</p> <p>Gastric cancer is a neoplasm with a high incidence and mortality rate in <span class="hlt">Chile</span> where more than 3000 people die every year from this type of cancer. This study shows the clinical and epidemiological considerations of this disease, information about translational research on this pathology in <span class="hlt">Chile</span>, the contribution of Chilean doctors to the development of gastric cancer management awareness and the general situation of gastric cancer in <span class="hlt">Chile</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=2013%2c+AND+Brazil&id=EJ1027928','ERIC'); return false;" href="https://eric.ed.gov/?q=2013%2c+AND+Brazil&id=EJ1027928"><span>Rising Expectations in Brazil and <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Elacqua, Gregory; Alves, Fatima</p> <p>2014-01-01</p> <p>Two themes connect Brazil and <span class="hlt">Chile</span>: one is economic success; the other is social unrest. Protests rocked cities across Brazil in June 2013, and in <span class="hlt">Chile</span>, recent student protests turned violent. Yet living conditions in both nations are better now than they've ever been. Successful economic and social reforms over the last two decades have led to…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012BGD.....9.3423P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012BGD.....9.3423P"><span>Late summer particulate organic carbon export and twilight <span class="hlt">zone</span> remineralisation in the Atlantic sector of the <span class="hlt">Southern</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Planchon, F.; Cavagna, A.-J.; Cardinal, D.; André, L.; Dehairs, F.</p> <p>2012-03-01</p> <p>During the Bonus-GoodHope (BGH) expedition (Jan-Mar 2008) we studied the water column distribution of total 234Th and biogenic particulate Ba (Baxs) in the Atlantic sector of the <span class="hlt">Southern</span> Ocean. The objective was to assess the export flux of particulate organic carbon (POC) from the surface to the mesopelagic twilight <span class="hlt">zone</span> along a section between the Cape Basin and Weddell Gyre. Export production of POC was estimated from steady state and non steady state export fluxes of 234Th which were converted into POC fluxes, using the POC/234Th ratio of large (>53 μm) suspended particles, collected via in-situ pumps. Deficits in 234Th activities were observed at all stations from the surface to the bottom of the mixed-layer. 234Th export fluxes from the upper 100 m ranged from 496 ± 57 dpm m-2 d-1 to 1195 ± 120 dpm m-2 d-1 for the steady state model and from 149 ± 18 dpm m-2 d-1 to 1217 ± 146 dpm m-2 d-1 for the non steady state model calculated for a time window of 15 to 22 days preceding the timing of the present cruise. The POC/234Thp ratio of large, potentially sinking particles (>53 μm), was observed to increase with latitude, from 1.9 ± 0.2 μmol dpm-1 and 1.7 ± 0.3 μmol dpm-1 in the Subtropical <span class="hlt">Zone</span> (STZ) and Subantarctic <span class="hlt">Zone</span> (SAZ), respectively, to 3.0 ± 0.2 μmol dpm-1 in the Polar Front <span class="hlt">Zone</span> (PFZ), 4.8 ± 1.9 μmol dpm-1 at the <span class="hlt">Southern</span> Antarctic Circumpolar Current Front (SACCF) to 4.1 ± 1.7 μmol dpm-1 in the northern Weddell Gyre, in line with an increasing contribution of larger cell diatoms. Steady state and non steady state POC export from the upper 100 m ranged from 0.9 ± 0.2 mmolC m-2 d-1 to 5.1 ± 2.1 mmolC m-2 d-1 and from 0.3 ± 0.0 mmolC m-2 d-1 to 4.9 ± 3.2 mmolC m-2 d-1, respectively. From the SAZ to the SACCF, non steady state POC export production represented only 15 to 54 % of the steady state POC flux, suggesting that the intensity of export had decreased over time partly due to the fact that regenerated-production based communities</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1914972Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1914972Z"><span>Co-evolution of land use changes, water quality deterioration and social conflicts in arid Northern <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zang, Carina; Dame, Juliane</p> <p>2017-04-01</p> <p>Water scarcity concerns not only the limited availability of water but also water of inadequate quality in terms of its designated purposes. Arid regions, such as found in Northern <span class="hlt">Chile</span>, are especially vulnerable to water contamination, owing to missing dilution. Additionally, the national government of <span class="hlt">Chile</span>'s goal to make the country a globally important food exporter has led to the widespread expansion of agricultural surfaces over the last 20 years, thereby increasing pressure on limited water resources and water quality. Mining, being one of the most important economic sectors in <span class="hlt">Chile</span>, threatens both surface and groundwater quality. This scenario increases the potential for water use conflicts, which is further compounded by the demand for potable water provided by rivers and groundwater. In order to better understand the role of both physical and human dimensions of water quality, this research uses a socio-hydrological conceptual framework. This approach is used in order to broaden the scope of hydrology to include the anthropogenic impact on the environment. It therefore focuses on human and natural interactions and two-sided feedback loops, instead of purely hydrological cycles. Using the case study of the Rio Huasco watershed changes in water quality, which originate at the nexus of physical parameters, social conflicts and changing land use regimes in Northern <span class="hlt">Chile</span>, are discussed. This region was chosen as an exemplary case for the development of <span class="hlt">Chile</span>'s arid regions: the valley is located at the <span class="hlt">southern</span> edge of the Atacama Desert, where water scarcity is a major problem. At present, the watershed is predominantly used for agriculture. Many small farmers still practise strip cultivation, but are pressured to shift towards an international export-orientated future with monocultures. International companies are planning to mine the Pascua Lama Mine, one of the world's biggest gold reserves located in the headwaters of the Rio Huasco. Meanwhile, the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992CoMP..111..235I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992CoMP..111..235I"><span>Evolution of the upper mantle beneath the <span class="hlt">southern</span> Baikal rift <span class="hlt">zone</span>: an Sr-Nd isotope study of xenoliths from the Bartoy volcanoes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ionov, D. A.; Kramm, U.; Stosch, H.-G.</p> <p>1992-06-01</p> <p>Anhydrous and amphibole-bearing peridotite xenoliths occur in roughly equal quantitites in the Bartoy volcanic field about 100 km south of the <span class="hlt">southern</span> tip of Lake Baikal in Siberia (Russia). Whole-rock samples and pure mineral separates from nine xenoliths have been analyzed for Sr and Nd isotopes in order to characterize the upper mantle beneath the <span class="hlt">southern</span> Baikal rift <span class="hlt">zone</span>. In an Sr-Nd isotope diagram both dry and hydrous xenoliths from Bartoy plot at the junction between the fields of MORB and ocean island basalts. This contrasts with data available on two other localities around Lake Baikal (Tariat and Vitim) where peridotites typically have Sr-Nd isotope compositions indicative of strong long-term depletion in incompatible elements. Our data indicate significant chemical and isotopic heterogeneity in the mantle beneath Bartoy that may be attributed to its position close to an ancient suture <span class="hlt">zone</span> separating the Siberian Platform from the Mongol-Okhotsk mobile belt and occupied now by the Baikal rift. Two peridotites have clinopyroxenes depleted in light rare earth elements (LREE) with Sr and Nd model ages of about 2 Ga and seem to retain the trace element and isotopic signatures of old depleted lithospheric mantle, while all other xenoliths show different degrees of LREE-enrichment. Amphiboles and clinopyroxenes in the hydrous peridotites are in Sr-Nd isotopic disequilibrium. If this reflects in situ decay of 147Sm and 87Rb rather than heterogeneities produced by recent metasomatic formation of amphiboles then 300 400 Ma have passed since the minerals were last in equilibrium. This age range then indicates an old enrichment episode or repeated events during the Paleozoic in the lithospheric mantle initially depleted maybe ˜2 Ga ago. The Bartoy hydrous and enriched dry peridotites, therefore, are unlikely to represent fragments of a young asthenospheric bulge which, according to seismic reflection studies, reached the Moho at the axis of the Baikal rift <span class="hlt">zone</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26340665','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26340665"><span>Checklist, diversity and distribution of testate amoebae in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fernández, Leonardo D; Lara, Enrique; Mitchell, Edward A D</p> <p>2015-10-01</p> <p>Bringing together more than 170 years of data, this study represents the first attempt to construct a species checklist and analyze the diversity and distribution of testate amoebae in <span class="hlt">Chile</span>, a country that encompasses the southwestern region of South America, countless islands and part of the Antarctic. In <span class="hlt">Chile</span>, known diversity includes 416 testate amoeba taxa (64 genera, 352 infrageneric taxa), 24 of which are here reported for the first time. Species-accumulation plots show that in <span class="hlt">Chile</span>, the number of testate amoeba species reported has been continually increasing since the mid-19th century without leveling off. Testate amoebae have been recorded in 37 different habitats, though they are more diverse in peatlands and rainforest soils. Only 11% of species are widespread in continental <span class="hlt">Chile</span>, while the remaining 89% of the species exhibit medium or short latitudinal distribution ranges. Also, species composition of insular <span class="hlt">Chile</span> and the Chilean Antarctic territory is a depauperated subset of that found in continental <span class="hlt">Chile</span>. Nearly, the 10% of the species reported here are endemic to <span class="hlt">Chile</span> and many of them are distributed only within the so-called Chilean biodiversity hotspot (ca. 25° S-47° S). These findings are here thoroughly discussed in a biogeographical and evolutionary context. Copyright © 2015 Elsevier GmbH. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860053057&hterms=bouguer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbouguer','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860053057&hterms=bouguer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbouguer"><span>Structure of the <span class="hlt">southern</span> Rio Grande rift from gravity interpretation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Daggett, P. H.; Keller, G. R.; Wen, C.-L.; Morgan, P.</p> <p>1986-01-01</p> <p>Regional Bouguer gravity anomalies in <span class="hlt">southern</span> New Mexico have been analyzed by two-dimensional wave number filtering and poly-nomial trend surface analysis of the observed gravity field. A prominent, regional oval-shaped positive gravity anomaly was found to be associated with the <span class="hlt">southern</span> Rio Grande rift. Computer modeling of three regional gravity profiles suggests that this anomaly is due to crustal thinning beneath the <span class="hlt">southern</span> Rio Grande rift. These models indicate a 25 to 26-km minimum crustal thickness within the rift and suggest that the rift is underlain by a broad <span class="hlt">zone</span> of anomalously low-density upper mantle. The <span class="hlt">southern</span> terminus of the anomalous <span class="hlt">zone</span> is approximately 50 km southwest of El Paso, Texas. A thinning of the rifted crust of 2-3 km relative to the adjacent Basin and Range province indicates an extension of about 9 percent during the formation of the modern <span class="hlt">southern</span> Rio Grande rift. This extension estimate is consistent with estimates from other data sources. The crustal thinning and anomalous mantle is thought to result from magmatic activity related to surface volcanism and high heat flow in this area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5896900','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5896900"><span>An intragenic approach to confer glyphosate resistance in <span class="hlt">chile</span> (Capsicum annuum) by introducing an in vitro mutagenized <span class="hlt">chile</span> EPSPS gene encoding for a glyphosate resistant EPSPS protein</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bagga, Suman; Apodaca, Kimberly; Lucero, Yvonne</p> <p>2018-01-01</p> <p><span class="hlt">Chile</span> pepper (Capsicum annuum) is an important high valued crop worldwide, and when grown on a large scale has problems with weeds. One important herbicide used is glyphosate. Glyphosate inactivates the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), a key enzyme in the synthesis of aromatic amino acids. A transgenic approach towards making glyphosate resistant plants, entails introducing copies of a gene encoding for glyphosate-resistant EPSPS enzyme into the plant. The main objective of our work was to use an intragenic approach to confer resistance to glyphosate in <span class="hlt">chile</span> which would require using only <span class="hlt">chile</span> genes for transformation including the selectable marker. Tobacco was used as the transgenic system to identify different gene constructs that would allow for the development of the intragenic system for <span class="hlt">chile</span>, since <span class="hlt">chile</span> transformation is inefficient. An EPSPS gene was isolated from <span class="hlt">chile</span> and mutagenized to introduce substitutions that are known to make the encoded enzyme resistant to glyphosate. The promoter for EPSPS gene was isolated from <span class="hlt">chile</span> and the mutagenized <span class="hlt">chile</span> EPSPS cDNA was engineered behind both the CaMV35S promoter and the EPSPS promoter. The leaves from the transformants were checked for resistance to glyphosate using a cut leaf assay. In tobacco, though both gene constructs exhibited some degree of resistance to glyphosate, the construct with the CaMV35S promoter was more effective and as such <span class="hlt">chile</span> was transformed with this gene construct. The <span class="hlt">chile</span> transformants showed resistance to low concentrations of glyphosate. Furthermore, preliminary studies showed that the mutated EPSPS gene driven by the CaMV35S promoter could be used as a selectable marker for transformation. We have shown that an intragenic approach can be used to confer glyphosate-resistance in <span class="hlt">chile</span>. However, we need a stronger <span class="hlt">chile</span> promoter and a mutated <span class="hlt">chile</span> gene that encodes for a more glyphosate resistant EPSPS protein. PMID:29649228</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/7809525','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/7809525"><span>[New medical schools in <span class="hlt">Chile</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Castillo, P</p> <p>1994-03-01</p> <p>In <span class="hlt">Chile</span> there are six established medical schools at public (<span class="hlt">Chile</span>, Valparaiso and Temuco) or private (Catholic, Concepción and Austral) universities created between 1833 and 1971. Since 1990, three new medical schools (two private) were created and a fourth is projected, concerning the chilean medical corps. We present three position articles on the subject written by Dean Pedro Rosso, from the Catholic University, Dr Pedro Castillo, Chief of Human Resources of the Ministry of Health and Dean Alejandro Goic from the University of <span class="hlt">Chile</span>. Dean Rosso emphasizes the need to have assessment procedures that guarantee quality standards in the new medical schools. Dr Castillo attracts attention on preserving the compromise with the society, inherent to chilean medicine. Dean Goic analyzes systematically the reasons to prevent the proliferation of medical schools in the country, maintaining an equilibrium between freedom of teaching and public faith protection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23280290','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23280290"><span>Source apportionment of PM₁₀ and PM₂.₅ in a desert region in northern <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jorquera, Héctor; Barraza, Francisco</p> <p>2013-02-01</p> <p>Estimating contributions of anthropogenic sources to ambient particulate matter (PM) in desert regions is a challenging issue because wind erosion contributions are ubiquitous, significant and difficult to quantify by using source-oriented, dispersion models. A receptor modeling analysis has been applied to ambient PM(10) and PM(2.5) measured in an industrial <span class="hlt">zone</span> ~20 km SE of Antofagasta (23.63°S, 70.39°W), a midsize coastal city in northern <span class="hlt">Chile</span>; the monitoring site is within a desert region that extends from northern <span class="hlt">Chile</span> to <span class="hlt">southern</span> Perú. Integrated 24-hour ambient samples of PM(10) and PM(2.5) were taken with Harvard Impactors; samples were analyzed by X Ray Fluorescence, ionic chromatography (NO(3)(-) and SO(4)(=)), atomic absorption (Na(+), K(+)) and thermal optical transmission for elemental and organic carbon determination. Receptor modeling was carried out using Positive Matrix Factorization (US EPA Version 3.0); sources were identified by looking at specific tracers, tracer ratios, local winds and wind trajectories computed from NOAA's HYSPLIT model. For the PM(2.5) fraction, six contributions were found - cement plant, 33.7 ± 1.3%; soil dust, 22.4 ± 1.6%; sulfates, 17.8 ± 1.7%; mineral stockpiles and brine plant, 12.4 ± 1.2%; Antofagasta, 8.5 ± 1.3% and copper smelter, 5.3 ± 0.8%. For the PM(10) fraction five sources were identified - cement plant, 38.2 ± 1.5%; soil dust, 31.2 ± 2.3%; mineral stockpiles and brine plant, 12.7 ± 1.7%; copper smelter, 11.5 ± 1.6% and marine aerosol, 6.5 ± 2.4%. Therefore local sources contribute to ambient PM concentrations more than distant sources (Antofagasta, marine aerosol) do. Soil dust is enriched with deposition of marine aerosol and calcium, sulfates and heavy metals from surrounding industrial activities. The mean contribution of suspended soil dust to PM(10) is 50 μg/m(3) and the peak daily value is 104 μg/m(3). For the PM(2.5) fraction, suspended soil dust contributes with an average of 9.3 </p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011DSRII..58.2293H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011DSRII..58.2293H"><span>Distribution, abundance and seasonal flux of pteropods in the Sub-Antarctic <span class="hlt">Zone</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Howard, W. R.; Roberts, D.; Moy, A. D.; Lindsay, M. C. M.; Hopcroft, R. R.; Trull, T. W.; Bray, S. G.</p> <p>2011-11-01</p> <p>Pteropods were identified from epipelagic net and trawl samples in the Sub-Antarctic <span class="hlt">Zone</span> during the 2007 mid-summer (January 17-February 20) Sub-Antarctic <span class="hlt">Zone</span> Sensitivity to Environmental Change (SAZ-Sense) voyage, as well as in a moored sediment trap in the same region. Overall pteropod densities during SAZ-Sense were lower than those reported for higher-latitude <span class="hlt">Southern</span> Ocean waters. The four major contributors to the Sub-Antarctic <span class="hlt">Zone</span> pteropod community during the SAZ-Sense voyage, Clio pyramidata forma antarctica, Clio recurva, Limacina helicina antarctica and Limacina retroversa australis, accounted for 93% of all pteropods observed. The distribution of the two dominant pteropods collected in the Sub-Antarctic <span class="hlt">Zone</span>, L. retroversa australis and C. pyramidata forma antarctica, is strongly related to latitude and depth. L. retroversa australis is typical of cold <span class="hlt">southern</span> (50-54°S) polar waters and C. pyramidata forma antarctica is typical of shallow (top 20 m) Sub-Antarctic <span class="hlt">Zone</span> waters. A moored sediment trap deployed to 2100 m at 47°S, 141°E in 2003/04 showed the pteropod flux in the Sub-Antarctic <span class="hlt">Zone</span> had late-Spring and mid-summer peaks. The diversity, abundance and distribution of pteropods collected during SAZ-Sense provide a timely benchmark against which to monitor future changes in SAZ ocean pteropod communities, particularly in light of predictions of declining aragonite saturation in the <span class="hlt">Southern</span> Ocean by the end of the century.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2011-08-26/pdf/2011-21556.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2011-08-26/pdf/2011-21556.pdf"><span>76 FR 53381 - Endangered and Threatened Wildlife and Plants; Termination of the <span class="hlt">Southern</span> Sea Otter...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2011-08-26</p> <p>...We, the U.S. Fish and Wildlife Service (Service), propose to remove the regulations that govern the <span class="hlt">southern</span> sea otter (Enhydra lutris nereis) translocation program, including the establishment of an experimental population of <span class="hlt">southern</span> sea otters, and all associated management actions. We are also proposing to amend the Authority citation for 50 CFR part 17 by removing the reference to Public Law 99- 625, the statute that authorized the Secretary to promulgate regulations establishing the <span class="hlt">southern</span> sea otter translocation program. Removal of the regulations will terminate the program. We are proposing this action because we believe that the <span class="hlt">southern</span> sea otter translocation program has failed to fulfill its purpose, as outlined in the <span class="hlt">southern</span> sea otter translocation plan, and that our recovery and management goals for the species cannot be met by continuing the program. Our conclusion is based, in part, on an evaluation of the program against specific failure criteria established at the program's inception. This proposed action would terminate the designation of the experimental population of <span class="hlt">southern</span> sea otters, abolish the <span class="hlt">southern</span> sea otter translocation and management <span class="hlt">zones</span>, and eliminate the current requirement to remove <span class="hlt">southern</span> sea otters from San Nicolas Island and the management <span class="hlt">zone</span>. This proposed rule would also eliminate future actions, required under the current regulations, to capture and relocate <span class="hlt">southern</span> sea otters for the purpose of establishing an experimental population, and to remove <span class="hlt">southern</span> sea otters in perpetuity from an ``otter-free'' management <span class="hlt">zone</span>. As a result, it would allow <span class="hlt">southern</span> sea otters to expand their range naturally into <span class="hlt">southern</span> California waters. We have prepared a revised draft supplemental environmental impact statement (SEIS) and an initial regulatory flexibility analysis (IRFA) to accompany this proposed rule.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.2162R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.2162R"><span>The geothermal system of Caviahue-Copahue Volcanic Complex (<span class="hlt">Chile</span>-Argentina): New insights from self-potential, soil CO2 degassing, temperature measurements and helium isotopes, with structural and fluid circulation implications.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Roulleau, Emilie; Bravo, Francisco; Barde-Cabusson, Stephanie; Pizarro, Marcela; Muños, Carlos; Sanchez, Juan; Tardani, Daniele; Sano, Yuji; Takahata, Naoto; de Cal, Federico; Esteban, Carlos</p> <p>2016-04-01</p> <p>Geothermal systems represent natural heat transfer engines in a confined volume of rock which are strongly influenced by the regional volcano-tectonic setting controlling the formation of shallow magmatic reservoirs, and by the local faults/fracture network, that permits the development of hydrothermal circulation cells and promote the vertical migration of fluids and heat. In the <span class="hlt">Southern</span> Volcanic <span class="hlt">Zone</span> of <span class="hlt">Chile</span>-Argentina, geothermal resources occur in close spatial relationship with active volcanism along the Cordillera which is primarily controlled by the 1000 km long, NNE Liquiñe-Ofqui Fault <span class="hlt">Zone</span> (LOFZ), an intra-arc dextral strike-slip fault system, associated with second-order intra-arc anisotropy of overall NE-SW (extensional) and NW-SE orientation (compressional). However there is still a lack of information on how fault network (NE and WNW strinking faults) and lithology control the fluid circulation. In this study, we propose new data of dense self-potential (SP), soil CO2 emanation and temperature (T) measurements within the geothermal area from Caviahue-Copahue Volcanic Complex (CCVC), coupled with helium isotopes ratios measured in fumaroles and thermal springs. We observe that inside the geothermal system the NE-striking faults, characterized by a combination of SP-CO2 and T maxima with high 3He/4He ratios (7.86Ra), promote the formation of high vertical permeability pathways for fluid circulation. Whereas, the WNW-striking faults represent low permeability pathways for hydrothermal fluids ascent associated with moderate 3He/4He ratios (5.34Ra), promoting the infiltration of meteoric water at shallow depth. These active <span class="hlt">zones</span> are interspersed by SP-CO2- T minima, which represent self-sealed <span class="hlt">zones</span> (e.g. impermeable altered rocks) at depth, creating a barrier inhibiting fluids rise. The NE-striking faults seem to be associated with the upflow <span class="hlt">zones</span> of the geothermal system, where the boiling process produces a high vapor-dominated <span class="hlt">zone</span> close to the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19245635','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19245635"><span>A comparison of sea lice, Caligus rogercresseyi, fecundity in four areas in <span class="hlt">southern</span> <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bravo, S; Erranz, F; Lagos, C</p> <p>2009-01-01</p> <p>A survey was carried out between March 2006 and February 2007 on the fecundity of Caligus rogercresseyi in four areas of Region X (Lat 42 degrees S) in <span class="hlt">Chile</span>. An average length of 4.83 +/- 0.4 mm for gravid females and 4.78 +/- 0.56 mm for males was recorded from the four areas, with no significant differences in length between sexes. Although females were largest in spring and summer, egg strings were longer and there were higher number of eggs per string in winter. The lowest salinity values were recorded in the Hornopirén area, which had the largest gravid females and the highest number of eggs per string during the study. The number of lice treatments showed no influence on the fecundity rate in the four areas. Prevalence and abundance of C. rogercresseyi were influenced by salinity and temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoJI.199..219C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoJI.199..219C"><span>Evidences of a lithospheric fault <span class="hlt">zone</span> in the Sicily Channel continental rift (<span class="hlt">southern</span> Italy) from instrumental seismicity data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Calò, M.; Parisi, L.</p> <p>2014-10-01</p> <p>Sicily Channel is a portion of Mediterranean Sea, between Sicily (<span class="hlt">Southern</span> Italy) and Tunisia, representing a part of the foreland Apennine-Maghrebian thrust belt. The seismicity of the region is commonly associated with the normal faulting related to the rifting process and volcanic activity of the region. However, certain seismic patterns suggest the existence of some mechanism coexisting with the rifting process. In this work, we present the results of a statistical analysis of the instrumental seismicity and a reliable relocalization of the events recorded in the last 30 yr in the Sicily Channel and western Sicily using the Double Difference method and 3-D Vp and Vs tomographic models. Our procedure allows us to discern the seismic regime of the Sicily sea from the Tyrrhenian one and to describe the main features of an active fault <span class="hlt">zone</span> in the study area that could not be related to the rifting process. We report that most of the events are highly clustered in the region between 12.5°-13.5°E and 35.5°-37°N with hypocentral depth of 5-40 km, and reaching 70 km depth in the southernmost sector. The alignment of the seismic clusters, the distribution of volcanic and geothermal regions and the location of some large events occurred in the last century suggest the existence of a subvertical shear <span class="hlt">zone</span> extending for least 250 km and oriented approximately NNE-SSW. The spatial distribution of the seismic moment suggests that this transfer fault <span class="hlt">zone</span> is seismically discontinuous showing large seismic gaps in proximity of the Ferdinandea Island, and Graham and Nameless Bank.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.T14D..03W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.T14D..03W"><span>Slip <span class="hlt">Zone</span> versus Damage <span class="hlt">Zone</span> Micromechanics, Arima-Takasuki Tectonic Line, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>White, J. C.; Lin, A.</p> <p>2017-12-01</p> <p>The Arima-Takasuki Tectonic Line (ATTL) of <span class="hlt">southern</span> Honshu, Japan is defined by historically active faults and multiple splays producing M7 earthquakes. The damage <span class="hlt">zone</span> of the ATTL comprises a broad <span class="hlt">zone</span> of crushed, comminuted and pulverized granite/rhyolite1,2containing cm-scale slip <span class="hlt">zones</span> and highly comminuted injection veins. In this presentation, prior work on the ATTL fault rocks is extending to include microstructural characterization by transmission electron microscopy (TEM) from recent trenching of the primary slip <span class="hlt">zone</span>, as well as secondary slip <span class="hlt">zones</span>. This is necessary to adequately characterize the extremely fine-grained material (typically less than 1mm) in both damage and core <span class="hlt">zones</span>. Damage <span class="hlt">zone</span> material exhibits generally random textures3 whereas slip <span class="hlt">zones</span> are macroscopically foliated, and compositionally layered, notwithstanding a fairly homogeneous protolith. The latter reflects fluid-rock interaction during both coseismic and interseismic periods. The slip <span class="hlt">zones</span> are microstructurally heterogeneous at all scales, comprising not only cataclasites and phyllosilicate (clay)-rich gouge <span class="hlt">zones</span>, but Fe/Mn pellets or clasts that are contained within gouge. These structures appear to have rolled and would suggest rapid recrystallization and/or growth. A central question related to earthquake recurrence along existing faults is the nature of the gouge. In both near-surface exposures and ongoing drilling at depth, "plastic" or "viscous" gouge <span class="hlt">zones</span> comprise ultra-fine-grained clay-siliciclastic particles that would not necessarily respond in a simple frictional manner. Depending on whether the plastic nature of these slip <span class="hlt">zones</span> develops during or after slip, subsequent focusing of slip within them could be complicated. 1 Mitchell, T.A., Ben-Zion, Y., Shimamoto, T., 2011. Ear. Planet. Sci. Lett. 308, 284-297. 2 Lin, A., Yamashita, K, Tanaka, M. J., 2013. Struc. Geol. 48, 3-13. 3 White, J.C., Lin, A. 2016. Proc. AGU Fall Mtg., T42-02 San Francisco.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850005099','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850005099"><span>Archean sedimentation and tectonics in <span class="hlt">southern</span> Africa</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kidd, W. S. F.</p> <p>1984-01-01</p> <p>Sequences in the Barberton Mountain Land greenstone belt (<span class="hlt">southern</span> Africa) were examined to determine the nature of the sedimentary rocks, their tectonic implications, and their bearing on the present large-scale structural condition of the belt. Also assessed was whether there was evidence for a significant component of shallow-water-deposited sedimentary rocks in the parent materials of the Limpopo belt. The nature of a largehigh strain <span class="hlt">zone</span> on the <span class="hlt">southern</span> margin of the central Limpopo belt was examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=GL-2002-002222&hterms=Bloom+Chile&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DBloom%2BChile','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=GL-2002-002222&hterms=Bloom+Chile&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DBloom%2BChile"><span>Central <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2002-01-01</p> <p>The beginning of spring in central <span class="hlt">Chile</span> looked like this to SeaWiFS. The snow-covered Andes mark the country's eastern border, and phytoplankton blooms and river sediment plumes fill the waters off its west coast. A large eddy due west of Concepcion is highlighted by the phytoplankton it contains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JVGR..349..392M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JVGR..349..392M"><span>Volcanologic and petrologic evolution of Antuco-Sierra Velluda, <span class="hlt">Southern</span> Andes, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martínez, Paola; Singer, Brad S.; Roa, Hugo Moreno; Jicha, Brian R.</p> <p>2018-01-01</p> <p>The Andean <span class="hlt">Southern</span> Volcanic <span class="hlt">Zone</span> comprises > 30 active arc front volcanoes that grew over periods of hundreds of thousands of years. Quantifying the rates at which these volcanoes grow is key to appreciating geological hazards, clarifying petrologic evolution, and exploring possible relationships between volcanism, ice loading, and climate. The integration of precise geochronology and geologic mapping, together with new lava compositions and volume estimates, reveal the evolution of the Antuco-Sierra Velluda volcanic complex at 37.2°S. Thirty-one new 40Ar/39Ar age determinations illuminate a punctuated eruptive history that spans at least 430 kyr. Sierra Velluda comprises 130 km3 and began to grow prior to 426.8 ka. A lacuna in the volcanic record between 343.5 and 150.4 ka coincides with glaciations associated with marine isotope stages (MIS) 10 and 8, although shallow intrusions were emplaced at 207.0 and 190.0 ka. Antuco began to grow rapidly on the northeast flank of Sierra Velluda, erupting > 60 km3 of lava during three phases: (1) an early phase that began at 150.4 ka, (2) a post-MIS 2 phase between 16.3 and 6.2 ka, and (3) a post-sector collapse phase after 6.2 ka. Volcanism has been continuous during the last 100 kyr, with an average rate of cone growth during this period of 0.46 km3/kyr that has accelerated by about 50% during the past 6 kyr. Whereas Sierra Velluda erupted basaltic andesitic to andesitic (53.5 to 58.7 wt% SiO2) lavas, during the last expansion of glaciers between 130 and 17 ka, Early Antuco erupted a wider spectrum of lavas, ranging from basaltic andesite to dacite (52.0 to 64.5 wt% SiO2). Notably, eruptions following the last glacial termination at 17 ka produced basalts and basaltic andesites (50.9-53.7% SiO2), and following the 6.2 ka cone collapse they have been exclusively olivine basalt (50.9-53.0% SiO2) with > 5 wt% MgO. Thermodynamic and trace element modeling suggests that lavas from Sierra Velluda and Early Antuco reflect</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22069808','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22069808"><span>Putting the market in its place: food security in three Mapuche communities in <span class="hlt">southern</span> <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Clark, Timothy David</p> <p>2011-01-01</p> <p>This article analyzes the impact of state policies since the 1970s on household food security in several Mapuche communities in the Araucanía region of <span class="hlt">Chile</span> (Region IX). The author highlights key transformations in the national economy and food system and endeavors to link those to local phenomena, in particular the absorption of the local livelihood strategies and food systems into capitalist markets and the high incidences of food insecurity. The article concludes that a reconceptualization of macroeconomic and indigenous policies are required to rebuild the material and social foundations of rural Mapuche communities that provide the bases from which their inhabitants can reconstruct a mutually beneficial relationship with the broader Chilean society and avert the continued acceleration of tension and violence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013BGeo...10..803P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013BGeo...10..803P"><span>Late summer particulate organic carbon export and twilight <span class="hlt">zone</span> remineralisation in the Atlantic sector of the <span class="hlt">Southern</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Planchon, F.; Cavagna, A.-J.; Cardinal, D.; André, L.; Dehairs, F.</p> <p>2013-02-01</p> <p>As part of the GEOTRACES Bonus-GoodHope (BGH) expedition (January-March 2008) in the Atlantic sector of the <span class="hlt">Southern</span> Ocean, particulate organic carbon (POC) export was examined from the surface to the mesopelagic twilight <span class="hlt">zone</span> using water column distributions of total 234Th and biogenic particulate Ba (Baxs). Surface POC export production was estimated from steady state and non steady state modelling of 234Th fluxes, which were converted into POC fluxes, using the POC/234Th ratio of large, potentially sinking particles (> 53 μm) collected via in situ pumps. Deficits in 234Th activities were observed at all stations from the surface to the bottom of the mixed layer, yielding 234Th export fluxes from the upper 100 m of 496 ± 214 dpm m-2 d-1 to 1195 ± 158 dpm m-2 d-1 for the steady state model and of 149 ±517 dpm m-2 d-1 to 1217 ± 231 dpm m-2 d-1 for the non steady state model. Using the POC/234Thp ratio of sinking particles (ratios varied from 1.7 ± 0.2 μmol dpm-1 to 4.8 ± 1.9 μmol dpm-1) POC export production at 100 m was calculated to range between 0.9 ± 0.4 and 5.1 ± 2.1 mmol C m-2 d-1,assuming steady state and between 0.3 ± 0.9 m-2 d-1 and 4.9 ± 3.3 mmol C m-2 d-1, assuming non steady state. From the comparison of both approaches, it appears that during late summer export decreased by 56 to 16% for the area between the sub-Antarctic <span class="hlt">zone</span> and the <span class="hlt">southern</span> Antarctic Circumpolar Current Front (SACCF), whereas it remained rather constant over time in the HNLC area south of the SACCF. POC export represented only 6 to 54% of new production, indicating that export efficiency was, in general, low, except in the vicinity of the SACCF, where export represented 56% of new production. Attenuation of the POC sinking flux in the upper mesopelagic waters (100-600 m depth interval) was evidenced both, from excess 234Th activities and from particulate biogenic Ba (Baxs) accumulation. Excess 234Th activities, reflected by 234Th/238U ratios as large as 1.21 ± 0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Tectp.671...42B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Tectp.671...42B"><span>A refinement of the chronology of rift-related faulting in the Broadly Rifted <span class="hlt">Zone</span>, <span class="hlt">southern</span> Ethiopia, through apatite fission-track analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Balestrieri, Maria Laura; Bonini, Marco; Corti, Giacomo; Sani, Federico; Philippon, Melody</p> <p>2016-03-01</p> <p>To reconstruct the timing of rift inception in the Broadly Rifted <span class="hlt">Zone</span> in <span class="hlt">southern</span> Ethiopia, we applied the fission-track method to basement rocks collected along the scarp of the main normal faults bounding (i) the Amaro Horst in the <span class="hlt">southern</span> Main Ethiopian Rift and (ii) the Beto Basin in the Gofa Province. At the Amaro Horst, a vertical traverse along the major eastern scarp yielded pre-rift ages ranging between 121.4 ± 15.3 Ma and 69.5 ± 7.2 Ma, similarly to two other samples, one from the western scarp and one at the <span class="hlt">southern</span> termination of the horst (103.4 ± 24.5 Ma and 65.5 ± 4.2 Ma, respectively). More interestingly, a second traverse at the Amaro northeastern terminus released rift-related ages spanning between 12.3 ± 2.7 and 6.8 ± 0.7 Ma. In the Beto Basin, the ages determined along the base of the main (northwestern) fault scarp vary between 22.8 ± 3.3 Ma and 7.0 ± 0.7 Ma. We ascertain through thermal modeling that rift-related exhumation along the northwestern fault scarp of the Beto Basin started at 12 ± 2 Ma while in the eastern margin of the Amaro Horst faulting took place later than 10 Ma, possibly at about 8 Ma. These results suggest a reconsideration of previous models on timing of rift activation in the different sectors of the Ethiopian Rift. Extensional basin formation initiated more or less contemporaneously in the Gofa Province (~ 12 Ma) and Northern Main Ethiopian Rift (~ 10-12 Ma) at the time of a major reorganization of the Nubia-Somalia plate boundary (i.e., 11 ± 2 Ma). Afterwards, rift-related faulting involved the <span class="hlt">Southern</span> MER (Amaro Horst) at ~ 8 Ma, and only later rifting seemingly affected the Central MER (after ~ 7 Ma).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009JGRB..114.5405S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009JGRB..114.5405S"><span>Determination of the pore fluid pressure ratio at seismogenic megathrusts in subduction <span class="hlt">zones</span>: Implications for strength of asperities and Andean-type mountain building</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seno, Tetsuzo</p> <p>2009-05-01</p> <p>We construct the differential stress profile across the fore arc in a subduction <span class="hlt">zone</span> from the force balance between the shear stress, τ, at seismogenic megathrust and the lithostatic pressure. We assume that τ is written by μ (1 - λ) σn, where λ is the pore fluid pressure ratio, μ is the coefficient of static friction, and σn is the normal stress. Given a density structure of the fore-arc wedge, we determine λ by comparing calculated fore-arc stresses with observed ones, as 0.95-0.98 in Shikoku, Miyagi, Peru, north <span class="hlt">Chile</span>, and south <span class="hlt">Chile</span> and 0.90-0.93 in south Vancouver Island and Washington. The parameter τ averaged over the seismogenic megathrust is of the order of ˜10 MPa. Stress drops of great earthquakes in these <span class="hlt">zones</span> occupy 14-87% and not a constant fraction of τ. They, on the other hand, increase linearly with 1 - λ. We propose a simple fault model in which the area of asperities as a fraction of the total fault area is proportional to 1 - λ. Variation of fractional area of asperities thus may explain the observed correlation and the regional variation of λ. Assuming that the differential stress at summit of the Andean mountains is zero, not at the coast as observed at present, we determine λ to be 0.84 in north <span class="hlt">Chile</span> in the mountain building stage. Such a smaller value of λ, along with λ < ˜0.4 in collision <span class="hlt">zones</span> previously obtained and >˜0.9 in subduction <span class="hlt">zones</span>, would suggest that variation of λ controls the tectonic style of the Earth.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=operations+AND+planning&pg=3&id=ED581620','ERIC'); return false;" href="https://eric.ed.gov/?q=operations+AND+planning&pg=3&id=ED581620"><span>OECD Reviews of School Resources: <span class="hlt">Chile</span> 2017</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Santiago, Paulo; Fiszbein, Ariel; Jaramillo, Sandra García; Radinger, Thomas</p> <p>2017-01-01</p> <p>This country review report for <span class="hlt">Chile</span> provides, from an international perspective, an independent analysis of major issues facing the use of school resources in <span class="hlt">Chile</span>, current policy initiatives, and possible future approaches. The report serves three purposes: i) to provide insights and advice to Chilean education authorities; ii) to help other…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=education+AND+system+AND+united+AND+states&pg=4&id=EJ1132409','ERIC'); return false;" href="https://eric.ed.gov/?q=education+AND+system+AND+united+AND+states&pg=4&id=EJ1132409"><span>A Partnership for a Community College in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>McCrink, Carmen L.; Whitford, Heidi</p> <p>2017-01-01</p> <p>This chapter describes the results of case study research on a partnership between a community college in the United States and a university in <span class="hlt">Chile</span> that attempted to develop the first community college system in <span class="hlt">Chile</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70041667','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70041667"><span>Interdisciplinary studies of eruption at Chaitén volcano, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Pallister, John S.; Major, Jon J.; Pierson, Thomas C.; Holitt, Richard P.; Lowenstern, Jacob B.; Eichelberger, John C.; Luis, Lara; Moreno, Hugo; Muñoz, Jorge; Castro, Jonathan M.; Iroumé, Andrés; Andreoli, Andrea; Jones, Julia; Swanson, Fred; Crisafulli, Charlie</p> <p>2010-01-01</p> <p>High-silica rhyolite magma fuels Earth's largest and most explosive eruptions. Recurrence intervals for such highly explosive eruptions are in the 100- to 100,000-year time range, and there have been few direct observations of such eruptions and their immediate impacts. Consequently, there was keen interest within the volcanology community when the first large eruption of high-silica rhyolite since that of Alaska's Novarupta volcano in 1912 began on 1 May 2008 at Chaitén volcano, <span class="hlt">southern</span> <span class="hlt">Chile</span>, a 3-kilometer-diameter caldera volcano with a prehistoric record of rhyolite eruptions [Naranjo and Stern, 2004semi; Servicio Nacional de Geología y Minería (SERNAGEOMIN), 2008semi; Carn et al., 2009; Castro and Dingwell, 2009; Lara, 2009; Muñoz et al., 2009]. Vigorous explosions occurred through 8 May 2008, after which explosive activity waned and a new lava dome was extruded.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.epa.gov/international-cooperation/documents-chile-public-participation-training-chile-january-2013','PESTICIDES'); return false;" href="https://www.epa.gov/international-cooperation/documents-chile-public-participation-training-chile-january-2013"><span>Documents from <span class="hlt">Chile</span> Public Participation Training – <span class="hlt">Chile</span> – January 2013</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>EPA delivered a two-day workshop in <span class="hlt">Chile</span>, on public participation. The course intended to enable students to increase the level of public impact through the levels of public participation, found on EPA’s Public Participation Guide.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S11B2374N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S11B2374N"><span>A comparison of seismicity in world's subduction <span class="hlt">zones</span>: Implication by the difference of b-values</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nishikawa, T.; Ide, S.</p> <p>2013-12-01</p> <p>Since the pioneering study of Uyeda and Kanamori (1979), it has been thought that world's subduction <span class="hlt">zones</span> can be classified into two types: <span class="hlt">Chile</span> and Mariana types. Ruff and Kanamori (1980) suggested that the maximum earthquake size within each subduction <span class="hlt">zone</span> correlates with convergence rate and age of subducting lithosphere. Subduction <span class="hlt">zones</span> with younger lithosphere and larger convergence rates are associated with great earthquakes (<span class="hlt">Chile</span>), while subduction <span class="hlt">zones</span> with older lithosphere and smaller convergence rates have low seismicity (Mariana). However, these correlations are obscured after the 2004 Sumatra earthquake and the 2009 Tohoku earthquake. Furthermore, McCaffrey (2008) pointed out that the history of observation is much shorter than the recurrence times of very large earthquakes, suggesting a possibility that any subduction <span class="hlt">zone</span> may produce earthquakes larger than magnitude 9. In the present study, we compare world's subduction <span class="hlt">zones</span> in terms of b-values in the Gutenberg-Richer relation. We divided world's subduction <span class="hlt">zones</span> into 146 regions, each of which is bordered by a trench section of about 500 km and extends for 200 km from the trench section in the direction of relative plate motion. In each region, earthquakes equal to or larger than M4.5 occurring during 1988-2009 were extracted from ISC catalog. We find a positive correlation between b-values and ages of subducting lithosphere, which is one of the two important variables discussed in Ruff and Kanamori (1980). Subduction <span class="hlt">zones</span> with younger lithosphere are associated with high b-values and vice versa, while we cannot find a correlation between b-values and convergence rates. We used the ages determined by Müller et al. (2008) and convergence rate calculated using PB2002 (Bird, 2003) for convergence rate. We also found a negative correlation between b-values and the estimates of seismic coupling, which is defined as the ratio of the observed seismic moment release rate to the rate calculated</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70026869','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70026869"><span>The offshore Palos Verdes fault <span class="hlt">zone</span> near San Pedro, <span class="hlt">Southern</span> California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Fisher, M.A.; Normark, W.R.; Langenheim, V.E.; Calvert, A.J.; Sliter, R.</p> <p>2004-01-01</p> <p>High-resolution seismic-reflection data are combined with a variety of other geophysical and geological data to interpret the offshore structure and earthquake hazards of the San Pedro shelf, near Los Angeles, California. Prominent structures investigated include the Wilmington graben, the Palos Verdes fault <span class="hlt">zone</span>, various faults below the west part of the San Pedro shelf and slope, and the deep-water San Pedro basin. The structure of the Palos Verdes fault <span class="hlt">zone</span> changes markedly along strike southeastward across the San Pedro shelf and slope. Under the north part of the shelf, this fault <span class="hlt">zone</span> includes several strands, with the main strand dipping west. Under the slope, the main fault strands exhibit normal separation and mostly dip east. To the southeast near Lasuen Knoll, the Palos Verdes fault <span class="hlt">zone</span> locally is low angle, but elsewhere near this knoll, the fault dips steeply. Fresh seafloor scarps near Lasuen Knoll indicate recent fault movement. We explain the observed structural variation along the Palos Verdes fault <span class="hlt">zone</span> as the result of changes in strike and fault geometry along a master right-lateral strike-slip fault at depth. Complicated movement along this deep fault <span class="hlt">zone</span> is suggested by the possible wave-cut terraces on Lasuen Knoll, which indicate subaerial exposure during the last sea level lowstand and subsequent subsidence of the knoll. Modeling of aeromagnetic data indicates a large magnetic body under the west part of the San Pedro shelf and upper slope. We interpret this body to be thick basalt of probable Miocene age. This basalt mass appears to have affected the pattern of rock deformation, perhaps because the basalt was more competent during deformation than the sedimentary rocks that encased the basalt. West of the Palos Verdes fault <span class="hlt">zone</span>, other northwest-striking faults deform the outer shelf and slope. Evidence for recent movement along these faults is equivocal, because we lack age dates on deformed or offset sediment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25888965','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25888965"><span>Isolation of Leptospira interrogans serovar Hardjoprajitno from a calf with clinical leptospirosis in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Salgado, Miguel; Otto, Barbara; Moroni, Manuel; Sandoval, Errol; Reinhardt, German; Boqvist, Sofia; Encina, Carolina; Muñoz-Zanzi, Claudia</p> <p>2015-03-18</p> <p>Although Leptospira isolation has been reported in Chilean cattle, only serological evidence of serovar Hardjo bovis infection has been routinely reported. The present report provides characterization of the pathological presentation and etiology of a clinical case of leptospirosis in a calf from the Los Rios Region in <span class="hlt">Chile</span>. In a dairy herd in <span class="hlt">southern</span> <span class="hlt">Chile</span>, 11 of 130 calves died after presenting signs such as depression and red-tinged urine. One of these calves, a female of eight months, was necropsied, and all the pathological findings were consistent with Leptospira infection. A urine sample was submitted to conventional bacteriological analysis together with highly specific molecular biology typing tools, in order to unravel the specific Leptospira specie and serovar associated with this clinical case. A significant finding of this study was that the obtained isolate was confirmed by PCR as L. interrogans, its VNTR profile properly matching with L. interrogans Hardjoprajitno as well as its specific genomic identity revealed by secY gen. Leptospira interrogans serovar Hardjoprajitno was associated with the investigated calf clinical case. This information adds to the value of serologic results commonly reported, which encourage vaccination improvements to match circulating strains. In addition, this finding represents the first case report of this serovar in Chilean cattle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70017148','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70017148"><span>Discordant 14C ages from buried tidal-marsh soils in the Cascadia subduction <span class="hlt">zone</span>, <span class="hlt">southern</span> Oregon coast</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nelson, A.R.</p> <p>1992-01-01</p> <p>Peaty, tidal-marsh soils interbedded with estuarine mud in late Holocene stratigraphic sequences near Coos Bay, Oregon, may have been submerged and buried during great (M > 8) subduction earthquakes, smaller localized earthquakes, or by nontectonic processes. Radiocarbon dating might help distinguish among these alternatives by showing that soils at different sites were submerged at different times along this part of the Cascadia subduction <span class="hlt">zone</span>. But comparison of conventional 14C ages for different materials from the same buried soils shows that they contain materials that differ in age by many hundreds of years. Errors in calibrated soil ages represent about the same length of time as recurrence times for submergence events (150-500 yr)-this similarity precludes using conventional 14C ages to distinguish buried soils along the <span class="hlt">southern</span> Oregon coast. Accelerator mass spectrometer 14C ages of carefully selected macrofossils from the tops of peaty soils should provide more precise estimates of the times of submergence events. ?? 1992.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29546918','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29546918"><span>[Health inequality gap in inmigrant versus local children in <span class="hlt">Chile</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cabieses, Baltica; Chepo, Macarena; Oyarte, Marcela; Markkula, Niina; Bustos, Patricia; Pedrero, Víctor; Delgado, Iris</p> <p>2017-12-01</p> <p>Children and young international migrants face different health challenges compa red with the local population, particularly if they live in insecure environments or adverse social conditions. This study seeks to identify gaps in health outcomes of children between immigrant and local population in <span class="hlt">Chile</span>. This study analyses data from three sources: (i) Born in <span class="hlt">Chile</span>: Electronic records of antenatal visits from all municipal antenatal clinics of Recoleta in 2012; (ii) Growing up in <span class="hlt">Chile</span>: Population survey "National Socioeconomic Characterization" (CASEN) from 2013 and (iii) Getting sick in <span class="hlt">Chile</span>: Data of all hospital discharges in 2012, provided by the department of statistics and health information (DEIS) of the Ministry of Health. (I) Born in <span class="hlt">Chile</span>: Im migrants more frequently have psychosocial risk (62.3% vs 50.1% in Chileans) and enter later into the program (63.1% vs 33.4% enter later than 14 weeks of pregnancy). All birth outcomes were better among immigrants (e.g. caesarean sections rates: 24.2% immigrants vs % Chileans). (ii) Growing up in <span class="hlt">Chile</span>: A higher proportion of migrant children is outside the school system and lives in multidi mensional poverty (40% immigrants vs 23.2% Chileans). (iii) Getting sick in <span class="hlt">Chile</span>: Injuries and other external causes were more frequent cause of hospitalisation among migrants (23.6%) than the local population (16.7%) aged between 7 and 14 years. Addressing the needs of the children in <span class="hlt">Chile</span>, regardless of their immigration status, is an ethical, legal and moral imperative.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70036335','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70036335"><span>Estimates of stress drop and crustal tectonic stress from the 27 February 2010 Maule, <span class="hlt">Chile</span>, earthquake: Implications for fault strength</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Luttrell, K.M.; Tong, X.; Sandwell, D.T.; Brooks, B.A.; Bevis, M.G.</p> <p>2011-01-01</p> <p>The great 27 February 2010 Mw 8.8 earthquake off the coast of <span class="hlt">southern</span> <span class="hlt">Chile</span> ruptured a ???600 km length of subduction <span class="hlt">zone</span>. In this paper, we make two independent estimates of shear stress in the crust in the region of the <span class="hlt">Chile</span> earthquake. First, we use a coseismic slip model constrained by geodetic observations from interferometric synthetic aperture radar (InSAR) and GPS to derive a spatially variable estimate of the change in static shear stress along the ruptured fault. Second, we use a static force balance model to constrain the crustal shear stress required to simultaneously support observed fore-arc topography and the stress orientation indicated by the earthquake focal mechanism. This includes the derivation of a semianalytic solution for the stress field exerted by surface and Moho topography loading the crust. We find that the deviatoric stress exerted by topography is minimized in the limit when the crust is considered an incompressible elastic solid, with a Poisson ratio of 0.5, and is independent of Young's modulus. This places a strict lower bound on the critical stress state maintained by the crust supporting plastically deformed accretionary wedge topography. We estimate the coseismic shear stress change from the Maule event ranged from-6 MPa (stress increase) to 17 MPa (stress drop), with a maximum depth-averaged crustal shear-stress drop of 4 MPa. We separately estimate that the plate-driving forces acting in the region, regardless of their exact mechanism, must contribute at least 27 MPa trench-perpendicular compression and 15 MPa trench-parallel compression. This corresponds to a depth-averaged shear stress of at least 7 MPa. The comparable magnitude of these two independent shear stress estimates is consistent with the interpretation that the section of the megathrust fault ruptured in the Maule earthquake is weak, with the seismic cycle relieving much of the total sustained shear stress in the crust. Copyright 2011 by the American</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.epa.gov/international-cooperation/documents-chile-public-participation-training-chile-march-2011','PESTICIDES'); return false;" href="https://www.epa.gov/international-cooperation/documents-chile-public-participation-training-chile-march-2011"><span>Documents from <span class="hlt">Chile</span> Public Participation Training – <span class="hlt">Chile</span> – March 2011</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>EPA delivered a two-day workshop in Santiago, <span class="hlt">Chile</span>, on public participation. The course intended to enable students to increase the level of public impact through the levels of public participation, found on EPA’s Public Participation Guide.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29093511','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29093511"><span>A solar radiation database for <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Molina, Alejandra; Falvey, Mark; Rondanelli, Roberto</p> <p>2017-11-01</p> <p><span class="hlt">Chile</span> hosts some of the sunniest places on earth, which has led to a growing solar energy industry in recent years. However, the lack of high resolution measurements of solar irradiance becomes a critical obstacle for both financing and design of solar installations. Besides the Atacama Desert, <span class="hlt">Chile</span> displays a large array of "solar climates" due to large latitude and altitude variations, and so provides a useful testbed for the development of solar irradiance maps. Here a new public database for surface solar irradiance over <span class="hlt">Chile</span> is presented. This database includes hourly irradiance from 2004 to 2016 at 90 m horizontal resolution over continental <span class="hlt">Chile</span>. Our results are based on global reanalysis data to force a radiative transfer model for clear sky solar irradiance and an empirical model based on geostationary satellite data for cloudy conditions. The results have been validated using 140 surface solar irradiance stations throughout the country. Model mean percentage error in hourly time series of global horizontal irradiance is only 0.73%, considering both clear and cloudy days. The simplicity and accuracy of the model over a wide range of solar conditions provides confidence that the model can be easily generalized to other regions of the world.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2735183','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2735183"><span>Ancient Leishmaniasis in a Highland Desert of Northern <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Costa, Maria Antonietta; Matheson, Carney; Iachetta, Lucia; Llagostera, Agustín; Appenzeller, Otto</p> <p>2009-01-01</p> <p>Background Leishmaniasis is an infectious disease endemic today in many areas of South America. Methodology We discovered morphologic and molecular evidence of ancient infections in 4 female skulls in the archaeological cemetery of Coyo Oriente, in the desert of San Pedro de Atacama, Northern <span class="hlt">Chile</span>. The boney facial lesions visible in the skulls could have been caused by a number of chronic infections including chronic Leishmaniasis. This diagnosis was confirmed using PCR-sequenced analyses of bone fragments from the skulls of the affected individuals.Leishmaniasis is not normally found in the high-altitude desert of Northern <span class="hlt">Chile</span>; where the harsh climate does not allow the parasite to complete its life cycle. The presence of Leishmaniasis in ancient skulls from the region implies infection by the protozoan in an endemic area–likely, in our subjects, to have been the lowlands of North-Eastern Argentina or in <span class="hlt">Southern</span> Bolivia. Conclusions We propose that the presence of the disease in ancient times in the high altitude desert of San Pedro de Atacama is the result of an exogamic system of patrilocal marriages, where women from different cultures followed their husbands to their ancestral homes, allowing immigrant women, infected early in life, to be incorporated in the Atacama desert society before they became disfigured by the disease. The present globalization of goods and services and the extraordinary facile movement of people across borders and continents have lead to a resurgence of infectious diseases and re-emergence of infections such as Leishmaniasis. We show here that such factors were already present millennia ago, shaping demographic trends and the epidemiology of infections just as they do today. PMID:19746163</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JMS...148..200R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JMS...148..200R"><span>Egg production and hatching success of Calanus chilensis and Acartia tonsa in the northern <span class="hlt">Chile</span> upwelling <span class="hlt">zone</span> (23°S), Humboldt Current System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruz, Paula M.; Hidalgo, Pamela; Yáñez, Sonia; Escribano, Rubén; Keister, Julie E.</p> <p>2015-08-01</p> <p>Oxygen Minimum <span class="hlt">Zones</span> (OMZ's) are expanding and intensifying as result of climate change, affecting Eastern Boundary Upwelling Systems. Local effects of vertical movements of OMZ's that result from changes in upwelling intensity could reduce or expand the oxygenated surface layer that most zooplanktonic species inhabit in coastal areas. Using the copepods Calanus chilensis and Acartia tonsa as model organisms, an experimental test of the impact of different dissolved oxygen (DO) concentrations (between 0.5 and 5 ml L- 1) on egg production and hatching success was carried out and compared with field estimations of egg production, female and egg abundance in Mejillones Bay (23°S). Abundance of C. chilensis was highly variability and no consistent pattern in egg production and hatching success was found across DO levels, whereas A. tonsa egg production had maximum values between 2.6 and 4.7 ml O2 L- 1 and hatching success was positively correlated with DO (r = 0.75). In the field, temperature was the main factor controlling the dynamics of both species, while Chl-a and DO were also correlated with C. chilensis and A. tonsa, respectively. Principal Component Analysis showed that abundances of both copepods were controlled by temperature, stratification, OMZ depth, and Ekman transport, which together explained more than 70% of the total variance and were the main factors that modulated the populations of C. chilensis and A. tonsa in the upwelling <span class="hlt">zone</span> of northern <span class="hlt">Chile</span> (23°S). The differential responses of C. chilensis and A. tonsa to changes in DO concentrations associated with vertical movements of the OMZ suggest that C. chilensis may be better adapted to hypoxic conditions than A. tonsa, however both species are successful and persistent all year-round. We suggest that physiological responses of copepods could be used to evaluate population dynamics affected by the shoaling of OMZ's and the repercussions to trophic food webs of eastern boundary current systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.acap.aq/en/search14?q=First+steps+for+mitigating+bycatch+of+Pink-footed+Shearwaters+Ardenna+creatopus%3A+Identifying+overlap+of+foraging+areas+and+fisheries+in+Chile','USGSPUBS'); return false;" href="http://www.acap.aq/en/search14?q=First+steps+for+mitigating+bycatch+of+Pink-footed+Shearwaters+Ardenna+creatopus%3A+Identifying+overlap+of+foraging+areas+and+fisheries+in+Chile"><span>First steps for mitigating bycatch of Pink-footed Shearwaters Ardenna creatopus: Identifying overlap of foraging areas and fisheries in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Carle, Ryan; Felis, Jonathan J.; López, Verónica; Adams, Josh; Hodum, Peter; Beck, Jessie; Colodro, Valentina; Vega, Rodrigo; González, Andrés</p> <p>2016-01-01</p> <p>The Pink-footed Shearwater, Ardenna creatopus, is listed as in danger of extinction by <span class="hlt">Chile</span> and under Annex 1 of ACAP, with an estimated global population of approximately 56,000 individuals. Incidental bycatch of this species in fisheries is thought to be an important cause in population decline (i.e. annual estimated mortality of >1000 adults). This species is an endemic breeder in <span class="hlt">Chile</span>, nesting only on the Juan Fernandez Archipelago (JFI; 30% of global population), and Isla Mocha (70% of global population). Using miniature GPS and satellite transmitters, we determined foraging areas of Pink-footed Shearwaters during the chick-rearing period in 2002 (JFI) and 2015-2016 (Isla Mocha). We overlaid shearwater tracking data with data from the Instituto de Fomento Pesquero (IFOP) on fishing effort in <span class="hlt">Chile</span> (type of fishery, number sets per day, location of sets, and target species) to identify fisheries and fishing <span class="hlt">zones</span> with the greatest potential for Pink-footed Shearwater bycatch. During the 2002-2006 (N = 28 birds total) and 2015 (N = 18 birds) breeding periods, foraging areas were associated with the continental shelf and shelf-break, generally less than 30 km offshore. All foraging trips occurred between 31.5 and 40.0 degrees south, and birds remained in <span class="hlt">Chile</span> territorial waters 100% of the time. We identified two primary foraging hotspots, one offshore near Talcahuano, <span class="hlt">Chile</span> (approximately 36-37.5° south), and one offshore north of Valdivia, <span class="hlt">Chile</span> (approximately 39-39.5° south). Birds tracked from the Juan Fernández Archipelago foraged in the Talcahuano hotspot but did not visit the southerly hotspot near Valdivia. Birds tracked from Isla Mocha used both areas, with a greater proportion of birds using the Valdivia hotspot than the Talcahuano hotspot. Other major areas of use were around the respective breeding colonies from which the birds were tracked. Overlay of these data with fisheries data is currently in progress. Preliminary results indicate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.H33E1687S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.H33E1687S"><span>Multiple Sulfate Isotopic Evidence on the Formation of Oxide Copper Ore at Spence, Atacama Desert, Northern <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, T.; Bao, H.; Reich, M.; Palacios, C.</p> <p>2007-12-01</p> <p>In the Atacama Desert of northern <span class="hlt">Chile</span>, one of the world's richest metallogenic provinces, porphyry copper deposits are characterized by the unique occurrence of atacamite in their oxidized <span class="hlt">zones</span>. The origin and formation of the oxide <span class="hlt">zone</span> of these copper deposits is, however, controversial. It was proposed that Cl-rich deep formation water pumping-up events along faults by earthquakes, after onset of the hyperaridity, were required (Cameron et al., 2007). Their model would imply that supplies of saline deep formation water from fractures to the surface should have left behind a homogeneous or fracture-controlled salt profile from surface down to the oxide <span class="hlt">zone</span>. While no excluding the deep formation water model in other deposit, here we propose that, in our sampling region, the alternative saline source, which is critical for atacamite formation, could be locally evaporated groundwater, Cl-rich salts leached from arid surface by meteoric water, or brines from eastern salar basins at a time when the climate in northern <span class="hlt">Chile</span> was changing from arid to hyperarid. At this climate transition, arid- requiring minerals such as atacamite in the oxide <span class="hlt">zone</span> were formed and, more importantly, preserved upon evaporation beneath the surface alluvial deposits. Since salt accumulation at the surface remain active during hyperarid condition, our model would predict that water-soluble salt profile from surface to the oxide <span class="hlt">zone</span> should have a characteristic pattern: salts with an atmospheric component on the surface gradually transitioning to salts of the oxide ore <span class="hlt">zone</span> on the bottom and a mixing <span class="hlt">zone</span> in between. To test these two alternative models, we focus on sulfate salts, one of the common water-soluble salts in arid environments. An added advantage is that sulfate accumulated on desert surface has a secondary atmospheric component that bears a unique triple oxygen isotope signature, easily distinguishable from sulfate formed by the oxidation of sulfide minerals at the oxide</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Tectp.677...88K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Tectp.677...88K"><span>Seismic properties of lawsonite eclogites from the <span class="hlt">southern</span> Motagua fault <span class="hlt">zone</span>, Guatemala</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Daeyeong; Wallis, Simon; Endo, Shunsuke; Ree, Jin-Han</p> <p>2016-05-01</p> <p>We present new data on the crystal preferred orientation (CPO) and seismic properties of omphacite and lawsonite in extremely fresh eclogite from the <span class="hlt">southern</span> Motagua fault <span class="hlt">zone</span>, Guatemala, to discuss the seismic anisotropy of subducting oceanic crust. The CPO of omphacite is characterized by (010)[001], and it shows P-wave seismic anisotropies (AVP) of 1.4%-3.2% and S-wave seismic anisotropies (AVS) of 1.4%-2.7%. Lawsonite exhibits (001) planes parallel to the foliation and [010] axes parallel to the lineation, and seismic anisotropies of 1.7%-6.6% AVP and 3.4%-14.7% AVS. The seismic anisotropy of a rock mass consisting solely of omphacite and lawsonite is 1.2%-4.1% AVP and 1.8%-6.8% AVS. For events that propagate more or less parallel to the maximum extension direction, X, the fast S-wave velocity (VS) polarization is parallel to the Z in the Y-Z section (rotated from the X-Z section), causing trench-normal seismic anisotropy for orthogonal subduction. Based on the high modal abundance and strong fabric of lawsonite, the AVS of eclogites is estimated as ~ 11.7% in the case that lawsonite makes up ~ 75% of the rock mass. On this basis, we suggest that lawsonite in both blueschist and eclogite may play important roles in the formation of complex pattern of seismic anisotropy observed in NE Japan: weak trench-parallel anisotropy in the forearc basin domains and trench-normal anisotropy in the backarc region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA516492','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA516492"><span><span class="hlt">Chile</span>: Political and Economic Conditions and U.S. Relations</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2010-03-02</p> <p>until 1818. By 1932, <span class="hlt">Chile</span> had established a mass electoral democracy, which endured until 1973. During much of this period, <span class="hlt">Chile</span> was governed by...served as “senators-for-life” and nine senators were designated by the armed forces and other bodies. 14 Peter M. Siavelis, “ Electoral System...Course in Democracy,” Washington Post , November 25, 2006. 24 “<span class="hlt">Chile</span>: Pinochet-era Education Law Finally Replaced,” Latin News Weekly Report, August 20</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70122660','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70122660"><span>Influence of climate on deep-water clastic sedimentation: application of a modern model, Peru-<span class="hlt">Chile</span> Trough, to an ancient system, Ouachita Trough</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Edgar, N. Terence; Cecil, C. Blaine</p> <p>2003-01-01</p> <p>Traditionally, an abrupt and massive influx of siliciclastic sediments into an area of deposition has been attributed to tectonic uplift without consideration of the influence of climate or climatic change on rates of weathering, erosion, transportation, and deposition. With few exceptions, fluvial sediment transport is minimal in both extremely arid climates and in perhumid (everwet) climates. Maximum sediment transport occurs in climates characterized by strongly seasonal rainfall, where the effect of vegetation on erosion is minimal. The Peru–<span class="hlt">Chile</span> trench and Andes Mountain system (P–CT/AMS) of the eastern Pacific Ocean clearly illustrates the effects of climate on rates of weathering, erosion, transport, and deep-sea sedimentation. Terrigenous sediment is virtually absent in the arid belt north of lat. 30° S in the P–CT, but in the belt of seasonal rainfall south of lat. 30° S terrigenous sediment is abundant. Spatial variations in the amount and seasonality of annual precipitation are now generally accepted as the cause for this difference. The spatial variation in sediment supply to the P–CT appears to be an excellent modern analogue for the temporal variation in sediment supply to certain ancient systems, such as the Ouachita Trough in the <span class="hlt">southern</span> United States. By comparison, during the Ordovician through the early Mississippian, sediment was deposited at very slow rates as the Ouachita Trough moved northward through the <span class="hlt">southern</span> hemisphere dry belt (lat. 10° S to lat. 30° S). The deposystem approached the tropical humid <span class="hlt">zone</span> during the Mississippian, coincident with increased coarse clastic sedimentation. By the Middle Pennsylvanian (Atokan), the provenance area and the deposystem moved well into the tropical humid <span class="hlt">zone</span>, and as much as 8,500 m of mineralogically mature (but texturally immature) quartz sand was introduced and deposited. This increase in clastic sediment deposition traditionally has been attributed solely to tectonic activity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS41C1975W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS41C1975W"><span>Structural features related to the volcanic gases in <span class="hlt">Southern</span> Okinawa Trough</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, H. F.; Hsu, S. K.; Tsia, C. H.; Chen, S. C.; Wu, M. F.</p> <p>2016-12-01</p> <p>The Okinawa Trough is a rifted back-arc basin, heavily sedimented and formed in an intracontinental rift <span class="hlt">zone</span> behind the Ryukyu trench-arc system. The <span class="hlt">Southern</span> Okinawa Trough (SOT) east of Taiwan is the place where post-collisional extension happened. The collision moved southwestward and the Ryukyu trench-arc extension westward, Arc volcanism is dominant in the Northern Ryukyu volcanic arc and back-arc volcanism in the <span class="hlt">Southern</span> Okinawa Trough. Marine geophysical data including side-scan sonar (SSS), sub-bottom profiler (SBP) and echo sounder system (EK60) data are used in this study. Active fluid activities out of seafloor are obvious from various images observed on these data, such as gas plumes. These hydrothermal vents have been located at a water depth of 1400 m. Our preliminary results show that gas seepage structures appear in the location where is a week <span class="hlt">zone</span>, such as a normal fault in the slope. The hydrothermal activity within the Okinawa Trough is associated with volcanism located in rift <span class="hlt">zones</span> in the <span class="hlt">Southern</span> Okinawa Trough. However, the origin of the submarine hydrothermal fluids within the Okinawa Trough is diverse with contributions from volcanic, sedimentary and magmatic sources, needed further investigations.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..44.5374F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..44.5374F"><span>Mapping the rheology of the Central <span class="hlt">Chile</span> subduction <span class="hlt">zone</span> with aftershocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Frank, William B.; Poli, Piero; Perfettini, Hugo</p> <p>2017-06-01</p> <p>The postseismic deformation following a large (Mw >7) earthquake is expressed both seismically and aseismically. Recent studies have appealed to a model that suggests that the aseismic slip on the plate interface following the mainshock can be the driving factor in aftershock sequences, reproducing both the geodetic (afterslip) and seismic (aftershocks) observables of postseismic deformation. Exploiting this model, we demonstrate how a dense catalog of aftershocks following the 2015 Mw 8.3 Illapel earthquake in Central <span class="hlt">Chile</span> can constrain the frictional and rheological properties of the creeping regions of the subduction interface. We first expand the aftershock catalog via a 19 month continuous matched-filter search and highlight the log-time expansion of seismicity following the mainshock, suggestive of afterslip as the main driver of aftershock activity. We then show how the time history of aftershocks can constrain the temporal evolution of afterslip. Finally, we use our dense aftershock catalog to estimate the rate and state rheological parameter (a - b)σ as a function of depth and demonstrate that this low value is compatible either with a nearly velocity-neutral friction (a≈b) in the regions of the megathrust that host afterslip, or an elevated pore fluid pressure (low effective normal stress σ) along the plate interface. Our results present the first snapshot of rheology in depth together with the evolution of the tectonic stressing rate along a plate boundary. The framework described here can be generalized to any tectonic context and provides a novel way to constrain the frictional properties and loading conditions of active faults.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25338112','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25338112"><span>Rocky intertidal zonation pattern in Antofagasta, <span class="hlt">chile</span>: invasive species and shellfish gathering.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Castilla, Juan Carlos; Manríquez, Patricio H; Delgado, Alejandro; Ortiz, Verónica; Jara, María Elisa; Varas, Manuel</p> <p>2014-01-01</p> <p>Biological invasions affecting rocky intertidal zonation patterns, yield information on species interactions. In the Bay of Antofagasta, northern <span class="hlt">Chile</span>, the non-indigenous tunicate Pyura praeputialis, originally from Australia, has invaded (in the past century or so) and monopolized a major portion of the mid-intertidal rocky shore, displacing upshore the native mussel Perumytilus purpuratus. In Antofagasta the tunicate is subjected to intensive exploitation. Monitoring protocols show that in the past 10 years Antofagasta's tunicate population has experienced a drastic decline, affecting the intertidal zonation pattern. A 12.5 km of coastline, on the <span class="hlt">southern</span> eastern shore of the Bay of Antofagasta, was studied. Eight sites were systematically (1993-1994) or sporadically (2003-2014) monitored for the seaward-shoreward expansion or reduction of the tunicate Pyura praeputialis, and native mussel and barnacle bands. A notable reduction in the mid-intertidal band of P. praeputialis and a seaward expansion of the mussel, Perumytilus purpuratus, and barnacle bands was observed. We suggest that the major cause for the decline in the tunicate is due to its intensive exploitation by rocky shore Pyura-gathers. The rate of extraction of tunicates by professional Pyura-gathers ranged between 256-740 tunicates hour-(1). Between 2009-2014 the density of professional Pyura-gather ranged between 0.5-4.5 km(-1) per low tide. Hence, 10 professional Pyura-gathers working 1 h for 10 low tides per month, during 6 months, will remove between 307-888 m(2) of tunicates. A drastic decline in tunicate recruitment was observed and several P. praeputialis ecosystems services have been lost. In Antofagasta, the continuous and intensive intertidal gathering of the invasive tunicate Pyura praeputialis, has caused a drastic reduction of its population modifying the zonation pattern. Thereby, native mussel Perumytilus purpuratus has regained its ecological center in the intertidal <span class="hlt">zone</span>. We</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S51A0582R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S51A0582R"><span>Nucleation process and dynamic inversion of the Mw 6.9 Valparaíso 2017 earthquake in Central <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruiz, S.; Aden-Antoniow, F.; Baez, J. C., Sr.; Otarola, C., Sr.; Potin, B.; DelCampo, F., Sr.; Poli, P.; Flores, C.; Satriano, C.; Felipe, L., Sr.; Madariaga, R. I.</p> <p>2017-12-01</p> <p>The Valparaiso 2017 sequence occurred in mega-thrust Central <span class="hlt">Chile</span>, an active <span class="hlt">zone</span> where the last mega-earthquake occurred in 1730. An intense seismicity occurred 2 days before of the Mw 6.9 main-shock. A slow trench ward movement observed in the coastal GPS antennas accompanied the foreshock seismicity. Following the Mw 6.9 earthquake the seismicity migrated 30 Km to South-East. This sequence was well recorded by multi-parametric stations composed by GPS, Broad-Band and Strong Motion instruments. We built a seismic catalogue with 2329 events associated to Valparaiso sequence, with a magnitude completeness of Ml 2.8. We located all the seismicity considering a new 3D velocity model obtained for the Valparaiso <span class="hlt">zone</span>, and compute the moment tensor for events with magnitude larger than Ml 3.5, and finally studied the presence of repeating earthquakes. The main-shock is studied by performing a dynamic inversion using the strong motion records and an elliptical patch approach to characterize the rupture process. During the two days nucleation stage, we observe a compact <span class="hlt">zone</span> of repeater events. In the meantime a westward GPS movement was recorded in the coastal GPS stations. The aseismic moment estimated from GPS is larger than the foreshocks cumulative moment, suggesting the presence of a slow slip event, which potentially triggered the 6.9 mainshock. The Mw 6.9 earthquake is associated to rupture of an elliptical asperity of semi-axis of 10 km and 5 km, with a sub-shear rupture, stress drop of 11.71 MPa, yield stress of 17.21 MPa, slip weakening of 0.65 m and kappa value of 1.70. This sequence occurs close to, and with some similar characteristics that 1985 Valparaíso Mw 8.0 earthquake. The rupture of this asperity could stress more the highly locked Central <span class="hlt">Chile</span> <span class="hlt">zone</span> where a mega-thrust earthquake like 1730 is expected.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28616174','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28616174"><span>Spatial overlap of shark nursery areas and the salmon farming industry influences the trophic ecology of Squalus acanthias on the <span class="hlt">southern</span> coast of <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gaitán-Espitia, Juan Diego; Gómez, Daniela; Hobday, Alistair J; Daley, Ross; Lamilla, Julio; Cárdenas, Leyla</p> <p>2017-06-01</p> <p>Potential interactions between marine predators and humans arise in the <span class="hlt">southern</span> coast of <span class="hlt">Chile</span> where predator feeding and reproduction sites overlap with fisheries and aquaculture. Here, we assess the potential effects of intensive salmon aquaculture on food habits, growth, and reproduction of a common predator, the spiny dogfish-identified as Squalus acanthias via genetic barcoding. A total of 102 (89 females and 13 males) individuals were collected during winter and summer of 2013-2014 from the Chiloé Sea where salmon aquaculture activities are concentrated. The low frequency of males in our study suggests spatial segregation of sex, while immature and mature females spatially overlapped in both seasons. Female spiny dogfish showed a functional specialist behavior as indicated by the small number of prey items and the relative high importance of the austral hake and salmon pellets in the diet. Immature sharks fed more on pellets and anchovies than the larger hake-preferring mature females. Our results also indicate that spiny dogfish switch prey (anchovy to hake) to take advantage of seasonal changes in prey availability. Despite differences in the trophic patterns of S. acanthias due to the spatial association with intensive salmon farming, in this region, there appears to be no difference in fecundity or size at maturity compared to other populations. Although no demographic effects were detected, we suggest that a range of additional factors should be considered before concluding that intensive aquaculture does not have any impact on these marine predators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4451210','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4451210"><span>Spatio-Temporal Analysis of Smear-Positive Tuberculosis in the Sidama <span class="hlt">Zone</span>, <span class="hlt">Southern</span> Ethiopia</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dangisso, Mesay Hailu; Datiko, Daniel Gemechu; Lindtjørn, Bernt</p> <p>2015-01-01</p> <p>Background Tuberculosis (TB) is a disease of public health concern, with a varying distribution across settings depending on socio-economic status, HIV burden, availability and performance of the health system. Ethiopia is a country with a high burden of TB, with regional variations in TB case notification rates (CNRs). However, TB program reports are often compiled and reported at higher administrative units that do not show the burden at lower units, so there is limited information about the spatial distribution of the disease. We therefore aim to assess the spatial distribution and presence of the spatio-temporal clustering of the disease in different geographic settings over 10 years in the Sidama <span class="hlt">Zone</span> in <span class="hlt">southern</span> Ethiopia. Methods A retrospective space–time and spatial analysis were carried out at the kebele level (the lowest administrative unit within a district) to identify spatial and space-time clusters of smear-positive pulmonary TB (PTB). Scan statistics, Global Moran’s I, and Getis and Ordi (Gi*) statistics were all used to help analyze the spatial distribution and clusters of the disease across settings. Results A total of 22,545 smear-positive PTB cases notified over 10 years were used for spatial analysis. In a purely spatial analysis, we identified the most likely cluster of smear-positive PTB in 192 kebeles in eight districts (RR= 2, p<0.001), with 12,155 observed and 8,668 expected cases. The Gi* statistic also identified the clusters in the same areas, and the spatial clusters showed stability in most areas in each year during the study period. The space-time analysis also detected the most likely cluster in 193 kebeles in the same eight districts (RR= 1.92, p<0.001), with 7,584 observed and 4,738 expected cases in 2003-2012. Conclusion The study found variations in CNRs and significant spatio-temporal clusters of smear-positive PTB in the Sidama <span class="hlt">Zone</span>. The findings can be used to guide TB control programs to devise effective TB control</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA183905','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA183905"><span>Studies to Control Endemic Typhoid Fever in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1985-09-01</p> <p>Society for Microbiology, Chapter 16. 10. Medina E, Yrarrazaval M. (1983) Fiebre tifoidea en <span class="hlt">Chile</span>: Consideraciones epideniologicas. Revista Medica de...epidesiologia de la fiebre tifoidea . Boletin de !a Escuela de Medicina, Pontificia universidad catolica de <span class="hlt">Chile</span>. 30:113-119. 14. Reyes H, Olea M, Hernandez</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70188393','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70188393"><span>Origin of the Blytheville Arch, and long-term displacement on the New Madrid seismic <span class="hlt">zone</span>, central United States</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Pratt, Thomas L.; Williams, Robert; Odum, Jackson K.; Stephenson, William J.</p> <p>2013-01-01</p> <p>The <span class="hlt">southern</span> arm of the New Madrid seismic <span class="hlt">zone</span> of the central United States coincides with the buried, ~110 km by ~20 km Blytheville Arch antiform within the Cambrian–Ordovician Reelfoot rift graben. The Blytheville Arch has been interpreted at various times as a compressive structure, an igneous intrusion, or a sediment diapir. Reprocessed industry seismic-reflection profiles presented here show a strong similarity between the Blytheville Arch and pop-up structures, or flower structures, within strike-slip fault systems. The Blytheville Arch formed in the Paleozoic, but post–Mid-Cretaceous to Quaternary strata show displacement or folding indicative of faulting. Faults within the graben structure but outside of the Blytheville Arch also appear to displace Upper Cretaceous and perhaps younger strata, indicating that past faulting was not restricted to the Blytheville Arch and New Madrid seismic <span class="hlt">zone</span>. As much as 10–12.5 km of strike slip can be estimated from apparent shearing of the Reelfoot arm of the New Madrid seismic <span class="hlt">zone</span>. There also appears to be ~5–5.5 km of shearing of the Reelfoot topographic scarp at the north end of the <span class="hlt">southern</span> arm of the New Madrid seismic <span class="hlt">zone</span> and of the <span class="hlt">southern</span> portion of Crowley's Ridge, which is a north-trending topographic ridge just south of the seismic <span class="hlt">zone</span>. These observations suggest that there has been substantial strike-slip displacement along the Blytheville Arch and <span class="hlt">southern</span> arm of the New Madrid seismic <span class="hlt">zone</span>, that strike-slip extended north and south of the modern seismic <span class="hlt">zone</span>, and that post–Mid-Cretaceous (post-Eocene?) faulting was not restricted to the Blytheville Arch or to currently active faults within the New Madrid seismic <span class="hlt">zone</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24265726','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24265726"><span>Unveiling current Guanaco distribution in <span class="hlt">chile</span> based upon niche structure of phylogeographic lineages: Andean puna to subpolar forests.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>González, Benito A; Samaniego, Horacio; Marín, Juan Carlos; Estades, Cristián F</p> <p>2013-01-01</p> <p>Niche description and differentiation at broad geographic scales have been recent major topics in ecology and evolution. Describing the environmental niche structure of sister taxa with known evolutionary trajectories stands out as a useful exercise in understanding niche requirements. Here we model the environmental niche structure and distribution of the recently resolved phylogeography of guanaco (Lama guanicoe) lineages on the western slope of the <span class="hlt">southern</span> Andes. Using a maximum entropy framework, field data, and information on climate, topography, human density, and vegetation cover, we identify differences between the two subspecies (L.g.cacsilensis, L.g.guanicoe) and their intermediate-hybrid lineage, that most likely determine the distribution of this species. While aridity seems to be a major factor influencing the distribution at the species-level (annual precipitation <900 mm), we also document important differences in niche specificity for each subspecies, where distribution of Northern lineage is explained mainly by elevation (mean = 3,413 m) and precipitation seasonality (mean = 161 mm), hybrid lineage by annual precipitation (mean = 139 mm), and <span class="hlt">Southern</span> subspecies by annual precipitation (mean = 553 mm), precipitation seasonality (mean = 21 mm) and grass cover (mean = 8.2%). Among lineages, we detected low levels of niche overlap: I (Similarity Index) = 0.06 and D (Schoener's Similarity Index) = 0.01; and higher levels when comparing Northern and <span class="hlt">Southern</span> subspecies with hybrids lineage ( I = 0.32-0.10 and D = 0.12-0.03, respectively). This suggests that important ecological and/or evolutionary processes are shaping the niche of guanacos in <span class="hlt">Chile</span>, producing discrepancies when comparing range distribution at the species-level (81,756 km(2)) with lineages-level (65,321 km(2)). The subspecies-specific description of niche structure is provided here based upon detailed spatial distribution of the lineages of guanacos in <span class="hlt">Chile</span>. Such description provides</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2010-01-22/pdf/2010-1136.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2010-01-22/pdf/2010-1136.pdf"><span>75 FR 3756 - Preserved Mushrooms from <span class="hlt">Chile</span>, China, India, and Indonesia</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2010-01-22</p> <p>...)] Preserved Mushrooms from <span class="hlt">Chile</span>, China, India, and Indonesia AGENCY: United States International Trade... preserved mushrooms from <span class="hlt">Chile</span>, China, India, and Indonesia. SUMMARY: The Commission hereby gives notice of... mushrooms from <span class="hlt">Chile</span>, China, India, and Indonesia would be likely to lead to continuation or recurrence of...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.A11B0119V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.A11B0119V"><span>Atmospheric Concentrations of Persistent Organic Pollutants in the <span class="hlt">Southern</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vlahos, P.; Edson, J.; Cifuentes, A.; McGillis, W. R.; Zappa, C.</p> <p>2008-12-01</p> <p>Long-range transport of persistent organic pollutant (POPs) is a global concern. Remote regions such as the <span class="hlt">Southern</span> Ocean are greatly under-sampled though critical components in understanding POPs cycling. Over 20 high-volume air samples were collected in the <span class="hlt">Southern</span> Ocean aboard the RV Brown during the GASEX III experiment between Mar 05 to April 9 2008. The relatively stationary platform (51S,38W) enabled the collection of a unique atmospheric time series at this open ocean station. Air sampling was also conducted across transects from Punto Arenas, <span class="hlt">Chile</span> and to Montevideo, Uruguay. Samples were collected using glass sleeves packed with poly-urethane foam plugs and C-18 resin in order to collect target organic pollutants (per-fluorinated compounds, currently and historically used pesticides) in this under-sampled region. Here we present POPs concentrations and trends over the sampled period and compare variations with air parcel back trajectories to establish potential origins of their long-range transport.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70019356','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70019356"><span>Tectonics and seismicity of the <span class="hlt">southern</span> Washington Cascade range</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stanley, W.D.; Johnson, S.Y.; Qamar, A.I.; Weaver, C.S.; Williams, J.M.</p> <p>1996-01-01</p> <p>Geophysical, geological, and seismicity data are combined to develop a transpressional strain model for the <span class="hlt">southern</span> Washington Cascades region. We use this model to explain oblique fold and fault systems, transverse faults, and a linear seismic <span class="hlt">zone</span> just west of Mt. Rainier known as the western Rainier <span class="hlt">zone</span>. We also attempt to explain a concentration of earthquakes that connects the northwest-trending Mount St. Helens seismic <span class="hlt">zone</span> to the north-trending western Rainier <span class="hlt">zone</span>. Our tectonic model illustrates the pervasive effects of accretionary processes, combined with subsequent transpressive forces generated by oblique subduction, on Eocene to present crustal processes, such as seismicity and volcanism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.8139L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.8139L"><span>One year after the 1 April 2014 Iquique tsunami field survey along the coasts of <span class="hlt">Chile</span> and Peru</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lagos, Marcelo; Fritz, Hermann M.</p> <p>2015-04-01</p> <p>One year ago on the evening of 1 April, 2014 a magnitude Mw 8.2 earthquake occurred off the coast of northern <span class="hlt">Chile</span> off the coast of Pisagua within a region of historic quiescence termed the northern <span class="hlt">Chile</span> seismic gap. The ensuing tsunami inundation caused mostly minor damage centered in Iquique and neighbouring stretches of coastline. Fortunately, ancestral knowledge from the past 1868 and 1877 tsunamis in the region along with the recent 2010 Maule tsunami, as well as tsunami education and evacuation exercises prompted most coastal residents to spontaneously evacuate to high ground after the earthquake. There were no tsunami victims; while a handful of fatalities were associated to earthquake induced building collapses and the physical stress of tsunami evacuation. The Arica native local scientist deployed overnight and started the tsunami survey in Iquique on the day after the earthquake. The international scientist joined the local effort from April 6 to 11, 2014. The international tsunami survey team (ITST) interviewed numerous eyewitnesses and documented flow depths, runup heights, inundation distances, sediment deposition, damage patterns, performance of the navigation infrastructure and impact on the natural environment. The ITST covered a 700 km stretch of coastline from the Mejillones Peninsula (23.5° S) north of Antofagasta in <span class="hlt">Chile</span> up to Vila Vila (18.1° S) in <span class="hlt">southern</span> Peru. We surveyed 30 locations with differential GPS and laser range finders. The tsunami impact peaked at Caleta Camarones exceeding 5 m in tsunami runup height. A significant variation in tsunami impact was observed along the coastlines of <span class="hlt">Chile</span> and Peru both at local and regional scales. The tsunami occurred in the evening hours limiting the availability of eyewitness video footages. Observations from the 2014 <span class="hlt">Chile</span> tsunami are compared against the 1868, 1877 and 2010 <span class="hlt">Chile</span> tsunamis. Comparing to other similar magnitude events such as the 2007 Pisco tsunami in Peru the 1 April 2014</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110002773','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110002773"><span>Geology of the Terra Cimmeria-Utopia Planitia Highland Lowland Transitional <span class="hlt">Zone</span>: Final Technical Approach and Scientific Results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Skinner, J. A., Jr.; Tanaka, K. L.</p> <p>2010-01-01</p> <p>The <span class="hlt">southern</span> Utopia highland-lowland transitional <span class="hlt">zone</span> extends from northern Terra Cimmeria to <span class="hlt">southern</span> Utopia Planitia and contains broad, bench-like platforms with depressions, pitted cones, tholi, and lobate flows. The locally occurring geologic units and landforms contrast other transitional regions and record a spatially partitioned geologic history. We systematically delineated and described the geologic units and landforms of the <span class="hlt">southern</span> Utopia-Cimmeria highland-lowland transitional <span class="hlt">zone</span> for the production of a 1:1,000,000-scale geologic map (MTMs 10237, 15237, 20237, 10242, 15242, 20242, 10247, 15247, and 20247). Herein, we present technical and scientific results of this mapping project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70012854','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70012854"><span>Origin and distribution of carbon dioxide in the unsaturated <span class="hlt">zone</span> of the <span class="hlt">southern</span> High Plains of Texas</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wood, Warren W.; Petraitis, Michael J.</p> <p>1984-01-01</p> <p>Partial pressures of CO2, O2, N2, and Ar were monitored at two locations in the Ogallala aquifer system on the <span class="hlt">Southern</span> High Plains of Texas. Samples were collected monthly during parts of 1980–1981 from nine depths ranging from 0.6 to 36 meters below land surface. PCO2 was observed to be greater at depth than in the active soil <span class="hlt">zone</span> and thus appears to contradict the normal process in which CO2 is generated in the soil <span class="hlt">zone</span> and diffuses upward to the atmosphere and downward to the water table. The δ13C of the CO2 gas was quite uniform and averaged −17.9 per mil. PO2 declined with depth, suggesting in situ generation of CO2 by the oxidation of carbon. Several hypotheses were considered to explain the origin of the CO2 at depth. It was concluded that the most probable hypothesis was that dissolved and particulate organic carbon introduced by recharging water was oxidized to CO2 by the aerobic microbial community that utilized oxygen diffusing in from the atmosphere. This hypothesis is consistent with the CO2 concentration profile, calculated production profile of CO2, δ13C values of CO2 gas, caliche, soil humic acid fraction, and dissolved carbonate in groundwater. The abundance of CO2, its concentration profile, and its probable origin provide information for evaluating the observed complex sequence of caliche dissolution and precipitation known to occur in the aquifer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29554623','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29554623"><span>Perchlorate contamination in <span class="hlt">Chile</span>: Legacy, challenges, and potential solutions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vega, Marcela; Nerenberg, Robert; Vargas, Ignacio T</p> <p>2018-07-01</p> <p>This paper reviews the unique situation of perchlorate contamination in <span class="hlt">Chile</span>, including its sources, presence in environmental media and in the human population, and possible steps to mitigate its health impacts. Perchlorate is a ubiquitous water contaminant that inhibits thyroid function. Standards for drinking water range from 2 to 18 µg L -1 in United States and Europe. A major natural source of perchlorate contamination is <span class="hlt">Chile</span> saltpeter, found in the Atacama Desert. High concentrations of perchlorate have presumably existed in this region, in soils, sediments, surface waters and groundwaters, for millions of years. As a result of this presence, and the use of <span class="hlt">Chile</span> saltpeter as a nitrogen fertilizer, perchlorate in <span class="hlt">Chile</span> has been found at concentrations as high as 1480 µg L -1 in drinking water, 140 µg/kg -1 in fruits, and 30 µg L -1 in wine. Health studies in <span class="hlt">Chile</span> have shown concentrations of 100 µg L - 1 in breast milk and 20 µg L -1 in neonatal serum. It is important to acknowledge perchlorate as a potential health concern in <span class="hlt">Chile</span>, and assess mitigation strategies. A more thorough survey of perchlorate in Chilean soils, sediments, surface waters, groundwaters, and food products can help better assess the risks and potentially develop standards. Also, perchlorate treatment technologies should be more closely assessed for relevance to <span class="hlt">Chile</span>. The Atacama Desert is a unique biogeochemical environment, with millions of years of perchlorate exposure, which can be mined for novel perchlorate-reducing microorganisms, potentially leading to new biological treatment processes for perchlorate-containing waters, brines, and fertilizers. Copyright © 2018 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=traductor&id=ED273086','ERIC'); return false;" href="https://eric.ed.gov/?q=traductor&id=ED273086"><span>Estudio del campo ocupacional del traductor en Santiago de <span class="hlt">Chile</span> (A Study of Opportunities for Professional Translators in Santiago, <span class="hlt">Chile</span>).</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Cabrera, Ileana; And Others</p> <p></p> <p>A study of translation as a profession in <span class="hlt">Chile</span> covered two areas: a diagnostic study of the real need for literary, scientific, and technical translations, and a followup study of graduates of the translation degree program at the Catholic Pontifical University of <span class="hlt">Chile</span> (Santiago). The analysis considered the relationship between the need for…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006JMS....62..152M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006JMS....62..152M"><span>Sediment profile imaging (SPI) and micro-electrode technologies in impact assessment studies: Example from two fjords in <span class="hlt">Southern</span> <span class="hlt">Chile</span> used for fish farming</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mulsow, S.; Krieger, Y.; Kennedy, R.</p> <p>2006-10-01</p> <p>Two state-of-the-art techniques were used to assess the impact of organic loading from fish farming in two fjords of <span class="hlt">Southern</span> <span class="hlt">Chile</span>, Pillan and Reñihue Fjords. A sediment profile imaging (SPI) camera was deployed and sediment microprofiles (oxygen, H 2S, redox and pH) were measured in undisturbed sediment cores collected using a HAPS corer. Four out of seven stations in Pillan Fjord were found to be severely disturbed: SPI images showed azoic conditions (no apparent Redox Potential Discontinuity layer, no evidence of aerobic life form, presence of an uneaten fish food layer, negative OSI scores). These findings were corroborated by very high oxygen consumption rates (700-1200 mmol m - 2 day - 1 ), H 2S concentrations increasing quickly within the sediment column and redox potential decreasing towards negative values within a few mm down core. Results for Reñihue Fjord were not so straightforward. SPI images indicated that most of the stations (R3 to R7) presented well-mixed conditions (high apparent RPD layers, presence of infauna, burrows, etc.), but oxygen profiles yielded consumption rates of 230 to 490 mmol m - 2 day - 1 and organic carbon mineralization of 2.16 to 4.53 g C m - 2 day - 1 . These latter values were close to the limit of aerobic degradation of organic matter although no visible changes were recorded within the sediment column. In view of our findings, the importance of integrating multidisciplinary methodologies in impact assessment studies was discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA256883','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA256883"><span>The Death of Socialism in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1992-06-05</p> <p>Frank S. Smallwood, M.A. •. Member Accepted this 5th day of June 1992 by: 9 4-A1 %/ Director, Graduate Philip J . Brookes, Ph.D. Degree Programs The...P. 2. 2 Jorge Palacios, <span class="hlt">CHILE</span>: An Attempt at "Historic Compromise". (Chicago: Banner Press, 1979), p. 79. 3 David J . Bowen, The Land and People of...Washington, D. C. American University Press, 1982), p. 35. 6 Robert J . Alexander, The Tragedy of <span class="hlt">Chile</span>. (London: Greenwood Press, 1978), p. 314. CHAPTER</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3142489','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3142489"><span>The high Andes, gene flow and a stable hybrid <span class="hlt">zone</span> shape the genetic structure of a wide-ranging South American parrot</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2011-01-01</p> <p>Background While the gene flow in some organisms is strongly affected by physical barriers and geographical distance, other highly mobile species are able to overcome such constraints. In <span class="hlt">southern</span> South America, the Andes (here up to 6,900 m) may constitute a formidable barrier to dispersal. In addition, this region was affected by cycles of intercalating arid/moist periods during the Upper/Late Pleistocene and Holocene. These factors may have been crucial in driving the phylogeographic structure of the vertebrate fauna of the region. Here we test these hypotheses in the burrowing parrot Cyanoliseus patagonus (Aves, Psittaciformes) across its wide distributional range in <span class="hlt">Chile</span> and Argentina. Results Our data show a Chilean origin for this species, with a single migration event across the Andes during the Upper/Late Pleistocene, which gave rise to all extant Argentinean mitochondrial lineages. Analyses suggest a complex population structure for burrowing parrots in Argentina, which includes a hybrid <span class="hlt">zone</span> that has remained stable for several thousand years. Within this <span class="hlt">zone</span>, introgression by expanding haplotypes has resulted in the evolution of an intermediate phenotype. Multivariate regressions show that present day climatic variables have a strong influence on the distribution of genetic heterogeneity, accounting for almost half of the variation in the data. Conclusions Here we show how huge barriers like the Andes and the regional environmental conditions imposed constraints on the ability of a parrot species to colonise new habitats, affecting the way in which populations diverged and thus, genetic structure. When contact between divergent populations was re-established, a stable hybrid <span class="hlt">zone</span> was formed, functioning as a channel for genetic exchange between populations. PMID:21672266</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JSG....35...17K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JSG....35...17K"><span>Quantitative kinematic analysis within the Khlong Marui shear <span class="hlt">zone</span>, <span class="hlt">southern</span> Thailand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanjanapayont, Pitsanupong; Grasemann, Bernhard; Edwards, Michael A.; Fritz, Harald</p> <p>2012-02-01</p> <p>The NNE trending Khlong Marui shear <span class="hlt">zone</span> has a strong geomorphic signal with marked fault-strike parallel topographic ridges. The lithologies within the strike-slip <span class="hlt">zone</span> mainly consist of vertical layers of mylonitic meta-sedimentary rocks associated with orthogneisses, mylonitic granites, and pegmatitic veins. The pegmatitic veins concordantly intrude the mylonitic foliation but were sheared at the rims indicating syn-kinematic emplacement. Microstructures and mineral assemblages suggest that the rocks in the area have been metamorphosed at amphibolite facies and low to medium greenschist facies by the first deformation. The Khlong Marui shear <span class="hlt">zone</span> was deformed under dextral simple shear flow with a small finite strain. The ductile-to-brittle deformation involves a period of exhumation of lenses of higher grade rocks together with low grade fault rocks probably associated with positive flower structures. The final stage brittle deformation is reflected by normal faulting and formation of proto-cataclasites to cataclasites of the original mylonitic meta-sedimentary host rock. Although clear age-constraints are still missing, we use regional relationships to speculate that earlier dextral strike-slip displacement of the Khlong Marui shear <span class="hlt">zone</span> was related to the West Burma and Shan-Thai collision and subduction along the Sunda Trench in the Late Cretaceous, while the major exhumation period of the ductile lens was tectonically influenced by the early India-Asia collision. The changing stress field has responded by switching from dextral strike-slip to normal faulting in the Khlong Marui shear <span class="hlt">zone</span>, and is associated with "escape tectonics" arising from the overall India-Asia collision.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006DSRI...53.1203H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006DSRI...53.1203H"><span>The seasonal succession of zooplankton in the <span class="hlt">Southern</span> Ocean south of Australia, part II: The Sub-Antarctic to Polar Frontal <span class="hlt">Zones</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hunt, Brian P. V.; Hosie, Graham W.</p> <p>2006-07-01</p> <p>Between October 2001 and March 2002 six transects were completed at monthly intervals in the Sub-Antarctic <span class="hlt">Zone</span> (SAZ) and Inter-Sub-Antarctic Front <span class="hlt">Zone</span> (ISAFZ)/Polar Frontal <span class="hlt">Zone</span> (PFZ) in the <span class="hlt">Southern</span> Ocean south of Australia. Zooplankton were collected with a Continuous Plankton Recorder and NORPAC net and multivariate analysis was used to analyse the seasonal succession of communities. Despite strong, seasonally consistent, biogeographic differences between the SAZ and ISAFZ/PFZ, community structure in all <span class="hlt">zones</span> was dominated by a suite of common taxa. These included the ubiquitous Oithona similis, foraminiferans and appendicularians (Core taxa), occurring in >97% of samples and contributing an average of 75% to total sample abundance, and Calanus simillimus, Rhincalanus gigas, Ctenocalanus citer, Clausocalanus brevipes, Clausocalanus laticeps, Oithona frigida, Limacina spp. and chaetognaths (Summer taxa), present in >57% of samples and occurring at seasonally high densities. Because of the dominance of the Core and Summer taxa, the seasonal succession was most clearly evident as a change in zooplankton densities. In October densities averaged <15 ind m -3, rising to 52 ind m -3 (max=92 ind m -3) in November, and subsequently increasing slowly through to January (ave=115 ind m -3; max=255 ind m -3). Densities peaked abruptly in February (ave=634 ind m -3; max=1593 ind m -3), and remained relatively high in March (ave=193 ind m -3; max=789 ind m -3). A latitudinal lag in seasonal development was observed with peak densities occurring first in the SAZ (February) and then in the ISAFZ/PFZ (March). The seasonal community succession was strongly influenced by species population cycles. The role of zooplankton in biogeochemical cycling in the SAZ and ISAFZ/PFZ was discussed in the light of past sediment trap data collected from the study area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19083117','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19083117"><span>Communal goat production in <span class="hlt">Southern</span> Africa: a review.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rumosa Gwaze, F; Chimonyo, M; Dzama, K</p> <p>2009-10-01</p> <p>Despite the fact that about 64% of goats in sub-Saharan Africa (SSA) are located in rural arid (38%) and semi-arid (26%) agro-ecological <span class="hlt">zones</span> and that more than 90% of goats in these <span class="hlt">zones</span> are indigenous, information on indigenous breeds is inadequate. This paper reviews the social and economic importance of goats to the communal farmer and assesses the potential of using goats in rural development in <span class="hlt">Southern</span> Africa. Farmers in <span class="hlt">Southern</span> Africa largely use the village goat management system. There are various goat breeds in <span class="hlt">Southern</span> Africa, of which the Mashona, Matabele, Tswana, Nguni and the Landim are the dominant ones. It is, however, not clear if these breeds are distinct. Major constraints to goat production include high disease and parasite prevalence, low levels of management, limited forage availability and poor marketing management. Potential research areas that are required to ensure that goats are vehicles for rural development include evaluation of constraints to goat production, assessing the contribution of goats to household economies and food securities throughout the year, genetic and phenotypic characterisation of the indigenous breeds to identify appropriate strains and sustainable methods of goat improvement through either selection or crossbreeding.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA173510','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA173510"><span>The Revolutionary Left and Terrorist Violence in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1986-06-01</p> <p>Fraude Electoral Designada por la Facultad de Derecho de la Pontifica Universidad de <span class="hlt">Chile</span>," in Libro Blanco del Cambio de Gobierno de <span class="hlt">Chile</span>, Editorial...Chilean law, could not be invaded by the police. The MIR never became a formal political party. It completely rejected the electoral process</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25263288','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25263288"><span>Not all fish are equal: functional biodiversity of cartilaginous fishes (Elasmobranchii and Holocephali) in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bustamante, C; Vargas-Caro, C; Bennett, M B</p> <p>2014-11-01</p> <p>A review of the primary literature on the cartilaginous fishes (sharks, skates, rays and chimaeras), together with new information suggests that 106 species occur in Chilean waters, comprising 58 sharks, 30 skates, 13 rays and five chimaeras. The presence of 93 species was confirmed, although 30 species were encountered rarely, through validated catch records and sightings made in artisanal and commercial fisheries and on specific research cruises. Overall, only 63 species appear to have a range distribution that normally includes Chilean waters. Actual reliable records of occurrence are lacking for 13 species. <span class="hlt">Chile</span> has a cartilaginous fish fauna that is relatively impoverished compared with the global species inventory, but conservative compared with countries in South America with warm-temperate waters. The region of highest species richness occurs in the mid-Chilean latitudes of c. 30-40° S. This region represents a transition <span class="hlt">zone</span> with a mix of species related to both the warm-temperate Peruvian province to the north and cold-temperate Magellan province to the south. This study provides clarification of species occurrence and the functional biodiversity of <span class="hlt">Chile</span>'s cartilaginous fish fauna. © 2014 The Fisheries Society of the British Isles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1437/l/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1437/l/"><span>Cascadia Subduction <span class="hlt">Zone</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Frankel, Arthur D.; Petersen, Mark D.</p> <p>2008-01-01</p> <p>The geometry and recurrence times of large earthquakes associated with the Cascadia Subduction <span class="hlt">Zone</span> (CSZ) were discussed and debated at a March 28-29, 2006 Pacific Northwest workshop for the USGS National Seismic Hazard Maps. The CSZ is modeled from Cape Mendocino in California to Vancouver Island in British Columbia. We include the same geometry and weighting scheme as was used in the 2002 model (Frankel and others, 2002) based on thermal constraints (Fig. 1; Fluck and others, 1997 and a reexamination by Wang et al., 2003, Fig. 11, eastern edge of intermediate shading). This scheme includes four possibilities for the lower (eastern) limit of seismic rupture: the base of elastic <span class="hlt">zone</span> (weight 0.1), the base of transition <span class="hlt">zone</span> (weight 0.2), the midpoint of the transition <span class="hlt">zone</span> (weight 0.2), and a model with a long north-south segment at 123.8? W in the <span class="hlt">southern</span> and central portions of the CSZ, with a dogleg to the northwest in the northern portion of the <span class="hlt">zone</span> (weight 0.5). The latter model was derived from the approximate average longitude of the contour of the 30 km depth of the CSZ as modeled by Fluck et al. (1997). A global study of the maximum depth of thrust earthquakes on subduction <span class="hlt">zones</span> by Tichelaar and Ruff (1993) indicated maximum depths of about 40 km for most of the subduction <span class="hlt">zones</span> studied, although the Mexican subduction <span class="hlt">zone</span> had a maximum depth of about 25 km (R. LaForge, pers. comm., 2006). The recent inversion of GPS data by McCaffrey et al. (2007) shows a significant amount of coupling (a coupling factor of 0.2-0.3) as far east as 123.8? West in some portions of the CSZ. Both of these lines of evidence lend support to the model with a north-south segment at 123.8? W.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SedG..253....1O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SedG..253....1O"><span>The Miocene Nullarbor Limestone, <span class="hlt">southern</span> Australia; deposition on a vast subtropical epeiric platform</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>O'Connell, Laura G.; James, Noel P.; Bone, Yvonne</p> <p>2012-05-01</p> <p>The early to middle Miocene Nullarbor Limestone forms the vast, karsted Nullarbor Plain in <span class="hlt">southern</span> Australia, and may be the most extensive Miocene carbonate deposit described to date. These carbonates were deposited at <span class="hlt">southern</span> paleolatitudes of ~ 40°S and are interpreted to be subtropical to warm-temperate in character because of the presence of certain genera of tropical coralline algae (rhodoliths and articulated types), large benthic foraminifera, tropical molluscs, zooxanthellate corals, and micrite envelopes. Facies are dominated by skeletal grainstones and floatstones that accumulated in three interpreted paleoenvironments: (1) seagrass banks (upper photic <span class="hlt">zone</span>), (2) rhodolith pavements (lower photic <span class="hlt">zone</span>), and (3) open seafloors (lower photic to subphotic <span class="hlt">zone</span>). A decrease of tropical components from west to east across the platform implies that warm oceanic currents (possibly related to a proto-Leeuwin Current), as well as a period of warm climate (Miocene Climatic Optimum), resulted in subtropical deposition at <span class="hlt">southern</span> latitudes. The <span class="hlt">Southern</span> Ocean extended inboard ~ 450 km from the shelf edge during Nullarbor Limestone deposition, but interpreted paleodepths did not extend much below the base of the photic <span class="hlt">zone</span>. A small slope angle (~ 0.02°) over a wide shelf (~ 300,000 km2) implies deposition on an epeiric platform or epeiric ramp. A Miocene barrier reef was likely coeval with Nullarbor Limestone deposition. Therefore, the inboard portion of the Nullarbor Limestone can be considered part of an extensive back-reef lagoon system on a rimmed epeiric platform, perhaps attaining a size similar to the modern Great Barrier Reef system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27..628S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27..628S"><span>Energy and Mass Balance At Gran Campo Nevado, Patagonia, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schneider, C.; Kilian, R.; Casassa, G.</p> <p></p> <p>The Gran Campo Nevado (GCN) Ice Cap on Peninsula Muñoz Gamero, <span class="hlt">Chile</span>, is lo- cated in the southernmost part of the Patagonian Andes at 53S. It comprises an ice cap and numerous outlet glaciers which mostly end in proglacial lakes at sea level. The total ice covered area sums up to approximately 250 km2. GCN forms the only major ice body between the <span class="hlt">Southern</span> Patagonian Icefield and the Street of Magallan. Its almost unique location in the <span class="hlt">zone</span> of the all-year westerlies makes it a region of key interest in terms of glacier and climate change studies of the westwind <span class="hlt">zone</span> of the <span class="hlt">Southern</span> Hemisphere. Mean annual temperature of approximately +5C at sea level and high precipitation of about 8.000 mm per year lead to an extreme turn-over of ice mass from the accumulation area of the GCN Ice Cap to the ablation areas of the outlet glaciers. Since October 1999 an automated weather station (AWS) is run continuously in the area at Bahia Bahamondes for monitoring climate parameters. From February to April 2000 an additional AWS was operated on Glaciar Lengua a small outlet glacier of GCN to the north-west. Ablation has been measured at stakes during the same pe- riod. The aim of this study, was to obtain point energy and mass balance on Glaciar Lengua. The work was conducted as part of the international and interdisciplinary working group SGran Campo NevadoT and supported by the German Research Foun- & cedil;dation (DFG). Energy balance was calculated using the bulk approach formulas and calibrated to the measured ablation. It turns out, that sensible heat transfer is the major contribution to the energy balance. Since high cloud cover rates prevail, air tempera- ture is the key factor for the energy balance of the glacier. Despite high rain fall rates, energy input from rain fall is of only minor importance to the overall energy balance. From the energy balance computed, it was possible to derive summer-time degree-day factors for Glaciar Lengua. With data from the nearby</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70016563','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70016563"><span>Late Holocene tectonics and paleoseismicity, <span class="hlt">southern</span> Cascadia subduction <span class="hlt">zone</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Clarke, S.H.; Carver, G.A.</p> <p>1992-01-01</p> <p>Holocene deformation indicative of large subduction-<span class="hlt">zone</span> earthquakes has occurred on two large thrust fault systems in the Humboldt Bay region of northern California. Displaced stratigraphic markers record three offsets of 5 to 7 meters each on the Little Salmon fault during the past 1700 years. Smaller and less frequent Holocene displacements have occurred in the Mad River fault <span class="hlt">zone</span>. Elsewhere, as many as five episodes of sudden subsidence of marsh peats and fossil forests and uplift of marine terraces are recorded. Carbon-14 dates suggest that the faulting, subsidence, and uplift events were synchronous. Relations between magnitude and various fault-offset parameters indicate that earthquakes accompanying displacements on the Little Salmon fault had magnitudes of at least 7.6 to 7.8. More likely this faulting accompanied rupture of the boundary between the Gorda and North American plates, and magnitudes were about 8.4 or greater.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17756070','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17756070"><span>Late holocene tectonics and paleoseismicity, <span class="hlt">southern</span> cascadia subduction <span class="hlt">zone</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Clarke, S H; Carver, G A</p> <p>1992-01-10</p> <p>Holocene deformation indicative of large subduction-<span class="hlt">zone</span> earthquakes has occurred on two large thrust fault systems in the Humboldt Bay region of northern California. Displaced stratigraphic markers record three offsets of 5 to 7 meters each on the Little Salmon fault during the past 1700 years. Smaller and less frequent Holocene displacements have occurred in the Mad River fault <span class="hlt">zone</span>. Elsewhere, as many as five episodes of sudden subsidence of marsh peats and fossil forests and uplift of marine terraces are recorded. Carbon-14 dates suggest that the faulting, subsidence, and uplift events were synchronous. Relations between magnitude and various fault-offset parameters indicate that earthquakes accompanying displacements on the Little Salmon fault had magnitudes of at least 7.6 to 7.8. More likely this faulting accompanied rupture of the boundary between the Gorda and North American plates, and magnitudes were about 8.4 or greater.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.T13G2716M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.T13G2716M"><span>Late magmatic stage of the <span class="hlt">zoned</span> Caleu pluton (Central <span class="hlt">Chile</span>): insights from zircon crystallization conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Molina, P. G.; Parada, M.; Gutierrez, F. J.; Chang-Qiang, M.; Jianwei, L.; Yuanyuan, L.</p> <p>2012-12-01</p> <p>The Caleu pluton consists of three N-S elongated lithological <span class="hlt">zones</span>: Gabbro-Diorite <span class="hlt">Zone</span> (GDZ), Tonalite <span class="hlt">Zone</span> (TZ) and Granodiorite <span class="hlt">Zone</span> (GZ); western, middle and eastern portions of the pluton, respectively. The <span class="hlt">zones</span> are thought to be previously differentiated in a common, isotopically depleted (Sr-Nd), subjacent magma reservoir at a 4 kbar equivalent depth. The emplacement should have occurred at the climax of the Cretaceous rifting. We present preliminary results of U238/Pb206 zircon geochronology; zircon saturation, Tsat(Zrn), and crystallization temperatures (Ti-in-Zrn); as well as relative oxidation states at time of crystallization, based on: (i) the sluggish REE and HFSE subsolidus diffusivities in zircon; (ii) the behavior of Ti4+↔Si4+ and Ce4+↔Zr4+ isovalent replacement, in addition to a constrained TiO2 activity in almost all typical crustal rocks; and (iii) relative oxidation states at time of crystallization, respectively. The latter are obtained by interpolation of the partition coefficients of trivalent (REE) and tetravalent (HFSE) curves in Onuma diagrams for each zircon, and then estimating relative Ce(IV)/Ce(III) ratios. Results obtained from 4 samples (a total of 77 zircon grains) collected from the three mentioned lithological <span class="hlt">zones</span> indicate U/Pb ages of approximately 99.5 ±1.5 Ma, 96.8 ±0.6 Ma, and 94.4 +2.2 -0.8 Ma; and Ti-in Zrn ranges of ca. 720-870°C, ca. 680-820°C and ca. 750-840°C, for the GDZ, TZ and GZ samples, respectively. On the other hand Tsat(Zrn) of ca. 750-780°C in the TZ, and ca. 830-890°C in the GZ, were obtained. As expected saturation temperatures are similar or higher than Ti-in-Zrn obtained in zircon grains of TZ and GZ, respectively. Cathodoluminiscence images in zircon suggest a magmatic origin, due to absence of complex <span class="hlt">zoning</span> patterns and fairly well conserved morphologies. Exceptionally the GDZ sample zircons show evidence of inheritance, indicating a xenocrystic and/or antecrystic origin. A relative Ce</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19030659','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19030659"><span>[Consumption of antidepressants in <span class="hlt">Chile</span> from 1992 to 2004].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jirón, Marcela; Machado, Márcio; Ruiz, Inés</p> <p>2008-09-01</p> <p>Data from the Ministry of Health show that in <span class="hlt">Chile</span> in 2004, 17% of the population had some form of depression, and mood disorders are the tenth cause of disability-adjusted life years (DALY) loss. To determine consumption of antidepressants (ADs) in <span class="hlt">Chile</span> from 1992 to 2004. National sales data were obtained from the company IMS Health <span class="hlt">Chile</span> and converted into defined daily doses (DDDs) per 1,000 inhabitants per day. Available ADs were classified in four pharmacological groups (i.e., serotonin-norepinephrine reuptake inhibitors, SNRLs; selective-serotonin reuptake inhibitors, SSRLs; tricyclic antidepressants, TCAs; and others). Total economic burden of ADs utilization and cost per DDDs were also calculated. Trends over time were analyzed using Pearson-R2. Total ADs consumption in <span class="hlt">Chile</span> measured by DDDs per 1,000 inhabitants per day (DHD) increased linearly (y =0.901x + 1.9129; R2 =0.9296; p <0.001) from 2.5 in 1992 to 11.7 in 2004 (total growth of 470.2%). SSRLs were the drug class with higher consumption, and fluoxetine the most commonly consumed antidepressant. SSRLs were the drugs that dominated the market representing 79% of the total drug consumption throughout the years. Total economic burden of ADs in <span class="hlt">Chile</span> (total cost of DDDs consumed) increased from US$65.4 million in 2001 to US$74.6 million in 2004 (14% increase). Average cost per DDD of all AD increased linearly, however not significantly from US$ 0.94 in 2001 to US$ 1.04 in 2004 (y =0.0362x + 0.8784; R2 =0.7382; p =0,262). DDDs per 1,000 inhabitants per day increased linearly over 470% from 1992-2004. SSRLs were the most commonly consumed drugs in <span class="hlt">Chile</span>. Future research should evaluate the cost-effectiveness of antidepressants in <span class="hlt">Chile</span>, comparing the results with drug utilization, and determining if unnecessary expenditures have been paid out.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14577930','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14577930"><span>Behavioral problems and tobacco use among adolescents in <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Caris, Luis; Varas, Marianela; Anthony, Christopher B; Anthony, James C</p> <p>2003-08-01</p> <p>To examine the association between behavioral problems and tobacco smoking among adolescent students in <span class="hlt">Chile</span>. Data were drawn from a study that included questionnaire surveys of 46 907 school-attending adolescents in all 13 of the administrative regions of <span class="hlt">Chile</span>. Assessments were based on an adapted, Spanish-language version of the Drug Use Screening Inventory. The conditional form of the logistic regression model was used for analysis, with matching of students on individual schools, and with further statistical adjustments for sex, age, and selected risk factors. The prevalence of tobacco smoking among the adolescents was very high across all of <span class="hlt">Chile</span>, with a level between 56% and 65% in each of the 13 regions. The estimated odds of tobacco use in youths at the highest level of behavioral problems was about twice that for youths at the lowest levels, both before and after controlling for sex, age, lack of participation in recreational activities, level of irritability, and levels of problems with school, family attention, and mental health. These findings help to complement and complete the evidence of prior studies on tobacco smoking among adolescents with behavior problems, including recent research on Central American youths. Although the magnitude of observed associations in <span class="hlt">Chile</span> was not as great as that for the associations found in Central America, both the strength of these associations and their statistical significance were observed throughout <span class="hlt">Chile</span>. This is the first study in <span class="hlt">Chile</span> on potentially causal relationships such as these.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.2320I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.2320I"><span>Glacialmorphological reconstruction of glacier advances and glacial lake outburst floods at the Cachapoal glacier in the Dry Central Andes of <span class="hlt">Chile</span> (34°S)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Iturrizaga, Lasafam; Charrier, Reynaldo</p> <p>2013-04-01</p> <p>Throughout the Andes Mountain range of South America a general trend of glacier shrinkage has taken place in the last century. Only a few glaciers have shown a rather non-continuous trend of glacier retreat and temporally advanced or even surged during the mid-19th to 20th century. One of the earliest assumed glacier surges has occurred in the upper Cachapoal catchment area at the homonymous glacier. In climatic respect the Cachapoal glacier is located in the transition <span class="hlt">zone</span> from the most <span class="hlt">southern</span> part of the Dry Central Andes of <span class="hlt">Chile</span> to the more humid <span class="hlt">zone</span> of the Wet Andes. The region is affected mainly by winter precipitation deriving from the Westerlies. The debris-covered, 12 km-long Cachapoal glacier represents one of the largest valley glaciers in the Central Andes. It is an avalanche-fed glacier with an almost 1500 m-high head wall in its upper catchment area flowing down from Picos del Barroso (5180 m) and terminates at an elevation of 2630 m a.s.l. with a bifurcated glacier tongue. A large moraine complex, almost 2 km in length and 500 m in width, separates the two glacier lobes. During times of advanced glacier tongue positions the Ríos Molina and Cachapoal may be have blocked independently at two distinct localities which are situated about 2300 m apart from each other. A blockage with temporal lake formation has occurred at least in the years 1848, 1955 and 1981 (cf. Plagemann 1887, Peña 1981), from which the rupture of the earliest glacier barrier has been the most devastating. This event is locally reminded as "la gran avenida en seco" in the historical record. Geomorphological evidence of the past historical and modern glacier expansions is given in the proglacial area by a fresh dead-ice hummocky topography and glacial trimlines at the valley flanks. More down valley broad outwash plains and boulder clusters indicate past high energy floods produced by glacier lake outbursts. Regarding the small size of the catchment area of the Río Molina</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoJI.201.1868B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoJI.201.1868B"><span>Sensitivity analysis of earthquake-induced static stress changes on volcanoes: the 2010 Mw 8.8 <span class="hlt">Chile</span> earthquake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bonali, F. L.; Tibaldi, A.; Corazzato, C.</p> <p>2015-06-01</p> <p>In this work, we analyse in detail how a large earthquake could cause stress changes on volcano plumbing systems and produce possible positive feedbacks in promoting new eruptions. We develop a sensitivity analysis that considers several possible parameters, providing also new constraints on the methodological approach. The work is focus on the Mw 8.8 2010 earthquake that occurred along the <span class="hlt">Chile</span> subduction <span class="hlt">zone</span> near 24 historic/Holocene volcanoes, located in the <span class="hlt">Southern</span> Volcanic <span class="hlt">Zone</span>. We use six different finite fault-slip models to calculate the static stress change, induced by the coseismic slip, in a direction normal to several theoretical feeder dykes with various orientations. Results indicate different magnitudes of stress change due to the heterogeneity of magma pathway geometry and orientation. In particular, the N-S and NE-SW-striking magma pathways suffer a decrease in stress normal to the feeder dyke (unclamping, up to 0.85 MPa) in comparison to those striking NW-SE and E-W, and in some cases there is even a clamping effect depending on the magma path strike. The diverse fault-slip models have also an effect (up to 0.4 MPa) on the results. As a consequence, we reconstruct the geometry and orientation of the most reliable magma pathways below the 24 volcanoes by studying structural and morphometric data, and we resolve the stress changes on each of them. Results indicate that: (i) volcanoes where post-earthquake eruptions took place experienced earthquake-induced unclamping or very small clamping effects, (ii) several volcanoes that did not erupt yet are more prone to experience future unrest, from the point of view of the host rock stress state, because of earthquake-induced unclamping. Our findings also suggest that pathway orientation plays a more relevant role in inducing stress changes, whereas the depth of calculation (e.g. 2, 5 or 10 km) used in the analysis, is not key a parameter. Earthquake-induced magma-pathway unclamping might contribute to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=238500','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=238500"><span>Spatial Distribution, Structure, Biomass, and Physiology of Microbial Assemblages across the <span class="hlt">Southern</span> Ocean Frontal <span class="hlt">Zones</span> during the Late Austral Winter</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hanson, Roger B.; Lowery, H. Kenneth</p> <p>1985-01-01</p> <p>We examined the spatial distributions of picoplankton, nanoplankton, and microplankton biomass and physiological state relative to the hydrography of the <span class="hlt">Southern</span> Ocean along 90° W longitude and across the Drake Passage in the late austral winter. The eastern South Pacific Ocean showed some large-scale biogeographical differences and size class variability. Microbial ATP biomass was greatest in euphotic surface waters. The horizontal distributions of microbial biomass and physiological state (adenylate energy charge ratio) coincided with internal currents (fronts) of the Antarctic Circumpolar Current. In the Drake Passage, the biological scales in the euphotic and aphotic <span class="hlt">zones</span> were complex, and ATP, total adenylate, and adenylate energy charge ratio isopleths were compressed due to the extension of the sea ice from Antarctica and constriction of the Circumpolar Current through the narrow passage. The physiological state of microbial assemblages and biomass were much higher in the Drake Passage than in the eastern South Pacific Ocean. The temperature of Antarctic waters, not dissolved organic carbon, was the major variable controlling picoplankton growth. Estimates of picoplankton production based on ATP increments with time suggest that production under reduced predation pressure was 1 to 10 μg of carbon per liter per day. Our results demonstrate the influence of large-scale hydrographic processes on the distribution and structure of microplankton, nanoplankton, and picoplankton across the <span class="hlt">Southern</span> Ocean. PMID:16346777</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2982231','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2982231"><span>Iron defecation by sperm whales stimulates carbon export in the <span class="hlt">Southern</span> Ocean</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lavery, Trish J.; Roudnew, Ben; Gill, Peter; Seymour, Justin; Seuront, Laurent; Johnson, Genevieve; Mitchell, James G.; Smetacek, Victor</p> <p>2010-01-01</p> <p>The iron-limited <span class="hlt">Southern</span> Ocean plays an important role in regulating atmospheric CO2 levels. Marine mammal respiration has been proposed to decrease the efficiency of the <span class="hlt">Southern</span> Ocean biological pump by returning photosynthetically fixed carbon to the atmosphere. Here, we show that by consuming prey at depth and defecating iron-rich liquid faeces into the photic <span class="hlt">zone</span>, sperm whales (Physeter macrocephalus) instead stimulate new primary production and carbon export to the deep ocean. We estimate that <span class="hlt">Southern</span> Ocean sperm whales defecate 50 tonnes of iron into the photic <span class="hlt">zone</span> each year. Molar ratios of Cexport ∶Feadded determined during natural ocean fertilization events are used to estimate the amount of carbon exported to the deep ocean in response to the iron defecated by sperm whales. We find that <span class="hlt">Southern</span> Ocean sperm whales stimulate the export of 4 × 105 tonnes of carbon per year to the deep ocean and respire only 2 × 105 tonnes of carbon per year. By enhancing new primary production, the populations of 12 000 sperm whales in the <span class="hlt">Southern</span> Ocean act as a carbon sink, removing 2 × 105 tonnes more carbon from the atmosphere than they add during respiration. The ability of the <span class="hlt">Southern</span> Ocean to act as a carbon sink may have been diminished by large-scale removal of sperm whales during industrial whaling. PMID:20554546</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H41G1433M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H41G1433M"><span>Improving the flow representation in a stochastic programming model for hydropower operations in <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morales, Y.; Olivares, M. A.; Vargas, X.</p> <p>2015-12-01</p> <p>This research aims to improve the representation of stochastic water inflows to hydropower plants used in a grid-wide, power production scheduling model in central <span class="hlt">Chile</span>. The model prescribes the operation of every plant in the system, including hydropower plants located in several basins, and uses stochastic dual dynamic programming (SDDP) with possible inflow scenarios defined from historical records. Each year of record is treated as a sample of weekly inflows to power plants, assuming this intrinsically incorporates spatial and temporal correlations, without any further autocorrelation analysis of the hydrological time series. However, standard good practice suggests the use of synthetic flows instead of raw historical records.The proposed approach generates synthetic inflow scenarios based on hydrological modeling of a few basins in the system and transposition of flows with other basins within so-called homogeneous <span class="hlt">zones</span>. Hydrologic models use precipitation and temperature as inputs, and therefore this approach requires producing samples of those variables. Development and calibration of these models imply a greater demand of time compared to the purely statistical approach to synthetic flows. This approach requires consideration of the main uses in the basins: agriculture and hydroelectricity. Moreover a geostatistical analysis of the area is analyzed to generate a map that identifies the relationship between the points where the hydrological information is generated and other points of interest within the power system. Consideration of homogeneous <span class="hlt">zones</span> involves a decrease in the effort required for generation of information compared with hydrological modeling of every point of interest. It is important to emphasize that future scenarios are derived through a probabilistic approach that incorporates the features of the hydrological year type (dry, normal or wet), covering the different possibilities in terms of availability of water resources. We present</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22493103','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22493103"><span>Ecology of rodent-associated hantaviruses in the <span class="hlt">Southern</span> Cone of South America: Argentina, <span class="hlt">Chile</span>, Paraguay, and Uruguay.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Palma, R Eduardo; Polop, Jaime J; Owen, Robert D; Mills, James N</p> <p>2012-04-01</p> <p>Thirteen hantavirus genotypes, associated with at least 12 sigmodontine reservoir rodents, have been recognized in the four countries that represent the <span class="hlt">Southern</span> Cone of South America. Host-virus relationships are not as well defined as in North America; several <span class="hlt">Southern</span> Cone hantaviruses appear to share a common host and some viruses do not occur throughout the range of their host. Although hantavirus-host relationships in the <span class="hlt">Southern</span> Cone are less strictly concordant with the single-host-single-virus pattern reported elsewhere, recent studies suggest that much of the ambiguity may result from an incomplete understanding of host and hantavirus systematics. Although some <span class="hlt">Southern</span> Cone host species are habitat generalists, some sympatric species are habitat specialists, helping to explain how some strict host-virus pairings may be maintained. In some cases, host population densities were higher in peridomestic habitats and prevalence of hantavirus infection was higher in host populations in peridomestic habitats. Seasonal and multiyear patterns in climate and human disturbance affect host population densities, prevalence of infection, and disease risk to humans. Unusually high hantavirus antibody prevalence in indigenous human populations may be associated with frequent and close contact with host rodents. Ongoing studies are improving our understanding of hantavirus-host ecology and providing tools that may predict human risk.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004DSRI...51..307P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004DSRI...51..307P"><span>Geochemical particle fluxes in the <span class="hlt">Southern</span> Indian Ocean seasonal ice <span class="hlt">zone</span>: Prydz Bay region, East Antarctica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pilskaln, C. H.; Manganini, S. J.; Trull, T. W.; Armand, L.; Howard, W.; Asper, V. L.; Massom, R.</p> <p>2004-02-01</p> <p>Time-series sediment traps were deployed between December 1998 and January 2000 and from March 2000 to February 2001 at two offshore Prydz Bay sites within the seasonal ice <span class="hlt">zone</span> (SIZ) of the <span class="hlt">Southern</span> Indian Ocean located between 62-63°S and 73-76°E to quantify seasonal biogeochemical particle fluxes. Samples were obtained from traps placed at 1400, 2400, and 3400 m during the first deployment year (PZB-1) and from 3300 m in the second deployment year (PZB-2). All geochemical export fluxes were highly seasonal with primary peaks occurring during the austral summer and relatively low fluxes prevailing through the winter months. Secondary flux peaks in mid-winter and in early spring were suggestive of small-scale, sea-ice break-up events and the spring retreat of seasonal ice, respectively. Biogenic silica represented over 70% (by weight) of the collected trap material and provided an annual opal export of 18 g m -2 to 1 km and 3-10 g m -2 to 3 km. POC fluxes supplied an annual export of approximately 1 g m -2, equal to the estimated ocean-wide average. Elevated particulate C org/C inorg and Si bio/C inorg molar ratios indicate a productive, diatom-dominated system, although consistently small fluxes of planktonic foraminifera and pteropod shells document a heterotrophic source of carbonate to deeper waters in the SIZ. The observation of high Si bio/C org ratios and the δ15N time-series data suggest enhanced rates of diatom-POC remineralization in the upper 1000 m relative to bioSiO 2. The occurrence in this region of a pronounced temperature minimum, associated with a strong pycnocline and subsurface particle maximum at 50-100 m, may represent a <span class="hlt">zone</span> where sinking, diatom-rich particulates temporarily accumulate and POC is remineralized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24014488','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24014488"><span>Cultural meanings of musculoskeletal diseases in <span class="hlt">Chile</span>'s Mapuche Population.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Alarcon, Ana M; Vidal, Aldo; Castro, Marcela</p> <p>2013-10-01</p> <p>Eight out of 10 Mapuche indigenous women have a musculoskeletal disorder (MSD) and do not seek early medical aid. To study both the cultural meanings and implications of MSD from the Mapuche worldview. Ethnographic study carried out from 2008 to 2011 on indigenous reserves in <span class="hlt">southern</span> <span class="hlt">Chile</span>. Sixty-four Mapuches participated in comprehensive interviews, which were transcribed and analyzed by the research team. Five cultural domains: (a) foro kutran/bone disease is the general denomination of MSD; (b) Re-Rume Kutran/progressive and incurable course, refers to the course of the disease; (c) Kalül fücha mawiza/body is an old tree, describes internal manifestations such as worn bones, dry body, weak blood, and spiritual weakness; (d) witrür tripai foro/deformation is the external manifestation of MSD; and (e) Reñma ka lof kutran/family and community suffering refers to the impact of MSD. The explanation of MSD is consistent with the integrated body-nature-spirit worldview of the Mapuche. To provide cultural nursing health care so that patients receive prompt diagnosis and care.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22854694','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22854694"><span>[Main characteristics of current biomedical research, in <span class="hlt">Chile</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Valdés S, Gloria; Armas M, Rodolfo; Reyes B, Humberto</p> <p>2012-04-01</p> <p>Biomedical research is a fundamental tool for the development of a country, requiring human and financial resources. To define some current characteristics of biomedical research, in <span class="hlt">Chile</span>. Data on entities funding bio-medical research, participant institutions, and the number of active investigators for the period 2007-2009 were obtained from institutional sources; publications indexed in PubMed for 2008-2009 were analysed. Most financial resources invested in biomedical research projects (approximately US$ 19 million per year) came from the "Comisión Nacional de Investigación Científica y Tecnológica" (CONICYT), a state institution with 3 independent Funds administering competitive grant applications open annually to institutional or independent investigators in <span class="hlt">Chile</span>. Other sources and universities raised the total amount to US$ 26 million. Since 2007 to 2009, 408 investigators participated in projects funded by CONICYT. The main participant institutions were Universidad de <span class="hlt">Chile</span> and Pontificia Universidad Católica de <span class="hlt">Chile</span>, both adding up to 84% of all funded projects. Independently, in 2009,160 research projects -mainly multi centric clinical trials- received approximately US$ 24 million from foreign pharmaceutical companies. Publications listed in PubMed were classified as "clinical research" (n = 879, including public health) or "basic biomedical research" (n = 312). Biomedical research in <span class="hlt">Chile</span> is mainly supported by state funds and university resources, but clinical trials also obtained an almost equivalent amount from foreign resources. Investigators are predominantly located in two universities. A small number of MD-PhD programs are aimed to train and incorporate new scientists. Only a few new Medical Schools participate in biomedical research. A National Registry of biomedical research projects, including the clinical trials, is required among other initiatives to stimulate research in biomedical sciences in <span class="hlt">Chile</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JVGR..341..104R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JVGR..341..104R"><span>Structural controls on fluid circulation at the Caviahue-Copahue Volcanic Complex (CCVC) geothermal area (<span class="hlt">Chile</span>-Argentina), revealed by soil CO2 and temperature, self-potential, and helium isotopes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Roulleau, Emilie; Bravo, Francisco; Pinti, Daniele L.; Barde-Cabusson, Stéphanie; Pizarro, Marcela; Tardani, Daniele; Muñoz, Carlos; Sanchez, Juan; Sano, Yuji; Takahata, Naoto; de la Cal, Federico; Esteban, Carlos; Morata, Diego</p> <p>2017-07-01</p> <p>Natural geothermal systems are limited areas characterized by anomalously high heat flow caused by recent tectonic or magmatic activity. The heat source at depth is the result of the emplacement of magma bodies, controlled by the regional volcano-tectonic setting. In contrast, at a local scale a well-developed fault-fracture network favors the development of hydrothermal cells, and promotes the vertical advection of fluids and heat. The <span class="hlt">Southern</span> Volcanic <span class="hlt">Zone</span> (SVZ), straddling <span class="hlt">Chile</span> and Argentina, has an important, yet unexplored and undeveloped geothermal potential. Studies on the lithological and tectonic controls of the hydrothermal circulation are therefore important for a correct assessment of the geothermal potential of the region. Here, new and dense self-potential (SP), soil CO2 and temperature (T) measurements, and helium isotope data measured in fumaroles and thermal springs from the geothermal area located in the north-eastern flank of the Copahue volcanic edifice, within the Caviahue Caldera (the Caviahue-Copahue Volcanic Complex - CCVC) are presented. Our results allowed to the constraint of the structural origin of the active thermal areas and the understanding of the evolution of the geothermal system. NE-striking faults in the area, characterized by a combination of SP, CO2, and T maxima and high 3He/4He ratios (up to 8.16 ± 0.21Ra, whereas atmospheric Ra is 1.382 × 10- 6), promote the formation of vertical permeability preferential pathways for fluid circulation. WNW-striking faults represent low-permeability pathways for hydrothermal fluid ascent, but promote infiltration of meteoric water at shallow depths, which dilute the hydrothermal input. The region is scattered with SP, CO2, and T minima, representing self-sealed <span class="hlt">zones</span> characterized by impermeable altered rocks at depth, which create local barriers for fluid ascent. The NE-striking faults seem to be associated with the upflowing <span class="hlt">zones</span> of the geothermal system, where the boiling process</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA12864.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA12864.html"><span>Coastal <span class="hlt">Chile</span> Perspective View</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2010-03-04</p> <p>This perspective view from NASA Shuttle Radar Topography Mission of coastal <span class="hlt">Chile</span> indicates the epicenter red marker of the 8.8 earthquake on Feb. 27, 2010, just offshore of the Maule region in the Bahia de Chanco.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED352108.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED352108.pdf"><span>La atencion preescolar en <span class="hlt">Chile</span>: desafios para la redemocratizacion (Preschool Care in <span class="hlt">Chile</span>: Challenges for Redemocratization. Discussion Paper No. 13).</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Filp, Johanna; Undurrage, Consuelo</p> <p></p> <p>This paper examines the current status of programs for preschool children in <span class="hlt">Chile</span>. Section 1 of the paper provides an overview of the situation of preschool children in <span class="hlt">Chile</span>. The country's population includes more than 1.6 million children between the ages of 0 and 5 years 11 months, and in urban areas, 18.4 percent of children between the ages…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA469009','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA469009"><span>Virtual Borders Between <span class="hlt">Chile</span> and Its Neighbors: Argentina, Peru and Bolivia</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2007-03-30</p> <p>Estadísticas, “ Inmigrantes en <span class="hlt">Chile</span> ”, Santiago Census, 2002 20 ...Studies and Research Center, 1998), 13 22 Military Studies and Research Center, <span class="hlt">Chile</span> en la Region. CESIM. 2001; available from <http...Estatuto de Inversiones Extranjeras en <span class="hlt">Chile</span> ”, ( Santiago: 1974), Capitulo I,19 35 The International Center for Adjustment of Disputes of Investment</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/468441','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/468441"><span>Nutrition and national development: the case of <span class="hlt">Chile</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Solimano, G; Hakim, P</p> <p>1979-01-01</p> <p>This study is an historical analysis of food consumption and nutrition in <span class="hlt">Chile</span> emphasizing the influence of political and economic factors on nutritional standards. It attempts to document and explain the persistence of malnutrition as a widespread social problem in <span class="hlt">Chile</span> even as the country achieved a relatively advanced state of economic development and boasted an unusually progressive record of social legislation. The major findings of the study were: (a) <span class="hlt">Chile</span>'s pattern of development, social reform efforts notwithstanding, consistently discriminated against low-income groups, and (b) this discrimination perpetuated low standards of nutrition and low levels of food consumption among the country's poor and undermined the effectiveness of specific measures to alleviate malnutrition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JAESc..78...39C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JAESc..78...39C"><span>Proterozoic orogens in <span class="hlt">southern</span> Peninsular India: Contiguities and complexities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chetty, T. R. K.; Santosh, M.</p> <p>2013-12-01</p> <p>The Precambrian terranes of <span class="hlt">southern</span> Peninsular India have been central to discussions on the history of formation and breakup of supercontinents. Of particular interest are the Proterozoic high grade metamorphic orogens at the <span class="hlt">southern</span> and eastern margins of the Indian shield, skirting the 3.4 Ga Dharwar craton which not only preserve important records of lower crustal processes and lithospheric geodynamics, but also carry imprints of the tectonic framework related to the assembly of the major Neoproterozoic supercontinents - Rodinia and Gondwana. These Proterozoic orogens are described as <span class="hlt">Southern</span> Granulite Terrane (SGT) in the <span class="hlt">southern</span> tip and the Eastern Ghats Mobile Belt (EGMB) in the eastern domains of the peninsula. The contiguity of these orogens is broken for a distance of ˜400 km and disappears in the Bay of Bengal. These orogens expose windows of middle to lower crust with well-preserved rock records displaying multiple tectonothermal events and multiphase exhumation paths.Recent studies in these orogens have led to the recognition of discrete crustal blocks or terranes separated by major shear <span class="hlt">zone</span> systems, some of which represent collisional sutures. The SGT and EGMB carry several important features such as fold-thrust tectonics, regional granulite facies metamorphism of up to ultrahigh-temperature conditions in some cases, multiple P-T paths, development of lithospheric shear <span class="hlt">zones</span>, emplacement of ophiolites, presence of alkaline and anorthositic complexes, development of crustal-scale "flower structures", transpressional strains, and reactivation tectonics. A heterogeneous distribution of different metamorphic and magmatic assemblages with distinct spatial and temporal strain variations in shaping the fabric elements in different blocks is identified. Both EGMB and SGT share a common transpressional deformation history during the latest Neoproterozoic characterized by the steepening of the initial low angle crustal scale structures leading to a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ECSS..150...67H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ECSS..150...67H"><span>Local extirpations and regional declines of endemic upper beach invertebrates in <span class="hlt">southern</span> California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hubbard, D. M.; Dugan, J. E.; Schooler, N. K.; Viola, S. M.</p> <p>2014-10-01</p> <p>Along the world's highly valued and populous coastlines, the upper intertidal <span class="hlt">zones</span> of sandy beach ecosystems and the biodiversity that these <span class="hlt">zones</span> support are increasingly threatened by impacts of human activities, coastal development, erosion, and climate change. The upper <span class="hlt">zones</span> of beaches typically support invertebrates with restricted distributions and dispersal, making them particularly vulnerable to habitat loss and fragmentation. We hypothesized that disproportionate loss or degradation of these <span class="hlt">zones</span> in the last century has resulted in declines of upper shore macroinvertebrates in <span class="hlt">southern</span> California. We identified a suite of potentially vulnerable endemic upper beach invertebrates with direct development, low dispersal and late reproduction. Based on the availability of printed sources and museum specimens, we investigated historical changes in distribution and abundance of two intertidal isopod species (Tylos punctatus, Alloniscus perconvexus) in <span class="hlt">southern</span> California. Populations of these isopods have been extirpated at numerous historically occupied sites: T. punctatus from 16 sites (57% decrease), and A. perconvexus from 14 sites (64% decrease). During the same period, we found evidence of only five colonization events. In addition, the northern range limit of the <span class="hlt">southern</span> species, T. punctatus, moved south by 31 km (8% of range on California mainland) since 1971. Abundances of T. punctatus have declined on the mainland coast; only three recently sampled populations had abundances >7000 individuals m-1. For A. perconvexus populations, abundances >100 individuals m-1 now appear to be limited to the northern part of the study area. Our results show that numerous local extirpations of isopod populations have resulted in regional declines and in greatly reduced population connectivity in several major littoral cells of <span class="hlt">southern</span> California. Two of the six major littoral cells (Santa Barbara and Zuma) in the area currently support 74% of the remaining isopod</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.nrel.gov/csp/solarpaces/by_country_detail.cfm/country=CL','SCIGOVWS'); return false;" href="https://www.nrel.gov/csp/solarpaces/by_country_detail.cfm/country=CL"><span>Concentrating Solar Power Projects in <span class="hlt">Chile</span> | Concentrating Solar Power |</span></a></p> <p><a target="_blank" href="http://www.science.gov/aboutsearch.html">Science.gov Websites</a></p> <p></p> <p></p> <p>;alphabetical by project name. You can browse a project <em>profile</em> by clicking on <em>the</em> project name. Atacama-1 NREL</A> <span class="hlt">Chile</span> Concentrating solar power (CSP) projects <em>in</em> <span class="hlt">Chile</span> are listed belowâ€"</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.3772M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.3772M"><span>Streamflow responses in <span class="hlt">Chile</span> to megathrust earthquakes in the 20th and 21st centuries</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mohr, Christian; Manga, Michael; Wang, Chi-yuen; Korup, Oliver</p> <p>2016-04-01</p> <p>Both coseismic static stress and dynamic stresses associated with seismic waves may cause responses in hydrological systems. Such responses include changes in the water level, hydrochemistry and streamflow discharge. Earthquake effects on hydrological systems provide a means to study the interaction between stress changes and regional hydrology, which is otherwise rarely possible. <span class="hlt">Chile</span> is a country of frequent and large earthquakes and thus provides abundant opportunities to study such interactions and processes. We analyze streamflow responses in <span class="hlt">Chile</span> to several megathrust earthquakes, including the 1943 Mw 8.1 Coquimbo, 1950 Mw 8.2 Antofagasta, 1960 Mw 9.5 Valdivia, 1985 Mw 8.0 Valparaiso, 1995 Mw 8.0 Antofagasta, 2010 Mw 8.8 Maule, and the 2014 Mw 8.2 Iquique earthquakes. We use data from 716 stream gauges distributed from the Altiplano in the North to Tierra del Fuego in the South. This network covers the Andes mountain ranges, the central valley, the Coastal Mountain ranges and (mainly in the more <span class="hlt">southern</span> parts) the Coastal flats. We combine empirical magnitude-distance relationships, machine learning tools, and process-based modeling to characterize responses. We first assess the streamflow anomalies and relate these to topographical, hydro-climatic, geological and earthquake-related (volumetric and dynamic strain) factors using various classifiers. We then apply 1D-groundwater flow modeling to selected catchments in order to test competing hypotheses for the origin of streamflow changes. We show that the co-seismic responses of streamflow mostly involved increasing discharges. We conclude that enhanced vertical permeability can explain most streamflow responses at the regional scale. The total excess water released by a single earthquake, i.e. the Maule earthquake, yielded up to 1 km3. Against the background of megathrust earthquakes frequently hitting <span class="hlt">Chile</span>, the amount of water released by earthquakes is substantial, particularly for the arid northern</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JSAES..71..309A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JSAES..71..309A"><span>Present-day stress tensors along the <span class="hlt">southern</span> Caribbean plate boundary <span class="hlt">zone</span> from inversion of focal mechanism solutions: A successful trial</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Audemard M., Franck A.; Castilla, Raymi</p> <p>2016-11-01</p> <p>This paper presents a compilation of 16 present-day stress tensors along the <span class="hlt">southern</span> Caribbean plate boundary <span class="hlt">zone</span> (PBZ), and particularly in western and along northern Venezuela. As a trial, these new stress tensors along PBZ have been calculated from inversion of 125 focal mechanism solutions (FMS) by applying the Angelier & Mechler's dihedral method, which were originally gathered by the first author and published in 2005. These new tensors are compared to those 59 tensors inverted from fault-slip data measured only in Plio-Quaternary sedimentary rocks, compiled in Audemard et al. (2005), which were originally calculated by several researchers through the inversion methods developed by Angelier and Mechler or Etchecopar et al. The two sets of stress tensors, one derived from geological data and the other one from seismological data, compare very well throughout the PBZ in terms of both stress orientation and shape of the stress tensor. This region is characterized by a compressive strike-slip (transpressional senso lato), occasionally compressional, regime from the <span class="hlt">southern</span> Mérida Andes on the southwest to the gulf of Paria in the east. Significant changes in direction of the maximum horizontal stress (σH = σ1) can be established along it though. The σ1 direction varies progressively from nearly east-west in the <span class="hlt">southern</span> Andes (SW Venezuela) to between NW-SE and NNW-SSE in northwestern Venezuela; this direction remaining constant across northern Venezuela, from Colombia to Trinidad. In addition, the σV defined by inversion of focal mechanisms or by the shape of the stress ellipsoid derived from the Etchecopar et al.'s method better characterize whether the stress regime is transpressional or compressional, or even very rarely trantensional at local scale. The orientation and space variation of this regional stress field in western Venezuela results from the addition of the two major neighbouring interplate maximum horizontal stress orientations (</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNG51A0094M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNG51A0094M"><span>Earthquake Complex Network applied along the Chilean Subduction <span class="hlt">Zone</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martin, F.; Pasten, D.; Comte, D.</p> <p>2017-12-01</p> <p>In recent years the earthquake complex networks have been used as a useful tool to describe and characterize the behavior of seismicity. The earthquake complex network is built in space, dividing the three dimensional space in cubic cells. If the cubic cell contains a hypocenter, we call this cell like a node. The connections between nodes follows the time sequence of the occurrence of the seismic events. In this sense, we have a spatio-temporal configuration of a specific region using the seismicity in that <span class="hlt">zone</span>. In this work, we are applying complex networks to characterize the subduction <span class="hlt">zone</span> along the coast of <span class="hlt">Chile</span> using two networks: a directed and an undirected network. The directed network takes in consideration the time-direction of the connections, that is very important for the connectivity of the network: we are considering the connectivity, ki of the i-th node, like the number of connections going out from the node i and we add the self-connections (if two seismic events occurred successive in time in the same cubic cell, we have a self-connection). The undirected network is the result of remove the direction of the connections and the self-connections from the directed network. These two networks were building using seismic data events recorded by CSN (Chilean Seismological Center) in <span class="hlt">Chile</span>. This analysis includes the last largest earthquakes occurred in Iquique (April 2014) and in Illapel (September 2015). The result for the directed network shows a change in the value of the critical exponent along the Chilean coast. The result for the undirected network shows a small-world behavior without important changes in the topology of the network. Therefore, the complex network analysis shows a new form to characterize the Chilean subduction <span class="hlt">zone</span> with a simple method that could be compared with another methods to obtain more details about the behavior of the seismicity in this region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25052264','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25052264"><span>[Gene geography of <span class="hlt">Chile</span>: regional distribution of American, European and African genetic contributions].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fuentes, Macarena; Pulgar, Iván; Gallo, Carla; Bortolini, María-Cátira; Canizales-Quinteros, Samuel; Bedoya, Gabriel; González-José, Rolando; Ruiz-Linares, Andrés; Rothhammer, Francisco</p> <p>2014-03-01</p> <p>The geographical distribution of genes plays a key role in genetic epidemiology. The Chilean population has three major stem groups (Native American, European and African). To estimate the regional rate of American, European and African admixture of the Chilean population. Forty single nucleotide polymorphisms (SNP´s) which exhibit substantially different frequencies between Amerindian populations (ancestry-informative markers or AIM´s), were genotyped in a sample of 923 Chilean participants to estimate individual genetic ancestry. The American, European and African individual average admixture estimates for the 15 Chilean Regions were relatively homogeneous and not statistically different. However, higher American components were found in northern and <span class="hlt">southern</span> <span class="hlt">Chile</span> and higher European components were found in central <span class="hlt">Chile</span>. A negative correlation between African admixture and latitude was observed. On the average, American and European genetic contributions were similar and significantly higher than the African contribution. Weighted mean American, European and African genetic contributions of 44.34% ± 3 9%, 51.85% ± 5.44% and 3.81% ± 0.45%, were estimated. Fifty two percent of subjects harbor African genes. Individuals with Aymara and Mapuche surnames have an American admixture of 58.64% and 68.33%, respectively. Half of the Chilean population harbors African genes. Participants with Aymara and Mapuche surnames had a higher American genetic contribution than the general Chilean population. These results confirm the usefulness of surnames as a first approximation to determine genetic ancestry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.2969R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.2969R"><span>Fibrous gypsum veins as diffuse features and within fault <span class="hlt">zones</span>: the case study of the Pisco Basin (Ica desert, <span class="hlt">southern</span> Peru)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rustichelli, Andrea; Di Celma, Claudio; Tondi, Emanuele; Baud, Patrick; Vinciguerra, Sergio</p> <p>2016-04-01</p> <p>New knowledge on patterns of fibrous gypsum veins, their genetic mechanisms, deformation style and weathering are provided by a field- and laboratory-based study carried out on the Neogene to Quaternary Pisco Basin sedimentary strata (porous sandstones, siltstones and diatomites) exposed in the Ica desert, <span class="hlt">southern</span> Peru. Gypsum veins vary considerably in dimensions, attitudes and timing and can develop in layered and moderately fractured rocks also in the absence of evaporitic layers. Veins occur both as diffuse features, confined to certain stratigraphic levels, and localised within fault <span class="hlt">zones</span>. Arrays formed by layer-bounded, mutually orthogonal sets of steeply-dipping gypsum veins are reported for the first time. Vein length, height and spacing depend on the thickness of the bed packages in which they are confined. Within fault <span class="hlt">zones</span>, veins are partly a product of faulting but also inherited layer-bounded features along which faults are superimposed. Due to the different petrophysical properties with respect to the parent rocks and their susceptibility to textural and mineralogical modifications, water dissolution and rupture, gypsum veins may have a significant role in geofluid management. Depending on their patterns and grade of physical and chemical alteration, veins may influence geofluid circulation and storage, acting as barriers to flow and possibly also as conduits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70176199','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70176199"><span>Characterizing potentially induced earthquake rate changes in the Brawley Seismic <span class="hlt">Zone</span>, <span class="hlt">southern</span> California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Llenos, Andrea L.; Michael, Andrew J.</p> <p>2016-01-01</p> <p>The Brawley seismic <span class="hlt">zone</span> (BSZ), in the Salton trough of <span class="hlt">southern</span> California, has a history of earthquake swarms and geothermal energy exploitation. Some earthquake rate changes may have been induced by fluid extraction and injection activity at local geothermal fields, particularly at the North Brawley Geothermal Field (NBGF) and at the Salton Sea Geothermal Field (SSGF). We explore this issue by examining earthquake rate changes and interevent distance distributions in these fields. In Oklahoma and Arkansas, where considerable wastewater injection occurs, increases in background seismicity rate and aftershock productivity and decreases in interevent distance were indicative of fluid‐injection‐induced seismicity. Here, we test if similar changes occur that may be associated with fluid injection and extraction in geothermal areas. We use stochastic epidemic‐type aftershock sequence models to detect changes in the underlying seismogenic processes, shown by statistically significant changes in the model parameters. The most robust model changes in the SSGF roughly occur when large changes in net fluid production occur, but a similar correlation is not seen in the NBGF. Also, although both background seismicity rate and aftershock productivity increased for fluid‐injection‐induced earthquake rate changes in Oklahoma and Arkansas, the background rate increases significantly in the BSZ only, roughly corresponding with net fluid production rate increases. Moreover, in both fields the interevent spacing does not change significantly during active energy projects. This suggests that, although geothermal field activities in a tectonically active region may not significantly change the physics of earthquake interactions, earthquake rates may still be driven by fluid injection or extraction rates, particularly in the SSGF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011NHESS..11.3251W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011NHESS..11.3251W"><span>High resolution tsunami inversion for 2010 <span class="hlt">Chile</span> earthquake</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, T.-R.; Ho, T.-C.</p> <p>2011-12-01</p> <p>We investigate the feasibility of inverting high-resolution vertical seafloor displacement from tsunami waveforms. An inversion method named "SUTIM" (small unit tsunami inversion method) is developed to meet this goal. In addition to utilizing the conventional least-square inversion, this paper also enhances the inversion resolution by Grid-Shifting method. A smooth constraint is adopted to gain stability. After a series of validation and performance tests, SUTIM is used to study the 2010 <span class="hlt">Chile</span> earthquake. Based upon data quality and azimuthal distribution, we select tsunami waveforms from 6 GLOSS stations and 1 DART buoy record. In total, 157 sub-faults are utilized for the high-resolution inversion. The resolution reaches 10 sub-faults per wavelength. The result is compared with the distribution of the aftershocks and waveforms at each gauge location with very good agreement. The inversion result shows that the source profile features a non-uniform distribution of the seafloor displacement. The highly elevated vertical seafloor is mainly concentrated in two areas: one is located in the northern part of the epicentre, between 34° S and 36° S; the other is in the <span class="hlt">southern</span> part, between 37° S and 38° S.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=326151','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=326151"><span>Comparison of six green <span class="hlt">chile</span> (capsicum annum) cultivars for efficiency of Etgar® machine harvest</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>As U.S. demand for fresh market green <span class="hlt">chile</span> rises green <span class="hlt">chile</span> acreage in the U.S. is declining due to limited availability and high cost of hand labor to harvest it. Many farmers are opting to grow crops other than green <span class="hlt">chile</span>. Green <span class="hlt">chile</span> is a New Mexican pod-type <span class="hlt">chile</span> that is harvested when the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AAS...22344510K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AAS...22344510K"><span>The Cerro Tololo Inter-American Observatory Summer Student Programs in La Serena, <span class="hlt">Chile</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kaleida, Catherine C.; Smith, C.; Van Der Bliek, N. S.; James, D.</p> <p>2014-01-01</p> <p>The Cerro Tololo Inter-American Observatory (CTIO) offers positions for U.S. and Chilean student interns during the Chilean summer months of January-March (northern winter semester) at the CTIO offices in La Serena, <span class="hlt">Chile</span>. CTIO is part of the National Optical Astronomy Observatory (NOAO) of the United States, focused on the development of astronomy in the <span class="hlt">southern</span> hemisphere. Six undergraduate research assistantships are offered for U.S. physics and astronomy undergraduate students through the NSF-funded Research Experiences for Undergraduates (REU) program. The CTIO-funded Prácticas de Investigación en Astronomía (PIA) program is run concurrently with the REU program, and offers two research assistantships for Chilean undergraduate or 1st or 2nd year masters students, also at the CTIO offices in La Serena, <span class="hlt">Chile</span>. The CTIO REU and PIA programs provide exceptional opportunities for students considering a career in astronomy to engage in substantive research activities with scientists working at the forefront of contemporary astrophysics. Student participants work on specific research projects in close collaboration with members of the CTIO scientific and technical staff, such as galaxy clusters, gravitational lensing, supernovae, planetary nebulae, stellar populations, star clusters, star formation, variable stars and interstellar medium. The CTIO REU and PIA programs emphasize observational techniques and provide opportunities for direct observational experience using CTIO's state-of-the-art telescopes and instrumentation. The programs run for 10 weeks, from mid-January to the end of March. A two-night observing run on Cerro Tololo and a field trip to another observatory in <span class="hlt">Chile</span> are included for students of both programs. These positions are full time, and those selected will receive a modest stipend and subsidized housing on the grounds of the offices of CTIO in La Serena, as well as travel costs to and from La Serena. In addition, the students have the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2010-04-15/pdf/2010-8598.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2010-04-15/pdf/2010-8598.pdf"><span>75 FR 19658 - Preserved Mushrooms From <span class="hlt">Chile</span>, China, India, and Indonesia; Determinations</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2010-04-15</p> <p>... Mushrooms From <span class="hlt">Chile</span>, China, India, and Indonesia; Determinations On the basis of the record \\1\\ developed... antidumping duty orders on preserved mushrooms from <span class="hlt">Chile</span>, China, India, and Indonesia would be likely to lead... Mushrooms from <span class="hlt">Chile</span>, China, India, and Indonesia: Investigation Nos. 731-TA-776-779 (Second Review). By...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2013-07-19/pdf/2013-17388.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2013-07-19/pdf/2013-17388.pdf"><span>78 FR 43141 - Foreign-Trade <span class="hlt">Zone</span> 93-Raleigh-Durham, North Carolina, Authorization of Production Activity...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2013-07-19</p> <p>... DEPARTMENT OF COMMERCE Foreign-Trade <span class="hlt">Zones</span> Board [B-23-2013] Foreign-Trade <span class="hlt">Zone</span> 93--Raleigh-Durham, North Carolina, Authorization of Production Activity, <span class="hlt">Southern</span> Lithoplate, Inc. (Aluminum Printing Plates), Youngsville, North Carolina On March 18, 2013, the Triangle J Council of Governments, grantee of...</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. 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