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Sample records for site nuussuaq peninsula

  1. The Ilugissoq graphite andesite volcano, Nuussuaq, central West Greenland

    NASA Astrophysics Data System (ADS)

    Pedersen, Asger Ken; Larsen, Lotte Melchior

    2006-11-01

    The Ilugissoq graphite andesite volcano on Nuussuaq belongs to the Asuk Member of the Paleocene Vaigat Formation. It is the largest eruption site within the Vaigat Formation and is recognized as the source of the majority of the graphite andesite tuffs found in marine sediments in central Nuussuaq. The volcano consists exclusively of pyroclastic rocks containing a diverse lithic assemblage including sediment xenoliths. The primary pyroclastic fragments consist of magnesian andesite with several weight percent of graphite, which formed when mafic magma established a shallow-level magma reservoir beneath the eruption site, and within older clastic sediments from the Nuussuaq Basin. Magma-modified mudstone is completely dominant in the xenolith assemblage and attests that the graphite andesite originated through prolonged high-temperature assimilation of mudstone. The eruptions took place on a marine shelf consisting of picritic hyaloclastites and subaqueous crater mounds. The volcano consists of four overlapping crater cones aligned along a more than 4 km long NNW-SSE oriented fissure system; two cones barely reached sea level whereas the other two reached up to 200 m above the sea. The morphology of the pyroclastic rocks demonstrates that the volcano evolved through phreatomagmatic activity, which diminished with time. The magma never degassed sufficiently to reach a subaerial lava stage. A moderate primary gas pressure well in excess of 100 bars in the graphite andesite magma facilitated the phreatomagmatic explosions, which created the Ilugissoq volcano. The rocks of the volcano are rich in graphite and contain little or no native iron. In comparison, the contemporaneous and chemically similar subaerial lavas and breccias from Disko and Nuussuaq contain less graphite and more iron. The differences are considered to be due to the extremely pressure-dependent redox-sensitivity of carbon-oxygen equilibria in the range 1 bar (the lavas) to 500 bars (the Ilugissoq

  2. Nuussuaq basin of west Greenland: Subsidence and structural inversion in an Albian - early Tertiary pull-apart basin

    SciTech Connect

    Tankard, A.; Ng, T. Renner, T.

    1996-12-31

    The western margin of Greenland consists of a complex of linked extensional basins which formed during opening of Labrador Sea and Baffin Bay in Albian - early Tertiary time. The Nuussuaq basin, which straddles Nuussuaq peninsula and Disko Island, is onshore. Its sedimentary succession is generally hidden beneath a cover of early Tertiary extrusives. Slim-hole exploration drilling has been based on an integrated basin analysis and magnetotelluric data acquisition. Nuussuaq basin developed at a left-lateral releasing stepover at the end of the Ungava fault, an interplate strike-slip fault zone. SW-directed extension was accommodated by several transfer faults which compartmented the Nuussuaq basin. Although the principal depocenter is only 1500 km{sup 2} in area, interpretation of the magnetotelluric: data shows basin depths greater than 10 km. Persistent overpressuring and the low resistivity lower basin fill are believed to be typical of a young basin which has subsided rapidly. The Cretaceous - lower Tertiary succession is indicative of a restricted, underfilled basin. In contrast, the mid-Paleocene paleogeography was controlled by dextral slip along the basement strike-slip fault zones, broadscale structural inversion of the earlier extensional faults, and widespread volcanism. Catastrophic crestal collapse of inversion anticlines is reflected in sudden incision and rapid filling of a suite of paleovalleys. In Paleocene time, the Nuussuag basin was generally overfilled and dominated by terrestrial depositional systems. Oil seeps are associated with crestal collapse and fracturing of inversion structures. Biomarkers suggest a source rock of Paleocene age.

  3. Nuussuaq basin of west Greenland: Subsidence and structural inversion in an Albian - early Tertiary pull-apart basin

    SciTech Connect

    Tankard, A. ); Ng, T. ) Renner, T. )

    1996-01-01

    The western margin of Greenland consists of a complex of linked extensional basins which formed during opening of Labrador Sea and Baffin Bay in Albian - early Tertiary time. The Nuussuaq basin, which straddles Nuussuaq peninsula and Disko Island, is onshore. Its sedimentary succession is generally hidden beneath a cover of early Tertiary extrusives. Slim-hole exploration drilling has been based on an integrated basin analysis and magnetotelluric data acquisition. Nuussuaq basin developed at a left-lateral releasing stepover at the end of the Ungava fault, an interplate strike-slip fault zone. SW-directed extension was accommodated by several transfer faults which compartmented the Nuussuaq basin. Although the principal depocenter is only 1500 km[sup 2] in area, interpretation of the magnetotelluric: data shows basin depths greater than 10 km. Persistent overpressuring and the low resistivity lower basin fill are believed to be typical of a young basin which has subsided rapidly. The Cretaceous - lower Tertiary succession is indicative of a restricted, underfilled basin. In contrast, the mid-Paleocene paleogeography was controlled by dextral slip along the basement strike-slip fault zones, broadscale structural inversion of the earlier extensional faults, and widespread volcanism. Catastrophic crestal collapse of inversion anticlines is reflected in sudden incision and rapid filling of a suite of paleovalleys. In Paleocene time, the Nuussuag basin was generally overfilled and dominated by terrestrial depositional systems. Oil seeps are associated with crestal collapse and fracturing of inversion structures. Biomarkers suggest a source rock of Paleocene age.

  4. Byers Peninsula: A reference site for coastal, terrestrial and limnetic ecosystem studies in maritime Antarctica

    NASA Astrophysics Data System (ADS)

    Quesada, A.; Camacho, A.; Rochera, C.; Velázquez, D.

    2009-11-01

    This article describes the development of an international and multidisciplinary project funded by the Spanish Polar Programme on Byers Peninsula (Livingston Island, South Shetlands). The project adopted Byers Peninsula as an international reference site for coastal and terrestrial (including inland waters) research within the framework of the International Polar Year initiative. Over 30 scientists from 12 countries and 26 institutions participated in the field work, and many others participated in the processing of the samples. The main themes investigated were: Holocene changes in climate, using both lacustrine sediment cores and palaeo-nests of penguins; limnology of the lakes, ponds, rivers and wetlands; microbiology of microbial mats, ecology of microbial food webs and viral effects on aquatic ecosystems; ornithology, with investigations on a Gentoo penguin rookery ( Pygoscelis papua) as well as the flying ornithofauna; biocomplexity and life cycles of species from different taxonomic groups; analysis of a complete watershed unit from a landscape perspective; and human impacts, specifically the effect of trampling on soil characteristics and biota. Byers Peninsula offers many features as an international reference site given it is one of the largest ice-free areas in the Antarctic Peninsula region, it has a variety of different landscape units, and it hosts diverse aquatic ecosystems. Moreover, the Byers Peninsula is a hotspot for Antarctic biodiversity, and because of its high level of environmental protection, it has been very little affected by human activities. Finally, the proximity to the Spanish polar installations on Livingston Island and the experience derived from previous expeditions to the site make it logistically feasible as a site for ongoing monitoring and research.

  5. Proposed Mars Surveyor 2001 Landing Site at 'Ibishead Peninsula', Southern Elysium Planitia

    NASA Technical Reports Server (NTRS)

    Parker, T. J.; Rice, J. W., Jr.

    1999-01-01

    Our objective is to propose a landing site that the Mars Surveyor 2001 Lander and Curie Rover could go to on Mars that should meet the safety requirements of the spacecraft landing system and optimize surface operations (chiefly driven by power and communications requirements). This site lies between 1.5-3.5 deg S latitude, 195-198 deg W longitude, along a sharp albedo contact between the low-viscosity flow units of southern Elysium Planitia and the eroded highlands margin east of Aeolis Mensae. A relatively-bright "peninsula-like" protrusion of the eroded highlands into the south Elysium plains in this area reminds us of the head of an Ibis, and so we nickname this site "Ibishead Peninsula". This site is designed to be situated as close to a diversity of geologic units within view of the lander instruments. Based on our experience with the visibility of horizon details from the Mars Pathfinder and Viking landing sites, we stipulate that for horizon features to be resolved suitably for detailed study from the lander, they must be no more than several kilometers distant. This is so that diversity can be placed in a geologic context in a region that we feel has some exciting science potential. This objective is different from the Mars Pathfinder requirement to land at a site with a maximum chance for containing a diversity of rocks within a few tens of meters of the lander, which resulted in the selection of a "grab bag" site.

  6. Preliminary Site Classification using the Geologic Map of the Korean Peninsula

    NASA Astrophysics Data System (ADS)

    Kang, S.; Kim, K.; Suk, B.

    2008-12-01

    Studies of the earthquake ground motion consider the soil properties or the bed rock properties in the upper 30 m. The average shear wave velocity in the upper 30 m defined from borehole data is routinely used for classifying the site conditions. However, it is difficult to classify the site condition using the limited borehole data to cover the whole Korean Peninsula. In the study of Lee et al. (2001), site classification of Taiwan was refined using surface geology from the geologic map, geomorphologic data, and borehole data following the guidelines of National Earthquake Reduction Program (NEHRP). Wald and Allen (2007) defined shear wave velocity using slope of topography or gradient in global scale. They also compared their results in the Taiwan region to those proposed by Lee et al. (2001). In this study, we used geologic map, geomorphologic data, estimated average shear wave velocity from slope of topography, and borehole data to define the site conditions of the Korean Peninsula. We compared our results to the borehole data or seismic site condition data which include seismometer locations and ground conditions. There are some differences between our results and seismic site condition data. The discrepancy is attributed to the relatively large scale geologic map (1:250000) which may not include accurate site condition of the regions. Estimated site conditions of the study, however, agree with those from borehole data when a 1-mile buffering distance is applied to geologic condition boundaries. These results provide useful information for the further study of regional hazard estimation, risk management, and other seismological and geotechnical applications.

  7. Impact of medium-distance pollution sources in a Galician suburban site (NW Iberian peninsula).

    PubMed

    Gómez-Carracedo, M P; Andrade, J M; Ballabio, D; Prada-Rodríguez, D; Muniategui-Lorenzo, S; Consonni, V; Piñeiro-Iglesias, M; López-Mahía, P

    2015-04-15

    This work studies airborne quality in a geographical area that has not been investigated broadly: a suburban site nearby A Coruña (Galicia, NW Iberian Peninsula). In contrast to major Spanish cities, the site has Atlantic characteristics: rainy, scarce calm weather and infrequent prolonged sunny periods. The relationships between several gaseous pollutants (NO, NO2, NOx, CO, O3, PM10, PM2.5 and PM1) and their temporal trends (daily, monthly and seasonal) were evaluated. The aim was to unravel whether medium- and long-distance sources were impacting upon the site. Univariate studies focused on factorizing the pollutants according to a codifying factor (wind direction, hour of the day, season and month). Multivariate studies (Varimax-rotated factorial analysis) were done separately on both weekdays and weekends. The intensity of the daily maxima for NO, NO2, NOx and CO was lower during the weekends, with O3 behaving opposite. PM average values agreed with previous historical reports for a rural background station relatively close to the site and they decreased daily between 11:00 and 19:00 h, likely because of the marine breeze. With moderate wind speeds the pollutants were associated to medium-distance pollution sources, mainly the city of A Coruña and a combination of industrial pollution sources (a power plant, a solid waste incinerator and a regional airport). PMID:25616227

  8. New Neanderthal remains from Mani peninsula, Southern Greece: the Kalamakia Middle Paleolithic cave site.

    PubMed

    Harvati, Katerina; Darlas, Andreas; Bailey, Shara E; Rein, Thomas R; El Zaatari, Sireen; Fiorenza, Luca; Kullmer, Ottmar; Psathi, Eleni

    2013-06-01

    The Kalamakia cave, a Middle Paleolithic site on the western coast of the Mani peninsula, Greece, was excavated in 1993-2006 by an interdisciplinary team from the Ephoreia of Paleoanthropology and Speleology (Greek Ministry of Culture) and the Muséum national d'Histoire naturelle (Paris). The site is dated to between ca. 100,000 and >39,000 years BP (Before Present) and has yielded Mousterian lithics, a rich fauna, and human remains from several layers. The latter include 10 isolated teeth, a cranial fragment and three postcranial elements. The remains represent at least eight individuals, two of them subadults, and show both carnivore and anthropogenic modifications. They can be identified as Neanderthal on the basis of diagnostic morphology on most specimens. A diet similar to that of Neanderthals from mixed habitat is suggested by our analysis of dental wear (occlusal fingerprint analysis) and microwear (occlusal texture microwear analysis), in agreement with the faunal and palynological analyses of the site. These new fossils significantly expand the Neanderthal sample known from Greece. Together with the human specimens from Lakonis and Apidima, the Kalamakia human remains add to the growing evidence of a strong Neanderthal presence in the Mani region during the Late Pleistocene. PMID:23490263

  9. Thermal regime of active layer at two lithologically contrasting sites on James Ross Island, Antarctic Peninsula.

    NASA Astrophysics Data System (ADS)

    Hrbáček, Filip; Nývlt, Daniel; Láska, Kamil

    2016-04-01

    Antarctic Peninsula region (AP) represents one of the most rapidly warming parts of our planet in the last 50 years. Despite increasing research activities along both western and eastern sides of AP in last decades, there is still a lot of gaps in our knowledge relating to permafrost, active layer and its thermal and physical properties. This study brings new results of active layer monitoring on James Ross Island, which is the largest island in northern AP. Its northern part, Ulu Peninsula, is the largest ice-free area (more than 200 km2) in the region. Due its large area, we focused this study on sites located in different lithologies, which would affect local thermal regime of active layer. Study site (1) at Abernethy Flats area (41 m a.s.l.) lies ~7 km from northern coast. Lithologically is formed by disintegrated Cretaceous calcareous sandstones and siltstones of the Santa Marta Formation. Study site (2) is located at the northern slopes of Berry Hill (56 m a.s.l.), about 0.4 km from northern coastline. Lithology is composed of muddy to intermediate diamictites, tuffaceous siltstones to fine grained sandstones of the Mendel Formation. Data of air temperature at 2 meters above ground and the active layer temperatures at 75 cm deep profiles were obtained from both sites in period 1 January 2012 to 31 December 2014. Small differences were found when comparing mean air temperatures and active temperatures at 5 and 75 cm depth in the period 2012-2014. While the mean air temperatures varied between -7.7 °C and -7.0 °C, the mean ground temperatures fluctuated between -6.6 °C and -6.1 °C at 5 cm and -6.9 °C and -6.0 °C at 75 cm at Abernethy Flats and Berry Hill slopes respectively. Even though ground temperature differences along the profiles weren't pronounced during thawing seasons, the maximum active layer thickness was significantly larger at Berry Hill slopes (80 to 82 cm) than at Abernethy Flats (52 to 64 cm). We assume this differences are affected by

  10. The Punta Lucero Quarry site (Zierbena, Bizkaia): a window into the Middle Pleistocene in the Northern Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Gómez-Olivencia, Asier; Sala, Nohemi; Arceredillo, Diego; García, Nuria; Martínez-Pillado, Virginia; Rios-Garaizar, Joseba; Garate, Diego; Solar, Gonzalo; Libano, Iñaki

    2015-08-01

    The period between the end of the Early Pleistocene and the mid-Middle Pleistocene (roughly between 1.0 and 0.4 Ma BP) is of great interest in Western Europe. It witnessed several climatic oscillations and changes in the fauna, the demise of a hominin species and the appearance of another, along with important cultural and technological changes. Thus, the few available sites with these chronologies is vital to the understanding of the tempo and mode of these changes. Middle Pleistocene sites in the Northern Iberian Peninsula are very rare. Here we present the study of the site found at the Punta Lucero Quarry (Biscay province, Northern Iberian Peninsula), which includes for the first time the complete collection from the site. The fossil association from this site includes several ungulates, such as a Megacerine deer, Cervus elaphus, large bovids (likely both Bos primigenius and Bison sp. are present), Stephanorhinus sp., and carnivores, such as Homotherium latidens, Panthera gombaszoegensis, Canis mosbachensis and Vulpes sp. This association is typical of a middle Middle Pleistocene chronology and would be the oldest macro-mammal site in the Eastern Cantabrian region. This site would likely correspond to a chronology after Mode 1 technological complex and before the arrival of Mode 2 technology in this region. Thus, it offers a glimpse into the paleoecological conditions slightly prior to or contemporaneous with the first Acheulian makers in the northern fringe of the Iberian Peninsula.

  11. Site fidelity in space use by spider monkeys (Ateles geoffroyi) in the Yucatan peninsula, Mexico.

    PubMed

    Ramos-Fernandez, Gabriel; Smith Aguilar, Sandra E; Schaffner, Colleen M; Vick, Laura G; Aureli, Filippo

    2013-01-01

    Animal home ranges may vary little in their size and location in the short term but nevertheless show more variability in the long term. We evaluated the degree of site fidelity of two groups of spider monkeys (Ateles geoffroyi) over a 10- and 13-year period, respectively, in the northeastern Yucatan peninsula, Mexico. We used the Local Convex Hull method to estimate yearly home ranges and core areas (defined as the 60% probability contour) for the two groups. Home ranges varied from 7.7 to 49.6 ha and core areas varied from 3.1 to 9.2 ha. We evaluated the degree of site fidelity by quantifying the number of years in which different areas were used as either home ranges or core areas. Large tracts were used only as home ranges and only for a few years, whereas small areas were used as either core area or home range for the duration of the study. The sum of the yearly core areas coincided partially with the yearly home ranges, indicating that home ranges contain areas used intermittently. Home ranges, and especially core areas, contained a higher proportion of mature forest than the larger study site as a whole. Across years and only in one group, the size of core areas was positively correlated with the proportion of adult males in the group, while the size of home ranges was positively correlated with both the proportion of males and the number of tree species included in the diet. Our findings suggest that spider monkey home ranges are the result of a combination of long-term site fidelity and year-to-year use variation to enable exploration of new resources. PMID:23675427

  12. Site Fidelity in Space Use by Spider Monkeys (Ateles geoffroyi) in the Yucatan Peninsula, Mexico

    PubMed Central

    Ramos-Fernandez, Gabriel; Smith Aguilar, Sandra E.; Schaffner, Colleen M.; Vick, Laura G.; Aureli, Filippo

    2013-01-01

    Animal home ranges may vary little in their size and location in the short term but nevertheless show more variability in the long term. We evaluated the degree of site fidelity of two groups of spider monkeys (Ateles geoffroyi) over a 10- and 13-year period, respectively, in the northeastern Yucatan peninsula, Mexico. We used the Local Convex Hull method to estimate yearly home ranges and core areas (defined as the 60% probability contour) for the two groups. Home ranges varied from 7.7 to 49.6 ha and core areas varied from 3.1 to 9.2 ha. We evaluated the degree of site fidelity by quantifying the number of years in which different areas were used as either home ranges or core areas. Large tracts were used only as home ranges and only for a few years, whereas small areas were used as either core area or home range for the duration of the study. The sum of the yearly core areas coincided partially with the yearly home ranges, indicating that home ranges contain areas used intermittently. Home ranges, and especially core areas, contained a higher proportion of mature forest than the larger study site as a whole. Across years and only in one group, the size of core areas was positively correlated with the proportion of adult males in the group, while the size of home ranges was positively correlated with both the proportion of males and the number of tree species included in the diet. Our findings suggest that spider monkey home ranges are the result of a combination of long-term site fidelity and year-to-year use variation to enable exploration of new resources. PMID:23675427

  13. Comprehensive paleoseismic geological studies in a key site in southwestern Kola Peninsula (Northeast of the Fennoscandian Shield)

    NASA Astrophysics Data System (ADS)

    Nikolaeva, S. B.; Nikonov, A. A.; Shvarev, S. V.; Rodkin, M. V.

    2016-07-01

    This paper considers the results of detailed paleoseismic and geological investigations in a key site in the wall of the Imandra Lake depression (Kola Peninsula Region, Northeast of the Fennoscandian Shield). Study of different groups of paleoseismic deformations developed in the fault zone and the application of new methods and techniques made it possible to identify a large seismotectonic zone characterized by great earthquakes at the end of the Late Glacial and in the Holocene. The investigation data are indicative of the necessity to estimate the seismic potential in the Kola Atomic plant area in a different way.

  14. m b( Pn) Scale for the Korean Peninsula and Site-Dependent Pn Amplification

    NASA Astrophysics Data System (ADS)

    Hong, Tae-Kyung; Lee, Kiwook

    2012-11-01

    The Korean Peninsula is located in the far-eastern Eurasian plate margin where crustal structures vary laterally, causing significant raypath-dependent modulations of crustal phases. The discriminative variations of crustal phases hinder application of conventional local magnitude scales in the continental margin. The mantle-lid phase is less affected by the crustal structures than the crustal phases, providing a better constraint to magnitude estimation. A regional body-wave magnitude scale based on the mantle-lid P wave ( Pn), m b( Pn), is developed for regional events around the Korean Peninsula. The m b( Pn) scale is determined to be m b( Pn) = 0.380 (±0.299) + log A + 2.012 (±0.122) log d, where A is the peak-to-peak Pn amplitude in μm and d is the epicentral distance in km. The m b( Pn) estimates of regional events around the Korean Peninsula are determined. The m b( Pn) estimates are compared with other available magnitude estimates ( m b( Lg), M L). The influence of structures beneath stations on Pn amplification is investigated from inter-station magnitude residuals. A characteristic spatial variation of inter-station magnitude residuals with strengths mostly between -6 and 6 %, but with maximum strengths of ±10 %, is observed. The inter-station magnitude residuals appears to be correlated well with geological and seismic structures in the crust.

  15. Erythema UV-B exposure near the Antarctic Peninsula and comparison with an equatorial site.

    PubMed

    Kirchhoff, V W; Echer, E

    2001-07-01

    Observations of UV-B radiation in the area of the Antarctic Peninsula are described, with the objective to obtain an evaluation of the UV-B enhancements observed during ozone hole episodes, and compare these with equatorial values. The enhancements observed during Southern Hemisphere spring are described in terms of a specific case of enhancement, at the Antarctic peninsula, which has shown a maximum UV-B index of 8.7, in October 1998. The average enhancement between the autumn-unperturbed and spring-perturbed periods results in an UV-B index of 5.4, but with large fluctuations in which much larger indices are produced. These values are compared to indices normally observed in the equatorial region. For measurements obtained with the same kind of instrument at Natal (5.8 degrees S, 35.2 degrees W), the UV-B index varies between 7 and 14, which means that enhanced UV-B indices in the Antarctic Peninsula may become of the same order of magnitude of the lower limit equatorial values. PMID:11470565

  16. Annual survival and site fidelity of Steller's eiders molting along the Alaska Peninsula

    USGS Publications Warehouse

    Flint, P.L.; Petersen, M.R.; Dau, C.P.; Hines, J.E.; Nichols, J.D.

    2000-01-01

    Populations of Steller's eiders (Polysticta stelleri) molting and wintering along the Alaska Peninsula have declined since the 1960's. We captured and marked a large sample of Steller's eiders molting in 2 lagoons along the Alaska Peninsula between 1975-97. We used mark-recapture analysis techniques to estimate annual survival and movement probabilities within and among lagoons for male and female eiders. Estimates of annual survival (??SE) were 0.899 ?? 0.032 for females and 0.765 ?? 0.044 for males. Both sexes showed high rates of fidelity to specific molting locations (>95%) within lagoons; yet we found no evidence that annual probability of survival differed among groups molting in different locations either within or among lagoons. We found weak evidence that annual survival decreased between the periods 1975-81 and 1991-97. The lower survival of males compared to females is unusual for waterfowl and may result in a female-biased sex ratio. We conclude that a decrease in adult survival may have initiated the long-term population decline. Further, a shortage of males may be limiting reproductive potential.

  17. Annual survival and site fidelity of Stellar's Eiders molting along the Alaska Peninsula

    USGS Publications Warehouse

    Flint, P.L.; Petersen, M.R.; Dau, C.P.; Hines, J.E.; Nichols, J.D.

    2000-01-01

    Populations of Steller?s eiders (Polysticta stelleri) molting and wintering along the Alaska Peninsula have declined since the 1960's. We captured and marked a large sample of Steller's eiders molting in 2 lagoons along the Alaska Peninsula between 1975-97. We used mark-recapture analysis techniques to estimate annual survival and movement probabilities within and among lagoons for male and female eiders. Estimates of annual survival (?SE) were 0.899 ? 0.032 for females and 0.765 ? 0.044 for males. Both sexes showed high rates of fidelity to specific molting locations (>95%) within lagoons; yet we found no evidence that annual probability of survival differed among groups molting in different locations either within or among lagoons. We found weak evidence that annual survival decreased between the periods 1975-81 and 1991-97. The lower survival of males compared to females is unusual for waterfowl and may result in a female-biased sex ratio. We conclude that a decrease in adult survival may have initiated the long-term population decline. Further, a shortage of males may be limiting reproductive potential.

  18. Alluvial systems as archives for environmental change at a Hominid site with Oldowan archaeological occurrences: the Homa Peninsula, southwestern Kenya

    NASA Astrophysics Data System (ADS)

    Vincent, Thomas; Whitfield, Elizabeth; Kirby, Jason; Hunt, Christopher; Bishop, Laura; Plummer, Thomas; Ditchfield, Peter

    2016-04-01

    The Homa Peninsula, southwestern Kenya, preserves fossiliferous sedimentary sequences dating to the Plio-Pleistocene. Evidence of hominids inhabiting an open grassland setting and utilising Oldowan tools has been reported here, as well as some of the oldest known traces of hominin activity. Reconstructions of the palaeoenvironment have suggested that alluvial and lake marginal environments on a grassy plain, between wooded slopes and a permanent water body might be plausible. However, these interpretations are based only on field sedimentological analyses and stable isotope analysis at a single site on the peninsula (Kanjera South). It is the aim of this study to utilise a multiproxy approach to develop our understanding of the palaeoenvironmental characteristics here. Sediments will also be characterized at a new site (Nyayanga) through field analyses, as well as through analyses of particle size, siliceous microfossils (diatoms, phytoliths and sponge spicules), pollen and stable isotopes. By utilizing this approach, new insights into the palaeoecology, palaeohydromorphology and palaeoclimate of the locale may be revealed, expanding the limited data available to palaeoanthropological studies of Oldowan occurrences in east Africa. Efforts to refine palaeoenvironmental reconstructions of Kanjera South through particle size analysis have shown that sediments in the lower beds of the sequence are characterised by poor sorting, a bimodal distribution and sand/silty-sand grade material. This suggests rapid deposition and/or a variable hydrological regime and may represent the role of relatively unconfined ephemeral channels in the transportation and deposition of sediments. Fluvial reworking of aeolian sediments, most likely during unconfined flood events may also have occurred.

  19. ALERTES-SC3 Early Warning System prototype for South Iberian Peninsula: on-site approach.

    NASA Astrophysics Data System (ADS)

    Pazos, Antonio; Lopez de Mesa, Mireya; Gallego Carrasco, Javier; Martín Davila, José; Rioja del Rio, Carlos; Morgado, Arturo; Vera, Angel; Ciberia, Angel; Cabieces, Roberto; Strollo, Angelo; Hanka, Winfried; Carranza, Marta

    2016-04-01

    In recent years several Earthquake Early Warning Systems (EEWS) have been developed for different parts of the world. The area between SW Cape St. Vicente and the Strait of Gibraltar is one of the most seismically active zones in the Ibero-Maghrebian region, with predominantly moderate and superficial seismicity, but also big events with associated tsunamis are well documented in the area, like the 1755 Lisbon earthquake. In the frame of the ALERT-ES (2011-2013) and ALERTES-RIM (2014-2016) Spanish projects, the ALERTES-SC3 EEWS, regional approach, prototype has been developed at the Royal Spanish Navy Observatory (ROA) and is being tested in near real time for south Iberia. This prototype, based on the SeisComP3 software package, is largely based on algorithms derived from the analysis of the first seconds of the P wave records. Calculation of several parameters are carried out, mainly the characteristic period (τc) and the displacement peak (Pd), but also the velocity peak (Pv), the maximum period (τPmáx), among others. In order to warm the areas closest to the hypocentre, places located inside the "blind zone", a on-site EEWS has also been developed by ROA and integrated in the ALERTES-SC3 prototype. From the on-site approach, a warm level is declared from one station as a function of the estimated characteristic period (τc) and the displacement Peak (Pd), although the earthquake location and therefore the lead time available remains unknown. This on-site EEWS is being tested in several Western Mediterranean net (WM) stations as ARNO (Arenosillo, Huelva,Spain) or CHAS (Chafarinas island, North Africa, Spain). Also an on-site low cost station is being developed based in low cost accelerometers. In this work the current state of the on-site EEWS developed, its integration in the ALERTES-SC3 EEWS system and the low cost seismic stations are shown.

  20. Peninsula Academies.

    ERIC Educational Resources Information Center

    Raby, Marilyn E.

    1984-01-01

    Describes the Peninsula Academies program developed by the Sequoia (California) Union High School District and 27 local high technology companies to help educationally disadvantaged students break the pattern of low academic achievement, lack of skills, and chronic unemployment. (FL)

  1. Study on the Application of Probabilistic Tsunami Hazard Analysis for the Nuclear Power Plant Site in Korean Peninsula

    NASA Astrophysics Data System (ADS)

    Rhee, H. M.; Kim, M.; Sheen, D. H.; Choi, I. K.

    2014-12-01

    The necessity of study on the tsunami hazard assessment for Nuclear Power Plant (NPP) site was suggested since the event of Fukushima in 2011 had been occurred. It has being emphasized because all of the NPPs in Korean Peninsula are located in coastal region. The tsunami hazard is regarded as the annual exceedance probability for the wave heights. The methodology for analysis of tsunami hazard is based on the seismic hazard analysis. The seismic hazard analysis had been performed by using both deterministic and probabilistic method. Recently, the probabilistic method had been received more attention than the deterministic method because the uncertainties of hazard analysis could be considered by using the logic tree approach. In this study, the probabilistic tsunami hazard analysis for Uljin NPP site was performed by using the information of fault sources which was published by Atomic Energy Society of Japan (AESJ). The wave parameter is the most different parameter with seismic hazard. It could be estimated from the results of tsunami propagation analysis. The TSUNAMI_ver1.0 which was developed by Japan nuclear energy safety organization (JNES), was used for the tsunami simulation. The 80 cases tsunami simulations were performed and then the wave parameters were estimated. For reducing the sensitivity which was encouraged by location of sampling point, the wave parameters were estimated from group of sampling points.The probability density function on the tsunami height was computed by using the recurrence intervals and the wave parameters. And then the exceedance probability distribution was calculated from the probability density function. The tsunami hazards for the sampling groups were calculated. The fractile curves which were shown the uncertainties of input parameters were estimated from the hazards by using the round-robin algorithm. In general, tsunami hazard analysis is focused on the maximum wave heights. But the minimum wave height should be considered

  2. Atmospheric behaviors of polycyclic aromatic hydrocarbons at a Japanese remote background site, Noto peninsula, from 2004 to 2014

    NASA Astrophysics Data System (ADS)

    Tang, Ning; Hakamata, Mariko; Sato, Kousuke; Okada, Yumi; Yang, Xiaoyang; Tatematsu, Michiya; Toriba, Akira; Kameda, Takayuki; Hayakawa, Kazuichi

    2015-11-01

    Total suspended particulates were collected at a Japanese remote background site (Noto Air Monitoring Station; NAMS) on the Noto Peninsula from September 2004 to June 2014. Nine polycyclic aromatic hydrocarbons (PAHs) in the particulates (fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) were determined by HPLC with fluorescence detection. The mean total concentrations of the nine PAHs in the cold season (November to May for the years 2004-2014) was 670 pg m-3 (range 37-4100 pg m-3). The mean total concentration in the warm season (June to October for the same period) was 170 pg m-3 (range 31-960 pg m-3). The atmospheric PAH level at NAMS decreased in recent years, although no significant change was found in the warm season. An analysis of meteorological conditions showed that the atmospheric PAHs at NAMS were long range transported from Northeast China in the cold seasons and were contributed to by Japanese domestic sources in the warm seasons. Lower concentration ratios of reactive PAHs to their isomers at NAMS also supported these results. Activities associated with the Beijing Olympic and Paralympic Games in 2008 and reconstruction after the 2007 Noto Hanto earthquake may have contributed to the yearly variations of atmospheric PAH levels at NAMS during the period 2007-2009. Source control measures implemented by the Chinese and Japanese governments appear to have been effective in decreasing the atmospheric PAH levels at NAMS in recent years.

  3. Data Report: A Search for Deposits of the Late Pliocene Impact of the Eltanin Asteroid in Rise Sediments from the Antarctic Peninsula, Site 1096

    NASA Technical Reports Server (NTRS)

    Kyte, Frank T.

    2003-01-01

    Concentrations of Ir have been measured in 87 sediment samples from Ocean Drilling Program Site 1096 in search of evidence of fallout from the impact of the Eltanin asteroid, which occurred at 2.15 Ma, approx. 1300 km northwest of the site. An additional six samples were measured from a unique sand layer and adjacent sediments that are dated at approx. 1.6 Ma. These 93 sediment samples are all silts and muds that were deposited on a continental rise drift of the Antarctic Peninsula. No evidence of the Eltanin impact deposit was found in this study.

  4. A study of a possible early reindeer domestication site on the Iamal peninsula (Russia) using geoarchaeological methods and lipid biomarkers.

    NASA Astrophysics Data System (ADS)

    Harrault, Loic; Milek, Karen; Dawson, Lorna; Anderson, David

    2016-04-01

    In past centuries, indigenous hunters in Northern Eurasia shifted from being hunters to being herders of reindeer. Even at low human population densities, large reindeer herds can alter the landscape and leave long-term biochemical signatures in the soil. Although indigenous social-ecological systems have been thought to be resilient in space and time, most are considered to be at risk due to climate and socio-economic changes related to anthropogenic activities. This situation calls for a long-term perspective to place human-animal relations in their respective contexts. As an ancient livelihood still practiced across vast areas of Northern Eurasia, reindeer herding is a nexus for feedbacks between humans, animals and environment. The Iarte site, on the Iuribei River in the central part of the Iamal peninsula is thought to be an important site of reindeer domestication dating back to the 12th century due to the enormous quantities of butchered reindeer bones found in recent excavations. The large amount of buried reindeer bones found at the settlement suggests that herds should have stood near the site despite the lack of any architectural remains of corrals or pens. The history of a possible early relation to domesticate reindeer can be described with geoarchaeological methods, including lipid biomarkers, which can indicate the presence of past human and animal activities. Among lipid biomarkers, faecal markers such as stanols and bile acids have already been used in archaeological contexts to identify and distinguish between different species because they are persistent over time and can have a species specific profile. Near the Iarte settlement, we conducted a soil survey and sampling programme and combined geoarchaeological measurements (including electrical conductivity, magnetic susceptibility and elemental analysis) with lipid analysis of soil samples, to identify the potential presence of standing reindeer herds. The different soil layers have been

  5. Light absorption and morphological properties of soot-containing aerosols observed at an East Asian outflow site, Noto Peninsula, Japan

    NASA Astrophysics Data System (ADS)

    Ueda, Sayako; Nakayama, Tomoki; Taketani, Fumikazu; Adachi, Kouji; Matsuki, Atsushi; Iwamoto, Yoko; Sadanaga, Yasuhiro; Matsumi, Yutaka

    2016-03-01

    The coating of black carbon (BC) with inorganic salts and organic compounds can enhance the magnitude of light absorption by BC. To elucidate the enhancement of light absorption of aged BC particles and its relation to the mixing state and morphology of individual particles, we conducted observations of particles at an Asian outflow site in Noto Peninsula, Japan, in the spring of 2013. Absorption and scattering coefficients at 405, 532, and 781 nm and mass concentrations/mixing states of refractory BC in PM2.5 were measured using a three-wavelength photoacoustic soot spectrometer and a single-particle soot photometer (SP2), respectively, after passage through a thermodenuder (TD) maintained at 300 or 400 °C or a bypass line maintained at room temperature (25 °C). The average enhancement factor of BC light absorption due to coating was estimated by comparing absorption coefficients at 781 nm for particles that with and without passing through the TD at 300 °C and was found to be 1.22. The largest enhancements (> 1.30) were observed under high absorption coefficient periods when the air mass was long-range transported from urban areas in China. Aerosol samples were also analyzed using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray analyzer. The morphological features and mixing states of soot-containing particles of four samples collected during the high absorption events were analyzed by comparing microphotographs before and after the evaporation of beam-sensitive materials by irradiation with a high-density electron beam. The majority of the soot in all samples was found as mixed particles with sulfate-containing spherules or as clusters of such spherules. For samples showing high enhancement (> 1.30) of BC light absorption, the TEM showed that the internally mixed soot-containing particles tended to have a more spherical shape and to be thickly coated. The SP2 measurements also suggested that the proportion of thickly coated

  6. Light absorption and morphological properties of soot-containing aerosols observed at an East Asian outflow site, Noto Peninsula, Japan

    NASA Astrophysics Data System (ADS)

    Ueda, S.; Nakayama, T.; Taketani, F.; Adachi, K.; Matsuki, A.; Iwamoto, Y.; Sadanaga, Y.; Matsumi, Y.

    2015-09-01

    The coating of black carbon (BC) with inorganic salts and organic compounds can enhance the magnitude of light absorption by BC. To elucidate the enhancement of light absorption of aged BC particles and its relation to the mixing state and morphology of individual particles, we conducted observations of particles at an Asian outflow site in Noto Peninsula, Japan, in the spring of 2013. Absorption and scattering coefficients at 405, 532, and 781 nm and mass concentrations/mixing states of refractory-BC in PM2.5 were measured using a three-wavelength photoacoustic soot spectrometer and a single-particle soot photometer (SP2), respectively, after passage through a heater maintained at 300 or 400 °C or a bypass line maintained at room temperature (25 °C). The average enhancement of BC light absorption due to coating was estimated by comparing absorption coefficients at 781 nm for particles that with and without passing through the heater and was found to be 22-23 %. The largest enhancements (> 30 %) were observed under high absorption coefficient conditions when the air mass was long-range transported from urban areas in China. Aerosol samples were also analyzed using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray analyzer. The morphological features and mixing states of soot-containing particles of four samples collected during the high absorption coefficient events were analyzed by comparing microphotographs before and after the evaporation of beam-sensitive materials by irradiation with a high density electron beam. The majority of the soot in all samples was found as mixed particles with spherical sulfate or as clusters of sulfate spherules. For samples showing high enhancement (> 30 %) of BC light absorption, TEM showed that the internally mixed soot-containing particles tended to have a more spherical shape and to be embedded into the sulfate. The SP2 measurements also suggested that the proportion of thickly-coated soot was

  7. Long-term temperature monitoring at the biological community site on the Nankai accretionary prism off Kii Peninsula

    NASA Astrophysics Data System (ADS)

    Goto, S.; Hamamoto, H.; Yamano, M.; Kinoshita, M.; Ashi, J.

    2008-12-01

    Nankai subduction zone off Kii Peninsula is one of the most intensively surveyed areas for studies on the seismogenic zone. Multichannel seismic reflection surveys carried out in this area revealed the existence of splay faults that branched from the subduction zone plate boundary [Park et al., 2002]. Along the splay faults, reversal of reflection polarity was observed, indicating elevated pore fluid pressure along the faults. Cold seepages with biological communities were discovered along a seafloor outcrop of one of the splay faults through submersible observations. Long-term temperature monitoring at a biological community site along the outcrop revealed high heat flow carried by upward fluid flow (>180 mW/m2) [Goto et al., 2003]. Toki et al. [2004] estimated upward fluid flow rates of 40-200 cm/yr from chloride distribution of interstitial water extracted from sediments in and around biological community sites along the outcrop. These observation results suggest upward fluid flow along the splay fault. In order to investigate hydrological nature of the splay fault, we conducted long-term temperature monitoring again in the same cold seepage site where Goto et al. [2003] carried out long-term temperature monitoring. In this presentation, we present results of the temperature monitoring and estimate heat flow carried by upward fluid flow from the temperature records. In this long-term temperature monitoring, we used stand-alone heat flow meter (SAHF), a probe-type sediment temperature recorder. Two SAHFs (SAHF-3 and SAHF-4) were used in this study. SAHF-4 was inserted into a bacterial mat, within several meters of which the previous long-term temperature monitoring was conducted. SAHF-3 was penetrated into ordinary sediment near the bacterial mat. The sub-bottom temperature records were obtained for 8 months. The subsurface temperatures oscillated reflecting bottom- water temperature variation (BTV). For sub-bottom temperatures measured with SAHF-3 (outside of

  8. Spatial variability of the active layer thickness at the Limnopolar Lake CALM-S site (Byers Peninsula, Livingston Island, Antarctica) and the role of snow cover.

    NASA Astrophysics Data System (ADS)

    de Pablo, Miguel A.; Molina, Antonio; Ramos, Miguel

    2016-04-01

    Since its establishment in early 2009, thaw depth has been measured in late January - early February at the Limnopolar Lake CALM-S site (A25) in Byers Peninsula, Livingston Island, Antarctica (62°38'59.1''S, 61°06'16.9''W). Ground, surface, and air temperatures have been also measured, as well as snow cover deep, derived from an array of miniature temperature loggers mounted into a wood mast (iButton from Maxim) (Lewcovicz, 2008). Thermal characterization of the active layer has been already done based on this data (de Pablo et al., 2013), as well as the interannual variability (de Pablo et al., 2014) and the snow cover evolution analyses (de Pablo et al., submitted). The results show that permafrost could exist at 120 cm depth, although the active layer is reducing, probably caused by the elongation on the snow cover duration. While the snow cover thickness remains approximately similar each winter, the snow offset delays, reducing the period in which solar radiation could heat the ground. In fact, during the last years, thaw depth was not able to be measured (in spite we visited the area in the approximately the same dates) due to thick snow layer remained covering the CALM-S site. However, we have not yet developed an analysis of the spatial variability of the thaw depth we measured each year, and how it could be conditioned by the ground properties (as slope or grain-size) or external factors, such as snow cover. In order to confirm the effect of the snow cover in the evolution of the active layer thickness, here we analyze the spatial variability of the thaw depth for the entire CALM-S site, and try to correlate it respect to the ground surface characteristics (grain-size, ground patterns, among others), the ground surface temperature and the snow cover thickness. Some of those data were acquired while the surface was visible during Antarctic field trips few years ago, and others (snow cover thickness) was measured by mechanical probing in each node. This

  9. Analysis of aerosol scattering properties measured by a nephelometer at a coastal-rural site in the Atlantic southwest of the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    López, Juan F.; Cachorro, Victoria E.; de Frutos, Angel M.

    2015-09-01

    Aerosol hemispherical scattering and the backscattering coefficients, σsp, σbsc, have been measured using a 3-wavelength (450, 550 and 700 nm) integrating nephelometer over two years (January 2006-May 2008) in the coastal area of the Gulf of Cádiz, in the southwest of the Iberian Peninsula. These coefficients have been carefully analyzed starting with the impact of corrections on the measurements of σsp: i.e., drift calibration constants do not modify the mean value in our data series. However, the selection of dry data (with RH less than 50%) modifies substantially the number of data and the resulting mean value of σsp is now 14% lower, which is compensated when the angular truncation correction is applied. The characterization and features of σsp, σbsc, and the derived parameters αsp (alpha Ångström exponent) and b (the backscatter ratio) has been analyzed, as annual, seasonal and diurnal evolution. A general statistic based on hourly data gives mean values and standard deviation of σsp (500 nm)=48±38 Mm-1 with a median of 38 Mm-1, and σbsc (500 nm)=5.6±3.8 Mm-1 with a median of 4.6 Mm-1. Thus, these values show moderate-low values but with a large range of variation considering the existing measured values over the Iberian Peninsula. The median value of σsp (500 nm) is an indicator that events of high aerosol burden are frequent presenting a substantial influence on the daily averages. The alpha Ångström exponent, αsp, derived from the pairs 450/700 nm gives a mean value 1.35±0.54 with a median of 1.47 and with the most frequent value of 1.7, thus indicating the prevalence of medium size particles but with a significant influence of fine particles. The b ratio has the same value for mean and median, 0.12±0.02, showing a decrease with increasing values of σsp. Annual and daily cycles have been also analyzed showing the complex behaviour of the optical properties at this coastal site where cold and warn periods show very different

  10. Climate and environments during Marine Isotope Stage 11 in the central Iberian Peninsula: the herpetofaunal assemblage from the Acheulean site of Áridos-1, Madrid

    NASA Astrophysics Data System (ADS)

    Blain, Hugues-Alexandre; Santonja, Manuel; Pérez-González, Alfredo; Panera, Joaquin; Rubio-Jara, Susana

    2014-06-01

    The interglacial episodes of the Quaternary Period are currently the focus of a great deal of attention within the scientific community, primarily because they can help us to understand how the climate of the current interglacial may have evolved without human intervention and to assess the impact of these climate changes on ecological systems. In the central Iberian Peninsula, the archaeological site of Áridos-1 (Arganda, Madrid), with numeric dates of 379.7 ± 45 ka obtained by AAR for the upper part of the sedimentological unit of Arganda I, in combination with the evolved state of the small mammals, has been chronologically attributed to Marine Isotope Stage (MIS) 11. Given the diversified faunal assemblages delivered by the 1976 excavations, Áridos-1 is probably one of the best terrestrial candidates for an understanding of the climatic and environmental conditions that prevailed in central Spain during the MIS 11 interglacial. In consequence, the fossil amphibians and squamate reptiles stored in the collections of the Museo Arqueológico Nacional of Madrid have been newly described and quantified in order to apply the mutual climatic range and habitat weighting methods for estimating quantitative data. The Mediterranean climate is shown to have been warmer and wetter than today in central Spain during MIS 11, with the mean annual temperature 1.7 °C higher and mean annual precipitation 223.9 mm higher than at present. The monthly climatic reconstruction shows differences in the distribution of precipitation over the course of the year, with more abundant precipitation during the winter months, at the beginning of spring and at the end of fall (from October to March) and less precipitation than today during the summer months and at the end of spring (from May to August), suggesting stronger rainfall seasonality between winter and summer than currently occurs. Such climate reconstruction is consistent with other European MIS 11 paleoclimatic records. The

  11. Spatial and temporal variation of surface ozone, NO and NO₂ at urban, suburban, rural and industrial sites in the southwest of the Iberian Peninsula.

    PubMed

    Domínguez-López, D; Adame, J A; Hernández-Ceballos, M A; Vaca, F; De la Morena, B A; Bolívar, J P

    2014-09-01

    Surface ozone is one of the most important photochemical pollutants in the low atmosphere, causing damage to human health, vegetation, materials and climate. The weather (high temperatures and high solar radiation), orography (presence of the Guadalquivir valley) and anthropogenic (the cities of Cádiz, Córdoba, Huelva and Seville and two important industrial complexes) characteristics of the southwestern Iberian Peninsula make this region ideal for the formation and accumulation of ozone. To increase the knowledge of ozone behaviour in this area, the monthly, daily and weekly variations of ozone and its precursors, nitrogen oxides (NO(x) = NO + NO2), were analysed over a 4-year period (2003 to 2006). Using the k-means cluster technique, 12 representative stations of five different areas with different ozone behaviour were selected from a total of 29 monitoring sites. This is the first time that the analysis of these atmospheric pollutants has been carried out for the whole area, allowing therefore a complete understanding of the dynamics and the relationships of these compounds in this region. The results showed an opposite behaviour among ozone and NO and NO2 concentrations in urban and suburban zones, marked by maximums of ozone (minimums NO(x)) in spring and summer and minimums (maximums) in autumn and winter. A seasonal behaviour, with lower amplitude, was also observed in rural and industrial areas for ozone concentrations, with the NO and NO2 concentrations remaining at low and similar values during the year in rural zones due to the absence of emission sources in their surroundings. The daily cycles of ozone in urban, suburban and industrial sites registered a maximum value in the early afternoon (14:00-17:00 UTC) while for NOx two peaks were observed, at 7:00-10:00 UTC and 20:00-22:00. In the case of rural stations, no hourly peak of ozone or NO(x) was registered. The weekend effect was studied by using a statistical contrast tests (Student's t

  12. The Yucatan Peninsula

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This MODIS true-color image of the Yucatan Peninsula was acquired from data captured on October 6, 2001. The Peninsula is comprised of several Mexican states, including Yucatan in the north, Quintana Roo to the east, and Campeche to the west. Mexico also shares the Yucatan Peninsula with the countries of Belize and Guatamala, located to the south of these states. Phytoplankton show up as blue-green swirls off the western coast of Yucatan, in the center of the image, mixed in with sediment and other organic matter. Off the eastern coast of the Peninsula, running north and south along the right side of he image, the region's barrier reef is visible. Second only to Australia's Great Barrier Reef in size, the reef spans 180 miles from the northern tip of the Peninsula south into the Gulf of Honduras, and houses over 35 different species of reef-building corals.

  13. Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Temperate and green in the summer, the Kamchatka Peninsula in northeastern Russia freezes over completely in the winter. This true-color image of the Kamchatka Peninsula was acquired on December 12, 2001, by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra spacecraft. The peninsula is surrounded by the Sea of Okhotsk to the west and by the Bering Sea to the east. The ice and snow highlight the stunning valleys and tall peaks of the Sredinnyy Khrebet, which is the volcanic mountain range running down the center of the peninsula. The mountains along the range reach heights of over 3500 meters (11,484 feet). Many of the volcanoes are still active, and ash and volcanic rock has turned the snow a dark gray on the eastern side of the range. The light blue latticework of ridges, valleys, and alluvial fans extending from the center of the range were likely carved out by past and present glaciers and by run-off from spring snowmelt. The small island that extends off of the tip of the peninsula is Ostrov Paramushir (Paramushir Island). Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  14. Peninsula Academies Program.

    ERIC Educational Resources Information Center

    Sequoia Union High School District, Redwood City, CA.

    THE FOLLOWING IS THE FULL TEXT OF THIS DOCUMENT: The Peninsula Academies program helps educationally disadvantaged youth overcome the handicaps of low academic achievement, lack of skills, and chronic unemployment. This is accomplished by providing a high school curriculum that is clearly related to work, training in specific job skills, emphasis…

  15. Ambient levels of volatile organic compounds and criteria pollutants in the most industrialized area of central Iberian Peninsula: intercomparison with an urban site.

    PubMed

    Villanueva, Florentina; Notario, Alberto; Tapia, Araceli; Albaladejo, José; Cabañas, Beatriz; Martínez, Ernesto

    2016-01-01

    This work presents observations of volatile organic compounds (VOCs), including carbonyls, particulate matter 2.5 (PM2.5) (included in the most recent ambient air quality standards because of its harmful effect on health), PM10 and other important pollutants, CO, SO2, NOx and ozone, over the most industrialized area in the central Iberian Peninsula. Nearly two years of data obtained through a mobile laboratory are used for this purpose. Different concentration ratios and correlations were calculated to assess the effect of the anthropogenic or biogenic processes on the observed VOC levels. The diurnal profile for SO2 is different in Puertollano and it does not coincide with the maxima of the other primary pollutants such as benzene, toluene and xylenes (BTX), CO and NO. This behaviour could be attributed to the fact that SO2 mainly comes from industrial activities. However, an impact of the industry on air quality was detected not only by the results obtained for SO2, but also by the toluene/benzene, T/B, ratio (7.5). Finally, correlations between meteorological conditions and pollution distribution have been considered; also, the analysis of the back trajectories together with Spearman correlation coefficients have been carried out to understand the origin and pathway in some events with unusual high pollutant values. PMID:26508360

  16. Evaluation of hot dry rock exploration techniques in the Atlantic Coastal Plain: a test site on the Delmarva Peninsula of Maryland and Virginia

    SciTech Connect

    Not Available

    1981-04-01

    Detailed investigation of a potential Hot Dry Rock (HDR) energy extraction site in the area of Crisfield, Maryland, and Wallops Island, Virginia, (referred to as the Cris-Wall site) was carried out to evaluate HDR exploration techniques in the Atlantic Coastal Plain province. The findings favor the HDR exploration program that is outlined for locating a deep test hole in an area with presumed HDR potential (higher than normal heat flow). Six potential sites for extracting HDR energy have been identified within the Cris-Wall area. Each site is thought to have temperatures at the basement rock surface in excess of 75/sup 0/C and to be at least 1 km away from the nearest fault.

  17. Gulf of Aqaba, Sinai Peninsula

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The Gulf of Aqaba separates the Sinai peninsula from Saudi Arabia in this scene of the Middle East (29.0N, 34.5E) showing the geomorphology and geology of this region including portions of Egypt, Israel, Jordon and Saudi Arabia. A small portion of the Gulf of Suez can be seen on the opposite side of the Sinai peninsula.

  18. Aniakchak Crater, Alaska Peninsula

    USGS Publications Warehouse

    Smith, Walter R.

    1925-01-01

    The discovery of a gigantic crater northwest of Aniakchak Bay (see fig. 11) closes what had been thought to be a wide gap in the extensive series of volcanoes occurring at irregular intervals for nearly 600 miles along the axial line of the Alaska Peninsula and the Aleutian Islands. In this belt there are more active and recently active volcanoes than in all the rest of North America. Exclusive of those on the west side of Cook Inlet, which, however, belong to the same group, this belt contains at least 42 active or well-preserved volcanoes and about half as many mountains suspected or reported to be volcanoes. The locations of some of these mountains and the hot springs on the Alaska Peninsula and the Aleutian Islands are shown on a map prepared by G. A. Waring. Attention has been called to these volcanoes for nearly two centuries, but a record of their activity since the discovery of Alaska is far from being complete, and an adequate description of them as a group has never been written. Owing to their recent activity or unusual scenic beauty, some of the best known of the group are Mounts Katmai, Bogoslof, and Shishaldin, but there are many other beautiful and interesting cones and craters.

  19. Anaglyph, Yucatan Peninsula, Mexico

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This anaglyph (stereoscopic view) of Mexico's Yucatan Peninsula was generated entirely from Shuttle Radar Topography Mission (SRTM) data, and shows a subtle but distinctive indication of the Chicxulub impact crater. Most scientists now agree that this impact was the cause of the Cretatious-Tertiary extinction, the event 65 million years ago that marked the demise of the dinosaurs as well as the majority of life then on Earth. The crater's rim is marked by a shallow semicircular depression arcing about an offshore center point in the upper left of the picture. (The arcing depression is just above the blue line, when viewed with the naked eye.) This depression, or trough, only about 3 to 5 meters (10 - 15 feet) deep and about 5 kilometers (3 miles) wide, was likely caused by collapse of limestone caverns preferentially above the crater rim, resulting in an arcing chain of sinkholes. The limestone that covers most of the Yucatan Peninsula post-dates the impact crater. However, the crater pattern apparently controls the subsidence pattern just enough to show through.

    This anaglyph was created by deriving a shaded relief image from the SRTM data, draping it back over the SRTM elevation model, and then generating two differing perspectives, one for each eye. Illumination is from the north (top). When viewed through special glasses, the anaglyph is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter. The total relief (range of elevations) across this entire image is less than 300 meters (1000 feet).

    Elevation data used in this image were acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM

  20. Antarctic Peninsula and Weddell Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Numerous icebergs are breaking out of the sea ice in the Southern Ocean surrounding the Antarctic Peninsula. This true-color MODIS image from November 13, 2001, shows several icebergs drifting out of the Weddell Sea. The Antarctic Peninsula (left) reaches out into the Drake Passage, which separates the southern tip of South America from Antarctica. Warmer temperatures have cleared a tiny patch of bare ground at the Peninsula's tip. The predominant ocean current in the area is the Antarctic Circumpolar Current ('circum' meaning 'around'), which is also the 'West Wind Drift.' The current is the largest permanent current in the world, and water is moved eastward by westerly winds. Icebergs leaving the Weddell Sea are likely to be moved north and east by the current. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  1. Petroleum geology of Arabian Peninsula

    SciTech Connect

    Billo, S.M.

    1982-05-01

    Petroleum activities in the Arabian Peninsula show new trends in the 1980s. Petroleum exploration is intensified and huge discoveries are anticipated. A giant Jurassic gas field along the coast of the Arabian Gulf discovered recently tops 150 tcf, the largest single reserve ever. Other giant oil fields in the area are undergoing expansion in development and productivity. Today, the Peninsula, with a total area that surpasses one million square miles, produces and exports more oil and gas and has greater reserves than any other area in the world. The excellent reservoir rocks are located in the Jurassic and Cretaceous formations between the Arabian Shield and the Tethyan Seaway. They represent porous and permeable marine cyclical beds sealed by impervious shales and anhydrites. Reservoir sedimentology was affected by 2 orogenies during late Cretaceous and Pliocene time portrayed by the Cratonic area to the southwest and the orthogeosynclinal area to the northeast. The eastern part was little deformed by these movements.

  2. Fires in Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Numerous thermal anomalies were detected on the Kamchatka Peninsula in northeastern Russia in late June and early July by the Moderate Resolution Imaging Spectroradiometer (MODIS). Some of the anomalies (red dots) were fires, but at least one was the result of ongoing volcanic activity at one of the Peninsula's numerous active volcanoes. The erupting volcano, called Sheveluch, can be seen most clearly in the image from July 8, 2002. It is located in the upper right quadrant of the image, and appears as a grayish circular patch amid the surrounding green vegetation. In its center is a red dot indicating that MODIS detected a thermal signature coming from the restless volcano. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  3. The Spatial Coherence of Interannual Temperature Variations in the Antarctic Peninsula

    NASA Technical Reports Server (NTRS)

    King, John C.; Comiso, Josefino C.; Koblinsky, Chester J. (Technical Monitor)

    2002-01-01

    Over 50 years of observations from climate stations on the west coast of the Antarctic Peninsula show that this is a region of extreme interannual variability in near-surface temperatures. The region has also experienced more rapid warming than any other part of the Southern Hemisphere. In this paper we use a new dataset of satellite-derived surface temperatures to define the extent of the region of extreme variability more clearly than was possible using the sparse station data. The region in which satellite surface temperatures correlate strongly with west Peninsula station temperatures is found to be quite small and is largely confined to the seas just west of the Peninsula, with a northward and eastward extension into the Scotia Sea and a southward extension onto the western slopes of Palmer Land. Correlation of Peninsula surface temperatures with surface temperatures over the rest of continental Antarctica is poor confirming that the west Peninsula is in a different climate regime. The analysis has been used to identify sites where ice core proxy records might be representative of variations on the west coast of the Peninsula. Of the five existing core sites examined, only one is likely to provide a representative record for the west coast.

  4. Heavy Metal Contamination in the Taimyr Peninsula, Siberian Arctic

    SciTech Connect

    Allen-Gil, Susan M.; Ford, Jesse; Lasorsa, Brenda K.; Monetti, Matthew; Vlasova, Tamara; Landers, Dixon H.

    2003-01-01

    The Taimyr Peninsula is directly north of the world's largest heavy metal smelting complex (Norilsk, Russia). Despite this proximity, there has been little research to examine the extent of contamination of the Taimyr Peninsula. We analyzed heavy metal concentrations in lichen (Cetraria cucullata), moss (Hylocomium splendens), soils, lake sediment, freshwater fish (Salvelinus alpinus, Lota lota, and Coregonus spp.) and collared lemming (Dicrostonyx torquatus) from 13 sites between 30 and 300 km from Norilsk. Element concentrations were low in both C. cucullata and H. splendens, although concentrations of Al, Fe, Cu, Ni, and Pb were significantly higher than those in Arctic Alaska, probably due to natural differences in the geochemical environments. Inorganic surface soils had significantly higher concentrations of Cd, Zn, Pb, and Mg than inorganic soils at depth, although a lake sediment core from the eastern Taimyr Peninsula indicated no recent enrichment by atmospherically transported elements. Tissue concentrations of heavy metals in fish and lemming were not elevated relative to other Arctic sites. Our results show that the impact of the Norilsk smelting complex is primarily localized rather than regional, and does not extend northward beyond 100 km.

  5. Iberian Peninsula and Balearic Island Bathynellacea (Crustacea, Syncarida) database

    PubMed Central

    Camacho, Ana I.; Dorda, Beatriz A.; Rey, Isabel

    2014-01-01

    Abstract This is the first published database of Bathynellacea. It includes all data of bathynellids (Crustacea, Bathynellacea) collected in the last 64 years (1949 to 2013) on the Iberian Peninsula and Balearic Island. The samples come from groundwater (caves, springs, wells and hyporrheic habitat associated rivers) from both sampling campaigns and occasional sampling conducted throughout the Iberian Peninsula and Balearic Islands. The dataset lists occurrence data of bathynellids distribution, sampling sites (with localities, county and geographic coordinates), taxonomic information (from family to species level) and sampling sources (collector and sampling dates) for all records. The descriptions of new species and species identifications have been carried out by an expert taxonomist (AIC) with 25 years experience in the bathynellids studies (see references). Many of the sampling sites are type localities of endemic species from Iberian Peninsula. The dataset includes 409 samples record corresponding to two families, 12 genera and 58 species, 42 of them formally described plus 16 taxa unpublished and 47 samples in study. All species known from the study area are included, which nearly sum up a quarter of species of Bathynellacea known in the world (250 species). PMID:24693212

  6. Locating and managing peninsulas for nesting ducks

    USGS Publications Warehouse

    Lokemoen, J.T.; Messmer, T.A.

    1994-01-01

    The purpose of this extension bulletin is to guide the management of nesting ducks on peninsulas on public and private lands. Managing peninsulas for ducks is a relatively new strategy that was developed in the grassland region of western North America. Information contained in this bulletin is primarily from studies conducted by biologists working at the Northern Prairie Wildlife Research Center.

  7. Korean peninsula: A northeast Asian security concern. Individual study project

    SciTech Connect

    Blackburn, N.G.

    1993-03-22

    North and South Korea have not responded to the New World Order-that Communism is dead and the Cold War Era is over. When the Berlin Wall collapsed and Germany became one nation, Korea emerged as the only divided country remaining in the world. Today, the Korean Peninsula remains divided by ideology, mutual mistrust of national leadership, the 155-mile DMZ, US military presence, conflicting approaches to national reunification, and the North Korean nuclear issue. Thus, the traditional Cold War animosities and political, economic, military paradigms remain entrenched in a divided Korean peninsula. The US Intelligence Community has identified an extensive nuclear center at Yongbyon, 50 miles north of Pyongyang, North Korea's capital, which appears to be a nuclear reactor and reprocessing site. The threat of a nuclear-armed North Korea is a serious regional security concern that will not be taken lightly by such countries as Japan, China, Russia, South Korea, and the United States.

  8. New evidence of early Neanderthal disappearance in the Iberian Peninsula.

    PubMed

    Galván, Bertila; Hernández, Cristo M; Mallol, Carolina; Mercier, Norbert; Sistiaga, Ainara; Soler, Vicente

    2014-10-01

    The timing of the end of the Middle Palaeolithic and the disappearance of Neanderthals continue to be strongly debated. Current chronometric evidence from different European sites pushes the end of the Middle Palaeolithic throughout the continent back to around 42 thousand years ago (ka). This has called into question some of the dates from the Iberian Peninsula, previously considered as one of the last refuge zones of the Neanderthals. Evidence of Neanderthal occupation in Iberia after 42 ka is now very scarce and open to debate on chronological and technological grounds. Here we report thermoluminescence (TL) and optically stimulated luminescence (OSL) dates from El Salt, a Middle Palaeolithic site in Alicante, Spain, the archaeological sequence of which shows a transition from recurrent to sporadic human occupation culminating in the abandonment of the site. The new dates place this sequence within MIS 3, between ca. 60 and 45 ka. An abrupt sedimentary change towards the top of the sequence suggests a strong aridification episode coinciding with the last Neanderthal occupation of the site. These results are in agreement with current chronometric data from other sites in the Iberian Peninsula and point towards possible breakdown and disappearance of the Neanderthal local population around the time of the Heinrich 5 event. Iberian sites with recent dates (<40 ka) attributed to the Middle Palaeolithic should be revised in the light of these data. PMID:25016565

  9. Geyser Valley on the Kamchatka Peninsula

    NASA Technical Reports Server (NTRS)

    2007-01-01

    On June 2, a devastating mudslide in the world-renowned Geyser Valley on the Kamchatka Peninsula virtually obliterated the natural wonder, forcing the emergency evacuation of visitors and national park personnel. The site, which is the Kamchatka Peninsula's main tourist attraction, consists of some 200 thermal pools created by the area's intense volcanic activity, including about 90 geysers covering an area of four square kilometers (2.5 square miles). It is one of only five sites in the world where the impressive eruptions of steam and boiling-hot water can be found. According to witnesses, a powerful mudslide 1.5 kilometers (one mile) long and 200 meters (600 feet) wide buried more than two-thirds of the valley beneath tens of meters of snow, dirt, trees and boulders (right image), and created a temporary lake submerging more geysers.

    With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

    ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra spacecraft. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

    The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

    The U.S. science team is

  10. Arabian peninsula: zone of ferment

    SciTech Connect

    Stookey, R.W.

    1984-01-01

    The Arabian Peninsula is an area which must be approached in terms of its own values and traditions. The different states, however, present difficulties for even the most well-informed policymaker because the region is not homogeneous. Some of the states are tenuous congeries of tribal and sectarian communities that do not necessarily share the aims of the ruling group. The authors of these six essays consider (1) the economic position of the states, (2) how oil exports affect the economies of the exporting states, (3) how traditional tribal and religious societies react to change, (4) whether their social values are conducive to modernization, and (5) what factors lead to the development of dissent, and how they affect the expression of dissent. Separate abstracts were prepared for two of the essays selected for the Energy Data Base (EDB) and Energy Abstracts for Policy Analysis (EAPA). 23 tables.

  11. Environmental geophysics, offshore Bush River Peninsula, Aberdeen Proving Ground, Maryland

    SciTech Connect

    Miller, S.F.; Kuecher, G.J.; Davies, B.E.

    1995-11-01

    Geophysical studies in shallow waters adjacent to the Bush River Peninsula, Edgewood Area of Aberdeen Proving Ground, Maryland, have delineated the extent of waste disposal sites and established a hydrogeologic framework, which may control contaminant transport offshore. These studies indicate that during the Pleistocene Epoch, alternating stands of high and low sea levels resulted in a complex pattern of shallow channel-fill deposits around the Bush River Peninsula. Ground-penetrating radar studies reveal paleochannels greater than 50 ft deep. Some of the paleochannels are also imaged with marine seismic reflection. Conductivity highs measured with the EM-31 are also indicative of paleochannels. This paleochannel depositional system is environmentally significant because it may control the shallow groundwater flow regime beneath the peninsula. Magnetic, conductivity, and side-scan sonar anomalies outline anthropogenic anomalies in the study area. On the basis of geophysical data, underwater anthropogenic materials do exist in some isolated areas, but large-scale offshore dumping has not occurred in the area studied.

  12. Tropical Depression Alex hits Yucatan Peninsula

    NASA Video Gallery

    NASA's TRMM spacecraft observed this view of Tropical Depression Alex on June 27, 2010 at 2214 UTC (6:14 PM EST). Tropical depression Alex was near the western coast of Mexico's Yucatan Peninsula. ...

  13. QUANTITATIVE PALEOCLIMATE RECONSTRUCTIONS FROM THE MELVILLE PENINSULA, NUNAVUT, CANADA

    NASA Astrophysics Data System (ADS)

    Adams, J. K.; Finkelstein, S. A.

    2009-12-01

    Arctic regions have heightened sensitivity to climatic changes, however regional scale differences exist in the magnitude and timing of response to climatic changes. Modern and paleoclimate data indicate spatial variability in Arctic climates due to local variations in topography, sea ice persistence, or proximity to the coast. Melville Peninsula in the east-central Canadian Arctic is in a modern transitional climate area, with a relatively continental climate to the west and a more maritime climate to the east. Thus, shifting climates may particularly influence the region, and may have affected Thule migration during the past millennium. The presence of Thule archaeological sites and a transitional climate make the Melville Peninsula an area of high importance for paleoclimate reconstructions. Lake sediment cores from two adjacent lakes in the Sarcpa Lake region in the interior Melville Peninsula (68°33’N and 88°17’W, 220 m a.s.l.) were analyzed for diatom assemblages. Diatoms (microscopic algae) were well preserved in these cores and thus, could be used to track paleoclimatic changes. Unofficially named SP02 and SP04, the lakes are 3 and 2.5 ha, respectively. Chronologies were constructed using 210Pb activity and AMS radiocarbon dates. All dates are presented as calendar years before AD 1950. Diatoms appear in SP02 5,900 yrs BP; coupled with high magnetic susceptibility and lower LOI550 in sediment older than 5,900 yrs BP, the appearance of diatoms at this time confirms earlier suggestions of a persistent ice cap on the Peninsula until 6,500 yrs BP. Diatom assemblages are dominated by Fragilarioid species, particularly Staurosira construens var. venter and Staurosirella pinnata. Peak diatom concentration and LOI550 between 4,200 yrs BP and 2,900 yrs BP may indicate the Holocene Thermal Maximum (HTM) on Melville Peninsula. Timing of the HTM on the Peninsula is similar to that from the Baffin Island region to the east. High ratios of Staurosirella pinnata

  14. Shaded Relief, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This topographic image shows the western side of the volcanically active Kamchatka Peninsula, Russia. The data are from the first C-band mapping swath of the Shuttle Radar Topography Mission (SRTM). On the left side are four rivers, which flow northwest to the Sea of Okhotsk. These rivers are, from the south to north, Tigil, Amanina, Voyampolka, and Zhilovaya. The broad, flat floodplains of the rivers are shown in blue. These rivers are important spawning grounds for salmon. In the right side of the image is the Sredinnyy Khrebet, the volcanic mountain range that makes up the 3spine2 of the peninsula. The cluster of hills to the lower right is a field of small dormant volcanoes. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and understand the hazards posed by future eruptions.

    This shaded relief image was generated using topographic data from the Shuttle Radar Topography Mission. A computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. On flatter surfaces, the pattern of light and shadows can reveal subtle features in the terrain. Colors show the elevation as measured by SRTM. Colors range from blue at the lowest elevations to white at the highest elevations. This image contains about 2300 meters (7500 feet) of total relief. Shaded relief maps are commonly used in applications such as geologic mapping and land use planning.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and

  15. Sredinnyy Khrebet, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Kamchatka Peninsula in eastern Russia is shown in this scene created from a preliminary elevation model derived from the first data collected during the Shuttle Radar Topography Mission (SRTM) on February 12, 2000. Sredinnyy Khrebet, the mountain range that makes up the spine of the peninsula, is a chain of active volcanic peaks. Pleistocene and recent glaciers have carved the broad valleys and jagged ridges that are common here. The relative youth of the volcanism is revealed by the topography as infilling and smoothing of the otherwise rugged terrain by lava, ash, and pyroclastic flows, particularly surrounding the high peaks in the south central part of the image. Elevations here range from near sea level up to 2,618 meters (8,590 feet). Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction. Northern slopes appear bright and southern slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow, red, and magenta, to white at the highest elevations. Elevation data used in this image were acquired by the Shuttle Radar Topography Mission (SRTM) aboard Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space

  16. Perspective View, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This perspective view shows the western side of the volcanically active Kamchatka Peninsula, Russia. The data are from the first C-band mapping swath of the Shuttle Radar Topography Mission (SRTM). In the foreground is the broad, flat floodplain of the Amanina River, shown in blue. In background of the image is the Sredinnyy Khrebet, the volcanic mountain range that makes up the 3spine2 of the peninsula. The cluster of hills in the upper right is a field of small dormant volcanoes. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and understand the hazards posed by future eruptions.

    This shaded relief perspective view was generated using topographic data from the Shuttle Radar Topography Mission. A computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. On flatter surfaces, the pattern of light and shadows can reveal subtle features in the terrain. Colors show the elevation as measured by SRTM. Colors range from blue at the lowest elevations to white at the highest elevations. This image contains about 2300 meters (7500 feet) of total relief. To emphasize subtle differences in topography, the relief is exaggerated by a factor of 5.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) and the

  17. [Testaceans (Protozoa: Testacea) in quaternary permafrost sediments of Bykovsky Peninsula, arctic Yakutia].

    PubMed

    Bobrov, A A; Siegert, Ch; Schirrmeister, L; Andreev, A A

    2003-01-01

    The results of the first protozoological study in terms of paleoecology of long-term sediments and buried soils formed in the cryolite zone of northeastern Siberia are discussed. The data on testaceans (Protozoa: Testacea) inhabiting various sites of Bykovsky Peninsula, Laptev Sea coast near estuary of Lena, within the last 53,000 years (late Pleistocene and Holocene). PMID:12712585

  18. Shiveluch Volcano, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2001-01-01

    On the night of June 4, 2001, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) captured this thermal image of the erupting Shiveluch volcano. Located on Russia's Kamchatka Peninsula, Shiveluch rises to an altitude of 2,447 meters (8,028 feet). The active lava dome complex is seen as a bright (hot) area on the summit of the volcano. To the southwest, a second hot area is either a debris avalanche or hot ash deposit. Trailing to the west is a 25-kilometer (15-mile) ash plume, seen as a cold 'cloud' streaming from the summit. At least 60 large eruptions have occurred here during the last 10,000 years; the largest historical eruptions were in 1854 and 1964.

    Because Kamchatka is located along the major aircraft routes between North America/Europe and Asia, this area is constantly monitored for potential ash hazards to aircraft. The area is part of the 'Ring of Fire,' a string of volcanoes that encircles the Pacific Ocean.

    The lower image is the same as the upper, except it has been color-coded: red is hot, light greens to dark green are progressively colder, and gray/black are the coldest areas.

    The image is located at 56.7 degrees north latitude, 161.3 degrees east longitude.

    ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface.

  19. Mitochondrial DNA structure in the Arabian Peninsula

    PubMed Central

    2008-01-01

    Background Two potential migratory routes followed by modern humans to colonize Eurasia from Africa have been proposed. These are the two natural passageways that connect both continents: the northern route through the Sinai Peninsula and the southern route across the Bab al Mandab strait. Recent archaeological and genetic evidence have favored a unique southern coastal route. Under this scenario, the study of the population genetic structure of the Arabian Peninsula, the first step out of Africa, to search for primary genetic links between Africa and Eurasia, is crucial. The haploid and maternally inherited mitochondrial DNA (mtDNA) molecule has been the most used genetic marker to identify and to relate lineages with clear geographic origins, as the African Ls and the Eurasian M and N that have a common root with the Africans L3. Results To assess the role of the Arabian Peninsula in the southern route, we genetically analyzed 553 Saudi Arabs using partial (546) and complete mtDNA (7) sequencing, and compared the lineages obtained with those present in Africa, the Near East, central, east and southeast Asia and Australasia. The results showed that the Arabian Peninsula has received substantial gene flow from Africa (20%), detected by the presence of L, M1 and U6 lineages; that an 18% of the Arabian Peninsula lineages have a clear eastern provenance, mainly represented by U lineages; but also by Indian M lineages and rare M links with Central Asia, Indonesia and even Australia. However, the bulk (62%) of the Arabian lineages has a Northern source. Conclusion Although there is evidence of Neolithic and more recent expansions in the Arabian Peninsula, mainly detected by (preHV)1 and J1b lineages, the lack of primitive autochthonous M and N sequences, suggests that this area has been more a receptor of human migrations, including historic ones, from Africa, India, Indonesia and even Australia, than a demographic expansion center along the proposed southern coastal

  20. Antarctic Peninsula Tidewater Glacier Dynamics

    NASA Astrophysics Data System (ADS)

    Pettit, E. C.; Scambos, T. A.; Haran, T. M.; Wellner, J. S.; Domack, E. W.; Vernet, M.

    2015-12-01

    The northern Antarctic Peninsula (nAP, north of 66°S) is a north-south trending mountain range extending transverse across the prevailing westerly winds of the Southern Ocean resulting in an extreme west-to-east precipitation gradient. Snowfall on the west side of the AP is one to two orders of magnitude higher than the east side. This gradient drives short, steep, fast-flowing glaciers into narrow fjords on the west side, while longer lower-sloping glaciers flow down the east side into broader fjord valleys. This pattern in ice dynamics affects ice-ocean interaction on timescales of decades to centuries, and shapes the subglacial topography and submarine bathymetry on timescales of glacial cycles. In our study, we calculate ice flux for the western and eastern nAP using a drainage model that incorporates the modern ice surface topography, the RACMO-2 precipitation estimate, and recent estimates of ice thinning. Our results, coupled with observed rates of ice velocity from InSAR (I. Joughin, personal communication) and Landsat 8 -derived flow rates (this study), provide an estimate of ice thickness and fjord depth in grounded-ice areas for the largest outlet glaciers. East-side glaciers either still terminate in or have recently terminated in ice shelves. Sedimentary evidence from the inner fjords of the western glaciers indicates they had ice shelves during LIA time, and may still have transient floating ice tongues (tabular berg calvings are observed). Although direct oceanographic evidence is limited, the high accumulation rate and rapid ice flux implies cold basal ice for the western nAP glaciers and therefore weak subglacial discharge relative to eastern nAP glaciers and or other tidewater fjord systems such as in Alaska. Finally, despite lower accumulation rates on the east side, the large elongate drainage basins result in a greater ice flux funneled through fewer deeper glaciers. Due to the relation between ice flux and erosion, these east-side glaciers

  1. Electromagnetic induction studies in the Eyre Peninsula, South Australia

    NASA Astrophysics Data System (ADS)

    Kusi, Robert; White, Antony; Heinson, Graham; Milligan, Peter

    1998-03-01

    Magnetic field fluctuations have been recorded by an array of portable three-component magnetometers at 60 sites across the Eyre Peninsula in South Australia between December 1993 and March 1995. An additional 54 magnetometer data records, collected prior to 1989 and described by Milligan (1989) and Milligan, White & Chamalaun (1989), were included in the analysis. A major conductive feature in the crust, first noted by White & Milligan (1984) as the Eyre Peninsula Anomaly (EPA), is re-examined to assess its continuity to the north of the original arrays and to investigate its relationship with major tectonic features. Magnetic-field time-series were converted to induction arrows in the frequency domain. These induction arrows were initially inverted using the minimum-structure 2-D Occam approach to estimate the electrical conductance of the crust. Following this, thin-sheet forward modelling was used to examine the relationship between the conductance and the dominant tectonic features. The principal results of the modelling are that a narrow conductive feature extends inland from the coast about 160km before terminating, and the conductance is in the range 3000 to 10000S, which decreases inland. A strong correlation exists between the electrical conductance of the Eyre Peninsula and Bouguer gravity anomalies, and in particular the EPA is coincident with a significant Bouguer gravity gradient. There is also good agreement between the locations of the foci of earthquakes of magnitude greater than 4.0 and the EPA. We believe that the anomaly is associated with a geological fracture in the Precambrian upper crust as a result of crustal extension prior to the rifting of Australia from Antarctica in the Jurassic (160Ma).

  2. Orthobunyavirus Antibodies in Humans, Yucatan Peninsula, Mexico

    PubMed Central

    Saiyasombat, Rungrat; Talavera-Aguilar, Lourdes G.; Garcia-Rejon, Julian E.; Farfan-Ale, Jose A.; Machain-Williams, Carlos; Loroño-Pino, Maria A.

    2012-01-01

    We performed a serologic investigation to determine whether orthobunyaviruses commonly infect humans in the Yucatan Peninsula of Mexico. Orthobunyavirus-specific antibodies were detected by plaque reduction neutralization test in 146 (18%) of 823 persons tested. Further studies are needed to determine health risks for humans from this potentially deadly group of viruses. PMID:23017592

  3. The Peninsula Academies. Third Yearly Interim Report.

    ERIC Educational Resources Information Center

    Reynolds, Dorothy F.

    The performance of the Peninsula Academies of Electronics and Computer Technology was assessed for the program's third year of operation in two host schools in the Sequoia Union High School District. Data were collected for approximately 190 Academy students and for a comparison group of non-Academy students. Academies students missed fewer days…

  4. Paleogene sequence on the Alaska Peninsula

    SciTech Connect

    Detterman, R.L.

    1985-04-01

    Paleogene strata are exposed nearly the entire length of the Alaska Peninsula. They include continental and marine volcaniclastic rocks and a thick volcanic sequence. The strata are divided into the Tolstoi, Stepovak, Meshik, and Belkofski (in part) Formations in the southern part of the peninsula, and into the nonmarine clastic West Foreland Formation and the Hemlock Conglomerate in the northern part. The Tolstoi Formation (Paleocene and Eocene), 670-1380 m thick, consists mainly of continental quartz- and chert-rich sandstone and conglomerate, siltstone, and coal. Volcanic clasts and tuffaceous detritus increase in abundance upward. Neritic strata are present as interbeds in the type area. The formation overlies, with a major unconformity, strata ranging in age from Late Jurassic to Late Cretaceous. Partly coeval strata at the north end of the peninsula (West Foreland Formation) are mainly volcanic sandstone and conglomerate. The Stepovak Formation, 1800-2000 m thick, represents two contrasting depositional environments - a lower dark siltstone and sandstone turbidite, about 975 m thick, and a shallow neritic sandstone and siltstone, rich in volcanic material, about 1000 m thick. Locally, the upper part is deltaic sandstone, siltstone, and coal. An abundant metafauna of Eocene and Oligocene age is found in the neritic deposits. A thick coeval volcanic unit, the Meshik Formation, is present in the central part of the peninsula. Andesitic to basaltic lava, breccia, tuff, and lahars, as much as 1500 m thick, have been K-Ar dated at 27-38 m.y. Similar rocks with interbedded sediment at the end of the peninsula are included with the Belkofski Formation.

  5. Ancient Land Routes On The Paximadhi Peninsula, Karystos, Euboea

    NASA Astrophysics Data System (ADS)

    Keller, D.; Hom, E.

    Recent regional surface surveys have placed more focus on rural investigations, but the means of transport and communication within those rural surroundings has not always received adequate attention. The Southern Euboea Exploration Project has undertaken a new phase of research in the Karystos area with the goal of developing a methodology that allows for a more detailed record of the pre-modern land routes. On the Paximadhi peninsula it was possible to identify numerous fragments of suspected ancient routes dating to the Classical and Hellenistic periods. In the majority of cases these fragments were closely associated with adjacent datable ancient sites. By taking into consideration the evidence recorded during the survey it was sometimes possible to propose the extension of these ancient segments and to theorize the directions, lengths, and purposes of ancient networks.

  6. Helium and mercury in the central Seward Peninsula

    SciTech Connect

    Wescott, E.; Ruscetta, C.A.; Foley, D.

    1981-05-01

    The central Seward Peninsula, Alaska, has one Known Geothermal Resource Area (KGRA) at Pilgrim Springs, and has recent volcanic flows, fault systems, topographic and tectonic features which can be explained by a rift model. As part of a geothermal reconnaissance of the area we used helium and mercury concentrations in soil as indicators of geothermal resources. The largest helium concentrations were found in the vicinity of the Pilgrims Springs KGRA, and indicate prime drilling sites. Five profile lines were run across the suspected rift system. Significant helium anomalies were found on several of the traverses, where future exploration might be concentrated. Mercury values showed a great range of variability on the traverses, and seem unreliable as geothermal indicators except in the vicinity of the Pilgrim Springs. Permafrost at the surface resulting in variations in sampling depth may contribute to the mercury variations.

  7. Statistical Analysis of Iberian Peninsula Megaliths Orientations

    NASA Astrophysics Data System (ADS)

    González-García, A. C.

    2009-08-01

    Megalithic monuments have been intensively surveyed and studied from the archaeoastronomical point of view in the past decades. We have orientation measurements for over one thousand megalithic burial monuments in the Iberian Peninsula, from several different periods. These data, however, lack a sound understanding. A way to classify and start to understand such orientations is by means of statistical analysis of the data. A first attempt is done with simple statistical variables and a mere comparison between the different areas. In order to minimise the subjectivity in the process a further more complicated analysis is performed. Some interesting results linking the orientation and the geographical location will be presented. Finally I will present some models comparing the orientation of the megaliths in the Iberian Peninsula with the rising of the sun and the moon at several times of the year.

  8. A Late Holocene Slip Rate Of The North Anatolian Fault, Hersek Peninsula, Izmit Bay, Turkey

    NASA Astrophysics Data System (ADS)

    Kozaci, O.; Altunel, E.; Clahan, K.; Yonlu, O.; Sundermann, S. T.; Lettis, W. R.; Turner, J.; Altekruse, J.; Gumus, I.; Lindvall, S. C.

    2010-12-01

    The Hersek Peninsula has been a strategic site for at least the last two millennia as a result of its location. It extends into Izmit Bay and creates a shortcut for the historical Bagdad Road, an important section of the spice route, between Istanbul (Constantinople) and Iznik (Nicaea). It also controls the entrance of Izmit Bay to Izmit (Nicomedia). Civilizations have been investing in this location by building harbors, fortifications, baths, roads, bridges, aqueducts, and temples. The remnants of these historical structures record evidence for past destruction of both anthropogenic and tectonic origin. From an active tectonics point of view, the Hersek Peninsula is a key locality for understanding seismic hazard in the Marmara Region. It is the last place that the North Anatolian fault can be studied on land before it enters the Marmara Sea and it has experienced strong ground shaking most recently during the M7.4 Izmit earthquake in 1999. Paleoseismic trenching as well as archeoseismologic investigations were recently performed on the Hersek Peninsula for regional and site specific seismic hazard characterization. Our paleoseismic trenches north of the Hersek Lagoon provided fault exposures confirming the location of the North Anatolian fault on the peninsula. Detailed mapping of a 6th century A.D. Byzantine aqueduct offset 14 ± 1 meters along the projection of this fault trace revealed a minimum late Holocene slip rate of 13.6 +1/-3.5 mm yr-1. Rapid fan deposition and subsidence on the delta plain across the Hersek Peninsula has resulted in the relatively recent deposition of several meters of relatively young alluvium and nearshore tidal deposits. Nearly 2 km of trench exposures revealed these deposits were continuous and contain only minor evidence of ground shaking in the form of secondary liquefaction deposits and ground fractures. The lack of primary ground surface rupture evidence in these approximately 300-year-old sediments strongly suggests that the

  9. [[Characterization of the potential geographical distribution area of parrot species in Yucatan Peninsula, Mexico].

    PubMed

    Plasencia Vázquez, Alexis Herminio; Escalona Segura, Griselda

    2014-12-01

    Psittacidae family is one of the most endangered groups in Mexico, since many of their habitats are disappearing. In this research, we characterized the land cover of the potential geographical distribu- tion area of eight extant parrot species within the Yucatan Peninsula. We used the Maximum Entropy algorithm (MaxEnt) and species historical records. To externally validate the models, we used presence and absence records from field observations (2010-2012). To characterize the distribution area, we used the vegetation and land use maps of INEGI Series IV (2007-2010). The models showed a good performance, according to the values of the area under the curve (AUC), which ranged between 0.88-0.95 with the training data and between 0.82-0.91 with test data. We located most of the species in sites where the models predicted their presence. In the Peninsula, over 76% of the parrots' potential geographical distribution area is forested, except for Amazona oratrix. The subhumid tropical forest is the best represented, and the livestock for land use. The most affected species within the Peninsula are: Amazona farinosa and A. oratrix. The Calakmul Biosphere Reserve is the most important area for parrots' protection in the Peninsula. Knowing the characteristics of distribution areas is an essential part in the establishment of parrots' conservation strategies. PMID:25720184

  10. Kuwait Oil Fires, Persian Gulf, Qatar Peninsula

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This view up the Persian Gulf from the Qatar Peninsula into southern Iraq (25.5N, 51.0E) shows an excursion of the smoke plumes from the Kuwait oil fires set during the short Persian Gulf War. Smoke from the fires north of Kuwait City, extends across the Persian Gulf while a larger smoke plume from the southern fires heads into southern Saudi Arabia before beginning to spread out and become more diffuse.

  11. Qatar Peninsula, United Arab Emirates, Persian Gulf

    NASA Technical Reports Server (NTRS)

    1983-01-01

    In this view of the Qatar Peninsula, United Arab Emirates, Persian Gulf, (25.0N, 51.0E) a large oil spill, seen as a large dark toned mass in the water covers much of the surface of the western Persian Gulf. Qatar is one of several of the oil rich United Arab Emirate states. Oil spills and oil pollution of the environment are common occurrances associated with oil tanker loading operations.

  12. Detroit and the Lower Peninsula of Michigan

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This scene displays the southeastern part of Michigan's Lower Peninsula and adjacent Ontario, Canada (43.0N, 84.0W). Detroit can be recognized by its radial pattern of development and sediment plumes in the rivers from the massive industrial activity. The area pockmarked by lakes northwest of Detroit essentially outlines the limits of the Defiance Moraine caused by the stagnation and melting of Ice Age glaciers.

  13. Plants and soil microbes respond to recent warming on the Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Amesbury, M. J.; Royles, J.; Hodgson, D.; Convey, P.; Griffiths, H.; Charman, D.

    2013-12-01

    The Antarctic Peninsula is one of the most rapidly warming regions on Earth, with temperature increases of as much as 3°C recorded since the 1950s. However, the longer-term context of this change is limited and existing records are not suitably located to be able to trace the spatial signature of change over time. This paper will present the first published results from a wider project exploiting peat moss banks spanning 10 degrees of latitude along the Antarctic Peninsula as an archive of late Holocene climate variability. These moss banks are ideal archives for palaeoclimate research as they are well-preserved by freezing, generally monospecific, easily dated by radiocarbon techniques and have sufficiently high accumulation rates to permit decadal resolution. A unique time series of past moss growth and soil microbial activity has been produced from a 150 year old moss bank at Lazarev Bay, Alexander Island, a site at the southern limit of significant plant growth in the Antarctic Peninsula region. We use accumulation rates, cellulose δ13C and fossil testate amoebae to provide an indication of ecosystem productivity. We show that both moss and microbial population growth rates rose rapidly in the 1960s, consistent with temperature change, although recently may have stalled, concurrent with other evidence. The increase in terrestrial plant growth rates and soil microbial activity is unprecedented in the last 150 years. The observed relationship between moss growth, microbial activity and climate at Lazarev Bay suggests that moss bank records have the potential to test the regional expression of temperature variability shown by instrumental data on the Antarctic Peninsula over centennial to millennial timescales, by providing long-term records of summer growth conditions, complementing the more distant and widely dispersed ice core records. As a result, we will conclude by placing the Lazarev Bay record into the wider context of the latest progress of analysis of

  14. Ground-water conditions and quality in the western part of Kenai Peninsula, southcentral Alaska

    USGS Publications Warehouse

    Glass, R.L.

    1996-01-01

    The western part of Kenai Peninsula in southcentral Alaska is bounded by Cook Inlet and the Kenai Mountains. Ground water is the predominant source of water for commercial, industrial, and domestic uses on the peninsula. Mean daily water use in an oil, gas, and chemical processing area north of Kenai is more than 3.5 million gallons. Unconsolidated sediments of glacial and fluvial origin are the most productive aquifers. In the upper (northwestern) peninsula, almost all water used is withdrawn from unconsolidated sediments, which may be as thick as 750 feet. In the lower peninsula, unconsolidated sediments are thinner and are absent on many hills. Water supplies in the lower peninsula are obtained from unconsolidated sediments and bedrock, and a public-water supply in parts of Homer is obtained from Bridge Creek. Throughout the peninsula, ground-water flow occurs primarily as localized flow controlled by permeability of aquifer materials and surface topography. The concentration of constituents analyzed in water from 312 wells indicated that the chemical quality of ground water for human consumption varies from marginal to excellent. Even though the median concentration of dissolved solids is low (152 milligrams per liter), much of the ground water on the peninsula does not meet water-quality regulations for public drinking water established by the U.S. Environmental Protection Agency (USEPA). About 8 percent of wells sampled yielded water having concentrations of dissolved arsenic that exceeded the USEPA primary maximum contaminant level of 50 micrograms per liter. Concentrations of dissolved arsenic were as great as 94 micrograms per liter. Forty-six percent of wells sampled yielded water having concentrations of dissolved iron greater than the USEPA secondary maximum contaminant level of 300 micrograms per liter. Unconsolidated sediments generally yield water having calcium, magnesium, and bicarbonate as its predominant ions. In some areas, ground water at

  15. Pleistocene leopards in the Iberian Peninsula: New evidence from palaeontological and archaeological contexts in the Mediterranean region

    NASA Astrophysics Data System (ADS)

    Sanchis, Alfred; Tormo, Carmen; Sauqué, Víctor; Sanchis, Vicent; Díaz, Rebeca; Ribera, Agustí; Villaverde, Valentín

    2015-09-01

    This study analyses the fossil record of leopards in the Iberian Peninsula. According to the systematic and morphometric features of new remains, identified mainly in Late Pleistocene palaeontological and archaeological sites of the Mediterranean region, they can be attributed to Panthera pardus Linnaeus 1758. The findings include the most complete leopard skeleton from the Iberian Peninsula and one of the most complete in Europe, found in a chasm (Avenc de Joan Guitón) south of Valencia. The new citations and published data are used to establish the leopard's distribution in the Iberian Peninsula, showing its maximum development during the Late Pleistocene. Some references suggest that the species survived for longer here (Lateglacial-Early Holocene) than in other parts of Europe. Finally, the contexts of appearance and origin of leopard remains are described and the processes of interaction with prehistoric human groups are assessed.

  16. Wildfire activity in the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Pereira, Mário; Trigo, Ricardo; Caramelo, Liliana; Rasilla, Domingo

    2010-05-01

    The main objective of this work is to characterize the spatial and temporal variability of the monthly wildfire activity in the Iberian Peninsula trough the first comprehensive assessment of wildfires from both countries (Portugal and Spain). This was made possible for the 28-year long period spanning between 1980 and 2007 using and comparing the Portuguese and Spanish fire databases. We use the Portuguese wildfire database kindly provided by the Forest National Authority which includes information of the fire events recorded between the 1980-2007 period and compute time series of monthly values of burnt area that will be used and the correspondent values from the Spanish database. It should be stressed that the Iberian Peninsula is characterized by very different wildfire regimes. The majority of Iberia being dominated by an intense seasonal peak in the summer, particularly the western (Portugal) and southern (Andalucía) areas. However, the greener provinces in the north present a strong secondary peak in late winter (Galicia) or even a higher activity during the months of February-March (Asturias). Furthermore, we also aim to characterize the weather conditions and the atmospheric circulation associated with high wildfire activity over different areas of the Iberian Peninsula. For this purpose a set of large-scale atmospheric fields was retrieved from the NCEP/NCAR reanalysis. Results obtained for the description of the individual and joint spatial and temporal analysis were based on different methodology, including multivariate statistical analysis (PCA, cluster analysis) and regression techniques, as well as the weather conditions and synoptic patterns characteristic of the months with higher values of burnt area.

  17. Marine pelagic ecosystems: the west Antarctic Peninsula.

    PubMed

    Ducklow, Hugh W; Baker, Karen; Martinson, Douglas G; Quetin, Langdon B; Ross, Robin M; Smith, Raymond C; Stammerjohn, Sharon E; Vernet, Maria; Fraser, William

    2007-01-29

    The marine ecosystem of the West Antarctic Peninsula (WAP) extends from the Bellingshausen Sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. The glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. The ecosystem is divided into three subregions, the continental slope, shelf and coastal regions, each with unique ocean dynamics, water mass and biological distributions. The WAP shelf lies within the Antarctic Sea Ice Zone (SIZ) and like other SIZs, the WAP system is very productive, supporting large stocks of marine mammals, birds and the Antarctic krill, Euphausia superba. Ecosystem dynamics is dominated by the seasonal and interannual variation in sea ice extent and retreat. The Antarctic Peninsula is one among the most rapidly warming regions on Earth, having experienced a 2 degrees C increase in the annual mean temperature and a 6 degrees C rise in the mean winter temperature since 1950. Delivery of heat from the Antarctic Circumpolar Current has increased significantly in the past decade, sufficient to drive to a 0.6 degrees C warming of the upper 300 m of shelf water. In the past 50 years and continuing in the twenty-first century, the warm, moist maritime climate of the northern WAP has been migrating south, displacing the once dominant cold, dry continental Antarctic climate and causing multi-level responses in the marine ecosystem. Ecosystem responses to the regional warming include increased heat transport, decreased sea ice extent and duration, local declines in icedependent Adélie penguins, increase in ice-tolerant gentoo and chinstrap penguins, alterations in phytoplankton and zooplankton community composition and changes in krill recruitment, abundance and availability to predators. The climate

  18. Marine pelagic ecosystems: the West Antarctic Peninsula

    PubMed Central

    Ducklow, Hugh W; Baker, Karen; Martinson, Douglas G; Quetin, Langdon B; Ross, Robin M; Smith, Raymond C; Stammerjohn, Sharon E; Vernet, Maria; Fraser, William

    2006-01-01

    The marine ecosystem of the West Antarctic Peninsula (WAP) extends from the Bellingshausen Sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. The glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. The ecosystem is divided into three subregions, the continental slope, shelf and coastal regions, each with unique ocean dynamics, water mass and biological distributions. The WAP shelf lies within the Antarctic Sea Ice Zone (SIZ) and like other SIZs, the WAP system is very productive, supporting large stocks of marine mammals, birds and the Antarctic krill, Euphausia superba. Ecosystem dynamics is dominated by the seasonal and interannual variation in sea ice extent and retreat. The Antarctic Peninsula is one among the most rapidly warming regions on Earth, having experienced a 2°C increase in the annual mean temperature and a 6°C rise in the mean winter temperature since 1950. Delivery of heat from the Antarctic Circumpolar Current has increased significantly in the past decade, sufficient to drive to a 0.6°C warming of the upper 300 m of shelf water. In the past 50 years and continuing in the twenty-first century, the warm, moist maritime climate of the northern WAP has been migrating south, displacing the once dominant cold, dry continental Antarctic climate and causing multi-level responses in the marine ecosystem. Ecosystem responses to the regional warming include increased heat transport, decreased sea ice extent and duration, local declines in ice-dependent Adélie penguins, increase in ice-tolerant gentoo and chinstrap penguins, alterations in phytoplankton and zooplankton community composition and changes in krill recruitment, abundance and availability to predators. The climate/ecological gradients

  19. The superdeep well of the Kola Peninsula

    SciTech Connect

    Kozlovsky, Y.A.

    1986-01-01

    The structure of continental crusts is a subject of ever increasing importance in the geological sciences. Over 15 years ago, Soviet scientist began drilling a superdeep well on the Kola Peninsula near Murmansk. The well has reached a depth of 12 km and is thereby the deepest well in the world, yielding a vast amount of information on the structure of the continental crust. The geological, geophysical and technological data from the Kola well were initially published in a monographic account entitled ''Kol'skaja sverchglubokaja''. This English translation makes the results available to non-Soviet scientists as well.

  20. Climatic record of the Iberian peninsula from lake Moncortes' sediments

    NASA Astrophysics Data System (ADS)

    Cao, Min; Huguet, Carme; Rull, Valenti; Valero, Blas; Rosell-Mele, Antoni

    2014-05-01

    Climatic record of the Iberian peninsula from lake Moncortes' sediments Min Cao1, Carme Huguet1, Valenti Rull2, Blas L. Valero-Garces3, Antoni Rosell-Melé1,4 1Institut de Ciència i Tecnologia Ambientals (ICTA), Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain; 2Institut de Botanic de Barcelona (CSIC), Passeig del Migdia s/n, 08038, Barcelona, Spain, 3 Instituto Pirenaico de Ecologıa (CSIC), Avda. Montañana 1005, 50059 Zaragoza, Spain, 4Institució Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Catalonia, Spain. The continuing buildup of industrial greenhouse gases in the atmosphere and concomitant increase in global temperatures has made much of the world's society aware that decades to centuries of environmental change lie ahead, and that these will have profound economic, political and societal impacts. The Iberian Peninsula lies in the boundary between tropical and subtropical climates and seems to amplify the climatic signals form the northern hemisphere through both atmospheric and water circulation feedbacks, making it an ideal site to monitor Northern hemisphere climate changes. This extreme sensitivity to climatic changes also makes the Iberian Peninsula extremely vulnerable to future climate changes. This is why understanding sensitivity to climate change and the consequences it will have on both climate and the hydrological cycle is key to implement preventive measures. The aim of our study is to come up with a high resolution quantitative reconstruction of climate variability (temperature, production and precipitation) in the Iberian Peninsula from lake sediments. We also want to establish the relation between those changes and the ones observed in both ice cores from Greenland and paleotemperature records from marine sediments of the continental Iberian margin. For these reasons we sampled a core in Moncortes (42.3N, 0.99E), a lake of karstic origin with an average depth of 25m and an area of 0

  1. 78 FR 10595 - Olympic Peninsula Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-14

    ... Forest Service Olympic Peninsula Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION... Peninsula Resource Advisory Committee (RAC). The RAC will be responsible for reviewing and recommending land... the act be reauthorized this year. RAC members represent a wide range of interests. The...

  2. HEAVY METAL CONTAMINATION IN THE TAIMYR PENINSULA, SIBERIAN ARCTIC

    EPA Science Inventory

    The Taimyr Peninsula is directly north of the world's largest heavy metal smelting complex (Norilsk, Russia). Despite this proximity, there has been little research to examine the extent of contamination of the Taimyr Peninsula, primarily because of the remoteness of this area. W...

  3. Seismic Hazard Assessment for the Baku City and Absheron Peninsula, Azerbaijan

    SciTech Connect

    Babayev, Gulam R.

    2006-03-23

    This paper deals with the seismic hazard assessment for Baku and the Absheron peninsula. The assessment is based on the information on the features of earthquake ground motion excitation, seismic wave propagation (attenuation), and site effect. I analyze active faults, seismicity, soil and rock properties, geological cross-sections, the borehole data of measured shear-wave velocity, lithology, amplification factor of each geological unit, geomorphology, topography, and basic rock and surface ground motions. To estimate peak ground acceleration (PGA) at the surface, PGA at the basic rock is multiplied by the amplification parameter of each surface layers. Quaternary soft deposits, representing a high risk due to increasing PGA values at surface, are studied in detail. For a near-zone target earthquake PGA values are compared to intensity at MSK-64 scale for the Absheron peninsula. The amplification factor for the Baku city is assessed and provides estimations for a level of a seismic motion and seismic intensity of the studied area.

  4. Distribution of recoveries of Steller's Eiders banded on the lower Alaska Peninsula, Alaska

    USGS Publications Warehouse

    Dau, C.P.; Flint, P.L.; Petersen, M.R.

    2000-01-01

    Molting adult Steller's Eiders (Polysticta stelleri) were banded at Izembek Lagoon (1961-1998) and Nelson Lagoon (1995-1997) along the lower Alaska Peninsula to determine breeding distribution and movements. Of 52,985 Steller's Eiders banded, 347 were recovered. The overall low recovery rate may not be indicative of harvest levels but may be due to low reporting rates of bands. Almost all recoveries during summer were from Russia and recovery rates did not differ between sexes. We found no evidence that Steller's Eiders molting in specific locations were more likely to be recovered in specific geographic locations in Russia. Our recoveries suggest that Steller's Eiders molting along the Alaska Peninsula were from Russian breeding sites and from remnant breeding populations in Alaska.

  5. Military confidence building on the Korean Peninsula: possible first steps toward cooperation

    SciTech Connect

    Vannoni, M.

    1997-05-01

    The Korean Peninsula is one of the world`s most tense military confrontational sites. Nearly 2 million North Korean, South Korean, and U.S. troops face each other along the 255-km long military demarcation line. Confidence building measures (CBMs), particularly military ones, that address the security needs of both countries could decrease the danger of conflict and help create an environment where a peace regime might be negotiated. In spite of the present high level of mutual distrust, steps can still be taken to prepare for future development and implementation of CBMs. This paper defines some simple and specific first steps toward CBMs that might be useful on the Korean Peninsula.

  6. The climatology of dust aerosol over the arabian peninsula

    NASA Astrophysics Data System (ADS)

    Shalaby, A.; Rappenglueck, B.; Eltahir, E. A. B.

    2015-01-01

    Dust storms are considered to be a natural hazard over the Arabian Peninsula, since they occur all year round with maximum intensity and frequency in Spring and Summer. The Regional Climate Model version 4 (RegCM4) has been used to study the climatology of atmospheric dust over the Arabian Peninsula from 1999 to 2012. This relatively long simulation period samples the meteorological conditions that determine the climatology of mineral dust aerosols over the Arabian Peninsula. The modeled Aerosol Optical Depth (AOD) has been compared against ground-based observations of three Aerosol Robotic Network (AERONET) stations that are distributed over the Arabian Peninsula and daily space based observations from the Multi-angle Imaging SpectroRadiometer (MISR), the Moderate resolution Imaging SpectroRadimeter (MODIS) and Ozone Monitoring Instrument (OMI). The large scale atmospheric circulation and the land surface response that lead to dust uplifting have been analyzed. While the modeled AOD shows that the dust season extends from March to August with two pronounced maxima, one over the northern Arabian Peninsula in March with AOD equal to 0.4 and one over the southern Arabian Peninsula in July with AOD equal to 0.7, the observations show that the dust season extends from April to August with two pronounced maxima, one over the northern Arabian Peninsula in April with AOD equal to 0.5 and one over the southern Arabian Peninsula in July with AOD equal to 0.5. In spring a high pressure dominates the Arabian Peninsula and is responsible for advecting dust from southern and western part of the Arabian Peninsula to northern and eastern part of the Peninsula. Also, fast developed cyclones in northern Arabian Peninsula are responsible for producing strong dust storms over Iraq and Kuwait. However, in summer the main driver of the surface dust emission is the strong northerly wind ("Shamal") that transport dust from the northern Arabian Peninsula toward south parallel to the

  7. Foraminifera from the Northern Olympic Peninsula, Washington

    USGS Publications Warehouse

    Rau, Weldon W.

    1964-01-01

    Foraminifera from a Tertiary sequence that crops out on the northern part of the Olympic Peninsula, Wash., show stratigraphic and ecologic significance. Forty-two species that are important both to correlations and to ecologic interpretations are illustrated and systematically discussed. The Foraminifera indicate that some of the rocks may be as old as early Eocene. The oldest rocks are tentatively referred to the Penutian stage of Mallory. Other parts of the sequence are referred to the Ulatisian and Narizian stages of Mallory, the Refugian stage of Schenck and Kieinpell, and the Zemorrian and Saucesian stages of Kleinpell. Several short periods of shallow, sheltered sea conditions are suggested by the Foraminifera from several parts of the stratigraphic sequence, but Foraminifera from most of the rocks suggest relatively deep, open-sea conditions. With the exception of shallow, warm-water conditions in rocks of probable middle Eocene age, the Foraminifera suggest that cool-to-cold water temperatures, regardless of depth, prevailed during the deposition of most of the rocks of Tertiary age in the northern Olympic Peninsula.

  8. STS-42 Earth observation of Kamchatka Peninsula

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-42 Earth observation taken aboard Discovery, Orbiter Vehicle (OV) 103, with an electronic still camera (ESC) is of Kamchatka Peninsula in Russia. Mid-afternoon sun projects long shadows from volcanoes on the Kamchatka Peninsula. This flat-topped volcano with the sharp summit crater is Tobachinsky, over 3,085 kilometers high. Its last major eruption was in 1975 and 1976, but it has been very active since the middle of the Sixteenth Century. The shadows cast by the low sunlight brings out the dramatic relief of the volcano as well as the smaller morphologic features. Electronic still photography is a relatively new technology that enables a camera to electronically capture and digitize an image with resolution approaching film quality. The digital images from STS-42 were stored on a disk and brought home with the flight crewmembers for processing. ESC was developed by the JSC Man-Systems Division and this mission's application of it is part of a continuing evolutionary development le

  9. STS-42 Earth observation of Kamchatka Peninsula

    NASA Technical Reports Server (NTRS)

    1992-01-01

    STS-42 Earth observation taken aboard Discovery, Orbiter Vehicle (OV) 103, with an electronic still camera (ESC) is of Kamchatka Peninsula in Russia. Mid-afternoon sun projects long shadows from volcanoes on the Kamchatka Peninsula. This flat-topped volcano with the sharp summit crater is Tobachinsky, over 3,085 kilometers high. Its last major eruption was in 1975 and 1976, but it has been very active since the middle of the Sixteenth Century. The shadows cast by the low sunlight brings out the dramatic relief of the volcano as well as the smaller morphologic features. For example, the small hills in the foreground and behind the central volcano are cinder cones, approximately only 200 meters high. Note the sharp triangular shadow from the conical volcano at right. Electronic still photography is a relatively new technology that enables a camera to electronically capture and digitize an image with resolution approaching film quality. The digital images from STS-42 were stored on a disk

  10. Sinai Peninsula, Shaded Relief and Colored Height

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The Sinai Peninsula, located between Africa and Asia, is a result of those two continents pulling apart from each other. Earth's crust is cracking, stretching, and lowering along the two northern branches of the Red Sea, namely the Gulf of Suez, seen here on the west (left), and the Gulf of Aqaba, seen to the east (right). This color-coded shaded relief image shows the triangular nature of the peninsula, with the coast of the Mediterranean Sea forming the northern side of the triangle. The Suez Canal can be seen as the narrow vertical blue line in the upper left connecting the Red Sea to the Mediterranean.

    The peninsula is divided into three distinct parts; the northern region consisting chiefly of sandstone, plains and hills, the central area dominated by the Tih Plateau, and the mountainous southern region where towering peaks abound. Much of the Sinai is deeply dissected by river valleys, or wadis, that eroded during an earlier geologic period and break the surface of the plateau into a series of detached massifs with a few scattered oases.

    Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction, so that northwest slopes appear bright and southeast slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations.

    Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot

  11. Colored Height and Shaded Relief, Kamchatka Peninsula

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Russia's Kamchatka Peninsula, lying between the Sea of Okhotsk to the west and the Bering Sea and Pacific Ocean to the east, is one of the most active volcanic regions along the Pacific Ring of Fire. It covers an area about the size of Colorado but contains more than 100 volcanoes stretching across the 1000-kilometer-long (620-mile-long) land mass. A dozen or more of these have active vents, with the youngest located along the eastern half of the peninsula. This color-coded shaded relief image, generated with data from the Shuttle Radar Topography Mission (SRTM), shows Kamchatka's volcanic nature to dramatic effect.

    Kliuchevskoi, one of the most active and renowned volcanoes in the world, dominates the main cluster of volcanoes called the Kliuchi group, visible as a circular feature in the center-right of the image. The two other main volcanic ranges lie along northeast-southwest lines, with the older, less active range occupying the center and western half of Kamchatka. The younger, more active belt begins at the southernmost point of the peninsula and continues upward along the Pacific coastline.

    Two visualization methods were combined to produce this image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the north-south direction, so northern slopes appear bright and southern slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and brown to white at the highest elevations.

    The Shuttle Radar Topography Mission flew aboard the Space Shuttle Endeavour, launched on February 11, 2000. The mission used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar that flew twice on the Space Shuttle Endeavour in 1994. The Shuttle Radar Topography Mission was designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60

  12. Airborne pollen trends in the Iberian Peninsula.

    PubMed

    Galán, C; Alcázar, P; Oteros, J; García-Mozo, H; Aira, M J; Belmonte, J; Diaz de la Guardia, C; Fernández-González, D; Gutierrez-Bustillo, M; Moreno-Grau, S; Pérez-Badía, R; Rodríguez-Rajo, J; Ruiz-Valenzuela, L; Tormo, R; Trigo, M M; Domínguez-Vilches, E

    2016-04-15

    Airborne pollen monitoring is an effective tool for studying the reproductive phenology of anemophilous plants, an important bioindicator of plant behavior. Recent decades have revealed a trend towards rising airborne pollen concentrations in Europe, attributing these trends to an increase in anthropogenic CO2 emissions and temperature. However, the lack of water availability in southern Europe may prompt a trend towards lower flowering intensity, especially in herbaceous plants. Here we show variations in flowering intensity by analyzing the Annual Pollen Index (API) of 12 anemophilous taxa across 12 locations in the Iberian Peninsula, over the last two decades, and detecting the influence of the North Atlantic Oscillation (NAO). Results revealed differences in the distribution and flowering intensity of anemophilous species. A negative correlation was observed between airborne pollen concentrations and winter averages of the NAO index. This study confirms that changes in rainfall in the Mediterranean region, attributed to climate change, have an important impact on the phenology of plants. PMID:26803684

  13. Tropospheric ozone variability over the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Kulkarni, Pavan S.; Bortoli, D.; Salgado, R.; Antón, M.; Costa, M. J.; Silva, A. M.

    2011-01-01

    To study tropospheric ozone variability over the Iberian Peninsula (IP), NASA Langley TOR data have been analyzed for the 1979-2005 period. The maximum tropospheric ozone concentration over the entire IP was found in June (˜41 DU) and a minimum in December (˜29 DU). However the maximum tropospheric ozone concentration was found over West Atlantic Coast (WAC) (˜44 DU), followed by Mediterranean Coast (MC) (˜42 DU), North Atlantic Coast (NAC) (˜41 DU), Central Iberian Peninsula (CIP) (˜40 DU) and Pyrenees Mountain Range (PMR) (˜39 DU) during June-July. The high concentration of tropospheric ozone in July over the Atlantic Ocean near IP is due to the presence of Azores anticyclone and related photochemistry and dynamics, and affects the observed higher tropospheric ozone concentration over WAC zone. Strong seasonal cycle in tropospheric ozone concentration has been observed with large variation over NAC (˜49%), followed by WAC (˜48%) and MC (˜41%) compared to CIP and PMR (˜38%) zones. When the data are compared over the IP for the two periods (1979-1993 and 1997-2005), a systematic increase in the number of months with higher tropospheric ozone concentration has been observed during the second period with respect to the first. These increases are almost 8% to 24% over NAC, 6% to 17% over WAC, 5% to 24% over CIP, 6% to 23% over MC and 13% to 18% over PMR, zones. It has been observed that topography, climatology and population density distribution plays a crucial role in the variability of tropospheric ozone concentration over the IP.

  14. Population model for Alaska Peninsula sea otters. Final report

    SciTech Connect

    Eberhardt, L.L.; Siniff, D.B.

    1988-12-31

    This study was conducted to provide a basis for assessing risks of oil spills to sea otter populations along the Alaska Peninsula. The principal efforts were devoted to analyzing the available data on population dynamics. Curves characterizing survivorship and reproduction for sea otters were devised and fitted to several data sets. A detailed review was conducted of methods of assessing population dynamics data, and several new techniques (e.g., bootstrapping) were applied to available data. A simplified model for use with Alaska Peninsula sea otter populations was devised and implemented in a 'spreadsheet' format. Various aspects of model development and data on population size in Alaska Peninsula areas were reviewed.

  15. Fluid Overpressure and Connections to Seismicity, Cascadia Tertiary Accretionary Prism, Olympic Peninsula

    NASA Astrophysics Data System (ADS)

    Rotman, H.; Mattinson, C. G.

    2010-12-01

    Metamorphic dehydration reactions and fluid movement in accretionary prisms have been linked to the recently discovered episodic tremor and slip (ETS) earthquake events along subduction zones, but prior studies lack the detail to effectively test the hypothesis that fluid flow triggers ETS events. I conducted field work along a 52.5 km transect on the Olympic Peninsula metasedimentary accretionary prism of the Cascadia subduction zone, and collected approximately 40 representative samples of sandstone and mudrock that were buried to 6-15 km. This depth range intersects the 10-50 km depth range of ETS events. My objectives are to quantify the water flow recorded in rocks of the Olympic Peninsula via petrographic, whole rock, and isotopic analyses to test the prediction that water release increases at ~10 km depth, creating fluid overpressure needed to trigger seismicity. I calculated that on the Olympic Peninsula 1 km3 of 50% sandstone and 50% mudrock loses ~105 kg H2O/yr during burial from 6-14 km depth, comparable to the values expected from large-scale fluid budget models. Quartz veins that compose 0.5-1% of the Obstruction Peak site (~14 km burial depth) are important records of fluid flow quantity and origin. δ18O values of +11.8‰ to +15.2‰ indicate that vein H2O originated from metamorphic reactions. Flow recorded by 1 km3 of rock containing 0.5-1% quartz veins is >106 kg H2O/yr, comparable to the values 2 × 107 to 2 × 108 kg H2O/yr modeled at compositionally similar subduction zones to produce fluid overpressure conditions. I observed fibrous quartz veins, which also indicate fluid overpressure conditions were reached and support my H2O flow estimates. Therefore, Olympic Peninsula rocks at depths of ~10-14 km record dehydration and fluid overpressure large enough to trigger subduction zone seismicity.

  16. Geomorphic status of regulated rivers in the Iberian Peninsula.

    PubMed

    Lobera, G; Besné, P; Vericat, D; López-Tarazón, J A; Tena, A; Aristi, I; Díez, J R; Ibisate, A; Larrañaga, A; Elosegi, A; Batalla, R J

    2015-03-01

    River regulation by dams modifies flow regimes, interrupts the transfer of sediment through channel networks, and alters downstream bed dynamics, altogether affecting channel form and processes. So far, most studies on the geomorphic impacts of dams are restricted to single rivers, or even single river stretches. In this paper we analyse the geomorphic status of 74 river sites distributed across four large basins in the Iberian Peninsula (i.e. 47 sites located downstream of dams). For this purpose, we combine field data with hydrological data available from water agencies, and analyse historical (1970) and current aerial photographs. In particular, we have developed a Geomorphic Status (GS) index that allows us to assess the physical structure of a given channel reach and its change through time. The GS encompasses a determination of changes in sedimentary units, sediment availability, bar stability and channel flow capacity. Sites are statistically grouped in four clusters based on contrasted physical and climate characteristics. Results emphasise that regulation changes river's flow regime with a generalized reduction of the magnitude and frequency of floods (thus flow competence). This, in addition to the decrease downstream sediment supply, results in the loss of active bars as they are encroached by vegetation, to the point that only reaches with little or no regulation maintain exposed sedimentary deposits. The GS of regulated river reaches is negatively correlated with magnitude of the impoundment (regulation). Heavily impacted reaches present channel stabilization and, in contrast to the hydrological response, the distance and number of tributaries do not reverse the geomorphic impact of the dams. Stabilization limits river dynamics and may contribute to the environmental degradation of the fluvial ecosystem. Overall, results describe the degree of geomorphological alteration experienced by representative Iberian rivers mostly because of regulation

  17. Concentrations and sources of metals in the Antarctic Peninsula aerosol

    SciTech Connect

    Dick, A.L. )

    1991-07-01

    Aerosol samples were collected at a remote site near the east coast of the Antarctic Peninsula during the austral summer of 1984/85. Filter samples were analyzed for Al (as a crustal reference element), marine cations (Na, K, and Ca), heavy metals (Cd, Cu, Pb, and Zn), and sulfate using atomic absorption spectrometry, isotope dilution mass spectrometry, neutron activation analysis, and ion chromatography. Ultraclean sample collection and analysis procedures used to avoid sample contamination are described in detail here. Mean concentrations of heavy metals were found to be: Cd, 0.06 pg m{sup {minus}3}; Cu, 1.0 pg m{sup {minus}3}; Pb, 4.7 pg m{sup {minus}3}; and Zn, 6.1 pg m{sup {minus}3}. These are the lowest concentrations yet determined in the troposphere, but for Pb and Zn they still indicate a significant enrichment over expected crustal concentrations. For these elements, estimated marine and volcanic contributions cannot account for this excess and suggest pollution as the dominant source even at this remote location. For Cd and Cu a dominant anthropogenic source cannot be ruled out, although current estimated of crustal, marine, a volcanic emissions could account for levels determined.

  18. Data Collection in the Arabian Peninsula for Nuclear Explosion Monitoring

    SciTech Connect

    Rodgers, A; Tkalcic, H; Al-Amri, A M S

    2003-07-11

    We report results from the second year of our project (ROA0101-35) to collect seismic event and waveform data recorded in and around the Arabian Peninsula. This effort involves several elements. We have a temporary broadband seismic station operating near the IMS primary array site (PS38) in central Saudi Arabia. We recently installed two temporary broadband stations in the United Arab Emirates (funded by NNSA NA-24 Office of Non-Proliferation & International Security). We are working with King Abdulaziz city for Science and Technology to collect and analyze data from the Saudi National Seismic Network, that consist of 37 digital three-component stations (26 broadband and 11 short-period). We are collaborating with Kuwait Institute for Scientific Research (KISR) to analyze data from their 8 station national seismic network. We participated in the Workshop on Reference Events odnear the Dead Sea Rift held in Paris, France in October 2002. In this paper we present results of these efforts including integration of the raw data into LLNL's Seismic Research Database and preliminary analysis of event locations and source parameters and inference of earth structure.

  19. Heat flow through the sea bottom around the Yucatan Peninsula

    SciTech Connect

    Khutorskoy, M.D.; Kononov, V.I.; Polyak, B.G. ); Fernandez, R. ); Matveev, V.G.; Rot, A.A. )

    1990-02-10

    Heat flow studies were conducted in January-February 1987, off the Atlantic Coast of Mexico on board the R/V Akademik Nikolai Strakhov. Two areas were surveyed, one transecting the Salt Dome Province and the Campeche Canyon, in the Gulf of Mexico, and the other, on the eastern flank of the Yucatan Peninsula. Conductive heat flow through the bottom sediments was determined as the product of vertical temperature gradient and in situ thermal conductivity, measured with a thermal probe using a multithermistor array and real-time processing capabilities. Forward two-dimensional modeling allows one to estimate heat flow variations at both sites from local disturbances and to obtain average heat flow values of 51 mW/m{sup 2} for the transect within the Gulf of Mexico and 38 and 69 mW/m{sup 2} for two basins within the Yucatan area. Sea bottom relief has a predominant effect over other environmental factors in the scatter of heat flow determination in the Gulf of Mexico.

  20. Analysis of air mass trajectories in the northern plateau of the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Pérez, Isidro A.; Sánchez, M. Luisa; García, M. Ángeles; Pardo, Nuria

    2015-11-01

    Air masses reaching the Iberian Peninsula, which is located between two continents and two seas, have been classified. 24-h backward air trajectories were calculated each hour for three years using the METEX model at a site in the centre of the northern plateau of the Iberian Peninsula where the air flow has scarcely been investigated to date. Rather than the usual Euclidean geometry, spherical trigonometry, together with the kernel regression method, was considered to calculate trajectory distances to the site. Numerical indicators allow for an accurate description of the results. Ranges surrounding the site from E to S evidenced a restriction in the movement of the arriving flow. However, the range to the N showed only a slight effect. A noticeable seasonal contrast was observed between winter, whose distances were the greatest, and summer, which displayed the shortest distances. Trajectory clusters, initially not considered in the METEX model, were obtained with different metrics to determine the air mass pathways reaching the site. Five clusters of trajectories were selected so as to easily explain the directions and distances covered. Regional and long range transport were observed in clusters from the NE, NW and SW. The NE cluster presented an orographic deviation and local processes were limited to the SE cluster. Finally, seasonal analysis revealed singular behaviour during autumn, when local processes centred on the N-S direction.

  1. Shaded Relief with Height as Color, Yucatan Peninsula, Mexico

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This shaded relief image of Mexico's Yucatan Peninsula show a subtle, but unmistakable, indication of the Chicxulub impact crater. Most scientists now agree that this impact was the cause of the Cretatious-Tertiary Extinction, the event 65 million years ago that marked the sudden extinction of the dinosaurs as well as the majority of life then on Earth.

    Most of the peninsula is visible here, along with the island of Cozumel off the east coast. The Yucatan is a plateau composed mostly of limestone and is an area of very low relief with elevations varying by less than a few hundred meters (about 500 feet.) In this computer-enhanced image the topography has been greatly exaggerated to highlight a semicircular trough, the darker green arcing line at the upper left corner of the peninsula. This trough is only about 3 to 5 meters (10 to 15 feet) deep and is about 5 km. wide (3 miles), so subtle that if you walked across it you probably would not notice it, and is a surface expression of the crater's outer boundary. Scientists believe the impact, which was centered just off the coast in the Caribbean, altered the subsurface rocks such that the overlying limestone sediments, which formed later and erode very easily, would preferentially erode on the vicinity of the crater rim. This formed the trough as well as numerous sinkholes (called cenotes) which are visible as small circular depressions.

    Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction, so that northwestern slopes appear bright and southeastern slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations.

    For a smaller, annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] (Large

  2. Palaeomagnetic constraints from granodioritic plutons (Jiaodong Peninsula): New insights on Late Mesozoic continental extension in Eastern Asia

    NASA Astrophysics Data System (ADS)

    Charles, Nicolas; Chen, Yan; Augier, Romain; Gumiaux, Charles; Lin, Wei; Faure, Michel; Monié, Patrick; Choulet, Flavien; Wu, Fuyuan; Zhu, Rixiang; Wang, Qingchen

    2011-08-01

    Mechanism and kinematics of the Late Mesozoic continental extension event of Eastern Asia are still debated. In order to better constrain its evolution, two granodioritic plutons of the Jiaodong Peninsula have been chosen as targets for a time-constrained palaeomagnetic study. Indeed, plutons are devoid of visible deformation, did not experience rotation along horizontal axis and are precisely dated by U/Pb and 40Ar/ 39Ar methods. Multidomain (MD) magnetite has been identified as the principal magnetic remanent carrier. The interpolation of existing and new U/Pb and 40Ar/ 39Ar ages revealed that characteristic remanent magnetisation was acquired in a narrow range of 116 ± 2 Ma. Twenty out of 27 sites present stable magnetic directions calculated from high-temperature or high-coercive components. The observations of the solo normal magnetic polarity for this palaeomagnetic collection and of the magnetic remanent age consistent with the Cretaceous Normal Superchron (CNS) argue that the characteristic magnetic remanence may be considered as primary. Detailed field observations of the intrusive relationship between the plutons and country rocks and Anisotropy of Magnetic Susceptibility (AMS) study reveal the absence of the subsequent deformation of plutons, or rigid rotation of plutons along a horizontal axis. Two palaeomagnetic poles have been therefore calculated from these plutons. Among 12 out 15 Cretaceous palaeomagnetic poles, including the two new poles provided by this study, from the Jiaodong Peninsula and on both sides of Tan-Lu and Muping-Jimo faults are statistically consistent. As a result, the Jiaodong Peninsula behaved as a rigid block as internal deformation appears negligible. The remaining three derived poles are probably due to the secular variation or/and the vicinity of fault zones near of the palaeomagnetic sampling site. Thus, they can not be applied to the peninsula-scaled tectonics. Comparison of these time-constrained Cretaceous

  3. 3-D Perspective Kamchatka Peninsula Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This perspective view shows the western side of the volcanically active Kamchatka Peninsula in eastern Russia. The image was generated using the first data collected during the Shuttle Radar Topography Mission (SRTM). In the foreground is the Sea of Okhotsk. Inland from the coast, vegetated floodplains and low relief hills rise toward snow capped peaks. The topographic effects on snow and vegetation distribution are very clear in this near-horizontal view. Forming the skyline is the Sredinnyy Khrebet, the volcanic mountain range that makes up the spine of the peninsula. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and to understand the hazards posed by future eruptions. This image was generated using topographic data from SRTM and an enhanced true-color image from the Landsat 7 satellite. This image contains about 2,400 meters (7,880 feet) of total relief. The topographic expression was enhanced by adding artificial shading as calculated from the SRTM elevation model. The Landsat data was provided by the United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota. SRTM, launched on February 11, 2000, used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. To collect the 3-D SRTM data, engineers added a 60- meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. SRTM collected three dimensional measurements of nearly 80 percent of the Earth's surface. SRTM is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space agencies. Size: 33.3 km (20.6 miles) wide x 136 km (84 miles) coast to skyline. Location: 58.3 deg. North lat., 160 deg. East long. Orientation: Easterly view, 2 degrees

  4. 3-D Perspective View, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This perspective view shows the western side of the volcanically active Kamchatka Peninsula in eastern Russia. The image was generated using the first data collected during the Shuttle Radar Topography Mission (SRTM). In the foreground is the Sea of Okhotsk. Inland from the coast, vegetated floodplains and low relief hills rise toward snow capped peaks. The topographic effects on snow and vegetation distribution are very clear in this near-horizontal view. Forming the skyline is the Sredinnyy Khrebet, the volcanic mountain range that makes up the spine of the peninsula. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and to understand the hazards posed by future eruptions.

    This image was generated using topographic data from SRTM and an enhanced true-color image from the Landsat 7 satellite. This image contains about 2,400 meters (7,880 feet) of total relief. The topographic expression was enhanced by adding artificial shading as calculated from the SRTM elevation model. The Landsat data was provided by the United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota.

    SRTM, launched on February 11, 2000, used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar(SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. To collect the 3-D SRTM data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. SRTM collected three-dimensional measurements of nearly 80 percent of the Earth's surface. SRTM is a cooperative project between NASA, the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Earth Science Enterprise, Washington, D.C.

    Size: 33.3 km (20.6 miles) wide x

  5. Shaded Relief Color Wrapped, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This shaded relief topographic image shows the western side of the volcanically active Kamchatka Peninsula, Russia. The data are from the first C-band mapping swath of the Shuttle Radar Topography Mission (SRTM). On the left side are five rivers, which flow northwest to the Sea of Okhotsk. These rivers are, from the south to north, Tigil, Amanina, Voyampolka, Zhilovaya, and Kakhtana. The broad, flat floodplains of the rivers are shown in yellow. These rivers are important spawning grounds for salmon. In the right side of the image is the Sredinnyy Khrebet, the volcanic mountain range that makes up the 3spine2 of the peninsula. The cluster of hills to the lower right is a field of small dormant volcanoes. High resolution SRTM topographic data will be used by geologists to study how volcanoes form and understand the hazards posed by future eruptions.

    This image was generated using topographic data from the Shuttle Radar Topography Mission. Colors show the elevation as measured by SRTM. Each cycle of colors (from red through green back to red) represents an equal amount of elevation difference (400 meters, or 1300 feet)similar to contour lines on a standard topographic map. This image contains about 2300 meters (7500 feet) of total relief. For the shading, a computer-generated artificial light source illuminates the elevation data to produce a pattern of light and shadows. Slopes facing the light appear bright, while those facing away are shaded. Shaded relief maps are commonly used in applications such as geologic mapping and land use planning.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast

  6. SRTM Anaglyph: Sredinnyy Khrebet, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Kamchatka Peninsula in eastern Russia is shown in this scene created from a preliminary elevation model derived from the first data collected during the Shuttle Radar Topography Mission (SRTM) on February 12, 2000. Sredinnyy Khrebet, the mountain range that makes up the spine of the peninsula, is a chain of active volcanic peaks. Pleistocene and recent glaciers have carved the broad valleys and jagged ridges that are common here. The relative youth of the volcanism is revealed by the topography as infilling and smoothing of the otherwise rugged terrain by lava, ash, and pyroclastic flows, particularly surrounding the high peaks in the south central part of the image. Elevations here range from near sea level up to 2,618 meters (8,590 feet).

    This anaglyph was produced by first shading a preliminary SRTM elevation model. The stereoscopic effect was then created by generating two differing perspectives, one for each eye. When viewed through special glasses, the result is a vertically exaggerated view of Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter.

    Elevation data used in this image was acquired by the Shuttle Radar Topography Mission (SRTM) aboard Space Shuttle Endeavour, launched on February 11,2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on Space Shuttle Endeavour in 1994. SRTM was designed to collect three-dimensional measurements of Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA), the National Imagery and Mapping Agency (NIMA) of the U.S. Department of Defense, and the German and Italian space agencies. It is managed by

  7. Evaporite encrustations and sulphide oxidation products from the southern Antarctic peninsula.

    USGS Publications Warehouse

    Vennum, W.R.

    1980-01-01

    White evaporite encrustations collected from 66 sites scattered over 30 000km2 of S.Antarctic Peninsula are dominantly gypsum and calcite, and subordinate aragonite and thenardite. Natrojarosite occurs as locally developed yellow surface stains on c30% of the white encrustations examined. Water, which forms by the melting of snow blown into cracks in highly fractured rocks by ground blizzards, dissolves soluble ions from minerals in these rocks as it percolates into them. The white encrustations appear to be deposited when this water later rises to the surface by capillary action and evaporates.-from Author Antarctica chemical weathering evaporites sulphide oxidation.

  8. An intersection model for estimating sea otter mortality along the Kenai Peninsula

    USGS Publications Warehouse

    Bodkin, J.L.; Udevitz, M.S.

    1994-01-01

    We developed an intersection model to integrate parameters estimated from three distinct data sets that resulted from the Exxon Valdez oil spill: (1) the distribution, amount, and movements of spilled oil; (2) the distribution and abundance of sea otters along the Kenai Peninsula; and (3) the estimates of site-specific sea otter mortality relative to oil exposure from otters captured for rehabilitation and from collected carcasses. In this chapter, we describe the data sets and provide examples of how they can be used in the model to generate acute loss estimates. We also examine the assumptions required for the model and provide suggestions for improving and applying the model.

  9. Evidence for Bombus occidentalis (Hymenoptera: Apidae) Populations in the Olympic Peninsula, the Palouse Prairie, and Forests of Northern Idaho.

    PubMed

    Rhoades, Paul R; Koch, Jonathan B; Waits, Lisette P; Strange, James P; Eigenbrode, Sanford D

    2016-01-01

    Since the mid-1990s, Bombus occidentalis (Green) has declined from being one of the most common to one of the rarest bumble bee species in the Pacific Northwest of the United States. Although its conservation status is unresolved, a petition to list this species as endangered or threatened was recently submitted to the U.S. Fish and Wildlife Service. To shed light on the conservation situation and inform the U.S. Fish and Wildlife Service decision, we report on the detection and abundance of B. occidentalis following bumble bee collection between 2012 and 2014 across the Pacific Northwest. Collection occurred from the San Juan Islands and Olympic peninsula east to northern Idaho and northeastern Oregon, excluding the arid region in central Washington. B. occidentalis was observed at 23 collection sites out of a total of 234. With the exception of three sites on the Olympic peninsula, all of these were in the southeastern portion of the collection range. PMID:26856817

  10. Evidence for Bombus occidentalis (Hymenoptera: Apidae) Populations in the Olympic Peninsula, the Palouse Prairie, and Forests of Northern Idaho

    PubMed Central

    Rhoades, Paul R.; Koch, Jonathan B.; Waits, Lisette P.; Strange, James P.; Eigenbrode, Sanford D.

    2016-01-01

    Since the mid-1990s, Bombus occidentalis (Green) has declined from being one of the most common to one of the rarest bumble bee species in the Pacific Northwest of the United States. Although its conservation status is unresolved, a petition to list this species as endangered or threatened was recently submitted to the U.S. Fish and Wildlife Service. To shed light on the conservation situation and inform the U.S. Fish and Wildlife Service decision, we report on the detection and abundance of B. occidentalis following bumble bee collection between 2012 and 2014 across the Pacific Northwest. Collection occurred from the San Juan Islands and Olympic peninsula east to northern Idaho and northeastern Oregon, excluding the arid region in central Washington. B. occidentalis was observed at 23 collection sites out of a total of 234. With the exception of three sites on the Olympic peninsula, all of these were in the southeastern portion of the collection range. PMID:26856817

  11. Trichinella pseudospiralis in the Iberian peninsula.

    PubMed

    Zamora, M J; Alvarez, M; Olmedo, J; Blanco, M C; Pozio, E

    2015-06-15

    Nematode worms of the genus Trichinella are zoonotic parasites circulating in most continents, including Europe. In Spain, Trichinella spiralis and Trichinella britovi are highly prevalent in wildlife but seldom in domestic pigs. In Portugal, only T. britovi was documented in wild carnivores. In the period 2006-2013 in Spain, 384 (0.0001%) pigs and 1399 (0.20%) wild boars (Sus scrofa) were positive for Trichinella spp. larvae, which were identified as T. spiralis or T. britovi. In 2014, Trichinella pseudospiralis larvae were isolated from a wild boar hunted in the Gerona province, Cataluña region, North-East of Spain, near the border to France. This is the first report of T. pseudospiralis in the Iberian peninsula, which suggests a broad distribution area of this zoonotic nematode in Europe. Since larvae of this Trichinella species do not encapsulate in the host muscles, they can be detected only by artificial digestion of muscle samples. T. pseudospiralis is the only Trichinella species infecting both mammals and birds. Birds can spread this pathogen over great distances including islands triggering new foci of infections in areas previously considered at low risk for this pathogen. PMID:25913596

  12. Environmental geophysics at the Southern Bush River Peninsula, Aberdeen Proving Ground, Maryland

    SciTech Connect

    Davies, B.E.; Miller, S.F.; McGinnis, L.D.

    1995-05-01

    Geophysical studies have been conducted at five sites in the southern Bush River Peninsula in the Edgewood Area of Aberdeen Proving Ground, Maryland. The goals of the studies were to identify areas containing buried metallic objects and to provide diagnostic signatures of the hydrogeologic framework of the site. These studies indicate that, during the Pleistocene Epoch, alternating stands of high and low sea level resulted in a complex pattern of channel-fill deposits. Paleochannels of various sizes and orientations have been mapped throughout the study area by means of ground-penetrating radar and EM-31 techniques. The EM-31 paleochannel signatures are represented onshore either by conductivity highs or lows, depending on the depths and facies of the fill sequences. A companion study shows the features as conductivity highs where they extend offshore. This erosional and depositional system is environmentally significant because of the role it plays in the shallow groundwater flow regime beneath the site. Magnetic and electromagnetic anomalies outline surficial and buried debris throughout the areas surveyed. On the basis of geophysical measurements, large-scale (i.e., tens of feet) landfilling has not been found in the southern Bush River Peninsula, though smaller-scale dumping of metallic debris and/or munitions cannot be ruled out.

  13. A Study of the San Andreas Slip Rate on the San Francisco Peninsula, California

    NASA Astrophysics Data System (ADS)

    Feigelson, L. M.; Prentice, C.; Grove, K.; Caskey, J.; Ritz, J. F.; Leslie, S.

    2008-12-01

    The most recent large earthquake on the San Andreas Fault (SAF) along the San Francisco Peninsula was the great San Francisco earthquake of April 18, 1906, when a Mw= 7.8 event ruptured 435-470 km of the northern SAF. The slip rate for this segment of the SAF is incompletely known but is important for clarifying seismic hazard in this highly urbanized region. A previous study south of our site has found an average slip rate of 17±4 mm/yr for the late Holocene on the San Francisco Peninsula segment of the SAF. North of the Golden Gate, the SAF joins the San Gregorio Fault with an estimated slip rate of 6 mm/yr. A trench study north of where the two faults join has produced an average late Holocene slip rate of 24±3 mm/yr. To refine slip-rate estimates for the peninsula segment of the SAF, we excavated a trench across the fault where we located an abandoned channel between the San Andreas and Lower Crystal Springs reservoirs. This abandoned channel marks the time when a new channel cut across the SAF; the new channel has since been offset in a right-lateral sense about 20 m. The measured amount of offset and the age of the youngest fluvial sediments in the abandoned channel will yield a slip rate for the San Francisco Peninsula segment of the SAF. We excavated a trench across the abandoned channel and logged the exposed sediments. Our investigation revealed channel-fill alluvium incised and filled by probable debris flow sediments, and a wide fault zone in bedrock, west of the channel deposits. The most prominent fault is probably the strand that moved in 1906. We completed a total-station survey to more precisely measure the offset stream, and to confirm that the fault exposed in the trench aligns with a fence that is known to have been offset 2.8m during the 1906 earthquake. We interpret the debris flow sediments to represent the last phase of deposition prior to abandonment of the old channel. We collected samples for radiocarbon dating, optically stimulated

  14. Seismic Cycle Deformation and Net Coastal Uplift at San Juanillo, Nicoya Peninsula, Costa Rica

    NASA Astrophysics Data System (ADS)

    Butcher, A. J.; Marshall, J.; Morrish, S.; Ritzinger, B.; Wellington, K.

    2011-12-01

    The Nicoya Peninsula, Costa Rica lies ~60 km inboard of the Middle America Trench where the Cocos Plate subducts under the Caribbean Plate at ~9 cm/yr. This outer fore arc peninsula overlies the seismogenic zone along a mature seismic gap, with an estimated recurrence interval of ~50 yr for large megathrust earthquakes. The last major event (M 7.7, 1950) resulted in 1.0-1.5 m of coseismic uplift along the peninsula's central coast. Since then, gradual coastal subsidence has been observed as the plate interface accumulates interseismic strain. While elastic seismic-cycle deformation produces short-term shoreline fluctuations on the Nicoya Peninsula, net tectonic uplift throughout the Quaternary results in long-term coastal emergence and the formation of marine terraces. At San Juanillo, north of Punta Guiones, emergent carbonate beachrock horizons mark former Holocene shorelines with calibrated radiocarbon ages of 0.9-1.8 ka. The position of these deposits on the upper beach face is consistent with net uplift at ~0.5 m/k.y. Tidal erosion and the undermining of beachrock and adjacent cliffs may reflect coastal inundation associated with the current phase of elastic interseismic subsidence. Inland of the beach, two uplifted marine terraces mark former late Quaternary shorelines with inner edge elevations of ~30 m and ~55 m above mean sea level. The ages of these surfaces are estimated at 80 ka and 125 ka respectively, based on correlation with OSL dated terraces ~80 km to the south and the timing of late Pleistocene sea level high stands (Oxygen Isotope Stages 5a-5e). Long-term net uplift at San Juanillo therefore occurs at a rate of 0.3-0.5 m/k.y. This is the highest uplift rate recorded among seven marine terrace study sites along the Nicoya coast, with the exception of the peninsula's southern tip (Cabo Blanco) where accelerated uplift occurs in response to seamount subduction. Since the 1950 Nicoya earthquake, Costa Rica's population and tourism industry have

  15. Late Neogene to Quaternary environmental changes in the Antarctic Peninsula region: evidence from drift sediments

    NASA Astrophysics Data System (ADS)

    Hillenbrand, Claus-Dieter; Ehrmann, Werner

    2005-02-01

    Clay-mineral composition and biogenic opal content in upper Miocene to Quaternary drift sediments recovered at two Ocean Drilling Program (ODP) sites from the continental rise in the Bellingshausen Sea had been analyzed in order to reconstruct the climatic and glacial history of the Antarctic Peninsula. The clay mineral composition at both sites is dominated by smectite, illite, and chlorite, and alternates between a smectite-enriched and a chlorite-enriched assemblage throughout the last 9.3 my. The spatial distribution of clay minerals in Holocene sediments west of the Antarctic Peninsula facilitates the identification of particular source areas, and thus the reconstruction of transport pathways. The similarity to clay mineral variations reported from upper Quaternary sequences suggests that the short-term clay-mineralogical fluctuations in the ODP cores reflect glacial-interglacial cyclicity. Thus, repeated ice advances and retreats in response to a varying size of the Antarctic Peninsula ice cap are likely to have occurred throughout the late Neogene and Quaternary. The clay minerals in the drift sediments exhibit only slight long-term variations, which are caused by local changes in glacial erosion and in supply of source rocks, rather than by major climatic changes. The opal records at the ODP sites are dominated by long-term variations since the late Miocene. We infer that the opal content in the drift sediments, although it is influenced by dissolution in the water column and the sediment column and by the burial with lithogenic detritus, provides a signal of paleoproductivity. Because the annual sea-ice coverage is regarded as the main factor controlling biological productivity, the opal signal helps to reconstruct paleoceanographic changes in the Bellingshausen Sea. Slightly enhanced opal deposition during the late Miocene indicates slightly warmer climatic conditions in the Antarctic Peninsula area than at present. During the early Pliocene, enhanced

  16. Cenozoic epeirogeny of the Arabian Peninsula from drainage modeling

    NASA Astrophysics Data System (ADS)

    Wilson, J. W. P.; Roberts, G. G.; Hoggard, M. J.; White, N. J.

    2014-10-01

    is generally accepted that the Arabian Peninsula has been uplifted by subcrustal processes. Positive residual depth anomalies from oceanic crust in the Red Sea and in the Gulf of Aden suggest that a region surrounding this peninsula is dynamically supported. Admittance calculations, surface wave tomography studies, and receiver function analyses all imply that regional topography is generated and maintained by some combination of mantle convective circulation and lithospheric thickness changes. Despite these significant advances, the spatial and temporal uplift rate history of the Arabian Peninsula is not well known. Here we show that a regional uplift rate history can be obtained by jointly inverting 225 longitudinal river profiles that drain this peninsula. Our strategy assumes that shapes of individual river profiles are controlled by uplift rate history and moderated by erosional processes. We used local measurements of incision rate to calibrate the relevant erosional parameters. In our inverse algorithm, uplift rate is permitted to vary smoothly as a function of space and time but upstream drainage area remains invariant. We also assume that knickzone migration is not lithologically controlled. Implications of these important assumptions have been investigated. Our results suggest that the Arabian Peninsula underwent two phases of asymmetric uplift during the last 20-30 Ma at rates of 0.05-0.1 mm a-1. The southwestern flank of the peninsula has been uplifted by 1.5-2.5 km. Regional stratigraphic constraints, the age and composition of volcanism, paleosol formation, incised peneplains, emergent marine terraces, and thermochronometric measurements corroborate our calculated patterns of uplift. Progressive development of three domal swells along the western margin of the peninsula is consistent with localized upwelling of hot asthenospheric mantle.

  17. Weather types, precipitation and soil erosion in the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Nadal Romero, Estela; Cortesi, Nicola; Lucia, Ana; Pacheco, Edinson; Taguas, Encarnación; Francisco Martínez-Murillo, Juan; Romero Díaz, Asunción; Gómez, José Alfonso; Úbeda, Xavi; Damián Ruiz-Sinoga, José; Lasanta, Teodoro; González-Hidalgo, Carlos

    2014-05-01

    For a long time, precipitation has been recognized as one of the main factors driving soil erosion and sediment yield. In climatology, one of the most common approaches in analyzing precipitation is the circulation of weather types (WTs), which categorize the continuum of atmospheric circulation into a small number of classes or types. In the Iberian Peninsula (IP), previous researches have demonstrated the usefulness of the WT approach in determining the behavior of rainfall, and its spatial and temporal distribution. These studies have shown that specific weather types are the main driven factors of precipitation distribution accordingly different areas, and shown that precipitations depends on more WTs to the west than to the east of the IP. In this study, we present an analysis of weather types and sediment yield data from different study areas in the Iberian Peninsula. To do that we have collected and joint different research groups spread along the national Spanish land, and combine different databases with the WT classification calculated using the NMC/NCAR 40-Year Reanalysis Project. We discuss two main hypotheses: (i) there exist some links between weather types and soil erosion in the Iberian Peninsula, and then (ii) spatial patterns of sediment yield and erosion would be emerged in the Iberian Peninsula accordingly the spatial distribution of the relationship between WTs and sedimentary processes. This pioneer research, with different areas across the Iberian Peninsula will be a valuable tool in understanding the relationships between weather types, precipitation and soil erosion dynamics.

  18. Chemical constraints of groundwater management in the Yucatan peninsula, Mexico

    NASA Astrophysics Data System (ADS)

    Back, W.; Lesser, J. M.

    1981-05-01

    Two critical objectives of water management in the Yucatan are: (1) to develop regional groundwater supplies for an expanding population and tourism based on the Mayan archeological sites and excellent beaches; and (2) to control groundwater pollution in a chemically sensitive system made vulnerable by geologic conditions. The Yucatan peninsula is a coastal plain underlain by permeable limestone and has an annual rainfall of more than 1000 mm. Such a setting should provide abundant supplies of water; however, factors of climate and hydrogeology have combined to form a hydrologic system with chemical boundaries that decrease the amount of available fresh water. Management of water resources has long had a major influence on the cultural and economic development of the Yucatan. The Mayan culture of the northern Yucatan developed by extensive use of groundwater. The religion was water-oriented and the Mayan priests prayed to Chac, the water god, for assistance in water management primarily to decrease the severity of droughts. The Spaniards arrived in 1517 and augmented the supplies by digging wells, which remained the common practice for more than 300 years. Many wells now have been abandoned because of serious problems of pollution resulting from the use of a sewage disposal well adjacent to each supply well. The modern phase of water management began in 1959 when the Secretaría de Recursos Hidráulicos (S.R.H.) was charged with the responsibility for both scientific investigations and development programmes for water-supply and sewage-disposal systems for cities, villages and islands.

  19. Rayleigh wave ellipticity across the Iberian Peninsula and Morocco

    NASA Astrophysics Data System (ADS)

    Gómez García, Clara; Villaseñor, Antonio

    2015-04-01

    Spectral amplitude ratios between horizontal and vertical components (H/V ratios) from seismic records are useful to evaluate site effects, predict ground motion and invert for S velocity in the top several hundred meters. These spectral ratios can be obtained from both ambient noise and earthquakes. H/V ratios from ambient noise depend on the content and predominant wave types: body waves, Rayleigh waves, a mixture of different waves, etc. The H/V ratio computed in this way is assumed to measure Rayleigh wave ellipticity since ambient vibrations are dominated by Rayleigh waves. H/V ratios from earthquakes are able to determine the local crustal structure at the vicinity of the recording station. These ratios obtained from earthquakes are based on surface wave ellipticity measurements. Although long period (>20 seconds) Rayleigh H/V ratio is not currently used because of large scatter has been reported and uncertainly about whether these measurements are compatible with traditional phase and group velocity measurements, we will investigate whether it is possible to obtain stable estimates after collecting statistics for many earthquakes. We will use teleseismic events from shallow earthquakes (depth ≤ 40 km) between 2007 January 1 and 2012 December 31 with M ≥ 6 and we will compute H/V ratios for more than 400 stations from several seismic networks across the Iberian Peninsula and Morocco for periods between 20 and 100 seconds. Also H/V ratios from cross-correlations of ambient noise in different components for each station pair will be computed. Shorter period H/V ratio measurements based on ambient noise cross-correlations are strongly sensitive to near-surface structure, rather than longer period earthquake Rayleigh waves. The combination of ellipticity measurements based on earthquakes and ambient noise will allow us to perform a joint inversion with Rayleigh wave phase velocity. Upper crustal structure is better constrained by the joint inversion compared

  20. Chemical constraints of groundwater management in the Yucatan peninsula, Mexico

    USGS Publications Warehouse

    Back, W.; Lesser, J.M.

    1981-01-01

    Two critical objectives of water management in the Yucatan are: (1) to develop regional groundwater supplies for an expanding population and tourism based on the Mayan archeological sites and excellent beaches; and (2) to control groundwater pollution in a chemically sensitive system made vulnerable by geologic conditions. The Yucatan peninsula is a coastal plain underlain by permeable limestone and has an annual rainfall of more than 1000 mm. Such a setting should provide abundant supplies of water; however, factors of climate and hydrogeology have combined to form a hydrologic system with chemical boundaries that decrease the amount of available fresh water. Management of water resources has long had a major influence on the cultural and economic development of the Yucatan. The Mayan culture of the northern Yucatan developed by extensive use of groundwater. The religion was water-oriented and the Mayan priests prayed to Chac, the water god, for assistance in water management primarily to decrease the severity of droughts. The Spaniards arrived in 1517 and augmented the supplies by digging wells, which remained the common practice for more than 300 years. Many wells now have been abandoned because of serious problems of pollution resulting from the use of a sewage disposal well adjacent to each supply well. The modern phase of water management began in 1959 when the Secretari??a de Recursos Hidra??ulicos (S.R.H.) was charged with the responsibility for both scientific investigations and development programmes for water-supply and sewage-disposal systems for cities, villages and islands. ?? 1981.

  1. Volcanic Facies of the Lower Jurassic Talkeetna Formation, Iniskin Peninsula to Tuxedni Bay, Alaska Peninsula

    NASA Astrophysics Data System (ADS)

    Bull, K. F.

    2015-12-01

    The Lower Jurassic Talkeetna Formation (Jtk), a >1,000-km-long belt of vol­canic facies within the accreted intra-oceanic Talkeetna Arc has been characterized within the Talkeetna Mountains, but on the Alaska Peninsula Jtk facies have not previously been described in detail. Here we describe facies of the Jtk stretching from the Iniskin Peninsula to Tuxedni Bay. On the Iniskin Peninsula, a high concentration and great thickness of mafic to intermediate lavas, associated autobreccias and hyaloclastites, fluidal-clast breccias and possible pillows are suggestive of one or more submarine effusive eruption centers. Also volumetrically significant are non-stratified polymictic volcaniclastic breccia facies. Minor facies include thinly bedded volcaniclastic sandstone to pebble breccia-conglomerate facies, some of which are shard- and pumice-bearing pyroclastic deposits preserved in thinly bedded deposits, indicative of episodes of explosive volcanism and the eruption-fed nature of some of the deposits. North of Chinitna Bay, coherent facies tend to be thin and relatively small in volume. Volcaniclastic facies provide evidence of subaerial-fluvial deposition, and pyroclastic activity. Thinly bedded, laterally continuous beds locally exhibit cross-laminations, channel fills, normal grading and lenticular beds, and contain plant fossils. Within this sequence is a 10-m-thick pumice breccia containing fossilized logs, underlain by a thin, weakly laminated, pumice- and lithic-bearing volcaniclastic siltstone to sandstone. The log-bearing pumice breccia and the lithic-bearing laminated basal unit represent pyroclastic density current (PDC) facies deposited in a subaerial or possibly shallow aqueous environment. Underlying the PDC deposit are several 30-cm-thick maroon and olive green volcaniclastic fine-grained sandstone and siltstone beds containing channel fills, cross-beds and lenticular beds. Marbles exposed in the contact zone between the intrusions of Alaska

  2. Alaska peninsula stable isotope and radioisotope chemistry: a study in temporal and adaptive diversity.

    PubMed

    Coltrain, Joan Brenner

    2010-12-01

    Purified bone collagen from a small suite of human remains recovered at three sites on the Alaska Peninsula (Port Moller, Brooks River, and Mink Island) were analyzed for stable carbon and nitrogen isotope chemistry and were accelerator radiocarbon dated. Because samples sizes were small and faunal isotope chemistry lacking, results should be considered preliminary. However, these data indicate that each locality was represented by a somewhat different suite of subsistence strategies and covered a distinct temporal span. Port Moller burials (n = 7) from the Hot Springs site date to a calibrated 2σ range of 3547-1388 BP. Although marine foods clearly made the greatest contribution to these diets, individuals were not as heavily reliant on high-trophic-level marine taxa as eastern Aleutian groups to the west, given their intake of salmon and evidence of caribou hunting. Brooks River burials (n = 9) expressed an inland foraging focus with significant reliance on caribou and spawning salmon and covered a calibrated 2σ range of 1484-381 BP. In contrast, individuals from Mink Island (n = 7), dating to cal. 666-292 BP, were heavily reliant on high-trophic-level marine prey similar to but not as enriched isotopically as the Aleut, perhaps a consequence of limited access to caribou and greater reliance on invertebrates. This pattern suggests that prehistoric economic strategies on the Alaska Peninsula were diverse, characterized by fine-tuned adaptations to local ecological settings, perhaps mediated by ethnic factors and territorial and social pressures. PMID:21417886

  3. Rhizobium anhuiense as the predominant microsymbionts of Lathyrus maritimus along the Shandong Peninsula seashore line.

    PubMed

    Li, Yan; Wang, En Tao; Liu, Yajing; Li, Xiangyue; Yu, Bing; Ren, Chenggang; Liu, Wei; Li, Yunzhao; Xie, Zhihong

    2016-09-01

    Beach pea [Lathyrus maritimus Bigelow, or Lathyrus japonicus subsp. maritimus (L.) P.W. Ball] is a wild legume distributed on the seashore line, and the rhizobia nodulating with this plant have been reported only rarely. In order to reveal the diversity of beach pea rhizobia on the seashore line of Shandong Peninsula, China, a total of 124 bacterial strains were isolated from the root nodules of beach pea plants collected from five sites. All the isolates were divided into five recA types after screening by recA gene sequence analysis and they consisted of Rhizobium anhuiense covering 122 symbiotic isolates in three recA types, as well as two single isolates Rhizobium sp. and Rhizobium lusitanum representing distinct recA types. The recA genotype III of R. anhuiense (103 isolates) represented by strain YIC11270 was dominant at all five sampling sites. Identical symbiotic genes (nodC and nifH) were detected in the three recA genotypes of R. anhuiense isolates that were closely related to those of the pea and faba rhizobia. This study clarified that R. anhuiense was the main symbiont for beach pea rhizobia on the seashore line of Shandong Peninsula. The low level genetic diversity of beach pea rhizobia revealed by both MLSA and the symbiotic genes might be related to the strong selection pressure produced by the saline-alkaline environment and the host plants. PMID:27480059

  4. Composition and microstructure of Roman metallic artefacts of Southwestern Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Valério, P.; Voráčová, E.; Silva, R. J. C.; Araújo, M. F.; Soares, A. M. M.; Arruda, A. M.; Pereira, C.

    2015-10-01

    The Roman invasion introduces new alloys and metallurgical practices in Iberian Peninsula. The southwestern end of this region has many evidences of connections with the Roman World, but there are no studies about the manufacture and use of copper-based artefacts during this period. Therefore, a set of about 20 ornaments, tools and small attachments recovered at the Roman sites of Monte Molião and Cidade das Rosas was studied by an analytical approach combining micro-EDXRF, optical microscopy, SEM-EDS and Vickers microhardness testing. The artefact composition shows a good correlation with function, namely pure copper for nails and rivets, low-tin bronze (2-6 wt% Sn) for basic tools, high-tin bronze (14 wt% Sn) for fibulae and high-lead bronze (19 wt% Pb) for a decorated jug handle. The manufacture also depends on function because most artefacts were subjected to thermomechanical processing, except the ornaments that would not benefit from post-casting work. Brass and gunmetal were only present in the site with a later chronology. A metallurgy visibly ruled by economical, aesthetical and technological concerns reinforces the evidences about the total integration of Southwestern Iberian Peninsula in the Roman World, but further studies will be essential to determine the evolution of copper-based alloys in Lusitania under Roman influence.

  5. Phosphorus-31 nuclear magnetic resonance spectroscopy transect study of poultry operations on the Delmarva Peninsula.

    PubMed

    Hill, Jane E; Cade-Menun, Barbara J

    2009-01-01

    Nonpoint source phosphorus (P) pollution into the Chesapeake Bay watershed from poultry operations contributes to the algal blooms, hypoxia, anoxia, and fish kill events that occur there most years. A major source of soluble, bioavailable P species is poultry litter, which is used as a crop fertilizer on fields adjacent to the tributaries of the Bay. A potentially significant source of orthophosphate in the litter is the heavily phosphorylated compound myo-inositol hexakisphosphate (phytate), which is indigestible by poultry and thus becomes a major component of their excreta. Phytate evaluation in environmental samples is expensive; hence, its impact is not captured in standard farmer-friendly eutrophication potential guides, like Delaware's Phosphorus Site Index. In this transect study of two poultry operations on the Delmarva Peninsula, we measured the incidence of all P compounds using solution 31P nuclear magnetic resonance (NMR) spectroscopy and extracts, relating them to relevant geochemical properties. The contribution of phytate to the overall pool of P declined from around 50% in manures to between 2 and 13% in down-gradient soils and sediments, corresponding to a rise in the relative proportion of orthophosphate (increasing from 39% to 65-88%). The results show that the large pool of phytate P spread onto croplands during standard operating practice at poultry farms on the Delmarva Peninsula does not appear to accumulate; rather, phytate decreases in down-gradient locations, most likely due to transport off-site and/or through in situ biological activity. PMID:19141802

  6. Groundwater temperature transients on the Armutlu peninsula, eastern Marmara region

    NASA Astrophysics Data System (ADS)

    Woith, Heiko; Caka, Deniz; Seyis, Cemil; Italiano, Francesco; Celik, Cengiz; Wang, Rongjiang; Baris, Serif

    2016-04-01

    Since many years MAM and GFZ in co-operation with Kocaeli University (KU) operate fluid monitoring stations around the Sea of Marmara. In the frame of MARsite (MARsite has received funding from the European Union's Seventh Programme for research, technological development and demonstration under grant agreement No 308417) these networks were jointly evaluated for the first time. The on-land fluid monitoring networks continuously monitor the following parameters: soil radon (21 sites), temperature and conductivity of thermal springs (9 sites) operated by MAM covering the whole Marmara region; fluid pressure and water level/temperature (8 sites) within ARNET operated by GFZ/KU. ARNET is a combined seismological/hydrogeological monitoring network covering the Armutlu peninsula located SE of Istanbul. Additional to the geothermal wells and springs - our main target to detect transients of potentially seismo-tectonic origin - three shallow groundwater wells (tenth of meters deep) are being operated to identify and quantify seasonal variations, and meteorological influences like rainfall and snowmelt. But it turned out that these shallow aquifer systems showed very stable conditions with very small annual temperature amplitudes (0.2 - 0.3°C). One of these shallow monitoring wells is located just south of Lake Iznik (in the village of Sölöz) very close to the southern branch of the North Anatolian Fault Zone. Water level showed a steady decreasing trend since June 2012. This trend resulted in a data gap starting in January 2014, when the water level dropped below the sensor position. After adjusting the sensor position, positive spikes in the borehole temperature were recorded in June and August 2014, and again in 2015. The spikes are characterised by a sharp temperature increase followed by a decay lasting several days until the pre-event temperature was reached again. Since the spikes occurred on two independent logger systems, and since they lasted several days, a

  7. Paleomagnetism of Silver Island, Keweenaw Peninsula, Michigan: Additional Support (?) for the Primary Curvature of the MCR

    NASA Astrophysics Data System (ADS)

    Diehl, J. F.; Durant, A. J.; Schepke, C.

    2009-05-01

    Silver Island lies between Eagle Harbor and Copper Harbor on the NW coastline of the Keweenaw Peninsula, Michigan. The island consists of a series of basaltic lava flows which dip to the north-northwest (356°) at an angle of approximately 38°. These flows constitute part of the Lake Shore Traps (LST), a series of interbedded lava flows within the Copper Harbor Conglomerate (CHC). The LST represent the youngest eruptive material associated with the 1.1 Ga Mid-Continent Rift (MCR). The most recent paleomagnetic study (now 15 years old) on the Lakeshore Traps (LST) defined three distinct directional clusters. Each cluster of directions corresponded to a different stratigraphic package of the LST within the CHC and all have extremely low between-site dispersion (s ˜ 4°) suggesting rather rapid emplacement of the LST packages. Consequently, each cluster has its own unique direction of magnetization. Since the lower two LST packages crop out along the coast line of the Peninsula with different structural trends, an opportunity was presented to test the conclusions of Hnat et al. (2006) that the curvature of the MCR was primary. To that end nine lava flows were sampled on Silver Island and their mean direction compared to the equivalent mean from lava flows sampled by Diehl and Haig (1994) from the tip of the Keweenaw Peninsula (upper lava flows of the Middle LST) which have an entirely different structural trend. Characteristic directions of magnetization of the Silver Island lava flows were isolated either using alternating field, thermal or a combination of both. The mean direction of magnetization for the nine sites is: D = 277.7°, I = 46.9°, α95 = 3.0°, k = 292.5. The mean direction recalculated from the Diehl and Haig study is: D = 277.8°, I = 40.6°, α95 = 2.9°, k = 315.7. Although the declinations of the two means are identical, interestingly the two means are statistically distinct at the 95% confidence level. Fold tests were inconclusive. Nevertheless

  8. Surface Ozone Dynamics in the Kola Peninsula Region

    NASA Astrophysics Data System (ADS)

    Beloglazov, M. I.; Karpechko, A. Yu.; Nikulin, G. N.; Roumjantsev, S. A.

    Measurements of surface ozone from the centre of the Murmansk Region (Apatity, Kola peninsula) and its southern part (Kovda, White Sea coast) give a picture of the behaviour of this air component on the Kola peninsula and surrounding vicinity. Simultaneous measurements in Apatity and Kovda have shown that the ozone concentration in Apatity is roughly twice as much as in Kovda. This fact may be explained by the local wind circulation and the presence of bromine near the coast of the Kola Peninsula. An inverse correlation is found between the ozone and nitrogen oxide concentrations from observations near motorways in Apatity. A decrease of nitrogen oxide concentration accompanies the growth of ozone on average. Thus, Apatity is a northern city in which the air pollution by traffic emissions decreases the ozone content.

  9. Tectonic, Climatic, and Cryospheric Evolution of the Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2013-06-01

    For millennia, Antarctica has been a frozen continent, a land of ice and snow where complex life persists rather than thrives. But Antarctica has not always been this way. Millions of years ago the southern continent was teeming with life. Changing oceans and a plummeting atmospheric carbon dioxide concentration drove a dramatic evolution of the Antarctic continent. To provide a record of these ancient climatic shifts, the 2005-2006 SHALDRIL drilling program collected sediment cores from the bed of the iceberg-filled seas off the Antarctic Peninsula. In the AGU book Tectonic, Climatic, and Cryospheric Evolution of the Antarctic Peninsula, editors John B. Anderson and Julia S. Wellner draw on the findings garnered from SHALDRIL to explore the changing Antarctic Peninsula. In this interview, Eos talks to John B. Anderson.

  10. Paleomagnetism of early Tertiary Alaska Peninsula rocks and implications for docking of peninsular terrane

    SciTech Connect

    Whitney, J.W.; Levinson, R.A.; Van Alstine, D.R.

    1985-04-01

    In order to refine the tectonic history of the peninsular terrane, Alaska, 22 sites (averaging 10 samples/site) in Paleogene Tertiary volcanic and sedimentary formations were sampled in the vicinity of Chignik, on the Pacific side of the Alaska Peninsula. Ten of the sites were drilled in the early Oligocene Meshik volcanics, ranging from andesite to basalt, and the other twelve sites were drilled in the late Eocene Tolstoi Formation sediments. Nine of the volcanic sites yielded stable R and/or N characteristic magnetization. Virtually no fine-grained, interbedded sediments occur with the Meshik volcanics at the sample sites, thus making reliable paleohorizontal determinations difficult. Although flow attitudes were tentatively used, it became rapidly apparent that problems of initial dip were insurmountable. As a result, all volcanic sites were considered unreliable for determining a meaningful paleomagnetic inclination. Upon thermal demagnetization, five of the sedimentary sites were judged stable. The mode of the paleomagnetic direction was calculated, D/I = 349.8/75.3(..beta..95 = 8.5), indicating no significant rotation. Uncertainties in structural corrections, however, may render only the inclination meaningful, which, from McFadden statistics yields, I = 75.9, ..cap alpha..95 = 7.9, corresponding to a paleolatitude of 63.3/sup 0/. This paleolatitude agrees with the expected value for the North American craton at 40 m.y. B.P., implying that the peninsular terrane had docked at at least that time.

  11. Anaglyph with Landsat Overlay, Kamchatka Peninsula, Russia

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This 3-D anaglyph shows an area on the western side of the volcanically active Kamchatka Peninsula, Russia. Red-blue glasses are required to see the 3-D effect. The topographic data are from the first C-band mapping swath of the Shuttle Radar Topography Mission (SRTM). Images from the optical Landsat satellite are overlain on the SRTM topography data. The meandering channel of the Tigil River is seen along the bottom of the image, at the base of steep cliffs. In the middle left of the image, a terrace indicates recent uplift of the terrain and downcutting by the river. High resolution SRTM topographic data will be used by geologists and hydrologists to study the interplay of tectonic uplift and erosion.

    This anaglyph was generated using topographic data from the Shuttle Radar Topography Mission to create two differing perspectives of a single image, one perspective for each eye. Each point in the image is shifted slightly, depending on its elevation. When viewed through special glasses, the result is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter. The United States Geological Survey's Earth Resources Observations Systems (EROS) Data Center, Sioux Falls, South Dakota, provided the Landsat data, which are overlain on the topography.

    The Shuttle Radar Topography Mission (SRTM), launched on February 11,2000, uses the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. The mission is designed to collect three-dimensional measurements of the Earth's surface. To collect the 3-D data, engineers added a 60-meter-long (200-foot) mast, an additional C-band imaging antenna and improved tracking and navigation devices. The mission is a cooperative project between the National Aeronautics and Space Administration (NASA

  12. Interactions Between Islamic and Christian Traditions in the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    González-García, A. César; Belmonte, Juan Antonio

    Pre-Romanesque churches in the Iberian Peninsula include a number of constructions from the fourth-fifth to the eleventh century when the first Romanesque churches appeared in the north of Spain. This period of time coincided with the Muslim invasion of the Peninsula. An important number of churches and mosques were built with prescriptions for the orientation, which possibly included astronomical observations. Investigations show that both groups of monuments reacted by avoiding the areas of theoretical influence of the other religion while trying to obey their own orientation rules.

  13. Water Quality in the Delmarva Peninsula, Delaware, Maryland, and Virginia, 1999-2001

    USGS Publications Warehouse

    Denver, Judith M.; Ator, Scott W.; Debrewer, Linda M.; Ferrari, Matthew J.; Barbaro, Jeffrey R.; Hancock, Tracy C.; Brayton, Michael J.; Nardi, Mark R.

    2004-01-01

    This report contains the major findings of a 1999-2001 assessment of water quality in the Delmarva Peninsula. It is one of a series of reports by the National Water-Quality Assessment (NAWQA) Program that present major findings in 51 major river basins and aquifer systems across the Nation. In these reports, water quality is assessed at many scales?from local ground-water flow paths to regional ground-water networks and in surface water?and is discussed in terms of local, State, and regional issues. Conditions in the Delmarva Peninsula are compared to conditions found elsewhere and to selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. This report is intended for individuals working with water-resource issues in Federal, State, or local agencies; universities; public interest groups; or in the private sector. The information will be useful in addressing a number of current issues, such as the effects of agricultural and urban land use on water quality, human health, drinking water, source-water protection, hypoxia and excessive growth of algae and plants, pesticide registration, and monitoring and sampling strategies. This report is also for individuals who wish to know more about the quality of streams and ground water in areas near where they live, and how that water quality compares to the quality of water in other areas across the Nation. Other products describing water-quality conditions in the Delmarva Peninsula are available. Detailed technical information, data and analyses, methodology, models, graphs, and maps that support the findings presented in this report can be accessed from http://md.water.usgs.gov/delmarva. Other reports in this series and data collected from other basins can be accessed from the national NAWQA Web site (http://water.usgs.gov/nawqa).

  14. Geology and timing of mineralization at the Cangshang gold deposit, north-western Jiaodong Peninsula, China

    USGS Publications Warehouse

    Zhang, X.; Cawood, Peter A.; Wilde, S.A.; Liu, R.; Song, H.; Li, W.; Snee, L.W.

    2003-01-01

    The Cangshang gold deposit of the northwestern Jiaodong Peninsula contains reserves of greater than 50 tonnes (t) and is developed by the largest open pit gold mine in China. This deposit is a Jiaojia-style (i.e. disseminated-and-veinlet) deposit. It is controlled by the San-Cang fault zone, which trends ???040?? and dips 40-75??SE at the mine site. The main (no. 1) orebody lies between a hanging wall of Precambrian metamorphic rocks (mainly amphibolite) of the Fenzishan Group and a footwall composed of the Mesozoic Linglong granitoid. The ore zone is mainly composed of pyritized, sericitized and silicified granitoid, which has undergone variable degrees of cataclasis. SHRIMP U-Pb dating of zircon indicates that the protolith of the hanging wall amphibolite was formed at 2530 ?? 17 Ma and underwent metamorphism at 1852 ?? 37 Ma. The footwall granodiorite has been dated at 166 ?? 4 Ma, whereas zircons from the ore zone yield a younger age of 154 ?? 5 Ma. Cathodoluminescence images of zircons from the granodiorite and ore zone show oscillatory zonation indicative of an igneous origin for both and the ages of these zircons, therefore, are all interpreted to be representative of magmatic crystallization. Dating of sericite by 40Ar-39Ar has been used to directly determine the timing of formation of the Cangshang deposit, providing the first time absolute age on formation of the Jiaojia-style gold deposits. The well-defined age of 121.3 ?? 0.2 Ma provides the precise timing of gold mineralization at the Cangshang deposit. This age is consistent with those of Linglong-style (vein type) gold mineralization, also from the north-western Jiaodong Peninsula, at between 126 and 120 Ma. Therefore, our work indicates that both styles of gold deposits in the Jiaodong Peninsula were formed during the same mineralization event.

  15. Paleoclimate and Paleoenvironmental Reconstructions on the North Kola Peninsula during the Past 2000 Years According Pollen Data

    NASA Astrophysics Data System (ADS)

    Nosevich, Ekaterina; Sapelko, Tatjana; Anisimov, Mikhail

    2014-05-01

    Pollen data and radiocarbon data have enabled to reconstruct the periods of vegetation that depended on the climate changes. Records from different types of deposits allow to receive more information and to make paleoclimate reconstructions. Lake and bog sediments are the best sources for palaeoreconstruction. Palaeoclimatic changes, tectonic and coastline movement during Late Holocene caused vegetation changes on the North Kola Peninsula. Our data from pollen records from different sites on the north coast of the Kola Peninsula covers the Late Holocene about last 2000 years. We studied different types of sediment cores in the area between 69° N and 70° N, 31°12' E and 35° E. We have studied peat deposits, small lake sediments and archaeological site on the Bolshoy Oleniy Island in Kola fjord, Barents Sea, and peat bog deposits in the Teriberka area. All the cores are studied by different methods where the core was pollen analysis. It has allowed tracking the periods of vegetation history in the tundra zone. Pollen reconstructions are confirmed by radiocarbon data. Our data was compared with other researches and we made correlations between pollen records from different lake deposits. Modern vegetation presents south tundra type of associations. Teriberka area is unique: almost existing types of tundra landscapes are presented here in small territory, including "typical tundra" with subshrubs formations. For paleoclimate reconstructions we have studied surface samples by pollen analysis. Samples were collected in 3 regions of Kola Peninsula. Samples have been taken on the Sredniy and Rybachiy Peninsulas (Murman region) in the south tundra with rich associations and boreal species of herbs. In the Olenegorsk region we selected vegetation associations not damaged by human and we collected surface samples on the border of forest tundra and northern taiga. In Apatity region we studied pollen records in North taiga landscapes. This data characterize regional and

  16. 46 CFR 7.165 - Kenai Peninsula, AK to Kodiak Island, AK.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Kenai Peninsula, AK to Kodiak Island, AK. 7.165 Section... BOUNDARY LINES Alaska § 7.165 Kenai Peninsula, AK to Kodiak Island, AK. (a) A line drawn from the southernmost extremity of Kenai Peninsula at longitude 151°44.0′ W. to East Amatuli Island Light; thence to...

  17. 46 CFR 7.165 - Kenai Peninsula, AK to Kodiak Island, AK.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Kenai Peninsula, AK to Kodiak Island, AK. 7.165 Section... BOUNDARY LINES Alaska § 7.165 Kenai Peninsula, AK to Kodiak Island, AK. (a) A line drawn from the southernmost extremity of Kenai Peninsula at longitude 151°44.0′ W. to East Amatuli Island Light; thence to...

  18. 46 CFR 7.165 - Kenai Peninsula, AK to Kodiak Island, AK.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Kenai Peninsula, AK to Kodiak Island, AK. 7.165 Section... BOUNDARY LINES Alaska § 7.165 Kenai Peninsula, AK to Kodiak Island, AK. (a) A line drawn from the southernmost extremity of Kenai Peninsula at longitude 151°44.0′ W. to East Amatuli Island Light; thence to...

  19. 46 CFR 7.165 - Kenai Peninsula, AK to Kodiak Island, AK.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Kenai Peninsula, AK to Kodiak Island, AK. 7.165 Section... BOUNDARY LINES Alaska § 7.165 Kenai Peninsula, AK to Kodiak Island, AK. (a) A line drawn from the southernmost extremity of Kenai Peninsula at longitude 151°44.0′ W. to East Amatuli Island Light; thence to...

  20. 46 CFR 7.165 - Kenai Peninsula, AK to Kodiak Island, AK.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Kenai Peninsula, AK to Kodiak Island, AK. 7.165 Section... BOUNDARY LINES Alaska § 7.165 Kenai Peninsula, AK to Kodiak Island, AK. (a) A line drawn from the southernmost extremity of Kenai Peninsula at longitude 151°44.0′ W. to East Amatuli Island Light; thence to...

  1. Trends of Rural Tropospheric Ozone at the Northwest of the Iberian Peninsula

    PubMed Central

    Saavedra, S.; Rodríguez, A.; Souto, J. A.; Casares, J. J.; Bermúdez, J. L.; Soto, B.

    2012-01-01

    Tropospheric ozone levels around urban and suburban areas at Europe and North America had increased during 80's–90's, until the application of NOx reduction strategies. However, as it was expected, this ozone depletion was not proportional to the emissions reduction. On the other hand, rural ozone levels show different trends, with peaks reduction and average increments; this different evolution could be explained by either emission changes or climate variability in a region. In this work, trends of tropospheric ozone episodes at rural sites in the northwest of the Iberian Peninsula were analyzed and compared to others observed in different regions of the Atlantic European coast. Special interest was focused on the air quality sites characterization, in order to guarantee their rural character in terms of air quality. Both episodic local meteorological and air quality measurements along five years were considered, in order to study possible meteorological influences in ozone levels, different to other European Atlantic regions. PMID:22649298

  2. Probabilistic seismic hazard analysis for Sumatra, Indonesia and across the Southern Malaysian Peninsula

    USGS Publications Warehouse

    Petersen, M.D.; Dewey, J.; Hartzell, S.; Mueller, C.; Harmsen, S.; Frankel, A.D.; Rukstales, K.

    2004-01-01

    The ground motion hazard for Sumatra and the Malaysian peninsula is calculated in a probabilistic framework, using procedures developed for the US National Seismic Hazard Maps. We constructed regional earthquake source models and used standard published and modified attenuation equations to calculate peak ground acceleration at 2% and 10% probability of exceedance in 50 years for rock site conditions. We developed or modified earthquake catalogs and declustered these catalogs to include only independent earthquakes. The resulting catalogs were used to define four source zones that characterize earthquakes in four tectonic environments: subduction zone interface earthquakes, subduction zone deep intraslab earthquakes, strike-slip transform earthquakes, and intraplate earthquakes. The recurrence rates and sizes of historical earthquakes on known faults and across zones were also determined from this modified catalog. In addition to the source zones, our seismic source model considers two major faults that are known historically to generate large earthquakes: the Sumatran subduction zone and the Sumatran transform fault. Several published studies were used to describe earthquakes along these faults during historical and pre-historical time, as well as to identify segmentation models of faults. Peak horizontal ground accelerations were calculated using ground motion prediction relations that were developed from seismic data obtained from the crustal interplate environment, crustal intraplate environment, along the subduction zone interface, and from deep intraslab earthquakes. Most of these relations, however, have not been developed for large distances that are needed for calculating the hazard across the Malaysian peninsula, and none were developed for earthquake ground motions generated in an interplate tectonic environment that are propagated into an intraplate tectonic environment. For the interplate and intraplate crustal earthquakes, we have applied ground

  3. Phosphorus leaching from agricultural soils of the Delmarva Peninsula, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leaching of phosphorus (P) mobilizes edaphic and applied sources of P and is a primary pathway of concern in agricultural soils of the Delmarva Peninsula, which defines the eastern boundary of the eutrophic Chesapeake Bay. We evaluated P leaching before and after poultry litter application from inta...

  4. 46. Photocopy of photograph (Pentran file), (from Alexander Brown's Peninsula's ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. Photocopy of photograph (Pentran file), (from Alexander Brown's Peninsula's Last Street Cars, Daily Press, January 15, 1956) photographer unknown. The first streetcar (with dignitaries) to make the run from Newport News to a new housing development named Hilton Village in September 1918. - Newport News & Old Point Railway & Electric Company, Trolley Barn & Administration Building, 3400 Victoria Boulevard, Hampton, Hampton, VA

  5. 48. Photocopy of photograph (from Reflections, Peninsula Transportation District Commission, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    48. Photocopy of photograph (from Reflections, Peninsula Transportation District Commission, 1985. Original three CRT buses in 1928. *FOR Photocopy of photograph (from the Charles H. Taylor Memorial Library), photographer unknown. Trolley car No. 315 shown April 25, 1929 at the Trolley Barn. SEE FIELD NOTES - Newport News & Old Point Railway & Electric Company, Trolley Barn & Administration Building, 3400 Victoria Boulevard, Hampton, Hampton, VA

  6. A Sketch of Language History in the Korean Peninsula

    PubMed Central

    Lee, Sean

    2015-01-01

    Among 7100 languages spoken on Earth, the Koreanic language is the 13th largest, with about 77 million speakers in and around the Korean Peninsula. In comparison to other languages of similar size, however, surprisingly little is known about the evolution of the Koreanic language. This is mainly due to two reasons. The first reason is that the genealogical relationship of the Koreanic to other neighboring languages remains uncertain, and thus inference from the linguistic comparative method provides only provisional evidence. The second reason is that, as the ancestral Koreanic speakers lacked their own writing system until around 500 years ago, there are scant historical materials to peer into the past, except for those preserved in Sinitic characters that we have no straightforward way of interpreting. Here I attempt to overcome these disadvantages and shed some light on the linguistic history of the Korean Peninsula, by analyzing the internal variation of the Koreanic language with methods adopted from evolutionary biology. The preliminary results presented here suggest that the evolutionary history of the Koreanic language is characterized by a weak hierarchical structure, and intensive gene/culture flows within the Korean Peninsula seem to have promoted linguistic homogeneity among the Koreanic variants. Despite the gene/culture flows, however, there are still three detectable linguistic barriers in the Korean Peninsula that appear to have been shaped by geographical features such as mountains, elevated areas, and ocean. I discuss these findings in an inclusive manner to lay the groundwork for future studies. PMID:26024377

  7. 77 FR 65359 - Olympic Peninsula Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ... Forest Service Olympic Peninsula Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION... Resource Advisory Committee (RAC). The RAC will be responsible for reviewing and recommending land... the act be reauthorized this year. RAC members represent a wide range of interests. The...

  8. Blueberry Trials on Alaska's Kenai Peninsula: First Year Report

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In June 2009, 9 plants each of three highbush and six half-high blueberry cultivars were planted at test plots on two commercial farms on Alaska's Kenai Peninsula. The purpose of the trials was to determine if domestic blueberry plants could survive and produce crops in Southcentral Alaska. In Octob...

  9. 77 FR 53168 - Olympic Peninsula Resource Advisory Committee

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ... of meeting. SUMMARY: The Olympic Peninsula Resource Advisory Committee will meet in Olympia, WA. The... Black Lake Blvd. SW., Olympia, WA 98512. A conference call line will be made available for members of... Forest, Supervisor's Office, located in Olympia, WA. Please call ahead to Grace Haight at 360-956-2303...

  10. Pumas and Prepositions: Training Nature Guides in the Yucatan Peninsula.

    ERIC Educational Resources Information Center

    Brown, Cynthia

    2000-01-01

    In the Yucatan Peninsula (Mexico), the 10-week Nature Guide Training Program integrates English immersion with natural history and environmental interpretation to train rural adults as nature guides and conservation leaders. Most graduates have found work as ecotourism guides or in conservation-related activities, and many have provided English…

  11. Hemorrhagic pulmonary leptospirosis: three cases from the Yucatan peninsula, Mexico.

    PubMed

    Zavala-Velázquez, Jorge; Cárdenas-Marrufo, María; Vado-Solís, Ignacio; Cetina-Cámara, Marco; Cano-Tur, José; Laviada-Molina, Hugo

    2008-01-01

    Three leptospirosis cases with lung involvement are reported from the Yucatan Peninsula, Mexico. All three patients were admitted to the intensive care unit due to acute respiratory failure. Treatment with antibiotics resulted in favorable evolution despite the negative prognosis. Leptospirosis should be included in the differential diagnosis of patients with fever and lung involvement. PMID:18853016

  12. Recent Rapid Regional Climate Warming on the Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Vaughan, D. G.; Marshall, G. J.; Connolley, W. M.; Parkinson, C.; Mulvaney, R.; Hodgson, D. A.; King, J. C.; Pudsey, C. J.; Turner, J.

    2002-12-01

    The Intergovernmental Panel on Climate Change (IPCC) confirmed that global warming was 0.6 ñ 0.2 degrees C during the 20th Century and cited increases in greenhouse gases as a likely contributor. But this average conceals the complexity of observed climate change, which is seasonally biased, decadally variable and geographically patchy. In particular, over the last 50 years three high-latitude areas have undergone recent rapid regional (RRR) warming ? substantially more rapid than the global mean. We discuss the spatial and temporal significance of RRR warming in one area, the Antarctic Peninsula. New analyses of station records show no ubiquitous polar amplification of global warming but significant RRR warming on the Antarctic Peninsula. We investigate the likelihood that this could be amplification of a global warming, and use climate-proxy data to indicate that this RRR warming on the Antarctic Peninsula is unprecedented over the last two millennia and unlikely to be a natural mode of variability. We can show a strong connection between RRR warming and reduced sea-ice duration in an area on the west of the Antarctic Peninsula, but here we cannot yet distinguish cause and effect. Thus for the present we cannot determine which process causes the RRR warming, and until the mechanism initiating and sustaining it is understood, and is convincingly reproduced in climate models, we lack a sound basis for predicting climate change in this region over the coming century.

  13. Stable isotopes and Antarctic moss banks: Plants and soil microbes respond to recent warming on the Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Royles, Jessica; Amesbury, Matthew; Ogée, Jérôme; Wingate, Lisa; Convey, Peter; Hodgson, Dominic; Griffiths, Howard; Leng, Melanie; Charman, Dan

    2014-05-01

    The Antarctic Peninsula is one of the most rapidly warming regions on Earth, with air temperature increases of as much as 3°C recorded since the 1950s. However, the longer-term context of this change is limited and existing records, largely relying on ice core data, are not suitably located to be able to trace the spatial signature of change over time. We are working on a project exploiting stable isotope records preserved in moss peat banks spanning 10 degrees of latitude along the Antarctic Peninsula as an archive of late Holocene climate variability. Here we present a unique time series of past moss growth and soil microbial activity that has been produced from a 150 year old moss bank at Lazarev Bay, Alexander Island (69°S), a site at the southern limit of significant plant growth in the Antarctic Peninsula region. These moss banks are ideal archives for palaeoclimate research as they are well-preserved by freezing, generally monospecific, easily dated by radiocarbon techniques, and have sufficiently high accumulation rates to permit decadal resolution. We use accumulation rates, cellulose δ13C and fossil testate amoebae to show that growth rates, assimilation and microbial productivity rose rapidly in the 1960s, consistent with temperature change, although recently may have stalled, concurrent with other evidence. The increase in biological activity is unprecedented in the last 150 years. Along with work completed on Signy Island (60°S), in the South Orkney Islands, in which we used carbon isotope evidence to show recent climate-related enhancement of CO2 assimilation and peat accumulation rates in Antarctica, the observed relationships between moss growth, microbial activity and climate suggests that moss bank records have the potential to test the regional expression of temperature variability shown by instrumental data on the Antarctic Peninsula over centennial to millennial timescales, by providing long-term records of summer growth conditions

  14. Surface ozone levels in the forest and vegetation areas of the Biga Peninsula, Turkey.

    PubMed

    Sari, Deniz; İncecik, Selahattin; Ozkurt, Nesimi

    2016-11-15

    Spatial and temporal variability of surface ozone in the rural, mountainous and suburban sites of Biga Peninsula, at the northwest of Turkey which is about 300km southwest of Istanbul was investigated using passive samplers and continuous analyzers. A total 10 passive samplers and two continuous analyzers were used between 1.1.2013 and 31.12.2014. OX levels in the study region were examined to understand NOx dependent or independent contribution to ozone. The influences of the meteorological parameters on ozone levels were also examined by wind speed and ambient temperature. The results clearly show that mountainous areas have higher cumulative exposure to ozone than suburban locations. In order to understand the long range transport sources contributing to the high ozone levels in the region backward trajectories were computed using HYSPLIT model and then clustering of trajectories are performed. The results clearly show the characteristics of pollutant transport from north to Biga Peninsula. Additionally, AOT40 (Accumulated hourly O3 concentrations Over a Threshold of 40ppb) cumulative index was calculated using daytime hourly measurements. The results indicate that the ozone values in the study area are much higher than the critical levels for forest and vegetation based on EU Directive 2008/50/EC. PMID:27474990

  15. Structural setting and geochemistry of Devonian dikes in the Kola Peninsula

    NASA Astrophysics Data System (ADS)

    Terekhov, E. N.; Baluev, A. S.; Przhiyalgovsky, E. S.

    2012-01-01

    The structural setting and geochemistry of the Devonian dikes in the Kola Peninsula are considered. The alkaline dikes are controlled by rift- and drift-related structural elements. The first type of structures is exemplified by the Khibiny-Kontozero Fault Zone, which is regarded as a propagation zone of the East Barents Rift. The second type comprises Early Precambrian structural elements reactivated during Devonian drift of the East European Plate. Alkaline dikes occur in the ring structures at the ends of rifts and in the accommodation zones where the polarity of the main fault plane changes. These are the sites of accumulation and abrupt relaxation of tectonic stresses. Despite the significant differences in the petrography and chemistry of alkaline dikes, all of them are enriched in REE, apparently due to the elevated concentrations of these elements in the fluids. The dolerite dikes at the Murmansk Coast are located in the outer zone of the vast, concentrically zoned plateau basalt province with the East Barents Trough as its center. According to geophysical data, basaltic flows are suggested within this trough. The dolerite dikes increase in number in the inland propagation zone of the East Barents Trough extending in the Baltic Shield. The alkaline igneous rocks of the Kola Peninsula were formed under local compression at the periphery of the plateau basalt province.

  16. Emmons Lake Volcanic Center, Alaska Peninsula: Source of the Late Wisconsin Dawson tephra, Yukon Territory, Canada

    USGS Publications Warehouse

    Mangan, M.T.; Waythomas, C.F.; Miller, T.P.; Trusdell, F.A.

    2003-01-01

    The Emmons Lake Volcanic Center on the Alaska Peninsula of southwestern Alaska is the site of at least two rhyolitic caldera-forming eruptions (C1 and C2) of late Quaternary age that are possibly the largest of the numerous caldera-forming eruptions known in the Aleutian arc. The deposits produced by these eruptions are widespread (eruptive volumes of >50 km3 each), and their association with Quaternary glacial and eolian deposits on the Alaska Peninsula and elsewhere in Alaska and northwestern Canada enhances the likelihood of establishing geochronological control on Quaternary stratigraphic records in this region. The pyroclastic deposits associated with the second caldera-forming eruption (C2) consist of loose, granular, airfall and pumice-flow deposits that extend for tens of kilometres beyond Emmons Lake caldera, reaching both the Bering Sea and Pacific Ocean coastlines north and south of the caldera. Geochronological and compositional data on C2 deposits indicate a correlation with the Dawson tephra, a 24 000 14C BP (27 000 calibrated years BP), widespread bed of silicic ash found in loess deposits in west-central Yukon Territory, Canada. The correlation clearly establishes the Dawson tephra as the time-stratigraphic marker of the last glacial maximum.

  17. Elemental content of lichens of the Point Reyes Peninsula, northern California

    USGS Publications Warehouse

    Bennett, J.P.; Benson, S.

    2005-01-01

    The Point Reyes peninsula in northern California is about 45 km northwest of San Francisco and occasionally receives air masses from the city contributing to haze and lowered visibility. Although gaseous pollutants are not a problem, fine particulates containing carbon and other elements are measurable at the park. In this study, five lichen species were sampled along a 40-km linear transect from southeast to northwest from the town of Bolinas at the southern end of the peninsula. Elevated levels of Na and S and the Na/S ratio at localities nearer the ocean confirmed there is a definite marine aerosol influence on lichen elemental content. Elevated potassium and mercury concentrations were also found at high elevation sites that intercept fog. However, arsenic and lead were found to decrease with distance from Bolinas along the transect, suggesting these two elements originate in the fine particulate haze that enters the park from San Francisco. Concentrations of elements were not at enriched levels for other lichen species. A possible local influence of roads on element content needs further study.

  18. Drought variability and change across the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Coll, Joan Ramon; Aguilar, Enric

    2015-04-01

    Drought variability and change is assessed in this study across the Iberian Peninsula along the 20th century and the first decade of the 21st century using state of the art drought indices: the Sc-PDSI, the SPI and the SPEI. Daily temperature and precipitation data from 24 time-series regularly spread over Iberian Peninsula are quality controlled and also homogenized in a monthly scale to create the Monthly Iberian Temperature and Precipitation Series (MITPS) for the period 1906-2010. The Sc-PDSI, the 12-month SPI and 12-month SPEI are computed on a monthly basis using the newly MITPS dataset to identify dry and wet conditions across time. Precipitation data is only required to compute SPI, but potential evapotranspiration (PET) is also needed to perform the Sc-PDSI and SPEI, which is estimated using the Tornthwaite's method. The analysis conducted in this study confirms that drought conditions are worsening for most of the Iberian Peninsula across time strongly induced by global warming especially during the last three decades. All drought indices have found a drying trend in the Pyrenees, Ebro basin, central Iberia and in the south and south-eastern area while a wetting trend is identified in the western and in the north-western region. Future projections also indicate a clear increase in hydrological drought conditions along the 21st century, thus, water saving and the application of effective water management strategies will be crucial to minimize the impact of hydrological droughts over the Iberian Peninsula into the near future. KEY WORDS: Drought, climate change, Iberian Peninsula, drought indices.

  19. Quantification of subaerial and episodic subglacial erosion rates on high latitude upland plateaus: Cumberland Peninsula, Baffin Island, Arctic Canada

    NASA Astrophysics Data System (ADS)

    Margreth, Annina; Gosse, John C.; Dyke, Arthur S.

    2016-02-01

    Long-term rates of subaerial and episodic subglacial erosion by predominately cold-based ice cover are determined for tors on weathered plateaus on Cumberland Peninsula. By measuring terrestrial cosmogenic nuclide concentrations in differentially weathered surfaces on a given tor, we reconstruct the complex exposure and erosion history involving recurring cold-based ice cover. The style and rate of subaerial and subglacial erosion at multiple tor sites on Cumberland Peninsula are assessed with a Monte Carlo approach that computes plausible exposure histories based on a proxy record of global ice volume. Constant subaerial erosion rates by weathering are low (<2 mm ka-1), corroborated by nuclide concentrations measured on two tors located on coastal ridge crests that have likely never been glaciated. Summit plateaus intermittently covered by cold-based ice throughout the Quaternary have experienced episodic subglacial erosion by plucking of fractured bedrock with rates between 1 and 16 mm ka-1. Variation of episodic erosion rates is associated with topographic position of the sampled tors and bedrock fracture density. Most of the tors were last glacially plucked in pre-ultimate glaciations, not during the Wisconsinan glaciation. Furthermore, the new approach provides evidence for the extent of ice coverage during the late Wisconsinan, which is significant if no erratics are available for exposure dating. Despite late Pleistocene intervals of ice cover and glacial plucking, tor-studded landscapes of Cumberland Peninsula are of considerable antiquity.

  20. Wildlife uses and hunting patterns in rural communities of the Yucatan Peninsula, Mexico

    PubMed Central

    2012-01-01

    Background Subsistence hunting is a traditional practice providing food and many other goods for households in the Yucatan Peninsula, southeast Mexico. Economic, demographic, and cultural change in this region drive wildlife habitat loss and local extinctions. Improving our understanding about current practices of wildlife use may support better management strategies for conserving game species and their habitat. We aimed to evaluate if wildlife use remained relevant for the subsistence of rural residents of the Yucatan Peninsula, as well as if local hunting practices were related to environmental, geographical, and cultural factors. Methods Fieldwork was done between March 2010 and March 2011. Information was obtained through conversations, interviews, and participant observation. Record forms allowed recording animals hunted, biomass extracted, distance intervals to hunting sites, habitat types and seasonality of wildlife harvests. Data were analyzed using one-way Analysis of Variance, and Generalized Linear Models. Results Forty-six terrestrial vertebrate species were used for obtaining food, medicine, tools, adornments, pets, ritual objects, and for sale and mitigating damage. We recorded 968 animals taken in 664 successful hunting events. The Great Curassow, Ocellated Turkey, paca, white-tailed deer, and collared peccary were the top harvested species, providing 80.7% of biomass (10,190 kg). The numbers of animals hunted and biomass extracted declined as hunting distances increased from villages. Average per capita consumption was 4.65 ± 2.7 kg/person/year. Hunting frequencies were similar in forested and agricultural areas. Discussion Wildlife use, hunting patterns, and technologies observed in our study sites were similar to those recorded in previous studies for rural Mayan and mestizo communities in the Yucatan Peninsula and other Neotropical sites. The most heavily hunted species were those providing more products and by-products for residents. Large

  1. Continental shelf benthos off Otago Peninsula, New Zealand

    NASA Astrophysics Data System (ADS)

    Probert, P. Keith; Wilson, John B.

    1984-09-01

    Benthic macrofauna of the continental shelf off Otago Peninsula, south-eastern New Zealand (45°51'S, 170°52'E) was surveyed by dredge sampling during 1973-1975. Numerical classification (Canberra metric coefficient and flexible sorting) was used to produce site groups and species groups, and three major benthic communities were recognised: a shallow-water (14-25 m) fauna inhabiting well-sorted fine sand, a mid-shelf fauna (concentrated in the depth range 50-76 m) associated with sediments containing the greatest proportions of gravel and siltclay, and a predominantly sand-bottom fauna occurring mainly on the outer shelf (87-150 m). All station groups were dominated numerically by polychaetes (mean of 36·6-56% of individuals) with Mollusca (13·8-25%) or Crustacea (12·1-19·4%) the next most abundant group. The inshore sand fauna was the most distinct, characteristic elements being the trochid gastropod Antisolarium egenum, an amphipod of the genus Hippomedon and dense patches of the spionid polychaete Spiophanes bombyx. Diagnostic species of the mid-shelf mixed sediments were Lepidonotus jacksoni, Psammolyce antipoda, Lumbrineris brevicirra and Phyllamphicteis foliata (Polychaeta), Terenochiton otagoensis, Micrelenchus caelatus caelatus, Maoricolpus roseus roseus and Zegalerus tenuis (Mollusca), Ampelisca chiltoni (Amphipoda) and Amphipholis squamata (Ophiuroidea). Outer shelf sand stations were faunally less distinct, but among the more characteristic species were Euthalenessa fimbriata, Sigalion sp. and Euchone sp. (Polychaeta) and Gari stangeri (Bivalvia). Several abundant species were widely distributed among station groups, notably Nephtys macroura, Lumbrineris magalhaensis, Phyllochaetopterus socialis and Owenia fusiformis (Polychaeta) and Nucula nitidula and Tawera spissa (Bivalvia). Free-living lunulitiform Bryozoa of the genus Otionella were a characteristic component of inner and outer shelf sand faunas, and their inshore penetration probably marks

  2. Evolution of subsidence styles in forearc basin: example from Cretaceous of southern Vizcaino Peninsula, Baja California, Mexico

    SciTech Connect

    Busby-Spera, C.J.; Boles, J.R.

    1986-04-01

    Late Jurassic to Early Cretaceous arc magmatism is represented by volcaniclastic rocks of the Eugenia Formation in the northern Vizcaino Peninsula and by the metamorphosed Cedros-San Andres volcanoplutonic complex, with a dismembered ophiolitic basement, in the southern peninsula. The Vizcaino Peninsula became the site of forearc sedimentation by the Aptian-Albian (late Early Cretaceous), when arc magmatism moved abruptly eastward to the present-day Peninsular Range. On the southern Vizcaino Peninsula, a conformable stratigraphic section, complicated by later faulting, records a gradual transition from a ridged forearc, broken by basement uplifts and grabens (the Aptian-Albian Asunction Formation), to a broadly subsiding, deep marine forearc basin (the Cenomanian Valle Formation). The basal contact of the Asunction formation has irregular relief caused by brecciated basement rocks and talus accumulated along fault zones. An upward-fining sequence several hundred meters thick records abrupt uplift and gradual denudation of adjacent metamorphic basement. Contemporaneous andesite arc volcanism to the east supplied ash and fresh volcanic detritus to the grabens. Angular sand to boulder-size detritus of the Asunction Formation was derived locally, and includes basic to intermediate meta-igneous rock fragments, with epidote, actinolite, and chlorite, as well as serpentine. Abundant calcareous fossils are commonly unbroken, suggesting local sources for these as well. Angular to subrounded, sand to cobble-sized, intermediate to mafic volcanic rock fragments were derived from a more distant island arc to the east, which occasionally provided intermediate to felsic tuffs to the basin. This source is probably represented by the Aptian-Albian Alisitos Group, which forms much of the western wall of the Late Cretaceous Peninsular Range batholith.

  3. Pan American Airways/Naval Air Transport Service/destroyer base site showing brick ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Pan American Airways/Naval Air Transport Service/destroyer base site showing brick and concrete paving of patio, and circular planters. View facing east. - U.S. Naval Base, Pearl Harbor, Pearl City Peninsula, Pearl City, Honolulu County, HI

  4. Pan American Airways/Naval Air Transport Service/destroyer base site showing stone ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Pan American Airways/Naval Air Transport Service/destroyer base site showing stone wall around patio. View facing east-southeast. - U.S. Naval Base, Pearl Harbor, Pearl City Peninsula, Pearl City, Honolulu County, HI

  5. Hurricane Ike Deposits on the Bolivar Peninsula, Galveston Bay, Texas

    NASA Technical Reports Server (NTRS)

    Evans, Cynthia A.; Wilkinson, M. J.; Eppler, Dean

    2011-01-01

    In September 2008, Hurricane Ike made landfall on Galveston Bay, close to the NASA Johnson Space Center (JSC). The storm flooded much of the area with a storm surge ranging from 11 -20 feet. The Bolivar peninsula, the southeastern coast of Galveston Bay, experienced the brunt of the surge. Several agencies collected excellent imagery baselines before the storm and complementary data a few days afterward that helped define the impacts of the storm. In April of 2011, a team of scientists and astronauts from JSC conducted field mapping exercises along the Bolivar Peninsula, the section of the Galveston Bay coast most impacted by the storm. Astronauts routinely observe and document coastal changes from orbit aboard the International Space Station. As part of their basic Earth Science training, scientists at the Johnson Space Center take astronauts out for field mapping exercises so that they can better recognize and understand features and processes that they will later observe from the International Space Station. Using pre -storm baseline images of the Bolivar Peninsula near Rollover Pass and Gilchrist (NOAA/Google Earth Imagery and USGS aerial imagery and lidar data), the astronauts mapped current coastline positions at defined locations, and related their findings to specific coastal characteristics, including channel, jetties, and other developments. In addition to mapping, we dug trenches along both the Gulf of Mexico coast as well as the Galveston Bay coast of the Bolivar peninsula to determine the depth of the scouring from the storm on the Gulf side, and the amount of deposition of the storm surge deposits on the Bay side of the peninsula. The storm signature was easy to identify by sharp sediment transitions and, in the case of storm deposits, a layer of storm debris (roof shingles, PVC pipes, etc) and black, organic rich layers containing buried sea grasses in areas that were marshes before the storm. The amount of deposition was generally about 20 -25 cm

  6. Antarctic Peninsula Ice Sheet evolution during the Cenozoic Era

    NASA Astrophysics Data System (ADS)

    Davies, Bethan J.; Hambrey, Michael J.; Smellie, John L.; Carrivick, Jonathan L.; Glasser, Neil F.

    2012-01-01

    The Antarctic Peninsula region is currently undergoing rapid environmental change, resulting in the thinning, acceleration and recession of glaciers and the sequential collapse of ice shelves. It is important to view these changes in the context of long-term palaeoenvironmental complexity and to understand the key processes controlling ice sheet growth and recession. In addition, numerical ice sheet models require detailed geological data for tuning and testing. Therefore, this paper systematically and holistically reviews published geological evidence for Antarctic Peninsula Ice Sheet variability for each key locality throughout the Cenozoic, and brings together the prevailing consensus of the extent, character and behaviour of the glaciations of the Antarctic Peninsula region. Major contributions include a downloadable database of 186 terrestrial and marine calibrated dates; an original reconstruction of the LGM ice sheet; and a new series of isochrones detailing ice sheet retreat following the LGM. Glaciation of Antarctica was initiated around the Eocene/Oligocene transition in East Antarctica. Palaeogene records of Antarctic Peninsula glaciation are primarily restricted to King George Island, where glacigenic sediments provide a record of early East Antarctic glaciations, but with modification of far-travelled erratics by local South Shetland Island ice caps. Evidence for Neogene glaciation is derived primarily from King George Island and James Ross Island, where glaciovolcanic strata indicate that ice thicknesses reached 500-850 m during glacials. This suggests that the Antarctic Peninsula Ice Sheet draped, rather than drowned, the topography. Marine geophysical investigations indicate multiple ice sheet advances during this time. Seismic profiling of continental shelf-slope deposits indicates up to ten large advances of the Antarctic Peninsula Ice Sheet during the Early Pleistocene, when the ice sheet was dominated by 40 kyr cycles. Glacials became more

  7. Hurricane Ike Deposits on the Bolivar Peninsula, Galveston Bay, Texas

    NASA Astrophysics Data System (ADS)

    Evans, C. A.; Wilkinson, M. J.; Eppler, D.

    2011-12-01

    In September 2008, Hurricane Ike made landfall on Galveston Bay, close to the NASA Johnson Space Center (JSC). The storm flooded much of the area with a storm surge ranging from 11-20 feet. The Bolivar peninsula, the southeastern coast of Galveston Bay, experienced the brunt of the surge. Several agencies collected excellent imagery baselines before the storm and complementary data a few days afterward that helped define the impacts of the storm. In April of 2011, a team of scientists and astronauts from JSC conducted field mapping exercises along the Bolivar Peninsula, the section of the Galveston Bay coast most impacted by the storm. Astronauts routinely observe and document coastal changes from orbit aboard the International Space Station. As part of their basic Earth Science training, scientists at the Johnson Space Center take astronauts out for field mapping exercises so that they can better recognize and understand features and processes that they will later observe from the International Space Station. Using pre-storm baseline images of the Bolivar Peninsula near Rollover Pass and Gilchrist (NOAA/Google Earth Imagery and USGS aerial imagery and lidar data), the astronauts mapped current coastline positions at defined locations, and related their findings to specific coastal characteristics, including channel, jetties, and other developments. In addition to mapping, we dug trenches along both the Gulf of Mexico coast as well as the Galveston Bay coast of the Bolivar peninsula to determine the depth of the scouring from the storm on the Gulf side, and the amount of deposition of the storm surge deposits on the Bay side of the peninsula. The storm signature was easy to identify by sharp sediment transitions and, in the case of storm deposits, a layer of storm debris (roof shingles, PVC pipes, etc) and black, organic rich layers containing buried sea grasses in areas that were marshes before the storm. The amount of deposition was generally about 20-25 cm; the

  8. Primary production export flux in Marguerite Bay (Antarctic Peninsula): Linking upper water-column production to sediment trap flux

    NASA Astrophysics Data System (ADS)

    Weston, Keith; Jickells, Timothy D.; Carson, Damien S.; Clarke, Andrew; Meredith, Michael P.; Brandon, Mark A.; Wallace, Margaret I.; Ussher, Simon J.; Hendry, Katharine R.

    2013-05-01

    A study was carried out to assess primary production and associated export flux in the coastal waters of the western Antarctic Peninsula at an oceanographic time-series site. New, i.e., exportable, primary production in the upper water-column was estimated in two ways; by nutrient deficit measurements, and by primary production rate measurements using separate 14C-labelled radioisotope and 15N-labelled stable isotope uptake incubations. The resulting average annual exportable primary production estimates at the time-series site from nutrient deficit and primary production rates were 13 and 16 mol C m-2, respectively. Regenerated primary production was measured using 15N-labelled ammonium and urea uptake, and was low throughout the sampling period. The exportable primary production measurements were compared with sediment trap flux measurements from 2 locations; the time-series site and at a site 40 km away in deeper water. Results showed ˜1% of the upper mixed layer exportable primary production was exported to traps at 200 m depth at the time-series site (total water column depth 520 m). The maximum particle flux rate to sediment traps at the deeper offshore site (total water column depth 820 m) was lower than the flux at the coastal time-series site. Flux of particulate organic carbon was similar throughout the spring-summer high flux period for both sites. Remineralisation of particulate organic matter predominantly occurred in the upper water-column (<200 m depth), with minimal remineralisation below 200 m, at both sites. This highly productive region on the Western Antarctic Peninsula is therefore best characterised as 'high recycling, low export'.

  9. Magnetic Properties of Quaternary Deposits, Kenai Peninsula, Alaska -- Implications for Aeromagnetic Anomalies of Upper Cook Inlet

    USGS Publications Warehouse

    Saltus, R.W.; Haeussler, P.J.

    2004-01-01

    We measured magnetic susceptibilities of exposed Quaternary deposits on several beach cliffs and river banks on the Kenai Peninsula near Soldotna, Alaska. Data, descriptions, and photos from nine sites are included in this report. The mean susceptibility for Quaternary materials in this region is approximately 2.5 x 10-3 SI units. This is sufficiently magnetic to produce subtle aeromagnetic anomalies such as those observed to correlate with topographic features in the region of the measurements. The highest susceptibilities measured (greater than 20 x 10-3 SI units) may help, at least in part, to explain moderate amplitude aeromagnetic anomalies observed elsewhere in Cook Inlet, particularly those relating to structures showing Quaternary movement. Comparison of measured beach cliff susceptibility and susceptibility predicted from idealized formulas and two-dimensional cliff models suggests that measured susceptibilies underestimate true bulk susceptibility by 20 percent to 50 percent in this region.

  10. Low-flow characteristics of streams on the Olympic Peninsula, Washington

    USGS Publications Warehouse

    Haushild, W.L.; LaFrance, D.E.

    1977-01-01

    Streams in lowland basins of the Olympic Peninsula, Washington, generally have their low flows in summer and peak flows in winter, whereas streams originating at higher elevations in the mountains have their low flows in late summer-early fall and they have both winter and spring peak flows. Data from long-term stations indicate no important trend in low flows during 1940-73 but they do indicate that low flows generally were lower during the relatively dry 1940 's than during the relatively wet 1950-73 period. The magnitude and frequency of 7-day low flows were estimated for 116 sites either from frequency analyses of a data at long-term stations or from correlation of data at a short-term station with data at an appropriate long-term station. (Woodard-USGS)

  11. Elemental composition of Usnea sp lichen from Potter Peninsula, 25 de Mayo (King George) Island, Antarctica.

    PubMed

    Bubach, Débora; Catán, Soledad Perez; Di Fonzo, Carla; Dopchiz, Laura; Arribére, Maria; Ansaldo, Martin

    2016-03-01

    Several pollutants, which include metals, are present in the Antarctic atmosphere, snow, marine and terrestrial organisms. This work reports the elements incorporated by Usnea sp thalli in Potter Peninsula, 25 de Mayo (King George) Island, South Shetlands, Antarctica. Geological origin was analyzed as possible sources of elements. For this purpose, correlations were done using a geochemical tracer, principal component analysis and enrichment factors were computed. Lithophile elements from particulate matter were present in most of the sampling sites. Bromine, Se and Hg showed the highest enrichment factors suggesting other sources than the particulate matter. Mercury values found in Usnea sp were in the same range as those reported for Deception Island (South Shetlands) and remote areas from the Patagonia Andes. PMID:26741560

  12. High shrew diversity on Alaska's Seward Peninsula: Community assembly and environmental change

    USGS Publications Warehouse

    Hope, Andrew G.

    2012-01-01

    In September 2010, 6 species of shrews (genus: Sorex) were collected at a single locality on the Seward Peninsula of Alaska. Such high sympatric diversity within a single mammalian genus is seldom realized. This phenomenon at high latitudes highlights complex Arctic community dynamics that reflect significant turnover through time as a consequence of environmental change. Each of these shrew species occupies a broad geographic distribution collectively spanning the entire Holarctic, although the study site lies within Eastern Beringia, near the periphery of all individual ranges. A review of published genetic evidence reflects a depauperate shrew community within ice-free Beringia through the last glaciation, and recent assembly of current diversity during the Holocene.

  13. Bathymetric-based habitat model for yelloweye rockfish (Sebastes ruberrimus) on Alaska's outer Kenai Peninsula

    NASA Astrophysics Data System (ADS)

    Mumm, Joshua D.

    Motivated primarily as part of a habitat-based stock assessment, we explored the feasibility of modeling yelloweye rockfish (Sebastes ruberrimus) habitat in Southcentral Alaska using high-resolution multibeam bathymetry. A generalized linear model was developed with bathymetrically derived terrain metrics (rugosity, slope, bathymetric position index, and distance-to-rock) as predictor variables. The model was parameterized and validated using remotely operated vehicle observations. When evaluated for the Chiswell Island training area, the model correctly classified 96.0% (n = 100) of a reserved set of presence/absence validation points (Cohen's Kappa = 0.92; AUC = 0.98). When evaluated for the independent Nuka Island testing area, the overall accuracy was 82.5% (n=332; Kappa = 0.65; AUC = 0.95). This study demonstrates that suitable yelloweye habitat can be modeled with reasonable accuracy using high-resolution multibeam bathymetry, and such a model is fairly portable among sites along the Kenai Peninsula's outer coast.

  14. Exploring the vents, ridges, rocks, and geothermal spas of the Reykjanes Peninsula

    NASA Astrophysics Data System (ADS)

    Ramsayer, Kate

    2012-07-01

    Renting a submarine to explore the deepsea basalt lava flows of the Mid-Atlantic Ridge is a pricey proposition. But on a field trip to Iceland's Reykjanes Peninsula following the Chapman Conference on Volcanism and the Atmosphere, participants were able to stay on dry land to explore the volcanic features of the ridge where the Eurasian and North American plates are spreading apart. "If you're interested in ocean ridge basalt, the Reykjanes Ridge is your place," said Karl Grönvold, a geochemist with the Institute of Earth Sciences at the University of Iceland. Grönvold led the daylong field trip to geologic sites of interest in southwest Iceland, including the ridge, fumaroles, boiling hot pots, and the geothermal spa and power plant at the Blue Lagoon.

  15. Modelling Chemical Patterns of Atmospheric Polycyclic Aromatic Hydrocarbons (PAHs) in the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Ratola, Nuno; Jiménez-Guerrero, Pedro

    2013-04-01

    Semi-volatile organic compounds (SVOCs) such as PBDEs, PCBs, organochlorine pesticides (OCPs) or PAHs, are widespread and generated in a multitude of anthropogenic (and natural for PAHs) processes and although they are found in the environment at low concentrations, possess an extraordinary carcinogenic capacity (Baussant et al., 2001) and high ecotoxicity due to their persistence in different matrices (air, soil, water, living organisms). In particular, PAHs are originated by combustion processes or release from fossil fuels and can be transported in the atmosphere over long distances in gaseous or particulate matter (Baek et al., 1991). The establishment of strategies for sampling and chemical transport modelling of SVOCs in the atmosphere aiming the definition and validation of the spatial, temporal and chemical transport patterns of contaminants can be achieved by an integrated system of third-generation models that represent the current state of knowledge in air quality modelling and experimental data collected in field campaigns. This has implications in the fields of meteorology, atmospheric chemistry and even climate change. In this case, an extensive database already obtained on levels of atmospheric PAHs from biomonitoring schemes in the Iberian Peninsula fuelled the establishment of the first models of behaviour for PAHs. The modelling system WRF+CHIMERE was implemented with high spatial and temporal resolution to the Iberian Peninsula in this first task (9 km for the Iberian Peninsula, 3 km to Portugal, 1 hour), using PAHs atmospheric levels collected over a year-long sampling scheme comprising 4 campaigns (one per season) in over 30 sites. Daily information on meteorological parameters such as air temperature, humidity, rainfall or wind speed and direction was collected from the weather stations closest to the sampling sites. Diagnosis and forecasts of these meteorological variables using MM5 or WRF were used to feed a chemistry transport model

  16. Distribution of Radioactive Materials in the Absheron Peninsula, Azerbaijan - 13567

    SciTech Connect

    Vandergraaf, Tjalle T.; Mamedov, Gudrat G.; Ramazanov, Mahammadali A.; Badalov, Vatan H.; Naghiyev, Jalal A.; Mehdiyeva, Afat A.

    2013-07-01

    The Absheron Peninsula forms the extreme Eastern part of Azerbaijan and juts into the Caspian Sea. The region has a long history of oil and gas exploration, transport, and processing and includes a number of abandoned chemical plants that were used in the separation of iodine from formation waters. As a result of lax environmental standards during the Soviet era, the industrial activity has led to serious contamination from oils residues, heavy metals and naturally occurring radioactive materials (NORM). Radiometric surveys performed over a wide range of the Absheron Peninsula showed generally low NORM concentrations. However, radiation levels two to three orders of magnitude above background levels were detected at two abandoned iodine separation plants near the capital city, Baku. These elevated radiation levels are mainly due to Ra-226 and U-238 with lower contributions from Ra-228 and U-235. (authors)

  17. Evaluation Of Elastic Strain Accumulation In The Southern Indian Peninsula By GPS-Geodesy

    NASA Astrophysics Data System (ADS)

    Narayanababu, R.; Ec, M.; Tummala, C.

    2004-12-01

    The computed elastic strain accumulation in the southern Indian peninsula from the GPS derived velocity fields of the global network of GPS stations, in and around the Indian plate which includes Maitri, Indian Antarctic Station, show a significant departure from rigid plate behaviour in a manner consistent with the mapped intra plate stress field, observations of deformations and seismicity in the region. Our results of intraplate strain accumulation within Antarctica Plate covering three sites MAIT, CAS1 and DAV1 are 1.8x10-9yr-1, 1.6x10-9yr-1 and 1.1x10-9yr-1, respectively. Similarly, the estimates of interplate strain accumulation between Antarctica and other plates Somalia (SEY1), Africa (HARO), Australia (YAR1), and diffuse plate boundary between India and Australia (COCO) are found to be 1.1x10-9yr-1, 1.0x10-10yr-1, 1.27x10-8yr-1 and 1.18x10-8yr-1, respectively. These estimates are in good agreement with the earlier studies on estimation of global strain rate. The combined GPS and seismic analysis confirm the emergence of diffuse plate boundary between India and Australia and relates to the late Miocene Himalayan uplift. The calculated stress field in the West of the Indian Peninsula has a roughly N-S directed tensional and E-W oriented compressional character and the velocity vectors of all other sites throw a significant insight into the plausible causes of the strain accumulation processes in the Indian Ocean and the northward movement of Indian plate.

  18. Ground-water flow and water quality in the sand aquifer of Long Beach Peninsula, Washington

    USGS Publications Warehouse

    Thomas, B.E.

    1995-01-01

    This report describes a study that was undertaken to improve the understanding of ground-water flow and water quality in the coastal sand aquifer of the Long Beach Peninsula of southwestern Washington. Data collected for the study include monthly water levels at 103 wells and 28 surface-water sites during 1992, and water-quality samples from about 40 wells and 13 surface-water sites in February and July 1992. Ground water generally flows at right angles to a ground-water divide along the spine of the low-lying peninsula. Historical water-level data indicate that there was no long-term decline in the water table from 1974 to 1992. The water quality of shallow ground water was generally good with a few local problems. Natural concentrations of dissolved iron were higher than 0.3 milligrams per liter in about one-third of the samples. The dissolved-solids concentrations were generally low, with a range of 56 to 218 milligrams per liter. No appreciable amount of seawater has intruded into the sand aquifer, chloride concentrations were low, with a maximum of 52 milligrams per liter. Agricultural activities do not appear to have significantly affected the quality of ground water. Concentrations of nutrients were low in the cranberry-growing areas, and selected pesticides were not found above the analytical detection limits. Septic systems probably caused an increase in the concentration of nitrate from medians of less than 0.05 milligrams per liter in areas of low population density to 0.74 milligrams per liter in areas of high density.

  19. Prokaryotic Community in Lacustrine Sediments of Byers Peninsula (Livingston Island, Maritime Antarctica).

    PubMed

    Gugliandolo, Concetta; Michaud, Luigi; Lo Giudice, Angelina; Lentini, Valeria; Rochera, Carlos; Camacho, Antonio; Maugeri, Teresa Luciana

    2016-02-01

    Byers Peninsula (Livingston Island, Antarctica), the largest seasonally ice-free region of the Maritime Antarctica, holds a large number of lakes, ponds, and streams. The prokaryotic structure and bacterial diversity in sediment samples collected during the 2008-2009 austral summer from five inland lakes, two coastal lakes, and an estuarine site were analyzed by Catalyzed Reporter Deposition Fluorescence In Situ Hybridization (CARD-FISH) and 16S rRNA 454 tag pyrosequencing techniques, respectively. Differently from inland lakes, which range around the oligotrophic status, coastal lakes are eutrophic environments, enriched by nutrient inputs from marine animals. Although the prokaryotic abundances (estimated as DAPI stained cells) in sediment samples were quite similar among inland and coastal lakes, Bacteria always far dominated over Archaea. Despite the phylogenetic analysis indicated that most of sequences were affiliated to a few taxonomic groups, mainly referred to Proteobacteria, Bacteroidetes, and Actinobacteria, their relative abundances greatly differed from each site. Differences in bacterial composition showed that lacustrine sediments were more phyla rich than the estuarine sediment. Proteobacterial classes in lacustrine samples were dominated by Betaproteobacteria (followed by Alphaproteobacteria, Deltaproteobacteria, and Gammaproteobacteria), while in the estuarine sample, they were mainly related to Gammaproteobacteria (followed by Deltaproteobacteria, Epsilonproteobacteria, Alphaproteobacteria, and Betaproteobacteria). Higher number of sequences of Alphaproteobacteria, Cyanobacteria, Verrucomicrobia, and Planctomycetes were observed in sediments of inland lakes compared to those of coastal lakes, whereas Chloroflexi were relatively more abundant in the sediments of coastal eutrophic lakes. As demonstrated by the great number of dominant bacterial genera, bacterial diversity was higher in the sediments of inland lakes than that in coastal lakes

  20. Fossils from bore holes on the Eastern Shore Peninsula, Virginia

    USGS Publications Warehouse

    Todd, Ruth; Gardner, Julia A.; Sohn, I.G.

    1955-01-01

    This report lists Foraminifera, Mollusca, and Ostracoda in five bore holes that penetrated a maximum of 445 feet of section in sediments of Pleistocene and Miocene age, and discusses the paleoecologic and stratigraphic significance of the fossils. It includes the contents of references 6, 16, and 18 of Virginia Division of Geology Mineral Resources Circular No. 2, dealing with the geology and groundwater resources of the Eastern Shore peninsula.

  1. Spatial and temporal variability of periglaciation of the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Oliva, M.; Serrano, E.; Gómez-Ortiz, A.; González-Amuchastegui, M. J.; Nieuwendam, A.; Palacios, D.; Pérez-Alberti, A.; Pellitero-Ondicol, R.; Ruiz-Fernández, J.; Valcárcel, M.; Vieira, G.; Antoniades, D.

    2016-04-01

    Active periglacial processes are currently marginal in the Iberian Peninsula, spatially limited to the highest mountain ranges. However, a wide variety of periglacial deposits and landforms are distributed in low and mid-altitude environments, which shows evidence of past periods of enhanced periglacial activity. The purpose of this paper is to summarize the present knowledge of past periglacial activity in the Iberian Peninsula. The chronological framework takes four main stages into account: the last glaciation, deglaciation, Holocene and present-day processes. This study focuses on the highest massifs (Pyrenees, Cantabrian Range, NW ranges, Central Range, Iberian Range, Sierra Nevada) as well as other lower elevation environments, namely the central Iberian Meseta. During the last glaciation the periglacial belt extended to much lower altitudes than today, reaching current sea level in the NW corner of the Iberian Peninsula. A wide range of geomorphological landforms and sedimentary records is indicative of very active periglacial processes during that phase, in some cases related to permafrost conditions (i.e., block streams, rock glaciers). Most of the inactive landforms and deposits in low and mid-elevations in Iberia are also related to this phase. The massive deglaciation of the Iberian massifs was caused by a gradual increase in temperatures. The deglaciation phase was only interrupted by a short period with colder conditions (the Younger Dryas) that reactivated periglacial processes in the formerly glaciated cirques of the highest lands, specifically with the widespread development of rock glaciers. During the Holocene, periglacial processes have been only active in the highest ranges, shifting in altitude according to temperature regimes and moisture conditions. The Little Ice Age saw the reactivation of periglacial activity in lower elevations than today. Currently, periglacial processes are only active in elevations exceeding 2500 m in the southern

  2. Holocene records of geomagnetic field behavior from a north-south transect along the western Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Brachfeld, S. A.; Shah, D. P.; St-Onge, M.; St-Onge, G.

    2013-12-01

    Geochronology is inherently difficult when working with Antarctic margin sediments. Radiocarbon dating and oxygen isotope stratigraphy are challenging or impossible in sites with poor preservation of biogenic calcite. Radiocarbon dating of the acid insoluble organic matter (AIOM) is further complicated by organically lean sediment and the presence of reworked organic carbon or detrital carbon from sedimentary rocks. These complications limit the ability to interpret a paleoclimate record. Geomagnetic paleointensity dating is a proven 'tuning' technique that has been successfully applied in several studies around the Antarctic margin. However, the reference curves to which these sites were tuned were constructed primarily from Northern Hemisphere data. Here we present paleomagnetic secular variation (PSV) and relative paleointensity (RPI) data from three Antarctic Peninsula sites that possess independent chronologies and which have moderate to ultra-high sedimentation rates (40 - 700 cm/ka). Maxwell Bay, located in the volcanic South Shetland Islands, is an ultra-high-resolution site with strongly magnetic sediments from which the Shallow Drilling (SHALDRIL) program recovered a 108-m record spanning the last 14 ka. Outer Barilari Bay and Hugo Island Trough, which lie to the South along the western Antarctic Peninsula, are moderate resolution sites with a high proportion of biogenic silica. Maxwell Bay and Bariliari Bay are unique in that they possess homogenous sediment and uniform magnetic mineral assemblages, while also preserving biogenic calcite, a rare combination on the Antarctic margin. All three sites preserve strong, stable remanent magnetizations with an easily isolated characteristic component and MAD values generally < 2°, with the exception of turbidites, intervals with abundant dropstones, and biosiliceous ooze intervals. Inclination values fluctuate between the present-day value at the cores sites (-58°) and the geomagnetic axial dipole inclination

  3. Mapping the HLA diversity of the Iberian Peninsula.

    PubMed

    Romòn, Iñigo; Montes, Carmen; Ligeiro, Dario; Trindade, Hélder; Sanchez-Mazas, Alicia; Nunes, José Manuel; Buhler, Stéphane

    2016-10-01

    The polymorphism of HLA genes can be used to reconstruct human peopling history. However, this huge diversity impairs successful matching in stem cell transplantation, a situation which has led to the recruitment of millions of donors worldwide. In parallel to the increase of recruitment, registries are progressively relying on information from population genetics to optimize their donor pools in terms of HLA variability. In this study, the HLA data of 65,000 Spanish bone marrow donors were analyzed together with 60,000 Portuguese individuals to provide a comprehensive HLA genetic map of the Iberian Peninsula. The frequencies of many alleles were shown to vary continuously across the Peninsula, either increasing or decreasing from the Mediterranean coast to the Atlantic domain or from the Strait of Gibraltar to the Pyrenees and Bay of Biscay. Similar patterns were observed for several haplotypes. In addition, within some regions neighboring provinces share a close genetic similarity. These results outline the genetic landscape of the Iberian Peninsula, and confirm that the analysis of the HLA polymorphism may reveal relevant signatures of past demographic events even when data from donor registries are used. This conclusion stimulates future developments of the Spanish registry, presented here for the first time. PMID:27377016

  4. Coastal-Change and Glaciological Maps of the Antarctic Peninsula

    USGS Publications Warehouse

    Ferrigno, Jane G.; Williams, Richard S., Jr.; Thomson, Janet W.

    2002-01-01

    In 2000, the Glacier Studies Project (GSP) of the U.S. Geological Survey (USGS) and the Mapping and Geographic Information Centre (MAGIC) of the British Antarctic Survey (BAS) began a formal cooperative 3-year endeavor to prepare three maps of the Antarctic Peninsula region. The maps will be based on a large variety of cartographic, aerial photograph, satellite image, and ancillary historical datasets archived at each institution. The maps will document dynamic changes on the peninsula during the past 50 years. The three maps are part of a planned 24-map series (I-2600) being published by the USGS in both paper and digital format (see USGS Fact Sheet FS-050-98 at http://pubs.usgs.gov/factsheet/fs50-98/); the maps are of the Trinity Peninsula area (I-2600-A), the Larsen Ice Shelf area (I-2600-B), and the Palmer Land area (I-2600-C). The 1:1,000,000-scale maps will encompass an area 1,800 kilometers (km) long and with an average width of 400 km (range of 200 to 600 km wide); the area is between lats 60? and 76? S. and longs 52? and 80? W. Each of the three maps will include an interpretive booklet that analyzes documented historical changes in the fronts of the ice shelves and termini of the outlet glaciers.

  5. Preliminary assessment of aridity conditions in the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Andrade, C.; Corte-Real, J. A.

    2016-06-01

    Aridity is one of the key elements characterizing the climate of a region, having a severe impact on human activities. Aiming at assessing aridity conditions in the Iberian Peninsula, the spatial distribution of the UNEP aridity index is analyzed during the period 1901-2012. Gridded precipitation and potential evapotranspiration datasets are used on a monthly basis. Results show that the southern half of Iberia is particularly vulnerable to water stress and hence to desertification processes. In particular, the UNEP aridity index reveals an increase and northward extension of the semi-arid regime in the Iberian Peninsula between 1901 and 2012. More than 50% of the north and western territory have experienced humid/sub-humid conditions, while the other regions underwent semi-arid settings. Results also reveal that climate was subjected to spatial and temporal variabilities with an overall statistically significant (at a 95% confidence level) trend to aridification in the south-easternmost and central regions. The remaining territory of the Iberian Peninsula does not reveal statistically significant trends.

  6. Severe dust storms over the Arabian Peninsula: Observations and modeling

    NASA Astrophysics Data System (ADS)

    shalaby, ahmed

    2014-05-01

    Dust aerosols and dust storms have tremendous effects on human health and all development activities. Also atmospheric dust plays a major role in the Earth climate system by its interaction with radiation and clouds. Severe dust storms are considered the severest phenomena in the Arabian Peninsula, since they are occurring all the year round with maximum activity and frequency in Summer. The Regional Climate Model (RegCM4) has been used to simulate severe dust storms events in the Arabian Peninsula from 1998 up to 2011. This long period simulation shows a typical pattern and dynamical features of the large-scale severe dust storm in winter seasons and summer seasons. The Aerosol Optical Depth (AOD) from the model outputs have been compared against ground--base observations of three AERONET stations (i.e., Kuwait, Mazeria and Solar-Village) and daily space--based observations of MISR, Deepblue and OMI. The dynamical analysis of the large—scale severe dust storms reveal the difference between winter time storms and summer time storm. Winter time storm occurs when the cold air front in the north is coupled with the extension of the Red Sea trough from the south. However, the summer time storm is associated with strong Shamal wind that extend from northern Kuwait to the southern Arabian Peninsula.

  7. Rate of collisional deformation in Kamchatsky Peninsula, Kamchatka

    NASA Astrophysics Data System (ADS)

    Kozhurin, A. I.; Pinegina, T. K.; Ponomareva, V. V.; Zelenin, E. A.; Mikhailyukova, P. G.

    2014-03-01

    Detailed data are discussed on the rate of Holocene horizontal and vertical movements along a fault in the southeastern Kamchatsky Peninsula, which is situated between the converging Aleutian and Kamchatka island arcs. The fault is the northern boundary of the block invading into the peninsula under pressure of the Komandorsky Block of the Aleutian arc. The rate of right-lateral slip along the fault was increasing in the Holocene and reached 18-19 mm/yr over the last 2000 years and 20 mm/yr by contemporary time. Comparison of these estimates with those that follow from offsets of older rocks also indicates acceleration of horizontal movements along the fault from the early Quaternary to the present. The results obtained from rates of GPS station migration show that about half the rate of the northwestern drift of the Komandorsky Block is consumed for movement of the block of the southern side of the fault. The remainder of movement of the Komandorsky Block is consumed for movements (probably, underthrusting) at the eastern continental slope of the Kamchatsky Peninsula.

  8. Earthquake induced landslide hazard field observatory in the Avcilar peninsula

    NASA Astrophysics Data System (ADS)

    Bigarre, Pascal; Coccia, Stella; Theoleyre, Fiona; Ergintav, Semih; Özel, Oguz; Yalçinkaya, Esref; Lenti, Luca; Martino, Salvatore; Gamba, Paolo; Zucca, Francesco; Moro, Marco

    2015-04-01

    Earthquake-triggered landslides have an increasing disastrous impact in seismic regions due to the fast growing urbanization and infrastructures. Just considering disasters from the last fifteen years, among which the 1999 Chi-Chi earthquake, the 2008 Wenchuan earthquake, and the 2011 Tohoku earthquake, these events generated tens of thousands of coseismic landslides. Those resulted in amazing death toll and considerable damages, affecting the regional landscape including its hydrological main features. Despite a strong impetus in research during past decades, knowledge on those geohazards is still fragmentary, while databases of high quality observational data are lacking. These phenomena call for further collaborative researches aiming eventually to enhance preparedness and crisis management. The MARSITE project gathers research groups in a comprehensive monitoring activity developed in the Sea of Marmara Region, one of the most densely populated parts of Europe and rated at high seismic risk level since the 1999 Izmit and Duzce devastating earthquakes. Besides the seismic threat, landslides in Turkey and in this region constitute an important source of loss. The 6th Work Package of MARSITE project gathers 9 research groups to study earthquake-induced landslides focusing on two sub-regional areas of high interest among which the Cekmece-Avcilar peninsula, located westwards of Istanbul, as a highly urbanized concentrated landslide prone area, showing high susceptibility to both rainfalls while affected by very significant seismic site effects. A multidisciplinary research program based on pre-existing studies has been designed with objectives and tasks linked to constrain and tackle progressively some challenging issues related to data integration, modeling, monitoring and mapping technologies. Since the start of the project, progress has been marked on several important points as follows. The photogeological interpretation and analysis of ENVISAT-ERS DIn

  9. Glacial Geomorphic Characteristics of the Antarctic Peninsula Fjords

    NASA Astrophysics Data System (ADS)

    Wellner, J. S.; Munoz, Y. P.; Mead, K. A.; Hardin, L. A.

    2011-12-01

    A distinctive suite of subglacial geomorphic features, representing the grounding of an ice sheet and its subsequent retreat, has been well documented for many parts of the Antarctic continental shelf. Geomorphic features include meltwater channels, drumlins, mega-scale glacial lineations, and gullies cut into the upper slope. Many of these same features occur in more recently deglaciated fjords, but at different scales and in different combinations. We have surveyed twelve fjords on the Antarctic Peninsula, from the Graham Land Coast to Hope Bay as well as on Anvers Island and in the South Shetland Islands. Surveys include multibeam swath bathymetry, CHIRP 3.5 kHz seismic, and sediment cores. Recently, we have reprocessed much of the multibeam data using new software allowing higher-resolution imagery. Unlike on the outer continental shelf of the Antarctic Peninsula, where there is a relatively simple suite of geomorphic features and a uniform retreat history, the fjords on the inner shelf show a complex geomorphic pattern representing somewhat unique glacial retreat histories for each fjord. Several fjords have distinctive grounding zone wedge deposits, and some fjords have such wedges in multiple locations, representing multiple pauses in the retreat history, or a stepped retreat of the ice. Drumlins and mega-scale glacial lineations are present in the fjords, but extend for kms rather than the tens of kms that are typical of the outer shelf. If drumlins are interpreted to indicate acceleration of grounded ice, as they are on the outer shelf, then there must have been multiple zones of acceleration across the flow path of the ice as drumlin sets occur in multiple zones in a single flow path. The inner parts of many fjords along the coast of the peninsula are characterized by features interpreted as erosional meltwater channels, although such features are not common in fjords in the islands off the peninsula, despite the similar scale of the fjords themselves

  10. Study of Tropospheric ozone (TOR) variability over Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Kulkarni, Pavan; Bortoli, Daniele; Salgado, Rui; Antón, Manuel; João Costa, Maria; Silva, Ana Maria

    2010-05-01

    To study tropospheric ozone (O3) variability and the increase in the number of months with higher tropospheric O3 concentration over the Iberian Peninsula, NASA Langley Tropospheric Ozone Residual (TOR) data has been analyzed for the 1979-2005 period. The maximum tropospheric O3 amount over the entire Iberian Peninsula was found in June (~41 DU) and a minimum in December (~29 DU). Over North Atlantic Coast (NAC) and Mediterranean Coast (MC) the maximum tropospheric O3 amount was found in July (~41 DU) and June (~42 DU) and the minimum was found in December (~28 DU and ~30 DU, respectively). The West Atlantic Coast (WAC), Pyrenees Mountain Range (PMR) and Central Iberian Peninsula (CIP) have an extended period of maximum tropospheric O3 amount, during June and July over WAC (~44 DU) and PMR (~39 DU), and during May, June and July over CIP (~40 DU). Similarly, WAC, PMR and CIP have an extended period of minimum tropospheric O3 amount, during December and January over WAC (~30 DU) and CIP (~29 DU) and November and December over PMR (~28 DU). The high concentration of ozone in July over the Atlantic Ocean near Iberian Peninsula are due to the presence of Azores anticyclone, extending in ridge through the Cantabrian Sea to the British Isles and West and Central Europe, and related photochemistry and dynamics, has profound effect on the observed higher ozone concentration over WAC zone. Strong seasonal cycle in tropospheric O3 amount has been observed with large variation over NAC (~49%), followed by WAC (~48%) and MC (~41%) compared to CIP and PMR (~38%). When the data are compared over the Iberian Peninsula for the two periods (1979-1993 and 1997-2005), a systematic increase in the number of months with higher tropospheric O3 concentration has been observed during the second period with respect to the first. These increases are almost 8% to 24% over NAC, 6% to 17% over WAC, 5% to 24% over CIP, 6% to 23% over MC and 13% to 18% over PMR. It has been observed that

  11. Status and distribution of the Kittlitz's Murrelet Brachyramphus brevirostris along the Alaska Peninsula and Kodiak and Aleutian Islands, Alaska

    USGS Publications Warehouse

    Madison, Erica N.; Piatt, John F.; Arimitsu, Mayumi L.; Romano, Marc D.; van Pelt, Thomas I.; Nelson, S. Kim; Williams, Jeffrey C.; DeGange, Anthony R.

    2011-01-01

    The Kittlitz's Murrelet Brachyramphus brevirostris is adapted for life in glacial-marine ecosystems, being concentrated in the belt of glaciated fjords in the northern Gulf of Alaska from Glacier Bay to Cook Inlet. Most of the remaining birds are scattered along coasts of the Alaska Peninsula and Aleutian Islands, where they reside in protected bays and inlets, often in proximity to remnant glaciers or recently deglaciated landscapes. We summarize existing information on Kittlitz's Murrelet in this mainly unglaciated region, extending from Kodiak Island in the east to the Near Islands in the west. From recent surveys, we estimated that ~2400 Kittlitz's Murrelets were found in several large embayments along the Alaska Peninsula, where adjacent ice fields feed silt-laden water into the bays. On Kodiak Island, where only remnants of ice remain today, observations of Kittlitz's Murrelets at sea were uncommon. The species has been observed historically around the entire Kodiak Archipelago, however, and dozens of nest sites were found in recent years. We found Kittlitz's Murrelets at only a few islands in the Aleutian chain, notably those with long complex shorelines, high mountains and remnant glaciers. The largest population (~1600 birds) of Kittlitz's Murrelet outside the Gulf of Alaska was found at Unalaska Island, which also supports the greatest concentration of glacial ice in the Aleutian Islands. Significant populations were found at Atka (~1100 birds), Attu (~800) and Adak (~200) islands. Smaller numbers have been reported from Unimak, Umnak, Amlia, Kanaga, Tanaga, Kiska islands, and Agattu Island, where dozens of nest sites have been located in recent years. Most of those islands have not been thoroughly surveyed, and significant pockets of Kittlitz's Murrelets may yet be discovered. Our estimate of ~6000 Kittlitz's Murrelets along the Alaska Peninsula and Aleutian Islands is also likely to be conservative because of the survey protocols we employed (i.e. early

  12. Soils and landforms from Fildes Peninsula and Ardley Island, Maritime Antarctica

    NASA Astrophysics Data System (ADS)

    Michel, Roberto F. M.; Schaefer, Carlos E. G. R.; López-Martínez, Jerónimo; Simas, Felipe N. B.; Haus, Nick W.; Serrano, Enrique; Bockheim, James G.

    2014-11-01

    Fildes Peninsula (F.P.) and Ardley Island (A.I.) are among the first ice-free areas in Maritime Antarctica. Since the last glacial retreat in this part of Antarctica (8000 to 5000 years BP), the landscape in these areas evolved under paraglacial to periglacial conditions, with pedogenesis marked by cryogenic processes. We carried out a detailed soil and geomorphology survey, with full morphological and analytical description for both areas; forty-eight soil profiles representing different landforms were sampled, analyzed and classified according to the U.S. Soil Taxonomy and the World Reference Base for Soil Resources (WRB). Soils are mostly turbic, moderately developed, with podzolization and strong phosphatization (chemical weathering of rock minerals and formation of amorphous Al and Fe minerals) in former ornithogenic sites while in areas with poor vegetation show typical features of cryogenic weathering. Nivation, solifluction, cryoturbation, frost weathering, ablation and surface erosion are widespread. The most represented landform system by surface in Fildes Peninsula is the periglacial one, and 15 different periglacial landforms types have been identified and mapped. These features occupy about 30% of the land surface, in which patterned ground and stone fields are the most common landforms. Other significant landforms as protalus lobes, rock glaciers or debris lobes indicate the extensive presence of permafrost. Soil variability was high, in terms of morphological, physical and chemical properties, due to varying lithic contributions and mixing of different rocks, as well as to different degrees of faunal influence. Three soil taxonomy orders were identified, whereas thirty four individual pedons were differentiated. Fildes Peninsula experiences a south-north gradient from periglacial to paraglacial conditions, and apparently younger soils and landforms are located close to the Collins Glacier. Arenosols/Entisols and Cryosols/Gelisols (frequently

  13. Ice flow velocities and elevation change at Fleming Glacier, Wordie Ice Shelf, Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Wendt, A.; Wendt, J.; Bown, F.; Rivera, A.; Zamora, R.; Bravo, C.; Casassa, G.

    2009-04-01

    Glaciers in the Antarctic Peninsula have been responding to the pronounced atmospheric warming in the region (Vaughan et al. 2003) with frontal retreat (Cook et al. 2005), ice shelf collapse (Rott et al. 1996) and ice flow acceleration and thinning (Rignot et al. 2004; Shepherd et al. 2003; Pritchard & Vaughan 2007). These trends have progressively migrated southwards along the Antarctic Peninsula causing, for instance, a substantial retreat of Wilkins Ice Shelf (70.2˚ S) in 2008. At 69.3˚ S, but 300 km to the east, Wordie Ice Shelf experienced a major reduction in size in the 1980s (Doake & Vaughan 1991). Available information about this ice shelf and its feeding glaciers dates back to the 1970s when ice thickness and velocity measurements were carried out on Fleming Glacier (Doake 1975). Although initially it was thought that the post-collapse conditions of the feeding glaciers remained unchanged (Vaughan 1993), more recent evidence shows that glaciers accelerated after the ice shelf collapse and substantial glacier thinning has occurred (Rignot et al. 2005). We present data acquired during two field expeditions to Fleming Glacier. During the first season in November 2007, we installed an Automatic Weather Station (AWS) and a permanent GPS site. Additional data including a local GPS network, ground penetrating radar measurements and snow densities were collected. In December 2008, during the second field campaign, surface elevation data were acquired using an airborne laser scanner along a trajectory between Gibbs Glacier and Airy Glacier, along the ice divide between both sides of the Peninsula and on Fleming Glacier. The AWS was found protruding only 20 cm above the snow surface, demonstrating the high snow accumulation in the area, which was sufficient to cover the 4 m high tower installed in 2007 and that annual variability in the mass accumulation is significant. The station collected data for 250 days. The permanent GPS stopped collecting data after

  14. An annotated checklist of the Chilopoda and Diplopoda (Myriapoda) of the Abrau Peninsula, northwestern Caucasus, Russia

    PubMed Central

    Semenyuk, Irina I.; Tuf, Ivan H.

    2016-01-01

    Abstract Background The Abrau Peninsula is located in northwestern Caucasus between the cities of Novorossiysk and Anapa, Krasnodar Province, Russia. This paper contains an annotated checklist of the Chilopoda and Diplopoda inhabiting the Abrau Peninsula. New information The fauna of the Abrau Peninsula comprises 17 centipede (4 orders) and 16 millipede (6 orders) species. Henia taurica, hitherto known only from the Crimea, has now been reported from several localities in the studied region. The study also reveals two possibly new millipede species. Statistical analyses showed that habitat preferences of myriapod species within the Abrau Peninsula are caused by species geographic distribution pattern and microbiotope preferences. PMID:27346949

  15. Comparison of multi-proxy data with past1000 model output over the Terminal Classic Period (800-1000 A.D.) on the Yucatan Peninsula.

    NASA Astrophysics Data System (ADS)

    Van Pelt, S.; Kohfeld, K. E.; Allen, D. M.

    2015-12-01

    The decline of the Mayan Civilization is thought to be caused by a series of droughts that affected the Yucatan Peninsula during the Terminal Classic Period (T.C.P.) 800-1000 AD. The goals of this study are two-fold: (a) to compare paleo-model simulations of the past 1000 years with a compilation of multiple proxies of changes in moisture conditions for the Yucatan Peninsula during the T.C.P. and (b) to use this comparison to inform the modeling of groundwater recharge in this region, with a focus on generating the daily climate data series needed as input to a groundwater recharge model. To achieve the first objective, we compiled a dataset of 5 proxies from seven locations across the Yucatan Peninsula, to be compared with temperature and precipitation output from the Community Climate System Model Version 4 (CCSM4), which is part of the Coupled Model Intercomparison Project Phase 5 (CMIP5) past1000 experiment. The proxy dataset includes oxygen isotopes from speleothems and gastropod/ostrocod shells (11 records); and sediment density, mineralogy, and magnetic susceptibility records from lake sediment cores (3 records). The proxy dataset is supplemented by a compilation of reconstructed temperatures using pollen and tree ring records for North America (archived in the PAGES2k global network data). Our preliminary analysis suggests that many of these datasets show evidence of drier and warmer climate on the Yucatan Peninsula around the T.C.P. when compared to modern conditions, although the amplitude and timing of individual warming and drying events varies between sites. This comparison with modeled output will ultimately be used to inform backward shift factors that will be input to a stochastic weather generator. These shift factors will be based on monthly changes in temperature and precipitation and applied to a modern daily climate time series for the Yucatan Peninsula to produce a daily climate time series for the T.C.P.

  16. Quantitative distribution and functional groups of intertidal macrofaunal assemblages in Fildes Peninsula, King George Island, South Shetland Islands, Southern Ocean.

    PubMed

    Liu, Xiaoshou; Wang, Lu; Li, Shuai; Huo, Yuanzi; He, Peimin; Zhang, Zhinan

    2015-10-15

    To evaluate spatial distribution pattern of intertidal macrofauna, quantitative investigation was performed in January to February, 2013 around Fildes Peninsula, King George Island, South Shetland Islands. A total of 34 species were identified, which were dominated by Mollusca, Annelida and Arthropoda. CLUSTER analysis showed that macrofaunal assemblages at sand-bottom sites belonged to one group, which was dominated by Lumbricillus sp. and Kidderia subquadrata. Macrofaunal assemblages at gravel-bottom sites were divided into three groups while Nacella concinna was the dominant species at most sites. The highest values of biomass and Shannon-Wiener diversity index were found in gravel sediment and the highest value of abundance was in sand sediment of eastern coast. In terms of functional group, detritivorous and planktophagous groups had the highest values of abundance and biomass, respectively. Correlation analysis showed that macrofaunal abundance and biomass had significant positive correlations with contents of sediment chlorophyll a, phaeophorbide and organic matter. PMID:26233302

  17. Holocene deglacial history of the northeast Antarctic Peninsula - A review and new chronological constraints

    NASA Astrophysics Data System (ADS)

    Johnson, Joanne S.; Bentley, Michael J.; Roberts, Stephen J.; Binnie, Steven A.; Freeman, Stewart P. H. T.

    2011-12-01

    The northeast Antarctic Peninsula (NEAP) region is currently showing signs of significant environmental change, evidenced by acceleration of glacial retreat and collapse of both Larsen-A and -B ice shelves within the past 15 years. However, data on the past extent of the eastern margin of the Antarctic Peninsula Ice Sheet (APIS) and its Holocene retreat history are sparse, and hence we cannot yet put the recent changes into a long-term context. In order to investigate the timing of deglaciation, we present 16 new cosmogenic 10Be surface exposure ages from sites on northern James Ross Island (Cape Lachman, Johnson Mesa and Terrapin Hill) and Seymour Island. The majority of the ages cluster around 6-10 ka, with three significantly older (25-31 ka). We combine these ages with existing terrestrial and marine radiocarbon deglaciation ages, and a compilation of existing swath bathymetry data, to quantify the temporal and spatial character of the regional glacial history. Ice had begun to retreat from the outer shelf by 18.3 ka, reaching Seymour Island by ˜8 ka. Northern James Ross Island began to deglaciate around the time of the Early Holocene Climatic Optimum (c. 11-9.5 ka). Deglaciation continued, and a transition from grounded to floating ice in Prince Gustav Channel occurred around 8 ka, separating the James Ross Island ice cap from the APIS. This occurred shortly before Prince Gustav Channel ice shelf began to disintegrate at 6.2 ka. Our results suggest there may be a bathymetric control on the spatial pattern of deglaciation in the NEAP.

  18. Subglacial morphology and glacial evolution of the Palmer deep outlet system, Antarctic Peninsula

    NASA Astrophysics Data System (ADS)

    Domack, Eugene; Amblàs, David; Gilbert, Robert; Brachfeld, Stefanie; Camerlenghi, Angelo; Rebesco, Michele; Canals, Miquel; Urgeles, Roger

    2006-04-01

    The Palmer Deep is an erosional, inner-shelf trough located at the convergence of ice flow from three distinct accumulation centers. It served as a funnel for ice flow out across the continental shelf of the Antarctic Peninsula. Swath mapping of 1440 km 2 of seafloor in and adjacent to the Palmer Deep basin defines a large paleo-ice stream that flowed 230 km across the Antarctic Peninsula continental shelf during the Last Glacial Maximum (MIS-2). The unique perspective and detail of the Palmer Deep physiography allow us to recognize several phases of erosion and deposition in the outlet basin. These events are uniquely constrained by two ODP drill cores (sites 1099 and 1098) that together recovered over 150 m of latest Pleistocene and Holocene sediment. We divide this region of the continental shelf into three zones based upon mega- to meso-scale bathymetric features and emphasize that all three were part of one glacial outlet during the most recent period of glaciation. These zones include from inner shelf to outer shelf: the Palmer Deep basin, the Palmer Deep Outlet Sill and the Hugo Island Trough. Specific seafloor features associated with these zones include: relict terraces, sub-glacial lake deltas, channels and levees, debris slopes, spindle and out bed forms, mega-scale glacial lineations, morainal banks, and bank breach points. The origin of many of these features can be linked to the development of a sub-glacial lake basin within the Palmer Deep during or prior to MIS-2, its subsequent drainage, and recession of the Palmer Deep ice stream system. This sub-glacial lake system is reconstructed at the head of a major paleo-ice stream.

  19. Variability on the Hypoxic Conditions in the Northwestern Region of the Baja California Peninsula

    NASA Astrophysics Data System (ADS)

    Bustos-Serrano, H.

    2015-12-01

    The NW region of the Baja California peninsula in México is dominated by the California Current System (CCS). Dissolved oxygen (DO) is a key variable in water bodies because it is considered as a health in biological processes. Hypoxic conditions (DO 60 to 120 μmol kg-1) occur naturally in large areas of the ocean. In the Eastern Pacific, the DO can be altered by eutrophication, derived from anthropogenic activity, especially in shallow and enclosed seas. Fluctuations in the conditions of hypoxia zones may have significant ecological and economic impact. It is of interest in assessing whether hypoxic conditions in the vicinity of Bahia de Todos Santos (BTS) and Coronado Islands in México are altered by anthropogenic activity (Figs. 1 and 2 respectively). For the present study, we worked with data collected from oceanographic expeditions during the period October 2010 to June 2015. The DO was determined using a CTD (SBE Model 25) and by sea water collection with hydrographic bottles using a modification of the Winkler method. The signs of hypoxia are evident in the area near BTS and in the vicinity of Coronado´s Islands, mainly on locations between the Todos Santos Islands and the peninsula of Punta Banda, which shows that the hypoxic zone begins to occur in shallow water between 50-200 m depth. This particular area corresponds to the point where the Mexican Navy determined as a site for dredging materials from the ports of Ensenada and El Sauzal, it is possible that the anthropogenic activity alters the natural conditions of hypoxia in the area to enlarge. In June 2012 for the first time in that region we obtained sediment samples below 700 m depth, which are mixed terrigenous clastic and oceanic sediments.

  20. Soil-landform-plant communities relationships of a periglacial landscape at Potter Peninsula, Maritime Antarctica

    NASA Astrophysics Data System (ADS)

    Poelking, E. L.; Schaefer, C. E. R.; Fernandes Filho, E. I.; de Andrade, A. M.; Spielmann, A. A.

    2014-08-01

    Integrated studies on the interplay between soils, periglacial geomorphology and plant communities are crucial for the understanding of climate change effects on terrestrial ecosystems of Maritime Antarctica, one of the most sensitive areas to global warming. Knowledge on physical environmental factors that influence plant communities can greatly benefit studies on monitoring climate change in Maritime Antarctica, where new ice-free areas are being constantly exposed, allowing plant growth and organic carbon inputs. The relationship between topography, plant communities and soils was investigated in Potter Peninsula, King George Island, Maritime Antarctica. We mapped the occurrence and distribution of plant communities and identified soil-landform-vegetation relationships. The vegetation map was obtained by classification of a Quickbird image, coupled with detailed landform and characterization of 18 soil profiles. The sub-formations were identified and classified, and we also determined the total elemental composition of lichens, mosses and grasses. Plant communities at Potter Peninsula occupy 23% of the ice-free area, at different landscape positions, showing decreasing diversity and biomass from the coastal zone to inland areas where sub-desert conditions prevail. There is a clear dependency between landform and vegetated soils. Soils with greater moisture or poorly drained, and acid to neutral pH, are favourable for mosses subformations. Saline, organic-matter rich ornithogenic soils of former penguin rookeries have greater biomass and diversity, with mixed associations of mosses and grasses, while stable felseenmeers and flat rocky cryoplanation surfaces are the preferred sites for Usnea and Himantormia lugubris lichens, at the highest surface. Lichens subformations cover the largest vegetated area, showing varying associations with mosses.

  1. Soil-landform-plant-community relationships of a periglacial landscape on Potter Peninsula, maritime Antarctica

    NASA Astrophysics Data System (ADS)

    Poelking, E. L.; Schaefer, C. E. R.; Fernandes Filho, E. I.; de Andrade, A. M.; Spielmann, A. A.

    2015-05-01

    Integrated studies on the interplay between soils, periglacial geomorphology and plant communities are crucial for the understanding of climate change effects on terrestrial ecosystems of maritime Antarctica, one of the most sensitive areas to global warming. Knowledge on physical environmental factors that influence plant communities can greatly benefit studies on the monitoring of climate change in maritime Antarctica, where new ice-free areas are being constantly exposed, allowing plant growth and organic carbon inputs. The relationship between topography, plant communities and soils was investigated on Potter Peninsula, King George Island, maritime Antarctica. We mapped the occurrence and distribution of plant communities and identified soil-landform-vegetation relationships. The vegetation map was obtained by classification of a QuickBird image, coupled with detailed landform and characterization of 18 soil profiles. The sub-formations were identified and classified, and we also determined the total elemental composition of lichens, mosses and grasses. Plant communities on Potter Peninsula occupy 23% of the ice-free area, at different landscape positions, showing decreasing diversity and biomass from the coastal zone to inland areas where sub-desert conditions prevail. There is a clear dependency between landform and vegetated soils. Soils that have greater moisture or are poorly drained, and with acid to neutral pH, are favourable for moss sub-formations. Saline, organic-matter-rich ornithogenic soils of former penguin rookeries have greater biomass and diversity, with mixed associations of mosses and grasses, while stable felsenmeers and flat rocky cryoplanation surfaces are the preferred sites for Usnea and Himantormia lugubris lichens at the highest surface. Lichens sub-formations cover the largest vegetated area, showing varying associations with mosses.

  2. Meteorological hazard assessment based on trends and abrupt changes in rainfall characteristics on the Korean peninsula

    NASA Astrophysics Data System (ADS)

    Sung, Jang Hyun; Chung, Eun-Sung; Kim, Yeonjoo; Lee, Bo-Ram

    2015-09-01

    This study presents a statistical approach for assessing meteorological hazards based on trends and abrupt changes in precipitation characteristics. Daily rainfall data from 64 stations in South Korea (SK) and 27 stations in North Korea (NK) were used to identify temporal patterns in the rainfall characteristics of both regions using seven rainfall indices, such as the total annual rainfall and annual number of wet days. This study suggests the use of three steps in identifying meteorological hazards based on two statistical analyses. In step 1, we conducted a trend analysis of a 10-year moving average of the rainfall index using the Mann-Kendall (MK) trend test. Most stations (65.6 %) in SK exhibit clear increasing trends in five indices, whereas far fewer have data indicating any trends in five of the indices in NK (25.9 %). In step 2, abrupt changes in all rainfall indices were identified using a Bayesian Change Point (BCP) approach. The results contradict those from the MK trend analysis. The proportion of stations in NK where trends were identified is much higher than that in SK. In step 3, the results from the two previous steps were integrated to identify the meteorological hazards based on the identified trend and change point. The BCP approach can be used to identify meteorological hazards that MK cannot, as the former approach focuses on the change point during the entire period. As a result, meteorological stability at the sites of weather stations can be identified, and then the meteorological hazards across the entire Korean peninsula can be spatially interpolated. Although SK and NK are located on the same peninsula, distinct differences in the trends were observed.

  3. Forest response to increasing typhoon activity on the Korean peninsula: evidence from oak tree-rings.

    PubMed

    Altman, Jan; Doležal, Jiří; Cerný, Tomáš; Song, Jong-Suk

    2013-02-01

    The globally observed trend of changing intensity of tropical cyclones over the past few decades emphasizes the need for a better understanding of the effects of such disturbance events in natural and inhabited areas. On the Korean Peninsula, typhoon intensity has increased over the past 100 years as evidenced by instrumental data recorded from 1904 until present. We examined how the increase in three weather characteristics (maximum hourly and daily precipitation, and maximum wind speed) during the typhoon activity affected old-growth oak forests. Quercus mongolica is a dominant species in the Korean mountains and the growth releases from 220 individuals from three sites along a latitudinal gradient (33-38°N) of decreasing typhoon activity were studied. Growth releases indicate tree-stand disturbance and improved light conditions for surviving trees. The trends in release events corresponded to spatiotemporal gradients in maximum wind speed and precipitation. A high positive correlation was found between the maximum values of typhoon characteristics and the proportion of trees showing release. A higher proportion of disturbed trees was found in the middle and southern parts of the Korean peninsula where typhoons are most intense. This shows that the releases are associated with typhoons and also indicates the differential impact of typhoons on the forests. Finally, we present a record of the changing proportion of trees showing release based on tree-rings for the period 1770-1979. The reconstruction revealed no trend during the period 1770-1879, while the rate of forest disturbances increased rapidly from 1880 to 1979. Our results suggest that if typhoon intensity rises, as is projected by some climatic models, the number of forest disturbance events will increase thus altering the disturbance regime and ecosystem processes. PMID:23504787

  4. Dust Optical Properties Over North Africa and Arabian Peninsula Derived from the AERONET Dataset

    NASA Technical Reports Server (NTRS)

    Kim, D.; Chin, M.; Yu, H.; Eck, T. F.; Sinyuk, A.; Smirnov, A.; Holben, B. N.

    2011-01-01

    Dust optical properties over North Africa and the Arabian Peninsula are extracted from the quality assured multi-year datasets obtained at 14 sites of the Aerosol Robotic Network (AERONET). We select the data with (a) large aerosol optical depth (AOD >= 0.4 at 440 nm) and (b) small Angstrom exponent (A(sub ext)<= 0.2) for retaining high accuracy and reducing interference of non-dust aerosols. The result indicates that the major fraction of high aerosol optical depth days are dominated by dust over these sites even though it varies depending on location and time. We have found that the annual mean and standard deviation of single scattering albedo, asymmetry parameter, real refractive index, and imaginary refractive index for Saharan and Arabian desert dust is 0.944 +/- 0.005, 0.752 +/- 0.014, 1.498 +/- 0.032, and 0.0024 +/- 0.0034 at 550 nm wavelength, respectively. Dust aerosol selected by this method is less absorbing than the previously reported values over these sites. The weaker absorption of dust from this study is consistent with the studies using remote sensing techniques from satellite. These results can help to constrain uncertainties in estimating global dust shortwave radiative forcing.

  5. Channel initiation by groundwater sapping in Kanozan, Boso Peninsula of central Japan

    NASA Astrophysics Data System (ADS)

    Matsushi, Y.; Hattanji, T.

    2006-12-01

    Groundwater sapping is known as one of the important processes for channel initiation. We examined hydro- geomorphic factors that affect channel initiation by groundwater sapping. The study site (Mt. Kanozan) is located in Boso Peninsula, 50-km southeast of Tokyo, central Japan. Unconfined sandstone with high permeability comprises the mountain. Some features of piping, boiling and seepage erosion were found along first and second-order channels. Runoff at a spring site (SS) kept a constant discharge throughout year, and did not show any responses to typhoon storms with over 100-mm total rainfall. We surveyed micro-topography of 12 channel heads. Most channel heads have steep head slope (35-45 deg.) and gentle gradient downstream (5-10 deg.). Gentle slope of groundwater table immediately above channel head (roughly 7 deg. at the spring site SS) controls channel gradient, and affects distinct gradient transition at channel heads. We could not found any significant correlation between source area and local slope at channel heads, probably due to a scattered relation between surface drainage area and spring discharge. All channel heads are located in an altitude zone of 50-100 m, while the altitude of mountain peak is 270 m. The limited altitude distribution of channel heads implies that channel initiation of this area should be controlled by a critical altitude associated with deep groundwater flow systems.

  6. Self-similarity patterns of precipitation in the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Morata, A.; Martín, M. L.; Luna, M. Y.; Valero, F.

    2006-05-01

    An objective classification of the precipitation field over the Iberian Peninsula and the Balearic Islands is obtained. Data are derived from a high-resolution daily precipitation dataset obtained from in-situ measurements. The dataset, Iberian monthly Precipitation Dataset (IPD), consists of monthly precipitation data over a 25 km × 25 km grid from 1st January 1961 to 31st December 2003. Therefore, 960 data series over the Iberian Peninsula and the Balearic Islands are disposed over the grid for 43-year period. Multi-resolution wavelet analysis is used to extract similar information in the precipitation field at different timescales. An objective classification of the obtained wavelet coefficient series is carried out by means of the Kohonen’s neural network, also named Self-Organizing Map (SOM). SOM is formed by an unsupervised learning algorithm that may be used to find clusters of similar events in the input data and is able to identify some underlying dynamic structures of the multi-dimensional datasets. SOM is applied to the wavelet coefficients for intramonthly, intermonthly and interannual oscillations, obtaining self-organised maps which objectively identify similar zones of precipitation behaviour over the Iberian Peninsula. The homogeneity of the patterns is also studied by means of non-parametric correlations, energy scalograms and tests of significance. The intramonthly, intermonthly and interannual waves resulted in seven, five and three SOM patterns, respectively. As timescale increases, the wavelet series coefficients tend to be highly clustered. The results indicate that as the oscillation frequencies decrease, the Iberian precipitation behaves more linearly.

  7. Cenozoic evolution of the Antarctic Peninsula continental margin

    SciTech Connect

    Anderson, J.B. )

    1990-05-01

    Cenozoic evolution of the Antarctic Peninsula continental margin has involved a series of ridge (Aluk Ridge)-trench collisions between the Pacific and Antarctic plates. Subduction occurred episodically between segments of the Pacific plate that are bounded by major fracture zones. The age of ridge-trench collisions decreases from south to north along the margin. The very northern part of the margin, between the Hero and Shackleton fracture zones, has the last surviving Aluk-Antarctic spreading ridge segments and the only remaining trench topography. The sedimentary cover on the northern margin is relatively thin generally less than 1.5 km, thus providing a unique setting in which to examine margin evolution using high resolution seismic methods. Over 5,000 km of high resolution (water gun) seismic profiles were acquired from the Antarctic Peninsula margin during four cruises to the region. The margin is divided into discrete fracture-zone-bounded segments; each segment displays different styles of development. Highly tectonized active margin sequences have been buried beneath a seaward-thickening sediment wedge that represents the passive stage of margin development Ice caps, which have existed in the Antarctic Peninsula region since at least the late Oligocene, have advanced onto the continental shelf on numerous occasions, eroding hundreds of meters into the shelf and depositing a thick sequence of deposits characterized by till tongues and glacial troughs. Glacial erosion has been the main factor responsible for overdeepening of the shelf; isostasy is of secondary importance. As the shelf was lowered by glacial erosion, it was able to accommodate thicker and more unstable marine ice sheets. The shelf also became a vast reservoir for cold, saline shelf water, one of the key ingredients of Antarctic bottom water.

  8. Scaling Tendency of Geothermal Waters Armutlu Peninsula, Northwestern Turkey

    NASA Astrophysics Data System (ADS)

    Ertekin, Can

    2015-04-01

    Prediction of scaling tendencies from geothermal waters is important for taking necessary precautions to prevent or control the scale formation. This study contains scaling tendency of geothermal outlets occurring through Armutlu Peninsula in Northwestern Turkey. The E-W trending region stretches into the Marmara Sea (ca. 117 km E-W by 45 km N-S) and is bounded to the north and the south by North Anatolian Fault Zone (NAFZ). The two branches of NAFZ traversing the peninsula control not only active seismicity but also geothermal discharges of the region. Widespread basement rocks across the peninsula including metamorphic assemblage of granitic and volcanic rocks host geothermal fluids. The two distinctive geothermal discharges (Armutlu and Yalova) take place through lineaments appurtenant to the northern branch of NAFZ. Their discharge temperatures of 65 ° C (Yalova) and 70 ° C (Armutlu) are the highest of the region. According to their water chemical results, scaling tendency were computed by using WATCH for different temperature steps under the assumptions of single-stage adiabatic boiling and equilibrium degassing. To evaluate their scaling tendencies, mean geothermal reservoir temperatures were computed by using chemical geothermometers. Scaling tendencies were plotted for calcite, amorphous silica and quartz minerals for different temperature values including reservoir temperatures. Their scaling behavior reveals that oversaturation with calcite and quartz minerals are rapidly attained for the geothermal fluids (Yalova and Armutlu) at relatively lower temperatures. Regarding amorphous silica, they are completely undersaturated. Besides, Langelier Saturation Index (LSI) and Ryznar Stability Index (RSI) were calculated. Their results depict scale formation due to being positive LSI and less than 6.0 of RSI values.

  9. Changing structures and dynamics of western Antarctic Peninsula Ice Shelves

    NASA Astrophysics Data System (ADS)

    Glasser, N. F.; Holt, T. O.; Quincey, D. J.; Fricker, H.; Siegfried, M. R.

    2013-12-01

    Over the last three decades, Antarctic Peninsula Ice Shelves have shown a pattern of sustained retreat, often ending in catastrophic and rapid breakup. This study provides a detailed analysis of the structures and dynamics of three western Antarctic Peninsula ice shelves: Bach, Stange and George VI Ice Shelves. Spatial extent and glaciological surface features were mapped for each ice shelf from 1973 to 2010 using optical and radar satellite images to assess their structural evolution, historical dynamics and stability. InSAR and feature-tracking methods were used to assess the recent dynamic configurations of the ice shelves from 1989 to 2010. Repeat ICESat measurements were used to evaluate their vertical changes from 2003 to 2008. On Bach Ice Shelf, the formation of two large fractures near the ice front is linked to widespread thinning (~2 ma-1) and sustained retreat (~360 km2). It looks likely that iceberg calving along these fractures will alter the frontal geometry sufficiently to promote enhanced, irreversible retreat within the next decade. On George VI Ice Shelf, acceleration is observed at both ice fronts; linked to a release of back-stresses through continued ice loss (1995 km2 in total). The most significant changes are recorded at its southern ice front, with ice flow accelerating up to 360% between ca. 1989 and ca. 2010, coupled with widespread rifting and a mean thinning rate of 2.1 ma-1. On Stange Ice Shelf, shear-induced fracturing was observed between two flow units, also linked to widespread thinning (~4.2 ma-1). A semi-quantitative assessment reveals that the southern margin of George VI Ice Shelf is most susceptible to rapid retreat, whilst its northern ice front, Bach Ice Shelf and the northern front of Stange Ice Shelf are more vulnerable than those situated on the east Antarctic Peninsula.

  10. Lichens of Izembek National Wildlife Refuge, westernmost Alaska Peninsula

    USGS Publications Warehouse

    Talbot, S. S.; Talbot, S.L.; Thomson, J.W.; Schofield, W.B.

    2000-01-01

    One hundred eighty-two taxa of lichens including two lichen parasites are reported from Izembek National Wildlife Refuge on the tip of the Alaska Peninsula. Metasphaeria tartarina is new to North America; Scoliciosporum umbrinum is new to Alaska. Wide-ranging, arctic-alpine, and boreal species dominate the lichen flora; a coastal element is moderately represented, while amphi-Beringian species form a minor element. Epigeic lichen abundance is described along a lowland to alpine mesotopographic gradient selected to represent major landscape variation in the refuge. Of six major community types identified, three had significant lichen components.

  11. SeaWiFS Images Fires on Yucatan Peninsula

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image from the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) shows dense smoke from fires in the Yucatan peninsula on April 24, 2000. In the El Nino year of 1998 fires in the region emitted enough smoke to cause authorities in Texas to issue air quality warnings. For more information, see: SeaWiFS Project Home Page Global Fire Monitoring 4km2 TRMM Fire Data Image provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  12. Late Cenozoic stress field distribution in Biga Peninsula, NW Turkey

    NASA Astrophysics Data System (ADS)

    Ozden, S.; Bekler, T.; Tutkun, S. Z.; Kurcer, A.; Ates, O.; Bekler, F. N.; Kalafat, D.

    2009-04-01

    Biga Peninsula is a seismically active region both in instrumental and historical period in NW Turkey. In this part, middle and southern branches of North Anatolian Fault are represented by Etili, Can-Biga, Yenice-Gonen, Manyas-Danisment, Lapseki, Sinekci, Terzialan, Dogruca, Uluabat, Edincik, Pazarkoy-Hamdibey-Kalkim, Edremit, Yigitler, Sarikoy-Inova, Troia and Karabiga Faults. All of these faults are responsible of the seismic activity in Biga Peninsula. Historical earthquakes happened in 29, 155, 170, 543, 620, 1440, 1737, 1855, 1865 and 1875. Furthermore, as for instrumental period, Saros Gulf-Murefte earthquakes (M:7.3 and M:6.3) in 1912, Erdek Gulf (M:6.4) and Can-Biga (M:6.3) in 1935, Edremit Gulf-Ayvaci k (M:6.8) in 1944, Yenice-Gonen (M:7.2) in 1953, Gonen (M:5.8) in 1964, Edremit-Baki rcay (M:5.5) in 1971, Biga (M:5.8) in 1983, Kusgolu-Manyas (M:5.2) and Bandirma (M:5.0) in 2006. In this study, we determined the Late Cenozoic stress field distribution and present-day tectonic regimes both fault-slip data (by 253 fault planes) and earthquake focal mechanism solutions (by 58 earthquakes) were investigated by the inversion methods. The results indicate that a transtensional stress regime is dominant with a NW-SE to WNW-ESE directed compression (1) and NE-SW to ENE-WSW directed extension (3), which yielded a NE-SW, ENE-WSW and also E-W trending strike-slip faulting faults with a normal component. While a transtensional tectonic regime has an active component in Biga Peninsula, a local and consistent transpressional tectonic regime were determined along an E-W trending narrow zone in the northern part of the Biga Peninsula also. The tectonic regime and stress field is resulted from interactions both continental collision of Eurasian/Anatolian/Arabian plate in the east and subduction processes (roll back and/or slab-pull) of the African plate along the Cyprus and Hellenic arc in the Mediterranean region.

  13. Potential Effects of Climate Change on the Distribution of Cold-Tolerant Evergreen Broadleaved Woody Plants in the Korean Peninsula.

    PubMed

    Koo, Kyung Ah; Kong, Woo-Seok; Nibbelink, Nathan P; Hopkinson, Charles S; Lee, Joon Ho

    2015-01-01

    Climate change has caused shifts in species' ranges and extinctions of high-latitude and altitude species. Most cold-tolerant evergreen broadleaved woody plants (shortened to cold-evergreens below) are rare species occurring in a few sites in the alpine and subalpine zones in the Korean Peninsula. The aim of this research is to 1) identify climate factors controlling the range of cold-evergreens in the Korean Peninsula; and 2) predict the climate change effects on the range of cold-evergreens. We used multimodel inference based on combinations of climate variables to develop distribution models of cold-evergreens at a physiognomic-level. Presence/absence data of 12 species at 204 sites and 6 climatic factors, selected from among 23 candidate variables, were used for modeling. Model uncertainty was estimated by mapping a total variance calculated by adding the weighted average of within-model variation to the between-model variation. The range of cold-evergreens and model performance were validated by true skill statistics, the receiver operating characteristic curve and the kappa statistic. Climate change effects on the cold-evergreens were predicted according to the RCP 4.5 and RCP 8.5 scenarios. Multimodel inference approach excellently projected the spatial distribution of cold-evergreens (AUC = 0.95, kappa = 0.62 and TSS = 0.77). Temperature was a dominant factor in model-average estimates, while precipitation was minor. The climatic suitability increased from the southwest, lowland areas, to the northeast, high mountains. The range of cold-evergreens declined under climate change. Mountain-tops in the south and most of the area in the north remained suitable in 2050 and 2070 under the RCP 4.5 projection and 2050 under the RCP 8.5 projection. Only high-elevations in the northeastern Peninsula remained suitable under the RCP 8.5 projection. A northward and upper-elevational range shift indicates change in species composition at the alpine and subalpine

  14. Potential Effects of Climate Change on the Distribution of Cold-Tolerant Evergreen Broadleaved Woody Plants in the Korean Peninsula

    PubMed Central

    Koo, Kyung Ah; Kong, Woo-Seok; Nibbelink, Nathan P.; Hopkinson, Charles S.; Lee, Joon Ho

    2015-01-01

    Climate change has caused shifts in species’ ranges and extinctions of high-latitude and altitude species. Most cold-tolerant evergreen broadleaved woody plants (shortened to cold-evergreens below) are rare species occurring in a few sites in the alpine and subalpine zones in the Korean Peninsula. The aim of this research is to 1) identify climate factors controlling the range of cold-evergreens in the Korean Peninsula; and 2) predict the climate change effects on the range of cold-evergreens. We used multimodel inference based on combinations of climate variables to develop distribution models of cold-evergreens at a physiognomic-level. Presence/absence data of 12 species at 204 sites and 6 climatic factors, selected from among 23 candidate variables, were used for modeling. Model uncertainty was estimated by mapping a total variance calculated by adding the weighted average of within-model variation to the between-model variation. The range of cold-evergreens and model performance were validated by true skill statistics, the receiver operating characteristic curve and the kappa statistic. Climate change effects on the cold-evergreens were predicted according to the RCP 4.5 and RCP 8.5 scenarios. Multimodel inference approach excellently projected the spatial distribution of cold-evergreens (AUC = 0.95, kappa = 0.62 and TSS = 0.77). Temperature was a dominant factor in model-average estimates, while precipitation was minor. The climatic suitability increased from the southwest, lowland areas, to the northeast, high mountains. The range of cold-evergreens declined under climate change. Mountain-tops in the south and most of the area in the north remained suitable in 2050 and 2070 under the RCP 4.5 projection and 2050 under the RCP 8.5 projection. Only high-elevations in the northeastern Peninsula remained suitable under the RCP 8.5 projection. A northward and upper-elevational range shift indicates change in species composition at the alpine and subalpine

  15. Monitoring of Landslides using Repeated Kinematics GPS Observables in Sevketiye Town, Biga Peninsula, Çanakkale, NW Turkey

    NASA Astrophysics Data System (ADS)

    Cuneyt Erenoglu, Ramazan; Akcay, Ozgun; Karaca, Zeki; Erenoglu, Oya; Sengul Uluocak, Ebru; Yucel, Mehmet Ali

    2014-05-01

    Landslide is one of the most important natural events, and is also a result of earth's crust movements. Landslides generally result in the outward and downward movement of slope-forming materials consisting soil, rock, artificial fill and etc. Moreover, possible earthquakes are one of the main reasons of triggering landslides in active areas seismically. There have been many studies based on the Global Positioning System (GPS) observables to compute the three dimensional positioning of established sites, and to model landslides precisely. We can monitor landslide with GPS using continuous data collection or the type of campaign surveying. While continuous data collection provide a millimetre-level of accuracy, the accuracy decreases with the shorter sessions, e.g. campaign surveying, due to possible sources of error. The area, located west of the Çanakkale, has been studied to identify the landslide susceptibility and geology. Çanakkale, NW Turkey, is located on the territory of the Biga Peninsula and the Gallipoli Peninsula. The section of remaining at the west of the line from the Gulf of Edremit to the Gulf of Erdek is called Biga Peninsula, and it covers an area of approximately 10 thousand km². In the Biga Peninsula, the main morphological units are at the western, northern and southern of coastal plains, and on their behind the hills, plateaus and mountainous areas of the inland. But at the middle areas, it is often possible to find the tectonic depressions sandwiched between the masses plateau and mountainous. In general, moving down the slope of a rock, soil or debris can be defined as landslides that are ranks second in terms of caused losses after earthquakes in Turkey. Landslides, harm to urbanization as well as loss of lives and economic losses. Moreover they adversely affects to agricultural, forest areas and the quality of the rivers. For example, the gas pipeline connecting Turkey and Greece, which will provide gas to the Southern Europe passes

  16. Phylogenetic analysis of the complete mitochondrial genome of the Korean field mouse Apodemus peninsulae (Rodentia, Murinae) from China.

    PubMed

    Jeon, Mi Gyung; Kim, Ji Young; Park, Yung Chul

    2016-07-01

    We sequenced and characterized a complete mitogenome (KP671850) of the Chinese Apodemus peninsulae and compared it with a previously published mitogenome of the Korean A. peninsulae (NC016060). The total length of the Chinese A. peninsulae mitogenome is 16,457 bp. The mitogenome consists of 13 protein-coding genes (PCGs), two rRNA (12S rRNA and 16S rRNA) genes, 22 tRNA genes, and one D-loop region. The most common start codon was ATG, used in the nine PCGs for initiation. The mitogenomes of Chinese and Korean A. peninsulae showed 98.9% sequence similarity. The intra-/interspecific phylogeny of the Chinese A. peninsulae revealed that the Chinese A. peninsulae was well grouped with the Korean A. peninsulae. The clade of A. peninsulae was sister to that of Apodemus agrarius, Apodemus chejuensis, and Apodemus chevrieri. PMID:26006285

  17. ABCGheritage project - promoting geotourism in northern Finland, northern Norway and the Kola Peninsula

    NASA Astrophysics Data System (ADS)

    Pihlaja, Jouni; Johansson, Peter; Lauri, Laura S.

    2014-05-01

    Nature tourism has been a growing business sector in the Barents area during the recent decades. With the purpose to develop nature tourism in a sustainable way, a cooperation project ABCGheritage - Arctic Biological, Cultural and Geological Heritage has been carried out. Project has received partial funding from the EU Kolarctic ENPI program. In the geoheritage part of the project the main activities were aimed to develop pro-environmental ways of geotourism in the area. The three main participants in the geoheritage part of the project are the Geological Survey of Finland, Northern Finland Office, the Geological Institute of the Kola Science Centre of the Russian Academy of Sciences and Bioforsk Soil and Environment from northeastern Norway. The duration of the project is 2012-2014 and most of the work has already been completed even if most of the results are not published yet. Totally ten different tasks have been implemented in the geological part of the project. The largest task has been the preparation of a geological outdoor map and guide book of the Khibiny Tundra locating in the central part of the Kola Peninsula. In Finland already 11 such maps have been published, and the experiences gained during their production have been used in this project, too. Geological heritage trails to the Khibiny Tundra have also been created and they will be drawn on the map. The second concrete result is the Barents Tour for Geotourist -guide, which will be published as a guide book, web pages and an exhibition. The route comprises ca 35 best geological demonstration sites along the circle route from northern Finland to northeastern Norway, from there to Kola Peninsula and then back to Finland. Information of the route will be available for all interested travelers. In addition to the geological outdoor map of the Khibiny Tundra and "Barents Tour for Geotourists"-guide, the primary outputs of the project are the geological nature trails on the field, geological

  18. Nutrient transfers in ditches draining heavily manured soils of the Delmarva Peninsula

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drainage ditches are a ubiquitous feature of the Delmarva Peninsula, which abuts the Chesapeake Bay and is home each year to 600 million broiler poultry. Improved drainage is critical to human habitation, travel and industry on the Delmarva Peninsula where low-lying, flat topography is dappled with...

  19. 75 FR 16094 - Upper Peninsula Power Company; North American Hydro Holdings, LLC; Notice of Application for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-31

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Upper Peninsula Power Company; North American Hydro Holdings, LLC; Notice of Application for Transfer of License, and Soliciting Comments and Motions To Intervene March 24, 2010. On March 17, 2010, Upper Peninsula...

  20. 46 CFR 7.170 - Alaska Peninsula, AK to Aleutian Islands, AK.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Alaska Peninsula, AK to Aleutian Islands, AK. 7.170... BOUNDARY LINES Alaska § 7.170 Alaska Peninsula, AK to Aleutian Islands, AK. (a) A line drawn from the southernmost extremity of Cape Kumlium to the westernmost extremity of Nakchamik Island; thence to...

  1. 46 CFR 7.170 - Alaska Peninsula, AK to Aleutian Islands, AK.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Alaska Peninsula, AK to Aleutian Islands, AK. 7.170... BOUNDARY LINES Alaska § 7.170 Alaska Peninsula, AK to Aleutian Islands, AK. (a) A line drawn from the southernmost extremity of Cape Kumlium to the westernmost extremity of Nakchamik Island; thence to...

  2. 46 CFR 7.170 - Alaska Peninsula, AK to Aleutian Islands, AK.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Alaska Peninsula, AK to Aleutian Islands, AK. 7.170... BOUNDARY LINES Alaska § 7.170 Alaska Peninsula, AK to Aleutian Islands, AK. (a) A line drawn from the southernmost extremity of Cape Kumlium to the westernmost extremity of Nakchamik Island; thence to...

  3. 46 CFR 7.170 - Alaska Peninsula, AK to Aleutian Islands, AK.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Alaska Peninsula, AK to Aleutian Islands, AK. 7.170... BOUNDARY LINES Alaska § 7.170 Alaska Peninsula, AK to Aleutian Islands, AK. (a) A line drawn from the southernmost extremity of Cape Kumlium to the westernmost extremity of Nakchamik Island; thence to...

  4. 46 CFR 7.170 - Alaska Peninsula, AK to Aleutian Islands, AK.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Alaska Peninsula, AK to Aleutian Islands, AK. 7.170... BOUNDARY LINES Alaska § 7.170 Alaska Peninsula, AK to Aleutian Islands, AK. (a) A line drawn from the southernmost extremity of Cape Kumlium to the westernmost extremity of Nakchamik Island; thence to...

  5. Mission and modern citrus species diversity of Baja California Peninsula cases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spring-fed mission oases of the Baja California peninsula, Mexico, hold several species, varieties and unique hybrids of heritage citrus, which may represent valuable genetic resources. Citrus species first arrived to the peninsula with the Jesuit missionaries (1697-1768), and new varieties were...

  6. 77 FR 64330 - Upper Peninsula Power Company; Notice of Application Accepted for Filing, Soliciting Motions To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Upper Peninsula Power Company; Notice of Application Accepted for Filing.... d. Applicant: Upper Peninsula Power Company. e. Name of Project: Bond Falls Hydroelectric Project....

  7. Transboundary transport and deposition of Hg emission from springtime biomass burning in the Indo-China Peninsula

    NASA Astrophysics Data System (ADS)

    Wang, Xun; Zhang, Hui; Lin, Che-Jen; Fu, Xuewu; Zhang, Yiping; Feng, Xinbin

    2015-09-01

    Biomass burning from the Indo-China Peninsula region is an important source of atmospheric mercury (Hg). We isolated 18 unique transport events over 2 years using observations of Hg and CO at a high-altitude background site in southwestern China (Mount Ailao Observatory Station) to assess the transport and impact of Hg emissions from biomass burning. The quantity of Hg emission and the source regions were determined using ΔTGM/ΔCO slopes coupled with backward trajectory analysis and CO emission inventories. The slopes of ΔTGM/ΔCO appeared to be a useful chemical indicator for source identification. Industrial emission sources exhibited slopes in the range of 5.1-61.0 × 10-7 (parts per trillion by volume, pptv/pptv), in contrast to a slope of 2.0-6.0 × 10-7 for typical biomass burning. Transboundary transport of Hg from biomass burning led to episodically elevated atmospheric Hg concentrations during springtime. Hg emissions from biomass burning in the Indo-China Peninsula region from 2001 to 2008 were estimated to be 11.4 ± 2.1 Mg yr-1, equivalent to 40% of annual anthropogenic emissions in the region. In addition, Hg emissions from biomass burning contained a substantial fraction of particulate bound Hg (PBM). Assuming that PBM readily deposits locally (within 50 km), the local Hg deposition caused by the PBM was estimated to be 2.2 ± 0.4 Mg yr-1, up to 1 order of magnitude higher than the PBM deposition caused by anthropogenic emissions during springtime in the region. The strong springtime emissions potentially pose a threat to the ecosystems of the Indo-China Peninsula and southwest China.

  8. Mantle-Lid P Wave Attenuation in the Korean Peninsula

    NASA Astrophysics Data System (ADS)

    Lee, K.; Hong, T.

    2012-12-01

    The mantle-lid P wave, Pn, is the first arrival phase in regional distances. The Pn waves are widely analyzed for estimation of event sizes. Also, it is known that analysis of Pn waves is effective for discrimination of nuclear explosions from natural earthquakes. The attenuation of Pn waves provides us information on medium properties in mantle lid. It is crucial to understand the nature of Pn attenuation for correct estimation of event sizes from Pn amplitudes. We investigate the lateral variation of Pn attenuation in the mantle lid of the Korean Peninsula from vertical regional seismograms for events around the Korean Peninsula and Japanese islands. The number of events is 149, and the focal depths are less than 50 km. The seismic records with signal-to-noise ratios greater than 1.5 are analyzed. The number of stations is 121. The Pn quality factors are calculated using a two-station method in which ratios of Pn displacement spectra of stations on the same azimuths are used. The power-law frequency dependence term is estimated using a least-squares fitting for quality factors at frequencies from 0.37 Hz to 25 Hz. The number of station pairs is 3317. The average quality factor at 1 Hz is determined to be about 67, which is consistent with previous studies. We present the resultant Pn attenuation model, and discuss the correlations with geological and geophysical properties in the medium.

  9. Magnetotelluric measurements on the Methana Peninsula (Greece): modelling and interpretation

    NASA Astrophysics Data System (ADS)

    Volti, Theodora K.

    1999-01-01

    As a first deep geophysical survey, thirteen magnetotelluric and magnetovariation soundings in the period range of 0.0085-6000 s have been carried out in the Methana Peninsula and Trizina area (Greece), which form the western part of the active Hellenic Volcanic Arc. Data have been processed using robust techniques and further analysed using decomposition methods in order to find the regional azimuth. By using the smooth inverse of Smith and Booker (J. Geophys. Res. 96, 3905-3922, 1991), the 2-D modelling has resolved a low-resistivity area (<30 Ω m) at depths of 2-3 km beneath the volcanics, whereas elsewhere the resistivity is much higher (>100 Ω m). Parkinson induction arrows also at the range 0.01-0.1 s point towards the centre of the peninsula. The conductivity anomaly is interpreted as being connected with the volcanic history of Methana, as a cooler remnant of former magmatic activity. The contrast with the much higher resistivities suggested at depths >5 km, is discussed in terms of fluid mobility, limitation of the MT method and extensional processes in the southern Aegean.

  10. Neogene paleoenvironments and tectonics of the Hongchun Peninsula, southern Taiwan

    SciTech Connect

    Chang, S. . Taiwan Petroleum Exploration Div.); Vondra, C.F. . Geological Atmospheric Sciences)

    1993-03-01

    Recent investigations in the Hongchun Peninsula in southern Taiwan provide new evidence concerning the paleoenvironmental and tectonic interpretation of the structurally complex Neogene sediments exposed there. The deposits of the peninsula have been divided into four distinct fault-bounded sequences each displaying a different lithology and style of structural development. The Mutanchi formation consists of feldspathic quartz arenites derived from a granitic provenance to the north that were deposited in a forearc basin. The lower part of the Mutanchi is dominated by thick proximal turbidities and interbedded highly contorted shales of submarine fan origin. These grade upward into shallow marine feldpathic quartz arenites and shales. The Shiman Formation consists of tuffaceous lithic arenites (proximal turbidities) and diamicites (debris flow deposits) with gravel-sized metamorphic and volcanic clasts in the lower part and interbedded lithic arenites and shales in the upper part. Although of contrasting lithology to the Mutanchi, the lower part of the Shiman Formation was also deposited on a submarine fan in a forearc tectonic setting while the upper part was deposited on a shallow marine shelf. The Kentin Formation is composed entirely of thick light green mudstones with contorted slump structures. Locally it contains very large exotic blocks (olistoliths) of variable lithology and is interpreted to be a melange -- the Kentin Melange. The above four fault-bounded units represent a forearc basin-accretionary wedge complex that developed during the late Neogene as a result of convergent interaction between the South China and Philippine plates.

  11. Cirques upon the Kamchatka Peninsula: palaeoglacial and palaeoclimatic inferences

    NASA Astrophysics Data System (ADS)

    Barr, Iestyn; Spagnolo, Matteo

    2013-04-01

    The morphometry of more than 3,500 cirques upon the Kamchatka Peninsula, Eastern Russia, has been analysed. Volumetric analysis suggests that these cirques have developed rather isometrically—growing equally in all dimensions. The cirques show a very strong N bias in their azimuth, likely resulting from aspect-related variations in insolation. The strength of this N bias is considered to indicate that former glaciation was often 'marginal', and mainly of cirque-type. This assertion is supported by the fact that S and SE-facing cirques are the highest in the dataset, suggesting that glacier-cover was rarely sufficient to allow S and SE-facing glaciers to develop at low altitudes. The strength of these azimuth-related variations in cirque altitude is thought to reflect comparatively cloud-free conditions during former periods of glaciation. These characteristics, of marginal glaciation and comparatively cloud-free conditions, are considered to reflect the region's former aridity, at the global Last Glacial Maximum, and during earlier periods of ice advance. There is published evidence to suggest extensive glaciation of the Kamchatka Peninsula at times during the Late Quaternary, yet the cirque data appears to suggest that such phases were comparatively short-lived, and that smaller cirque-type glaciers were generally more characteristic of the period.

  12. Regional ocean tide loading modelling around the Iberian Peninsula

    NASA Astrophysics Data System (ADS)

    Benavent, M.; Arnoso, J.; Montesinos, F. G.

    2009-12-01

    We developed a new 1/12° resolution oceanic tide model in the complex region that surrounds the Iberian Peninsula. The model, named IBER01, allows us to obtain more accurate tidal loading computations for precise geodetic and gravimetric observations in this area. The modelling follows the scheme of data assimilation (coastal tide gauge, bottom pressure sensors and TOPEX/Poseidon altimetry) into a hydrodynamical model, which is based on two-dimensional barotropic depth averaged shallow-water equations. Detailed bathymetry data and quadratic bottom friction with a specific drag coefficient for the region have been considered. Improved ocean load maps for the Iberian Peninsula are obtained for eight harmonic constituents (Q1, P1, O1, K1, N2, M2, S2 and K2), after computing the load effect (Newtonian attraction and elastic contribution) using IBER01 and six present-day global oceanic tide models for comparison. The results achieved verify the quality of the new model. Our ocean loading computations reduce considerably the discrepancies between the theoretical Earth tide parameters and those from observations at the level of 0.3%.

  13. Beryllium deposits of the western Seward Peninsula, Alaska

    USGS Publications Warehouse

    Sainsbury, C.L.

    1963-01-01

    Deposits of beryllium ore in the Lost River area of the western Seward Peninsula, Alaska, consist of replacement veins, pipes, and stringer lodes is limestone in a zone about 7 miles long and 2 to 3 miles wide which is faulted and intruded by dikes and stocks. The ores are remarkably alike and typically consist of the following minerals, in percent: fluorite, 45-65; diaspore, 5-10; tourmaline, 0-10; chrysoberyl, 3-10; white mica, 0-5; small amounts of hematite, sulfide minerals, manganese oxide, other beryllium minerals; and traces of minerals not yet identified. The ores generally are cut by late veinlets which are of the same mineralogy as the groundmass ore, or which consist of fluorite, white mica, and euclase. The ores are fine grained, and many of the individual mineral grains, except fluorite, are less than 1 mm in size. The beryllium content of bulk samples of ore ranges from 0.11 to 0.54 percent (0.31 to 1.50 percent BeO). High-grade nodules, composed principally of chrysoberyl, diaspore, fluorite, and mica, contain as much as 6 percent BeO. Geochemical reconnaissance has disclosed other areas of anomalous beryllium in stream sediments elsewhere on the Seward Peninsula, generally around biotite granites that have them associated with tin deposits; additional exploration probably will disclose other deposits.

  14. Alaskan Peninsula Cenozoic stratigraphy: stratigraphic sequences and current research

    SciTech Connect

    Allison, R.C.; Armentrout, J.M.

    1985-04-01

    Geology of the Alaska Peninsula-Island Arc and Continental Margin, by C.A. Burk, is the principal reference for stratigraphic studies on the Alaska Peninsula. Burk mapped the Phanerozoic stratigraphy and provided a geologic history and structural interpretation of the area between Wide Bay and Unimak Island. Cenozoic rocks were mapped as three unconformity-bounded sequences. Recognition of specific formations was difficult due to similarity of lithofacies, isolated outcrops, rapid facies changes, and alteration and burial by young volcanics. Consequently, megafossil assemblages were relied upon to facilitate correlations between study areas. The three unconformity-bounded Cenozoic sequences are: (1) the Paleogene Beaver Bay Group consisting of three formations: the dominantly nonmarine Tolstoi Formation, the dominantly marine Stepovak Formation, and the volcanic Meshik Formation. Current work suggests these units are at least in part coeval facies of late Paleocene through Oligocene age. (2) The Neogene Bear Lake Formation consisting of the lower Unga Conglomerate Member and an unnamed upper member. Rapid facies changes and incorrect reports of fossil occurrence have resulted in confusion of stratigraphic relationships within this sequence of middle to late Miocene age. (3) A late Neogene informally defined upper sequence consisting of interbedded marginal marine, coastal-plain, and volcanic facies. Current work suggests this sequence is Pliocene through Pleistocene in age.

  15. Modeling dynamics of tundra plant communities on the Yamal Peninsula, Russia

    NASA Astrophysics Data System (ADS)

    Yu, Q.; Epstein, H. E.; Walker, D. A.

    2010-12-01

    Multiple environmental drivers, including climate, soil conditions and herbivory, affect arctic tundra vegetation dynamics. These factors may have been evaluated individually in the past; however, their interactions contribute to more complicated tundra plant community dynamics and may represent a substantial source of uncertainty in predicting tundra ecosystem properties in the changing Arctic. This study investigates the effects of soils, grazing, and climate change on tundra plant communities at the plant functional type (PFT) level, based on previous integrated modeling research at the ecosystem level. The study area encompasses the Yamal Peninsula, northwestern Siberia, where soil and biomass data were collected along the Yamal Arctic Transect (YAT), to drive a nutrient-based tundra vegetation model (ArcVeg) and to validate the simulation results. We analyzed plant functional type biomass and net primary productivity (NPP), and found that with higher temperatures (+2°C mean growing season temperature), most plant functional types responded positively with increased biomass and NPP, while grazing suppressed such responses in both high and low soil organic nitrogen (SON) sites. The magnitudes of the responses to warming depended on SON and grazing intensity. Relatively, there were greater responses of biomass and NPP in low SON sites compared to high SON sites. Moss biomass (in contrast to other plant types) declined 34% with warming in the low SON site and 28% in the high SON site in subzone E (the most southern tundra subzone). Increases in Low Arctic shrub biomass with warming were 61% in the high SON site in subzone E and 96% in the low SON site. Decrease in moss biomass due to warming was mitigated about 2% by high grazing frequency (maximum of 25% of biomass removal every two years) in the high SON site in subzone E, with an opposite effect in the low SON site. High grazing frequency caused greater relative increases in total shrub biomass for both low

  16. What shapes edaphic communities in mineral and ornithogenic soils of Cierva Point, Antarctic Peninsula?

    NASA Astrophysics Data System (ADS)

    Mataloni, G.; Garraza, G. González; Bölter, M.; Convey, P.; Fermani, P.

    2010-08-01

    Three mineral soil and four ornithogenic soil sites were sampled during summer 2006 at Cierva Point (Antarctic Peninsula) to study their bacterial, microalgal and faunal communities in relation to abiotic and biotic features. Soil moisture, pH, conductivity, organic matter and nutrient contents were consistently lower and more homogeneous in mineral soils. Ornithogenic soils supported larger and more variable bacterial abundances than mineral ones. Algal communities from mineral soils were more diverse than those from ornithogenic soils, although chlorophyll- a concentrations were significantly higher in the latter. This parameter and bacterial abundance were correlated with nutrient and organic matter contents. The meiofauna obtained from mineral soils was homogeneous, with one nematode species dominating all samples. The fauna of ornithogenic soils varied widely in composition and abundance. Tardigrades and rotifers dominated the meiofauna at eutrophic O2, where they supported a large population of the predatory nematode Coomansus gerlachei. At site O3, high bacterial abundance was consistent with high densities of the bacterivorous nematodes Plectus spp. This study provides evidence that Antarctic soils are complex and diverse systems, and suggests that biotic interactions (e.g. competition and predation) may have a stronger and more direct influence on community variability in space and time than previously thought.

  17. Vertical Methane Migration on the Hikurangi Margin off the Mahia Peninsula, New Zealand

    NASA Astrophysics Data System (ADS)

    Coffin, R. B.; Rose, P. S.; Yoza, B.; Boyd, T. J.; Crutchley, G. J.; Mountjoy, J. J.; Pecher, I. A.

    2015-12-01

    This study focuses on gas source and vertical migration patterns in sediments on the Hikurangi Margin, east of the North Island, New Zealand off the Mahia Peninsula, collected aboard the RV Tangaroa (TAN1508) during June 2015. Seismic and Topas data collected on board were used to organize a coring plan for this expedition. Selection of piston core locations was based on spatial variation in vertical gas migration across seismic patterns indicating BSR migration toward the sediment surface. Higher molecular weight gases were not observed at this location suggesting a biogenic gas source. Across this transect, methane concentrations varied by more than an order of magnitude at stations within a few hundred meters. The highest methane concentrations were 5051.7 ppm in Core 004 at and 2413.4 ppm in Core 036. Concentrations at other sites ranged from 23.8 to 125.9 ppm. Methane concentrations showed a strong correlation with seismic and Topas data that suggested high vertical migration and large shallow gas pockets. While these data focused on locations across a BSR, higher methane concentrations, ranging from 1529 to 7862 ppm were observed in three cores from a nearby site where a BSR was not observed. This presentation will compare spatial variation in the vertical gas migration and stable isotopic composition of sediment organic and inorganic carbon, methane and porewater dissolved inorganic carbon among the core locations to better understand vertical methane migration and shallow sediment methane cycling.

  18. Assessing trace element contamination in Fildes Peninsula (King George Island) and Ardley Island, Antarctic.

    PubMed

    Amaro, Eduardo; Padeiro, Ana; Mão de Ferro, André; Mota, Ana Maria; Leppe, Marcelo; Verkulich, Sergey; Hughes, Kevin A; Peter, Hans-Ulrich; Canário, João

    2015-08-15

    King George Island, situated in the South Shetland Islands archipelago, is one of the most visited sites in Antarctica. This has contributed to a high density of scientific stations and shelters in the region, especially in Fildes Peninsula. In order to evaluate the natural and anthropogenic sources of trace elements (As, Cd, Cu, Zn, Pb and Hg) soil and moss samples were collected from different sites in January 2013. In general, the results revealed homogeneous concentrations (μgg(-)(1)) for each element in the majority of collected samples (As: 3.8±1.4; Cd: 0.4±0.9; Cu: 34±4; Zn: 115±13; Pb: 20±5; Hg; 0.011±0.009). However, some samples in specific areas of Fildes Bay showed the existence of local anthropogenic activities that have contributed to the enrichment of contaminants in soils and moss samples that correlated to one another (e.g. Pb: 1101μgg(-)(1)). Human presence is linked to examples of contamination and environmental perturbation, making essential the implementation of this type of study in order to understand and protect unique places in Antarctica. PMID:25982820

  19. An analysis of historical Mussel Watch Programme data from the west coast of the Cape Peninsula, Cape Town.

    PubMed

    Sparks, Conrad; Odendaal, James; Snyman, Reinette

    2014-10-15

    The concentrations of metals in the mussel Mytilus galloprovincialis (Lamarck, 1819) prevalent along the west coast of the Cape Peninsula, Cape Town are presented. The mussels were sampled during the routine "Mussel Watch Programme" (MWP) between 1985 and 2008. Levels of Cu, Cd, Pb, Zn, Hg, Fe and Mn at Cape Point, Hout Bay, Sea Point, Milnerton and Bloubergstrand were analysed for autumn and spring and showed consistent similar mean values for the five sites. There was a highly significant temporal (annual and seasonal) difference between all metals as well as a significant difference in metal concentrations between the five sites. The concentrations of Zn, Fe, Cd and Pb were higher than previous investigations and possibly indicative of anthropogenic sources of metals. The results provide a strong motivation to increase efforts in marine pollution research in the area. PMID:25127737

  20. Simulating the effects of soil organic nitrogen and grazing on arctic tundra vegetation dynamics on the Yamal Peninsula, Russia

    NASA Astrophysics Data System (ADS)

    Yu, Qin; Epstein, Howard; Walker, Donald

    2009-10-01

    Sustainability of tundra vegetation under changing climate on the Yamal Peninsula, northwestern Siberia, home to the world's largest area of reindeer husbandry, is of crucial importance to the local native community. An integrated investigation is needed for better understanding of the effects of soils, climate change and grazing on tundra vegetation in the Yamal region. In this study we applied a nutrient-based plant community model—ArcVeg—to evaluate how two factors (soil organic nitrogen (SON) levels and grazing) interact to affect tundra responses to climate warming across a latitudinal climatic gradient on the Yamal Peninsula. Model simulations were driven by field-collected soil data and expected grazing patterns along the Yamal Arctic Transect (YAT), within bioclimate subzones C (high arctic), D (northern low arctic) and E (southern low arctic). Plant biomass and NPP (net primary productivity) were significantly increased with warmer bioclimate subzones, greater soil nutrient levels and temporal climate warming, while they declined with higher grazing frequency. Temporal climate warming of 2 °C caused an increase of 665 g m-2 in total biomass at the high SON site in subzone E, but only 298 g m-2 at the low SON site. When grazing frequency was also increased, total biomass increased by only 369 g m-2 at the high SON site in contrast to 184 g m-2 at the low SON site in subzone E. Our results suggest that high SON can support greater plant biomass and plant responses to climate warming, while low SON and grazing may limit plant response to climate change. In addition to the first order factors (SON, bioclimate subzones, grazing and temporal climate warming), interactions among these significantly affect plant biomass and productivity in the arctic tundra and should not be ignored in regional scale studies.

  1. Multichannel Seismic Investigations of Sediment Drifts off West Antarctica and the Antarctic Peninsula: Preliminary Results from Research Cruise JR298

    NASA Astrophysics Data System (ADS)

    Larter, R. D.; Graham, A. G. C.; Hernandez-Molina, J.; Channell, J. E. T.; Hillenbrand, C. D.; Hogan, K. A.; Uenzelmann-Neben, G.; Gohl, K.; Rebesco, M.; Hodell, D. A.

    2015-12-01

    The West Antarctic Ice Sheet (WAIS) and Antarctic Peninsula Ice Sheet (APIS) have exhibited significant changes over recent decades but there is still great uncertainty about how rapidly and how far they will retreat in a warmer climate. For example, it remains unclear whether or not the marine-based WAIS "collapsed" during the last interglacial period, resulting in a global sea-level rise contribution of more than 3 m. Previous studies, including Ocean Drilling Program (ODP) Leg 178, have shown that sediment drifts on the continental rise west of the Antarctic Peninsula contain a rich high-resolution archive of Antarctic margin paleoceanography and APIS history that extends back to at least the Late Miocene. The potential of existing ODP cores from the drifts is, however, compromised by the fact that composite sections are incomplete and lack of precise chronological control. A new drilling proposal (732-Full2) has been scientifically approved and is with the JOIDES Resolution Facilities Board of the International Ocean Discovery Program for scheduling. The main aims of the proposal are to obtain continuous, high-resolution records from sites on sediment drifts off both the Antarctic Peninsula and West Antarctica (southern Bellingshausen Sea) and to achieve good chronological control on them using a range of techniques. We present preliminary results from a recent site survey investigation cruise on RRS James Clark Ross (JR298) that obtained high-resolution multichannel seismic reflection data over the proposed sites and adjacent working areas. The new data provide a basis for interpretation of (i) sedimentary processes that operated during the development of the drifts, and (ii) links between depositional systems on the continental rise, paleo-ice-sheet dynamics and paleoceanographic processes. Through further analyses of seismic and other geophysical data, in combination with marine sediment cores retrieved from the proposed sites, we aim to provide insight into

  2. Expanding Ice Sheets on the Antarctic Peninsula during the Plio/Pleistocene Recorded in Continental Rise Sediment Drifts

    NASA Astrophysics Data System (ADS)

    Cowan, E. A.; Hillenbrand, C.

    2007-12-01

    Sediment drifts on the continental rise west of the Antarctic Peninsula are located within 125 km from the continental shelf edge, the main contributor of terrigenous sediment during both glacial and interglacial periods. The composition of drift deposits continuously recorded changes in ice sheet volume and thermal regime as well as sea surface temperatures (SSTs) and sea ice extent. The coarse-grained terrigenous sediment (pebbles and coarse sand), a proxy for iceberg-rafted debris (IRD), was analyzed in sediments spanning the last 3.1 m.y. at Ocean Drilling Program (ODP) Sites 1101 and 1096. IRD is deposited in both glacial intervals, dominated by fine-grained laminated mud and interglacial units consisting of bioturbated muds enriched in biogenic components. Contents of biogenic opal, which reflect diatom abundance, are relatively high from 3.1-2.2 Ma. Calcareous nannofossils are present within interglacial sediments from 2.2-0.76 Ma. Both findings suggest warm SSTs and limited sea ice over the drifts during interglacial periods before the Late Pleistocene. Quartz grains picked from the IRD fraction and imaged with a scanning electron microscope (SEM) show an abrupt change in surface microtextures at 1.35 Ma. During the Late Pliocene to Early Pleistocene, many quartz grains are completely weathered and only a few show signs of crushing and abrasion, indicating that glaciers were too small to inundate the Antarctic Peninsula topography. Debris shed from mountain peaks was transported supraglacially or englacially allowing weathered grains to pass unmodified through the glaciers. Glaciers expanded in size during glacial periods from 1.35-0.76 Ma. The IRD accumulation during those periods was very high and diverse dropstone lithologies document supply from sources throughout the Antarctica Peninsula. Conditions that spawned the large polar ice sheet identified at the Last Glacial Maximum have been present on the Antarctic Peninsula during glacial periods since

  3. Segmentation of Hypocenters and 3-D Velocity Structure around the Kii Peninsula Revealed by Onshore and Offshore Seismic Observations

    NASA Astrophysics Data System (ADS)

    Akuhara, T.; Mochizuki, K.; Nakahigashi, K.; Yamada, T.; Shinohara, M.; Sakai, S.; Kanazawa, T.; Uehira, K.; Shimizu, H.

    2013-12-01

    The Philippine Sea Plate subducts beneath the Eurasian Plate at a rate of ~4 cm/year along the Nankai Trough, southwest of Japan. Around the Kii Peninsula, the rupture boundary of the historical Tonankai and Nankai large earthquakes is located, and previous researches have revealed along-strike segmentation of hypocenters [Mochizuki et al., 2010], P-wave anisotropy [Ishise et al., 2009], low frequency earthquake (LFE) distribution [e.g., Obara, 2010] and subduction depth of the Philippine Sea (PHS) Plate, or there may exist a split in the PHS Plate [Ide et al., 2010]. To investigate such segmentation, in our previous work we determined 3-D velocity structure and hypocenters using P- and S-wave arrival times of earthquakes recorded by both ocean bottom seismometers (OBSs) that were deployed from 2003 to 2007 and on-land stations [Akuhara et al., 2013]. As a result, it was discovered that Vp/Vs ratio is also segmented within the oceanic crust and at the bottom of the overriding plate, which coincides with the LFE distribution: segment A is located along the Kii Channel, segment B around the western Kii Peninsula, and segment C around the eastern Kii Peninsula. In segment B, Vp/Vs ratio is low within the oceanic crust and LFE cluster characterized by an anomalously small amount of cumulative slip, compared to the other LFE clusters around the Kii Peninsula, is located [Obara, 2010]. The difference of Vp/Vs ratio and LFE activity among segments were interpreted as difference of pore fluid pressure. In fact, similar segmentation can be seen in hypocenters: Segment A with concentrated seismicity in the oceanic mantle, segment B with that in the oceanic crust, and segment C with little seismicity. To derive characteristic patterns of the hypocenters, we conducted a cluster analysis of earthquakes based on waveform similarity represented by cross-correlation coefficients (CCs) [e.g., Cattaneo, 1999], in which we took varying structural site effects among the OBS stations

  4. Current Status and Future Directives of the Nicoya Peninsula Continuous GPS Network, Costa Rica, In Regard to Slip Style and Distribution

    NASA Astrophysics Data System (ADS)

    Psencik, K. C.; Jiang, Y.; Lafemina, P. C.; Dixon, T. H.; Protti, M.; Gonzalez, V.; Sklar, J.; Blume, F.

    2007-12-01

    The close proximity of the Nicoya Peninsula land mass to the Cocos-Caribbean subduction zone plate boundary makes it a prime location to use GPS to study such plate boundary processes as locking zone dynamics and episodic tremor and slip events. Nicoya Peninsula currently has 12 continuous GPS (CGPS) stations installed each with varying degrees of equipment and communication. Seven of these sites are currently installed with Trimble NetRS receivers and five with Trimble 5700 receivers. Of these 12 sites, four are equipped with SIM cards and modems for direct download capabilities, one of which is connected to a router for direct internet access. This site, LIMO, located in Limonal, is being monitored on the PBO network by UNAVCO with all of the quality and systems checks that this implies. The other eight sites currently require manual download. All sites with NetRS receivers are currently partitioned to record both 5Hz and 30 second position data. We will present the first years time series from these stations. The advantage to recording at a 5 Hz interval is that the receivers may be used to record long period dynamic events during large earthquakes along the Cocos-Caribbean plate boundary. One goal of the network is to investigate episodic tremor and slip events, as have been observed in the Cascadia subduction boundary. Such events have been speculated upon in this region, however due to the sparse network at that time, we were unable to resolve the event. With the expanded network of CGPS stations, we hope to better record and understand such events. We will also present an anlaysis of synthetic data to assess the spacial resolution of detectable slip patterns with the current network spacing. There is a future plan of three more installations on the interior of the peninsula to further optimize the network for seismic and locking pattern studies.

  5. Earthquake Swarm in Armutlu Peninsula, Eastern Marmara Region, Turkey

    NASA Astrophysics Data System (ADS)

    Yavuz, Evrim; Çaka, Deniz; Tunç, Berna; Serkan Irmak, T.; Woith, Heiko; Cesca, Simone; Lühr, Birger-Gottfried; Barış, Şerif

    2015-04-01

    The most active fault system of Turkey is North Anatolian Fault Zone and caused two large earthquakes in 1999. These two earthquakes affected the eastern Marmara region destructively. Unbroken part of the North Anatolian Fault Zone crosses north of Armutlu Peninsula on east-west direction. This branch has been also located quite close to Istanbul known as a megacity with its high population, economic and social aspects. A new cluster of microseismic activity occurred in the direct vicinity southeastern of the Yalova Termal area. Activity started on August 2, 2014 with a series of micro events, and then on August 3, 2014 a local magnitude is 4.1 event occurred, more than 1000 in the followed until August 31, 2014. Thus we call this tentatively a swarm-like activity. Therefore, investigation of the micro-earthquake activity of the Armutlu Peninsula has become important to understand the relationship between the occurrence of micro-earthquakes and the tectonic structure of the region. For these reasons, Armutlu Network (ARNET), installed end of 2005 and equipped with currently 27 active seismic stations operating by Kocaeli University Earth and Space Sciences Research Center (ESSRC) and Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum (GFZ), is a very dense network tool able to record even micro-earthquakes in this region. In the 30 days period of August 02 to 31, 2014 Kandilli Observatory and Earthquake Research Institute (KOERI) announced 120 local earthquakes ranging magnitudes between 0.7 and 4.1, but ARNET provided more than 1000 earthquakes for analyzes at the same time period. In this study, earthquakes of the swarm area and vicinity regions determined by ARNET were investigated. The focal mechanism of the August 03, 2014 22:22:42 (GMT) earthquake with local magnitude (Ml) 4.0 is obtained by the moment tensor solution. According to the solution, it discriminates a normal faulting with dextral component. The obtained focal mechanism solution is

  6. The return to the Iberian Peninsula: first Quaternary record of Muscardinus and a palaeogeographical overview of the genus in Europe

    NASA Astrophysics Data System (ADS)

    Garcia-Ibaibarriaga, Naroa; Arrizabalaga, Álvaro; Iriarte-Chiapusso, María-José; Rofes, Juan; Murelaga, Xabier

    2015-07-01

    Although the earliest record of the genus Muscardinus dates from the Middle Miocene in Spain, no mention has been reported since the Lower Pliocene in the Iberian Peninsula. In this paper, Quaternary fossil remains of a hazel dormouse (Muscardinus avellanarius) are described, for the first time, in the Iberian Peninsula. These remains constitute the south-westernmost record of the genus in the Eurasian continent during the Late Pleistocene. The fossils, one first upper molar (M1) and two second upper molars (M2), come from Lezetxiki II Cave, an early Late Pleistocene site in northern Spain. The presence of the hazel dormouse agrees with the abundance of rodent species indicative of woodland, suggesting mild climatic conditions and a landscape formed by deciduous forest. This assemblage has been arguably assigned to warm and humid conditions related to an interstadial period in MIS 5. We also present an overview of the palaeogeography of the genus in Europe. The identification of this dormouse reinforces the idea of biological corridors between western Iberia and the rest of Europe during the Pleistocene.

  7. Assessing Impacts of Disturbances and Climate Change on Carbon Stocks in Mexican Semidry Forests of the Yucatan Peninsula

    NASA Astrophysics Data System (ADS)

    Dai, Z.; Birdsey, R.; Johnson, K.; Dupuy, J. M.; Hernandez-Stefanoni, J. L.; Richardson, K.

    2014-12-01

    The spatially explicit biogeochemical model Forest-DNDC was used to estimate carbon dynamics with disturbances and climate change in secondary semidry forests in Yucatan Peninsula. The model was validated using observations from 276 field plots in a 350 km2 region of semi-deciduous forest surrounding the intensive monitoring site at Kaxil Kiuic, and it performed well with high performance efficiency (E=0.79, R2=0.83). The simulation results showed substantial spatial differences in biomass in the forests due to historical disturbance patterns and heterogeneous forest environments. The simulated impacts of the disturbances that occurred from 1998-2010 revealed an estimated loss of total biomass carbon storage of 154.7 Gg due mainly to about 12 km2 of forestland loss. The results from disturbance scenarios indicate that disastrous storms, which are not uncommon in the Yucatan Peninsula, can substantially impact carbon storage in a short time. However, warming can produce a long-term impact on carbon sequestration, due principally to the decrease in biomass carbon at a mean rate of over 100 kg ha-1yr-1 with an increase in temperature by 1 degree Celsius. The forests in this area are highly sensitive to warming due to a semidry climate where the evapotranspiration is higher than precipitation. Even if each degree of warming increase is accompanied by an increase in precipitation of 10%, the significant impact of warming cannot be dismissed.

  8. Impacts of Changing Permafrost Extent on Vegetation Transitions on the Seward Peninsula, Alaska

    NASA Astrophysics Data System (ADS)

    Lloyd, A. H.; Fastie, C. L.; Yoshikawa, K.; Hinzman, L. D.; Fraver, M.

    2002-12-01

    Permafrost is an important control over the distribution of major vegetation types in the low arctic, and temporal changes in permafrost extent may thus be tightly coupled to changes in plant community distribution. For example, spruce trees have become more widespread during the 20th century on the Seward Peninsula, but in permafrost-affected areas with low topographic relief spruce have invaded tundra only where permafrost has thawed. Two hypotheses may explain the apparent dependence of treeline advance on permafrost. First, increased soil temperature associated with thawing permafrost may enhance spruce success. Second, degradation of permafrost may increase soil drainage in areas with low topographic relief, and thus create more favorable conditions for spruce. We investigated these hypotheses at a thaw pond complex on the Seward Peninsula, comparing the relationships between soil properties (thaw depth, surface and subsurface soil moisture) and woody plant communities in three sites: within the partially drained basin of the thaw pond, along the thaw pond banks and on the flat tundra surface surrounding the thaw pond. White spruce (Picea glauca) occurred primarily on or within 10 m of the top of pond banks. Spruce have established there continuously since at least 1820, and are present in groves with densities > 1500 trees/ha. Since 1960, spruce have successfully established at lower densities (1,000 trees/ha) in tundra sites within 10 m of the top of the banks. We found no spruce > 20 m from the banks. Live spruce occur within the pond basin only on palsas, but several dead spruce were found in the basin itself. Shrub community structure also varied significantly among sites. Two relatively large-stature shrubs,Betula nana and Salix sp., were more abundant on banks than in other sites, and the height of the shrub canopy was > 50% greater on banks than in other sites. Late summer thaw depth did not differ significantly among the three site types, but soil

  9. Beachrock horizons of the Nicoya Peninsula, Costa Rica: Implications for coastal neotectonics and paleogeodesy

    NASA Astrophysics Data System (ADS)

    Marshall, J.; Osborn, S.; Morrish, S.; Barnhart, A.; Wenceslao, L.; Landeros, M.; Butcher, A.; Ritzinger, B.; Wellington, K.; Protti, M.; Spotila, J. A.

    2012-12-01

    Beachrock deposits are a common feature of tropical coastlines, formed by precipitation of carbonate cements (calcite or aragonite) within intergranular pore spaces of beach sediments. In this study, we employ geomorphic, petrographic, and hydrochemical analyses to evaluate the formation mechanism and neotectonic significance of uplifted Holocene beachrock horizons on the Nicoya Peninsula, Costa Rica. The Nicoya Peninsula forms a prominent forearc high along the southern Middle America convergent margin. This emergent coastal landmass overlies the seismogenic zone and is sensitive to vertical movements of the earthquake cycle. The last major rupture of the Nicoya megathrust (M7.7, 1950) produced up to 1.5 m of coseismic coastal uplift, followed by gradual interseismic subsidence that continues today. Net Quaternary emergence is recorded by uplifted Pleistocene marine terraces and Holocene shore deposits, including carbonate-cemented beachrock. Along the rocky macro-tidal coastline of the Nicoya Peninsula, beachrock deposits occur in tabular seaward-dipping horizons (5-15o) that are 0.1-0.5 m thick, 2-5 m wide, and extend laterally 10s to 100s of m along the beach. At some sites, multiple imbricate horizons step up the beach face beyond the high tide zone. Outcrops typically occur where coastal streams or wetlands provide abundant groundwater. Radiocarbon ages (25 samples, 12 field sites) range from 0.7-3.8 ka for deposits on the modern beach, and from 4.5-5.3 ka for deposits located up to 0.5 km inland. Petrographic analyses reveal compositional and textural diversity among constituent sand grains and interstitial carbonate cements. Sands consist primarily of sub-angular to sub-rounded marine shell and coral fragments mixed with lithic and mineral grains derived from local outcrops of Cretaceous oceanic basement rock (basalt, olivine, plagioclase, pyroxene, vein quartz, and radiolarian chert). Interstitial cements occur in two distinct forms: 1) acicular circum

  10. Evidence for temperate conditions along the Antarctic peninsula during the Early Tertiary

    SciTech Connect

    Zinsmeister, W.J.

    1985-01-01

    Several investigators based on deep sea glacial marine sediments from the southern oceans and volcanic sequences in West Antarctica have suggested extreme glacial conditions existed around Antarctica during the early Tertiary. Their data suggest ice sheets with ice shelves greater than those today were present on Antarctica by the late Eocene. If these data are correct, conditions during the Eocene along the Peninsula were similar to those that exist today. Late Eocene faunas and floras from Seymour Island indicate that conditions along the Peninsula were temperature. No paleontologic or geologic evidence have been obtained from Seymour Island (64/degree/18'S) to support the existence of glacial conditions along the northern part of the Peninsula during the early Tertiary. The presence of large quantities of fossil wood and plant debris in the upper Eocene sediments on Seymour Island indicates the presence of dense forests on the Peninsula during the Eocene. The discovery of marsupial and land birds remains on Seymour Island also indicate the presence of abundant terrestrial life on the Peninsula. The occurrence of an abundant marine life on Seymour Island supports the existence of temperate conditions along the Peninsula. Similarities of the Eocene faunas and floras with present day biotas from Tasmania, New Zealand and southern South America indicate that conditions along the Antarctic Peninsula during the late Eocene were comparable to present day mid latitudes of the southern hemisphere.