Segmented lateral dyke growth in a rifting event at Bárðarbunga volcanic system, Iceland.

PubMed

Sigmundsson, Freysteinn; Hooper, Andrew; Hreinsdóttir, Sigrún; Vogfjörd, Kristín S; Ófeigsson, Benedikt G; Heimisson, Elías Rafn; Dumont, Stéphanie; Parks, Michelle; Spaans, Karsten; Gudmundsson, Gunnar B; Drouin, Vincent; Árnadóttir, Thóra; Jónsdóttir, Kristín; Gudmundsson, Magnús T; Högnadóttir, Thórdís; Fridriksdóttir, Hildur María; Hensch, Martin; Einarsson, Páll; Magnússon, Eyjólfur; Samsonov, Sergey; Brandsdóttir, Bryndís; White, Robert S; Ágústsdóttir, Thorbjörg; Greenfield, Tim; Green, Robert G; Hjartardóttir, Ásta Rut; Pedersen, Rikke; Bennett, Richard A; Geirsson, Halldór; La Femina, Peter C; Björnsson, Helgi; Pálsson, Finnur; Sturkell, Erik; Bean, Christopher J; Möllhoff, Martin; Braiden, Aoife K; Eibl, Eva P S

2015-01-08

Crust at many divergent plate boundaries forms primarily by the injection of vertical sheet-like dykes, some tens of kilometres long. Previous models of rifting events indicate either lateral dyke growth away from a feeding source, with propagation rates decreasing as the dyke lengthens, or magma flowing vertically into dykes from an underlying source, with the role of topography on the evolution of lateral dykes not clear. Here we show how a recent segmented dyke intrusion in the Bárðarbunga volcanic system grew laterally for more than 45 kilometres at a variable rate, with topography influencing the direction of propagation. Barriers at the ends of each segment were overcome by the build-up of pressure in the dyke end; then a new segment formed and dyke lengthening temporarily peaked. The dyke evolution, which occurred primarily over 14 days, was revealed by propagating seismicity, ground deformation mapped by Global Positioning System (GPS), interferometric analysis of satellite radar images (InSAR), and graben formation. The strike of the dyke segments varies from an initially radial direction away from the Bárðarbunga caldera, towards alignment with that expected from regional stress at the distal end. A model minimizing the combined strain and gravitational potential energy explains the propagation path. Dyke opening and seismicity focused at the most distal segment at any given time, and were simultaneous with magma source deflation and slow collapse at the Bárðarbunga caldera, accompanied by a series of magnitude M > 5 earthquakes. Dyke growth was slowed down by an effusive fissure eruption near the end of the dyke. Lateral dyke growth with segment barrier breaking by pressure build-up in the dyke distal end explains how focused upwelling of magma under central volcanoes is effectively redistributed over long distances to create new upper crust at divergent plate boundaries.

Palaeomagnetism of the Palaeoproterozoic Boonadgin Dyke Suite, Yilgarn Craton: Possible connection with India

NASA Astrophysics Data System (ADS)

Liu, Y.; Li, Z. X.; Pisarevsky, S.; Kirscher, U.; Mitchell, R.; Stark, J. C.

2017-12-01

A palaeomagnetic study was carried out on the newly identified 1.9 Ga Boonadgin dyke swarm in the Yilgarn Craton, Western Australia. Ten dykes revealed a high-temperature characteristic remanent magnetisation (ChRM) with dual polarities, directing either SW shallow downward (4 sites) or NE shallow upward (6 sites). Our results reveal that the Yilgarn Craton was at an equatorial palaeolatitude at 1.9 Ga. Meanwhile, a paleopole from the ca. 1.9 Ga Dharwar dykes of South India, supported by a positive baked-contact test, puts India at a similar paleolatitude. The Boonadgin dyke swarm can be interpreted to represent an arm of a radiating dyke swarm that shared the same plume centre with coeval mafic dykes in the Dharwar and Bastar cratons of southern India. We therefore propose that the Western Australia Craton (WAC, consisting of the the Yilgarn and Pilbara cratons) and South India were connected at ca. 1.89 Ga.

Large Igneous Provinces, Their Giant Mafic Dyke Swarms, and Links to Metallogeny

NASA Astrophysics Data System (ADS)

Jowitt, S.; Ernst, R. E.

2017-12-01

The relationships between large igneous provinces (LIPs), their giant dyke swarms and differing metallogenic systems can be condensed into five distinct although partially overlapping classifications: (1) LIP magmas that directly generate mineral deposits such as orthomagmatic Ni-Cu-PGE sulfides. Many carbonatites (Nb, Ta REE deposits) and kimberlites (diamonds) are also often LIP related. On the other hand, LIP-related thermal pulses (from a mantle plume) can sometimes destroy diamond potential in the overlying lithosphere. A key locus for Ni-Cu-PGE mineralization is within a few hundred km of the plume center region and plume centers are best located using giant radiating dyke swarms. Dyke subswarms with chalcophile element depletions can also be tracked "upstream" toward the plume center to identify exploration targets. (2) LIP magmas that provide energy, fluids, and/or metals for ore types such as hydrothermal volcanogenic massive sulfide (VMS) and iron oxide-copper-gold (IOCG) deposits. Heat loss from the margins of dykes and sills can also generate local enrichments in key metals (e.g. Co) within the surrounding sedimentary rocks. (3) LIP rocks (particularly sills and dykes) can act barriers to fluid flow and/or as reaction zones that control mineralizing events, act as structural traps within hydrocarbon systems, and form impermeable barriers that control water flow and hence aquifer formation (4) surficial effects, such as the formation of Ni-Co laterites and Al bauxites from tropical weathering of LIP mafic-ultramafic rocks (including volcanics fed by radiating dykes as well as the dykes themselves). This category also includes LIP-related anoxia events that generate hydrocarbon source rocks; and (5) indirect links between LIPs and ore deposits, where continental breakup-related LIP events define a `barcode' record (usually dominated by dyke swarms) that can be used to correlate and reconstruct Precambrian supercontinents. This fifth classification type

Mangrove forest against dyke-break-induced tsunami on rapidly subsiding coasts

NASA Astrophysics Data System (ADS)

Takagi, Hiroshi; Mikami, Takahito; Fujii, Daisuke; Esteban, Miguel; Kurobe, Shota

2016-07-01

Thin coastal dykes typically found in developing countries may suddenly collapse due to rapid land subsidence, material ageing, sea-level rise, high wave attack, earthquakes, landslides, or a collision with vessels. Such a failure could trigger dam-break tsunami-type flooding, or "dyke-break-induced tsunami", a possibility which has so far been overlooked in the field of coastal disaster science and management. To analyse the potential consequences of one such flooding event caused by a dyke failure, a hydrodynamic model was constructed based on the authors' field surveys of a vulnerable coastal location in Jakarta, Indonesia. In a 2 m land subsidence scenario - which is expected to take place in the study area after only about 10-20 years - the model results show that the floodwaters rapidly rise to a height of nearly 3 m, resembling the flooding pattern of earthquake-induced tsunamis. The depth-velocity product criterion suggests that many of the narrow pedestrian paths behind the dyke could experience strong flows, which are far greater than the safe limits that would allow pedestrian evacuation. A couple of alternative scenarios were also considered to investigate how such flood impacts could be mitigated by creating a mangrove belt in front of the dyke as an additional safety measure. The dyke-break-induced tsunamis, which in many areas are far more likely than regular earthquake tsunamis, cannot be overlooked and thus should be considered in disaster management and urban planning along the coasts of many developing countries.

Has dyke development in the Vietnamese Mekong Delta shifted flood hazard downstream?

NASA Astrophysics Data System (ADS)

Van Khanh Triet, Nguyen; Viet Dung, Nguyen; Fujii, Hideto; Kummu, Matti; Merz, Bruno; Apel, Heiko

2017-08-01

In the Vietnamese part of the Mekong Delta (VMD) the areas with three rice crops per year have been expanded rapidly during the last 15 years. Paddy-rice cultivation during the flood season has been made possible by implementing high-dyke flood defenses and flood control structures. However, there are widespread claims that the high-dyke system has increased water levels in downstream areas. Our study aims at resolving this issue by attributing observed changes in flood characteristics to high-dyke construction and other possible causes. Maximum water levels and duration above the flood alarm level are analysed for gradual trends and step changes at different discharge gauges. Strong and robust increasing trends of peak water levels and duration downstream of the high-dyke areas are found with a step change in 2000/2001, i.e. immediately after the disastrous flood which initiated the high-dyke development. These changes are in contrast to the negative trends detected at stations upstream of the high-dyke areas. This spatially different behaviour of changes in flood characteristics seems to support the public claims. To separate the impact of the high-dyke development from the impact of the other drivers - i.e. changes in the flood hydrograph entering the Mekong Delta, and changes in the tidal dynamics - hydraulic model simulations of the two recent large flood events in 2000 and 2011 are performed. The hydraulic model is run for a set of scenarios whereas the different drivers are interchanged. The simulations reveal that for the central VMD an increase of 9-13 cm in flood peak and 15 days in duration can be attributed to high-dyke development. However, for this area the tidal dynamics have an even larger effect in the range of 19-32 cm. However, the relative contributions of the three drivers of change vary in space across the delta. In summary, our study confirms the claims that the high-dyke development has raised the flood hazard downstream. However, it is not

High Resolution Analysis of Dyke Tips and Segments, Using Drones

NASA Astrophysics Data System (ADS)

Dering, G.; Micklethwaite, S.; Cruden, A. R.

2016-12-01

We analyse outstanding exposures of dykes from both coastal (Western Australia) and high altitude glacier-polished (Sierra Nevada, California) outcrops, representing intrusion at shallow upper-crustal and mid-crustal conditions respectively. We covered 10,000 m^2 of outcrop area sampling the ground at a scale of 3-5 mm per pixel. Using Structure-from-Motion photogrammetry from ground-based and UAV photographs lacking GPS camera positions (>500 images per study), we generated and calibrated a 3D geometry of dense point clouds by selectively using 25-30 ground control points measured by high precision GPS (40-90 mm error). Ground control points used in the photogrammetric model building process typically yielded a root mean square error (RMSE) of 5 cm. Half the ground control points were withheld from the model building process and when they were compared against the model they yielded RMSE values only 6-10% higher than the points used for georeferencing, suggesting good internal consistency of the dataset and accuracy relative to the reference frame, at least for the purposes of this study. The structural orientations of the dykes and associated fractures were then extracted digitally using the iterative Random Sample Consensus method (RANSAC) and least-squares plane fitting. Furthermore, fracture intensity relative to dykes was measured along a series of scanlines and the running average and variance calculated. All results were compared against field measurements. Results show fracture intensity increases toward the dykes in the shallow crustal examples (West Australia) but no such fractures exist around the mid-crustal (Californian) dykes. Despite this there is a remarkable uniformity of geometry, and by implication process, between the two dyke sets. In order to extract full value from the big visual data now available to us, the near-future requires dedicated research into software solutions for expert-driven, semi-automatic mapping of geology and structure.

Engaging Karen Refugee Students in Science Learning through a Cross-Cultural Learning Community

ERIC Educational Resources Information Center

Harper, Susan G.

2017-01-01

This research explored how Karen (first-generation refugees from Burma) elementary students engaged with the Next Generation Science Standards (NGSS) practice of constructing scientific explanations based on evidence within the context of a cross-cultural learning community. In this action research, the researcher and a Karen parent served as…

Challenging dyke ascent models using novel laboratory experiments: Implications for reinterpreting evidence of magma ascent and volcanism

NASA Astrophysics Data System (ADS)

Kavanagh, Janine L.; Burns, Alec J.; Hilmi Hazim, Suraya; Wood, Elliot P.; Martin, Simon A.; Hignett, Sam; Dennis, David J. C.

2018-04-01

Volcanic eruptions are fed by plumbing systems that transport magma from its source to the surface, mostly fed by dykes. Here we present laboratory experiments that model dyke ascent to eruption using a tank filled with a crust analogue (gelatine, which is transparent and elastic) that is injected from below by a magma analogue (dyed water). This novel experimental setup allows, for the first time, the simultaneous measurement of fluid flow, sub-surface and surface deformation during dyke ascent. During injection, a penny-shaped fluid-filled crack is formed, intrudes, and traverses the gelatine slab vertically to then erupt at the surface. Polarised light shows the internal stress evolution as the dyke ascends, and an overhead laser scanner measures the surface elevation change in the lead-up to dyke eruption. Fluorescent passive-tracer particles that are illuminated by a laser sheet are monitored, and the intruding fluid's flow dynamics and gelatine's sub-surface strain evolution is measured using particle image velocimetry and digital image correlation, respectively. We identify 4 previously undescribed stages of dyke ascent. Stage 1, early dyke growth: the initial dyke grows from the source, and two fluid jets circulate as the penny-shaped crack is formed. Stage 2, pseudo-steady dyke growth: characterised by the development of a rapidly uprising, central, single pseudo-steady fluid jet, as the dyke grows equally in length and width, and the fluid down-wells at the dyke margin. Sub-surface host strain is localised at the head region and the tail of the dyke is largely static. Stage 3, pre-eruption unsteady dyke growth: an instability in the fluid flow appears as the central fluid jet meanders, the dyke tip accelerates towards the surface and the tail thins. Surface deformation is only detected in the immediate lead-up to eruption and is characterised by an overall topographic increase, with axis-symmetric topographic highs developed above the dyke tip. Stage 4 is

A Q & A with Karen Hughes

ERIC Educational Resources Information Center

Chronicle of Higher Education, 2007

2007-01-01

This article presents an excerpt from the interview of Karen Hughes, under secretary of state for public diplomacy and public affairs. Hughes discusses the Bush administration's effort to attract foreign students to the United States and to send American students overseas. She also talks about what American colleges and universities can do to help.

Dyke-path formation in relation to the eruptions of Eyjafjallajökull 2010 and Bardarbunga-Holuhraun 2014

NASA Astrophysics Data System (ADS)

Gudmundsson, Agust

2015-04-01

Dykes are extension fractures and form when the magmatic overpressure is high enough to rupture (break) the host rock. Their formation is entirely analogous to that of many joints and human-made hydraulic fractures, such as are used to increase permeability in reservoirs. When generating their paths, dykes use existing weaknesses (e.g., cooling joints) in the host rock. The maximum depth of large tension fractures below the surface of a rift zone, however, is mostly less than a few hundred metres. If the fractures extend to greater depths, they must change into closed normal faults which are generally not used as magma paths. There are thus no large tension fractures or wide-open faults at great depths ready to be filled with magma to form a dyke. While magma flow in dykes, as in other fluid-driven fractures, is at any point in various directions dyke segmentation may indicate the overall large-scale flow direction. Thus, dykes composed of large-spaced disconnected segments in lateral sections are primarily formed in vertical magma flow at segmentation depth whereas those composed of large-spaced disconnected segments in vertical sections are primarily formed in lateral magma flow. The far-field displacement and stress fields of segmented dykes are similar to those generated by single, continuous dykes of similar dimensions, particularly when the distances between the nearby tips of the segments become small in comparison with segment lengths. Most dykes become arrested and never supply magma to eruptions. Feeder-dykes normally reach the surface only along parts of their lengths (strike-dimensions). The volumetric flow or effusion rate of magma through a feeder-dyke or volcanic fissure depends on the aperture (opening) of the dyke or fissure in the 3rd power. All these theoretical and observational results are here applied to the dyke emplacements associated with the eruptions of Eyjafjallajökull 2010 and Bardarbunga-Holuhraun 2014. The results make it possible to

Ethnomedicinal knowledge among Karens of Andaman & Nicobar Islands, India.

PubMed

Chander, M Punnam; Kartick, C; Vijayachari, P

2015-03-13

This study documents the use of medicinal plants by Karens of Middle Andaman, of the Andaman and Nicobar Islands. In spite of the availability of modern medicines, Karens preferred herbal remedies provided by the Traditional Knowledge Practitioners (TKPs), who served as their healers. Hence, the aim of this study was to collect information from TKPs and determine the significance of plants utilized for medicinal purposes. The informant consensus factor (ICF) in relation to medicinal plants used was also estimated and analysed. Field research was conducted in three villages of Middle Andaman, inhabited by Karens, during October 2010 - February 2013. TKPs were interviewed with a questionnaire-guided ethno-medical survey protocol. The data obtained were analysed using the informant consensus factor (ICF) and use value (UV). Voucher specimens of all the cited plants were deposited at Regional Medical Research Centre (ICMR), Port Blair. Use of 78 medicinal plant species belonging to 71 genera encompassing 48 families was recorded during the survey. These plants were used to treat 38 different ailments, and divided into ten categories of use. The highest ICF value (0.79) was observed for infections and infestations. The Zingiberaceae and Fabaceae families exhibited the highest number of species, and the plants with the highest use values were Typha angustifolia L., Millingtonia hortensis L. f. and Piper betle L. The most common growth form observed were herbs (42%). Among the several plant parts used, leaves were mostly preferred for preparation of medicines. Water was the main excipient used for mixing the herbs. This study documents the use of medicinal plants by Karens of the Andaman and Nicobar Islands. Phytochemical and pharmacological aspects of these plants need to be studied, to confirm their efficacy and safety, and determine their potential use in modern medicine. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Performance and capacity of river dykes of protection against the floods", through elaboration of performance indicators and decision aid tool in view of the patrimonial assessment of river dykes

NASA Astrophysics Data System (ADS)

Vuillet, Marc; Peyras, Laurent; Serre, Damien; Diab, Youssef

2010-05-01

France and more generally the World have to face frequent episodes of devastating floods. The human and material damages are multiplied during the failure of a protection structure. In France the length of dykes is estimated to 7500 kilometers, protecting around 15 000 to 18 000 km² and an estimated population between 1.6 to 2 millions. Regrettably, these structures are most of the time old, unidentified, badly maintained, showing signs of weaknesses on numerous occasions. The management of these dikes raises then considerable problems to the decision-makers who are in charge of guaranteeing a maximal safety to the populations at a rational and acceptable management cost. The ambition of the project "Performance and capacity in the service of river dykes of protection against the floods" is to propose to Administrator scientific methods and technical tools for the management of river dykes. These tools will be capable of estimating the capacity in the service of dykes, and to define and organize into a hierarchy the actions of inspection, maintenance and repair. Scientific objectives: • To suggest a methodology of evaluation of the performance of river dykes • To identify and to understand the causes of variability (spatial and temporal) • To analyze the relation between the quality of the data and the quality of the profile of performance • To propose a methodology of auscultation and confortation of the information The research work consists in adapting functional analysis based on safety engineering method, in order to precise the role of each rivers dyke's component in regard to the mechanisms of degradation they suffer. It will allow us to identify failure indicators and decision criteria for evaluating the performance of dykes. The criteria will be the basis to develop a multicriteria decision aid tool allowing to determine the hierarchical organization and the selection of the sections of a park of dykes of protection against the floods, according

Volcaniclastic dykes tell on fracturing, explosive eruption and lateral collapse at Stromboli volcano (Italy)

NASA Astrophysics Data System (ADS)

Vezzoli, Luigina; Corazzato, Claudia

2016-05-01

In the upper part of the Stromboli volcano, in the Le Croci and Bastimento areas, two dyke-like bodies of volcanic breccia up to two-metre thick crosscut and intrude the products of Vancori and Neostromboli volcanoes. We describe the lithofacies association of these unusual volcaniclastic dykes, interpret the setting of dyke-forming fractures and the emplacement mechanism of internal deposits, and discuss their probable relationships with the explosive eruption and major lateral collapse events that occurred at the end of the Neostromboli period. The dyke volcaniclastic deposits contain juvenile magmatic fragments (pyroclasts) suggesting a primary volcanic origin. Their petrographic characteristics are coincident with the Neostromboli products. The architecture of the infilling deposits comprises symmetrically-nested volcaniclastic units, separated by sub-vertical boundaries, which are parallel to the dyke margins. The volcanic units are composed of distinctive lithofacies. The more external facies is composed of fine and coarse ash showing sub-vertical laminations, parallel to the contact wall. The central facies comprises stratified, lithic-rich breccia and lapilli-tuff, whose stratification is sub-horizontal and convolute, discordant to the dyke margins. Only at Le Croci dyke, the final unit shows a massive tuff-breccia facies. The volcaniclastic dykes experienced a polyphasic geological evolution comprising three stages. The first phase consisted in fracturing, explosive intrusion related to magma rising and upward injection of magmatic fluids and pyroclasts. The second phase recorded the dilation of fractures and their role as pyroclastic conduits in an explosive eruption possibly coeval with the lateral collapse of the Neostromboli lava cone. Finally, in the third phase, the immediately post-eruption mass-flow remobilization of pyroclastic deposits took place on the volcano slopes.

Petrogenesis of low-δ18O quartz porphyry dykes, Koegel Fontein complex, South Africa

NASA Astrophysics Data System (ADS)

Harris, Chris; Mulder, Kwenidyn; Sarkar, Saheli; Whitehead, Benjamin; Roopnarain, Sherissa

2018-04-01

This paper investigates the origin of low-δ18O quartz porphyry dykes associated with the 144-133 Ma Koegel Fontein Igneous Complex, which was intruded during the initial phase of breakup of Africa and South America. The 25-km diameter Rietpoort Granite is the largest and youngest phase of activity, and is roofed by a 10-km diameter pendant of gneiss. Quartz porphyry (QP) dykes, up to 15 m in width, strike NW-SE across the complex. The QP dykes that intruded outside the granite have similar quartz phenocryst δ18O values (average 8.0‰, ± 0.7, n = 33) to the granite (average 8.3 ± 1.0, n = 7). The QP dykes that intruded the roof pendant have quartz phenocrysts with more variable δ18O values (average 1.6‰, ± 2.1, n = 55). In some cases quartz phenocrysts have δ18O values as low as - 2.5‰. The variation in δ18O value within the quartz crystal population of individual dykes is small relative to the overall range, and core and rim material from individual quartz phenocrysts in three samples are identical within error. There is no evidence that quartz phenocryst δ18O values have been affected by fluid-rock interaction. Based on a Δquartz-magma value of 0.6‰, magma δ18O values must have been as low as - 3.1‰. Samples collected along the length of the two main QP dykes that traverse the roof pendant have quartz phenocryst δ18O values that range from + 1.1 to + 4.6‰, and - 2.3 to + 5.6‰, respectively. These δ18O values correlate negatively ( r = - 0.96) with initial 87Sr/86Sr, which can be explained by the event that lowered δ18O values of the source being older than the dykes. We suggest that the QP dykes were fed by magma produced by partial melting of gneiss, which had been variably altered at high temperature by 18O-depleted meteoric water during global glaciation at 550 Ma. The early melts had variable δ18O value but as melt pockets interconnected during melting, the δ18O values approached that of average gneiss. Variable quartz phenocryst �

Modelling of surface stresses and fracturing during dyke emplacement: Application to the 2009 episode at Harrat Lunayyir, Saudi Arabia

NASA Astrophysics Data System (ADS)

Al Shehri, Azizah; Gudmundsson, Agust

2018-05-01

Correct interpretation of surface stresses and deformation or displacement during volcanotectonic episodes is of fundamental importance for hazard assessment and dyke-path forecasting. Here we present new general numerical models on the local stresses induced by arrested dykes. In the models, the crustal segments hosting the dyke vary greatly in mechanical properties, from uniform or non-layered (elastic half-spaces) to highly anisotropic (layers with strong contrast in Young's modulus). The shallow parts of active volcanoes and volcanic zones are normally highly anisotropic and some with open contacts. The numerical results show that, for a given surface deformation, non-layered (half-space) models underestimate the dyke overpressure/thickness needed and overestimate the likely depth to the tip of the dyke. Also, as the mechanical contrast between the layers increases, so does the stress dissipation and associated reduction in surface stresses (and associated fracturing). In the absence of open contacts, the distance between the two dyke-induced tensile and shear stress peaks (and fractures, if any) at the surface is roughly twice the depth to the tip of the dyke. The width of a graben, if it forms, should therefore be roughly twice the depth to the tip of the associated arrested dyke. When applied to the 2009 episode at Harrat Lunayyir, the main results are as follows. The entire 3-7 km wide fracture zone/graben formed during the episode is far too wide to have been generated by induced stresses of a single, arrested dyke. The eastern part of the zone/graben may have been generated by the inferred, arrested dyke, but the western zone primarily by regional extensional loading. The dyke tip was arrested at only a few hundred metres below the surface, the estimated thickness of the uppermost part of the dyke being between about 6 and 12 m. For the inferred dyke length (strike dimension) of about 14 km, this yields a dyke length/thickness ratio between 2400 and 1200

Giant radiating dyke swarms on Earth and Venus

NASA Technical Reports Server (NTRS)

Ernst, Richard E.; Head, James W.; Parfitt, Elisabeth; Wilson, Lionel; Grosfils, Eric

1993-01-01

On Earth, giant radiating dyke swarms are usually preserved as fan-shaped fragments which have been dismembered from their original configuration by subsequent plate tectonic rifting events. Analysis of the largest fragments and consideration of their original configuration has led to the idea that many swarms are plume related, and that dyke swarms radiate away from plume centers. Magellan radar data reveal abundant intact giant radiating swarms on Venus which are similar in scale and pattern to those on Earth. The absence of intense weathering and plate tectonic processes on Venus accounts for the preservation of the primary radiating patterns. It is characteristic of both Earth and Venus that giant radiating dikes are emplaced laterally for distances of at least 2000 km away from plume centers. At distances beyond the influence of the plume on both Earth and Venus, the radiating dyke pattern is often swept into a linear pattern aligned with the regional stress field. There is tremendous potential synergism between the characterization and analysis of terrestrial dyke swarms (where significant erosion has revealed their structure and emplacement directions at depth) and the giant swarms of Venus (where the complete circumferential structure is preserved, and the surface fracture systems above near surface dikes and the nature of the central source regions are revealed). In this study, we report on the characteristics of radial dyke swarms on Earth and Venus and draw some preliminary comparisons from the two perspectives. In summary, on both planets there is evidence for plume-related magmatic centers associated with vertical and lateral injection of magma over considerable distances (up to at least 2000 km). The abundance of very broadly radiating swarms on Venus supports the notion that the swarms on Earth were radiating over broad sectors at the time of intrusion but were dissected by later events. The Venus data show that a swarm can change from radiating

Geological, geochemical and isotope diversity of 134 Ma dykes from the Florianópolis Dyke Swarm, Paraná Magmatic Province: Geodynamic controls on petrogenesis

NASA Astrophysics Data System (ADS)

Florisbal, L. M.; Janasi, V. A.; Bitencourt, M. F.; Nardi, L. V. S.; Marteleto, N. S.

2018-04-01

The Florianópolis Dyke Swarm (FDS), one of the major dyke swarms belonging to the Early cretaceous (135-131 Ma) Paraná Magmatic Province, is largely dominated by high Sr-Ti-P basalts that are confirmed here as feeders of the unique Urubici (= Khumib) lavas of the Paraná and Edendeka lava piles on the basis of their age and geochemistry. Our study integrates field, petrographic, whole-rock geochemistry, and Sr-Nd-Pb isotope geochemistry of representative samples from three main areas of exposition (Santa Catarina Island, Garopaba and Pinheira beaches), thus encompassing the whole extension of the FDS. Compared to the Urubici lavas, the dykes have usually higher contents of LILE and LREE, more radiogenic Sr and Pb, and more unradiogenic Nd, features attributed to a more pronounced interaction with melts derived from the country rocks registered in the basic magmas that remained in the conduits. Some of these dykes show strongly interactive contacts that must be part of a wider zone of crustal melting, probably more developed at greater depths. Small volumes of intermediate to acidic rocks form the cores of some composite dykes, and correspond to products of fractional crystallization from Urubici basalts contaminated with high Rb/Sr, and U/Th crustal melts (probably derived from Neoproterozoic granites), as indicated by geochemical and Sr-Nd-Pb isotope data. The chemical and isotope signatures of the less contaminated FDS basalts and related Urubici lavas do not show clear evidence of inputs from primitive mantle, and seem heavily influenced by enriched mantle. This suggests that the mantle wedge that was affected by subduction during the Neoproterozoic may have been frozen and coupled to the base of the lithospheric plate where the Early cretaceous magmatism occurred. A control of previous tectonic limits on the sources of the Urubici basalts seems evident, since they seem to be related to the younger lithosphere from the South Domain, related to the Florian

77 FR 26766 - Karen L. Blyth: Debarment Order

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-07

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2011-N-0880] Karen L. Blyth: Debarment Order AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The U.S. Food and Drug Administration (FDA) is issuing an order under the Federal Food, Drug, and...

The Role of Digital Literacy Practices on Refugee Resettlement: The Case of Three Karen Brothers

ERIC Educational Resources Information Center

Gilhooly, Daniel; Lee, Eunbae

2014-01-01

This study explores the social and cultural uses of digital literacies by adolescent immigrants to cope with their new lives in the United States. This case study focuses on three adolescent ethnic Karen brothers. Two years of participant observations in their home and Karen community, accompanied by formal and informal interviews, served as the…

Dyke-sill relationships in Karoo dolerites as indicators of propagation and emplacement processes of mafic magmas in the shallow crust

NASA Astrophysics Data System (ADS)

Coetzee, A.; Kisters, A. F. M.

2017-04-01

This paper describes the spatial and temporal relationships between Karoo-age (ca. 180 Ma) dolerite dykes and a regional-scale saucer-sill complex from the Secunda (coal mine) Complex in the northeastern parts of the Karoo Basin of South Africa. Unlike parallel dyke swarms of regional extensional settings, mafic dykes commonly show curved geometries and highly variable orientations, short strike extents and complex cross-cutting and intersecting relationships. Importantly, the dyke networks originate from the upper contacts of the first-order dolerite sill-saucer structure and are not the feeders of the saucer complex. Cross-cutting relationships indicate the largely contemporaneous formation of dykes and the inner sill and inclined sheets of the underlying saucer. Systematic dykes form a distinct boxwork-type pattern of two high-angle, interconnected dyke sets. The formation and orientation of this dyke set is interpreted to be related to the stretching of roof strata above elongated magma lobes that facilitated the propagation of the inner sill, similar to the "cracked lid" model described for large saucer complexes in Antarctica. Dyke patterns generally reflect the saucer emplacement process and the associated deformation of wall rocks rather than far-field regional stresses.

Producing Educational Learning Media Resources for Karen Children

ERIC Educational Resources Information Center

Chutataweesawas, Sirikoy; Tanchareon, Sumate; Wilang, Jeffrey Dawala

2018-01-01

To create appropriate educational learning media resources for the Karen community in Chiang Mai, Thailand, a project called 'The Research and Development Process of Multimedia Learning Resources' was initiated by a group of researchers from a top-ranked university in Bangkok. It consisted of picture books and an animation film derived from oral…

Early Detection of Eruptive Dykes Revealed by Normalized Difference Vegetation Index (NDVI) on Nyiragongo and Etna Volcanoes: Implications for Dyke Wedge Emplacement, Monitoring, and Risk Assessment.

NASA Astrophysics Data System (ADS)

Komorowski, J.; Houlié, N.; Kasereka, C. M.; Ciraba, H.

2006-12-01

Flank-fissure eruptions involve lateral injection and propagation of magma in a volcanic edifice along pre- existing fractures in the direction of a volcanic rift zone (VRZ) where magma intrusion and lava flow production are concentrated over time. Gradual dyke wedge emplacement on volcano flanks and in VRZ's does not necessarily trigger large amplitude deformation signals susceptible to be recorded months or even years before the actual eruption. We show that active and potentially eruptive areas in a VRZ can be detected up to 2 years before the arrival to the surface of the final eruptive dyke and venting of lava flows by processing satellite images applying a Normalized Difference Vegetation Index (NDVI) algorithm. A positive NDVI anomaly is indicative of excessive photosynthetic plant activity. A posteriori analysis of satellite images reveal that a high- NDVI linear anomaly was apparent in vegetated areas of VRZ's on Etna from 2000 to 2002 and on Nyiragongo in June 2001, several months to years before eruptive fractures formed directly above the NDVI anomaly. We propose that the observed NDVI linear anomalies are the signature of the integrated physico-chemical effects (increased heat and CO2 flux, H2O condensation) caused by the structurally-controlled progressive injection and propagation, in a VRZ and a few months to years before the eruption, of a series of dykes (dyke wedge) that did not reach the surface. We focus of Nyiragongo volcano where historical flank-fissure eruptions from lava lake drainage in 1977 and 2002 show a link with tectonics of the Kivu rift (western branch of the East African Rift System). In 2002, dykes were injected in the southern VRZ bounded by Kivu rift normal faults and propagated over 14 km producing lava flows that caused widespread destruction in the city of Goma. Data from Nyiragongo suggest that as a dyke wedge is formed and repeatedly reactivated, final eruptive dykes can be injected easily and can propagate rapidly further

Early Jurassic mafic dykes from the Xiazhuang ore district (South China): Implications for tectonic evolution and uranium metallogenesis

NASA Astrophysics Data System (ADS)

Wang, Lian-Xun; Ma, Chang-Qian; Lai, Zhong-Xin; Marks, Michael A. W.; Zhang, Chao; Zhong, Yu-Fang

2015-12-01

A comprehensive study on zircon U-Pb age dating, whole-rock geochemistry and Sr-Nd isotope data has been conducted on the mafic rocks of the Xiazhuang uranium ore district and adjacent regions in South China. Based on field work and petrographic features, three rock types (the Kuzhukeng gabbro, the WNW-trending dolerite dykes and the NNE-trending lamprophyre dykes) are distinguished. Early Jurassic SHRIMP and LA-ICPMS ages of zircon for the Kuzhukeng gabbro (198 ± 1 Ma) and WNW-trending dolerite dykes (193 ± 4 Ma) have been obtained, which are 50 Ma older than previously thought (being Cretaceous). These geochronologic data provide new evidence for the rarely identified Early Jurassic magmatisms in South China. Whole-rock geochemical data for the Kuzhukeng gabbro and WNW-trending dolerite dykes are similar, both of which being higher in FeO and TiO2 but lower in SiO2 and K2O than the NNE-trending lamprophyre dykes. Trace element characteristics and Sr-Nd isotope data indicate arc-like signatures similar to the Cretaceous southeast coast basalts of China for the lamprophyre dykes, but an OIB-like geochemical affinity for the high-TiO2 mafic rocks similar to the Permo/Triassic Emeishan flood basalts and the Middle Jurassic Ningyuan alkaline basalts. We propose that the lamprophyre dykes formed in an arc volcanic system driven by the subduction of the paleo-Pacific plate. In contrast, the Kuzhukeng gabbro and associated dolerite dykes record the post-orogenic (Indosinian) extension event in the Tethyan tectonic regime. This further implies that the Indosinian extension may have lasted until the Early Jurassic, and therefore, the subduction of the paleo-Pacific plate in south China was probably later than this period. Most U deposits of the Xiazhuang area are located at the intersection between the WNW-trending dolerite dykes and the NNE-trending faults within the Triassic granites of eastern Guidong complex, South China. Previous metallogenesis studies assumed that

Assessment of the Psychosocial Development of Children Attending Nursery Schools in Karen Refugee Camps in Thailand

ERIC Educational Resources Information Center

Tanaka, Akiko

2013-01-01

The Karen, an ethnic minority group in Burma, have experienced a prolonged state of exile in refugee camps in neighboring Thailand because of ethnic conflict in their home country. Nursery schools in the three largest Karen refugee camps aim to promote the psychosocial development of young children by providing a child-centered, creative,…

Seismic footprints of shallow dyke propagation at Etna, Italy.

PubMed

Falsaperla, Susanna; Neri, Marco

2015-07-15

One of the key issues in forecasting volcanic eruptions is to detect signals that can track the propagation of dykes towards the surface. Continuous monitoring of active volcanoes helps significantly in achieving this goal. The seismic data presented here are unique, as they document surface faulting processes close (tens to a few hundred meters) to their source, namely the dyke tip. They originated nearby - and under - a seismic station that was subsequently destroyed by lava flows during eruptive activity at Etna volcano, Italy, in 2013. On February 20, a ~600 m-long and ~120 m wide NW-SE fracture field opened at an altitude between 2750 and 2900 m. The consequent rock dislocation caused the station to tilt and offset the seismic signal temporarily. Data acquisition continued until the arrival of the lava flow that led to the breakdown of the transmission system. Shallow ground fracturing and repeated low-frequency oscillations occurred during two stages in which the seismic signal underwent a maximum offset ~2.57 × 10(4) nm/s. Bridging instrumental recordings, fieldwork and conceptual modelling, these data are interpreted as the seismic footprints of a magmatic dyke intrusion that moved at speed ~0.02 m/s (first stage) and 0.46 m/s (second stage).

Ultramafic lavas and high-Mg basaltic dykes from the Othris ophiolite complex, Greece

NASA Astrophysics Data System (ADS)

Baziotis, Ioannis; Economou-Eliopoulos, Maria; Asimow, Paul D.

2017-09-01

We evaluate the petrography and geochemistry of an unusual suite of subduction-related Phanerozoic high-MgO rocks from the Othris ophiolite complex in Greece, some of which have previously been described as komatiitic lavas. In particular, we study ultramafic, olivine-phyric lavas from the Agrilia area and high-Mg basaltic dykes from the Pournari area. We seek to define primary magmatic MgO contents and initial liquidus temperatures as well as the differentiation sequence and cooling rates experienced by the lavas and dykes. One of our goals is to relate the Othris case to known komatiite and boninite occurrences and to address whether Othris documents an important new constraint on the temporal evolution of ambient mantle temperature, plume-related magmatism, and subduction of oceanic lithosphere. We conclude that, despite whole-rock MgO contents of 31-33 wt%, the olivine-phyric lavas at Agrilia had an upper limit liquid MgO content of 17 wt% and are therefore picrites, not komatiites. The Agrilia lavas contain the unusual Ti-rich pyroxenoid rhönite; we discuss the significance of this occurrence. In the case of the Pournari high-Mg dykes, the distinctive dendritic or plumose clinopyroxene texture, though it resembles in some ways the classic spinifex texture of komatiites, is simply evidence of rapid cooling at the dyke margin and not evidence of extraordinarily high liquidus temperatures. We correlate the dendritic texture with disequilibrium mineral chemistry in clinopyroxene to constrain the cooling rate of the dyke margins.

Magmatic dyke swarms of the south shetland islands volcanic arc, west-antarctica - tracers of geodynamic history

NASA Astrophysics Data System (ADS)

Kraus, St.; Miller, H.

2003-04-01

Magmatic dykes are essential components of volcanic arcs, following joint systems and fracture zones. This work aims to reconstruct the deformational and intrusive history of the northern part of the Antarctic Peninsula by combining structural information with the geochemistry, isotopy and age of the dykes. On the South Shetland Islands volcanic activity began about 130 Ma ago. From Mid to Late Eocene (49-34 Ma) the northern Antarctic Peninsula and southern South America underwent extensional tectonics, which led to sea-floor spreading in the Drake Passage 28 Ma ago. Subsequent slab-rollback caused arc-extension and the opening of the Bransfield Rift as a backarc-basin between 4 and 1.3 Ma ago. Very slow subduction (1mm/a) at the South Shetland trench continues until the present day. Several changes of subduction direction caused crucial variations regarding the tectonic regime in the overlying South Shetland block, being the reason for the shifting strike of the dykes. Several dyke systems were mapped in areas of up to 100000m2, with the outcrop situation being good enough to observe plenty of relative age relationships. ICP-MS geochemical analysis on 132 dykes shows, as expected, that the majority of them correspond to a typical subduction-related calcalcalic suite, ranging from basalts to rhyolites. Nevertheless, some dykes show shoshonitic characteristics and are maybe related to an early stage extensional crustal regime. This is supported by the relative ages observed in the field, indicating, that these dykes belong to the oldest ones outcropping in the investigated area. In one case, the geochemical behaviour of the dyke corresponds clearly to adacitic conditions, being a hint on partially molten subducted oceanic crust. In several areas (e.g. Potter Peninsula, King George Island, and Hurd Peninsula, Livingston Island) a strong correlation between chemism and strike of the dykes - and therefore the tectonic regime at the time of intrusion - is observed. Ce

The Errors of Karen Franklin's Pretextuality

PubMed Central

Cantor, James M.

2012-01-01

In her recent article, Hebephilia: Quintessence of Diagnostic Pretextuality (published in Behavioral Sciences and the Law, 2010), Karen Franklin expands on her previous argument that psychologists and psychiatrists should not diagnose as abnormal hebephilia, the sexual preference for early pubescent children. She supports her argument with a series of claims about the contents of the empirical literature and the scientists who produced it. The present document provides fact-checking of those claims, revealing that Franklin's conclusions are based largely on demonstrable falsehoods. PMID:22745581

Eocene slab breakoff of Neotethys as suggested by dioritic dykes in the Gangdese magmatic belt, southern Tibet

NASA Astrophysics Data System (ADS)

Ma, Xuxuan; Xu, Zhiqin; Meert, Joseph G.

2016-04-01

The Gangdese magmatic belt in southern Tibet demarcates an important boundary between the Indian and Eurasian plates. Due to its location and magmatic evolutionary history, it is key to understanding both the history of Neotethys closure and the Indo-Asian collisional process. This study presents new geochronological and geochemical data for dioritic dykes in the southern Gangdese magmatic belt in southern Tibet. U-Pb geochronological results reveal that the dykes were emplaced at ca. 41 Ma and thus broadly coeval with the 40-38 Ma Dazi volcanics and the 42-40 Ma Gaoligong-Tengliang basaltic dykes. Geochemically, these dykes are characterized by alkaline signature, high Mg# (57-63) and low TiO2 contents ( 0.9-1.0), showing notable enrichment of light rare earth elements relative to the heavy rare earth elements, enrichment of incompatible elements (i.e. Cs, Rb, Ba, Th and U), and depletion of high field strength elements (i.e. Nb, Ta and Ti). In addition, a large variation of zircon εHf(t) values (- 10 to + 13) was shown, implying heterogeneity of magma sources. A heterogeneous source is also suggested by the occurrence of xenocrysts in the dykes. These observations suggest that the magma source of the dykes was dominated by partial melting of lithospheric mantle and then subsequently contaminated by crustal material during ascent. In combination with other geological data in the region, we suspect that the slab slicing of the Neotethys played a key role in the formation of the lithospheric mantle-derived dioritic dykes and adakitic granite, asthenosphere-derived volcanics, basaltic dykes, as well as the recently reported strongly fractionated granites.

Earth's magnetic field strength in the Early Cambrian: Thellier paleointensity estimates of Itabaiana mafic dykes, Northeast Brazil

NASA Astrophysics Data System (ADS)

Trindade, R. I. F.; Macouin, M.; Poitou, C.; Chauvin, A.; Hill, M.

2012-04-01

Thellier's paleointensity and microwave paleointensity experiments were carried out in Early Cambrian dykes from Itabaiana (NE Brazil) dated at 525 ±5 Ma. A previous paleomagnetic study on these dykes reveals a very stable characteristic component, whose thermoremanent nature is confirmed by positive baked contact tests performed in three different dykes. The main magnetic carrier is Ti-poor to pure magnetite in the PSD to SD domain state. Hysteresis parameters and first-order reversal curve (FORC) diagrams will be presented in order to apprehend the two different behaviors that characterize the samples during paleointensity experiments. From the 96 samples (from 13 dykes) analyzed in two laboratories using slightly different Thellier's experimental protocols, we have retained 12 samples (3 dykes) for paleointensity estimates. Paleointensity values range from 18.1 up to 40 μΤ. This corresponds to equivalent VDMs of 4.3 ± 0.5, 4.4 ± 1.4 and 5.3 ± 0.9 x 1022 Am2, for the three dykes respectively. These results, the first obtained for rapidly cooled Cambrian rocks, document a moderate Earth field in the Precambrian-Cambrian transition.

Petrogenesis of peralkaline granite dykes of the Straumsvola complex, western Dronning Maud Land, Antarctica

NASA Astrophysics Data System (ADS)

Harris, Chris; Dreyer, Tanya; le Roux, Petrus

2018-01-01

Peralkaline syenite and granite dykes cut the Straumsvola nepheline syenite pluton in Western Dronning Maud Land, Antarctica. The average peralkalinity index (PI = molecular Al/[Na + K]) of the dykes is 1.20 ( n = 29) and manifests itself in the presence of the Zr silicates eudialyte, dalyite and vlasovite, and the Na-Ti silicate, narsarsukite. The dykes appear to have intruded during slow cooling of the nepheline syenite pluton, and the petrogenetic relationship of the dykes and the pluton cannot be related to closed-system processes at low pressure, given the thermal divide that exists between silica-undersaturated and oversaturated magmas. Major and trace element variations in the dykes are consistent with a combination of fractional crystallization of parental peralkaline magma of quartz trachyte composition, and internal mineral segregation prior to final solidification. The distribution of accessory minerals is consistent with late-stage crystallization of isolated melt pockets. The dykes give an Rb-Sr isochron age of 171 ± 4.4 Ma, with variable initial 87Sr/86Sr ratio (0.7075 ± 0.0032), and have an average ɛ Nd of - 12.0. Quartz phenocrysts have δ18O values of 8.4-9.2‰, which are generally in O-isotope equilibrium with bulk rock. Differences in the δ18O values of quartz and aegirine (average Δquartz-aegirine = 3.5‰) suggest aegirine formation temperatures around 500 °C, lower than expected for a felsic magma, but consistent with poikilitic aegirine that indicates subsolidus growth. The negative ɛ Nd (< - 10) and magma δ18O values averaging 8.6‰ (assuming Δquartz-magma = 0.6‰) are inconsistent with a magma produced by closed-system fractional crystallization of a mantle-derived magma. By contrast, the nepheline syenite magma had mantle-like δ18O values and much less negative ɛ Nd (average - 3.1, n = 3). The country rock has similar δ18O values to the granite dykes (average 8.0‰, n = 108); this means that models for the petrogenesis of

Davidoff-Dyke-Masson Syndrome Presenting as Childhood Schizophrenia.

ERIC Educational Resources Information Center

White, James H.; Rust, John B.

1979-01-01

The article presents a case history of a child displaying symptoms of schizophrenia, seizures, and retardation without neurological abnormalities, which were eventually diagnosed as being due to Davidoff-Dyke-Masson syndrome, a condition involving gross anatomical brain pathology. (DLS)

Polycrystalline magma behaviour in dykes: Insights from high-resolution numerical models

NASA Astrophysics Data System (ADS)

Yamato, Philippe; Duretz, Thibault; Tartèse, Romain; May, Dave

2013-04-01

The presence of a crystalline load in magmas modifies their effective rheology and thus their flow behaviour. In dykes, for instance, the presence of crystals denser than the melt reduces the ascent velocity and modifies the shape of the velocity profile from a Newtonian Poiseuille flow to a Bingham type flow. Nevertheless, several unresolved issues still remain poorly understood and need to be quantified: (1) What are the mechanisms controlling crystals segregation during magma ascent in dykes? (2) How does crystals transportation within a melt depend on their concentration, geometry, size and density? (3) Do crystals evolve in isolation to each other or as a cluster? (4) What is the influence of considering inertia of the melt within the system? In this study, we present numerical models following the setup previously used in Yamato et al. (2012). Our model setup simulates an effective pressure gradient between the base and the top of a channel (representing a dyke), by pushing a rigid piston into a magmatic mush that comprised crystals and melt and perforated by a hole. The initial resolution of the models (401x1551 nodes) has been doubled in order to ensure that the smallest crystalline fractions are sufficiently well resolved. Results show that the melt phase can be squeezed out from a crystal-rich magma when subjected to a given pressure gradient range and that clustering of crystals might be an important parameter controlling their behaviour. This demonstrates that crystal-melt segregation in dykes during magma ascent constitutes a viable mechanism for magmatic differentiation of residual melts. These results also explain how isolated crystal clusters and melt pockets, with different chemistry, can be formed. In addition, we discuss the impact of taking into account inertia in our models. Reference: Yamato, P., Tartèse, R., Duretz, T., May, D.A., 2012. Numerical modelling of magma transport in dykes. Tectonophysics 526-529, 97-109.

Variscan potassic dyke magmatism of durbachitic affinity at the southern end of the Bohemian Massif (Lower Austria)

NASA Astrophysics Data System (ADS)

Zeitlhofer, Helga; Grasemann, Bernhard; Petrakakis, Konstantin

2016-06-01

Dykes in the Strudengau area (SW Moldanubian Zone, Austria) can be mineralogically divided into lamprophyres (spessartites and kersantites) and felsic dykes (granite porphyries, granitic dykes and pegmatoid dykes). Geochemical analyses of 11 lamprophyres and 7 felsic dykes show evidence of fractional crystallization. The lamprophyres are characterized by metaluminous compositions, intermediate SiO2 contents and high amounts of MgO and K2O; these rocks have high Ba (800-3000 ppm) and Sr (250-1000 ppm) contents as well as an enrichment of large-ion lithophile elements over high field strength elements, typical for enriched mantle sources with variable modifications due to fractionation and crustal contamination. This geochemical signature has been reported from durbachites (biotite- and K feldspar-rich mela-syenites particularly characteristic of the Variscan orogen in Central Europe). For most major elements, calculated fractionation trends from crystallization experiments of durbachites give an excellent match with the data from the Strudengau dykes. This suggests that the lamprophyres and felsic dykes were both products of fractional crystallization and subsequent magma mixing of durbachitic and leucogranitic melts. Rb-Sr geochronological data on biotite from five undeformed kersantites and a locally deformed granite porphyry gave cooling ages of c. 334-318 Ma, indicating synchronous intrusion of the dykes with the nearby outcropping Weinsberger granite (part of the South Bohemian Batholith, c. 330-310 Ma). Oriented matrix biotite separated from the locally deformed granite porphyry gave an Rb-Sr age of c. 318 Ma, interpreted as a deformation age during extensional tectonics. We propose a large-scale extensional regime at c. 320 Ma in the Strudengau area, accompanied by plutonism of fractionated magmas of syncollisional mantle-derived sources, mixed with crustal components. This geodynamic setting is comparable to other areas in the Variscan belt documenting an

Seismic footprints of shallow dyke propagation at Etna, Italy

PubMed Central

Falsaperla, Susanna; Neri, Marco

2015-01-01

One of the key issues in forecasting volcanic eruptions is to detect signals that can track the propagation of dykes towards the surface. Continuous monitoring of active volcanoes helps significantly in achieving this goal. The seismic data presented here are unique, as they document surface faulting processes close (tens to a few hundred meters) to their source, namely the dyke tip. They originated nearby - and under - a seismic station that was subsequently destroyed by lava flows during eruptive activity at Etna volcano, Italy, in 2013. On February 20, a ~600 m-long and ~120 m wide NW-SE fracture field opened at an altitude between 2750 and 2900 m. The consequent rock dislocation caused the station to tilt and offset the seismic signal temporarily. Data acquisition continued until the arrival of the lava flow that led to the breakdown of the transmission system. Shallow ground fracturing and repeated low-frequency oscillations occurred during two stages in which the seismic signal underwent a maximum offset ~2.57 × 104 nm/s. Bridging instrumental recordings, fieldwork and conceptual modelling, these data are interpreted as the seismic footprints of a magmatic dyke intrusion that moved at speed ~0.02 m/s (first stage) and 0.46 m/s (second stage). PMID:26173557

Effect of volcanic dykes on coastal groundwater flow and saltwater intrusion: A field-scale multiphysics approach and parameter evaluation

NASA Astrophysics Data System (ADS)

Comte, J.-C.; Wilson, C.; Ofterdinger, U.; González-Quirós, A.

2017-03-01

Volcanic dykes are common discrete heterogeneities in aquifers; however, there is a lack of field examples of, and methodologies for, comprehensive in situ characterization of their properties with respect to groundwater flow and solute transport. We have applied an integrated multiphysics approach to quantify the effect of dolerite dykes on saltwater intrusion in a coastal sandstone aquifer. The approach involved ground geophysical imaging (passive magnetics and electrical resistivity tomography), well hydraulic testing, and tidal propagation analysis, which provided constraints on the geometry of the dyke network, the subsurface saltwater distribution, and the sandstone hydrodynamic properties and connectivity. A three-dimensional variable-density groundwater model coupled with a resistivity model was further calibrated using groundwater and geophysical observations. A good agreement of model simulations with tide-induced head fluctuations, geophysically derived pore water salinities, and measured apparent resistivities was obtained when dykes' hydraulic conductivity, storativity, and effective porosity are respectively about 3, 1, and 1 orders of magnitude lower than the host aquifer. The presence of the dykes results in barrier-like alterations of groundwater flow and saltwater intrusion. Preferential flow paths occur parallel to observed dyke orientations. Freshwater inflows from upland recharge areas concentrate on the land-facing side of the dykes and saltwater penetration is higher on their sea-facing side. This has major implications for managing groundwater resources in dyke-intruded aquifers, including in coastal and island regions and provides wider insights on preferential pathways of groundwater flow and transport in highly heterogeneous aquifer systems.

The Case of Three Karen Refugee Women and Their Children: Literacy Practices in a Family Literacy Context

ERIC Educational Resources Information Center

Quadros, Sabrina; Sarroub, Loukia K.

2016-01-01

The lack of research about the Karen, one of 135 ethnic groups from Myanmar limits literacy educators charged with educating this refugee population in public schools. In this case study the authors explore the literacy practices of Karen families when at school and in their homes and within an ESL family literacy program. The case of these…

Dykes as Tracers of Continental Break-up: Argon Geochronology of Mesozoic Flood Basalts of Western Dronning Maud Land, Antarctica

NASA Astrophysics Data System (ADS)

Fazel, A.; Kelley, S. P.; Leat, P. T.; Hawkesworth, C.

2003-04-01

The British Antarctic Survey MAMOG Project (Magmatism as A Monitor Of Gondwana break up processes) is investigating the mantle processes that resulted in the eruption of the Karoo-Dronning Maud Land CFB suite and its importance in our understanding of the initial stages of Gondwana break-up. One of the problems of understanding the 180Ma continental flood basalts is knowing their precise age. Since they are erupted through more ancient (1000Ma) rocks we have to use the Ar-Ar dating technique to determine whether they are related to the continental break-up or are part of some older event. In addition, we have analysed the chemistry of the dykes and can relate them to several chemical types, the challenge is to test if dykes with similar chemistry all erupted at the same time. It has been suggested that many of the Jurassic dykes in western DML fed the CFB suite that is higher in the volcanic pile. We have found dykes of different ages in the Kirwanveggen and Ahlmannryggen regions of western DML. Although more work needs to be done, we now have mounting evidence to suggest that episodes of chemically similar magmatism in DML stretched from 1000-180Ma with some events separated by hundreds of millions of years implying a lithospheric mantle control on magma composition. The precise ages for the dykes are slightly younger than the accepted ages for the South African Karoo province. In addition to determining the ages of dyke intrusions, a high spatial resolution UV laser has been used to measure argon loss from diorite host rocks adjacent to the dykes. Progressive heating of the country rock during magma emplacement causes argon loss. Thermal modelling of the dykes will allow us to differentiate between various heat loss mechanisms and give an indication of the style, volume and rapidity of magma flow through the dyke. The UV results have shown that some of the dykes were active for long periods probably feeding the surface lava eruptions.

New paleomagnetic results on ˜ ˜2367 Ma Dharwar giant dyke swarm, Dharwar craton, southern India: implications for Paleoproterozoic continental reconstruction

NASA Astrophysics Data System (ADS)

Babu, N. Ramesh; Venkateshwarlu, M.; Shankar, Ravi; Nagaraju, E.; Parashuramulu, V.

2018-02-01

Here we report new paleomagnetic results and precise paleopole position of the extensional study on ˜ 2367 Ma mafic giant radiating dyke swarm in the Dharwar craton, southern India. We have sampled 29 sites on 12 dykes from NE-SW Karimnagar-Hyderabad dykes and Dhone-Gooty sector dykes, eastern Dharwar craton to provide unambiguous paleomagnetism evidence on the spectacular radiating dyke swarm and thereby strengthening the presence of single magmatic event at ˜ 2367 Ma. A total of 158 samples were subjected to detailed alternating field and thermal demagnetization techniques and the results are presented here along with previously reported data on the same dyke swarm. The remanent magnetic directions are showing two components, viz., seven sites representing four dykes show component (A) with mean declination of 94{{}°} and mean inclination of - 70{{}°} (k=87, α_{95}=10{{}°}) and corresponding paleopole at 16{{}°}N, 41{{}°}E (dp=15{{}°} and dm=17{{}°}) and 22 sites representing 8 dykes yielded a component (B) with mean declination of 41{{}°} and mean inclination of - 21{{}°} (k=41, α_{95}=9{{}°}) with a paleopole at 41{{}°}N, 200{{}°}E (dp=5{{}°} and dm=10{{}°}). Component (A) results are similar to the previously reported directions from the ˜ 2367 Ma dyke swarm, which have been confirmed fairly reliably to be of primary origin. The component (B) directions appear to be strongly overprinted by the 2080 Ma event. The grand mean for the primary component (A) combined with earlier reported studies gives mean declination of 97{{}°} and mean inclination of - 79{{}°} (k=55, α_{95}=3{{}°}) with a paleopole at 15{{}°}N, 57{{}°}E (dp=5{{}°}, dm=6{{}°}). Paleogeographical position for the Dharwar craton at ˜ 2367 Ma suggests that there may be a chance to possible spatial link between Dharwar dykes of Dharwar craton (India), Widgemooltha and Erayinia dykes of Yilgarn craton (Australia), Sebanga Poort Dykes of Zimbabwe craton (Africa) and Karelian

Author! Author! Noted Writer of Historical Fiction: Karen Cushman

ERIC Educational Resources Information Center

Brodie, Carolyn S.

2004-01-01

This article gives a brief biography of author Karen Cushman, best known for the attention to detail and thorough research that goes into her historical novels. Her first two novels, "Catherine, Called Birdy" and "The Midwife's Apprentice" were both Newbery Medal winners. A selected bibliography, as well as a list of related resources, is also…

Dedicated to Gifted Education: An Interview with Karen Rogers

ERIC Educational Resources Information Center

Hay, Peta

2017-01-01

Karen B. Rogers has dedicated her career to serving gifted students. In this interview she outlines her major research studies, and explores some of her experiences in the field, with special emphasis on her time in Australia. She discusses her use of the meta-synthesis and meta-analysis methodologies, and outlines key areas of gifted education…

Crystallisation sequence and magma evolution of the De Beers dyke (Kimberley, South Africa)

NASA Astrophysics Data System (ADS)

Soltys, Ashton; Giuliani, Andrea; Phillips, David

2018-06-01

We present petrographic and mineral chemical data for a suite of samples derived from the De Beers dyke, a contemporaneous, composite intrusion bordering the De Beers pipe (Kimberley, South Africa). Petrographic features and mineral compositions indicate the following stages in the evolution of this dyke: (1) production of antecrystic material by kimberlite-related metasomatism in the mantle (i.e., high Cr-Ti phlogopite); (2) entrainment of wall-rock material during ascent through the lithospheric mantle, including antecrysts; (3) early magmatic crystallisation of olivine (internal zones and subsequently rims), Cr-rich spinel, rutile, and magnesian ilmenite, probably on ascent to the surface; and (4) crystallisation of groundmass phases (i.e., olivine rinds, Fe-Ti-rich spinels, perovskite, apatite, monticellite, calcite micro-phenocrysts, kinoshitalite-phlogopite, barite, and baddeleyite) and the mesostasis (calcite, dolomite, and serpentine) on emplacement in the upper crust. Groundmass and mesostasis crystallisation likely forms a continuous sequence with deuteric/hydrothermal modification. The petrographic features, mineralogy, and mineral compositions of different units within the De Beers dyke are indistinguishable from one another, indicating a common petrogenesis. The compositions of antecrysts (i.e., high Cr-Ti phlogopite) and magmatic phases (e.g., olivine rims, magnesian ilmenite, and spinel) overlap those from the root zone intrusions of the main Kimberley pipes (i.e., Wesselton, De Beers, Bultfontein). However, the composition of these magmatic phases is distinct from those in `evolved' intrusions of the Kimberley cluster (e.g., Benfontein, Wesselton water tunnel sills). Although the effects of syn-emplacement flow processes are evident (e.g., alignment of phases parallel to contacts), there is no evidence that the De Beers dyke has undergone significant pre-emplacement crystal fractionation (e.g., olivine, spinel, ilmenite). This study demonstrates the

Late Cretaceous dacitic dykes swarm from Central Iran, a trace for amphibolite melting in a subduction zone

NASA Astrophysics Data System (ADS)

Nosouhian, N.; Torabi, G.; Arai, S.

2016-05-01

Late Cretaceous Bayazeh dyke swarm is situated in the western part of the Central-East Iranian Microcontinent (CEIM). These dykes with a dominant northeast-southwest trend occur in the Eastern margin of the Yazd block. They cross cut the Lower Cretaceous sedimentary rocks. The length of the Bayazeh dykes occasionally reaches up to the 2 km. Rock forming minerals of these dykes are plagioclase (andesine and oligoclase), amphibole (magnesio-hastingsitic hornblende, magnesio-hornblende and tschermakitic hornblende), quartz, K-feldspar (orthoclase), zircon and apatite. Secondary minerals are chlorite (pycnochlorite), albite, magnetite and calcite. The main textures are porphyritic, glomeroporphyritic and poikilitic. The felsic character of the Bayazeh dacitic dykes is shown by their high SiO2 (62.70 to 64.60 wt %) and low [Fe2O3* + MgO + MnO + TiO2] (average 4.64 wt %) contents. These dykes represent the peraluminous to metaluminous nature and their Na2O and K2O values are 5.20-7.14 and 1.51-2.59 wt %, respectively, which reveal their sodic chemistry. The trace element characteristics are the LREE enrichment relative to HREE, [La/Yb]CN = 13.27-22.99, and slightly negative or positive Eu anomaly. These geochemical characteristics associated with low Nb/La (0.16-0.25), Yb/Nd (0.04-0.05) and high Zr/Sm (37.60-58.25) ratios indicate that the melting of a metamorphosed subducted oceanic crust is occurred where the residual mineral assemblage is dominated by garnet amphibolite. The chemical compositions of the Bayazeh dykes resemble those of slab-derived tonalite-trondhjemite-granodiorite (TTG) series. They were formed by subduction of Mesozoic Neo-Tethys -related Nain and Ashin oceanic crusts.

Magnetic fabric and flow direction in the Ediacaran Imider dyke swarms (Eastern Anti-Atlas, Morocco), inferred from the Anisotropy of Magnetic Susceptibility (AMS)

NASA Astrophysics Data System (ADS)

Otmane, Khadija; Errami, Ezzoura; Olivier, Philippe; Berger, Julien; Triantafyllou, Antoine; Ennih, Nasser

2018-03-01

Located in the Imiter Inlier (Eastern Saghro, Anti-Atlas, Morocco), Ediacaran volcanic dykes have been studied for their petrofabric using Anisotropy of Magnetic Susceptibility (AMS) technique. Four dykes, namely TF, TD, FF and FE show andesitic compositions and are considered to belong to the same dyke swarm. They are oriented respectively N25E, N40E, N50E, and N10E and have been emplaced during a first tectonic event. The dyke FW, oriented N90E displays a composition of alkali basalt and its emplacement is attributed to a subsequent tectonic event. These rocks are propylitized under greenschist facies conditions forming a secondary paragenesis constituted by calcite, chlorite, epidote and sericite. The dykes TF, TD, FF and FE are sub-volcanic calc-alkaline, typical of post-collisional basalts/andesites, belonging to plate margin andesites. The FW dyke shows a within-plate basalt signature; alkaline affinity reflecting a different petrogenetic process. The thermomagnetic analyses show a dominantly ferromagnetic behaviour in the TF dyke core carried by single domain Ti-poor magnetite, maghemite and pyrrhotite. The dominantly paramagnetic susceptibilities in TF dyke rims and TD, FE, FF and FW dykes are controlled by ilmenite, amphibole, pyroxene and chlorite. The magnetic fabrics of the Imider dykes, determined by our AMS study, allows us to reconstitute the tectonic conditions which prevailed during the emplacement of these two generations of volcanic dykes. The first tectonic event was characterized by a roughly NE-SW compression and the second tectonic event is characterized by an E-W shortening followed by a relaxation recording the end of the Pan-African orogeny in the eastern Anti-Atlas.

Unlocking Families' Potential: A Conversation with Karen L. Mapp

ERIC Educational Resources Information Center

Thiers, Naomi

2017-01-01

Karen L. Mapp--former Deputy Superintendent for Family and Community Engagement for Boston's schools and noted researcher and author on how schools can partner with families--talks with "EL" editor Naomi Thiers on the need to approach engaging family caregivers in students' learning in a new way, starting with emphasizing active…

Magmatic dyking and recharge in the Asal Rift, Republic of Djibouti

NASA Astrophysics Data System (ADS)

Peltzer, G.; Harrington, J.; Doubre, C.; Tomic, J.

2012-12-01

The Asal Rift, Republic of Djibouti, has been the locus of a major magmatic event in 1978 and seems to have maintained a sustained activity in the three decade following the event. We compare the dyking event of 1978 with the magmatic activity occurring in the rift during the 1997-2008 time period. We use historical air photos and satellite images to quantify the horizontal opening on the major faults activated in 1978. These observations are combined with ground based geodetic data acquired between 1973 and 1979 across the rift to constrain a kinematic model of the 1978 rifting event, including bordering faults and mid-crustal dykes under the Asal Rift and the Ghoubbet Gulf. The model indicates that extension was concentrated between the surface and a depth of 3 km in the crust, resulting in the opening of faults, dykes and fissures between the two main faults, E and gamma, and that the structure located under the Asal Rift, below 3 km, deflated. These results suggest that, during the 1978 event, magmatic fluids transferred from a mid-crustal reservoir to the shallow structures, injecting dykes and filling faults and fissures, and reaching the surface in the Ardoukoba fissural eruption. Surface deformation observed by InSAR during the 1997-2008 decade reveals a slow, yet sustained inflation and extension across the Asal Rift combined with continuous subsidence of the rift inner floor. Modeling shows that these observations cannot be explained by visco-elastic relaxation, a process, which mostly vanishes 20 to 30 years after the 1978 event. However, the InSAR observations over this decade are well explained by a kinematic model in which an inflating body is present at mid-crustal depth, approximately under the Fieale caldera, and shallow faults accommodate both horizontal opening and down-dip slip. The total geometric moment rate, or inflation rate, due to the opening of the mid-crustal structure and the deeper parts of the opening faults is 3 106 m3yr. Such a

Radial patterns of bitumen dykes around Quaternary volcanoes, provinces of northern Neuquén and southernmost Mendoza, Argentina

NASA Astrophysics Data System (ADS)

Cobbold, Peter R.; Ruffet, Gilles; Leith, Leslie; Loseth, Helge; Rodrigues, Nuno; Leanza, Hector A.; Zanella, Alain

2014-12-01

Where the Neuquén Basin of Argentina abuts the Andes, hundreds of veins of solid hydrocarbon (bitumen) are visible at the surface. Many of these veins became mines, especially in the last century. By consensus, the bitumen has resulted from maturation of organic-rich shales, especially the Vaca Muerta Fm of Late Jurassic age, but also the Agrio Fm of Early Cretaceous age. To account for their maturation, recent authors have invoked regional subsidence, whereas early geologists invoked magmatic activity. During 12 field seasons (since 1998), we have tracked down the bitumen localities, mapped the veins and host rocks, sampled them, studied their compositions, and dated some of them. In the provinces of northern Neuquén and southernmost Mendoza, the bitumen veins are mostly sub-vertical dykes. They tend to be straight and continuous, crosscutting regional structures and strata of all ages, from Jurassic to Palaeocene. Most of the localities lie within 70 km of Tromen volcano, although four are along the Rio Colorado fault zone and another two are at the base of Auca Mahuida volcano. On both volcanic edifices, lavas are of late Pliocene to Pleistocene age. Although regionally many of the bitumen dykes tend to track the current direction of maximum horizontal tectonic stress (ENE), others do not. However, most of the dykes radiate outward from the volcanoes, especially Tromen. Thicknesses of dykes tend to be greatest close to Tromen and where the host rocks are the most resistant to fracturing. Many of the dykes occur in the exhumed hanging walls of deep thrusts, especially at the foot of Tromen. Here the bitumen is in places of high grade (impsonite), whereas further out it tends to be of medium grade (grahamite). A few bitumen dykes contain fragments of Vaca Muerta shale, so that we infer forceful expulsion of source rock. At Curacó Mine, some shale fragments contain bedding-parallel veins of fibrous calcite (beef) and these contain some bitumen, which is

11. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

11. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 INTERIOR DETAIL OF FRAME CONSTRUCTION - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

Pesticides in soil and sediment of a dyke-protected area of the Red River Delta, Vietnam

NASA Astrophysics Data System (ADS)

Braun, Gianna; Bläsing, Melanie; Kruse, Jens; Amelung, Wulf; Renaud, Fabrice; Sebesvari, Zita

2017-04-01

Coastal regions are densely populated but at the same time represent important agricultural areas for food production of the growing world population. To sustain high agricultural yields, in monocultures such as permanent rice systems, pesticides are used in high quantity and frequency. While earlier studies monitored the fate of pesticides in paddy rice systems, the overall fate of these compounds is altered nowadays due to the construction of dykes, which are needed in many delta regions to protect them from high tides, storm surges and salt water intrusion such as in the Red River Delta. The dyke system regulates the discharge and water exchange inside the diked area including irrigation channels for the paddy rice production. Local authorities observed increasing pollution towards the sea (highest pollution close to the dykes) and hypothesized that the dyke system would prevent water exchange and thus lead to an accumulation of pollutants within the diked area. Hence, the purpose of this study was to investigate the effect of dykes on pesticide pollution patterns in coastal delta regions of the Red River Delta. The study was conducted in the district Giao Thuy of the Red River Delta, Vietnam. This area is surrounded by a sea and river dyke; both have several inlet and outlet gates to control the water level in the irrigation channels. We determined the pesticide pollution pattern in a diked agricultural area, as well as along salinity gradients in and outside the diked areas. Samples were taken from rice fields and sediments from irrigation channels inside the diked area as well from saline aquaculture fields located outside the dyke. Pesticide analysis was conducted by accelerated solvent extraction (ASE), followed up by the clean-up process described by Laabs et al. (2007) and analyses using gas chromatography coupled with a mass selective detector (MSD). Preliminary results suggest that out of the 26 analysed compounds chlorpyrifos, propiconazole and

Microstructural indicators of convection in sills and dykes

NASA Astrophysics Data System (ADS)

Holness, Marian; Neufeld, Jerome; Gilbert, Andrew

2016-04-01

. In mafic sills, the average apparent aspect ratio (AR), as measured in thin-section, varies smoothly with model crystallization times (calculated assuming diffusive heat loss), consistent with in situ growth in solidification fronts. However, AR is invariant across individual mafic dykes, with decreasing values (i.e. more blocky grains) as the dyke width increases. This difference can be accounted for by the plagioclase in dykes growing as individual grains and clusters suspended in a convecting magma. Cooling at a vertical wall, as is the case for dykes, will always result in a gravitational convective instability, and therefore crystal-poor magma in dykes will always convect. As solidification proceeds, the increasing volume fraction of suspended crystals will eventually damp convection: the final stages of solidification occur in static crystal-rich magma, containing a well-mixed grain population. That the Shiant Isles Main Sill exhibits evidence for prolonged convection of sufficient vigour to suspend 5 mm olivine clusters, while other sills of comparable thickness contain plagioclase with grain shapes indicative of growth predominantly in solidification fronts, is most likely due to the composite nature of the Shiant. The 140m unit is underlain by 23m of picrite which intruded shortly before - this heat source would have acted as a strong driver for convection.

Paleomagnetic Results of the 925 Ma Mafic Dykes From the North China Craton: Implications for the Neoproterozoic Paleogeography of Rodinia

NASA Astrophysics Data System (ADS)

Zhao, X.; Peng, P.

2017-12-01

Precambrian mafic dyke swarms are useful geologic records for Neoproterozoic paleogeographic reconstruction. We present a paleomagnetic study of the 925 Ma Dashigou dyke swarm from 3 widely separated locations in the central and northern parts of the North China Craton, which are previously unsampled regions. Stepwise thermal and alternating field demagnetizations were successful in isolating two magnetic components. The lower unblocking temperature component represents the recent Earth magnetic field. The higher unblocking temperature component is the characteristic remanent magnetization and yields positive baked contact test. Results from detailed rock magnetic measurements corroborate the demagnetization behavior and show that titanomagnetites are the main magnetic carrier in these rocks. There was no regional event that has reset the remanent magnetization of all the dyke sites, as indicated by the magnetization directions of both overlying and underlying strata. The similarity of the virtual paleomagnetic poles for the 3 sampled regions also argues that the characteristic remanent magnetizations are primary magnetization when the dykes were emplaced. The paleomagnetic poles from the Dashigou dyke swarm of the North China Craton are not similar to those of the identical aged Bahia dykes from the São Francisco Craton, Brazil, indicating that these mafic dykes may be not parts of a common regional magmatic event that affected North China Craton and NE Brazil at about 925 Ma.

Petrogenesis and tectonic association of rift-related basic Panjal dykes from the northern Indian plate, North-Western Pakistan: evidence of high-Ti basalts analogous to dykes from Tibet

NASA Astrophysics Data System (ADS)

Sajid, Muhammad; Andersen, Jens; Arif, Mohammad

2017-10-01

Rift related magmatism during Permian time in the northern margin of Indian plate is represented by basic dykes in several Himalayan terranes including north western Pakistan. The field relations, mineralogy and whole rock geochemistry of these basic dykes reveal significant textural, mineralogical and chemical variation between two major types (a) dolerite and (b) amphibolite. Intra-plate tectonic settings for both rock types have been interpreted on the basis of low Zr/Nb ratios (< 10), K/Ba ratios (20-40) and Hf-Ta-Th and FeO-MgO-Al2O3 discrimination diagrams. The compositional zoning in plagioclase and clinopyroxene, variation in olivine compositions and major elements oxide trends indicate a vital role of fractional crystallization in the evolution of dolerites, which also show depletion in rare earth elements (REEs) and other incompatible elements compared to the amphibolites. The equilibrium partial melting models from primitive mantle using Dy/Yb, La/Yb, Sm/Yb and La/Sm ratios show that amphibolite formed by smaller degrees (< 5%) of partial melting than the dolerites (< 10%). The trace elements ratios suggest the origination of dolerites from the subcontinental lithospheric mantle with some crustal contamination. This is consistent with a petrogenetic relationship with Panjal trap magmatism, reported from Kashmir and other parts of north western India. The amphibolites, in contrast, show affinity towards Ocean Island basalts (OIB) with a relatively deep asthenospheric mantle source and minimal crustal contribution and are geochemically similar to the High-Ti mafic dykes of southern Qiangtang, Tibet. These similarities combined with Permian tectonic restoration of Gondwana indicate the coeval origin for both dykes from distinct mantle source during continental rifting related to formation of the Neotethys Ocean.

Petrogenesis and tectonic association of rift-related basic Panjal dykes from the northern Indian plate, North-Western Pakistan: evidence of high-Ti basalts analogous to dykes from Tibet

NASA Astrophysics Data System (ADS)

Sajid, Muhammad; Andersen, Jens; Arif, Mohammad

2018-06-01

Rift related magmatism during Permian time in the northern margin of Indian plate is represented by basic dykes in several Himalayan terranes including north western Pakistan. The field relations, mineralogy and whole rock geochemistry of these basic dykes reveal significant textural, mineralogical and chemical variation between two major types (a) dolerite and (b) amphibolite. Intra-plate tectonic settings for both rock types have been interpreted on the basis of low Zr/Nb ratios (< 10), K/Ba ratios (20-40) and Hf-Ta-Th and FeO-MgO-Al2O3 discrimination diagrams. The compositional zoning in plagioclase and clinopyroxene, variation in olivine compositions and major elements oxide trends indicate a vital role of fractional crystallization in the evolution of dolerites, which also show depletion in rare earth elements (REEs) and other incompatible elements compared to the amphibolites. The equilibrium partial melting models from primitive mantle using Dy/Yb, La/Yb, Sm/Yb and La/Sm ratios show that amphibolite formed by smaller degrees (< 5%) of partial melting than the dolerites (< 10%). The trace elements ratios suggest the origination of dolerites from the subcontinental lithospheric mantle with some crustal contamination. This is consistent with a petrogenetic relationship with Panjal trap magmatism, reported from Kashmir and other parts of north western India. The amphibolites, in contrast, show affinity towards Ocean Island basalts (OIB) with a relatively deep asthenospheric mantle source and minimal crustal contribution and are geochemically similar to the High-Ti mafic dykes of southern Qiangtang, Tibet. These similarities combined with Permian tectonic restoration of Gondwana indicate the coeval origin for both dykes from distinct mantle source during continental rifting related to formation of the Neotethys Ocean.

Geodynamic Setting of Proterozoic Dyke Swarms of the Leo-Man Craton, West Africa, Based on New U-Pb Dating and Geochemistry

NASA Astrophysics Data System (ADS)

Baratoux, L.; Jessell, M.; Söderlund, U.; Ernst, R. E.; Benoit, M.; Naba, S.; Cournede, C.; Perrouty, S.; Metelka, V.; Yatte, D.; Diallo, D. P.; Ndiaye, P. M.; Dioh, E.; Baratoux, D.

2016-12-01

Over 20 sets of dolerite dykes crosscutting Paleoproterozoic basement in West Africa were distinguished via the interpretation of regional and high-resolution airborne magnetic data available over the West African Craton. Some of the dykes reach over 300 km in length and are considered parts of much larger systems of mafic dyke swarms which form the plumbing system of Large Igneous Provinces (LIPs). Five different dyke swarms in Burkina Faso, Niger, Ghana and Senegal were investigated. In terms of petrography and composition, the mafic dykes correspond to tholeiitic basalts and are typically composed of plagioclase + clinopyroxene ± orthopyroxene ± olivine. They display a doleritic texture of variable grain size. Eleven ID-TIMS U-Pb ages obtained on baddeleyite define five generations of Proterozoic age. The N10 Libiri dyke swarm, found in western Niger, yielded an age of ca. 1790 Ma. The N40 Bassari swarm in Senegal was dated at ca. 1764 Ma, and is potentially linked to the 1790 Ma Libiri swarm, 1400 km away. The 300 by 400 km Korsimoro N100 dyke swarm transects central Burkina Faso and was dated at ca. 1575 Ma. Five ca. 1520 Ma ages were obtained for dykes of the Essakane swarm, three in Burkina Faso, one from Ghana (N130 orientation) and one from Senegal (E-W orientation), and document a large extent (600 km wide and 1500 km long) and short duration of dyke emplacement. The Manso N350 dyke swarm in southern Ghana, which is about 400 km long and about 200 km wide, yields a preliminary age of ca 870 Ma. A mantle plume origin is suggested for these swarms, especially the 1790-1765 Ma Libiri-Bassari swarm and the 1520 Ma Essakane swarms (which have lithosphere-contaminated E-MORB chemistry), whose scale is similar to largest giant radiating swarms (e.g. CAMP and Mackenzie). The 870 Ma Manso swarm has composition closer to OIB, consistent with a plume/hotspot origin. The 1575 Ma Korsimoro swarm has composition between EMORB and NMORB, which suggests a rift setting.

8. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

8. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 BRICK NOGGING AND ORIGINAL WEATHERBOARDING OF SOUTH ELEVATION - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

Paleomagnetism and geochronological studies on a 450 km long 2216 Ma dyke from the Dharwar craton, southern India

NASA Astrophysics Data System (ADS)

Nagaraju, E.; Parashuramulu, V.; Kumar, Anil; Srinivas Sarma, D.

2018-01-01

Paleomagnetic and geochronological studies were carried out on a ∼ 450 km long (from 17 sites) N-S striking Paleoproterozoic dyke swarm exposed along a natural crustal cross section of about 10 km (increasing from North to South) in the Dharwar Craton, to study the characteristics of paleomagnetism and geochronology in vertical dimension. U-Pb/Pb-Pb dating on baddeleyite gives a crystallisation age of 2216.0 ± 0.9 Ma for long dyke AKLD. Paleomagnetic data from this well dated ∼ 2216 Ma dyke swarm in Dharwar Craton are of excellent quality. High coercivity and high blocking temperature components are carried by single domain magnetite and show dual polarity remanence directions. Combined normal and reverse polarity remanences on AKLD and other N-S dykes define the most reliable paleomagnetic pole for ∼ 2216 Ma at latitude 36°S and longitude 312°E (A95 = 7°). Though paleomagnetic data is unavailable on other N-S dykes below the Cuddapah basin, high precision geochronology suggest that they are of similar age within errors. Though there is a variation in the crustal depth of Dharwar craton from north to south, consistent Pb-Pb/U-Pb baddeleyite geochronology and paleomagnetic studies along the AKLD established its continuity and preservation along its entire strike length. The virtual geomagnetic poles of these sites confirm a stable remanence and are almost identical to the previously reported paleomagnetic pole and also supported by positive reversal test. Positive paleomagnetic reversal test on these dykes signify that the remanent magnetization is primary and formed during initial cooling of the intrusions. Updated apparent polar wander path of Dharwar craton indicates relatively low drift rate during 2.21-2.08 Ga interval. Magnetogranulometry and SEM studies show that remanent magnetization in this dyke was carried by single domain magnetite residing within silicate minerals.

Volcanic outcrops of southeast Ethiopia and the Ogaden Dyke Swarm

NASA Astrophysics Data System (ADS)

Mège, Daniel; Purcell, Peter; Jourdan, Fred; Pochat, Stéphane

2013-04-01

A new map of Tertiary volcanics occurrences in the Ogaden region of southeast Ethiopia and adjacent areas of Somalia has been prepared. Outcrop areas, mapped using satellite images and helicopter-­-supported field work in 2008, are more widespread than previously recognized, while magnetic and drill data reveal the vast subsurface extent of the magmatism. Several spectacular 'meandering' outcrops, over 100 km long, are undoubtedly exhumed canyon-­-filling flows and magnetic data show that many other apparently isolated outcrops are actually part of similar flows, the bulk of which are now subsurface. Age dating and well intersections show several volcanic episodes, with the major outpouring occurring across a broad peneplain in the Oligocene. Geological and aeromagnetic mapping, and 40Ar/39Ar age dating, reveal a dyke swarm extending SSE from the southern Afar margin more than 600 km across the Somali Plate, and coeval with dyke injection in the Red Sea rift at ~25 Ma. The Ogaden Dyke Swarm, which occurs in an area historically considered remote from the impact of the Afro-­-Arabian rifting and volcanism, appears associated with the Marda Fault and marks a zone of crustal dilation along the Red Sea trend across the Horn of Africa. Contemporaneous rifts, also trending WNW/ESE and over 120 km long, occur in NE Somalia, confirming the predominantly NE/SW-­-directed crustal stress regime in the Ogaden and adjacent region at this time.

An Integrated Geochronological, Petrological, Geochemical and Paleomagnetic Study of Paleoproterozoic and Mesoproterozoic Mafic Dyke Swarms in the Nain Craton, Labrador

NASA Astrophysics Data System (ADS)

Sahin, Tugce

The Nain craton comprises the western, Labrador segment of the larger North Atlantic craton (NAC) which exposes Early through Late Archean gneisses. The NAC is bounded on all sides by Paleoproterozoic collisional orogens that involved either considerable structural reworking (Torngat-Nagssugtoqidian-Lewisian) or the accretion of juvenile arc magmas (Ketilidian-Makkovik). The NAC remains poorly understood compared to other Archean crustal blocks now dispersed globally. Compounding this problem is a lack of reliable paleomagnetic poles for NAC units that predate its assembly into the supercontinent Laurentia by ca. 1800 Ma, which could be used to test neighboring relationships with other cratonic fragments. In order to understand the history of the NAC as part of a possible, larger supercontinent, the record of mafic dyke swarms affecting the craton, particularly those that postdate the Late Archean terrane assembly, were examined in this study. Diabase or gabbroic dyke swarms are invaluable in such studies because their geometries offer possible locus points, they often have a punctuated emplacement and precisely datable crystallization histories, and they have cooling histories and oxide mineralogy amenable to recovering robust paleopoles. Coastal Labrador exposes a number of mafic dykes, some of which are demonstrably Paleoproterozoic (e.g. 2235 Ma Kikkertavak dykes; 2121 Ma Tikkigatsiagak dykes) or Mesoproterozoic (e.g. 1280-1270 Ma Nain and Harp dykes) in age (U-Pb; baddeleyite or zircon). The southern half of the Nain craton (Hopedale block) in particular preserves a rich array of mafic dykes. Dyke cross-cutting relationships are numerous and relatively well exposed, permitting multiple opportunities for paleomagnetic field tests (e.g. baked contact). The results presented here allow understanding of the tectonic evolution of the NAC with implications for strengthened Labrador-Greenland correlations, and testing possible Paleoproterozoic supercontinent

Syn-convergence extension in the southern Lhasa terrane: Evidence from late Cretaceous adakitic granodiorite and coeval gabbroic-dioritic dykes

NASA Astrophysics Data System (ADS)

Ma, Xuxuan; Xu, Zhiqin; Meert, Joseph G.

2017-10-01

Late Cretaceous (∼100-80 Ma) magmatism in the Gangdese magmatic belt plays a pivotal role in understanding the evolutionary history and tectonic regime of the southern Lhasa terrane. The geodynamic process for the formation of the early Late Cretaceous magmatism has long been an issue of hot debates. Here, petrology, geochronology and geochemistry of early Late Cretaceous granodiorite and coeval gabbroic-dioritic dykes in the Caina region, southern Lhasa, were investigated in an effort to ascertain their petrogenesis, age of intrusion, magma mixing and tectonic setting. Zircon U-Pb dating of granodiorite yields 206Pb/238U ages of 85.8 ± 1.7 and 86.4 ± 1.1 Ma, whilst that of the E-W trending dykes yields ages of 82.7 ± 2.6 and 83.5 ± 3.5 Ma. Within error, the crystallization ages of the dykes and the granodiorite are indistinguishable. Field observations and mineralogical microstructures are suggestive of a magma mixing process during the formation of the dykes and the granodiorite. The granodiorite exhibits geochemical features that are in agreement with those of subduction-related high-SiO2 adakites. The granodiorite and dykes have relatively constant εNd(t) values of +2.2 to +4.9 and initial 87Sr/86Sr ratios (0.7045-0.7047). These similar characteristics are herein interpreted as an evolutionary series from the dykes to granodiorite, consistent with magma mixing process. Ti-in-zircon thermometer and Al-in-hornblende barometer indicate that the granodiorite and the dioritic dyke crystallized at temperatures of ca. 750 and 800 °C, depths of ca. 6-10 and 5-9 km, respectively. Taking into account the synchronous magmatic rocks in the Gangdese Belt and the coeval rifted basin within the Lhasa terrane, the granodiorite and dykes reveal an early Late Cretaceous syn-convergence extensional regime in the southern Lhasa terrane, triggered by slab rollback of the Neotethyan oceanic lithosphere.

Lamprophyres from the Harohalli dyke swarm in the Halaguru and Mysore areas, Southern India: Implications for backarc basin magmatism

NASA Astrophysics Data System (ADS)

Lanjewar, Shubhangi; Randive, Kirtikumar

2018-05-01

The Bangalore and Harohalli dyke swarms occur in the eastern part of the Dharwar craton. The older Bangalore dyke swarm is made up of dolerites, trending east-west, and the younger contains alkaline dykes that trend approximately north-south. The lamprophyres of the Harohalli dyke swarm occur in the Halaguru and Mysore industrial areas where they are exposed as fresh porphyritic - panidiomorphic dykes, containing crustal xenoliths, and showing chilled contacts with the country rock charnokites. They are chiefly composed of amphiboles which form well-developed phenocrysts. Clinopyroxenes are present in some of the dykes. Compositional zoning is observed in clinopyroxenes and amphiboles; their zoning patterns indicate that the magma experienced cryptic variations and that fractional crystallization was a dominant process in the evolution of the Harohalli Lamprophyres (HRL). The HRL are calc-alkaline with shoshonitic affinity and exhibit a K2O/Na2O ratio of ∼1. They show primitive (MORB-like) trace-element characters. LILE and LREE both show marginally enriched patterns; whereas HFSE and HREE show strongly depleted patterns. In the regional geologic sense, HRL dykes are characterised by two major influences; namely, (i) primary source region characteristics, which are geochemically more primitive, roughly falling within fields of primitive - MORB and enriched- MORB and (ii) the continental lithosphere. The data points for the HRL distinctly show their proximity to N-MORB and scatter towards the continental crust. Moreover, features like xenolith assimilation might influence the trace-element characteristics of the HRL dykes. Such magmas with mixed characters can be formed in a backarc basin environment. Geochemical proxies such as Ba/Nb vs Nb/Yb, Ba/Th vs Th/Nb, and the water content of magmas; which have been effectively used for discriminating backarc basin magmas worldwide, also indicate that the HRL magmas were generated in a backarc environment with inputs from

Paleomagnetism of the Grenville diabase dyke swarm and implications for the mid Vendian paleolatitude of Laurentia

NASA Astrophysics Data System (ADS)

Buchan, K. L.; Ernst, R. E.; Kumarapeli, P. S.

2004-05-01

The Vendian-early Cambrian drift of Laurentia is important for theories of `Snowball Earth' and the continental breakup that formed the Iapetus Ocean. However, estimates of Laurentia's paleolatitude in this period differ widely. Some authors have proposed that Laurentia remained in low latitude throughout this period, whereas others have supported rapid drift of the continent from low to high and back to low latitude. To assist in evaluating these models, a paleomagnetic study was conducted on the mid Vendian Grenville dyke swarm of southeastern Laurentia. This 700 km long swarm was emplaced along the Ottawa graben, an aulacogen associated with rifting that preceded the opening of the Iapetus Ocean. The swarm was the subject of an early paleomagnetic study by Murthy (1971). More recently, U-Pb baddeleyite and zircon ages of ca. 590 Ma have been described for three Grenville dykes (Kamo et al. 1995). At one of these sites, on the `Mattawa' dyke, a positive paleomagnetic baked contact test was also reported (Hyodo and Dunlop 1993). In that detailed test thermoremanent overprinting in the zone of hybrid magnetization was shown to match that expected from heat conduction for a cooling dyke. Nevertheless, Hyodo and Dunlop suggested that the steep down remanence in the dyke, although primary, was likely acquired during a geomagnetic excursion because it did not appear to fit the then-available polar wander path. In our study, paleomagnetic sampling was carried out at 36 sites, including all three dated locations. A detailed analysis has been completed for the dated sites and preliminary analysis for the remaining sites. A stable steep down remanence was obtained for all samples in the Mattawa dyke, and in most samples from a second dated site. The third dated site is less stably magnetized and has not yielded a usable remanence direction. Ten additional sites yield stable steep down or occasionally steep up remanences. The presence of a steep remanence in two dated dykes

Rethinking monogamy's nature: From the truth of non/monogamy to a dyke ethics of "antimonogamy".

PubMed

Willey, Angela

2018-04-03

Following Lynne Huffer's work on queer feminism, this abridged essay centers the figure of the lesbian in order to develop a dyke ethics that engenders nuanced thinking about both monogamy and embodiment. The essay reads Alison Bechdel's comic strip, Dykes to Watch Out For, to elaborate a "dyke ethics of anti-monogamy." Grounded in notions of friendship, community, and social justice, this ethics decenters the sexual dyad in a way that polyamory does not. It also insists upon a theoretical and ethical disposition of respect for the simultaneously political and embodied nature of desire. In so doing, it offers first a way of re-thinking the story of monogamy's nature as a naturecultural tale about mononormative desire and further places that desire in a field of relationality that renders its significance as a feature of humanness and an object of scientific inquiry strange.

The meaning and value of traditional occupational practice: a Karen woman's story of weaving in the United States.

PubMed

Smith, Yda J; Stephenson, Stephanie; Gibson-Satterthwaite, Michelle

2013-01-01

This case study sought to understand the meaning of restoring traditional weaving as an occupation among Karen women from Burma who now live in an urban city in the United States and to examine the impact of weaving on their daily lives in terms of identity, empowerment, social support, and opportunities for entrepreneurship. The story of one Karen woman, Paw Law Eh, is described. Her story exemplifies the negative consequences of restricted access to familiar and meaningful daily activities, or "occupations", the relationship between occupation and self-identity, how participation in valued occupations can enhance social networks, and the restorative effects that are possible when engagement in meaningful occupations are maintained or restored. Her story demonstrates that occupational therapists have the skills and opportunity to contribute significantly to the well-being of Karen women by supporting the restoration of the occupation of weaving.

Dyke emplacement in a Quaternary active volcano: the exposed swarm of Monte Somma-Vesuvio (Naples, Italy)

NASA Astrophysics Data System (ADS)

Marinoni, L. B.

2003-04-01

The Monte Somma-Vesuvius is a famous active stratovolcano located on the Bay of Naples (Italy). Unexpectedly, the intrusive complex of this volcano is poorly known. This work focuses on the moderate-intensity dyke swarm that crops out along the caldera wall cut in the Monte Somma (MS) and its host rock. A detailed field survey of 101 individual intrusions consisted of the recording of about 20 parameters for each intrusion according to a standardised method. The intrusions were located in the framework of a new geological map drawn for the caldera wall at a scale 1:2000. The MS intrusions that crop out from 780 to 1055 m a.s.l., are mostly monogenetic steeply-dipping segmented dykes; inclined sheets are also present, generally dipping towards the outer periphery of the volcano. Apparent crosscut due to dyke segmentation is common; true intersections show ambiguous alternation of dyke strikes. Indicators of initial intrusive flow (opening stage of the dyke-hosting fracture) often differ in direction and sense from late-stage indicators. Frequently, dykes intruded sub-horizontally in an early stage and later sub-vertically. The peak extension for MS, computed according to a standardised method, is 81.7 m in the direction N90°, based on 96 exposed sheets. Very likely, most of MS sheets intruded within ~12 ka, giving a time-averaged minimum extension rate of ~7 mm a-1. On MS, the azimuth pattern and the azimuth of peak extension are different in the two portions in which the caldera wall can be divided, east and west of Canale dell'Arena. This difference may indicate that two fault systems affecting the basement underneath the volcano exert their influence on the feeding system. On the other hand, three main dyke sets (among which the set trending NE-SW is prevalent) exist on MS, and inclined sheets form a significant portion of the intrusions. In addition, the peak extension and the percentage extension are comparable quantitatively in the two different sections of

Structural, Geochemical, and Isotopic Studies on Magmatic Dyke Swarms of the South Shetland Islands Volcanic Arc, West Antarctica - Revealing the Geodynamic History

NASA Astrophysics Data System (ADS)

Kraus, S.; Miller, H.

2003-12-01

Between 2000 and 2002 areas of up to 100,000 m2 have been mapped at several locations of the South Shetland Islands, mainly on King George and Livingston Islands. A structural analysis of the dykes and the host rocks was undertaken, and about 250 dykes were sampled for geochemical studies. On Livingston Island six different strike directions were identified, yielding a reliable relative time sequence as deduced from field-relationships. Geochemically, these dykes can be separated into five different groups, correlating with the different strike directions, one of those groups comprising two directions. Analysis of the structural data shows, that at least on Livingston Island only minor changes of the tensional situation occurred. Geochemical data reveal that all dykes of the South Shetland Islands belong to a calc-alkaline, arc-related suite, ranging from primitive basalts to highly differentiated rhyolites. Interpretation of Sr isotopic data of the dykes proves difficult, as there are indications for sea-water induced Sr-alteration. Nd isotopic analysis yield better results, revealing a three-stage development from the oldest dykes (ɛ Nd -0.2 to 0.6) on Livingston Island towards a second, younger group (ɛ Nd 2.8 to 4.2, also Livingston), terminating with a third one (ɛ Nd 5.2 to 7.6), which includes the youngest dykes on Livingston and all dykes on King George and also Penguin Island. Either two mantle sources were involved, or the amount of crustal contamination changed considerately with time. It may have been high during initial arc volcanism, because of a still unstretched crust, then decreasing continually with progressing volcanism. In any case, the pattern reflects a chronological sequence corresponding with other authors' hypothesis of a migrating arc volcanism from SW to NE, i.e. from Livingston (older dykes) towards King George Island (younger dykes). Pb isotopic data, plottet together with MORB- and sediment-samples dredged from the Drake Passage

"I'm Telling You ... The Language Barrier Is the Most, the Biggest Challenge": Barriers to Education among Karen Refugee Women in Australia

ERIC Educational Resources Information Center

Watkins, Paula G.; Razee, Husna; Richters, Juliet

2012-01-01

This article examines factors influencing English language education, participation and achievement among Karen refugee women in Australia. Data were drawn from ethnographic observations and interviews with 67 participants between 2009 and 2011, collected as part of a larger qualitative study exploring the well-being of Karen refugee women in…

An Education Rooted in Two Worlds: The Karen of Northern Thailand

ERIC Educational Resources Information Center

Odochao, Jonni; Nakashima, Douglas; Vaddhanaphuti, Chayan

2006-01-01

In Karen culture, the family is traditionally the basic unit for the education of the child. In the early 1970s, when Jonni Odochao began to notice that children could not relate to their elders or respect them, he surmised that the problem stemmed from the modern education system and its increasing influence upon youth values, behaviour and ways…

Sandstone dykes in siwalik sandstone-sedimentology and basin analysis-subansiri district (NEFA), Eastern Himalaya

NASA Astrophysics Data System (ADS)

Kumar, Surendar; Singh, Trilochan

1982-11-01

Sandstone dykes (including sills) of varied thickness and with tapering ends are present either transecting or (sills) parallel to bedding in the Siwalik sandstone of Arunachal Pradesh (NEFA), Eastern Himalaya. The different sedimentary and microstructural analyses show varied conditions of deposition with changing facies from fluvial channel, to alluvial fan, to coastal plain-fan delta. The non-marine and shallow marine environments are indicated by the presence of organised and disorganised gradation and the presence of sandstone dykes in the interface regions. The orientations of the longer axes of the conglomerate along with the sand bedding indicate palaeoflow.

Does Deccan Volcanic Sequence contain more reversals than the three-Chron N-R-N flow magnetostratigraphy?- A paleomagnetic evidence from the dyke-swarm near Mumbai

NASA Astrophysics Data System (ADS)

Basavaiah, N.; Satyanarayana, KVV; Deenadayalan, K.; Prasad, JN

2018-02-01

New paleomagnetic data from a series of Deccan-age dykes cutting across the basement of lava flows along east and south of Mumbai (18°-19° N and 72°-73.5° E) have uncovered both normal (N) and reverse (R) magnetizations. Out of 33 dykes investigated, 29 dykes have yielded stable characteristic remanent magnetizations (ChRM) amenable for statistical analysis. Twenty dykes exhibit N-polarity and nine dykes show R-polarity. The tilt-corrected dyke VGPs reveal two distinct groups of dykes. Each group consists of both N- and R- polarity dykes on the Indian Apparent Polar Wander Path (APWP). The mean of N-polarity dykes is antipodal to the mean of R-polarity dykes. Group I (GI) comprises nine N-polarity dykes with their mean at Dm = 337.8°, Im = -39.4° (k = 130.7, α95 = 4.5°), and three dykes of R-polarity whose mean is at Dm = 150.7°, Im = 44.1° (k = 147.1, α95 = 10.2°). The corresponding pole positions are at 43.5° S, 102.6° E (A95 = 4.6°) and 36.6° S, 107.6° E (A95 = 8.9°) respectively. These pole positions fall close to 65 Ma old Deccan Superpole (DSP) on the APWP, and may therefore be associated with magnetic Chron 29 N for the N-polarity and 29R for the R-polarity of the three-Chron (30N - 29R -29Ν) magnetostratigraphy of the Deccan Volcanic Province (DVP) used in the computation of DSP. In Group II (GII), eleven dykes display N-polarity with mean at Dm = 312.6°, Im = -45.2° (k = 93.3, α95 = 4.8°) and six dykes show R-polarity with mean at Dm = 130.1°, Im = 48.0° (k = 176.8, α95 = 5.1°). The corresponding pole positions at 25° S, 120.1° E (A95 = 5.3°) and 22.2° S, 119.1° E (A95 = 5.2°) respectively are significantly displaced (by more than 20°) from the DSP along the older segment (˜80 -90 Ma) of the Indian APWP. Hence, the dykes of GII appear to have been emplaced in an earlier episodic Deccan activity than that represented by the DSP. The paleolatituides corresponding to GI and GII are 23.2° S ± 4.0 and 27.6° S ± 4

Crossed cerebro-cerebellar atrophy with Dyke Davidoff Masson syndrome.

PubMed

Algahtani, Hussein A; Aldarmahi, Ahmed A; Al-Rabia, Mohammed W; Young, G Bryan

2014-01-01

Dyke Davidoff Masson syndrome (DDMS) refers to atrophy or hypoplasia of one cerebral hemisphere following a prior fetal or childhood insult. It has characteristics of clinical and radiological changes. These changes include hemiparesis, seizures, facial-asymmetry, and mental retardation. We present a 25-year-old man with crossed cerebrocerebellar atrophy and DDMS. His seizures were well controlled using a combination of antiepileptic drugs.

Cardiovascular Disease–related Health Beliefs and Lifestyle Issues Among Karen Refugees Resettled in the United States From the Thai-Myanmar (Burma) Border

PubMed Central

Sin, Kai; Pye, Mu; Meng, Hsien-Wen

2017-01-01

Objectives Refugees resettled in the US may be at risk for cardiovascular disease (CVD). However, little is known about CVD-related issues among Karen refugees who have migrated to the US from the Thai-Myanmar border. The purpose of this study was to examine CVD-related health beliefs and lifestyle issues among Karen refugees resettled in the US. Methods Karen refugees resettled in the US from the Thai-Myanmar border (n=195) participated in a survey study on health beliefs related to CVD, salt intake, physical activity (PA), and smoking in the fall of 2016. Results A high-salt diet, physical inactivity, and smoking were major lifestyle problems. Participants who adhered to a low-salt diet considered themselves to be susceptible to CVD. Most participants did not engage in regular PA. Regular PA was associated with less perceived susceptibility to CVD and greater perceived benefits of a healthy lifestyle for decreasing the likelihood of CVD. Conclusions Each refugee population may require individualized strategies to promote PA and a healthy diet. Future studies should develop health education programs that are specifically designed for Karen refugees and evaluate such programs. In addition to health education programs on healthy lifestyle choices, tobacco cessation programs seem to be necessary for Karen refugees. At the same time, it is important to foster strategies to increase the utilization of preventive care among this population by promoting free or reduced-fee resources in the community to further promote their health. PMID:29207451

Does Deccan Volcanic Sequence contain more reversals than the three-Chron N-R-N flow magnetostratigraphy?—a palaeomagnetic evidence from the dyke-swarm near Mumbai

NASA Astrophysics Data System (ADS)

Basavaiah, N.; Satyanarayana, K. VV; Deenadayalan, K.; Prasad, J. N.

2018-06-01

New palaeomagnetic data from a series of Deccan-age dykes cutting across the basement of lava flows along east and south of Mumbai (18°-19°N and 72°-73.5°E) have uncovered both normal (N) and reverse (R) magnetizations. Out of 33 dykes investigated, 29 dykes have yielded stable characteristic remanent magnetizations (ChRM) amenable for statistical analysis. Twenty dykes exhibit N-polarity and nine dykes show R-polarity. The tilt-corrected dyke virtual geomagnetic poles reveal two distinct groups of dykes. Each group consists of both N- and R-polarity dykes on the Indian apparent polar wander path (APWP). The mean of N-polarity dykes is antipodal to the mean of R-polarity dykes. Group I (GI) comprises nine N-polarity dykes with their mean at Dm = 337.8°, Im = -39.4° (k = 130.7, α95 = 4.5°), and three dykes of R-polarity whose mean is at Dm = 150.7°, Im = 44.1° (k = 147.1, α95 = 10.2°). The corresponding pole positions are at 43.5°S, 102.6°E (A95 = 4.6°) and 36.6°S, 107.6°E (A95 = 8.9°) respectively. These pole positions fall close to 65 Ma old Deccan Superpole (DSP) on the APWP, and may therefore be associated with magnetic Chron 29N for the N-polarity and 29R for the R-polarity of the three-Chron (30N-29R-29Ν) magnetostratigraphy of the Deccan Volcanic Province (DVP) used in the computation of DSP. In Group II (GII), eleven dykes display N-polarity with mean at Dm = 312.6°, Im = -45.2° (k = 93.3, α95 = 4.8°) and six dykes show R-polarity with mean at Dm = 130.1°, Im = 48.0° (k = 176.8, α95 = 5.1°). The corresponding pole positions at 25°S, 120.1°E (A95 = 5.3°) and 22.2°S, 119.1°E (A95 = 5.2°) respectively are significantly displaced (by more than 20°) from the DSP along the older segment (˜80-90 Ma) of the Indian APWP. Hence, the dykes of GII appear to have been emplaced in an earlier episodic Deccan activity than that represented by the DSP. The palaeolatituides corresponding to GI and GII are 23.2°S ± 4.0 and 27.6°S ± 4

[Karen Blixen and her physicians].

PubMed

Søgaard, Ib

2002-01-01

In March 1941, two months after her wedding, Karen Blixen was diagnosed as having syphilis in the second stage. She was treated initially with mercury and later on in Denmark with salvarsan. Years later she received more treatment with mercury, salvarsan and bismuth, but in fact she was cured already in 1915 and told so by her venerologist Carl Rasch. However, she did not believe him, and several physicians, including well-known specialists in internal medicine and neurology told her many years later that she had to accept the diagnosis tabes dorsalis, i.e., syphilis in the third chronic stage. This paper claims, based on her medical records from several hospitals, that her physicians' attitude resulted in the delay of right treatment for her real disease for many years and led to at least one unwarrented surgical procedure (chordotomy). In 1956 she finally received surgical treatment of her stomach ulcer which for many years had caused her attacks of abdominal pain. The procedure was delayed for ten years because of a lumbar sympathectomy, which removes the pain for some years but not the ulcer itself, nor the bout of vomiting. Many doctors (and biographers) have been puzzled by her life-long bowel symptoms. It was often called tropic dysentery, in spite of the fact that this diagnosis was never confirmed by stool analyses. Instead it is suggested that most likely the Baroness caused the symptoms. She misused strong laxatives during her whole adult life. She did not tell her doctors about this until very late in her life and then it was far too late. Many times barium enemas showed a severe chronic condition with dehaustration and dilatation. The reason for her misuse was the fact that she was afraid of gaining too much weight. She used amphetamine during her life in Denmark after her return in 1931 in order to reduce her appetite, and probably she used Chat in Africa. She also constantly smoked cigarettes which in combination with minimal food intake facilitated

Early Jurassic mafic dykes from the Aigao uranium ore deposit in South China: Geochronology, petrogenesis and relationship with uranium mineralization

NASA Astrophysics Data System (ADS)

Zhang, Di; Zhao, Kui-Dong; Chen, Wei; Jiang, Shao-Yong

2018-05-01

Mafic dykes are abundant and widely distributed in many granite-hosted uranium ore deposits in South China. However, their geochronology, petrogenesis and relationship with uranium mineralization were poorly constrained. In this study, apatite U-Pb dating, whole-rock major and trace element and Sr-Nd-Pb isotope analysis were conducted for the dolerite dykes from the Aigao uranium ore deposit. Apatite U-Pb isotopic data indicate that the mafic dykes were emplaced at Early Jurassic (189 ± 4 Ma), which provides new evidence for the rarely identified Early Jurassic magmatism in South China. Pyroxene from the dykes is mainly augite, and plagioclase belongs to albite. The dolerite samples have relatively low SiO2 contents (45.33-46.79 wt%), relatively high total alkali contents (K2O + Na2O = 4.11-4.58 wt%) and Al2O3 contents (13.39-13.80 wt%), and medium MgO contents (4.29-5.16 wt%). They are enriched in Nb, Ta, Ti, rare earth elements and depleted in Rb, K, Sr, Th, showing the typical OIB-like geochemical affinity. All the dolerite samples show homogeneous Sr-Nd-Pb isotopic compositions, with (87Sr/86Sr)i varying from 0.706049 to 0.707137, εNd(t) from +4.6 to +5.2, 206Pb/204Pb from 19.032 to 19.126 and 207Pb/204Pb from 15.641 to 15.653. The mafic dykes in the Aigao deposit should be derived from the partial melting of the asthenospheric mantle and formed in a within-plate extensional environment. The emplacement age of the mafic dykes is older than the uranium mineralization age. Therefore, CO2 in ore-forming fluids couldn't originate from the basaltic magma as suggested by previous studies. The dolerite dykes might only provide a favorable reducing environment to promote the precipitation of uraninite from oxidize hydrothermal fluids.

Impacts of dyke development in flood prone areas in the Vietnamese Mekong Delta to downstream flood hazard

NASA Astrophysics Data System (ADS)

Khanh Triet Nguyen, Van; Dung Nguyen, Viet; Fujii, Hideto; Kummu, Matti; Merz, Bruno; Apel, Heiko

2017-04-01

Flooding in the Mekong Delta is an annual phenomenon causing inundation of large parts of the delta. This flooding is vital for the geomorphological stability of the delta, but is also the backbone of the highly productive agro-economy. However, extraordinary high floods are on the other hand a major hazard for the millions of people living in the delta. Therefore large scale developments of hydraulic structures took place in the Vietnamese part of the delta in the last decades. Particularly in the areas prone to deep and long lasting inundations many flood protection structures, mainly dykes, were built. These structures enable a blocking of inundation in large parts of these areas and by this the cropping of a third crop per year during the flood season. However, these structures are frequently blamed for increasing water levels in the areas downstream. Thus this study aimed at the investigation and attribution of changes in flood hazard in the Vietnamese Mekong Delta (VMD) due to high-dyke construction in deep flood prone areas, mainly in An Giang and Dong Thap provinces. This analysis started with the estimation of monotonic trends at key gauging stations in the delta: Kratie at the apex of the Mekong delta; Tan Chau and Chau Doc in the VMD just upstream of the areas with high-dyke construction; and Can Tho and My Thuan, located downstream of the high-dyke areas. The tests were undertaken assuming different magnitudes of errors in the data using historical records from 1978 - 2015, using the Mann-Kendall test and Sen's slope estimation. The obtained trends were thus tested for robustness against data errors. In order to obtain a better understanding of trends in the flood dynamics, the tests are performed on both flood peak and flood duration. In addition, the Pettitt test was applied to identify step changes in the water level data at 4 gauge stations located in the VMD. After the trend analysis, the impacts of high-dyke development were quantified with the

Les dykes basiques du massif ancien de l'Ourika (Atlas de Marrakech, Maroc): géochimie et significationThe basic dykes of the Ourika old massif (High Atlas of Marrakech): Geochemistry and significance

NASA Astrophysics Data System (ADS)

Barakat, Ahmed; Marignac, Christian; Bouabdelli, Mohamed

The Precambrian massif of Ourika is crosscut by two systems of basic dykes, striking N40°E and N90-120°E. Using incompatible trace elements, the two systems form two distinct chemical groups, displaying a continental tholeiitic affinity. The composition variations between the two defined groups can be due to heterogeneities of mantle sources and to contamination, during the magma ascent, by the continental crust. The emplacement of these basic dykes, before the late-PIII formations, can be related to the Neoproterozoic distension generalised to the Anti-Atlas chain. To cite this article: A. Barakat et al., C. R. Geoscience 334 (2002) 827-833.

Preliminary Geochemical Data for the Diabase Dykes from the Izmir-Ankara-Erzincan Suture Belt, Central Anatolia

NASA Astrophysics Data System (ADS)

Balcı, Uǧur; Sayıt, Kaan

2017-04-01

The Izmir-Ankara-Erzincan Suture Belt preserves oceanic and continental fragments originated from the closure of the northern branch of Neotethys. In the Bogazkale area (Central Anatolia), the pieces of the Neotethyan oceanic lithosphere exist in a chaotic manner, forming an ophiolitic mélange. Within the mélange, diabase dykes occur, which are found to cut various types of oceanic lithospheric rocks, including pillow basalts, gabbros and serpentinized ultramafics. We here present the preliminary geochemical results obtained from the diabase dykes and put some constraints on their petrogenesis. The investigated diabase dykes are chiefly composed of plagioclase and a mafic phase, which is clinopyroxene and/or hornblende. A detailed examination reveals two petrographic types on the basis of predominating mafic mineral phase, namely clinopyroxene-dominated Type 1, and hornblende-dominated Type 2. Ophitic to sub-ophitic textures, where lath-shaped plagioclase crystals are enclosed by clinopyroxene, can be observed in almost all Type 1 dykes. In Type 2 samples, altered mafic phases can be seen enclosed within plagioclase crystals, forming poikilitic texture. Polysynthetic twinning is common in plagioclase. Hornblende occasionally displays simple twinning. Both types appear to have been variably affected by low-grade hydrothermal alteration as reflected by the presence of secondary mineral phases, such as chlorite, epidote, prehnite, and actinolite. The whole-rock geochemistry appear to be consistent with the petrographical grouping, revealing distinct immobile trace element systematics for the two types. Both types have basaltic composition with sub-alkaline characteristics (Nb/Y=0.2-0.3 for Type 1; Nb/Y=0.02-0.08 for Type 2). The relatively low MgO contents of the dykes suggest that they do not represent primary magmas, but evolved through fractionation of mafic phases. In the N-MORB normalized diagrams, Type 2 diabases exhibit marked negative Nb anomalies, with HFSE

Magnetic resonance imaging depiction of acquired Dyke-Davidoff-Masson syndrome with crossed cerebro-cerebellar diaschisis: Report of two cases.

PubMed

Gupta, Ranjana; Joshi, Sandeep; Mittal, Amit; Luthra, Ishita; Mittal, Puneet; Verma, Vibha

2015-01-01

Acquired Dyke-Davidoff-Masson syndrome, also known as hemispheric atrophy, is characterized by loss of volume of one cerebral hemisphere from an insult in early life. Crossed cerebellar diaschisis refers to dysfunction/atrophy of cerebellar hemisphere which is secondary to contralateral supratentorial insult. We describe magnetic resonance imaging findings in two cases of acquired Dyke-Davidoff-Masson syndrome with crossed cerebro-cerebellar diaschisis.

Can we see the distal dyke communicate with the caldera? Examples of temporal correlation analysis using seismicity from the Bárðarbunga volcano

NASA Astrophysics Data System (ADS)

Jónsdóttir, Kristín; Jónasson, Kristján; Tumi Guðmundsson, Magnús; Hensch, Martin; Hooper, Andrew; Holohan, Eoghan; Sigmundsson, Freysteinn; Halldórsson, Sæmundur Ari; Vogfjörð, Kristín; Roberts, Matthew; Barsotti, Sara; Ófeigsson, Benedikt; Hjörleifsdóttir, Vala; Magnússon, Eyjólfur; Pálsson, Finnur; Parks, Michelle; Dumont, Stephanie; Einarsson, Páll; Guðmundsson, Gunnar

2016-04-01

The Bárðarbunga volcano is composed of a large oval caldera (7x11 km) and fissures extending tens of kilometers away from the caldera along the rift zone, which marks the divergent plate boundary across Iceland. On August 16th, 2014 an intense seismic swarm started below the Bárðarbunga caldera and in the two weeks that followed a dyke migrated some 47 km laterally in the uppermost 6-10 km of the crust along the rift. The dyke propagation terminated in lava fields just north of Vatnajökull glacier, where a major (1.5 km3) six months long eruption took place. Intense earthquake activity in the caldera started in the period August 21-24 with over 70 M5 earthquakes accompanying slow caldera collapse, as verified by various geodetic measurements. The subsidence is likely due to magma withdrawal from a reservoir at depth beneath the caldera. During a five months period, October-February, the seismic activity was separated by over 30 km in two clusters; one along the caldera rims (due to piecewise caldera subsidence) and the other at the far end of the dyke (as a result of small shear movements). Here we present statistical analysis comparing the temporal behaviour of seismicity recorded in the two clusters. By comparing the earthquake rate in the dyke in temporal bins before and after caldera subsidence earthquakes to the rate away from these bins (background rate), we show posing a statistical p-value test, that the number of dyke earthquakes was significantly higher (p <0.05) in the period 0-3 hours before a large earthquake (>M4.6) in the caldera. Increased dyke seismicity was also observed 0-3 hours following a large caldera earthquake. Elevated seismicity in the dyke before a large caldera earthquake may occur when a constriction in the dyke was reduced, followed by pressure drop in the chamber. Assuming that the large caldera earthquakes occurred when chamber pressure was lowest, the subsiding caldera piston may have caused temporary higher pressure in the

Ultramafic lavas and pyroxene-spinifex high-Mg basaltic dykes from the Othris ophiolite complex, Greece

NASA Astrophysics Data System (ADS)

Baziotis, Ioannis; Economou-Eliopoulos, Maria; Asimow, Paul

2017-04-01

This study aims to constrain the physico-chemical conditions and processes associated with the origin of ultramafic lavas of the Agrilia formation and high-Mg basaltic dykes in the Pournari area within the Othris ophiolite complex, a supra-subduction zone ophiolite of Mesozoic age (Paraskevopoulos & Economou, 1986; Barth et al., 2008). Hand-sample-scale spinifex texture is lacking from the ultramafic lavas and, despite whole-rock MgO contents greater than 31 wt.%, we infer an upper bound of 17 wt.% MgO for the erupted liquid, and thus identify these lavas as picrites containing accumulated olivine. We use textural and compositional criteria to divide the crystals within the Agrilia lavas between pre-eruptive and post-eruptive growth phases. The high-Mg basaltic dyke margins display a distinctive thin-section-scale micro-spinifex texture of skeletal and plumose Al- and Fe-rich clinopyroxene surrounded by large crystals of orthopyroxene. Normally zoned clinopyroxene in the Agrilia lavas and clinopyroxene of various textures (skeletal, needle- and dendritic-like) and sizes in the Pournari dykes display anomalous enrichment in Al2O3 and FeO* with decreasing MgO that require rapid, disequilibrium growth. Quantitative characteristics of the micro-spinifex pyroxene textures (<10 μm in width and 50-100 μm in length) imply a cooling rate for the marginal parts of the Pournari dykes of at least 25 °K/hr and more likely 45-55 °K/hr (Faure et al., 2004) and rapid growth of clinopyroxene crystals at a linear rate of about 10-6 m/s (Welsch et al., 2016). MELTS models of the crystallization sequence of the Pournari dykes indicate that progressive low-pressure (500 bar) fractional crystallization of the ultramafic dyke liquid occurred under oxidized (QFM+2.0) and hydrous (at least 0.5 wt.% H2O) conditions. A hydrous magmatic parent for the Othris ophiolite as a whole is further supported by preliminary investigation of melt inclusions (5-20 μm in diameter) in fresh chromite

Engaged Teaching and Learning with Adult Karen Refugees in a Service-Learning Site

ERIC Educational Resources Information Center

Smolen, Lynn Atkinson; Zhang, Wei; Detwiler, Stephen

2013-01-01

This article describes a case study of a service-learning project connected to a TESOL (teaching English to speakers of other languages) teacher preparation program. The case study explored the teacher candidates' experiences teaching English to Karen refugees from Myanmar (Burma) in a midwestern city in the United States. The teacher candidates'…

Meet Karen Dilka, Executive Director of the Council on Education of the Deaf

ERIC Educational Resources Information Center

Montgomery, Judy K.

2008-01-01

In April 2007, at the annual Council for Exceptional Children (CEC) Convention in Louisville, the author had the pleasure of meeting and then dining with Dr. Karen Dilka, executive director of the Council on Education of the Deaf (CED). Dilka also contributed as the on-site liaison and local arrangements chairperson for the Division for…

Long-period seismicity reveals magma pathways above a laterally propagating dyke during the 2014-15 Bárðarbunga rifting event, Iceland

NASA Astrophysics Data System (ADS)

Woods, Jennifer; Donaldson, Clare; White, Robert S.; Caudron, Corentin; Brandsdóttir, Bryndís; Hudson, Thomas S.; Ágústsdóttir, Thorbjörg

2018-05-01

The 2014-15 Bárðarbunga-Holuhraun rifting event comprised the best-monitored dyke intrusion to date and the largest eruption in Iceland in 230 years. A huge variety of seismicity was produced, including over 30,000 volcano-tectonic earthquakes (VTs) associated with the dyke propagation at ∼6 km depth below sea level, and large-magnitude earthquakes accompanying the collapse of Bárðarbunga caldera. We here study the long-period seismicity associated with the rifting event. We systematically detect and locate both long-period events (LPs) and tremor during the dyke propagation phase and the first week of the eruption. We identify clusters of highly similar, repetitive LPs, which have a peak frequency of ∼1 Hz and clear P and S phases followed by a long-duration coda. The source mechanisms are remarkably consistent between clusters and also fundamentally different to those of the VTs. We accurately locate LP clusters near each of three ice cauldrons (depressions formed by basal melting) that were observed on the surface of Dyngjujökull glacier above the path of the dyke. Most events are in the vicinity of the northernmost cauldron, at shallower depth than the VTs associated with lateral dyke propagation. At the two northerly cauldrons, periods of shallow seismic tremor following the clusters of LPs are also observed. Given that the LPs occur at ∼4 km depth and in swarms during times of dyke-stalling, we infer that they result from excitation of magmatic fluid-filled cavities and indicate magma ascent. We suggest that the tremor is the climax of the vertical melt movement, arising from either rapid, repeated excitation of the same LP cavities, or sub-glacial eruption processes. This long-period seismicity therefore represents magma pathways between the depth of the dyke-VT earthquakes and the surface. Notably, we do not detect tremor associated with each cauldron, despite melt reaching the base of the overlying ice cap, a concern for hazard monitoring.

Improvement of 2D ERT measurements conducted along a small earth-filled dyke using 3D topographic data and 3D computation of geometric factors

NASA Astrophysics Data System (ADS)

Bièvre, Grégory; Oxarango, Laurent; Günther, Thomas; Goutaland, David; Massardi, Michael

2018-06-01

In the framework of earth-filled dykes characterization and monitoring, Electrical Resistivity Tomography (ERT) turns out to be a commonly used method. 2D sections are generally acquired along the dyke crest thus putting forward the question of 3D artefacts in the inversion process. This paper proposes a methodology based on 3D direct numerical simulations of the ERT acquisition using a realistic topography of the study site. It allows computing ad hoc geometrical factors which can be used for the inversion of experimental ERT data. The method is first evaluated on a set of synthetic dyke configurations. Then, it is applied to experimental static and time-lapse ERT data set acquired before and after repair works carried out on a leaking zone of an earth-filled canal dyke in the centre of France. The computed geometric factors are lower than the analytic geometric factors in a range between -8% and - 18% for measurements conducted on the crest of the dyke. They exhibit a maximum under-estimation for intermediate electrode spacings in the Wenner and Schlumberger configurations. In the same way, for measurements conducted on the mid-slope of the dyke, the computed geometric factors are higher for short electrode spacings (+18%) and lower for lower for large electrode spacings (-8%). The 2D inversion of the synthetic data with these computed geometric factors provides a significant improvement of the agreement with the original resistivity. Two experimental profiles conducted on the same portion of the dyke but at different elevations also reveal a better agreement using this methodology. The comparison with apparent resistivity from EM31 profiling along the stretch of the dyke also supports this evidence. In the same way, some spurious effects which affected the time-lapse data were removed and improved the global readability of the time-lapse resistivity sections. The benefit on the structural interpretation of ERT images remains moderate but allows a better

Precise 40Ar/39Ar dating of basaltic dykes as an indicator of paleostress: exemple of the Icelandic rift jumps.

NASA Astrophysics Data System (ADS)

Arnaud, N. O.; Garcia, S.; Bergerat, F.

2003-04-01

Dykes constitute unique indicators of local paleostress. When compiled over a large area and over a significant time span they also underline larger changes in the global field stress and thus may be used together with the present day finite deformation to address global geodynamical problems. However, their use has often proved problematic because of their cryptic nature favouring excess argon retention or intake from the host rocks, as well as hydrothermal circulations and groundmass alteration. These flaws can be overtaken by careful sampling and specific sample preparation to get rid of “polluting” phases, reduction of the amount of used material using only hand picked glassy mesostasis, and replication of the analysis on several aliquots. This protocol allows to increase the number of significant results. In Iceland, rift zones have kept jumping for the past 20 Ma and probably even earlier as a response to the discontinuous capture of the mid-ocean ridge by the underlying Icelandic hotspot. However, direct determination of the age and location of paleorift zones has proven problematic because of rapid changes in the dipping of the lavas associated to overcasting of the oldest flows by younger ones, and also because of the retreat and discontinuity of flows associated with the severe glacial erosion. Dykes however do not suffer such problems and constitute excellent space/time indicators. About 65 dykes have systematically been dated on a 350 km long E-W cross section across the Northern Volcanic Zone, from the Vatnsnes peninsula to the east coast across the presently active Krafla rift. Excess argon proved to be rare, probably because of similar age and petrography between host rocks and intrusive dykes, although the basaltic dykes remain poor in potassium. Alteration of the groundmass was sometimes severe but replicate analysis usually helped in assessing a significant age. The final age distribution profile obtained from this important amount of data

Late Permian volcanic dykes in the crystalline basement of the Považský Inovec Mts. (Western Carpathians): U-Th-Pb zircon SHRIMP and monazite chemical dating

NASA Astrophysics Data System (ADS)

Pelech, Ondrej; Vozárová, Anna; Uher, Pavel; Petrík, Igor; Plašienka, Dušan; Šarinová, Katarína; Rodionov, Nikolay

2017-08-01

This paper presents geochronological data for the volcanic dykes located in the northern Považský Inovec Mts. The dykes are up to 5 m thick and tens to hundreds of metres long. They comprise variously inclined and oriented lenses, composed of strongly altered grey-green alkali basalts. Their age was variously interpreted and discussed in the past. Dykes were emplaced into the Tatricum metamorphic rocks, mostly consisting of mica schists and gneisses of the Variscan (early Carboniferous) age. Two different methods, zircon SHRIMP and monazite chemical dating, were applied to determine the age of these dykes. U-Pb SHRIMP dating of magmatic zircons yielded the concordia age of 260.2 ± 1.4 Ma. The Th-U-Pb monazite dating of the same dyke gave the CHIME age of 259 ± 3Ma. Both ages confirm the magmatic crystallization at the boundary of the latest Middle Permian to the Late Permian. Dyke emplacement was coeval with development of the Late Paleozoic sedimentary basin known in the northern Považský Inovec Mts. and could be correlated with other pre-Mesozoic Tethyan regions especially in the Southern Alps.

Dyke-Davidoff-Masson syndrome: case report of fetal unilateral ventriculomegaly and hypoplastic left middle cerebral artery.

PubMed

Piro, Ettore; Piccione, Maria; Marrone, Gianluca; Giuffrè, Mario; Corsello, Giovanni

2013-05-14

Prenatal ultrasonographic detection of unilateral cerebral ventriculomegaly arises suspicion of pathological condition related to cerebrospinal fluid flow obstruction or cerebral parenchimal pathology. Dyke-Davidoff-Masson syndrome is a rare condition characterized by cerebral hemiatrophy, calvarial thickening, skull and facial asymmetry, contralateral hemiparesis, cognitive impairment and seizures. Congenital and acquired types are recognized and have been described, mainly in late childhood, adolescence and adult ages. We describe a female infant with prenatal diagnosis of unilateral left ventriculomegaly in which early brain MRI and contrast enhanced-MRI angiography, showed cerebral left hemiatrophy associated with reduced caliber of the left middle cerebral artery revealing the characteristic findings of the Dyke-Davidoff-Masson syndrome. Prenatal imaging, cerebral vascular anomaly responsible for the cerebral hemiatrophy and the early clinical evolution have never been described before in such a young child and complete the acquired clinical descriptions in older children. Differential diagnosis, genetic investigations, neurophysiologic assessments, short term clinical and developmental follow up are described. Dyke-Davidoff-Masson syndrome must be ruled out in differential diagnosis of fetal unilateral ventriculomegaly. Early clinical assessment, differential diagnosis and cerebral imaging including cerebral MRI angiography allow the clinicians to diagnose also in early infancy this rare condition.

Extremely High Prevalence of Metronidazole-Resistant Helicobacter pylori Strains in Mountain People (Karen and Hmong) in Thailand

PubMed Central

Vilaichone, Ratha-korn; Ratanachu-ek, Thawee; Gamnarai, Pornpen; Chaithongrat, Supakarn; Uchida, Tomahisa; Yamaoka, Yoshio; Mahachai, Varocha

2016-01-01

This study aimed to survey the prevalence, patterns of antibiotic resistance, and clinical factors associated with antibiotic resistance in Helicobacter pylori among the Karen and Hmong mountain people of Thailand. We recruited dyspeptic patients in the Maesod district, Tak Province, Thailand. All subjects underwent upper gastrointestinal endoscopy, and three antral gastric biopsies were obtained for rapid urease tests and culture. An epsilometer was used to determine the minimum inhibitory concentrations of amoxicillin (AMX), clarithromycin (CLR), metronidazole (MNZ), levofloxacin (LVX), ciprofloxacin (CIP), and tetracycline (TET). A total of 291 subjects were enrolled; 149 (51.2%) were infected with H. pylori. Helicobacter pylori infection was present in 47.1% of Thai, 51.7% of Karen, and 58.7% of Hmong subjects. Antibiotic resistance was present in 75.8% including AMX (0.8%), TET (0%), CLR (5.6%), MNZ (71.8%), CIP (19.4%), LVX (19.4%), and multidrug resistance in 21.8%. Karen subjects had the highest prevalence of MNZ resistance (84.6%), and Hmong subjects had the highest prevalence of fluoroquinolone (27.3%) and multidrug (34.1%) resistance. MNZ plus fluoroquinolone (14.5%) was the most common multidrug resistance. There was no association between clinical factors and antibiotic resistance. MNZ resistance was prevalent, whereas fluoroquinolone- and multidrug-resistant H. pylori infections are important problems in mountain people of Thailand. PMID:26880772

A new 200 Ma paleomagnetic pole for Africa, and paleo-secular variation scatter from Central Atlantic Magmatic Province (CAMP) intrusives in Morocco (Ighrem and Foum Zguid dykes)

NASA Astrophysics Data System (ADS)

Palencia-Ortas, A.; Ruiz-Martínez, V. C.; Villalaín, J. J.; Osete, M. L.; Vegas, R.; Touil, A.; Hafid, A.; McIntosh, G.; van Hinsbergen, D. J. J.; Torsvik, T. H.

2011-06-01

Available apparent polar wander (APW) paths for the 200 Ma configuration of Pangea, just prior to the opening of the Central Atlantic Ocean, differ as much as 10o in arc length. Here, we add new data from northwest Africa for this time, obtained from the northeast-trending Foum-Zguid and Ighrem dykes (ca. 200 Ma). These dykes form part of the northern domain of the Central Atlantic Magmatic Province (CAMP), and crosscut the Anti-Atlas Ranges in Morocco, and compositionally correspond to quartz-normative tholeiites intruded in continental lithosphere shortly before the opening of the Central Atlantic Ocean. The Foum-Zguid dyke has been intensively studied, whereas the Ighrem dyke has received less scientific focus. We sampled both dykes for paleomagnetic investigation along 100 km of each dyke (12 sites for Foum-Zguid and 11 for Ighrem, 188 samples included in the final analyses). Rock magnetic experiments indicate a mixture of multidomain and single-domain magnetite and/or low-Ti titanomagnetite particles as the principal remanence carriers. In both dykes, the primary nature of the characteristic remanent magnetization is supported by positive contact tests, related to Fe-metasomatism or baked overprints of the corresponding sedimentary country rocks. The directions of the characteristic magnetization exhibit exclusively normal polarity. Site-mean virtual geomagnetic poles are differently grouped in each dyke, suggesting distinct geomagnetic secular variation records. The Foum-Zguid paleomagnetic pole (N= 12, PLat= 67.9°N, PLon= 247.9°E, κ= 125, A95= 3.9°) plots close to that of Ighrem (N= 11, PLat= 78.4°N, PLon= 238.2°E, κ= 47, A95= 6.7°), confirming those mineralogical and geochemical evidences supporting that they represent dissimilar magmatic stages. Virtual geomagnetic poles dispersion from both dykes (S= 10.5°13.0°8.1°) is in line with those obtained from recent studies of a CAMP-related dyke in Iberia and results from CAMP lavas in the Argana

Partners in a Great Adventure: Karen Bersche--Alliance Library System, East Peoria, IL

ERIC Educational Resources Information Center

Library Journal, 2005

2005-01-01

As early as junior high school, after she had gone to see The Music Man and came out idolizing Marian, Karen Bersche knew she was destined for librarianship. But she didn't get around to it until after she got a degree in counseling, started her family, and opened her own daycare center. She has more than made up for lost time since, first as…

Unbalanced Nature, Unbounded Bodies, and Unlimited Technology: Ecocriticism and Karen Traviss' Wess'har Series

ERIC Educational Resources Information Center

Sullivan, Heather I.

2010-01-01

While nature is often claimed to be a space of harmonized balance or an antidote to the chaos of the modern world, we need a more grounded assessment of nature as endlessly changing and much less predictable than we like to assume. In this essay, I explore Karen Traviss' provocative exploration of unbalanced nature and unbounded bodies in her…

The Karen Quinlan case: problems and proposals.

PubMed Central

Kennedy, I. M.

1976-01-01

Karen Quinlan, a young American girl, has lain in hospital since 15 April 1975 without any prospect of recovering consciousness. Her breathing is assisted by means of a respirator and she is fed through a tube inserted in her stomach. Her adoptive parents applied to the courts for permission for the respirator to be switched off. The judge refused permission. Using the Quinlan case as an exemplar, Mr. Kennedy analyses the medical points one by one against the legal background. He would like to see established a code of practice to assist doctors in such cases who at present have no legal guidance. A set of rules arising as a consequence of a series of court decisions would be undesirable; rather a code should be drawn up as the result of discussion between the many people concerned and the consensus so arrived at. PMID:957371

Palaeoproterozoic Indian shield in the global continental assembly: Evidence from the palaeomagnetism of mafic dyke swarms

NASA Astrophysics Data System (ADS)

Radhakrishna, T.; Krishnendu, N. R.; Balasubramonian, G.

2013-11-01

Palaeomagnetic study of Palaeoproterozoic mafic dykes in the basement along the margins of the Cuddapah basin, the largest Precambrian sedimentary basin in south India, is presented in detail for a general discussion of Palaeoproterozoic igneous activity in India. The results are compared with all earlier published data on mafic dykes in India and are integrated with recently-published high-precision U-Pb baddeleyite ages to provide a comprehensive account of Palaeoproterozoic igneous activity in India. The analysis consolidates palaeomagnetic poles for six age divisions between 2.45 and 1.85 Ga with robust statistical criteria. Our best estimates of overall mean poles from 241 dykes are situated at (1) λ = 17.7°N; Φ = 106.0°E (A95 = 9.0°; 7N = 24) at c. 2.45 Ga, (2) λ = 7.1°N; Φ = 57.2°E (A95 = 4.5°; N = 69) at c. 2.37 Ga, (3) λ = 41.6°S; Φ = 5.5°E (A95 = 5.1°; N = 34) at c. 2.22 Ga, (4) λ = 4.7°N; Φ = 343.0°E (A95 = 4.4°; N = 31) at 2.18 Ga, (5) λ = 49.2°N; Φ = 332.9°E (A95 = 4.8°; N = 24) at 1.99-1.89 Ga and (6) λ = 73.7°N; Φ = 282.6°E (A95 = 2.9°; N = 39) at 1.86 Ga. The data permit us to construct an apparent polar wander path for the Indian shield for an ~ 600 Ma interval of the Palaeoproterozoic eon (2.45-1.85 Ga). Testing and evaluation of continental reconstructions for this interval, which are mostly based on geological correlations, reveal many inconsistencies. Between 2.45 and 2.37 Ga, the Indian shield was situated at higher latitudes similar to the Yilgarn craton of Australia. It was subsequently located near the equator at 2.22, 2.18, 1.99 and 1.86 Ga. Thus, an India-Australia connection is supported during these times, but a proposed Australia-Kaapvaal link in "Zimvaalbara" and a Dharwar (India)-Slave connection in "Sclavia" or a Superior-Zimbabwe-India connection in "Superia" are inconsistent with Indian data. In addition, the close palaeomagnetic comparison between the Palaeoproterozoic dykes of Dharwar

Dykes and structures of the NE rift of Tenerife, Canary Islands: a record of stabilisation and destabilisation of ocean island rift zones

NASA Astrophysics Data System (ADS)

Delcamp, A.; Troll, V. R.; van Wyk de Vries, B.; Carracedo, J. C.; Petronis, M. S.; Pérez-Torrado, F. J.; Deegan, F. M.

2012-07-01

Many oceanic island rift zones are associated with lateral sector collapses, and several models have been proposed to explain this link. The North-East Rift Zone (NERZ) of Tenerife Island, Spain offers an opportunity to explore this relationship, as three successive collapses are located on both sides of the rift. We have carried out a systematic and detailed mapping campaign on the rift zone, including analysis of about 400 dykes. We recorded dyke morphology, thickness, composition, internal textural features and orientation to provide a catalogue of the characteristics of rift zone dykes. Dykes were intruded along the rift, but also radiate from several nodes along the rift and form en échelon sets along the walls of collapse scars. A striking characteristic of the dykes along the collapse scars is that they dip away from rift or embayment axes and are oblique to the collapse walls. This dyke pattern is consistent with the lateral spreading of the sectors long before the collapse events. The slump sides would create the necessary strike-slip movement to promote en échelon dyke patterns. The spreading flank would probably involve a basal decollement. Lateral flank spreading could have been generated by the intense intrusive activity along the rift but sectorial spreading in turn focused intrusive activity and allowed the development of deep intra-volcanic intrusive complexes. With continued magma supply, spreading caused temporary stabilisation of the rift by reducing slopes and relaxing stress. However, as magmatic intrusion persisted, a critical point was reached, beyond which further intrusion led to large-scale flank failure and sector collapse. During the early stages of growth, the rift could have been influenced by regional stress/strain fields and by pre-existing oceanic structures, but its later and mature development probably depended largely on the local volcanic and magmatic stress/strain fields that are effectively controlled by the rift zone growth

Elemental and Sr-Nd-Pb isotope geochemistry of the Florianópolis Dyke Swarm (Paraná Magmatic Province): crustal contamination and mantle source constraints

NASA Astrophysics Data System (ADS)

Marques, L. S.; De Min, A.; Rocha-Júnior, E. R. V.; Babinski, M.; Bellieni, G.; Figueiredo, A. M. G.

2018-04-01

The Florianópolis Dyke Swarm is located in Santa Catarina Island, comprising also the adjacent continental area, and belongs to the Paraná Magmatic Province (PMP). The dyke outcrops in the island are 0.1-70 m thick and most of them are coast-parallel (NE-SW trending), with subordinate NW-SE trending. The vast majority of the dykes has SiO2 varying from 50 to 55 wt% and relatively high-Ti (TiO2 > 3 wt%) contents and these rocks were divided using the criteria commonly used to distinguish the different magma-types identified in the volcanic rocks from the PMP. The Urubici dykes (Sr > 550 μg/g) are the most abundant and some of them experienced crustal contamination reaching to 10%, as evidenced by low P2O5/K2O (0.30-0.21), high (Rb/Ba)PM (1.0-2.2), and radiogenic Sr and Pb isotope compositions (87Sr/86Sri up to 0.70716 (back to 125 Ma) and 206Pb/204Pbm up to 19.093). The Pitanga (Sr < 550 μg/g) and the basaltic trachyandesite dykes are less abundant and almost all of them were also substantially affected by at least 15% of crustal assimilation, evidenced by high (Rb/Ba)PM (up to 2.6) and Sr (87Sr/86Sri = 0.70737-0.71758) and Pb (206Pb/204Pbm = 18.446-19.441) isotope ratios, as well as low P2O5/K2O values (0.30-0.18). The low-Ti (TiO2 < 2 wt%) dykes are scarce and show a large compositional variability (SiO2: 50.4-64.5 wt%), with similar geochemical characteristics of the low-Ti volcanic rocks (Gramado-Palmas) from southern PMP, although the most primitive dykes show hybrid characteristics of Ribeira and Esmeralda magmas. The presence of granitic xenoliths with border reactions and dykes with diffuse contacts indicate that crustal contamination probably occurred by assimilation from re-melted the host rocks. Considering only the high-Ti Urubici dykes that were not affected by crustal contamination, the Sr, Nd and Pb isotope mixing modelling indicates the participation of a heterogeneous metasomatized (refertilized) subcontinental lithospheric mantle (SCLM). This

InSAR Observations of the 2009 Harrat Lunayyir (western Saudi Arabia) Dyke Intrusion and Post-Diking Deformation

NASA Astrophysics Data System (ADS)

Jónsson, Sigurjón; Lu, Zhong; Lundgren, Paul

2010-05-01

Interferometric Satellite Radar (InSAR) observations of one of the volcanic provinces in western Saudi Arabia, Harrat Lunayyir (also known as Harrat Al-Shaqah), provide rich information about the geometry and evolution of a dyke intrusion and surface faulting that occurred in the region in April-July 2009. The first sign of activity was the start of a seismic swarm on 24 April that steadily intensified until six magnitude 4.6-5.7 earthquakes struck on 17-20 May. More than 30000 people were evacuated from the area following the activity in mid-May and stayed in the neighboring cities of Yanbu and Medina for several weeks. During the intensive activity in mid-May we sent a request for emergency satellite radar data acquisitions to the European Space Agency and later activated an International Charter to guarantee satellite data collection of the area. We have analyzed a number of Envisat, ALOS, and TerraSAR-X interferograms of the area and the results are outstanding, owing to the stable and vegetation-free surface conditions. Interferograms spanning the main seismic activity in mid-May exhibit strong deformation that extends across a large 40 km × 40 km area, with broad uplift and over a meter of WSW-ENE extension. In addition, the data show clear signs of surface faulting and graben-like subsidence in the middle of the deformed area with the graben subsidence exceeding 50 cm. Modeling of deformation strongly suggests that a near-vertical dyke intruded with a WNW-ESE orientation, parallel to the Red Sea, and that the intruded volume is ~0.13 km3. The dyke intrusion appears to have triggered faulting on graben-bounding and inward-dipping normal faults. The shallowest part of the dyke seems to have reached within only 2 km of the surface, right below where the graben is the narrowest and under an area with a number of cinder cones from previous volcanic events. While the day-to-day temporal evolution of the deformation cannot be derived from the InSAR data, the

A new classification system for lesbians: the Dyke Diagnostic Manual.

PubMed

Eliason, Michele J

2010-01-01

There has been a long-standing need for a diagnostic manual that documents the unique pathological behaviors of lesbians. The Dyke Diagnostic Manual (DDM) is meant to supplement mainstream classification systems used to identify problematic behaviors in heterosexuals. This article presents thirteen uniquely lesbian conditions that are nowhere to be found in heterosexist diagnostic systems. The DDM may help to reduce the pain and suffering found in many lesbian relationships where one or both partners are afflicted.

Interagency partnership to assess and restore a degraded urban riverine wetland: Dyke Marsh Wildlife Preserve, Virginia

USGS Publications Warehouse

Steury, Brent W.; Litwin, Ronald J.; Oberg, Erik T.; Smoot, Joseph P.; Pavich, Milan J.; Sanders, Geoffrey; Santucci, Vincent L.

2014-01-01

The narrow-leaved cattail wetland known as Dyke Marsh formally became a land holding of George Washington Memorial Parkway (GWMP, a unit of the national park system) in 1959, along with a congressional directive to honor a newly-let 30-year commercial sand and gravel dredge-mining lease at the site. Dredging continued until 1974 when Public Law 93-251 called for the National Park Service and the United States Army Corps of Engineers to “implement restoration of the historical and ecological values of Dyke Marsh.” By that time, about 83 acres of the marsh remained, and no congressional funding accompanied the passage of the law to effect any immediate conservation or restoration. Decades of dredge mining had severely altered the surface area of Dyke Marsh, the extent of its tidal creek system, and the shallow river bottom of the Potomac River abutting the marsh. Further, mining destabilized the marsh, causing persistent erosion, shoreline retreat, and tidal channel widening after mining ceased. Erosion has continued unchecked until the present; approximately 50 acres of the original marsh are now estimated to remain. The specific cause of persistent erosion had been unknown prior to this collaborative study but previously was assumed to be due to flooding by the Potomac River.

Absolute Geomagnetic Paleointensity as Recorded by Mafic Dykes of the ~1.98 Ga Bundelkhand Swarm and ~0.75 Ga Malani Igneous Suite from Northern India

NASA Astrophysics Data System (ADS)

Piispa, E. J.; Smirnov, A. V.; Pandit, M. K.

2012-12-01

Determining the long-term behavior and configuration of the Precambrian geomagnetic field is crucial for understanding the origin and nature of Earth's early geodynamo. However, our knowledge about strength and morphology of the Precambrian geomagnetic field is extremely limited due to paucity of reliable data on the ancient field strength (paleointensity). Information correlating the strength and characteristics of Earth's ancient geomagnetic field can be gained by measuring the paleodirectional and paleointensity properties of Precambrian rocks. We investigated two Proterozoic mafic dyke swarms from the Indian subcontinent: the extensive NW-SE trending 1979±8 Ma (U-Pb) dyke swarm in the Bundelkhand craton and the N-S trending Malani mafic dyke swarm, the latter representing the third and final phase of magmatism in the Malani Igneous Suite. Malani rhyolites have been precisely dated at 771±2 to 751±3 Ma (U - Pb zircon ages). The Malani mafic dykes have been correlated with the ~750 Ma dolerite dykes of Seychelles based on geological and geochemical criteria. The mafic dykes of both studied swarms are vertical to sub-vertical and show little or no evidence of alteration. Detailed paleomagnetic studies, using both thermal and alternating field demagnetization, revealed the presence of stable dual-polarity magnetic component for both dyke swarms. The primary nature of the magnetization is supported by positive baked contact tests. Typically, the characteristic magnetization is single component with narrow unblocking temperature spectra between ~500°C and 550-570°C, with remanence carried by small PSD magnetite or low-Ti titanomagnetite. Absolute paleointensities of these dyke swarms were obtained by two different heating based methods: multiple specimen domain-state corrected (MSP-DSC) and Thellier double heating method with alternating infield-zerofield (IZ) and zerofield-infield (ZI) steps. The multiple sample protocol incorporated checks for alteration

Formation and Origin of Metabreccia from the Parkin Offset Dyke at the Sudbury Impact Structure

NASA Astrophysics Data System (ADS)

Anders, D.; Osinski, G. R.; Grieve, R. A. F.; Péntek, A.

2015-09-01

Metabreccia is an important litholgy of the Offset Dykes of the Sudbury impact structure, however, its formation and origin is still topic of discussion. Here we present evidence that Metabreccia is a metamorphosed Footwall Breccia.

Temporal correlation between dyke swarms and crustal extension in the middle Palaeozoic Vilyui rift basin, Siberian platform

NASA Astrophysics Data System (ADS)

Polyansky, Oleg P.; Prokopiev, Andrei V.; Koroleva, Olga V.; Tomshin, Mikhail D.; Reverdatto, Vladimir V.; Selyatitsky, Alexander Yu.; Travin, Alexei V.; Vasiliev, Dmitry A.

2017-06-01

This paper presents results from new 40Ar/39Ar isotope dating of nine mafic dykes from three large dyke swarms (Vilyui-Markha, Kontai-Dzherba, and Chara-Sinsk) of the Yakutsk-Vilyui large igneous province (LIP), in addition to a reconstruction of the subsidence history of the middle Palaeozoic Vilyui paleorift basin (eastern Siberian platform). All previously published 40Ar/39Ar and U-Pb dates are summarized. Statistical analysis of the dyke ages reveals repeated magmatic events in the study area. Two major pulses of mafic magmatism are identified: one at the Frasnian-Famennian boundary, with a main peak at ca. 374.1 Ma, and another in the latest Devonian with a peak at ca. 363.4 Ma. The time of maximum intensity of dyke intrusion coincides (within uncertainty) with rapid subsidence in the Vilyui basin. The minimum total volume of middle Palaeozoic magmatism produced in the Yakutsk-Vilyui LIP is 100-215 K km3, which is much less than earlier estimates. Most of the mafic material within the Yakutsk-Vilyui LIP is related to the Vilyui basin and associated dyke swarms. Backstripping analysis of sedimentation in depressions of the Vilyui basin was carried out. Estimates were obtained for the spatial distribution of the stretching factor of the crust and mantle lithosphere, averaging 1.17 and 1.44, respectively. The amount of extension due to dyke intrusion is estimated to be 6%. Backstripping analysis of sedimentation in the Vilyui basin was used to assess the effect of both intraplate far-field forces and upwelling magma flows initiated by a mantle plume. A numerical thermomechanical model was developed to investigate the relations between two possible mechanisms by which the Vilyui rift was initiated: intraplate extension (passive rifting) and the ascent of a mantle magmatic diapir (active rifting). A model considering both of these mechanisms shows the contribution of the far-field extension forces and the effect of convective flows around the mantle plume, assuming

Timing, mantle source and origin of mafic dykes within the gravity anomaly belt of the Taihang-Da Hinggan gravity lineament, central North China Craton

NASA Astrophysics Data System (ADS)

Liu, Shen; Feng, Caixia; Feng, Guangying; Xu, Mengjing; Coulson, Ian M.; Guo, Xiaolei; Guo, Zhuang; Peng, Hao; Feng, Qiang

2017-09-01

Six mafic dyke swarms crop out in Hebei Province within the Taihang-Da Hinggan gravity lineament magmatic belt, China, and were sampled. Here, we present new zircon laser ablation-inductively coupled plasma-mass spectrometry U-Pb age, whole rock geochemical, and Sr-Nd-Pb-Hf isotopic data for the six areas where these mafic dykes occur. The mafic (dolerite) dykes formed between 131.6 ± 1.6 and 121.6 ± 1.1 Ma, and are enriched in the light rare earth elements (LREE), some of the large ion lithophile elements (LILE; e.g., Rb, Ba, and Sr) and Pb, and are depleted in Th, U, Nb and Ta; some samples are also depleted in Eu. The dykes have high initial 87Sr/86Sr ratios (0.7055-0.7057), negative εNd (t) values (-12.5 to -11.9), relatively constant Pb isotopic ratios ((206Pb/204Pb)i = 16.45-16.51, (207Pb/204Pb)i = 15.44-15.51, (208Pb/204Pb)i = 36.49-36.53), negative εHf (t) values (-18.2 to -15.1), and old Nd (TNdDM2; 2.17-2.47 Ga) and Hf (THfDM2; 2.28-2.33 Ga) model ages. These geochronological, geochemical, and isotopic data indicate that the dykes were derived from magmas generated by low to moderate degree partial melting (1.0%-10%) of an EM1-like garnet lherzolite mantle source; these magmas fractionated olivine, clinopyroxene, and hornblende prior to emplacement, and assimilated minimal amounts of crustal material. Several possible models have previously been proposed to explain the origin of Mesozoic magmatism in this region. However, here we propose a foundering model for these studied mafic dykes, involving the foundering of eclogite from thickened lower crust due to the collision between the Siberian Craton and the North China Craon.

Magma-maintained rift segmentation at continental rupture in the 2005 Afar dyking episode.

PubMed

Wright, Tim J; Ebinger, Cindy; Biggs, Juliet; Ayele, Atalay; Yirgu, Gezahegn; Keir, Derek; Stork, Anna

2006-07-20

Seafloor spreading centres show a regular along-axis segmentation thought to be produced by a segmented magma supply in the passively upwelling mantle. On the other hand, continental rifts are segmented by large offset normal faults, and many lack magmatism. It is unclear how, when and where the ubiquitous segmented melt zones are emplaced during the continental rupture process. Between 14 September and 4 October 2005, 163 earthquakes (magnitudes greater than 3.9) and a volcanic eruption occurred within the approximately 60-km-long Dabbahu magmatic segment of the Afar rift, a nascent seafloor spreading centre in stretched continental lithosphere. Here we present a three-dimensional deformation field for the Dabbahu rifting episode derived from satellite radar data, which shows that the entire segment ruptured, making it the largest to have occurred on land in the era of satellite geodesy. Simple elastic modelling shows that the magmatic segment opened by up to 8 m, yet seismic rupture can account for only 8 per cent of the observed deformation. Magma was injected along a dyke between depths of 2 and 9 km, corresponding to a total intrusion volume of approximately 2.5 km3. Much of the magma appears to have originated from shallow chambers beneath Dabbahu and Gabho volcanoes at the northern end of the segment, where an explosive fissural eruption occurred on 26 September 2005. Although comparable in magnitude to the ten year (1975-84) Krafla events in Iceland, seismic data suggest that most of the Dabbahu dyke intrusion occurred in less than a week. Thus, magma intrusion via dyking, rather than segmented normal faulting, maintains and probably initiated the along-axis segmentation along this sector of the Nubia-Arabia plate boundary.

Paleomagnetic study of 1765 Ma dyke swarm from the Singhbhum Craton: Implications to the paleogeography of India

NASA Astrophysics Data System (ADS)

Shankar, Ravi; Srinivasa Sarma, D.; Ramesh Babu, N.; Parashuramulu, V.

2018-05-01

We report the first key paleopole as a result of paleomagnetic study on a precisely dated 1765.3 ± 1.0 Ma WNW-ESE trending dyke swarm from Singhbhum Craton. This pole has been used in this study to propose the paleogeographic reconstruction of India with Baltica Craton and North China Craton. Incremental alternating field (AF) and thermal demagnetization, isolated high coercivity components with north to north-westerly declination and shallow negative inclination from 9 sampling sites which are representing different individual dykes. The primary origin of the ChRM is supported by the positive baked contact test. The WNW-ESE trending dykes yield a mean paleomagnetic direction with a declination = 329.2° and an inclination = -22.8° (k = 31.6; α95 = 9.3°). The positive bake contact test proves the primary nature of remanence. The pole position of Singhbhum Craton at 1765 Ma is 45°N, 311°E (dp = 5.2 and dm = 9.9). Paleogeographic reconstruction at ca. 1770 Ma, supported by geological, tectonic and metallogenic evidences indicate that the Baltica Craton and India linkage can be stable for at least ∼370 Ma (∼1770-1400 Ma). There is also reasonable evidence in support of India-North China Craton spatial proximity at ∼1770 Ma.

"Here nobody holds your heart": metaphoric and embodied emotions of birth and displacement among Karen women in Australia.

PubMed

Niner, Sara; Kokanovic, Renata; Cuthbert, Denise; Cho, Violet

2014-09-01

Our objective was to explore the ways in which displaced Karen mothers expressed emotions in narrative accounts of motherhood and displacement. We contextualized and analyzed interview data from an ethnographic study of birth and emotions among 15 displaced Karen mothers in Australia. We found that women shared a common symbolic language to describe emotions centered on the heart, which was also associated with heart "problems." This, along with hypertension, collapsing, or a feeling of surrender were associated responses to extremely adverse events experienced as displaced peoples. A metaphoric schema of emotional terms centered on the heart was connected to embodied expressions of emotion related to illness of the heart. This and other embodied responses were reactions to overwhelming difficulties and fear women endured due to their exposure to political conflict and global inequity. © 2014 by the American Anthropological Association.

Ethnomedicinal plants used for digestive system disorders by the Karen of northern Thailand.

PubMed

Tangjitman, Kornkanok; Wongsawad, Chalobol; Kamwong, Kaweesin; Sukkho, Treetip; Trisonthi, Chusie

2015-04-09

Digestive system disorders have a substantial effect on worldwide morbidity and mortality rates, including in Thailand, where the majority of the rural areas have a lack of proper sanitation and awareness about disease prevention. This has led to the prevalence of different types of digestive diseases. Karen people in Thailand still use medicinal plants as first aid remedies in treating these diseases. Therefore, this study aimed at documenting the plants used to cure and prevent different types of digestive system disorders by Karen people of Chiang Mai Province, northern Thailand. Ethnomedicinal data were collected from six key informants and 172 non-specialist informants regarding their traditional knowledge of medicinal plants. Quantitative approaches were used to determine Use Value (UV), Informant Consensus Factor (ICF) and Fidelity Level (FL) values. The study revealed that 36 medicinal plant species belonging to 31 genera and 24 families were used to treat digestive system disorders. The most prevalent plant families were Zingiberaceae (6 species), Euphorbiaceae (4 species) and Fabaceae (4 species). Leaves were the most commonly used plant part accounting for 32.6% of the plants, followed by the bark (18.6%). About 60% of the administrations were given orally by potion (60%) and consumption as food was also indicated (14%). The highest ICF values were recorded for carminative disorders, stomachaches, geographic tongue, constipation, appetite stimulants and food poisoning (1.00 each) indicating the best agreement among the informants knowledge of medicinal plants that were used to treat aliments in these categories. The highest fidelity level values were recorded for Punica granatum (100.00), Psidium guajava (95.45), and Gymnopetalum integrifolium (90.91) showing conformity of knowledge on species with the best healing potential. Medicinal plants still play an important role among Karen culture. The present information on these medicinal plants, which have

Palaeomagnetism of Precambrian dyke swarms in the North China Shield: The ˜1.8 Ga LIP event and crustal consolidation in late Palaeoproterozoic times

NASA Astrophysics Data System (ADS)

Piper, John D. A.; Jiasheng, Zhang; Huang, Baochung; Roberts, Andrew P.

2011-06-01

The North China Shield (NCS) is cut by a laterally-extensive dyke swarm emplaced at 1.78-1.76 Ga when an extensional regime succeeded regional metamorphism and completion of cratonisation by ˜1.85 Ga. Palaeomagnetic study of these dykes and adjoining metamorphic country rocks identifies a dominant shallow axis comprising a contiguous population with NE to N declinations and rare opposite polarity. Dykes with NE shallow magnetic declination (A1, D/ I = 36/-1°) recognised from previous study and emplaced in granulite terranes in the north are displaced by more northerly declinations (A2, D/ I = 8/2°) in lower grade metamorphic terranes to the south. Contact tests indicate a primary cooling-related origin to these magnetisations although tests are in part ambiguous because magnetisations in the granulite basement are comparable. Petrologic and rock magnetic considerations imply that magnetisation of the dykes occurred during uplift from depths as deep as 20 km following the peak of metamorphism at ˜1.85 Ga. A temporal migration A2 → A1 is implied by the higher crustal level and earlier acquisition of the former, and the deeper source and later acquisition of the latter. A third population of dyke magnetisations (A3, D/ I = 18/43°) is distributed towards steeper inclinations and close to the Mesozoic-Recent palaeofield. These are either partial or complete overprints of A1-A2 magnetisations with greater degrees of alteration indicated by demagnetisation and thermomagenetic spectra, or are much younger dykes of Mesozoic-Tertiary age. A minority fourth (later Precambrian but presently undated) dual polarity population has a magnetisation (11 dykes, D/ I = 108/7°) with contact tests indicating a primary cooling-related origin. The ˜1.78-1.76 Ga time of emplacement of the dominant dyke swarms in this study is widely represented by contemporaneous igneous rocks in other major shields linked to major Large Igneous Province (LIP)-related events. The new definition of

Family scapegoating in the life and works of Karen Blixen (Isak Dinesen).

PubMed

Hajal, F

1990-01-01

This article presents Karen Blixen's concept of the family scapegoat as it was elaborated in a number of her tales. This recurrent theme in her fictional writing is linked to events in her own family life, in particular her own assumption of a scapegoat-prodigal child role during the "African period" of her life. Furthermore, her assumption of this role and her particular view of her destiny, pitting her against the rest of her family, was related to her strong identification with her father, intensified following his suicide when she was a child.

Upper Triassic mafic dykes of Lake Nyos, Cameroon (West Africa) I: K-Ar age evidence within the context of Cameroon Line magmatism, and the tectonic significance

NASA Astrophysics Data System (ADS)

Aka, Festus Tongwa; Hasegawa, Takeshi; Nche, Linus Anye; Asaah, Asobo Nkengmatia Elvis; Mimba, Mumbfu Ernestine; Teitchou, Isidore; Ngwa, Caroline; Miyabuchi, Yasuo; Kobayashi, Tetsuo; Kankeu, Boniface; Yokoyama, Tetsuya; Tanyileke, Gregory; Ohba, Takeshi; Hell, Joseph Victor; Kusakabe, Minoru

2018-05-01

The hydrodynamic fragmentation that formed Lake Nyos in northwest Cameroon did not only make it the most unpopular lake in the world from a gas disaster perspective, it also opened a rare and formidable window through which much of the geology of Cameroon can be studied in a single locality. The Cambrian quartz monzonite cliff excavated by the maar-forming explosion and exposed in its northeastern shore is intruded by mafic dykes, two of which we dated. Even though close to one another, the dykes are different in composition. The alkaline dyke yields a slightly older (Carnian) K-Ar fedspar age of 231.1 ± 4.8 Ma, while the sub alkaline dyke yields an age of 224.8 ± 4.7 Ma (Norian). Based on radioisotopic age data available over the last 48 years (347 data) for the Cameroon Line magmatism comprising eruptives and volcano-plutonic complexes, the Nyos dykes are way older than the Cameroon Line, and even pre-date the Lower Cretaceous initiation of west Gondwana fragmentation in Equatorial Atlantic domain. They would therefore not have been directly linked to the formation of the Cameroon Line. Alternatively, they might be associated with the development of intra-continental rift systems in West Central Africa that pre-dated west Gondwana breakup to form the Atlantic Ocean.

Integration of geotechnical and geophysical techniques for the characterization of a small earth-filled canal dyke and the localization of water leakage

NASA Astrophysics Data System (ADS)

Bièvre, Grégory; Lacroix, Pascal; Oxarango, Laurent; Goutaland, David; Monnot, Guy; Fargier, Yannick

2017-04-01

This paper investigates the combined use of extensive geotechnical, hydrogeological and geophysical techniques to assess a small earth dyke with a permanent hydraulic head, namely a canal embankment. The experimental site was chosen because of known issues regarding internal erosion and piping phenomena. Two leakages were visually located following the emptying of the canal prior to remediation works. The results showed a good agreement between the geophysical imaging techniques (Electrical Resistivity Tomography, P- and SH-waves Tomography) and the geotechnical data to detect the depth to the bedrock and its lateral variations. It appeared that surface waves might not be fully adapted for dyke investigation because of the particular geometry of the studied dyke, non-respectful of the 1D assumption, and which induced depth and velocity discrepancies retrieved from Rayleigh and Love waves inversion. The use of these classical prospecting techniques however did not allow to directly locate the two leakages within the studied earth dyke. The analysis of ambient vibration time series with a modified beam-forming algorithm allowed to localize the most energetic water flow prior to remediation works. It was not possible to detect the leakage after remediation works, suggesting that they efficiently contributed to significantly reduce the water flow. The second leakage was not detected probably because of a non-turbulent water flow, generating few energetic vibrations.

Satellite-based observations of unexpected coastal changes due to the Saemangeum Dyke construction, Korea.

PubMed

Lee, Yoon-Kyung; Ryu, Joo-Hyung; Choi, Jong-Kuk; Lee, Seok; Woo, Han-Jun

2015-08-15

Spatial and temporal changes around an area of conventional coastal engineering can be easily observed from field surveys because of the clear cause-and-effect observable in the before and after stages of the project. However, it is more difficult to determine environmental changes in the vicinity of tidal flats and coastal areas that are a considerable distance from the project. To identify any unexpected environmental impacts of the construction of Saemangeum Dyke in the area, we examined morphological changes identified by satellite-based observations through a field survey on Gomso Bay tidal flats (15km from Saemangeum Dyke), and changes in the suspended sediment distribution identified by satellite-based observations through a hydrodynamic analysis in the Saemangeum and Gomso coastal area. We argue that hydrodynamic changes due to conventional coastal engineering can affect the sedimentation pattern in the vicinity of tidal flats. We suggest that the environmental impact assessment conducted before a conventional coastal engineering project should include a larger area than is currently considered. Copyright © 2015 Elsevier Ltd. All rights reserved.

REE investigation of the Motru Dyke System components from the Danubian basements (South Carpathians, Romania)

NASA Astrophysics Data System (ADS)

Campeanu, Mara; Balica, Constantin; Balintoni, Ioan; Tănăselia, Claudiu; Cadar, Oana

2017-04-01

Dragsan and Lainici-Paius groups represent the basement components of the Danubian Alpine units (South Carpathians, Romania), which consist of medium-grade metamorphic rocks. A subvolcanic system of dykes (i.e. Motru Dyke System - MDS) crosscut mostly the Lainici Paius basement as an effect of a late-Variscan termo-tectonic event. The geochemical features, frame the MDS components within a wide range of petrotypes (basaltic andesites to rhyolites), and define a wide differentiation series. Classically this subvolcanic system was inferred to be in connection to a unique mantle source [1], however, recent studies [2,3] suggest a mixed mantle-crust source, based on the interpretation of the trace elements in conjunction with Sr and Nd isotope data. Aditionally, the presence of relict zircon grains consolidates this assumption. New REE data collected from eight MDS components, generally confirm the mixed mantle-crust source hypothesis. The distribution patterns reveal two groups of samples. The first group (six samples) is moderately enriched in REE and shows moderately fractionated patterns with (La/Yb)N between 7-21 and low Eu/Eu* (0.81-0.9). The second group, strongly enriched in light REE, have high (La/Yb)N and strong negative Eu anomaly (Eu/Eu* of 0.41 and 0.38 respectively). REE vary between 107-147 ppm for the first group and 612 ppm - 907ppm for the second group. We can assume a stronger fractionation of plagioclase as well as of garnet and amphibole for the second group. With a flatter pattern, for the first group of samples, the fractionation of these minerals appears to be moderate. The emplacement age of MDS has been long disputed, since it was supposed as pre-Silurian for a long time. However, newly zircon U/Pb isotopic dating performed on two collected samples indicate a mean age of 300 My [2,3]. Owing to the croscutting relationships with the post-colisional granitoid plutons emplaced in the Danubian basement during the late Variscan, and based on

Clinopyroxenite dykes within a banded unit in the basal mantle section of the northern part of the Oman ophiolite: A record of the latest deep-seated magmatism

NASA Astrophysics Data System (ADS)

Ishimaru, Satoko; Arai, Shoji; Tamura, Akihiro

2017-11-01

We found clinopyroxenite dykes in a banded harzburgite block within the Sumeini area in the uppermost part of the metamorphic sole of the northern part of the Oman ophiolite. The dykes clearly cut the deformational structure of the harzburgite and contain its fragments, indicating dyke formation during obduction of the ophiolite. The Mg# [= Mg / (Mg + total Fe)] of clinopyroxenes in the dykes ranges from 0.81 to 0.91, and increases up to 0.93 proximal to harzburgite fragments. Mantle minerals in the harzburgite fragments were modified chemically through interaction with the magma that formed the dyke, yielding lower clinopyroxene and spinel Mg#, and spinels with higher TiO2 contents than those in the unaltered harzburgite. These geochemical features indicate that the clinopyroxenite dykes are cumulates derived from a relatively deep-seated primitive magma enriched in light rare earth elements (LREE) with an ocean island basalt (OIB)-like affinity, geochemically similar to the V3 lavas of an off-ridge origin. Combining these data with geological observations suggests that the clinopyroxenite dykes represent root system of the V3 lavas. Our analyses of the clinopyroxenite dykes testify to the external nature of the V3 magmas, which was added to the sliced oceanic lithosphere from the outside. It is likely that the V3 magma underwent deep-seated crystallization of clinopyroxene and had limited interaction with mantle peridotite en route to the surface. The mode of occurrence of the Sumeini clinopyroxenites (i.e., emplaced into a banded harzburgite block surrounded by garnet amphibolite) is consistent with the generation of OIB-like magmas (V3 lava) beneath the Oman ophiolite resulting from the break-off of the "subducting slab" and subsequent infiltration of hot asthenospheric mantle. This view is consistent with the limited distribution of V3-related rocks in the Oman ophiolite. The production of such OIB-like magmas during ophiolite obduction is not a rare event

Paleomagnetism of Devonian dykes in the northern Kola Peninsula and its bearing on the apparent polar wander path of Baltica in the Precambrian

NASA Astrophysics Data System (ADS)

Veselovskiy, Roman V.; Bazhenov, Mikhail L.; Arzamastsev, Andrey A.

2016-04-01

Mafic dykes and large alkaline and carbonatite intrusions of Middle-Late Devonian age are widespread on the Kola Peninsula in NE Fennoscandia. These magmatic rocks are well characterized with petrographic, geochemical and geochronological data but no paleomagnetic results have been reported yet. We studied dolerite dykes from the northern part of the Peninsula and isolated three paleomagnetic components in these rocks. A low-temperature component is aligned along the present-day field, while a major constituent of natural remanent magnetization is an intermediate-temperature component (Decl. = 79.6°, Inc. = 78.5°, α95 = 5,9°, N = 17 sites) that is present in most Devonian dykes but is found in some baked metamorphic rocks and Proterozoic dykes too. Finally, a primary Devonian component could be reliably isolated from two dykes only. Rock-magnetic studies point to presumably primary low-Ti titanomagnetite and/or pure magnetite as the main remanence carriers but also reveal alteration of the primary minerals and the formation of new magnetic phases. The directions of a major component differ from the Middle Paleozoic reference data for Baltica but closely match those for the 190 ± 10 Ma interval recalculated from the apparent polar wander path of the craton. We assume that this Early Jurassic component is a low-temperature overprint of chemical origin. The main impact of the new results is not to mid-Paleozoic or Early Mesozoic times but to much older epochs. Analysis of paleomagnetic data shows that the directionally similar remanences are present in objects with the ages ranging from 500 Ma to 2 Ga over entire Fennoscandia. Hence we argue that an Early Jurassic remagnetization is of regional extent but cannot link it to a certain process and a certain tectonic event. If true, this hypothesis necessitates a major revision of the APWP for Baltica over a wide time interval.

New constraints on the geochronology and Sm-Nd isotopic characteristics of Bas-Drâa mafic dykes, Anti-Atlas of Morocco

NASA Astrophysics Data System (ADS)

El Bahat, Abdelhakim; Ikenne, Moha; Cousens, Brian; Söderlund, Ulf; Ernst, Richard; Klausen, Martin B.; Youbi, Nasrrddine

2017-03-01

The Precambrian inliers of the Anti-Atlas belt across the southern part of Morocco contain numerous mafic dyke and sill swarms, which are thought to represent the erosional remnants of Proterozoic Large Igneous Provinces (LIPs). As part of an extended research campaign to date and characterize these LIPs, two amphiboles from one dyke within the Bas-Drâa inlier (western Anti-Atlas) yielded consistent 40Ar-39Ar ages of 611 Ma ± 1.3; i.e., evidence of magmatic activity during the Ediacaran (635-542 Ma). Furthermore, Nd isotope ratios and model ages identifies four groups of dykes within the Bas-Drâa inlier, all of which were derived from a previously enriched mantle reservoir with very low 143Nd/144Nd ratios (0.51065-0.51170) and corresponding εNd(t) values (-16.44 to -2.45). Such low Nd-ratios arguably reflect either a contribution of crustal components, such as the Paleoproterozoïc schisto-granitic basement, or metasomatic modification of the sub-continental lithospheric mantle.

Proterozoic Diabase Dyke Swarms of Northern Ontario: Paleomagnetic Indicators of Broad-Scale Crustal Deformation of the Archean Superior Province

NASA Astrophysics Data System (ADS)

Halls, H. C.

2004-05-01

Several Proterozoic dyke swarms, all with precise U-Pb ages, (Matachewan, Senneterre, Biscotasing, Marathon and Fort Frances) occur over an area of the southern Superior Province covering more than 300,000 square kilometres. Cutting across this region is the Kapuskasing Zone, a 500 km-long fault zone along which dextral transpression at about 1.9 to 2.0 Ga has produced crustal uplift locally in excess of 20 km and lateral fault displacements of up to 70 km (Percival and West, 1994). The 2446-2473 Ma Matachewan swarm has been a subject for study throughout the last 40 years of Canadian paleomagnetism. However only in the last 20 years has the true size of the swarm been realised (Ernst and Halls, 1984; Halls et al., 1994), and the discovery made that regional variations in the direction of primary magnetization in the dykes are intimately related to the Kapuskasing Zone (KZ). The swarm is now known to span a single reversal of the Earth's magnetic field. The younger N polarity epoch, although barely recorded in the dying stages of the intrusive episode, is well preserved in dykes within uplifted crust inside the KZ. Here fine-grained magnetite, exsolved from dyke feldspars due to slow cooling of the swarm at depth, acquired a remanence of probable thermo-chemical origin prior to or during crustal uplift (Halls and Palmer, 1990; Halls et al., 1994; Halls and Zhang, 2003). The inference is that dykes intruded during the older R polarity epoch carry a near surface primary R magnetization but have been remagnetized to N at depth. Paleomagnetic data from that part of the swarm outside the KZ are therefore dominated by the older R polarity magnetization. They show that the western half of the shield has rotated counter-clockwise about 10 to 20 degrees relative to the eastern half across the KZ (Bates and Halls, 1991; Halls and Stott, 2003). This rotation is also seen in paleomagnetic data from the 2170 Ma Biscotasing swarm, which is now known to occur on both sides of the

Palaeointensity determinations on rocks from the Achaean- Paleoproterozoic dykes from the Karelian craton

NASA Astrophysics Data System (ADS)

Shcherbakov, Valera; Shcherbakova, Valentina; Lubnina, Natalia; Zhidkov, Grigory; Tsel'movich, Vladimir

2017-04-01

The Karelian craton was a fragment of either an earlier late Archean supercontinent, sometimes referred to as Kenorland. Now the craton is a large Archean composite granite-greenstone terrane in the eastern part of the Fennoscandian Shield bounded by Paleoproterozoic Svecofennian orogen in the south-west and by Lapland-Kola orogen in the north-east and Belomorian province in the east-north-east. Mafic dykes, volcanic rocks, sills, and layered intrusions with ages of ca. 2.51-2.45 Ga and ca. 2.06-1.95 Ga are widespread and well-studied in the Karelian Craton. Paleointensity (Banc) results obtained on the Shala dike (age of 2504 Ma by U-Pb, ID TIMS) tracked near vl. Shala and on the Deda island are discussed here. Eighteen block samples of gabbronotires were collected in two sites in the Shala quarry. Stepwise thermal demagnetization (≤ 20 steps, up to 600 C) and stepwise AF demagnetization were done. To monitor possible mineralogical changes during thermal cleaning, magnetic susceptibility was measured after each heating step. Intensive rock magnetic investigations and thermal palaeointensity experiments using the Thellier-Coe (with check-points) and Wilson procedures were carried out. Electronic microscopy study of two samples was made too. For the exception of a viscous component some specimens from the contact zone of the gabbronorite dyke with thin dolerite dyke show two distinct components. The first E-NE intermediate-down direction component was separated at fields up to 50-60 mT and unblocking temperatures up to 520-540 C. The other S-SE low-down direction component is separated at fields from 60 to 100 mT and unblocking temperatures from 540 to 590-600 C. Based on the positive contact tests for the gabbronorite dyke, the S-SE shallow inclination remanence (I = -5.7 degrees) is interpreted to be of primary origin. Reliable palaeointensity determinations Banc fitting a set of selection criteria were determined on 13 samples from 2 sites carrying

Public knowledge of diabetes in Karen Ethnic rural residents: a community-based questionnaires study in the far north-west of Thailand

PubMed Central

Lorga, Thaworn; Srithong, Kannapatch; Manokulanan, Pratumpan; Aung, Thin Nyein Nyein; Aung, Myo Nyein

2012-01-01

Background and purpose The public knowledge of diabetes is important for prevention of disease. This study aimed to evaluate knowledge of diabetes, risk factors, and the common warning signs of diabetes and complications among community participants in a rural Karen ethnic community. Methods Participants were asked to answer a questionnaire regarding their knowledge of diabetes. Fasting blood glucose testing, blood pressure measurement, and body mass index (BMI) assessment were provided to the participants. The study was conducted at Thasongyang district, Tak province, Thailand. Results A total of 299 Karen rural residents were included in the study. The median age was 45 years and median fasting blood glucose was 88 mg/dL. The response rate to the questionnaires was 91.97%. Half of the participants knew diabetes is a noncommunicable disease needing lifelong treatment. Overall, one-third of the community participants could correctly answer the knowledge assessment questions regarding risk factors and common features of diabetes. whereas the other two-thirds either gave a wrong answer or were “not sure”. Female participants had poorer diabetes knowledge than the males. Conclusion The public knowledge of diabetes, as represented by this sample of the Karen ethic community, is alarmingly low. There is significant gender difference in knowledge level. Culturally tailored and gender-sensitive diabetes health education interventions are urgently needed in this minority ethnic community. PMID:23055769

Principles & Practices Board remains a valuable resource to members. Interview by Karen Hackett.

PubMed

McCue, J P

1986-01-01

In this interview, Joseph P. McCue, FHFMA, CPA, chairman of HFMA's Principles & Practices Board, discusses the history and activity of the Board since its start in 1975. According to McCue, the Board was originally formed to address the technical accounting and reporting questions unique to the healthcare industry, and nothing has changed HFMA's opinion that such a mission is still important--the necessity for a P&P Board is as acute now as it was in 1975. The interviewer is Karen Hackett, CMPA, an HFMA staff liaison with the Board.

The Chara-Sina dyke swarm in the structure of the Middle Paleozoic Vilyui rift system (Siberian Craton)

NASA Astrophysics Data System (ADS)

Kiselev, A. I.; Konstantinov, K. M.; Yarmolyuk, V. V.; Ivanov, A. V.

2016-11-01

The formation of the Vilyui rift system in the eastern Siberian Craton was finished with breakdown of the continent and formation of its eastern margin. A characteristic feature of this rift system is the radial distribution of dyke swarms of basic rocks. This peculiarity allows us to relate it to the breaking processes above the mantle plume, the center of which was located in the region overlain in the modern structure by the foreland of the Verkhoyan folded-thrust belt. The Chara-Sina dyke swarm is the southern part of a large area of Middle Paleozoic basaltic magmatism in the eastern Siberian Craton. The OIB-like geochemical characteristics of dolerite allow us to suggest that the melting substrate for Middle Paleozoic basaltic magmatism was represented by a relatively homogeneous, mid-depleted mantle of the plume with geochemical parameters similar to those of OIB.

Karen and Lawa medicinal plant use: uniformity or ethnic divergence?

PubMed

Junsongduang, Auemporn; Balslev, Henrik; Inta, Angkhana; Jampeetong, Arunothai; Wangpakapattanawong, Prasit

2014-01-01

We here tease apart the ethnopharmacological knowledge of plants in two Thai villages to determine to which degree the uses are particular to individual ethnic groups and to which degree they are part of a generalized and uniform set of widespread medicinal plants used over a large geographic range. We compared Karen and Lawa knowledge of medicinal plants in the Mae Cheam watershed of northern Thailand, where both ethnic groups have settled and share ecological conditions for resource extraction. We were interested in documenting the degree to which these two ethnic groups use the same or different medicinal plant species. The use of the same plant species by the two groups was considered a sign of uniform and cross-cultural local knowledge, whereas the use of different medicinal plants by each group was considered a sign of culturally specific local knowledge that developed within each ethnic group. We inventoried the plant species in different habitats around one Karen village and one Lawa village using stratified vegetation plots and using semi-structured questionnaires we interviewed 67 key informants regarding their use of plants for medicine. We then calculated the Fidelity level FL (FL values near 100% for a species indicate that almost all use reports refer to the same way of using the species, whereas low FL values indicate that a species is used for many different purposes) and cultural importance index CI (the sum of the proportion of informants that mention each of the use categories for a given species) to estimate the variation in medicinal plant use. We used Jaccard's Index JI (This index relates the number of shared species to the total number of species) to analyze the similarity of medicinal plant use between the two villages. A total of 103 species of medicinal plant species in 87 genera and 41 families were identified and they were used to cure 35 ailments. The FL of the medicinal plant species varied from 10% to 100%, was different for each

Populations of Rice Grain Bug, Paraeuscosmetus pallicomis, (Hemiptera: Lygaeidae) in Weed-free Paddy Field, Weedy Paddy Field and Paddy Dykes.

PubMed

Abdullah, Tamrin; Nasruddin, Andi; Agus, Nurariaty

2017-07-01

Research on the populations of rice grain bug Paraeuscosmetus pallicomis Dallas (Hemiptera: Lygaeidae) in paddy field ecosystems was performed with the aim to determine the populations of rice grain bug in weed-free paddy field, weedy paddy field, and paddy dykes. Experiment was carried out in the village of Paccellekang in the district of Patallasang of Gowa Regency in South Sulawesi, Indonesia. Observations were performed during the milky grain stage (85 days after planting), the mature grain stage (105 days after planting), and one day after harvest (115 days after transplanting). Results showed that 85 days after the transplanting, the populations of rice grain bug was significantly higher in the weedy paddy field compared to weed-free field and paddy dykes with total numbers of 1.75, 3.53, and 0.31 insects per 2 hills, respectively. Similarly, 105 days after the transplanting, 2.53, 5.53, and 0.11 insects per hill, respectively. However, one day after the harvest (115 days after transplanting) the number of insects in weed-free field decreased, while in the dykes increased, and the weedy plot still had the highest number of insects per 2 hills. Our results suggested that weeds played an important role in regulating the bug population by providing alternative shelter and foods for the insect.

Weaving Colors into a White Landscape: Unpacking the Silences in Karen Hesse's Children's Novel "Out of the Dust"

ERIC Educational Resources Information Center

Simon, Lisa

2008-01-01

The children's novel "Out of the Dust" (Hesse, 1997) is an evocative portrayal of the drought and dust storms that devastated Midwestern farms in the 1930s. Through the voice of her 13-year-old narrator, Karen Hesse intertwines history and free verse poetry to create what many readers find to be a moving depiction of the Oklahoma…

Contribution of the FUTUREVOLC project to the study of segmented lateral dyke growth in the 2014 rifting event at Bárðarbunga volcanic system, Iceland

NASA Astrophysics Data System (ADS)

Sigmundsson, Freysteinn; Hooper, Andrew; Hreinsdóttir, Sigrún; Vogfjörd, Kristín S.; Ófeigsson, Benedikt; Rafn Heimisson, Elías; Dumont, Stéphanie; Parks, Michelle; Spaans, Karsten; Guðmundsson, Gunnar B.; Drouin, Vincent; Árnadóttir, Thóra; Jónsdóttir, Kristín; Gudmundsson, Magnús T.; Samsonov, Sergey; Brandsdóttir, Bryndís; White, Robert S.; Ágústsdóttir, Thorbjörg; Björnsson, Helgi; Bean, Christopher J.

2015-04-01

The FUTUREVOLC project (a 26-partner project funded by FP7 Environment Programme of the European Commission, addressing topic "Long-term monitoring experiment in geologically active regions of Europe prone to natural hazards: the Supersite concept) set aims to (i) establish an innovative volcano monitoring system and strategy, (ii) develop new methods for near real-time integration of multi-parametric datasets, (iii) apply a seamless transdisciplinary approach to further scientific understanding of magmatic processes, and (iv) to improve delivery, quality and timeliness of transdisciplinary information from monitoring scientists to civil protection. The project duration is 1 October 2012 - 31 March 2016. Unrest and volcanic activity since August 2014 at one of the focus areas of the project in Iceland, at the Bárðarbunga volcanic system, near the middle of the project duration, has offered unique opportunities for this project. On 16 August 2014 an intense seismic swarm started in Bárðarbunga, the beginning of a major volcano-tectonic rifting event forming over 45 km long dyke extending from the caldera to Holuhraun lava field outside the northern margin of Vatnajökull. A large basaltic, effusive fissure eruption began in Holuhraun on 31 August which had by January formed a lava field with a volume in excess of one cubic kilometre. We document how the FUTUREVOLC project has contributed to the study and response to the subsurface dyke formation, through increased seismic and geodetic coverage and joint interpreation of the data. The dyke intrusion in the Bárðarbunga volcanic system, grew laterally for over 45 km at a variable rate, with an influence of topography on the direction of propagation. Barriers at the ends of each segment were overcome by the build-up of pressure in the dyke end; then a new segment formed and dyke lengthening temporarily peaked. The dyke evolution, which occurred over 14 days, was revealed by propagating seismicity, ground

Vitamin A status of the minority ethnic group of Karen hill tribe children aged 1-6 years in Northern Thailand.

PubMed

Tienboon, Prasong; Wangpakapattanawong, Prasit

2007-01-01

Vitamin A deficiency (VAD) is the most common cause of childhood blindness in the developing world. It is estimated that by giving adequate vitamin A, in vitamin A deficient populations, child mortality from measles can be reduced by 50%, and mortality from diarrheal disease by 40%. Overall mortality in children 6-59 months of age can be reduced by 23%. This paper reported results from a study of vitamin A status and malnutrition of the minority ethnic group of Karen hill tribe children aged 1-6 years in the north of Thailand. All children aged 1-6 years (N = 158; 83 boys, 75 girls) from the three Karen villages (Mae Hae Tai, Mae Yot, Mae Raek) of Mae Chaem district in the north of Thailand were studied. The Karen is the largest mountain ethnic minority ("hill tribe") group in Thailand. All children were examined by a qualified medical doctor and were assessed for their vitamin A intakes using 24 hours dietary recall. Thai food composition table from Ministry of Health, Thailand were used as references. The results were compared with the Thai Recommended Dietary Allowances. Children aged 1-3 years and 4-6 years were separately analysed due to the differences in Thai Recommended Dietary Allowances between the two age groups. A whole blood of 300 microL was obtained by "fingerstick" for determination of serum vitamin A. Community or village's vitamin A status was assessed by using Simplified Dietary Assessment (SDA) method and Helen Keller International (HKI) food frequency method. Descriptive statistics were used to analyse the data. All families of the study boys and girls had income lower than the Thailand poverty line (US $ 1,000/year). On average, 63% of children from Mae Hae Tai village, 1.5% of children from Mae Yot village and none of children from Mae Raek village had serum vitamin A<0.7 micromol/L which indicated VAD. All boys and only girls from Mae Raek village consumed vitamin A more than the Thai RDA but girls from Mae Hae Tai village and Mae Yot

Populations of Rice Grain Bug, Paraeuscosmetus pallicomis, (Hemiptera: Lygaeidae) in Weed-free Paddy Field, Weedy Paddy Field and Paddy Dykes

PubMed Central

Abdullah, Tamrin; Nasruddin, Andi; Agus, Nurariaty

2017-01-01

Research on the populations of rice grain bug Paraeuscosmetus pallicomis Dallas (Hemiptera: Lygaeidae) in paddy field ecosystems was performed with the aim to determine the populations of rice grain bug in weed-free paddy field, weedy paddy field, and paddy dykes. Experiment was carried out in the village of Paccellekang in the district of Patallasang of Gowa Regency in South Sulawesi, Indonesia. Observations were performed during the milky grain stage (85 days after planting), the mature grain stage (105 days after planting), and one day after harvest (115 days after transplanting). Results showed that 85 days after the transplanting, the populations of rice grain bug was significantly higher in the weedy paddy field compared to weed-free field and paddy dykes with total numbers of 1.75, 3.53, and 0.31 insects per 2 hills, respectively. Similarly, 105 days after the transplanting, 2.53, 5.53, and 0.11 insects per hill, respectively. However, one day after the harvest (115 days after transplanting) the number of insects in weed-free field decreased, while in the dykes increased, and the weedy plot still had the highest number of insects per 2 hills. Our results suggested that weeds played an important role in regulating the bug population by providing alternative shelter and foods for the insect. PMID:28890757

Valles Marineris as a Cryokarstic Structure Formed by a Giant Dyke System: Support From New Analogue Experiments

NASA Astrophysics Data System (ADS)

Ozeren, M. S.; Sengor, A. M. C.; Acar, D.; Ülgen, S. C.; Onsel, I. E.

2014-12-01

Valles Marineris is the most significant near-linear depression on Mars. It is some 4000 km long, up to about 200 km wide and some 7 km deep. Although its margins look parallel at first sight, the entire structure has a long spindle shape with significant enlargement in its middle (Melas Chasma) caused by cuspate slope retreat mechanisms. Farther to its north is Hebes Chasma which is an entirely closed depression with a more pronounced spindle shape. Tithonium Chasma is a parallel, but much narrower depression to its northeast. All these chasmae have axes parallel with one another and such structures occur nowhere else on Mars. A scabland surface exists to the east of the Valles Marineris and the causative water mass seems to have issued from it. The great resemblance of these chasmae on mars to poljes in the karstic regions on earth have led us to assume that they owed their existence to dissolution of rock layers underlying them. We assumed that the dissolving layer consisted of water ice forming substantial layers, in fact entirely frozen seas of several km depth. We have simulated this geometry by using bentonite and flour layers (in different experiments) overlying layers of ice in which a resistant coil was used to simulate a dyke. We used different thicknesses of bentonite and flour overlying ice layers again of various thicknesses. The flour seems to simulate the Martian crust better because on Mars, g is only about 3/8ths of its value on Earth, so (for equal crustal density) the depth to which the cohesion term C remains important in the Mohr-Coulomb shear failure criterion is about 8/3 times greater. As examples we show two of those experiments in which both the rock analogue and ice layers were of 1.5 cm. thick. Perfect analogues of the Valles Marineris formed above the dyke analogue thermal source complete with the near-linear structure, overall flat spindle shape, cuspate margins, a central ridge, parallel side faults, parallel depressions resembling

Mapping and characterization from aeromagnetic data of the Foum Zguid dolerite Dyke (Anti-Atlas, Morocco) a member of the Central Atlantic Magmatic Province (CAMP)

NASA Astrophysics Data System (ADS)

Bouiflane, Mustapha; Manar, Ahmed; Medina, Fida; Youbi, Nasrrddine; Rimi, Abdelkrim

2017-06-01

A high-resolution aeromagnetic survey was carried out in the Anti- Atlas, Morocco covering the main areas traversed by the Great CAMP Foum Zguid dyke (FZD). This ;doleritic; dyke belongs to the Central Atlantic Magmatic Province (CAMP), a Large Igneous Province which is associated with the fragmentation of the supercontinent Pangaea and the initial stages of rifting of the Central Atlantic Ocean. It also coincides in time with the mass extinction of the Triassic - Jurassic boundary. Based on the study of geological maps and Google Earth satellite images, it appears that the FZD is poorly exposed and, often covered by Quaternary deposits. This work proposes aeromagnetic modelling and interpretation of the FZD in order to better constrain its structural extent. The data have allowed (i) mapping of the dyke over great distances, under the Quaternary deposits and through areas where it was poorly characterized on the geological map; (ii) identifying major tectonic lineaments interpreted as faults; (iii) recognizing magnetic anomalies related to mafic intrusive bodies; and (iv) informing about regional structural context.

Integrated elemental and Sr-Nd-Pb-Hf isotopic studies of Mesozoic mafic dykes from the eastern North China Craton: implications for the dramatic transformation of lithospheric mantle

NASA Astrophysics Data System (ADS)

Liu, Shen; Feng, Caixia; Santosh, M.; Feng, Guangying; Coulson, Ian M.; Xu, Mengjing; Guo, Zhuang; Guo, Xiaolei; Peng, Hao; Feng, Qiang

2018-02-01

Evolution of the lithospheric mantle beneath the North China Craton (NCC) from its Precambrian cratonic architecture until Paleozoic, and the transformation to an oceanic realm during Mesozoic, with implications on the destruction of cratonic root have attracted global attention. Here we present geochemical and isotopic data on a suite of newly identified Mesozoic mafic dyke swarms from the Longwangmiao, Weijiazhuang, Mengjiazhuang, Jiayou, Huangmi, and Xiahonghe areas (Qianhuai Block) along the eastern NCC with an attempt to gain further insights on the lithospheric evolution of the region. The Longwangmiao dykes are alkaline with LILE (Ba and K)- and LREE-enrichment ((La/Yb) N > 4.3) and EM1-like Sr-Nd-Pb-Hf isotopic signature ((87Sr/86Sr) i > 0.706; ε Nd (t) < -6.3, (206Pb/204Pb) i > 16.6, (207Pb/204Pb) i > 15.4, (208Pb/204Pb) i > 36.8, ε Hf (t) < -22.4). The Weijiazhuang dykes are sub-alkaline with LILE (Ba and K)- and LREE-enrichment ((La/Yb) N > 3.7), and display similar EM1-like isotopic features ((87Sr/86Sr) i > 0.706; ε Nd (t) < -7.0, (206Pb/204Pb) i > 16.7, (207Pb/204Pb) i > 15.4, (208Pb/204Pb) i > 36.9, ε Hf (t) < -23.3). The Mengjiazhuang dykes are also sub-alkaline with LILE (Ba and K)- and LREE-enrichment ((La/Yb) N > 2.4) and EM1-like isotopic features((87Sr/86Sr) i > 0.706; ε Nd (t) < -18.4, (206Pb/204Pb) i > 16.7, (207Pb/204Pb) i > 15.4, (208Pb/204Pb) i > 36.9, ε Hf (t) < -8.6). The Jiayou dykes also display sub-alkaline affinity with LILE (Ba and K)- and LREE-enrichment ((La/Yb) N > 3.7) and EM1-like Sr-Nd-Pb-Hf isotopic features ((87Sr/86Sr) i > 0.706; ε Nd(t) < -15.3, (206Pb/204Pb) i > 16.7, (207Pb/204Pb) i > 15.4, (208Pb/204Pb) i > 36.9, ε Hf (t) < -18.4). The Huangmi dykes are alkaline (with Na2O + K2O ranging to more than 5.9 wt.%)) with LILE (Ba and K)- and LREE-enrichment ((La/Yb) N > 9.3) and EM1-like isotopic composition ((87Sr/86Sr) i > 0.705; ε Nd (t) < -15.1, (206Pb/204Pb) i > 16.9, (207Pb/204Pb) i > 15.5, (208Pb/204Pb) i > 36

Current prevalence of intestinal parasitic infections and their impact on hematological and nutritional status among Karen hill tribe children in Omkoi District, Chiang Mai Province, Thailand.

PubMed

Yanola, Jintana; Nachaiwieng, Woottichai; Duangmano, Suwit; Prasannarong, Mujalin; Somboon, Pradya; Pornprasert, Sakorn

2018-04-01

Intestinal parasitic infection represents a substantial problem for children living in rural or limited resources areas and significantly relates to anemia and nutritional status. This study aimed to determine the current prevalence of intestinal parasitic infections among school-age children of Karen hill tribe population in Omkoi District, Chiang Mai Province, Thailand and assess the impact of intestinal parasitic infection on hematological and nutritional status in those children. A total of 375 Karen hill tribe children, 6-14 years of age, in Omkoi District were randomly selected to participate in this study. Stool samples were collected and examined for intestinal parasitic infection through formalin-ether concentration method. Blood samples were collected for hematological and iron analysis. The overall prevalence of intestinal parasitic infection was 47.7% (179/375), with single infections (29.3%) and polyparatism (18.4%). The most common pathogenic parasite was Trichuris trichiura (16.0%), followed by Ascaris lumbricoides (13%) and Giardia lamblia (3.5%). In addition, non-pathogenic amoeba, Entamoeba coli was observed with a high prevalence rate (31.2%). Anemia and eosinophilia prevalence were 6.40% (24/375) and 74.7% (280/375), respectively. Eosinophilia was significantly more prevalent in children with intestinal parasitic infection compared to uninfected children. Among 249 children, 13.7% were iron deficiency, 9.6% were thalassemia and hemoglobinophathy and 8% were G-6-PD deficiency. A high prevalence infection rate was significantly associated with eosinophilia, but independently related to anemia and iron deficiency. Intestinal parasitic infections are endemic in school-age children of Karen hill tribe population in Omkoi District. These data highlight the need for an integrated approach to control transmission of intestinal parasites and improve the health and sanitation status of Karen hill tribe children in Thailand. Copyright © 2018 Elsevier B

Complicated and messy politics of inclusion: Michfest and the Boston Dyke March.

PubMed

Trigilio, Jo

2016-01-01

To illustrate the challenge of political organizing that grapples with identity politics and inclusion, I focus on two women-centered annual events with very different politics of inclusion: the Michigan Womyn's Music Festival and the Boston Dyke March. (1) arguments made by marginalized people for inclusion into established oppressed identity groups must be constructed with due care to avoid further marginalizing yet other liminal identities; (2) protesting/boycotting other oppressed groups for the purpose of achieving inclusion is often a problematic strategy; (3) the most effective strategy for honoring all people is to support organizations committed to the ideal of inclusion.

Broad accommodation of rift-related extension recorded by dyke intrusion in Saudi Arabia

USGS Publications Warehouse

Pallister, J.S.; McCausland, W.A.; Jonsson, Sigurjon; Lu, Z.; Zahran, H.M.; El, Hadidy S.; Aburukbah, A.; Stewart, I.C.F.; Lundgren, P.R.; White, R.A.; Moufti, M.R.H.

2010-01-01

The extensive harrat lava province of Arabia formed during the past 30 million years in response to Red Sea rifting and mantle upwelling. The area was regarded as seismically quiet, but between April and June 2009 a swarm of more than 30,000 earthquakes struck one of the lava fields in the province, Harrat Lunayyir, northwest Saudi Arabia. Concerned that larger damaging earthquakes might occur, the Saudi Arabian government evacuated 40,000 people from the region. Here we use geologic, geodetic and seismic data to show that the earthquake swarm resulted from magmatic dyke intrusion. We document a surface fault rupture that is 8 km long with 91 cm of offset. Surface deformation is best modelled by the shallow intrusion of a north-west trending dyke that is about 10 km long. Seismic waves generated during the earthquakes exhibit overlapping very low- and high-frequency components. We interpret the low frequencies to represent intrusion of magma and the high frequencies to represent fracturing of the crystalline basement rocks. Rather than extension being accommodated entirely by the central Red Sea rift axis, we suggest that the broad deformation observed in Harrat Lunayyir indicates that rift margins can remain as active sites of extension throughout rifting. Our analyses allowed us to forecast the likelihood of a future eruption or large earthquake in the region and informed the decisions made by the Saudi Arabian government to return the evacuees.

Geochemistry of a Triassic dyke swarm in the North Patagonian Massif, Argentina. Implications for a postorogenic event of the Permian Gondwanide orogeny

NASA Astrophysics Data System (ADS)

González, Santiago N.; Greco, Gerson A.; González, Pablo D.; Sato, Ana M.; Llambías, Eduardo J.; Varela, Ricardo

2016-10-01

Permo-Triassic magmatism is widespread in the eastern North Patagonian Massif and has been related to the Gondwanide orogeny. Although a magmatic arc setting is widely accepted for the Permian plutonic rocks, the origin and geotectonic setting for the Triassic plutonic and volcanic rocks are still unknown. A NW-SE Triassic dyke swarm composed of andesites and latites with minor rhyolites was previously described in the Sierra Grande - Rincon de Paileman area. The dyke swarm was associated with extensional tectonics which was linked to a postorogenic process. In this paper we present new geochemical data of the rocks that form the swarm. Trachyandesites and rhyolites were separated based on their geochemical characteristics. Both groups may be considered originated from different sources. On the other hand, the content of incompatible elements (LILE and HFSE) indicates a strong relation between the swarm and an active continental margin. The samples also show a transitional signature between continental-arc and postcollisional or anorogenic settings. The new geochemical data on the dyke swarm support the idea of a magmatism that was linked to a postorogenic extensional tectonic regime related to a continental magmatic arc. Such an extension started in the Paleopacific margin of Pangea during the Anisian and might indicate the beginning of the Pangea break-up.

Dyke-Davidoff-Masson Syndrome. An unusual cause of status epilepticus.

PubMed

Zawar, Ifrah; Khan, Ashfa A; Sultan, Tipu; Rathore, Ahsan W

2015-10-01

The Dyke-Davidoff-Masson Syndrome (DDMS) results from an insult to the growing brain in utero or early infancy, which lead to loss of neurons compromising the growth of the brain. Clinical presentation includes seizures, hemiparesis, facial asymmetry, and learning disability. Radiological findings include cerebral atrophy on one side. Here, we present a case with status epilepticus who had underlying DDMS. It is a rare syndrome and uncommon cause for status epilepticus. Infections of CNS, hypoxic ischemic encephalopathy, intracranial bleed, trauma, congenital vascular malformations are the common causes of this syndrome. Diagnosis is established after clinical history, examination, and MRI. Intractable seizures can be controlled with appropriate anticonvulsants. Subsequently, these children may require physiotherapy, speech therapy, and occupational therapy in addition to the anticonvulsant medication. Outcome is better if the seizures are controlled.

Petrology, geochronology and emplacement model of the giant 1.37 Ga arcuate Lake Victoria Dyke Swarm on the margin of a large igneous province in eastern Africa

NASA Astrophysics Data System (ADS)

Mäkitie, Hannu; Data, Gabriel; Isabirye, Edward; Mänttäri, Irmeli; Huhma, Hannu; Klausen, Martin B.; Pakkanen, Lassi; Virransalo, Petri

2014-09-01

A comprehensive description of the petrography, geochemical composition, Sm-Nd data and intrinsic field relationships of a giant arcuate Mesoproterozoic mafic dyke swarm in SW Uganda is presented for the first time. The swarm is ∼100 km wide and mainly hosted in the Palaeoproterozoic Rwenzori Belt between the Mesoproterozoic Karagwe-Ankole Belt and the Archaean Uganda Block. The dykes trend NW-SE across Uganda, but can be correlated across Lake Victoria to another set of arcuate aeromagnetic anomalies that continue southwards into Tanzania, resulting in a remarkably large semi-circular swarm with an outer diameter of ∼500 km. We propose that this unique giant dyke structure be named the Lake Victoria Dyke Swarm (LVDS). The dykes are tholeiites with Mg numbers between 0.69 and 0.44, and with inherited marked negative Nb and P anomalies in spider diagrams. Two dykes provide Sm-Nd mineral ages of 1368 ± 41 Ma and 1374 ± 42 Ma, with initial εNd values of -2.3 and -3.2, and 87Sr/86Sr ratios of ∼0.706-0.709. Geotectonic discrimination diagrams for the swarm exhibit more arc type than within-plate tectonic signatures, but this is in accordance with systematic enrichments in LREE, U and Th in the dolerites, more likely due to the involvement of the continental lithosphere during their petrogenesis. The LVDS is coeval with a regional ∼1375 Ma bimodal magmatic event across nearby Burundi, Rwanda and NW Tanzania, which can collectively be viewed as a large igneous province (LIP). It also indicates that the nearby Karagwe-Ankole Belt sequences - bracketed between 1.78 and 1.37 Ga and assumed by some to have been deposited within intracratonic basins - were capped by flood basalts that have subsequently been removed by erosion. Different geochemical signatures (e.g. LaN/SmN) suggest that most of the arcuate swarm was derived from an enriched SCLM, whereas related intrusions in the centre of this semi-circular segment have more or less enriched asthenospheric mantle

Petrogenesis of Cretaceous (133-84 Ma) intermediate dykes and host granites in southeastern China: Implications for lithospheric extension, continental crustal growth, and geodynamics of Palaeo-Pacific subduction

NASA Astrophysics Data System (ADS)

Yang, Jinbao; Zhao, Zhidan; Hou, Qingye; Niu, Yaoling; Mo, Xuanxue; Sheng, Dan; Wang, Lili

2018-01-01

This paper presents U-Pb zircon geochronology, petrology, and major and trace element, Sr-Nd and zircon Hf isotopic geochemistry of Cretaceous granites and intermediate dykes in the Quanzhou and Xiamen regions of southeastern China. These data are used to investigate igneous petrogenesis and Cretaceous tectonic evolution, and interpret the geodynamics of Palaeo-Pacific slab subduction. Granites in Quanzhou and Xiamen range in age from 133 Ma to 87 Ma, have high SiO2 and K2O contents, low abundances in P2O5, and an A/CNK index that ranges from 0.97 to 1.09, indicating that they are high-K calc-alkaline metaluminous I-type rocks. Slightly negative ɛ Nd (t) values (- 1.2 to - 4.4), young Nd model ages (0.87 Ga to 1.20 Ga) and positive ɛ Hf (t) values (- 0.5 to + 9.9) of zircon grains indicate that the granites were derived from magmas that melted amphibolite in the middle-lower crust, and which may have assimilated country rocks during emplacement in shallow chambers. The intermediate dykes have no genetic link to the granites and magma mixing was negligible. Eight dyke samples have low SiO2 and high MgO, Ni and Cr contents. Negative ε Nd (t) values (- 1.5 to - 2.7) and positive ε Hf (t) values (2.7 to 7.6) suggest that the dykes were derived from residual basic lower crust after mafic-crystal accumulation. Two samples of adakite-like dykes are characterised by high Sr/Y ratios (89 to 100) and high SiO2, low K2O, Ni, Cr contents. In combination with slightly negative ε Nd (t) values (- 1.7 to - 1.8) and positive ε Hf (t) values (2.9 to 4.3), the adakite-like dykes were derived from cumulate basic lower crust which had a mixed source between depleted mantle- and crust-derived melts. Based on our data, combined with previously published work, we suggest that extension-induced middle-lower crustal melting and underplating of mantle-derived basaltic melts were the principal driving mechanisms for Cretaceous granitic magmatism in coastal Fujian Province. Extension

Associations of the Van Dyke's salamander (Plethodon vandykei) with geomorphic conditions in headwall seeps of the Cascade Range, Washington State.

Treesearch

A.P. McIntyre; R.A. Schmitz; C.M. Crisafulli

2006-01-01

We explored the association between Van Dyke's salamander (Plethodon vandykei) and hydrologic condition, geomorphology, and vegetation structure in headwall seeps in the Cascade Range of Washington State. We modeled occurrence of P. vandykei at three site scales: between seeps, within seeps, and between microhabitat sites...

Analysis of the deconstruction of Dyke Marsh, George Washington Memorial Parkway, Virginia-Progression, geologic and manmade causes, and effective restoration scenarios

USGS Publications Warehouse

Litwin, Ronald J.; Smoot, Joseph P.; Pavich, Milan J.; Markewich, Helaine W.; Oberg, Erik; Helwig, Ben; Steury, Brent; Santucci, Vincent L.; Durika, Nancy J.; Rybicki, Nancy B.; Engelhardt, Katharina M.; Sanders, Geoffrey; Verardo, Stacey; Elmore, Andrew J.; Gilmer, Joseph

2011-01-01

Photoanalysis of time-sequence aerial photographs of Dyke Marsh enabled us to calculate shoreline erosion estimates for this marsh over 19 years (1987-2006), as well as to quantify overall marsh acreage for 6 calendar years spanning an ~70 year interval (1937-2006). Photo overlay of a historic map enabled us to extend our whole-marsh acreage calculations back to 1883. Both sets of analyses were part of a geologic framework study in support of current efforts by the National Park Service (NPS) to restore this urban wetland. Two time intervals were selected for our shoreline erosion analyses, based on image quality and availability: 1987 to 2002, and 2002 to 2006. The more recent time interval shows a marked increase in erosion in the southern part of Dyke Marsh, following a wave-induced breach of a small peninsula that had protected its southern shoreline. Field observations and analyses of annual aerial imagery between 1987 and 2006 revealed a progressive increase in wave-induced erosion that presently is deconstructing Hog Island Gut, the last significant tidal creek network within the Dyke Marsh. These photo analyses documented an overall average westward shoreline loss of 6.0 to 7.8 linear feet per year along the Potomac River during this 19-year time interval. Additionally, photographic evidence documented that lateral erosion now is capturing existing higher order tributaries in the Hog Island Gut. Wave-driven stream piracy is fragmenting the remaining marsh habitat, and therefore its connectivity, relatively rapidly, causing the effective mouth of the Hog Island Gut tidal network to retreat headward visibly over the past several decades. Based on our estimates of total marsh area in the Dyke Marsh derived from 1987 aerial imagery, as much as 12 percent of the central part of the marsh has eroded in the 19 year period we studied (or ~7.5 percent of the original ~78.8 acres of 1987 marshland). Shoreline loss estimates for marsh parcels north and south of our

The carbonatite-marble dykes of Abyan Province, Yemen Republic: the mixing of mantle and crustal carbonate materials revealed by isotope and trace element analysis

NASA Astrophysics Data System (ADS)

Le Bas, M. J.; Ba-Bttat, M. A. O.; Taylor, R. N.; Milton, J. A.; Windley, B. F.; Evins, P. M.

2004-09-01

Dykes of carbonate rocks, that cut gneisses in the Lowder-Mudiah area of southern Yemen, consist of dolomite and/or calcite with or without apatite, barite and monazite. Petrographic observations, mineralogical, XRF and ICP-MS analyses reveal that some of the carbonate rocks are derived from sedimentary protoliths, whereas others are magmatic calcio- and magnesio-carbonatites some of which are mineralized with barite-monazite. The interbanded occurrence and apparent contemporary emplacement of these different rock types within individual dykes, backed by Sr Nd isotope evidence, are interpreted to show that intrusion of mantle-derived carbonatite magma was accompanied by mobilization of crustal marbles. That took place some 840 Ma ago but the REE-mineralization is dated at ca. 400 Ma.

Feasibility of Implementation of a Parenting Intervention with Karen Refugees Resettled from Burma.

PubMed

Ballard, Jaime; Wieling, Elizabeth; Forgatch, Marion

2018-04-01

Parents and children exposed to war and relocation have high rates of negative relational and mental health outcomes. This study tested the feasibility of implementing an adapted evidence-based parenting intervention for contexts of trauma and relocation stress. Eleven Karen refugee caregivers from Burma participated in the intervention. Participants and a focal child completed ethnographic interviews as well as structured assessments at baseline and follow-up. Caregivers reported changes in their teaching, directions, emotional regulation, discipline, and child compliance. Children reported changes in these areas and in positive parent involvement. Caregivers reported higher mental health distress immediately after the intervention, potentially due to increased awareness. Researchers made personalized referrals for counseling services as needed. Children reported a decrease in mental health symptoms. © 2017 American Association for Marriage and Family Therapy.

Contemporaneous alkaline and tholeiitic magmatism in the Ponta Grossa Arch, Paraná-Etendeka Magmatic Province: Constraints from U-Pb zircon/baddeleyite and 40Ar/39Ar phlogopite dating of the José Fernandes Gabbro and mafic dykes

NASA Astrophysics Data System (ADS)

Almeida, Vidyã V.; Janasi, Valdecir A.; Heaman, Larry M.; Shaulis, Barry J.; Hollanda, Maria Helena B. M.; Renne, Paul R.

2018-04-01

We report the first high-precision ID-TIMS U-Pb baddeleyite/zircon and 40Ar/39Ar step-heating phlogopite age data for diabase and lamprophyre dykes and a mafic intrusion (José Fernandes Gabbro) located within the Ponta Grossa Arch, Brazil, in order to constrain the temporal evolution between Early Cretaceous tholeiitic and alkaline magmatism of the Paraná-Etendeka Magmatic Province. U-Pb dates from chemically abraded zircon data yielded the best estimate for the emplacement ages of a high Ti-P-Sr basaltic dyke (133.9 ± 0.2 Ma), a dyke with basaltic andesite composition (133.4 ± 0.2 Ma) and the José Fernandes Gabbro (134.5 ± 0.1 Ma). A 40Ar/39Ar phlogopite step-heating age of 133.7 ± 0.1 Ma from a lamprophyre dyke is identical within error to the U-Pb age of the diabase dykes, indicating that tholeiitic and alkaline magmatism were coeval in the Ponta Grossa Arch. Although nearly all analysed fractions are concordant and show low analytical uncertainties (± 0.3-0.9 Ma for baddeleyite; 0.1-0.4 Ma for zircon; 2σ), Pb loss is observed in all baddeleyite fractions and in some initial zircon fractions not submitted to the most extreme chemical abrasion treatment. The resulting age spread may reflect intense and continued magmatic activity in the Ponta Grossa Arch.

Fluid Inclusion Study of Quartz Xenocrysts in Mafic Dykes from Kawant Area, Chhota Udaipur District, Gujarat, India

NASA Astrophysics Data System (ADS)

Randive, Kirtikumar; Hurai, Vratislav

2015-09-01

Unusual mafic dykes occur in the proximity of the Ambadongar Carbonatite Complex, Lower Narmada Valley, Gujarat, India. The dykes contain dense population of quartz xenocrysts within the basaltic matrix metasomatised by carbonate-rich fluids. Plagioclase feldspars, relict pyroxenes, chlorite, barite, rutile, magnetite, Fe-Ti oxides and glass were identified in the basaltic matrix. Quartz xenocrysts occur in various shapes and sizes and form an intricate growth pattern with carbonates. The xenocrysts are fractured and contain several types of primary and secondary, single phase and two-phase fluid inclusions. The two-phase inclusions are dominated by aqueous liquid, whereas the monophase inclusions are composed of carbonic gas and the aqueous inclusions homogenize to liquid between 226°C and 361°C. Majority of the inclusions are secondary in origin and are therefore unrelated to the crystallization of quartz. Moreover, the inclusions have mixed carbonic-aqueous compositions that inhibit their direct correlation with the crustal or mantle fluids. The composition of dilute CO2-rich fluids observed in the quartz xenocrysts appear similar to those exsolved during the final stages of evolution of the Amba Dongar carbonatites. However, the carbonates are devoid of fluid inclusions and therefore their genetic relation with the quartz xenocrysts cannot be established.

U-Pb baddeleyite ages and geochemistry of dolerite dykes in the Bas Drâa Inlier of the Anti-Atlas of Morocco: Newly identified 1380 Ma event in the West African Craton

NASA Astrophysics Data System (ADS)

El Bahat, Abdelhakim; Ikenne, Moha; Söderlund, Ulf; Cousens, Brian; Youbi, Nasrrddine; Ernst, Richard; Soulaimani, Abderrahmane; El Janati, M'hamed; Hafid, Ahmid

2013-08-01

In the Bas-Drâa Inlier (Anti-Atlas, Morocco), the Paleoproterozoic basement which is cut by the Ediacaran Taourgha granite is also crosscut by numerous dykes of a variety of trends, mostly of uncertain age. Two doleritic dykes are dated by the ID-TIMS U-Pb method on baddeleyite and yield emplacement ages of 1381 ± 8 Ma (MSWD = 0.84) and 1384 ± 6 Ma (MSWD = 1.4) determined for a N135°E and a N40°E trending dyke, respectively. These dates represent the first geochronological evidence of a Mesoproterozoic magmatic event in the Anti-Atlas. This magmatic event falls in the previously considered ca 1.7-1.0 Ga (Mesoproterozoic) gap in geological activity in the Anti-Atlas. The poorly dated Taghdout and Taarotihate sequences could represent remnants of the ca. 1380 Ma magmatism and rift-related sedimentation. The Mesoproterozoic sedimentary succession of the Atar Group in the Taoudeni basin (Mauritania) could also represent a good candidate for rift-related sedimentation but it postdates the 1380 Ma magmatic event by 270 Ma. The dated 1380 Ma dykes are transitional to mildly alkaline basalts, not unlike some Hawaiian lavas. However, these dykes have a distinct negative Nb anomaly (a common features in many Large Igneous Provinces, LIPs), and this requires interaction with the lithosphere. This interaction may have occurred at the level of the lithospheric mantle or the crust. These newly dated 1380 Ma dykes may converge to the north, speculatively suggesting a magmatic center (associated with a 1380 Ma mantle plume?) along the northern margin, and possibly linked to rifting and possible breakup on that margin, and also to a regional uplift that largely removed the evidence of a 1380 Ma cover sequence. Contemporaneous 1380-1390 Ma magmatism is reported elsewhere on other crustal blocks, and that in northeastern Laurentia (northern Greenland), northern Siberia (Anabar shield), and Baltica (southern Urals) can be reconstructed with that of the Bas Drâa Inlier (Anti

U-Pb geochronology and paleomagnetism of the Neoproterozoic St Simeon dolerite dykes, Quebec: an eastern Laurentian perspective of Ediacaran Rodinia breakup

NASA Astrophysics Data System (ADS)

Pisarevsky, Sergei; Murphy, Brendan; Hamilton, Mike; Söderlund, Ulf; Hodych, Joseph

2013-04-01

The St Simeon (SS) mafic dykes (150 km NE of Quebec City) are now dated at 548 ± 1 Ma (U-Pb; baddeleyite). This age is similar to a published LA-ICPMS zircon age of 550 ± 7 Ma for the Mt. St-Anselme (MS) basalts, which supports previous inferences of (i) a genetic relationship between them, (ii) the pene-contemporaneity of OIB-type mafic magmatism in East Laurentia and (iii) the existence of two late Ediacaran plumes that attended the final breakup of Rodinia and opening of the Iapetus Ocean and Tornquist Sea. Both the SS dykes and the MS basalts were sampled for paleomagnetic study. The paleomagnetic pole for SS is similar to the previously published pole for coeval basalts (Skinner Cove, SC) from Newfoundland. Unlike SC, the St Simeon pole represents rocks which are unambiguously coherent tectonically with the Laurentian Craton. This new pole is also coeval with high quality poles from the Winter Coast (Baltica) and provides paleomagnetic constraints on the history of the final breakup of Rodinia and opening of Eastern Iapetus and Tornquist Sea.

Major and trace element, and Sr isotope compositions of clinopyroxene phenocrysts in mafic dykes on Jiaodong Peninsula, southeastern North China Craton: Insights into magma mixing and source metasomatism

NASA Astrophysics Data System (ADS)

Liang, Yayun; Deng, Jun; Liu, Xuefei; Wang, Qingfei; Qin, Cheng; Li, Yan; Yang, Yi; Zhou, Mian; Jiang, Jieyan

2018-03-01

Early Cretaceous mafic dyke swarms are widely developed on Jiaodong Peninsula in the southeastern part of the North China Craton (NCC), but their petrogenesis remains enigmatic. We have examined the in-situ major element, trace element and Sr isotope compositions of the clinopyroxene phenocrysts in these dykes in order to evaluate the extent of magma mixing and source metasomatism. Depending on the type of mineral zoning, the clinopyroxene phenocrysts in our samples can be classified into two groups: Group I (reverse zoning) and Group II (no zoning). Based on core compositions, the Group I phenocrysts with obvious reverse zoning can be divided into two subgroups: Groups IA and IB. The cores of Group IA clinopyroxenes have low values of Mg#, low Al2O3 contents, high Na2O contents, and high 87Sr/86Sr ratios, and they were probably derived from newly accreted lower crust that formed through the underplating of basaltic magma. In contrast, the cores of Group IB clinopyroxenes have lower Mg# values and lower contents of Al2O3, ΣREE (total rare earth elements), and incompatible elements, but they have similar 87Sr/86Sr ratios; these cores crystallised from crust-derived andesitic-dacitic magma. Group IA and IB clinopyroxene phenocryst rims (Group I rims) all have similar compositions with higher values of Mg# and higher Al2O3, Cr and Ni contents than the cores. The rims have high 87Sr/86Sr ratios, are enriched in LREEs (light rare earth elements) and LILEs (large ion lithophile elements), and are depleted in HFSEs (high field strength elements); these characteristics indicate that all the high-Mg rims were derived from a similar magma, possibly a relatively primitive magma derived from lithospheric mantle. We suggest, therefore, that the reversely-zoned clinopyroxene phenocrysts (Group I) in the Jiaodong mafic dykes provide evidence of magma mixing between a magma derived from lithospheric mantle and crust-derived andesitic-dacitic melt alongside with the newly accreted

Impacts of dyke development in flood prone areas in the Vietnamese Mekong Delta to downstream flood hazard

NASA Astrophysics Data System (ADS)

Khanh Triet Nguyen, Van; Dung Nguyen, Viet; Fujii, Hideto; Kummu, Matti; Merz, Bruno; Apel, Heiko

2016-04-01

The Vietnamese Mekong Delta (VMD) plays an important role in food security and socio-economic development of the country. Being a low-lying coastal region, the VMD is particularly susceptible to both riverine and tidal floods, which provide, on (the) one hand, the basis for the rich agricultural production and the livelihood of the people, but on the other hand pose a considerable hazard depending on the severity of the floods. But despite of potentially hazardous flood, the area remain active as a rice granary due to its nutrient-rich soils and sediment input, and dense waterways, canals and the long standing experience of the population living with floods. In response to both farmers' requests and governmental plans, the construction of flood protection infrastructure in the delta progressed rapidly in the last twenty years, notably at areas prone to deep flooding, i.e. the Plain of Reeds (PoR) and Long Xuyen Quadrangle (LXQ). Triple rice cropping becomes possible in farmlands enclosed by "full-dykes", i.e. dykes strong and high enough to prevent flooding of the flood plains for most of the floods. In these protected flood plains rice can be grown even during the peak flood period (September to November). However, little is known about the possibly (and already alleged) negative impacts of this fully flood protection measure to downstream areas. This study aims at quantifying how the flood regime in the lower part of the VMD (e.g. Can Tho, My Thuan, …) has been changed in the last 2 recent "big flood" events of 2000 and 2011 due to the construction of the full-dyke system in the upper part. First, an evaluation of 35 years of daily water level data was performed in order to detect trends at key gauging stations: Kratie: upper boundary of the Delta, Tan Chau and Chau Doc: areas with full-dyke construction, Can Tho and My Thuan: downstream. Results from the Mann-Kendall (MK) test show a decreasing trend of the annual maximum water level at 3 stations Kratie, Tan

Modelling of The Dyke Emplacement Leading To The Etna July 2001 Eruption Through Continuous Tilt and GPS Data

NASA Astrophysics Data System (ADS)

Bonaccorso, A.; Aloisi, M.; Mattia, A.

During the June 2001 eruption of Mt. Etna the continuous ground deformation mon- itoring have been recorded through tilt (9 stations) and GPS (11 stations) permanent networks. The evolution of the July crisis preceding and leading to the eruption has been monitored through the tilt and GPS continuous measurements, which constrained in time the final intrusion and inferred the position and geometry of the uprising dyke. The tilt signals, which record 48 samples/day, fixed the time action of the intrusion, whose main effects are recorded during 13-15 July in concomitance with the first days of the seismic crisis. In particular, the high precision long-base mercury tiltmeter, in- stalled at Pizzi Deneri observatory in the high north-eastern flank close to the crater area, showed very well the continuous deformation during the dyke emplacement. The deformation pattern, at the entire volcano scale, was well characterised by the daily measurement sessions recorded at the GPS permanent network. The variations recorded at the permanent GPS stations started from July 13 and, in agreement with tilt recordings, were mainly cumulated in the following two days. The GPS measurements showed horizontal displacement vectors much bigger than vertical changes. The defor- mation pattern indicates the response to a tensile mechanisms that appears compatible with an intrusion in the volcano edifice along a ca. N-S direction. In this poster we show the modelling of the marked ground deformation changes recorded in the days before the eruption starting. The first results show that a tensile crack with an opening dislocation of ~3 m. and crossing the entire edifice, south-west to the crater area, can explain the recorded deformation pattern. The location of the modelled tensile source fits the seismogenetic zone characterized by epicenters aligned in a ca. N-S direction with the foci clustered in the last shallow kilometers. The ground deformation pat- tern associated with the final

Extremely high sulfate reduction, sediment oxygen demand and benthic nutrient flux associated with a large-scale artificial dyke and its implication to benthic-pelagic coupling in the Yeongsan River estuary, Yellow Sea.

PubMed

Kim, Sung-Han; Lee, Jae Seong; Hyun, Jung-Ho

2017-07-15

We investigated environmental impact of large-scale dyke on the sediment geochemistry, sulfate reduction rates (SRRs), sediment oxygen demand (SOD) and potential contribution of benthic nutrient flux (BNF) to primary production in the Yeongsan River estuary, Yellow Sea. The sediment near the dyke (YE1) with high organic carbon (C org ) content (>4%, dry wt.) was characterized by extremely high SOD (327mmolm -2 d -1 ) and SRRs (91-140mmolm -2 d -1 ). The sulfate reduction accounted for 73% of C org oxidation, and was responsible for strikingly high concentrations of NH 4 + (7.7mM), PO 4 3- (67μM) and HS - (487μM) in pore water. The BNF at YE1 accounted for approximately 200% of N and P required for primary production in the water column. The results present one of the most extreme cases that the construction of an artificial dyke may have profound impacts on the biogeochemical and ecological processes in coastal ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

On precisely modelling surface deformation due to interacting magma chambers and dykes

NASA Astrophysics Data System (ADS)

Pascal, Karen; Neuberg, Jurgen; Rivalta, Eleonora

2014-01-01

Combined data sets of InSAR and GPS allow us to observe surface deformation in volcanic settings. However, at the vast majority of volcanoes, a detailed 3-D structure that could guide the modelling of deformation sources is not available, due to the lack of tomography studies, for example. Therefore, volcano ground deformation due to magma movement in the subsurface is commonly modelled using simple point (Mogi) or dislocation (Okada) sources, embedded in a homogeneous, isotropic and elastic half-space. When data sets are too complex to be explained by a single deformation source, the magmatic system is often represented by a combination of these sources and their displacements fields are simply summed. By doing so, the assumption of homogeneity in the half-space is violated and the resulting interaction between sources is neglected. We have quantified the errors of such a simplification and investigated the limits in which the combination of analytical sources is justified. We have calculated the vertical and horizontal displacements for analytical models with adjacent deformation sources and have tested them against the solutions of corresponding 3-D finite element models, which account for the interaction between sources. We have tested various double-source configurations with either two spherical sources representing magma chambers, or a magma chamber and an adjacent dyke, modelled by a rectangular tensile dislocation or pressurized crack. For a tensile Okada source (representing an opening dyke) aligned or superposed to a Mogi source (magma chamber), we find the discrepancies with the numerical models to be insignificant (<5 per cent) independently of the source separation. However, if a Mogi source is placed side by side to an Okada source (in the strike-perpendicular direction), we find the discrepancies to become significant for a source separation less than four times the radius of the magma chamber. For horizontally or vertically aligned pressurized

Neurosyphilis, or chronic heavy metal poisoning: Karen Blixen's lifelong disease.

PubMed

Weismann, K

1995-01-01

Since the 1490s, the treatment of syphilis has consisted of heavy metals--first mercurial and later arsenic and bismuth preparations. Tabes dorsalis, as described by Duchenne in the 1850s, is made up of various characteristic neurologic symptoms. "Gastric crises," sudden stabbing pains followed by vomiting and diarrhea, was originally included by Duchenne, but later, syphilologists disputed its relevance to syphilis. Poisoning by heavy metals, including mercury, may produce similar pain reactions and tabes-like neurologic symptoms. According to an earlier published pathography, the Danish author Karen Blixen (1885-1962), also known under the pseudonym Isak Dinesen, suffered from a lifelong disease described as tabes dorsalis. She got syphilis in 1914 and took mercury pills for a year, after which she experienced a severe mercurial intoxication. The Wassermann reaction (WR) in peripheral blood was positive only once, in 1915, before treatment with arsphenamine (Salvarsan), which she received during hospitalization in Copenhagen in 1915 to 1916. Her spinal fluid was examined several times from 1915 to 1956. Apart from an increased number of cells in 1915, the fluid remained unremarkable and the WR was always negative. It was postulated that her illness, ending with a cachectic state, was the result of heavy metal poisoning from the various treatments and not a monosymptomatic tabes dorsalis with negative serology.

Carbonatitic dykes during Pangaea transtension (Pelagonian Zone, Greece)

NASA Astrophysics Data System (ADS)

Schenker, Filippo Luca; Burg, Jean-Pierre; Kostopoulos, Dimitrios; Baumgartner, Lukas P.; Bouvier, Anne-Sophie

2018-03-01

Carbonatitic dykes surrounded by K-Na-fenites were discovered in the Pelagonian Zone in Greece. Their carbonate portions have an isotopic mantle signature of δ13C and δ18O ranging from -5.18 to -5.56 (‰ vs. VPDB) and from 10.68 to 11.59 (‰ vs. VSMOW) respectively, whereas their mafic silicate portions have high Nb, Ta and ɛNd values, typical of alkaline basalts. Textural relationships hint at a cogenetic intrusion of silicate and carbonate liquids that according to antithetic REE profiles segregated at shallow depths (<0.6 GPa) from a parental melt sourced deeper in the mantle. Fenites bear similar REE abundances to mafic rocks but with high Rb-Ba and low Nb-Ta values. SHRIMP II U-Pb analyses of magmatic zircon cores (δ18O = 7.21-7.51) from a carbonate-bearing syenitic amphibolite yielded a Permian intrusion age at 278 ± 2 Ma, considerably older than a Cretaceous (118 ± 4 Ma) greenschist overprint obtained from metamorphic zircon rims (δ18O = 6.78-7.02). From 300 to 175 Ma the ɛNd of the Pelagonian magmatism rose irregularly to more primitive values attesting to a higher increment of asthenosphere-derived melts. In this context, the carbonatite formed within a transtensional regime of an intra-Pangaea dextral transform fault that signalled the forthcoming penetrating breakoff of the supercontinent, manifested in the Permo-Triassic.

Mineralogy and geochemistry of picro-dolerite dykes from the central Deccan Traps flood basaltic province, India, and their geodynamic significance

NASA Astrophysics Data System (ADS)

Dongre, Ashish; Viljoen, K. S.; Rathod, A.

2018-04-01

Constituent mineral compositions and whole rock major element geochemistry of picro-dolerite dykes from the central part of the Deccan flood basalt province are presented and discussed. The dykes are characterized by an MgO content of about 13 wt%, coupled with 13-16 modal percents of olivine. A high whole rock molar Mg# value of 71 and the presence of magnesian olivine phenocrysts ( Fo78) are consistent with a primitive (i.e. unevolved) geochemistry. The nature and composition of clinopyroxene (augite and pigeonite), plagioclase feldspar (labradorite) and Fe-Ti oxides (mostly ilmenite and magnetite) are also discussed, with implications drawn with respect to the geodynamics. High MgO magmas and rocks such as picrites are generally considered to be indicative of plume magmatism, formed by high degrees of partial melting in, e.g. the high-temperature region of a plume head. Recent age data is consistent with a model in which the Deccan LIP picritic magmatism is associated with the main phase of Deccan Trap activity at 66 Ma, as a result of a syn- to post rifting phase associated with the impact of the Rèunion mantle plume. It is speculated that the differentiation of primary olivine basaltic magma of picritic composition, may have been the mechanism for the generation of alkalic basalts which occurs in the Deccan Trap basaltic sequence.

Seismic constraints on a large dyking event and initiation of a transform fault zone in Western Gulf of Aden

NASA Astrophysics Data System (ADS)

Ahmed, AbdulHakim; Doubre, Cecile; Leroy, Sylvie; Perrot, Julie; Audin, Laurence; Rolandone, Frederique; Keir, Derek; Al-Ganad, Ismael; Sholan, Jamal; Khanbari, Khaled; Mohamed, Kassim; Vergne, Jerome; Jacques, Eric; Nercessian, Alex

2013-04-01

In November 2010, a large number of events were recorded by the world seismic networks showing important activity occurring along the western part of the Aden Ridge. West of the Shulka El Sheik fracture zone, events in this large seismic swarm (magnitudes above 5) occurred in a complex area, where the change of both the ridge direction and the bathymetry suggest the propagation of the ridge into a continental lithosphere and the influence of the Afar plume. We combine several sets of data from permanent networks and temporary 3C broad stations installed after the beginning of the event along the southern and eastern coasts of Yemen and Djibouti respectively, we located more than 600 earthquakes with magnitudes ranging from 2.5 to 5.6 that occurred during the first months following the first event. The spatial distribution of the main seismicity reveals a very clear N115° -trending alignment, parallel to the mean direction of the en-echelon spreading segments that form the ridge at this longitude. Half of the events, which represent half of the total seismic energy released during the first months, are located in the central third section of the segment. Here several volcanic cones and recent lava flows observed from bathymetric and acoustic reflectivity data during the Tadjouraden cruise (Audin, 1999, Dauteuil et al., 2001) constitute the sea floor. In addition to this main activity, two small groups of events suggest the activiation of landslides into a large fan and the activity in a volcanic area 50 km due east from the main active zone. The time evolution of the seismicity shows several bursts of activity. Some of them are clearly related to sudden activities within the volcanic areas, when others exhibit horizontal migration of the events, with velocity around ˜ 1 km/h. The time-space evolution of the seismicity clearly reveals the intrusion of dykes associated with magma propagation from the crustal magmatic centres into the rift zone. Taking into account

The avian community of the Karen Mogensen Reserve, a wealth of biodiversity within the poorly investigated and threatened environments of northwestern Costa Rica

PubMed Central

Zotto, Matteo Dal; Romeo, Giuseppe; Aguilar, Luis A. Mena; Sonetti, Dario; Pederzoli, Aurora

2017-01-01

Abstract Despite being characterized by some of the most threatened forest ecosystems of Mesoamerica, the Nicoya Peninsula is among the least known regions of neotropical Costa Rica in terms of its birdlife. Within this region, in the framework of an ongoing international cooperation program between Italy and Costa Rica, we had the opportunity to investigate the Karen Mogensen Reserve, a protected area distinguished by the presence of a variety of habitats, including tropical dry forest and moist forest. Species richness in the Reserve was relatively high compared with similar areas in northwestern Costa Rica. A series of surveys carried out over a 20-year period documented an avian community consisting of 207 species, of which 115 were breeding in the zone and another 14 were potentially breeding. We recorded five IUCN globally Vulnerable or Near-Threatened species, along with six species reported for the first time from the Nicoya Peninsula, each representing range extension of more than 100 km. Twenty-six species, mostly breeding in the area, are at their southernmost range borders, and are likely susceptible to global environmental alterations, such as the effects of climate change. Furthermore, our study revealed the presence of two species endemic to a restricted area of Central America and four subspecies endemic to Costa Rica, along with breeding populations of two species that are geographically isolated from the main ones. The present analysis led to the ecological characterization of the resident avian community, showing that 65% of the species are strictly associated with forested environments, and especially with the understory or middle tree level, hence more vulnerable to environmental change (climatic, anthropogenic, etc.) and susceptible to local extinction. These results underscore the importance of the Karen Mogensen Reserve for bird conservation within a vulnerable environmental context, and warrant the continuation of periodic bird surveys

The avian community of the Karen Mogensen Reserve, a wealth of biodiversity within the poorly investigated and threatened environments of northwestern Costa Rica.

PubMed

Zotto, Matteo Dal; Romeo, Giuseppe; Aguilar, Luis A Mena; Sonetti, Dario; Pederzoli, Aurora

2017-01-01

Despite being characterized by some of the most threatened forest ecosystems of Mesoamerica, the Nicoya Peninsula is among the least known regions of neotropical Costa Rica in terms of its birdlife. Within this region, in the framework of an ongoing international cooperation program between Italy and Costa Rica, we had the opportunity to investigate the Karen Mogensen Reserve, a protected area distinguished by the presence of a variety of habitats, including tropical dry forest and moist forest. Species richness in the Reserve was relatively high compared with similar areas in northwestern Costa Rica. A series of surveys carried out over a 20-year period documented an avian community consisting of 207 species, of which 115 were breeding in the zone and another 14 were potentially breeding. We recorded five IUCN globally Vulnerable or Near-Threatened species, along with six species reported for the first time from the Nicoya Peninsula, each representing range extension of more than 100 km. Twenty-six species, mostly breeding in the area, are at their southernmost range borders, and are likely susceptible to global environmental alterations, such as the effects of climate change. Furthermore, our study revealed the presence of two species endemic to a restricted area of Central America and four subspecies endemic to Costa Rica, along with breeding populations of two species that are geographically isolated from the main ones. The present analysis led to the ecological characterization of the resident avian community, showing that 65% of the species are strictly associated with forested environments, and especially with the understory or middle tree level, hence more vulnerable to environmental change (climatic, anthropogenic, etc.) and susceptible to local extinction. These results underscore the importance of the Karen Mogensen Reserve for bird conservation within a vulnerable environmental context, and warrant the continuation of periodic bird surveys, taxonomic

Seismic constraints on a large dyking event in Western Gulf of Aden

NASA Astrophysics Data System (ADS)

Ahmed, A.; Doubre, C.; Leroy, S.; Perrot, J.; Audin, L.; Rolandone, F.; Keir, D.; Al-Ganad, I.; Khanbari, K.; Mohamed, K.; Vergne, J.; Jacques, E.; Nercessian, A.

2012-04-01

In November 2010, a large number of events were recorded by the world seismic networks showing important activity occurring along the western part of the Aden Ridge. West of the Shulka El Sheik transform zone, events in this large seismic swarm (magnitudes above 5) occurred in a complex area, where the change of both the ridge direction and the bathymetry suggest the propagation of the ridge into a continental lithosphere and the influence of the thermal anomaly of the Afar Hot Spot. We combine several sets of data from permanent networks and temporary 3C broad stations installed after the beginning of the event along the southern and eastern coasts of Yemen and Djibouti respectively, we located more than 600 earthquakes with magnitudes ranging from 2.5 to 5.6 that occurred during the first months following the first event. The spatial distribution of the main seismicity reveals a very clear N115°-trending alignment, parallel to the mean direction of the en-echelon spreading segments that form the ridge at this longitude. Half of the events, which represent half of the total seismic energy released during the first months, are located in the central third section of the segment. Here several volcanic cones and recent lava flows observed from bathymetric and acoustic reflectivity data during the Tadjouraden cruise (Audin, 1999, Dauteuil et al., 2001) constitute the sea floor. In addition to this main activity, two small groups of events suggest the activiation of landslides into a large fan and the activity in a volcanic area 50 km due east from the main active zone. The time evolution of the seismicity shows several bursts of activity. Some of them are clearly related to sudden activities within the volcanic areas, when others exhibit horizontal migration of the events, with velocity around ~ 1 km/h. The time-space evolution of the seismicity clearly reveals the intrusion of dykes associated with magma propagation from the crustal magmatic centres into the rift

Microstructural Indicators Of Convection In Sills And Dykes

NASA Astrophysics Data System (ADS)

Holness, M. B.; Neufeld, J. A.; Gilbert, A. J.; Macdonald, R.

2016-12-01

The question of whether or not convection occurs in crustal magma chambers is a vexed one, with some advocating vigorous convection while others argue that convection is weak and short-lived. We argue that microstructural analysis is key to determining whether crystallization took place in solidification fronts or whether crystals grew suspended in a convecting magma before settling. The 168m, composite, Shiant Isles Main Sill is dominated by a 140m unit, of which the lower 45m contains olivine phenocrysts. The phenocrysts first fine upwards, then coarsen upwards. The coarsening-upwards sequence contains clustered olivines. Both the extent of sintering and average cluster size increase upwards. The coarsening-upwards sequence is mirrored at the roof. The fining-upwards sequence formed by rapid settling of incoming cargo crystals, while the coarsening-upwards sequence represents post-emplacement growth and clustering of grains suspended in a convecting magma. Convection is also recorded by plagioclase grain shape. Well-facetted and compact plagioclase grains are platy in rapidly-cooled rocks and blocky in slowly-cooled rocks. Plagioclase grain shape varies smoothly across mafic sills, consistent with growth in solidification fronts. In contrast, grain shape is invariant across mafic dykes, consistent with growth as individual grains and clusters suspended in a convecting magma. Convection in sills occurs when the critical Rayleigh number is exceeded, but cooling at vertical walls always results in convective instabilities. That the Shiant Isles Main Sill records prolonged and vigorous convection, while other sills of comparable thickness record grain growth predominantly in solidification fronts, is most likely due to the composite nature of the Shiant. The 140m unit is underlain by 23m of picrite which intruded shortly before - the strongly asymmetric cooling and absence of a cold, stagnant basal thermal boundary layer make convection throughout the sill more

Baseline characteristics of patients with heart failure and preserved ejection fraction included in the Karolinska Rennes (KaRen) study.

PubMed

Donal, Erwan; Lund, Lars H; Oger, Emmanuel; Hage, Camilla; Persson, Hans; Reynaud, Amélie; Ennezat, Pierre-Vladimir; Bauer, Fabrice; Sportouch-Dukhan, Catherine; Drouet, Elodie; Daubert, Jean-Claude; Linde, Cecilia

2014-02-01

Karolinska Rennes (KaRen) is a prospective observational study to characterize heart failure patients with preserved ejection fraction (HFpEF) and to identify prognostic factors for long-term mortality and morbidity. To report characteristics and echocardiography at entry and after 4-8 weeks of follow-up. Patients were included following an acute heart failure presentation with B-type natriuretic peptide (BNP)>100 ng/L or N-terminal pro-BNP (NT-proBNP)>300 ng/L and left ventricular ejection fraction (LVEF)>45%. The mean ± SD age of 539 included patients was 77 ± 9 years and 56% were women. Patient history included hypertension (78%), atrial tachyarrhythmia (44%), prior heart failure (40%) and anemia (37%), but left bundle branch block was rare (3.8%). Median NT-proBNP was 2448 ng/L (n=438), and median BNP 429 ng/L (n=101). Overall, 101 patients did not return for the follow-up visit, including 13 patients who died (2.4%). Apart from older age (80 ± 9 vs. 76 ± 9 years; P=0.006), there were no significant differences in baseline characteristics between patients who did and did not return for follow-up. Mean LVEF was lower at entry than follow-up (56% vs. 62%; P<0.001). At follow-up, mean E/e' was 12.9 ± 6.1, left atrial volume index 49.4±17.8mL/m(2). Mean global left ventricular longitudinal strain was -14.6 ± 3.9%; LV mass index was 126.6 ± 36.2g/m(2). Patients in KaRen were old with slight female dominance and hypertension as the most prevalent etiological factor. LVEF was preserved, but with increased LV mass and depressed LV diastolic and longitudinal systolic functions. Few patients had signs of electrical dyssynchrony (ClinicalTrials.gov.- NCT00774709). Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Platinum-group element concentrations in pyrite from the Main Sulfide Zone of the Great Dyke of Zimbabwe

NASA Astrophysics Data System (ADS)

Piña, R.; Gervilla, F.; Barnes, S.-J.; Oberthür, T.; Lunar, R.

2016-10-01

The Main Sulfide Zone (MSZ) of the Great Dyke of Zimbabwe hosts the world's second largest resource of platinum-group elements (PGE) after the Bushveld Complex in South Africa. The sulfide assemblage of the MSZ comprises pyrrhotite, pentlandite, chalcopyrite, and minor pyrite. Recently, several studies have observed in a number of Ni-Cu-PGE ore deposits that pyrite may host significant amounts of PGE, particularly Pt and Rh. In this study, we have determined PGE and other trace element contents in pyrite from the Hartley, Ngezi, Unki, and Mimosa mines of the Great Dyke by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Based on the textures and PGE contents, two types of pyrite can be differentiated. Py1 occurs as individual euhedral or subhedral grains or clusters of crystals mostly within chalcopyrite and pentlandite, in some cases in the form of symplectitic intergrowths, and is PGE rich (up to 99 ppm Pt and 61 ppm Rh; 1.7 to 47.1 ppm Ru, 0.1 to 7.8 ppm Os, and 1.2 to 20.2 ppm Ir). Py2 occurs as small individual euhedral or subhedral crystals within pyrrhotite, pentlandite, and less frequently within chalcopyrite and silicates and has low PGE contents (<0.11 ppm Pt, <0.34 ppm Rh, <2.5 ppm Ru, <0.37 ppm Ir, and <0.40 ppm Os). Py1 contains higher Os, Ir, Ru, Rh, and Pt contents than the associated pyrrhotite, pentlandite, and chalcopyrite, whereas Py2 has similar PGE contents as coexisting pyrrhotite and pentlandite. Based on the textural relationships, two different origins are attributed for each pyrite type. Py1 intergrowth with pentlandite and chalcopyrite is inferred to have formed by late, low temperature (<300 °C) decomposition of residual Ni-rich monosulfide solid solution, whereas Py2 is suggested to have formed by replacement of pyrrhotite and pentlandite caused by late magmatic/hydrothermal fluids.

Textural, mineralogical and stable isotope studies of hydrothermal alteration in the main sulfide zone of the Great Dyke, Zimbabwe and the precious metals zone of the Sonju Lake Intrusion, Minnesota, USA

USGS Publications Warehouse

Li, C.; Ripley, E.M.; Oberthur, T.; Miller, J.D.; Joslin, G.D.

2008-01-01

Stratigraphic offsets in the peak concentrations of platinum-group elements (PGE) and base-metal sulfides in the main sulfide zone of the Great Dyke and the precious metals zone of the Sonju Lake Intrusion have, in part, been attributed to the interaction between magmatic PGE-bearing base-metal sulfide assemblages and hydrothermal fluids. In this paper, we provide mineralogical and textural evidence that indicates alteration of base-metal sulfides and mobilization of metals and S during hydrothermal alteration in both mineralized intrusions. Stable isotopic data suggest that the fluids involved in the alteration were of magmatic origin in the Great Dyke but that a meteoric water component was involved in the alteration of the Sonju Lake Intrusion. The strong spatial association of platinum-group minerals, principally Pt and Pd sulfides, arsenides, and tellurides, with base-metal sulfide assemblages in the main sulfide zone of the Great Dyke is consistent with residual enrichment of Pt and Pd during hydrothermal alteration. However, such an interpretation is more tenuous for the precious metals zone of the Sonju Lake Intrusion where important Pt and Pd arsenides and antimonides occur as inclusions within individual plagioclase crystals and within alteration assemblages that are free of base-metal sulfides. Our observations suggest that Pt and Pd tellurides, antimonides, and arsenides may form during both magmatic crystallization and subsolidus hydrothermal alteration. Experimental studies of magmatic crystallization and hydrothermal transport/deposition in systems involving arsenides, tellurides, antimonides, and base metal sulfides are needed to better understand the relative importance of magmatic and hydrothermal processes in controlling the distribution of PGE in mineralized layered intrusions of this type. ?? Springer-Verlag 2007.

Sediment dynamics over multiple time scales in Dyke Marsh Preserve (Potomac River, VA)

NASA Astrophysics Data System (ADS)

Palinkas, C. M.; Walters, D.

2010-12-01

Tidal freshwater marshes are critical components of fluvial and estuarine ecosystems, yet sediment dynamics within them have not received as much attention as their saltwater counterparts. This study examines sedimentation in Dyke Marsh Preserve, located on the Potomac River (VA), focusing on understanding the spatial variability present over multiple time scales. Bimonthly sediment data were collected using ceramic tiles, and seasonal- and decadal-scale sedimentation was determined via 7Be (half-life 53.3 days) and 210Pb (half-life 22.3 years), respectively. Results were also compared to SET data collected by the National Park Service since 2006. Preliminary data indicate that sites at lower elevations have higher sedimentation rates, likely related to their close proximity to the sediment source. Mass accumulation rates generally decreased with increasing time scale, such that the seasonal rates were greater than the SET-derived accretion rates, which were in turn greater than the decadal-scale rates. However, the bimonthly rates were the lowest observed, probably because the sampling period (May-October 2010) did not include the main depositional period of the year, which would be integrated by the other techniques.

Le magmatisme basique filonien néoprotérozoïque de la boutonnière de Zenaga, Anti-Atlas central, Maroc: pétrologie, géochimie et signification géodynamiqueNeoproterozoic basic dykes of the Zenaga Inlier, central Anti-Atlas, Morocco: petrology, geochemistry and geodynamic significance

NASA Astrophysics Data System (ADS)

Hafid, A.; Sagon, J. P.; Julivert, M.; Arboleya, M. L.; Saquaque, A.; El-Boukhari, A.; Saidi, A.; Soler, J. M. F.

2001-05-01

Before the Pan-African Orogeny, the Palæoproterozoic basement and its Neoproterozoic cover (limestones and quartzites) of the Zenaga Inlier were cross-cut by a swarm of doleritic dykes. They are more or less altered. The primary mineral assemblage consists of plagioclase, clinopyroxene, very rare orthopyroxene, ilmenite, apatite, micropegmatite and sometimes hornblende and biotite. Mineralogical and geochemical studies indicate that the dolerites are continental tholeiites. Two groups of dykes have been distinguished. Accordingly, rare earth elements, P 2O 5, Zr, Th, Ba and Sr contents are higher in group I than in group II, which is richer in V. Group I comprises the north-south and northwest-southeast swarms, while group II corresponds to northeast-southwest and east-west swarms, which were emplaced later. These geochemical variations may be explained by a higher degree of melting of the mantle source for the later group II. Doleritic dykes of Zenaga had been emplaced during an extensional episode, prior to Pan-African folding.

Estimated Flood-Inundation Mapping for the Upper Blue River, Indian Creek, and Dyke Branch in Kansas City, Missouri, 2006-08

USGS Publications Warehouse

Kelly, Brian P.; Huizinga, Richard J.

2008-01-01

In the interest of improved public safety during flooding, the U.S. Geological Survey, in cooperation with the city of Kansas City, Missouri, completed a flood-inundation study of the Blue River in Kansas City, Missouri, from the U.S. Geological Survey streamflow gage at Kenneth Road to 63rd Street, of Indian Creek from the Kansas-Missouri border to its mouth, and of Dyke Branch from the Kansas-Missouri border to its mouth, to determine the estimated extent of flood inundation at selected flood stages on the Blue River, Indian Creek, and Dyke Branch. The results of this study spatially interpolate information provided by U.S. Geological Survey gages, Kansas City Automated Local Evaluation in Real Time gages, and the National Weather Service flood-peak prediction service that comprise the Blue River flood-alert system and are a valuable tool for public officials and residents to minimize flood deaths and damage in Kansas City. To provide public access to the information presented in this report, a World Wide Web site (http://mo.water.usgs.gov/indep/kelly/blueriver) was created that displays the results of two-dimensional modeling between Hickman Mills Drive and 63rd Street, estimated flood-inundation maps for 13 flood stages, the latest gage heights, and National Weather Service stage forecasts for each forecast location within the study area. The results of a previous study of flood inundation on the Blue River from 63rd Street to the mouth also are available. In addition the full text of this report, all tables and maps are available for download (http://pubs.usgs.gov/sir/2008/5068). Thirteen flood-inundation maps were produced at 2-foot intervals for water-surface elevations from 763.8 to 787.8 feet referenced to the Blue River at the 63rd Street Automated Local Evaluation in Real Time stream gage operated by the city of Kansas City, Missouri. Each map is associated with gages at Kenneth Road, Blue Ridge Boulevard, Kansas City (at Bannister Road), U.S. Highway 71

Malaria surveillance among the displaced Karen population in Thailand April 1984 to February 1989, Mae Sot, Thailand.

PubMed

Decludt, B; Pecoul, B; Biberson, P; Lang, R; Imivithaya, S

1991-12-01

Right from the arrival of the displaced Karen people in Thailand, Médecins sans Frontières (MSF) identified malaria as the top priority problem. A program of patient care based on the coupled laboratory/dispensary was set up in April 1984. Immediately a system of surveillance of morbidity and mortality from malaria was set up. This study consisted of analysing data gathered over a period of five years. During this time, the displaced population increased from 9,000 to 20,000. Analysis of the trends shows a hyperendemic situation with an annual incidence rate of 1,067 per thousand in 1984. This figure was 600 per thousand in 1988. 1,500 blood smears were checked each month and the positive predictive value of clinical suspicion was 45% on average. Plasmodium falciparum represented 80% of infections. The malaria case fatality ratio over the course of the last two years of surveillance was 0.3%. Five years observation show that the fight against malaria in this region can be based on the development of curative services and laboratories.

Relating Seismicity to Dike Emplacement, and the Conundrum of Dyke-Parallel Faulting

NASA Astrophysics Data System (ADS)

Dering, G.; Micklethwaite, S.; Cruden, A. R.; Barnes, S. J.; Fiorentini, M. L.

2016-12-01

Seismic monitoring shows that faulting and fracturing precede and accompany magma emplacement on timescales of hours and days. One outstanding problem is that the precision of earthquake hypocentre locations is typically limited to tens or hundreds of meters and cannot resolve whether the hypocentres relate to strain of wall rock fragments within the dikes, in a process zone around the intrusion or peripherally in the country rock. We examine a swarm of 19 dolerite dikes, near Albany, Western Australia using an unmanned aerial vehicle and Structure-from-Motion photogrammetry to obtain accurate, high resolution 3D reconstructions of outcrop and to digitally extract structural data. We find rare overprinting relationships indicate dike emplacement and faulting was coeval and that the number of faults/fractures increase into the dike swarm (2.2 ± 0.7 more fractures, per unit length in host rocks intruded by dikes relative to the background value). The faults are cataclasite-bearing and parallel to the dikes but intriguingly dike emplacement appears to have been accommodated by mode 1 extension. We further provide the first evidence that dike-parallel shear failure occurs in a damage zone associated with the dike swarm. These results support seismological observations of dike-parallel shear failure associated with some intrusion events, which contradict Mohr-Coulomb theory and numerical modelling of dike propagation in brittle-elastic rock, where shear failure is predicted to occur on faults oriented approximately 30° to the dyke plane. We suggest the dike swarm occupies a network of joints and fractures formed prior to swarm emplacement but then reactivated ahead of propagating dikes and remaining active during the early stages of emplacement.

A system that 'walks the talk'. Using improved community health status for CEO evaluation and compensation. Interview by Karen Gardner.

PubMed

McMeekin, J C; Billings, R W

1994-04-01

Crozer-Keystone Health System, with corporate headquarters in Media, PA, is relatively new. The system was formed in 1990 to integrate four hospitals--roughly 1,160 acute care beds--five long-term care facilities, skilled nursing facilities and personal care facilities. According to President and CEO John C. McMeekin, the system comprises "very aggressive" programs in senior wellness, geriatric care, women's and children's health, behavioral medicine and psychiatric substance abuse. And it also has a large managed care organization that was undertaken as part of a joint venture with members of the hospitals' medical staff. The system is still defining itself, and perhaps that's why it has been willing to venture into an area that is virtually unique among health care organizations: using community health status indicators as part of the CEO's annual evaluation and compensation. Recently, Trustee editor Karen Gardner spoke to McMeekin and board Chairman Richard W. Billings about a major community needs assessment project that the system undertook in 1991 and how it is using the results of that study.

The influence of heterogeneity on coastal groundwater flow - physical and numerical modeling of fringing reefs, dykes and structured conductivity fields

NASA Astrophysics Data System (ADS)

Houben, Georg J.; Stoeckl, Leonard; Mariner, Katrina E.; Choudhury, Anis S.

2018-03-01

Geological heterogeneity of the subsurface, caused by both discrete features and spatially distributed hydraulic conductivity fields, affects the flow of coastal groundwater. It influences the shape and the position of the interface between saltwater and freshwater, as well as the location and flux rate of freshwater discharge to the ocean. Fringing reefs lead to a bimodal regime of freshwater discharge, with discharge at the beach face and through deeper, submarine springs. Impermeable vertical flow barriers (dykes) lead to an impoundment of fresh groundwater and a compartmentalization of the aquifer but also to a delayed expulsion of saline water. Spatially distributed conductivity fields affect the shape of the interface and the geometry of the saltwater wedge. Higher effective conductivities lead to a further landward intrusion of the wedge toe. These flow characteristics can be important for groundwater extraction, the delineation of protection zones and the assessment of contaminant transport to coastal ecosystems.

Rationale and design of the Karolinska-Rennes (KaRen) prospective study of dyssynchrony in heart failure with preserved ejection fraction.

PubMed

Donal, Erwan; Lund, Lars H; Linde, Cecilia; Edner, Magnus; Lafitte, Stéphane; Persson, Hans; Bauer, Fabrice; Ohrvik, John; Ennezat, Pierre-Vladimir; Hage, Camilla; Löfman, Ida; Juilliere, Yves; Logeart, Damien; Derumeaux, Geneviève; Gueret, Pascal; Daubert, Jean-Claude

2009-02-01

Heart failure with preserved ejection fraction (HFPEF) is common but not well understood. Electrical dyssynchrony in systolic heart failure is harmful. Little is known about the prevalence and the prognostic impact of dyssynchrony in HFPEF. We have designed a prospective, multicenter, international, observational study to characterize HFPEF and to determine whether electrical or mechanical dyssynchrony affects prognosis. Patients presenting with acute heart failure (HF) will be screened so as to identify 400 patients with HFPEF. Inclusion criteria will be: acute presentation with Framingham criteria for HF, left ventricular ejection fraction>or=45%, brain natriuretic peptide (BNP)>100 pg/mL or NT-proBNP>300 pg/mL. Once stabilized, 4-8 weeks after the index presentation, patients will return and undergo questionnaires, serology, ECG, and Doppler echocardiography. Thereafter, patients will be followed for mortality and HF hospitalization every 6 months for at least 18 months. Sub-studies will focus on echocardiographic changes from the acute presentation to the stable condition and on exercise echocardiography, cardiopulmonary exercise testing, and serological markers. KaRen aims to characterize electrical and mechanical dyssynchrony and to assess its prognostic impact in HFPEF. The results might improve our understanding of HFPEF and generate answers to the question whether dyssynchrony could be a target for therapy in HFPEF.

The role of dyking and fault control in the rapid onset of eruption at Chaitén Volcano, Chile

USGS Publications Warehouse

Wicks, Charles; De La, Llera; Lara, L.E.; Lowenstern, J.

2011-01-01

Rhyolite is the most viscous of liquid magmas, so it was surprising that on 2 May 2008 at Chaitén Volcano, located in Chile’s southern Andean volcanic zone, rhyolitic magma migrated from more than 5 km depth in less than 4 hours and erupted explosively with only two days of detected precursory seismic activity. The last major rhyolite eruption before that at Chaitén was the largest volcanic eruption in the twentieth century, at Novarupta volcano, Alaska, in 1912. Because of the historically rare and explosive nature of rhyolite eruptions and because of the surprisingly short warning before the eruption of the Chaitén volcano, any information about the workings of the magmatic system at Chaitén, and rhyolitic systems in general, is important from both the scientific and hazard perspectives. Here we present surface deformation data related to the Chaitén eruption based on radar interferometry observations from the Japan Aerospace Exploration Agency (JAXA) DAICHI (ALOS) satellite. The data on this explosive rhyolite eruption indicate that the rapid ascent of rhyolite occurred through dyking and that melt segregation and magma storage were controlled by existing faults.

The role of dyking and fault control in the rapid onset of eruption at Chaitén volcano, Chile.

PubMed

Wicks, Charles; de la Llera, Juan Carlos; Lara, Luis E; Lowenstern, Jacob

2011-10-19

Rhyolite is the most viscous of liquid magmas, so it was surprising that on 2 May 2008 at Chaitén Volcano, located in Chile's southern Andean volcanic zone, rhyolitic magma migrated from more than 5 km depth in less than 4 hours (ref. 1) and erupted explosively with only two days of detected precursory seismic activity. The last major rhyolite eruption before that at Chaitén was the largest volcanic eruption in the twentieth century, at Novarupta volcano, Alaska, in 1912. Because of the historically rare and explosive nature of rhyolite eruptions and because of the surprisingly short warning before the eruption of the Chaitén volcano, any information about the workings of the magmatic system at Chaitén, and rhyolitic systems in general, is important from both the scientific and hazard perspectives. Here we present surface deformation data related to the Chaitén eruption based on radar interferometry observations from the Japan Aerospace Exploration Agency (JAXA) DAICHI (ALOS) satellite. The data on this explosive rhyolite eruption indicate that the rapid ascent of rhyolite occurred through dyking and that melt segregation and magma storage were controlled by existing faults.

Oral Cancer - Multiple Languages

MedlinePlus

... a new window. Burmese (myanma bhasa) Expand Section Betel Nut - English PDF Betel Nut - myanma bhasa (Burmese) PDF Orange County North ... California Dental Association Karen (S’gaw Karen) Expand Section Betel Nut - English PDF Betel Nut - S’gaw Karen (Karen) ...

Geochemistry and tectonic setting of a lamproite dyke in Kvaløya, North Norway

NASA Astrophysics Data System (ADS)

Kullerud, Kåre; Zozulya, Dmitry; Bergh, Steffen G.; Hansen, Harald; Ravna, Erling J. K.

2011-10-01

A new lamproite occurrence of inferred Carboniferous age intruded into an extensive, more than 5 km long rectilinear fracture zone in a granite of the West Troms Basement Complex, North Norway. This 30 cm wide dyke, which shows well developed chilled margins, is characterized by up to 3 mm long phenocrysts of phlogopite in a fine-grained gray matrix of K-feldspar and K-magnesioarfvedsonite with minor amounts of apatite, Ba-titanates (baotite) and rutile. Based on its mineralogy, whole rock chemistry (e.g., SiO 2 = 54.4-57.3 wt.%, K/Na = 2.02-7.03, K/Al = 0.86-1.22, Mg# = 76-84 and K agp = 1.0-1.7), and specific mineral compositions (e.g. tetrahedral coordination of Fe 3+ in phlogopite, high Fe, but negligible Na in K-feldspar, and high Ti in K-magnesioarfvedsonite and phlogopite) the rock can be classified as a high-Si phlogopite lamproite. Concentrations and element ratios of a number of trace elements (e.g. high LILE and HFSE, except of Nb and Ta, high La/Yb n and low Th/Nb) in addition to isotope data (moderately radiogenic 87Sr/ 86Sr and extremely non-radiogenic 143Nd/ 144Nd; ɛNd(T) varies from - 19.9 to - 22.4) indicate an anorogenic, i. e., within-plate setting for the Kvaløya lamproite, similar to the anorogenic types of lamproite from Leucite Hills (Wyoming) and Smoky Butte (Montana). The Kvaløya lamproite shows high Nb/Ta and simultaneous high Zr, suggesting a multistage enrichment history of its mantle source. It is suggested that in addition to an ancient stage of enrichment (2.1-2.3 Ga, based on Nd model ages), parts of the mantle enrichment possibly resulted from the involvement of subducted materials during metasomatism of the mantle during the Caledonian Orogeny.

Cumulates, Dykes and Pressure Solution in the Ice-Salt Mantle of Europa: Geological Consequences of Pressure Dependent Liquid Compositions and Volume Changes During Ice-Salt Melting Reactions.

NASA Astrophysics Data System (ADS)

Day, S.; Asphaug, E.; Bruesch, L.

2002-12-01

Water-salt analogue experiments used to investigate cumulate processes in silicate magmas, along with observations of sea ice and ice shelf behaviour, indicate that crystal-melt separation in water-salt systems is a rapid and efficient process even on scales of millimetres and minutes. Squeezing-out of residual melts by matrix compaction is also predicted to be rapid on geological timescales. We predict that the ice-salt mantle of Europa is likely to be strongly stratified, with a layered structure predictable from density and phase relationships between ice polymorphs, aqueous saline solutions and crystalline salts such as hydrated magnesium sulphates (determined experimentally by, inter alia, Hogenboom et al). A surface layer of water ice flotation cumulate will be separated from denser salt cumulates by a cotectic horizon. This cotectic horizon will be both the site of subsequent lowest-temperature melting and a level of neutral buoyancy for the saline melts produced. Initial melting will be in a narrow depth range owing to increasing melting temperature with decreasing pressure: the phase relations argue against direct melt-though to the surface unless vesiculation occurs. Overpressuring of dense melts due to volume expansion on cotectic melting is predicted to lead to lateral dyke emplacement and extension above the dyke tips. Once the liquid leaves the cotectic, melting of water ice will involve negative volume change. Impact-generated melts will drain downwards through the fractured zones beneath crater floors. A feature in the complex crater Mannan'an, with elliptical ring fractures around a conical depression with a central pit, bears a close resemblance to Icelandic glacier collapse cauldrons produced by subglacial eruptions. Other structures resembling Icelandic cauldrons occur along Europan banded structures, while resurgence of ice rubble within collapse structures may produce certain types of chaos region. More general contraction of the ice mantle

Contemporary perspectives on psychosomatics in Germany: A commentary on Karen Gubb's paper, "Psychosomatics today: a review of contemporary theory and practice".

PubMed

Frommer, Jörg

2013-02-01

Karen Gubb's (2013) review focuses on contemporary developments in psychoanalytic theory and practice in relation to psychosomatics, starting with some historical remarks, and Paris School with the Attachment approach. This paper examines the question of how the German scene fits into the issues raised in Gubb's discussion. From a historical point of view, psychosomatic thinking had already come into existence at the beginning of the twentieth century in internal medicine, influenced not only by Freud's ideas, but also by holistic philosophical approaches, anthropology, and semiotic systems theory as well. Psychosomatics is still under the influence of psychodynamic thinking, but as a required subject for all medical students, it is currently more involved in inpatient treatment settings than in psychoanalyses in the classical couch setting. Research projects using standardized questionnaires, neuroimaging, and other empirical methods have also proved that these treatments are as effective as therapy based on psychoanalytic concepts like alexithymia or the Attachment approach. In addition, qualitative methods have been implemented to grasp the fine-grained conscious and unconscious processes in the inner life of patients and in the verbal and nonverbal interaction phenomena of therapies. To sum up: Recent developments in psychoanalytic theory, which begin to overcome the differences among psychoanalytic schools in favor of re-erecting a common psychoanalytic understanding like that demonstrated in Gubb's article, fit together in bridging the gap between insights from classical psychoanalyses and results from empirical research.

Community engagement and the social context of targeted malaria treatment: a qualitative study in Kayin (Karen) State, Myanmar.

PubMed

Sahan, Kate; Pell, Christopher; Smithuis, Frank; Phyo, Aung Kyaw; Maung, Sai Maung; Indrasuta, Chanida; Dondorp, Arjen M; White, Nicholas J; Day, Nicholas P J; von Seidlein, Lorenz; Cheah, Phaik Yeong

2017-02-14

The spread of artemisinin-resistance in Plasmodium falciparum is a threat to current global malaria control initiatives. Targeted malaria treatment (TMT), which combines mass anti-malarial administration with conventional malaria prevention and control measures, has been proposed as a strategy to tackle this problem. The effectiveness of TMT depends on high levels of population coverage and is influenced by accompanying community engagement activities and the local social context. The article explores how these factors influenced attitudes and behaviours towards TMT in Kayin (Karen) State, Myanmar. Semi-structured interviews were conducted with villagers from study villages (N = 31) and TMT project staff (N = 14) between March and July 2015. Community engagement consisted of a range of activities to communicate the local malaria situation (including anti-malarial drug resistance and asymptomatic malaria), the aims of the TMT project, and its potential benefits. Community engagement was seen by staff as integral to the TMT project as a whole and not a sub-set of activities. Attitudes towards TMT (including towards community engagement) showed that developing trusting relationships helped foster participation. After initial wariness, staff received hospitality and acceptance among villagers. Offering healthcare alongside TMT proved mutually beneficial for the study and villagers. A handful of more socially-mobile and wealthy community members were reluctant to participate. The challenges of community engagement included time constraints and the isolation of the community with its limited infrastructure and a history of conflict. Community engagement had to be responsive to the local community even though staff faced time constraints. Understanding the social context of engagement helped TMT to foster respectful and trusting relationships. The complex relationship between the local context and community engagement complicated evaluation of the community strategy

Geochemistry and geochronology of the ∼0.82 Ga high-Mg gabbroic dykes from the Quanji Massif, southeast Tarim Block, NW China: Implications for the Rodinia supercontinent assembly

NASA Astrophysics Data System (ADS)

Liao, Fanxi; Wang, Qinyan; Chen, Nengsong; Santosh, M.; Xu, Yixian; Mustafa, Hassan Abdelsalam

2018-05-01

The role of the Tarim Block in the reconstruction of the Neoproterozoic supercontinent Rodinia remains contentious. Here we report a suite of high-Mg gabbroic dykes from the Yingfeng area in northwestern Quanji Massif, which is considered as a fragment of the Tarim Block in NW China. Magmatic zircons from these dykes yield to have a weighted mean 206Pb/238U age of 822.2 ± 5.3 Ma, recording the timing of their emplacement. The gabbros have high MgO (9.91-13.09 wt%), Mg numbers (69.89-75.73) and CaO (8.41-13.55 wt%), medium FeOt (8.50-9.67 wt%) and TiO2 (0.67-0.93 wt%), variable Al2O3 (13.04-16.07 wt%), and high Cr (346.14-675.25 ppm), but relatively low Ni (138.72-212.94 ppm), suggestive of derivation from a primary magma. The rocks display chondrite-normalized LREE patterns with weak fractionation but flat HREE patterns relative to those of the N-MORB. Their primitive mantle normalized trace elemental patterns show positive Rb, Ba and U but negative Th, Nb, Ti and Zr anomalies, carrying characteristics of both mid-ocean ridge basalts and arc basalts. The εHf(t) values of the zircons from these rocks vary from +4.7 to +13.5 with depleted mantle model ages (TDM) of 1.23-0.85 Ga, and the youngest value nearly approaching that for the coeval depleted mantle, suggesting significant addition of juvenile materials. Our data suggest that the strongly depleted basaltic magma was probably sourced from a depleted mantle source that had undergone metasomatism by subduction-related components in a back-arc setting. Accordingly we postulate that a subduction-related tectonic regime possibly prevailed at ∼0.8 Ga along the southeastern margin of the Tarim Block. Combining with available information from the northern Tarim Block, we propose an opposite verging double-sided subduction model for coeval subduction of the oceanic crust beneath both the southern and northern margins of the Tarim Block during early Neoproterozoic.

Subglacial volcanic activity above a lateral dyke path during the 2014-2015 Bárdarbunga-Holuhraun rifting episode, Iceland

NASA Astrophysics Data System (ADS)

Reynolds, Hannah I.; Gudmundsson, Magnús T.; Högnadóttir, Thórdís; Magnússon, Eyjólfur; Pálsson, Finnur

2017-06-01

The rifting episode associated with the Bárdarbunga-Holuhraun eruption in 2014-2015 included the first observations of major dyke propagation under ice. Three shallow ice depressions (ice cauldrons) with volumes ranging from 1 to 18 million m3 formed in Dyngjujökull glacier above the 48-km-long lateral path of the magma, at 4, 7 and 12 km from the northern glacier edge. Aircraft-based radar altimetry profiling was used to map the evolution of the cauldrons and construct a time series of the heat transfer rates. Out of the three scenarios explored: (1) onset or increase of hydrothermal activity, (2) convection within vertical fissures filled with water overlying intruded magma and (3) subglacial eruptions, the last option emerges as the only plausible mechanism to explain the rapid heat transfer observed in a location far from known geothermal areas. The thermal signals at two of the cauldrons are consistent with effusive subglacial eruptions. The formation of the northernmost cauldron was more rapid, indicating faster heat transfer rates. Radio-echo sounding data indicate that in contrast to the other two cauldrons, an intrusion of eruptive products occurred into the glacier, reaching 50-60 m above bedrock with the increased magma-ice contact explaining the more rapid heat transfer. We propose that the 2-m widening associated with graben formation increased the groundwater storage capacity of the bedrock, creating space for the meltwater to be stored, explaining the absence of meltwater pulses draining from Dyngjujökull.

Mafic dykes intrusive into Pre-Cambrian rocks of the São Luís cratonic fragment and Gurupi Belt (Parnaíba Province), north-northeastern Brazil: Geochemistry, Sr-Nd-Pb-O isotopes, 40Ar/39Ar geochronology, and relationships to CAMP magmatism

NASA Astrophysics Data System (ADS)

Klein, Evandro L.; Angélica, Rômulo S.; Harris, Chris; Jourdan, Fred; Babinski, Marly

2013-07-01

Dykes of diabase and microgabbro intruded into Pre-Cambrian rocks of the São Luís cratonic fragment and Gurupi Belt, which are tectonic and erosive windows of the Parnaíba Basin in north-northeastern Brazil. Ar-Ar ages were determined, and major, trace element, and Nd-Sr-Pb-O isotopic compositions of these dykes were measured to provide insights into their age, and into the nature of their mantle sources and petrogenetic processes. The data have also been used to compare the chemical and isotopic signatures of the dykes with those of the Central Atlantic Magmatic Province (CAMP). Four chemical groups of mafic dykes have been identified. These comprise two subtypes of high-Ti rocks (i) HTi-1 (TiO2 < 2.3 wt.%; SiO2 > 47 wt.%), (ii) HTi-2 (TiO2 > 2.7 wt.%; SiO2 > 47 wt.%), in addition to (iii) evolved high-Ti (TiO2 > 4 wt.%; SiO2 of ~ 46 wt.%) and (iv) low-Si (TiO2 > 2.2 wt.%; SiO2 < 45 wt.%) rocks. 40Ar/39Ar geochronology of plagioclase returned ages of 201 ± 4 Ma and 193 ± 10 Ma for the HTi-2 subtype, and of 201 ± 2 Ma and 207 ± 9 Ma for the evolved high-Ti group. The HTi-1 and low-Si groups presented highly disturbed age spectra, and did not allow the definition of their emplacement ages. The Argon data indicate an age > 200 Ma for the low-Si group and are dubious with respect to the age of theHTi-1 subtype, if coeval with (i.e., ~ 200 Ma), or older than, the HTi-2 and evolved high-Ti types. All groups present δ18O values of pyroxene that are compatible with uncontaminated mantle-derived magmas. The HTi-1 subtype (average 143Nd/144Nd200 = 0.512644; 87Sr/86Sr200 = 0.7035; 206Pb/204Pb of 17.86) shows the less enriched and less fractionated (more primitive) trace element distribution of all groups. The HTi-2 subtype shows enriched trace element pattern and depleted Nd-Sr signature (143Nd/144Nd200 = 0.512610; 87Sr/86Sr200 = 0.7037) and average 206Pb/204Pb ratios of 17.23. The evolved high-Ti chemical group shows average ratios of 143Nd/144Nd200 = 0.512558, 87Sr

The prognostic significance of atrial fibrillation in heart failure with preserved ejection function: insights from KaRen, a prospective and multicenter study.

PubMed

Bosseau, Christian; Donal, Erwan; Lund, Lars H; Oger, Emmanuel; Hage, Camilla; Mulak, Geneviève; Daubert, Jean-Claude; Linde, Cecilia

2017-06-01

The prognostic value of atrial fibrillation (AF) in heart failure with preserved ejection fraction (HFPEF) remains controversial. We sought to study the prognostic value of AF in a prospective cohort and to characterize the HFPEF patients with AF. KaRen was a prospective, multicenter, international, observational study intended to characterize HFPEF; 538 patients presenting with an acute decompensated cardiac failure and a left ventricular EF > 45% were included. EKG and echocardiogram performed 4-8 week following the index hospitalization were analyzed in core centers. Clinical and echocardiographic characteristics of patients in sinus rhythm vs. with documented AF at enrolment (decompensated HF), upon their 4-8-week visit (in presumed stable clinical condition) and according to patients' cardiac history, were compared. The primary study endpoint was death from any cause or first hospitalization for decompensated heart failure (HF). A total of 413 patients (32% in AF) were analyzed, with a mean follow-up period of 28 months. The patients were primarily elderly individuals (mean age: 76.2 years), with a slight female predominance and a high prevalence of non-cardiovascular comorbidities. The baseline echocardiographic characteristics and the natriuretic peptide levels were indicative of a more severe heart condition among the patients with AF. However, the patients with AF exhibited a similar survival-free interval compared with the patients in sinus rhythm. In this elderly HFPEF population with a high prevalence of non-cardiovascular comorbidities, the presence of AF was not associated with a worse prognosis despite impaired clinical and echocardiographic features.ClinicalTrials.gov: NCT00774709.

Regularities of spatial association of major endogenous uranium deposits and kimberlitic dykes in the uranium ore regions of the Ukrainian Shield

NASA Astrophysics Data System (ADS)

Kalashnyk, Anna

2015-04-01

During exploration works we discovered the spatial association and proximity time formation of kimberlite dykes (ages are 1,815 and 1,900 Ga for phlogopite) and major industrial uranium deposits in carbonate-sodium metasomatites (age of the main uranium ore of an albititic formation is 1,85-1,70 Ga according to U-Pb method) in Kirovogradsky, Krivorozhsky and Alekseevsko-Lysogorskiy uranium ore regions of the Ukrainian Shield (UkrSh) [1]. In kimberlites of Kirovogradsky ore region uranium content reaches 18-20 g/t. Carbon dioxide is a major component in the formation of hydrothermal uranium deposits and the formation of the sodium in the process of generating the spectrum of alkaline ultrabasic magmas in the range from picritic to kimberlite and this is the connection between these disparate geochemical processes. For industrial uranium deposits in carbonate-sodium metasomatitics of the Kirovogradsky and Krivorozhsky uranium ore regions are characteristic of uranyl carbonate introduction of uranium, which causes correlation between CO2 content and U in range of "poor - ordinary - rich" uranium ore. In productive areas of uranium-ore fields of the Kirovogradsky ore region for phlogopite-carbonate veinlets of uranium ore albitites deep δ13C values (from -7.9 to -6.9o/oo) are characteristic. Isotope-geochemical investigation of albitites from Novokonstantynovskoe, Dokuchaevskoe, Partyzanskoe uranium deposits allowed obtaining direct evidence of the involvement of mantle material during formation of uranium albitites in Kirovogradsky ore region [2]. Petrological characteristics of kimberlites from uranium ore regions of the UkrSh (presence of nodules of dunite and harzburgite garnet in kimberlites, diamonds of peridotite paragenesis, chemical composition of indicator minerals of kimberlite, in particular Gruzskoy areas pyropes (Cr2O3 = 6,1-7,1%, MgO = 19,33-20,01%, CaO = 4,14-4,38 %, the content of knorringite component of most grains > 50mol%), chromites (Cr2O3 = 45

Petrology and metamorphic evolution of ultramafic rocks and dolerite dykes of the Betic Ophiolitic Association (Mulhacén Complex, SE Spain): evidence of eo-Alpine subduction following an ocean-floor metasomatic process

NASA Astrophysics Data System (ADS)

Puga, E.; Nieto, J. M.; Díaz de Federico, A.; Bodinier, J. L.; Morten, L.

1999-10-01

The Betic Ophiolitic Association, cropping out within the Mulhacén Complex (Betic Cordilleras), is made up of numerous metre- to kilometre-sized lenses of mafic and/or ultramafic and meta-sedimentary rocks. Pre-Alpine oceanic metasomatism and metamorphism caused the first stage of serpentinization in the ultramafic sequence of this association, which is characterized by local clinopyroxene (Cpx) breakdown and Ca-depletion, and complementary rodingitization of the basic dykes intruded in them. Subsequent eo-Alpine orogenic metamorphism developed eclogite facies assemblages in ultramafic and basic lithotypes, which were partly retrograded in Ab-Ep-amphibolite facies conditions during a meso-Alpine event. The heterogeneous development of the oceanic metasomatism in the ultramafic rock-types led to the patchy development of highly serpentinized Ca-depleted domains, without gradual transition to the host, and less serpentinized, Cpx-bearing ultramafites, mainly lherzolitic in composition. The high-pressure eo-Alpine recrystallization of these ultramafites in subduction conditions originated secondary harzburgites in the Ca-depleted domains, consisting of a spinifex-like textured olivine+orthopyroxene paragenesis, and a diopside+Ti-clinohumite paragenesis in the enclosing lherzolitic rocks. During the meso-Alpine event, secondary harzburgites were partly transformed into talc+antigorite serpentinites, whereas the diopside and clinohumite-bearing residual meta-lherzolites were mainly transformed into Cpx-bearing serpentinites. Relics of mantle-derived colourless olivine may be present in the more or less serpentinized secondary harzburgites. These relics are overgrown by the eo-Alpine brown pseudo-spinifex olivine, which contains submicroscopic inclusions of chromite, ilmenite and occasional halite and sylvite, inherited from its parental oceanic serpentine. The same type of mantle-derived olivine relics is also preserved within the Cpx-bearing serpentinites, although it

Using Different Grazing Practices for Increasing Plant Biodiversity in the Dykes and Embankments Along the Rhône River (Southern France)

NASA Astrophysics Data System (ADS)

Moinardeau, Cannelle; Mesléard, François; Dutoit, Thierry

2016-12-01

Extensive grazing by domestic herbivores is a widespread management practice used since the 80s in many European agro-ecosystems such as semi-natural grasslands to maintain open habitats and to enhance biodiversity. Such grazing systems have principally been tested in cultural ecosystems of high nature value threatened by grazing abandonment. However, there have been few case studies of grazing management in very anthropized ecosystems, such as the new ecosystems created by urban or industrial conversions. In Southern France, the Rhône channeling for navigation and electricity production generated in the 1950s the construction of thousands of hectares of dams and dykes which were colonized naturally by diverse plant communities. Yet shrub encroachment and the consequent recourse to mechanical cutting to facilitate control and maintenance, raise the question of how best to maintain and manage these new habitats. Consequently, since 1999, different low-intensity grazing management systems using rustic breeds of cattle, horses and goats have been tested on a protected reserve of 1454 ha located in the lower part of the Rhône river. Extensive grazing, more than cutting or no management, positively modified vegetation heterogeneity (beta-diversity), the target open grassland species, but not plant species richness (alpha-diversity). However, the current monitoring shows that these benefits of grazing will be confirmed only if low-intensity grazing systems are sustained and if new adaptations can be also made, such as the use of mixed stocking and the establishment of multiyear contracts with breeders.

Using Different Grazing Practices for Increasing Plant Biodiversity in the Dykes and Embankments Along the Rhône River (Southern France).

PubMed

Moinardeau, Cannelle; Mesléard, François; Dutoit, Thierry

2016-12-01

Extensive grazing by domestic herbivores is a widespread management practice used since the 80s in many European agro-ecosystems such as semi-natural grasslands to maintain open habitats and to enhance biodiversity. Such grazing systems have principally been tested in cultural ecosystems of high nature value threatened by grazing abandonment. However, there have been few case studies of grazing management in very anthropized ecosystems, such as the new ecosystems created by urban or industrial conversions. In Southern France, the Rhône channeling for navigation and electricity production generated in the 1950s the construction of thousands of hectares of dams and dykes which were colonized naturally by diverse plant communities. Yet shrub encroachment and the consequent recourse to mechanical cutting to facilitate control and maintenance, raise the question of how best to maintain and manage these new habitats. Consequently, since 1999, different low-intensity grazing management systems using rustic breeds of cattle, horses and goats have been tested on a protected reserve of 1454 ha located in the lower part of the Rhône river. Extensive grazing, more than cutting or no management, positively modified vegetation heterogeneity (beta-diversity), the target open grassland species, but not plant species richness (alpha-diversity). However, the current monitoring shows that these benefits of grazing will be confirmed only if low-intensity grazing systems are sustained and if new adaptations can be also made, such as the use of mixed stocking and the establishment of multiyear contracts with breeders.

Interpretation of Source Parameters from Total Gradient of Gravity and Magnetic Anomalies Caused by Thin Dyke using Nonlinear Global Optimization Technique

NASA Astrophysics Data System (ADS)

Biswas, A.

2016-12-01

A proficient way to deal with appraisal model parameters from total gradient of gravity and magnetic data in light of Very Fast Simulated Annealing (VFSA) has been exhibited. This is the first run through of applying VFSA in deciphering total gradient of potential field information with another detailing estimation brought on because of detached causative sources installed in the subsurface. The model parameters translated here are the amplitude coefficient (k), accurate origin of causative source (x0) depth (z0) and the shape factor (q). The outcome of VFSA improvement demonstrates that it can exceptionally decide all the model parameters when shape variable is fixed. The model parameters assessed by the present strategy, for the most part the shape and depth of the covered structures was observed to be in astounding concurrence with the genuine parameters. The technique has likewise the capability of dodging very uproarious information focuses and enhances the understanding results. Investigation of Histogram and cross-plot examination likewise proposes the translation inside the assessed ambiguity. Inversion of noise-free and noisy synthetic data information for single structures and field information shows the viability of the methodology. The procedure has been carefully and adequately connected to genuine field cases (Leona Anomaly, Senegal for gravity and Pima copper deposit, USA for magnetic) with the nearness of mineral bodies. The present technique can be to a great degree material for mineral investigation or ore bodies of dyke-like structure rooted in the shallow and more deep subsurface. The calculation time for the entire procedure is short.

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78 FR 2892 - Privacy Act, Exempt Record System; Withdrawal

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-15

..., August 28, 2012, is withdrawn effective January 10, 2013. FOR FURTHER INFORMATION CONTACT: Karen Pla, the NIH Privacy Act Officer, by email at KarenPla@nih.gov or by telephone on 301-402-6201; and/or Jerry...

Intra-cone plumbing system and eruptive dynamics of small-volume basaltic volcanoes: A case study in the Calatrava Volcanic Field

NASA Astrophysics Data System (ADS)

Carracedo-Sánchez, M.; Sarrionandia, F.; Ábalos, B.; Errandonea-Martin, J.; Gil Ibarguchi, J. I.

2017-12-01

The Manoteras volcano (Tortonian to Pleistocene, Calatrava Volcanic Field, Spain) is composed of a scoria and spatter cone surrounded by a field of pahoehoe lava. The volcanic cone is made essentially of vitreous lapilli-tuffs with intercalations of vitreous tuffs and spatter deposits, without any intercalations of lava flows. Erosion has uncovered an intra-cone plumbing system formed by coherent dykes and pyroclastic dykes (mixed-type dykes). This dyke swarm reflects processes of intrusion at the end of the eruption or even post-eruption. All the volcanic products are nephelinitic in composition. The main dyke is up to 3.4 m thick and has an exposed length of 1000 m. It is composed mostly of coherent nephelinite with some pyroclastic sections at its northern extremity. This dyke is regarded as a feeder dyke of the volcano, although the upper parts of the dike have been eroded, which prevents the observation of the characteristics and nature of the possible overlying vent(s). Mixed-type dykes could also have acted as small linear vents and indicate that the magma fragmentation level during final waning stages of the eruption was located inside the volcanic cone. The pyroclastic deposits that make up the volcanic cone at the current exposure level were probably developed during a major phase of violent Strombolian style that formed the scoria cone, followed by a Hawaiian phase that formed the summital intracrater spatter deposit. Three central-type vents have been identified: one at the highest point of the remnant volcanic cone (summital vent), from where the earlier explosive eruptions took place, and the other two at the fringe of the cone base, from where emissions were only effusive. The lava flows were emitted from these boccas through the scoria cone feeding the lava field. The results obtained, based on careful field observations, add substantial complexity to the proposed eruptive models for small-volume basaltic volcanoes as it appears evident that there

Tetanus, Diphtheria, and Pertussis Vaccines - Multiple Languages

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Communication between earthquake clusters separated by over 30 km supports simple volcano plumbing

NASA Astrophysics Data System (ADS)

Jonsdottir, K.; Jonasson, K.; Gudmundsson, M. T.; Hensch, M.; Hooper, A. J.; Holohan, E. P.; Sigmundsson, F.; Halldorsson, S. A.; Hognadottir, T.; Magnússon, E.; Pálsson, F.; Walter, T. R.; Ofeigsson, B.; Parks, M.; Roberts, M. J.; Hjorleifsdottir, V.; Cesca, S.; Guðmundsson, G.; Hreinsdottir, S.; Jarosch, A. H.; Dumont, S.; Fridriksdóttir, H. M.; Barsotti, S.; Einarsson, P.

2015-12-01

The subglacial Bárðarbunga volcano is composed of a large oval caldera (7x11 km) and fissures extending tens of kilometers away from the caldera along the rift zone, which marks the divergent plate boundary across Iceland. On August 16th, 2014 an intense seismic swarm started below the Bárðarbunga caldera and in the two weeks that followed a dyke migrated some 47 km laterally in the uppermost 6-10 km of the crust along the rift. The dyke propagation terminated in lava fields just north of Vatnajökull glacier, where a major (1.5 km3) six months long eruption took place. Intense earthquake activity in the caldera started in the period August 21-24 with over 70 M5 earthquakes accompanying slow caldera collapse, as verified by various geodetic measurements. The subsidence is likely due to magma withdrawal from a reservoir at depth beneath the caldera. During a five months period, October-February, the seismic activity was separated by over 30 km in two clusters; one along the caldera rims (due to piecewise caldera subsidence) and the other at the far end of the dyke (as a result of small shear movements). Here we present statistical analysis comparing the temporal behaviour of seismicity recorded in the two clusters. By comparing the earthquake rate in the dyke in temporal bins before and after caldera subsidence earthquakes to the rate away from these bins (background rate), we show that the number of dyke earthquakes was significantly higher (p <0.05) in the period 0-3 hours before a large earthquake (>M4.6) in the caldera. Increased dyke seismicity was also observed 0-3 hours following a large caldera earthquake. Elevated seismicity in the dyke before a large caldera earthquake may occur when a constriction in the dyke was reduced, followed by pressure drop in the chamber. Assuming that the large caldera earthquakes occurred when chamber pressure was lowest, the subsiding caldera piston may have caused temporary higher pressure in the dyke and thereby increased

Earth Observations taken by the Expedition 25 crew

NASA Image and Video Library

2010-09-30

ISS025-E-005538 (30 Sept. 2010) --- The Great Dyke of Zimbabwe, Africa is featured in this image photographed by an Expedition 25 crew member on the International Space Station. The Great Dyke of Zimbabwe is a prominent geological feature that extends for over 550 kilometers, varying from 3-12 kilometers in width across the center of the country northeast – southwest; the southern end of the Dyke is illustrated in this view. The Dyke (or Dike in American English) is a layered mafic intrusion of igneous, metal-bearing rock that has been dated using uranium-lead isotopes to approximately 2.5 billion years in age, according to scientists. It intrudes even older rocks of the African craton, or core of oldest rocks forming the continent; in cross section, the Great Dyke looks somewhat triangular or keel-shaped suggesting to geologists that it rose along deep faults associated with extension of the African crust. Layered mafic intrusions are usually associated with economically important metals such as chromium, nickel, copper, platinum, titanium, iron, vanadium and tin. Chromium, in the form of the mineral chromite and platinum are particularly abundant in the Great Dyke and actively mined. Younger faults have offset sections of the Dyke along its length – two of the most obvious faults in the image are indicated, with arrows showing the relative directions of offset relative to the main trend of the intrusion. While the Great Dyke and its metal ores are products of geologic processes operating in the deep past, more recent events have also left their mark on the landscape as illustrated by two large fire burn scars which are visible at top center.

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Solidification of basaltic magma during flow in a dike.

USGS Publications Warehouse

Delaney, P.T.; Pollard, D.D.

1982-01-01

A model for time-dependent unsteady heat transfer from magma flowing in a dyke is developed. The ratio of solidification T to magma T is the most important parameter. Observations of volcanic fissure eruptions and study of dykes near Ship Rock, New Mexico, show that the low T at dyke margins and the rapidly advancing solidification front predicted by the model are qualitatively correct.-M.S.

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Indigenous systems of forest classification: understanding land use patterns and the role of NTFPs in shifting cultivators' subsistence economies.

PubMed

Delang, Claudio O

2006-04-01

This article discusses the system of classification of forest types used by the Pwo Karen in Thung Yai Naresuan Wildlife Sanctuary in western Thailand and the role of nontimber forest products (NTFPs), focusing on wild food plants, in Karen livelihoods. The article argues that the Pwo Karen have two methods of forest classification, closely related to their swidden farming practices. The first is used for forest land that has been, or can be, swiddened, and classifies forest types according to growth conditions. The second system is used for land that is not suitable for cultivation and looks at soil properties and slope. The article estimates the relative importance of each forest type in what concerns the collection of wild food plants. A total of 134 wild food plant species were recorded in December 2004. They account for some 80-90% of the amount of edible plants consumed by the Pwo Karen, and have a base value of Baht 11,505 per year, comparable to the cash incomes of many households. The article argues that the Pwo Karen reliance on NTFPs has influenced their land-use and forest management practices. However, by restricting the length of the fallow period, the Thai government has caused ecological changes that are challenging the ability of the Karen to remain subsistence oriented. By ignoring shifting cultivators' dependence on such products, the involvement of governments in forest management, especially through restrictions imposed on swidden farming practices, is likely to have a considerable impact on the livelihood strategies of these communities.

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Interview with a quality leader--Karen Davis, executive director of The Commonwealth Fund. Interview by Lecia A. Albright.

PubMed

Davis, Karen

2009-01-01

Karen Davis is president of The Commonwealth Fund, a national philanthropy engaged in independent research on health and social policy issues. Dr. Davis is a nationally recognized economist, with a distinguished career in public policy and research. Before joining the Fund, she served as chairman of the Department of Health Policy and Management at The Johns Hopkins School of Public Health, where she also held an appointment as professor of economics. She served as deputy assistant secretary for health policy in the Department of Health and Human Services from 1977 to 1980, and was the first woman to head a U.S. Public Health Service agency. Before her government career, Ms. Davis was a senior fellow at the Brookings Institution in Washington, DC; a visiting lecturer at Harvard University; and an assistant professor of economics at Rice University. A native of Oklahoma, she received her PhD in economics from Rice University, which recognized her achievements with a Distinguished Alumna Award in 1991. Ms. Davis is the recipient of the 2000 Baxter-Allegiance Foundation Prize for Health Services Research. In the spring of 2001, Ms. Davis received an honorary doctorate in human letters from John Hopkins University. In 2006, she was selected for the Academy Health Distinguished Investigator Award for significant and lasting contributions to the field of health services research in addition to the Picker Award for Excellence in the Advancement of Patient Centered Care. Ms. Davis has published a number of significant books, monographs, and articles on health and social policy issues, including the landmark books HealthCare Cost Containment, Medicare Policy, National Health Insurance: Benefits, Costs, and Consequences, and Health and the War on Poverty. She serves on the Board of Visitors of Columbia University, School of Nursing, and is on the Board of Directors of the Geisinger Health System. She was elected to the Institute of Medicine (IOM) in 1975; has served two

Quartz Crystal Microbalance Studies Of Dimethyl Methylphosphonate Sorption Into Trisilanolphenyl-Poss Films

DTIC Science & Technology

2006-11-06

Transverse shear wave of a quartz crystal with an applied thin film�..�.31 Figure 2.4 Butterworth van - Dyke model for a quartz crystal near...resonance��..�.32 Figure 2.5 Butterworth van - Dyke model for a loaded quartz crystal at resonance...�.34 Figure 2.6 Butterworth van - Dyke model for a...surface chemistry . A thorough understanding of the reaction pathways of CWAs will aid in the development of CWA sensors, environmentally friendly

Beyond Terman: Contemporary Longitudinal Studies of Giftedness and Talent.

ERIC Educational Resources Information Center

Subotnik, Rena F., Ed.; Arnold, Karen D., Ed.

This volume presents 16 papers describing recent longitudinal studies of giftedness. Papers have the following titles and authors: (1) "Longitudinal Study of Giftedness and Talent" (Rena F. Subotnik and Karen D. Arnold); (2) "The Illinois Valedictorian Project: Early Adult Careers of Academically Talented Male High School Students" (Karen D.…

Global cost analysis on adaptation to sea level rise based on RCP/SSP scenarios

NASA Astrophysics Data System (ADS)

Kumano, N.; Tamura, M.; Yotsukuri, M.; Kuwahara, Y.; Yokoki, H.

2017-12-01

Low-lying areas are the most vulnerable to sea level rise (SLR) due to climate change in the future. In order to adapt to SLR, it is necessary to decide whether to retreat from vulnerable areas or to install dykes to protect them from inundation. Therefore, cost- analysis of adaptation using coastal dykes is one of the most essential issues in the context of climate change and its countermeasures. However, few studies have globally evaluated the future costs of adaptation in coastal areas. This study tries to globally analyze the cost of adaptation in coastal areas. First, global distributions of projected inundation impacts induced by SLR including astronomical high tide were assessed. Economic damage was estimated on the basis of the econometric relationship between past hydrological disasters, affected population, and per capita GDP using CRED's EM-DAT database. Second, the cost of adaptation was also determined using the cost database and future scenarios. The authors have built a cost database for installed coastal dykes worldwide and applied it to estimating the future cost of adaptation. The unit costs of dyke construction will increase with socio-economic scenario (SSP) such as per capita GDP. Length of vulnerable coastline is calculated by identifying inundation areas using ETOPO1. Future cost was obtained by multiplying the length of vulnerable coastline and the unit cost of dyke construction. Third, the effectiveness of dyke construction was estimated by comparing cases with and without adaptation.As a result, it was found that incremental adaptation cost is lower than economic damage in the cases of SSP1 and SSP3 under RCP scenario, while the cost of adaptation depends on the durability of the coastal dykes.

Katherine Dykes | NREL

Science.gov Websites

Smarter Cities Marketing Insights 2.0 initiative, a data quality analyst at EnerNOC for its demand wind energy as a wind program analyst for Green Energy Ohio in 2005 and as a data analyst for The

Alcoholism and Alcohol Abuse - Multiple Languages

MedlinePlus

... Affect the Body - العربية (Arabic) PDF Karen Chemical Dependency Taskforce of Minnesota Strong Family Relationships Can Prevent ... Use Among Teens - العربية (Arabic) PDF Karen Chemical Dependency Taskforce of Minnesota Substance Abuse or Dependence - العربية ( ...

Drug Abuse - Multiple Languages

MedlinePlus

... Facts about Marijuana - العربية (Arabic) PDF Karen Chemical Dependency Taskforce of Minnesota Facts about Methamphetamine - English PDF Facts about Methamphetamine - العربية (Arabic) PDF Karen Chemical Dependency Taskforce of Minnesota Substance Abuse or Dependence - العربية ( ...

Curricular Pillars in the Elementary General Music Classroom

ERIC Educational Resources Information Center

Howell, Allen C.

2009-01-01

Karen, a veteran elementary general music teacher, was bewildered when she learned that none of her students remembered "Peter and the Wolf," a music lesson they have encountered in the past. Conscientious beginning elementary general music teachers like Karen may work diligently to plan instruction that will ensure that national, state, and local…

On our need to move beyond folk medicine: A commentary on Karen Gubb's paper, "Psychosomatics today: a review of contemporary theory and practice".

PubMed

Gottlieb, Richard M

2013-02-01

In her thoughtful review and synthesis, Karen Gubb overstimates the breadth of resurgent interest among psychoanalysts in psychosomatic medicine. Such a modest revival as there has been reflects primarily the activity of a few authors and editors. Still, after several decades of inactivity following the intense excitement about this subject during the 1940s and 1950s, there has been some renewal of interest, primarily in Europe and among a small group in the United States. The golden age of psychoanalytic psychosomatics came to an end with the failure to find evidence in support of the promising but overly simplistic specificity theories, especially those of Franz Alexander. If we were going to better understand the complex relations between bodily states (including illnesses) and mental phenomena new theories and modes of investigation would be required. Many apparently new theories have been put forward over the past few decades. Of these, Gubb focuses her attention on two that relate somatic illness to failures in linguistic or symbolic elaboration, that is, to failures in the working over or binding of somatic excitations by the mental apparatus. These theories share the attractive feature that they seem consistent with the claim that psychosomatically ill patients are impaired in their language capacities, being unable to put feelings into words (alexithymia) and unable to move to abstract from concrete thinking (pensée opératoire). While apparently new, when closely examined these theories turn out to be but minor variations of one of Freud's own fundamental theories of mind/body, the one explicated in The Interpretation of Dreams and based upon the neurological model of the reflex arc as known in the 19th century. We know too much today about neuronal functioning, brain operations, and the importance of our subtle interactions with others to be satisfied with a superannuated scientific model. If we analysts are to lay claim to a science beyond a quaint

Flu - Multiple Languages

MedlinePlus

... فارسی) French (français) Hindi (हिन्दी) Hmong (Hmoob) Japanese (日本語) Karen (S’gaw Karen) Khmer (ភាសាខ្មែ ... Poster - Hmoob (Hmong) PDF Minnesota Department of Health Japanese (日本語) Expand Section Home Care for Pandemic Flu - ...

#WomenInSTEM: Identifying an Opportunity for Change

ScienceCinema

Lefkowitz, Karen

2018-01-16

Karen Lefkowitz remembers being the only woman in the room thirty years ago at a conference when she started her career off as a computer programmer. Karen is a firm supporter of mentors and states that women, no matter whether they're in science or any other career, should ask for someone to mentor them. Karen is currently Vice President of Business Transformation at Pepco Holdings, Inc. She is responsible for the deployment of Advanced Metering Infrastructure (AMI) meters, a Department of Energy funded project, in Delaware, DC and Maryland. The meters have a two-way wireless communication that provides hourly consumption data at the premise allowing customers to take control of their energy use.

Anatomy of a frozen axial melt lens from a fast-spreading paleo-ridge (Wadi Gideah, Oman ophiolite)

NASA Astrophysics Data System (ADS)

Müller, T.; Koepke, J.; Garbe-Schönberg, C.-D.; Dietrich, M.; Bauer, U.; Wolff, P. E.

2017-02-01

At fast-spreading mid-ocean ridges, axial melt lenses (AMLs) sandwiched between the sheeted dyke section and the uppermost gabbros are assumed to be the major magma source of crust formation. Here, we present our results from a field study based on a single outcrop of a frozen AML in the Samail ophiolite in the Sultanate of Oman which presents a whole suite of different lithologies and complex cutting relationships: varitextured gabbro with relics of primitive poikilitic clinopyroxene is intruded by massive quartz diorites and tonalites bearing relics of assimilated sheeted dykes, which in turn are cut by trondhjemite dykes. The whole is cut by basaltic dykes with chilled margins. The geochemical evolutionary trend of the varitextured gabbros, including some of the quartz diorites and tonalites, can be best modelled by fractional crystallisation of an experimental MORB parental melt composition containing 0.4 to 0.8 wt.% H2O. Patchy varitextured gabbros containing domains of primitive poikilitic clinopyroxene and evolved granular networks represent the record of in situ crystallisation. Some quartz diorites, often with xenoliths of sheeted dykes and exceptionally high Al2O3 contents, show a bulk trace element pattern more in accord with melts generated by experimental partial melting of dyke material. Highly evolved, crosscutting trondhjemite dykes show characteristic trace element patterns implying a formation by partial melting of sheeted dykes under lower water activity which is indicated by relatively low Al2O3 contents. The late basaltic dykes with chilled margins crosscutting all other lithologies show a relatively depleted geochemical character with pronounced negative Nb-Ta anomalies implying a genetic relationship to the second phase of magmatic Oman paleo-ridge activity (V2). The field relationships in combination with the petrological/geochemical trends reveal multiple sequences of MORB-type magma cooling (resulting in fractional crystallisation) and re

Health Information in Sudanese (Arabic dialect) (سودانية عربية)

MedlinePlus

... سودانية عربية (Sudanese (Arabic dialect)) MP3 Karen Chemical Dependency Taskforce of Minnesota How Beer and Alcohol Affect ... سودانية عربية (Sudanese (Arabic dialect)) MP3 Karen Chemical Dependency Taskforce of Minnesota Alcoholism and Alcohol Abuse How ...

Publications - GMC 413 | Alaska Division of Geological & Geophysical

Science.gov Websites

Surveys Skip to content State of Alaska myAlaska My Government Resident Business in Alaska Spectrometer) data of Triassic and Carboniferous outcrop samples from the Karen Creek, Ivishak, and Nuka Resolution ICP Mass Spectrometer) data of Triassic and Carboniferous outcrop samples from the Karen Creek

Physiological and Growth Characteristics of Shewanella Species

DTIC Science & Technology

2016-05-01

AFCEC-CX-TY-TR-2016-0016 PHYSIOLOGICAL AND GROWTH CHARACTERISTICS OF SHEWANELLA SPECIES Karen Farrington, D. Matthew Eby, Susan Sizemore...Technical Report 01 March 2012 - 01 March 2014 Physiological and growth characteristics of Shewanella species FA4819-11-C-0003 Karen Farrington (1...unconventional operating temperatures. Secondly, the unusual growth characteristics of another Shewanella sp., Shewanella japonica, were investigated

Child Safety - Multiple Languages

MedlinePlus

... Cantonese dialect) (繁體中文) French (français) Hindi (हिन्दी) Japanese (日本語) Karen (S’gaw Karen) Korean (한국어) Nepali (नेपा ... हिन्दी (Hindi) Bilingual PDF Health Information Translations Japanese (日本語) Expand Section Child Safety Checklist - 日本語 (Japanese) ...

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, holds a sample of the sea grass she collected from the floor of the Banana River. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

NASA Image and Video Library

2004-02-05

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, holds a sample of the sea grass she collected from the floor of the Banana River. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

KENNEDY SPACE CENTER, FLA. - As Karen Holloway-Adkins, KSC wildlife specialist, begins a tour of the Banana River, this alligator sunning itself attracts attention. Holloway-Adkins is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

NASA Image and Video Library

2004-02-05

KENNEDY SPACE CENTER, FLA. - As Karen Holloway-Adkins, KSC wildlife specialist, begins a tour of the Banana River, this alligator sunning itself attracts attention. Holloway-Adkins is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, shows a sample of the sea grass she collected from the floor of the Banana River. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

NASA Image and Video Library

2004-02-05

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, shows a sample of the sea grass she collected from the floor of the Banana River. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, at the helm of a boat on the Banana River, heads for a research area. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

NASA Image and Video Library

2004-02-05

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, at the helm of a boat on the Banana River, heads for a research area. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, takes the helm on the boat as she begins a tour of the Banana River. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

NASA Image and Video Library

2004-02-05

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, takes the helm on the boat as she begins a tour of the Banana River. She is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

Monitoring of suspended sediment variation using Landsat and MODIS in the Saemangeum coastal area of Korea.

PubMed

Min, Jee-Eun; Ryu, Joo-Hyung; Lee, Seok; Son, Seunghyun

2012-02-01

Suspended sediment concentration (SS) is an important indicator of marine environmental changes due to natural causes such as tides, tidal currents, and river discharges, as well as human activities such as construction in coastal regions. In the Saemangeum area on the west coast of Korea, construction of a huge tidal dyke for land reclamation has strongly influenced the coastal environment. This study used remotely sensed data to analyze the SS changes in coastal waters caused by the dyke construction. Landsat and MODIS satellite images were used for the spatial analysis of finer patterns and for the detailed temporal analysis, respectively. Forty Landsat scenes and 105 monthly composite MODIS images observed during 1985-2010 were employed, and four field campaigns (from 2005 to 2006) were performed to verify the image-derived SS. The results of the satellite data analyses showed that the seawater was clear before the dyke construction, with SS values lower than 20 g/m(3). These values increased continuously as the dyke construction progressed. The maximum SS values appeared just before completion of the fourth dyke. Values decreased to below 5 g/m(3) after dyke construction. These changes indicated tidal current modification. Some eddies and plumes were observed in the images generated from Landsat data. Landsat and MODIS can reveal that coastal water turbidity was greatly reduced after completion of the construction. Copyright © 2011 Elsevier Ltd. All rights reserved.

AfricaArray International Geophysics Field School: Applications of Near Surface Geophysics to challenges encountered in mine planning

NASA Astrophysics Data System (ADS)

Webb, S. J.; Jones, M. Q.; Durrheim, R. J.; Nyblade, A.; Snyman, Q.

2012-12-01

Hard rock exploration and mining presents many opportunities for the effective use of near surface geophysics. For over 10 years the AfricaArray international geophysics field school has been hosted at a variety of mines in South Africa. While the main objective of the field school is practical training for the next generation of geophysicists, being hosted at a mine has allowed us to investigate applications of near surface geophysics in the early stages of mine planning and development as geophysics is often cheaper and faster than drilling. Several applications include: detailed delineation of dykes and stringer dykes, physical property measurements on drill core for modeling and marker horizons, determination of overburden thickness, locations of water and faults. Dolerite dykes are usually magnetic and are associated with loss of ground (i.e. where the dyke replaces the ore and thus reduces the amount of ore available) and safety/stability concerns. Thus the accurate mapping of dykes and narrow stringers that are associated with them are crucial to the safe planning of a mine. We have acquired several case studies where ground magnetic surveys have greatly improved on the resolution and detail of airborne magnetic surveys in regions of complicated dyke swarms. In many cases, thin stringer dykes of less than 5 cm have been detected. Physical property measurements of these dykes can be used to distinguish between different ages of dykes. It is important to accurately determine overburden thickness when planning an open pit mine as this directly affects the cost of development. Depending on the nature of the overburden, both refraction seismic and or DC resistivity can provide continuous profiling in the area of interest that fills in gaps between boreholes. DC resistivity is also effective for determining water associated with dykes and structures that may affect mine planning. The field school mainly addresses the training of a variety of students. The core

Healthy Sleep - Multiple Languages

MedlinePlus

... 繁體中文) Farsi (فارسی) French (français) Hindi (हिन्दी) Japanese (日本語) Karen (S’gaw Karen) Korean (한국어) Nepali (नेपा ... हिन्दी (Hindi) Bilingual PDF Health Information Translations Japanese (日本語) Expand Section Common Sleep Problems - 日本語 (Japanese) ...

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

Lefkowitz, Karen

Karen Lefkowitz remembers being the only woman in the room thirty years ago at a conference when she started her career off as a computer programmer. Karen is a firm supporter of mentors and states that women, no matter whether they're in science or any other career, should ask for someone to mentor them. Karen is currently Vice President of Business Transformation at Pepco Holdings, Inc. She is responsible for the deployment of Advanced Metering Infrastructure (AMI) meters, a Department of Energy funded project, in Delaware, DC and Maryland. The meters have a two-way wireless communication that provides hourly consumptionmore » data at the premise allowing customers to take control of their energy use.« less

Forecasting magma-chamber rupture at Santorini volcano, Greece.

PubMed

Browning, John; Drymoni, Kyriaki; Gudmundsson, Agust

2015-10-28

How much magma needs to be added to a shallow magma chamber to cause rupture, dyke injection, and a potential eruption? Models that yield reliable answers to this question are needed in order to facilitate eruption forecasting. Development of a long-lived shallow magma chamber requires periodic influx of magmas from a parental body at depth. This redistribution process does not necessarily cause an eruption but produces a net volume change that can be measured geodetically by inversion techniques. Using continuum-mechanics and fracture-mechanics principles, we calculate the amount of magma contained at shallow depth beneath Santorini volcano, Greece. We demonstrate through structural analysis of dykes exposed within the Santorini caldera, previously published data on the volume of recent eruptions, and geodetic measurements of the 2011-2012 unrest period, that the measured 0.02% increase in volume of Santorini's shallow magma chamber was associated with magmatic excess pressure increase of around 1.1 MPa. This excess pressure was high enough to bring the chamber roof close to rupture and dyke injection. For volcanoes with known typical extrusion and intrusion (dyke) volumes, the new methodology presented here makes it possible to forecast the conditions for magma-chamber failure and dyke injection at any geodetically well-monitored volcano.

Forecasting magma-chamber rupture at Santorini volcano, Greece

PubMed Central

Browning, John; Drymoni, Kyriaki; Gudmundsson, Agust

2015-01-01

How much magma needs to be added to a shallow magma chamber to cause rupture, dyke injection, and a potential eruption? Models that yield reliable answers to this question are needed in order to facilitate eruption forecasting. Development of a long-lived shallow magma chamber requires periodic influx of magmas from a parental body at depth. This redistribution process does not necessarily cause an eruption but produces a net volume change that can be measured geodetically by inversion techniques. Using continuum-mechanics and fracture-mechanics principles, we calculate the amount of magma contained at shallow depth beneath Santorini volcano, Greece. We demonstrate through structural analysis of dykes exposed within the Santorini caldera, previously published data on the volume of recent eruptions, and geodetic measurements of the 2011–2012 unrest period, that the measured 0.02% increase in volume of Santorini’s shallow magma chamber was associated with magmatic excess pressure increase of around 1.1 MPa. This excess pressure was high enough to bring the chamber roof close to rupture and dyke injection. For volcanoes with known typical extrusion and intrusion (dyke) volumes, the new methodology presented here makes it possible to forecast the conditions for magma-chamber failure and dyke injection at any geodetically well-monitored volcano. PMID:26507183

Sr isotopic tracer study of the Samail ophiolite, Oman.

USGS Publications Warehouse

Lanphere, M.A.; Coleman, R.G.; Hopson, C.A.

1981-01-01

Rb and Sr concentrations and Sr-isotopic compositions were measured in 41 whole-rock samples and 12 mineral separates from units of the Samail ophiolite, including peridotite, gabbro, plagiogranite, diabase dykes, and gabbro and websterite dykes within the metamorphic peridotite. Ten samples of cumulate gabbro from the Wadir Kadir section and nine samples from the Wadi Khafifah section have 87Sr/86Sr ratios of 0.70314 + or - 0.00030 and 0.70306 + or - 0.00034, respectively. The dispersion in Sr- isotopic composition may reflect real heterogeneities in the magma source region. The average Sr-isotopic composition of cumulate gabbro falls in the range of isotopic compositions of modern MORB. The 87Sr/86Sr ratios of noncumulate gabbro, plagiogranite, and diabase dykes range 0.7034-0.7047, 0.7038-0.7046 and 0.7037- 0.7061, respectively. These higher 87Sr/86Sr ratios are due to alteration of initial magmatic compositions by hydrothermal exchange with sea-water. Mineral separates from dykes that cut harzburgite tectonite have Sr-isotopic compositions which agree with that of cumulate gabbro. These data indicate that the cumulate gabbro and the different dykes were derived from partial melting of source regions that had similar long-term histories and chemical compositions.-T.R.

The Continent-Ocean Transition in the Mid-Norwegian Margin: Insight From Seismic Data and the Onshore Caledonian Analogue in the Seve Nappe Complex

NASA Astrophysics Data System (ADS)

Abdelmalak, Mansour M.; Planke, Sverre; Andersen, Torgeir B.; Faleide, Jan Inge; Corfu, Fernando; Tegner, Christian; Myklebust, Reidun

2015-04-01

The continental breakup and initial seafloor spreading in the NE Atlantic was accompanied by widespread intrusive and extrusive magmatism and the formation of conjugate volcanic passive margins. These margins are characterized by the presence of seaward dipping reflectors (SDR), an intense network of mafic sheet intrusions of the continental crust and adjacent sedimentary basins and a high-velocity lower crustal body. Nevertheless many issues remain unclear regarding the structure of volcanic passive margins; in particular the transitional crust located beneath the SDR.New and reprocessed seismic reflection data on the Mid-Norwegian margin allow a better sub-basalt imaging of the transitional crust located beneath the SDR. Different high-amplitude reflections with abrupt termination and saucer shaped geometries are identified and interpreted as sill intrusions. Other near vertical and inclined reflections are interpreted as dykes or dyke swarms. We have mapped the extent of the dyke reflections along the volcanic margin. The mapping suggests that the dykes represent the main feeder system for the SDR. The identification of saucer shaped sills implies the presence of sediments in the transitional zone beneath the volcanic sequences. Onshore exposures of Precambrian basement of the eroded volcanic margin in East Greenland show that, locally, the transitional crust is highly intruded by dykes and intrusive complexes with an increasing intensity of the plumbing and dilatation of the continental crust ocean-ward. Another well exposed analogue for a continent-ocean transitional crust is located within the Seve Nappe Complex (SNC) of the Scandinavian Caledonides. The best-preserved parts of SNC in the Pårte, Sarek, Kebnekaise, Abisko, and Indre Troms mountains are composed mainly of meta-sandstones and shales (now hornfelses) truncated typically by mafic dykes. At Sarek and Pårte, the dykes intrude the sedimentary rocks of the Favoritkammen Group, with a dyke density up

Insecticide Exposure in Parkinsonism

DTIC Science & Technology

2006-01-01

Chlorpyrifos or Permethrin Exposures, fall 2000, National Meeting of the Society for Environmental Toxicology and Chemistry , Nashville, Tennessee. D. Karen...Biomarkers, fall 2000, National Meeting of the Society for Environmental Toxicology and Chemistry , Nashville, Tennessee. D. Karen, W. Li, P. Harp, J...by the U.S. Army, contract DAMD-17-98-1-8633. Abstracts for Society of Environmental Toxicology and Chemistry meeting, Fall, 2000: Murine

The National Water-Quality Assessment Program Invertebrate Data Analysis System (IDAS) Software: Version 3 (User’s Manual)

DTIC Science & Technology

2003-01-01

Steven Goodbred, Martin Gurtz, Evan Hornig, Clifford Hupp, Terry Maret , Michael Meador, Bruce Moring, Mark Munn, Karen Murray, James Petersen...Zappia, James Coles, Ian Waite, Thomas Abrahamsen, Elise Giddings, Robert Ourso, Mitch Harris, Terry Maret , Dorene MacCoy, Karen Murray, and...appropriate user manuals or online help: http://www.microsoft.com CAUTION: The installation package will alert you when it tries to replace an existing

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, searches the Banana River for a grass specimen. In the background is one of the launch pads. The biologist is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

NASA Image and Video Library

2004-02-05

KENNEDY SPACE CENTER, FLA. - Karen Holloway-Adkins, KSC wildlife specialist, searches the Banana River for a grass specimen. In the background is one of the launch pads. The biologist is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

KENNEDY SPACE CENTER, FLA. - From a boat on the Banana River the Vehicle Assembly Building looms over the water. The boat holds Karen Holloway-Adkins, KSC wildlife specialist, who is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

NASA Image and Video Library

2004-02-05

KENNEDY SPACE CENTER, FLA. - From a boat on the Banana River the Vehicle Assembly Building looms over the water. The boat holds Karen Holloway-Adkins, KSC wildlife specialist, who is studying the life history of sea turtles, especially what they eat, where they lay their eggs and what factors might harm their survival. On the boat trip she is also monitoring the growth of sea grasses and algae and the water quality of estuaries and lagoons used by sea turtles and other aquatic wildlife.

Hydrothermal Alteration of the Mt Unzen Conduit (Shimabara/Japan)

NASA Astrophysics Data System (ADS)

Yilmaz, T. I.; Mayer, K.; Hess, K. U.; Janots, E.; Gilg, H. A.; Dingwell, D. B.

2016-12-01

Investigations were carried out on hydrothermally altered coherent dacitic dykes samples from (USDP-4) drill core at Mt Unzen stratovolcano (Shimabara/Japan). XRF, XRD, EMPA, and C-O-isotope analysis led to insights concerning chemistry, mineralogy, and intensity of alteration as well as the origin of carbonate-precipitating fluids. Additionally a textural characterization of the occurring replacement features in the magma conduit zone was performed. The occurrence of the main secondary phases such as chlorite, pyrite, carbonates, and R1 (Reichweite parameter) illite-smectite indicate a weak to moderate propylitic to phyllic hydrothermal alteration. The dacitic samples of the dykes show different hydrothermal alteration features: (i) carbonate pseudomorphs after hornblende as well as core and zonal textures due to replacement of plagioclase by R1 illite-smectite, (ii) colloform banded fracture fillings and fillings in dissolution vugs, and (iii) chlorite and R1 illite-smectite in the groundmass. Carbonates in fractures comprise iron-rich dolomite solid solutions ("ankerite") and calcite. Isotopic values of d13Cvpdb = -4.59 ± 0.6‰ and d18Ovpdb = -21.73 ± 0.5‰ indicate a hydrothermal-magmatic origin for the carbonate formation. The chlorite-carbonate-pyrite index (CCPI) and the Ishikawa alteration index (AI), applied to the investigated samples show significant differences (CCPI=52.7-57.8; AI=36.1-40.6) indicating their different degree of alteration. According to Nakada et al., 2005, the C13 to C16 dykes represent the feeder dyke from the latest eruption (1991-1995) whereas C8 represents an earlier dyke feeder dyke from an older eruption. Weakest conduit alteration, which was obtained in samples C16-1-5 and C13-2-5, correlates with the alteration degree of the pristine dome rocks. Highest CCPI value was determined for sample C14-1-5 and the highest AI value was determined for sample C15-2-6. The degrees of alteration do not indicate highest alteration of the

Further geochronological and paleomagnetic constraints on Malani (and pre-Malani) magmatism in NW India

NASA Astrophysics Data System (ADS)

Meert, Joseph G.; Pandit, Manoj K.; Kamenov, George D.

2013-11-01

At 750 Ma India was part of a larger fragment of eastern Gondwana blocks that included the Seychelles-Mauritia, Madagascar, Sri Lanka and the Enderby Land-Prydz Bay region of East Antarctica. Subduction of the Mozambique Ocean beneath Seychelles-Mauritia, northern Madagascar and northwestern India formed a lengthy continental arc that remained active during the formation of Gondwana. Paleomagnetic data from the Malani rhyolites and associated dykes provide a robust paleomagnetic pole constraining India's position at this time. The rhyolitic and granitic rocks associated with the Malani Igneous Suite (MIS) have robust age constraints; however, the ages of the mafic dykes were inferred solely on the basis of similarity in paleomagnetic directions to the rhyolitic units. Here we present new geochronological data from the Malani mafic dykes that yield a minimum age of 704 Ma. The 207Pb/206Pb ages obtained for the dykes are less-likely to be affected by Pb-loss and yield a more reliable estimate for the age of the mafic dykes of ~ 750 Ma. We argue that intrusion of these mafic (and minor felsic) dykes represents the final pulse of MIS magmatism. Many of the granitic rocks in the region are reported as ‘unclassified’ due to limited geochemical data and/or geochronological ages. Some of these ‘unclassified’ granites are intruded by the mafic dykes sampled in this study near the town of Bilara. The granites yielded zircon core ages of ~ 1100 Ma with younger rims averaging ~ 1020 Ma. We argue that this provides further evidence for a significant orogenic event ~ 1000 Ma that may relate to the collision of the Marwar block with the Banded Gneiss Complex/Bundelkhand craton in north-central India. Other ~ 1000 Ma orogenesis is also known along the Central Indian Tectonic Zone (CITZ) and the Eastern Ghats Mobile Belt. Globally, this same time interval is thought to represent the amalgamation of the supercontinent Rodinia and may also have resulted in the closure of the

Assuring Force Readiness and Beneficiary Health Through Health Promotion and Preventive Medicine in the Military Health System

DTIC Science & Technology

1998-04-06

Randolph L. Gordon, Karen E. White, Paul V. Stange, and Sabrina M. Harper, "Prevention and Managed Care: Opportunities for Managed Care Organizations...dominol.hcssa.amedd.army.mil/default.htm; Internet. 1,3 Gail Maestas , COL, USA. "Executive Information Systems: The Future," (Paper presented at The...Karen E. White, Paul V. Stange, and Sabrina M. Harper.]. "Prevention and Managed Care: Opportunities for Managed Care Organizations, Purchasers, of

Safety - Multiple Languages

MedlinePlus

... sharing features on this page, please enable JavaScript. Arabic (العربية) Bosnian (bosanski) Burmese (myanma bhasa) Chinese, Simplified ( ... 日本語) Karen (S’gaw Karen) Korean (한국어) Modern Standard Arabic (Arabic dialect) (العربية الفصحى, عربي فصيح) Russian (Русский) ...

Suitability Screening Test for Marine Corps Air Traffic Controllers Phase 2

DTIC Science & Technology

2013-06-10

Karen M. Walker, Ph.D. William L. Farmer, Ph.D. Rebecca C. Roberts, MS Navy Personnel Research, Studies, and Technology NPRST-TR-13-2...June 2013 Suitability Screening Test for Marine Corps Air Traffic Controllers Phase II Karen M. Walker, Ph.D. William L. Farmer, Ph.D. Rebecca...C. Roberts, MS Navy Personnel Research, Studies, and Technology Reviewed by Tanja Blackstone , Ph.D. Approved and released by D. M. Cashbaugh

Suitability Screening Test for Marine Corps Air Traffic Controllers. Phase 2

DTIC Science & Technology

2013-06-01

Karen M. Walker, Ph.D. William L. Farmer, Ph.D. Rebecca C. Roberts, MS Navy Personnel Research, Studies, and Technology NPRST-TR-13-2...June 2013 Suitability Screening Test for Marine Corps Air Traffic Controllers Phase II Karen M. Walker, Ph.D. William L. Farmer, Ph.D. Rebecca...C. Roberts, MS Navy Personnel Research, Studies, and Technology Reviewed by Tanja Blackstone , Ph.D. Approved and released by D. M. Cashbaugh

Fluvial landscapes - human societies interactions during the last 2000 years: the Middle Loire River and its embanking since the Middle Ages (France)

NASA Astrophysics Data System (ADS)

Castanet, Cyril; Carcaud, Nathalie

2015-04-01

This research deals with the study of fluvial landscapes, heavily and precociously transformed by societies (fluvial anthroposystems). It aims to characterize i), fluvial responses to climate, environmental and anthropogenic changes ii), history of hydraulical constructions relative to rivers iii), history of fluvial origin risks and their management - (Program: AGES Ancient Geomorphological EvolutionS of the Loire River hydrosystem). The Middle Loire River valley in the Val d'Orléans was strongly and precociously occupied, particularly during historical periods. Hydrosedimentary flows are there irregular. The river dykes were built during the Middle Ages (dykes named turcies) and the Modern Period, but ages and localizations of the oldest dykes were not precisely known. A systemic and multi-scaled approach aimed to characterize i), palaeo-hydrographical, -hydrological and -hydraulical evolutions of the Loire River, fluvial risks (palaeo-hazards and -vulnerabilities) and their management. It is based on an integrated approach, in and out archaeological sites: morpho-stratigraphy, sedimentology, geophysics, geochemistry, geomatics, geochronology, archaeology. Spatio-temporal variability of fluvial hazards is characterized. A model of the Loire River fluvial activity is developed: multicentennial scale variability, with higher fluvial activity episodes during the Gallo-Roman period, IX-XIth centuries and LIA. Fluvial patterns changes are indentified. Settlement dynamics and hydraulical constructions of the valley are specified. We establish the ages and localizations of the oldest discovered dikes of the Middle Loire River: after the Late Antiquity and before the end of the Early Middle Ages (2 dated dykes), between Bou and Orléans cities. During historical periods, we suggest 2 main thresholds concerning socio-environmental interactions: the first one during the Early Middle Ages (turcies: small scattered dykes), the second during the Modern Period (levees: high

A precisely dated Proterozoic palaeomagnetic pole from the North China craton, and its relevance to palaeocontinental reconstruction

NASA Astrophysics Data System (ADS)

Halls, Henry C.; Li, Jianghai; Davis, Don; Hou, Guiting; Zhang, Baoxing; Qian, Xianglin

2000-10-01

A palaeomagnetic pole position, derived from a precisely dated primary remanence, with minimal uncertainties due to secular variation and structural correction, has been obtained for China's largest dyke swarm, which trends for about 1000km in a NNW direction across the North China craton. Positive palaeomagnetic contact tests on two dykes signify that the remanent magnetization is primary and formed during initial cooling of the intrusions. The age of one of these dykes, based on U-Pb dating of primary zircon, is 1769.1+/-2.5Ma. The mean palaeomagnetic direction for 19 dykes, after structural correction, is D=36°, I=-5°, k=63, α95=4°, yielding a palaeomagnetic pole at Plat=36°N, Plong=247°E, dp=2°, dm=4° and a palaeolatitude of 2.6°S. Comparison of this pole position with others of similar age from the Canadian Shield allows a continental reconstruction that is compatible with a more or less unchanged configuration of Laurentia, Siberia and the North China craton since about 1800Ma

Sodium metasomatism along the Melones fault zone, Sierra Nevada foothills, California, USA

USGS Publications Warehouse

Albino, G.V.

1995-01-01

Albitite, locally aegirine- and riebeckite-bearing, formed as a result of sodium metasomatism of felsic dykes and argillites along the Melones Fault Zone near Jamestown, California. Pyrite, magnetite, hematite and titanite are common in small amounts in altered dykes. The dykes were originally plagioclase-hornblende porphyritic, and had major and trace element abundances typical of calc-alkaline rocks, whereas they now have Na2O contents as high as 11.40%. Mass balance calculations indicate that alteration involved addition of large amounts of sodium, and the removal of SiO2 and K2O. Textural preservation, combined with volume factors calculated from specific gravity and whole rock analytical data, indicate that Na-metasomatism was essentially isovolumetric. -from Author

Geochemistry and Ar-Ar muscovite ages of the Daraban Leucogranite, Mawat Ophiolite, northeastern Iraq: Implications for Arabia-Eurasia continental collision

NASA Astrophysics Data System (ADS)

Mohammad, Yousif O.; Cornell, David H.; Qaradaghi, Jabbar H.; Mohammad, Fahmy O.

2014-06-01

Daraban Leucogranite dykes intruded discordantly into the basal serpentinized harzburgite of the Mawat Ophiolite, Kurdistan region, NE Iraq. These coarse grained muscovite-tourmaline leucogranites are the first leucogranite dykes identified within the Mawat Ophiolite. They are mainly composed of quartz, K-feldspar, plagioclase, tourmaline, muscovite, and secondary phologopite, while zircon, xenotime, corundum, mangano-ilemnite and cassiterite occur as accessories.

Chemistry, mineralogy and alteration intensity of hydrothermal altered Mt Unzen conduit rocks (Shimabara/Japan)

NASA Astrophysics Data System (ADS)

Hess, Kai-Uwe; Yilmaz, Tim; Gilg, H. Albert; Janots, Emilie; Mayer, Klaus; Nakada, Setsuya; Dingwell, Donald

2017-04-01

Investigations were carried out on hydrothermally altered coherent dacitic dykes samples from (USDP-4) drill core at Mt Unzen stratovolcano (Shimabara/Japan). XRF, XRD, EMPA, C-O-isotope, hot-cathode CL and SEM analysis led to insights concerning chemistry, mineralogy, and intensity and type of alteration as well as the origin of carbonate-precipitating fluids. Additionally a textural characterization of the occurring replacement features in the volcanic conduit rocks was performed. The occurrence of the main secondary phases such as chlorite, pyrite, carbonates, and R1 (Reichweite parameter) illite-smectite and kaolinite group minerals indicate a weak to moderate propylitic to phyllic hydrothermal alteration. The dacitic samples of the dykes show different hydrothermal alteration features: (i) carbonate and chlorite pseudomorphs after hornblende as well as core and zonal textures due to replacement of plagioclase by R1 illite-smectite as well as kaolinite group minerals, (ii) colloform banded fracture fillings and fillings in dissolution vugs, and (iii) chlorite, R1 illite-smectite as well as kaolinite group minerals in the groundmass. Late chlorite veins crosscut precipitates of R1 illite-smectite as well as kaolinite group minerals. Carbonates in fractures and in pseudomorphs after hornblende comprise iron-rich dolomite solid solutions ("ankerite") and calcite. Isotopic values indicate a hydrothermal-magmatic origin for the carbonate formation. The chlorite-carbonate-pyrite index (CCPI) and the Ishikawa alteration index (AI), applied to the investigated samples show significant differences (CCPI=52.7-57.8; AI=36.1-40.6) indicating their different degree of alteration. According to Nakada et al., 2005, the C13 to C16 dykes represent the feeder dyke from the latest eruption (1991-1995) whereas C8 represents an earlier dyke feeder dyke from an older eruption. Weakest alteration, which was obtained in samples C16-1-5 and C13-2-5, correlates with the alteration

A Late Mesozoic short-lived shift from fluid-dominated to sediment-dominated mantle metasomatism in the northeast South China Block and its tectonic implications

NASA Astrophysics Data System (ADS)

Pan, Fa-Bin; Jin, Chong; Jia, Bao-Jian; Liu, Rong; He, Xiaobo; Gao, Zhong; Tao, Lu; Zhou, Xiao-Chun; Zhang, Li-Qi

2018-06-01

Early Cretaceous northwest (NW)-trending dolerite and amphibole lamprophyre dykes exposed in NW Zhejiang Province provide a number of new insights into the nature of the subcontinental mantle on the northeast (NE) South China Block (SCB). These dykes have a high Al2O3 (14.04-17.89 wt%) and K2O (0.66-2.69 wt%) contents but relatively low Na2O (2.48-4.61 wt%) and TiO2 (1.33-2.79 wt%) makeup alongside moderate K2O/Na2O ratios between 0.26 and 1.04. These amphibole lamprophyre dykes also have higher MgO, Cr, and Ni contents than those of comparable dolerites that have SiO2 content ranging from 46.32 to 49.87 wt%. The most striking feature of these intrusions is that they contain higher contents of Rb, Th, U, Nb, Ta, and LREE compared to their dolerite counterparts, although both amphibole lamprophyres and dolerites do exhibit similar geochemical patterns that are indicative of subduction-related origins. These features imply that an ambient peridotitic mantle that acted as the source for the amphibole lamprophyre magma source may have reacted with silicate-rich melts leading to olivine consumption while maintaining orthopyroxene. The geochemical composition of these dolerites are likely influenced to a variable extent by the fractionation of olivine, orthopyroxene, clinopyroxene, Fe-Ti oxides, and apatite, while their amphibole lamprophyre counterparts have been modified to a minor degree by amphibole fractionation. Measured Sr-Nd isotopic compositions suggest relatively constant Nd isotopic compositions (-0.36 to +1.52) with more variable Sr isotopic compositions (0.7071 to 0.7306). We hence propose that both the dolerite and amphibole lamprophyre dykes in this region are the products of mantle source metasomatism by the subducted Paleo-Pacific slab. The dolerite dykes are mainly associated with slab-derived fluids, while the lamprophyre dykes are related to both slab-derived fluids and sediment melts. Evidence in support of metasomatism comprising distinct two

Feeder systems of acidic lava flows from the Paraná-Etendeka Igneous Province in southern Brazil and their implications for eruption style

NASA Astrophysics Data System (ADS)

de Lima, Evandro Fernandes; Waichel, Breno Leitão; Rossetti, Lucas De Magalhães May; Sommer, Carlos Augusto; Simões, Matheus Silva

2018-01-01

In the Rio Grande do Sul State, southern Brazil, the volcanic sequence of the Paraná-Etendeka Igneous Province consists of pahoehoe and rubbly pahoehoe lava flows with basaltic and basaltic andesitic composition respectively, overlaid by acidic volcanic rocks. The acidic volcanic rocks of the Paraná-Etendeka Igneous Province exhibit textures and structures that can be related to effusive and/or explosive eruptions generating predominantly rheoignimbrites. The huge lava volume related to the emplacement of large igneous provinces implicates on efficient feeder systems that are more commonly observed in continental environments. In the Paraná-Etendeka Igneous Province, feeders of basaltic rocks are exposed in several dyke swarms (Ponta Grossa NW trending, Florianópolis/Skeleton Coast (NW Namibia) N-S trending, Serra do Mar NE trending and Henties Bay/Outjo NE trending). In contrast, the only feeder system proposed to the acidic rocks of the Paraná-Etendeka Igneous Province is the Messum complex in Namibia (Milner et al. 1995). In the study area, the opening of three quarries for the extraction of dimension stones has exposed impressive structures/textures that show the effusive emplacement and the ductile to fragile-ductile magma transition along the acidic feeder dykes. Besides that, magma mixing/mingling processes between two acidic magmas are observed along the dykes. Here we describe new occurrences of acidic feeder dykes, correlate the dykes with acidic flows and discuss their importance to understand the emplacement of the Palmas type acid units in southern Brazil.

Photograph of the Month

NASA Astrophysics Data System (ADS)

2015-04-01

For dykes, magma flow direction can be deciphered from various fabrics in the chilled margin (Correa-Gomez et al., 2001, JSG 23, 1415). This photograph represents part of a chilled margin of a appr. N- S trending dyke at Kharghar Hills, Mumbai, Maharashtra, India. The section is sub-vertical. The elongated grooves indicate flow of magma through a fault and the tapered grooves (arrows) connote the flow direction: towards the pointed end of the groove. The magma flowed towards the north in this case. Such fabrics of wall-magma interaction in the Deccan volcanic province prove that dykes injected along fault planes. 19° 2‧ 22.3″ N, 73° 3‧ 28.7″ E. Photograph Ayan Achyuta Misra, Mumbai, India.

Saint Louis Center for Sustainment of Trauma and Readiness Skills: A Collaborative Air Force-Civilian Trauma Skills Training Program

DTIC Science & Technology

2016-05-19

NUMBER 6. AUTHOR(S) Jason W. Grimm , Karen Johnson 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION...ABSTRACT SAR 18. NUMBER OF PAGES 5 19a. NAME OF RESPONSIBLE PERSON Jason Grimm a. REPORT U b. ABSTRACT U c. THIS PAGE U 19b... Grimm Karen Johns For correspo Vista at Gra J Emerg Nu 0099-1767 Published b http://dx.do ■ ■ • ■SAINT LOUIS CENTER FOR SUSTAINMENT OF TRAUMA AND

Characteristics and Lifestyle Behaviors of Employees Who Work for the Department of Defense

DTIC Science & Technology

1992-03-02

English and Spanish language versions of the instrument is held by Susan Noble Walker, EdD, RN, Karen R. Sechrist, PhD, RN, FAAN and Nola J. Pender , PhD...Promoting Lifestyle Profile and wish you much success with your efforts. Sincerely,en Susan Noble Walker Karen R. Sechrist Nola J. Pender 40 Appendix C...have a significant impact on health status and are an integral part of one’s pattern of living ( Pender , Sechrist, Stromberg & Walker, 1990). Operational

Thermal Expansivity Between 150 and 800°C of Hydrothermally Altered Conduit Dyke Samples from USDP-4 Drill Core (Mt Unzen, Shimabara, Japan)

NASA Astrophysics Data System (ADS)

Yilmaz, T. I.; Hess, K. U.; Vasseur, J.; Wadsworth, F. B.; Gilg, H. A.; Nakada, S.; Dingwell, D. B.

2017-12-01

When hot magma intrudes the crust, the surrounding rocks expand. Similarly, the cooling magma contracts. The expansion and contraction of these multiphase materials is not simple and often requires empirical constraint. Therefore, we constrained the thermal expansivity of Unzen dome and conduit samples using a NETZSCH® DIL 402C. Following experiments, those samples were scanned using a Phoenix v|tome|x m to observe the cracks that may have developed during the heating and cooling. The dome samples do not show petrological or chemical signs of alteration. However, the alteration of the conduit dykes is represented by the occurrence of the main secondary phases such as chlorite, sulfides, carbonates, R1 (Reichweite parameter) illite-smectite, and kaolinite. These alteration products indicate an (I) early weak to moderate argillic magmatic alteration, and a (II) second stage weak to moderate propylitic hydrothermal alteration. The linear thermal expansion coefficient aL of the dome material is K-1 between 150° and 800°C and shows a sharp peak of up to K-1 around the alpha-beta-quartz-transition ( 573°C). In contrast, aL of the hydrothermally altered conduit samples starts to increase around 180° and reaches K-1 at 400°C. We interpret this effect as being due to the water content of the kaolinite and the R1 illite-smectite, which induces larger expansions per degree temperature change. Furthermore, the altered conduit samples show a more pronounced increases of aL between 500 and 650°C of up to peaks at K-1, which is generated by the breakdown of chlorite, iron-rich dolomite solid solutions, calcite, and pyrite. We use a 1D conductive model of heat transfer to explore how the country rock around the Unzen conduit zone would heat up after intrusion. In turn, we convert these temperature profiles to thermal stress profiles, assuming the edifice is largely undeformable. We show that these high linear thermal expansion coefficients of the hydrothermally altered

New evidence on the accurate displacement along the Arava/Araba segment of the Dead Sea Transform

NASA Astrophysics Data System (ADS)

Beyth, M.; Sagy, A.; Hajazi, H.; Alkhraisha, S.; Mushkin, A.; Ginat, H.

2018-06-01

The sinistral displacement along the Dead Sea Transform (DST), the plate boundary between the African and the Arabian plates, south of the Dead Sea basin, was previously attributed to two main fault zones: the Arava/Araba or Dead Sea fault and the Feinan or Al Quwayra fault zone. This was based on similarities of features on either side of the Araba Valley. In particular, the Timna and the Feinan copper mines, located north of the Themed and Dana faults, and the onlap of the Cambrian formations southward onto the Amram rhyolite and Ahyamir volcanics. To these we add a more accurate offset indicator in the form of an offset Early Cambrian (532 Ma) dolerite dyke previously mapped in Mount Amram (Israel) on the African plate and recently discovered across the Araba Valley in Jabal Sumr al Tayyiba (southwest Jordan) on the Arabian plate. This dolerite dyke is 20 m thick, strikes N50°E and is the only dyke intruding the Jabal Sumr al Tayyiba pink rhyolite flows of the Ahyamir Volcanics. Geochemical and geochronological correlations between the Jabal Sumr al Tayyiba dolerite dyke and the Mount Amram dolerite dyke demonstrate 85 km of sinistral offset across the Arava/Araba fault. Our results also suggest approximately 109 km of combined sinistral displacement across the Arava/Araba and Feinan faults based on petrological correlations between the Timna and Jabal Hanna igneous complexes on the African and Arabian plates, respectively. This constrains the total sinistral displacement of the Feinan fault and its accessory faults to be 24 km.

New evidence on the accurate displacement along the Arava/Araba segment of the Dead Sea Transform

NASA Astrophysics Data System (ADS)

Beyth, M.; Sagy, A.; Hajazi, H.; Alkhraisha, S.; Mushkin, A.; Ginat, H.

2017-11-01

The sinistral displacement along the Dead Sea Transform (DST), the plate boundary between the African and the Arabian plates, south of the Dead Sea basin, was previously attributed to two main fault zones: the Arava/Araba or Dead Sea fault and the Feinan or Al Quwayra fault zone. This was based on similarities of features on either side of the Araba Valley. In particular, the Timna and the Feinan copper mines, located north of the Themed and Dana faults, and the onlap of the Cambrian formations southward onto the Amram rhyolite and Ahyamir volcanics. To these we add a more accurate offset indicator in the form of an offset Early Cambrian (532 Ma) dolerite dyke previously mapped in Mount Amram (Israel) on the African plate and recently discovered across the Araba Valley in Jabal Sumr al Tayyiba (southwest Jordan) on the Arabian plate. This dolerite dyke is 20 m thick, strikes N50°E and is the only dyke intruding the Jabal Sumr al Tayyiba pink rhyolite flows of the Ahyamir Volcanics. Geochemical and geochronological correlations between the Jabal Sumr al Tayyiba dolerite dyke and the Mount Amram dolerite dyke demonstrate 85 km of sinistral offset across the Arava/Araba fault. Our results also suggest approximately 109 km of combined sinistral displacement across the Arava/Araba and Feinan faults based on petrological correlations between the Timna and Jabal Hanna igneous complexes on the African and Arabian plates, respectively. This constrains the total sinistral displacement of the Feinan fault and its accessory faults to be 24 km.

Small-Scale Spectral and Color Analysis of Ritchey Crater Impact Materials

NASA Astrophysics Data System (ADS)

Bray, Veronica; Chojnacki, Matthew; McEwen, Alfred; Heyd, Rodney

2014-11-01

Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) analysis of Ritchey crater on Mars has allowed identification of the minerals uplifted from depth within its central peak as well as the dominant spectral signature of the crater fill materials which surround it. However, the 18m/px resolution of CRISM prevents full analysis of the nature of small-scale dykes, mega breccia blocks and finer scale crater-fill units. We extend our existing CRISM-based compositional mapping of the Ritchey crater interior to sub-CRISM pixel scales with the use of High Resolution Imaging Science Experiment (HiRISE) Color Ratio Products (CRPs). These CRPs are then compared to CRISM images; correlation between color ratio and CRISM spectral signature for a large bedrock unit is defined and used to suggest similar composition for a smaller unit with the same color ratio. Megabreccia deposits, angular fragments of rock in excess of 1 meter in diameter within a finer grained matrix, are common at Ritchey. The dominant spectral signature from each megabreccia unit varies with location around Ritchey and appears to reflect the matrix composition (based on texture and albedo similarities to surrounding rocks) rather than clast composition. In cases where the breccia block size is large enough for CRISM analysis, many different mineral compositions are noted (low calcium pyroxene (LCP) olivine (OL), alteration products) depending on the location. All block compositions (as inferred from CRPs) are observed down to the limit of HiRISE resolution. We have found a variety of dyke compositions within our mapping area. Correlation between CRP color and CRISM spectra in this area suggest that large 10 m wide) dykes within LCP-bearing bedrock close to the crater center tend to have similar composition to the host rock. Smaller dykes running non-parallel to the larger dykes are inferred to be OL-rich suggesting multiple phases of dyke formation within the Ritchey crater and its bedrock.

Talking With Your Doctor - Multiple Languages

MedlinePlus

... this page, please enable JavaScript. Amharic (Amarɨñña / አማርኛ ) Arabic (العربية) Burmese (myanma bhasa) Chinese, Simplified (Mandarin dialect) ( ... Karen (S’gaw Karen) Kinyarwanda (Rwanda) Korean (한국어) Levantine (Arabic dialect) (الـلَّـهْـجَـةُ الـشَّـامِـيَّـة) Nepali (नेपाली) Pashto (Pax̌tō / ...

Stress - Multiple Languages

MedlinePlus

... this page, please enable JavaScript. Amharic (Amarɨñña / አማርኛ ) Arabic (العربية) Bosnian (bosanski) Burmese (myanma bhasa) Chinese, Simplified ( ... Karen (S’gaw Karen) Kinyarwanda (Rwanda) Korean (한국어) Levantine (Arabic dialect) (الـلَّـهْـجَـةُ الـشَّـامِـيَّـة) Nepali (नेपाली) Pashto (Pax̌tō / ...

High Blood Pressure - Multiple Languages

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Structural setting of Fimiston- and Oroya-style pyrite-telluride-gold lodes, Paringa South mine, Golden Mile, Kalgoorlie: 1. Shear zone systems, porphyry dykes and deposit-scale alteration zones

NASA Astrophysics Data System (ADS)

Mueller, Andreas G.

2017-07-01

The Golden Mile in the 2.7 Ga Eastern Goldfields Province of the Yilgarn Craton, Western Australia, has produced 385 million tonnes of ore at a head grade of 5.23 g/t gold (1893-2016). Gold-pyrite ore bodies (Fimiston Lodes) trace kilometre-scale shear zone systems centred on the D2 Golden Mile Fault, one of three northwest striking sinistral strike-slip faults segmenting upright D1 folds. The Fimiston shear zones formed as D2a Riedel systems in greenschist-facies (actinolite-albite) tholeiitic rocks, the 700-m-thick Golden Mile Dolerite (GMD) sill and the Paringa Basalt (PB), during left-lateral displacement of up to 12 km on the D2 master faults. Pre-mineralisation granodiorite dykes were emplaced into the D2 shear zones at 2674 ± 6 Ma, and syn-mineralisation diorite porphyries at 2663 ± 11 Ma. The widespread infiltration of hydrothermal fluid generated chlorite-calcite and muscovite-ankerite alteration in the Golden Mile, and paragonite-ankerite-chloritoid alteration southeast of the deposit. Fluid infiltration reactivated the D2 shear zones causing post-porphyry displacement of up to 30 m at principal Fimiston Lodes moving the southwest block down and southeast along lines pitching 20°SE. D3 reverse faulting at the southwest dipping GMD-PB contact of the D1 Kalgoorlie Anticline formed the 1.3-km-long Oroya Shoot during late gold-telluride mineralisation. Syn-mineralisation D3a reverse faulting alternated with periods of sinistral strike-slip (D2c) until ENE-WSW shortening prevailed and was accommodated by barren D3b thrusts. North-striking D4 strike-slip faults of up to 2 km dextral displacement crosscut the Fimiston Lodes and the barren thrusts, and control gold-pyrite quartz vein ore at Mt. Charlotte (2651 ± 9 Ma).

Genesee River Basin Study. Volume 1. Main Report.

DTIC Science & Technology

1988-06-01

Watersheds" by the U.S. Department of Agriculture, Soil Conservation Service, was prepared in June and October 1974. The report entitled "Dyke Creek...Watershed Preliminary Evaluation" by the U.S. Department of Agriculture, Soil Conservation Service, was prepared in December 1974. The report recommended... Soil Conservation Service prepared the draft report "Dyke Creek, P.L. 566 Watershed Project, Watershed Plan and Environmental Assessment" in June

Health Information in Levantine (Arabic dialect) (الـلَّـهْـجَـةُ الـشَّـامِـيَّـة)

MedlinePlus

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Poisoning - Multiple Languages

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Infection Control - Multiple Languages

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The effect of pre-tectonic reaction and annealing extent on behaviour during subsequent deformation: Insights from paired shear zones in the lower crust of Fiordland, New Zealand

NASA Astrophysics Data System (ADS)

Piazolo, Sandra; Daczko, Nathan R.; Smith, James R.; Evans, Lynn

2015-04-01

The effect of pre-tectonic reaction and annealing extent on the rheology of lower crustal rocks during a subsequent deformation event was studied using field and detailed microstructural analyses combined with numerical simulations to examine. In the studied rocks (Pembroke granulite, South Island, New Zealand) granulite facies two-pyroxene-pargasite orthogneiss partially to completely reacted to garnet bearing granulite either side of felsic dykes. The metamorphic reaction not only changed the abundance of phases but also their shape and grain size distribution. The reaction is most advanced close to the dykes, whereas further away the reaction is incomplete. As a consequence, grain size and the abundance of the rheologically hard phase garnet decreases away from the felsic dykes. Aspect ratios of mafic clusters which may include garnet decrease from high in the host, to near equidimensional close to the dyke. Post-reaction deformation localized in those areas that experienced minor to moderate reaction extent producing two spaced "paired" shear zones within the garnet-bearing reaction zone at either side of the felsic dykes. Our study shows how rock flow properties are governed by the pre-deformation history of a rock in terms of reaction and coupled annealing extent. If the grain size is sufficiently reduced by metamorphic reaction, deformation localizes in the partially finer grained rock domains, where deformation dominantly occurs by grain size sensitive deformation flow. Even if the reaction produces a nominally stronger phase (e.g. garnet) than the reactants, a local switch in dominant deformation behaviour from a grain size insensitive to a grain size sensitive in reaction induced fine-grained portions of the rock may occur and result in significant strain localization.

Postmagmatic magnetite-apatite assemblage in mafic intrusions: a case study of dolerite at Olympic Dam, South Australia

NASA Astrophysics Data System (ADS)

Apukhtina, Olga B.; Kamenetsky, Vadim S.; Ehrig, Kathy; Kamenetsky, Maya B.; McPhie, Jocelyn; Maas, Roland; Meffre, Sebastien; Goemann, Karsten; Rodemann, Thomas; Cook, Nigel J.; Ciobanu, Cristiana L.

2016-01-01

An assemblage of magnetite and apatite is common worldwide in different ore deposit types, including disparate members of the iron-oxide copper-gold (IOCG) clan. The Kiruna-type iron oxide-apatite deposits, a subtype of the IOCG family, are recognized as economic targets as well. A wide range of competing genetic models exists for magnetite-apatite deposits, including magmatic, magmatic-hydrothermal, hydrothermal(-metasomatic), and sedimentary(-exhalative). The sources and mechanisms of transport and deposition of Fe and P remain highly debatable. This study reports petrographic and geochemical features of the magnetite-apatite-rich vein assemblages in the dolerite dykes of the Gairdner Dyke Swarm (~0.82 Ga) that intruded the Roxby Downs Granite (~0.59 Ga), the host of the supergiant Olympic Dam IOCG deposit. These symmetrical, only few mm narrow veins are prevalent in such dykes and comprise besides usually colloform magnetite and prismatic apatite also further minerals (e.g., calcite, quartz). The genetic relationships between the veins and host dolerite are implied based on alteration in the immediate vicinity (~4 mm) of the veins. In particular, Ti-magnetite-ilmenite is partially to completely transformed to titanite and magmatic apatite disappears. We conclude that the mafic dykes were a local source of Fe and P re-concentrated in the magnetite-apatite veins. Uranium-Pb ages for vein apatite and titanite associated with the vein in this case study suggest that alteration of the dolerite and healing of the fractures occurred shortly after dyke emplacement. We propose that in this particular case the origin of the magnetite-apatite assemblage is clearly related to hydrothermal alteration of the host mafic magmatic rocks.

Magmatic history of Red Sea rifting: perspective from the central Saudi Arabian coastal plain.

USGS Publications Warehouse

Pallister, J.S.

1987-01-01

An early stage of magmatism related to Red Sea rifting is recorded by a Tertiary dyke complex and comagmatic volcanic rocks exposed on the central Saudi Arabian coastal plain. Field relations and new K/Ar dates indicate episodic magmatism from approx 30 m.y. to the present day and rift-related magmatism as early as 50 m.y. Localized volcanism and sheeted dyke injection ceased at approx 20 m.y. and were replaced by the intrusion of thick gabbro dykes, marking the onset of sea-floor spreading in the central Red Sea. Differences in the depths and dynamics of mantle-melt extraction and transport may account for the transition from mixed alkaline-subalkaline bimodal magmatism of the pre-20 m.y. rift basin to exclusively subalkaline (tholeiitic) magmatism of the Red Sea spreading axis and the alkali basalt volcanism inland.-L.C.H.

A high repetition rate transverse beam profile diagnostic for laser-plasma proton sources

NASA Astrophysics Data System (ADS)

Dover, Nicholas; Nishiuchi, Mamiko; Sakaki, Hironao; Kando, Masaki; Nishitani, Keita

2016-10-01

The recently upgraded J-KAREN-P laser can provide PW peak power and intensities approaching 1022 Wcm-2 at 0.1 Hz. Scaling of sheath acceleration to such high intensities predicts generation of protons to near 100 MeV, but changes in electron heating mechanisms may affect the emitted proton beam properties, such as divergence and pointing. High repetition rate simultaneous measurement of the transverse proton distribution and energy spectrum are therefore key to understanding and optimising the source. Recently plastic scintillators have been used to measure online proton beam transverse profiles, removing the need for time consuming post-processing. We are therefore developing a scintillator based transverse proton beam profile diagnostic for use in ion acceleration experiments using the J-KAREN-P laser. Differential filtering provides a coarse energy spectrum measurement, and time-gating allows differentiation of protons from other radiation. We will discuss the design and implementation of the diagnostic, as well as proof-of-principle results from initial experiments on the J-KAREN-P system demonstrating the measurement of sheath accelerated proton beams up to 20 MeV.

An observation of sea-spray microphysics by airborne Doppler radar

NASA Astrophysics Data System (ADS)

Fairall, C. W.; Pezoa, S.; Moran, K.; Wolfe, D.

2014-05-01

This paper describes observations and analysis of Doppler radar data from a down-looking 94 GHz (W-Band) system operated from a NOAA WP-3 Orion research aircraft in Tropical Storm (TS) Karen. The flight took place on 5 October 2013; Karen had weakened with maximum winds around 20 m s-1. Doppler spectral moments from the radar were processed to retrieve sea-spray microphysical properties (drop size and liquid water mass concentration) profiles in the height range 75-300 m above the sea surface. In the high wind speed regions of TS Karen (U10 > 15 m s-1), sea spray was observed with a nominal mass-mode radius of about 40 µm, a radar-weighted gravitational fall velocity of about 1 m s-1, and a mass concentration of about 10-3 gm-3 at 75 m. Spray-drop mass concentration declined with height to values of about 10-4 gm-3 at 300 m. Drop mass decreased slightly more slowly with increasing height than predicted by surface-layer similarity theory for a balance of turbulent diffusion vs fall velocity.

High-precision mapping of seismicity in the 2014 Bárdarbunga volcanic episode

NASA Astrophysics Data System (ADS)

Vogfjörd, Kristín S.; Hensch, Martin; Gudmundsson, Gunnar B.; Jónsdóttir, Kristín

2015-04-01

The Bárdarbunga volcano and its associated fissure swarm in Iceland's Eastern volcanic zone is a highly active system with over 20 eruptions in the last 11 centuries. The location of this active volcano and much of the fissure swarm under several hundred metres thick ice gives rise to multiple hazards, including explosive, subglacial eruptions and associated subglacial floods (jökulhlaups), as well as fissure eruptions extruding large volumes of lava. After a decade of increasing seismic activity, volcanic unrest at Bárdarbunga suddenly escalated into a minor subglacial eruption on 16 August 2014. In the following weeks seismic activity soared and surface deformation of tens of cm were observed, caused by rifting and a dyke intrusion, which propagated 48 km northward from the central volcano (Sigmundsson et al., 2014). The dyke propagation stopped just outside the glacial margin and ended in a fissure eruption at Holuhraun at the end of August. At the time of writing the eruption is ongoing, having extruded a lava volume of over 1 km3 and released high rates of SO2 into the atmosphere. Over twenty thousand microearthquakes have been recorded. Initially most were in the dyke, but after the first two weeks the activity around the caldera rim increased and over 70 shallow earthquakes with MW > 5 have been located along the caldera rim accompanied by caldera subsidence. At the onset of the unrest on 16 August, the seismicity was located in the caldera and north of the caldera rim, but already in the first few hours the activity propagated out of the caldera to the SE. Still, the activity continued for a few days in the fissure swarm to the NE of the rim. High-precision earthquake locations in the propagating dyke have revealed its very detailed, planar rifting segments, with the events distributed over a 3-4 km depth range, and mostly between 6 and 9 km. These very planar event distributions are highly unusual in volcanic areas and strongly suggest rifting of

Evolution of the magma feeding system during a Plinian eruption: The case of Pomici di Avellino eruption of Somma-Vesuvius, Italy

NASA Astrophysics Data System (ADS)

Massaro, S.; Costa, A.; Sulpizio, R.

2018-01-01

The current paradigm for volcanic eruptions is that magma erupts from a deep magma reservoir through a volcanic conduit, typically modelled with fixed rigid geometries such as cylinders. This simplistic view of a volcanic eruption does not account for the complex dynamics that usually characterise a large explosive event. Numerical simulations of magma flow in a conduit combined with volcanological and geological data, allow for the first description of a physics-based model of the feeding system evolution during a sustained phase of an explosive eruption. The method was applied to the Plinian phase of the Pomici di Avellino eruption (PdA, 3945 ±10 cal yr BP) from Somma-Vesuvius (Italy). Information available from volcanology, petrology, and lithology studies was used as input data and as constraints for the model. In particular, Mass Discharge Rates (MDRs) assessed from volcanological methods were used as target values for numerical simulations. The model solutions, which are non-unique, were constrained using geological and volcanological data, such as volume estimates and types of lithic components in the fall deposits. Three stable geometric configurations of the feeding system (described assuming elliptical cross-section of variable dimensions) were assessed for the Eruptive Units 2 and 3 (EU2, EU3), which form the magmatic Plinian phase of PdA eruption. They describe the conduit system geometry at time of deposition of EU2 base, EU2 top, and EU3. A 7-km deep dyke (length 2 a = 200-4 00 m, width 2 b = 10- 12 m), connecting the magma chamber to the surface, characterised the feeding system at the onset of the Plinian phase (EU2 base). The feeding system rapidly evolved into hybrid geometric configuration, with a deeper dyke (length 2 a = 600- 800 m, width 2 b = 50 m) and a shallower cylindrical conduit (diameter D = 50 m, dyke-to-cylinder transition depth ∼2100 m), during the eruption of the EU2 top. The deeper dyke reached the dimensions of 2 a = 2000 m and

Comparative use of TIMS and SHRIMP for U Pb zircon dating of A-type granites and mafic tholeiitic layered complexes and dykes from the Corsican Batholith (France)

NASA Astrophysics Data System (ADS)

Cocherie, A.; Rossi, Ph.; Fanning, C. M.; Guerrot, C.

2005-05-01

The Corsica-Sardinia batholith in the southern realm of the Hercynian belt of Europe shows evidence for gravitational collapse of this part of the mountain belt, causing major felsic and mafic magmatism. The latest intrusions are composed of leucomonzogranite and late metaluminous and alkaline granite, associated with tholeiitic layered complexes and dykes. Three dating methods on zircon (Pb-evaporation, ID-TIMS and SHRIMP) were used to unravel the chronology of these felsic and mafic rocks. Dating of zircons by the conventional U-Pb method, using TIMS after zircon dissolution, achieved an analytical uncertainty of 1 Ma for favourable cases. The TIMS Pb-evaporation technique resulted in ages with an uncertainty range of 4 to 8 Ma. After 15 to 20 analyses with the SHRIMP method, a precision ranging from 2 to 5 Ma was obtained (all at 2 σ). The three methods applied to the same zircon population extracted from four A-type granites, show that the uncertainty ranges within 2-5 Ma according to the sample. This error seems to correspond to the real geochronological uncertainty that can be achieved. The results obtained show that all six tested alkaline granites were emplaced during a very short interval of about 3-5 Ma at about 288 Ma, almost contemporaneous with the leucomonzogranite emplacement (291-287 Ma) that ended the batholith formation. In addition, there is no significant gap with the age of emplacement of the mafic tholeiitic magmatism (around 286 Ma) crosscutting the "A-type" granites. The late alkaline granites definitely do not show up here as precursors of the Tethyan rifting that began at about 170 Ma, i.e. some 100 Ma after their emplacement. It is thus necessary to examine if alternative hypotheses to the anorogenic model of the A-type Younger Granite province better fit the new geochronological data. A model involving depleted continental-crust derived magma should be compatible with the timing and geodynamical constraints as far as isotopic data are

Expedition 36 State Commission

NASA Image and Video Library

2013-05-27

Expedition 36/37 Soyuz Commander Fyodor Yurchikhin of the Russian Federal Space Agency (Roscosmos) holds up posters of his crew during the State Commission meeting at the Cosmonaut Hotel as Expedition 36 Flight Engineer Karen Nyberg of NASA looks on, Monday, May 27, 2013, in Kazakhstan. Yurichikin and his fellow crew members, Flight Engineers; Karen Nyberg of NASA, and Luca Parmitano of the European Space Agency, were in quarantine and kept behind glass during the meeting in preparation for their launch on a Soyuz rocket to the International Space Station (ISS) on Wednesday May 29, Kazakh time. Photo credit: (NASA/Bill Ingalls)

Systems Dynamics Modelling Identifies (Un)Sustainable Rice Cultivation Strategies for the Mekong Delta Under Upstream Hydropower Development

NASA Astrophysics Data System (ADS)

Darby, S. E.; Chapman, A.; Hackney, C. R.; Leyland, J.; Parsons, D. R.; Aalto, R. E.; Nicholas, A. P.; Best, J.

2016-12-01

The Vietnamese Mekong delta is one of the world's largest rice producing regions, but it is facing a major sustainability challenge. The delta is being `drowned' by rising relative sea-levels, a situation that is being exacerbated by a reduction in the supply of rivers sediments due to a combination of climate change and sediment trapping linked to the construction of large hydropower dams in upstream countries. Poverty is prevalent and farmers face many challenges, such as declining productivity, income insecurity and debt; they are therefore reliant on natural ecosystem services, notably soil nutrient replenishment by sediment deposition during floods, to minimise dependence on chemical fertilisers. Meanwhile, the drive to intensify rice production (a key national policy goal that has underpinned the region's recent economic development) has been achieved by replacing the traditional use of `low' (0-2m in height) dyke networks with `high' (>3.5m) dyke networks. Since rice production takes place within these dyke rings, this has enabled a switch from traditional cultivation techniques (double cropping within low dyke rings) to a new system of triple cropping (in which an extra crop can be grown due to the exclusion of flood waters during the monsoon season) within the high dykes. This involves trading off immediate benefits (protection against floods; improved rice production) against long term disadvantages (the exclusion of sediment accelerates relative sea-level rise, adding to flood risk in the long term, while sediment borne nutrients are key to agricultural productivity in the long term). Here we use systems dynamics modelling to demonstrate that current rice cultivation strategies are a maladaptation which, under a future of declining sediment loads due to upstream hydropower development, are not sustainable in the long term and present recommendations for more sustainable water management policies in the delta's rice growing region.

Obituary: Lynne Karen Deutsch, 1954-2004

NASA Astrophysics Data System (ADS)

Sprague, Ann L.

2004-12-01

It is with deep sadness and regret that we note the passing of our dear friend and colleague Prof. Lynne K. Deutsch. Lynne died on 2 April 2004 after a protracted illness and lengthy battle with complications caused by the blood disease Polycythaemia Vera. Lynne was born in Chicago on 26 November 1956 to Victor and Ailsa Deutsch. She lived with her family in the town of Morton Grove, IL until she was 8 years old, when they moved to Beverly Hills, CA. She was an outgoing child who played basketball and excelled in her studies. She graduated from Beverly Hills High School at the age of 16 after completing all high school requirements in only three years. Lynne had a beautiful singing voice, and was in the chorus in high school and college. Lynne earned her first bachelor's degree in philosophy from the University of California at Berkeley in 1977. She then returned to Berkeley and received a second bachelor's degree, this time in physics, in 1981. She was a graduate student and teaching assistant at MIT and earned an MS in physics from MIT in 1983. Lynne then attended the astronomy graduate program at Harvard University, where she earned her MA in 1985 and PhD in 1990. During her degree studies she began crafting mid-infrared instrumentation. These instruments were destined to be used by a host of eager observers to discover, identify, and study many emissions from the Solar System, and galactic and extragalactic sources. Lynne was a National Research Council Post-doctoral Fellow at NASA Ames Research Center from 1990 - 1992, where she played an important role in the development of the Smithsonian Astrophysical Observatory/University of Arizona Mid-Infrared Array Camera (MIRAC), a well-known and much sought after instrument frequently used in studies of Mercury, Jupiter, the Moon, planetary nebulae, star formation regions, galactic center, young stellar objects, and extragalactic objects. After leaving NASA Ames Research Center, Lynne taught for several years (1993-96) at Smith College where she had a significant impact on undergraduate research, especially for women, whom she enjoyed mentoring. Lynne joined the faculty in the Astronomy Department of Boston University in 1996 where she taught instrumentation principles and techniques to undergraduate and graduate students. Over the course of her faculty career, she received numerous research grants and fellowships that were used to support her research, her students, and her postdoctoral associates. She was the principal investigator of Boston University's advanced technologies and instrumentation program MIRABU: A Mid-Infrared Array. As her health declined and the rigors of a full teaching schedule became unacceptably taxing, Lynne took a leave of absence from Boston University and returned to Harvard University and the Center for Astrophysics in 2001. There she became a very active member of the Infrared Group in the OIR Division and a member of the IRAC/Spitzer Space Telescope team. Her research in infrared astronomy covered many areas including star formation, planetary and protoplanetary nebulae, solar system objects, the interstellar medium and infrared-luminous galaxies. Her most recent research with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope concentrated on high-mass star formation and the related evolution of the interstellar medium. In her short life, Lynne made many devoted friends and colleagues and was active in encouraging school-age girls to pursue their interests in the sciences. In her short career, she published more than seventy-five articles. She was an outstanding observer and instrumentalist, whose promising career was tragically cut short. Lynne was also a devoted mother and wife, and, while still well, she found the time to be an active participant in her son's elementary school. She is very greatly missed by her family. She is survived by her husband Douglas Sondak, PhD and her son Reed Deutsch-Sondak who live in Acton, MA, and her parents and sister Judith who reside in California. Lynne will be forever missed by her family, friends, colleagues, and the astronomical community. Her contributions will continue to benefit the community for many years to come. We only wish she were here to share them with us. She will be remembered as a dear friend, colleague, accomplished scientist, and dedicated family member.

High initiation and long duration of breastfeeding despite absence of early skin-to-skin contact in Karen refugees on the Thai-Myanmar border: a mixed methods study

PubMed Central

2012-01-01

Background Early skin-to-skin contact (SSC) after birth is recommended as part of the United Nations Children’s Fund (UNICEF) baby friendly health initiative to promote optimum breastfeeding. This paper reports rates of breastfeeding initiation and duration in a low resource environment, where early SSC is not practised, and explores views of pregnant women and midwives surrounding breastfeeding and swaddling. Methods Data from records from a single hospital on the Thai-Myanmar border where refugee women gave birth during a one-year period (2010) were used to determine breastfeeding initiation rates and the time of the first breastfeed, and duration of breastfeeding of the previous alive child in multigravidae. Focus group discussions (FGD) were conducted to obtain information from pregnant women attending antenatal care about their intended or previous duration of breastfeeding and views on breastfeeding. Interviews with local midwives explored reasons for high rates of breastfeeding in this setting and the practice of newborn swaddling. Results Of 1404 live births in 2010 in Maela refugee camp there were 982 evaluable mother-newborn pairs, including 80 infants born before 37 weeks gestation. Initiation of breastfeeding within the first hour after birth and exclusive breastfeeding at discharge in term mother-newborn pairs was 91.2% (823/902) and 99.3% (896/902); and before 37 weeks gestation, 48.8% (39/80) and 98.8% (79/80). Reported duration of previous breastfeeding was 19 (range 2 to 72) months. During FGD all primigravidae (n = 17) intended to breastfeed and all multigravidae (n = 33) had previously breastfed; expected or previous duration of feeding was for more than one year or longer. The major theme identified during FGD was breastfeeding is “good”. Women stated their intention to breastfeed with certainty. This certainty was echoed during the interviews with midwifery staff. SSC requires a delay in early swaddling that in Karen people, with

Anisotropy of magnetic susceptibility (AMS) in the Siilinjärvi carbonatite complex, eastern Finland

NASA Astrophysics Data System (ADS)

Almqvist, Bjarne; Karell, Fredrik; Högdahl, Karin; Malehmir, Alireza; Heino, Pasi; Salo, Aleksi

2017-04-01

We present a set of AMS measurements on samples from the Siilinjärvi alkaline-carbonatite complex in eastern Finland. The complex has a tabular shape (ca. 16 km long, 1.5 km wide) that strikes north-south and is constrained within a steeply dipping N-S oriented deformation zone. It consists of a mixture of lithologies, including carbonatite, fenite and glimmerite (mica-rich rocks), which is hosted within a Precambrian granite and gneiss. After emplacement of the carbonatite, the complex was subsequently intruded by diabase dykes. Deformation has occurred in several episodes after dyke intrusions, and strain is heterogeneously distributed among the different lithologies. Strain localizes mainly within glimmerite and carbonatite, and at the contacts between dykes and glimmerite/carbonatite where shear zones develop locally. Structures provide indications for both simple (strike-slip) and pure shear components in the deformation history of the complex, although the former may dominate. Thirty-six localities were sampled, providing 272 specimens for AMS measurements, within the southern and eastern parts of the Siilinjärvi open-pit mine (within the complex), mainly from diabase dykes, glimmerite and carbonatites; a smaller number of samples were collected from fenite. Sampling was carried out in order to investigate magnetic fabrics in relation to the emplacement of the dykes and their structural relationship to the glimmerite/carbonatite. Structural measurements were made to accompany the magnetic fabric study. The magnetic fabric shows a magnetic foliation plane that is oriented north-south, with sub-horizontal k3-axes oriented nearly east-west. Magnetic lineation (k1) clusters sub-vertically, but does show a tendency to spread along the north-south magnetic foliation great circle. The dataset can be further divided into two sub-sets based on the bulk susceptibility (km) and degree of anisotropy (P). The bulk of the data set ( 70 %), belonging to samples of diabase

Dynamics of Rifting in two Active Rift Segments in Afar - Geodetic and Structural Studies - DoRA Project

NASA Astrophysics Data System (ADS)

Doubre, C.; Socquet, A.; Masson, F.; Jacques, E.; Grandin, R.; Nercessian, A.; Kassim, M.; Vergne, J.; Diament, M.; Hinderer, J.; Ayele, A.; Lewi, E.; Calais, E.; Peltzer, G.; Toussaint, R.; de Chaballier, J.; Ballu, V. S.; Luck, B.; King, G. C.; Vigny, C.; Cattin, R.; Tiberi, C.; Kidane, T.; Jalludin, M.; Maggi, A.; Dorbath, C.; Manatschal, G.; Schmittbuhl, J.; Le Moigne, N.; Deroussi, S.

2009-12-01

The DoRA project aims to conduct complementary studies in two volcano-tectonic rifts in the Afar Depression. In Northern Afar, the Wal’is Dabbahu Rift (WD, Ethiopia) is currently undergoing a major rifting episode. This event started in September 2005 with a significant seismic activity. InSAR data revealed the injection of a 65 km-long mega-dyke that opened by up to 8 m, the slip of numerous normal faults and opening of fissures, and a rhyolitic eruption. Similarly, the Asal-Ghoubbet Rift (AG, Djibouti) was affected in 1978 by a smaller episode of rifting associated with the intrusion of a 2 m wide dyke into the crust. Since then, a large catalog of geodetic data that includes recent InSAR time series reveals the importance of non-steady deformation controlling the rift dynamics. Our goal is to gain an understanding of such volcano-tectonic segments on several time scales, including the dyking period itself and the post-event period. The study of the behavior of the AG Rift during its whole post-rifting period offers an image at t+30 years of the WD segment, while keeping in mind important structural and scale differences. First, we propose to build a complete and accurate set of geodetic data (InSAR, cGPS, GPS), covering the period under study. With a narrow temporal sample window, we will precisely describe the aseismic slip affecting the normal faults of these rifts, the periods of sudden slip and/or slip acceleration but also measure the deformation associated with probable future dyke intrusion. Second, we aim to constrain the origin of these displacements and their relation with mass transfers within the crust. Series of gravity measurements will be pursue or initiated in both rifts. Third, the recording of seismic activity is essential to constrain the relative importance of seismic and aseismic deformation. This will also help to evaluate the thickness of the seismogenic layer. Together with structural data collected during a seismic survey in the AG

Volcano-tectonics of the Al Haruj Volcanic Province, Central Libya

NASA Astrophysics Data System (ADS)

Elshaafi, Abdelsalam; Gudmundsson, Agust

2016-10-01

The Al Haruj intra-continental Volcanic Province (AHVP), located at the south-western margin of the Sirt Basin, hosts the most extensive and recent volcanic activity in Libya - which is considered typical for plate interiors. From north to south the AHVP is divided into two subprovinces, namely Al Haruj al Aswad and Al Haruj al Abiyad. The total area of the AHVP is around 42,000 km2. Despite the great size of the AHVP, its volcano-tectonic evolution and activity have received very little attention and are poorly documented and understood. Here we present new field data, and analytical and numerical results, on the volcano-tectonics of the AHVP. The length/thickness ratio of 47 dykes and volcanic fissures were measured to estimate magmatic overpressure at the time of eruption. The average dyke (length/thickness) ratio of 421 indicates magmatic overpressures during the associate fissure eruptions of 8-19 MPa (depending on host-rock elastic properties). Spatial distributions of 432 monogenetic eruptions sites/points (lava shields, pyroclastic cones) in the AHVP reveal two main clusters, one in the south and another in the north. Aligned eruptive vents show the dominating strike of volcanic fissures/feeder-dykes as WNW-ESE to NW-SE, coinciding with the orientation of one of main fracture/fault zones. Numerical modelling and field observations suggest that some feeder-dykes may have used steeply dipping normal-fault zones as part of their paths to the surface.

A mechanism for decoupling within the oceanic lithosphere revealed in the Troodos ophiolite

USGS Publications Warehouse

Agar, Susan M.; Klitgord, Kim D.

1995-01-01

Contrasting kinematic histories recorded in the sheeted dykes and underlying plutonic rocks of the Troodos ophiolite provide a new perspective on the mechanical evolution of oceanic spreading centres. The kinematic framework of the decoupling zone that partitions deformation between the sheeted dykes and plutonics contrasts with low-angle detachment models for slow-spreading ridges based on continental-rift analogues. A model for the generation of multiple, horizontal decoupling horizons, linked by planar normal faults, demonstrates new possibilities for the kinematic and rheological significance of seismic reflectors in oceanic lithosphere.

The 2009 and 2010 eruptions and shallow intrusions at Piton de la Fournaise, La Réunion Island, seen by cGPS measurements

NASA Astrophysics Data System (ADS)

Staudacher, Thomas; Peltier, Aline; Boissier, Patrice; di Muro, Andrea

2010-05-01

The Piton de la Fournaise volcano at La Réunion Island in the western Indian Ocean is one of the most active volcanoes in the world. Its average eruption rate over the last 2 centuries is one eruption every 9 months. Between 1998 and 2010 thirty eruptions occurred and produced some 300×106 m3 of lava flows. Since the 2007 collapse of 340 m of the Dolomieu caldera, the eruptive activity of the volcano changed with mainly the occurrence of numerous shallow intrusions preceding days or weeks small summit eruptions. In 2009-2010, Piton de la Fournaise erupted successively in November 5, December 14, 2009 and in January 2, 2010. The one day lasting November and December 2009 eruptions started from en echelon fissures close to the summit around its eastern and southern rims, respectively, whereas the January 2010 eruptive fissure opened on the western flank inside of the Dolomieu crater. These three eruptions produced less than 106 m3 of lava, but generated large ground deformation, of up to 70 cm, recorded by the cGPS network of the volcano observatory and by cinematic GPS measurements. The long term survey showed a small extent of the ground deformation field and the small ratios of base/summit displacements and vertical/horizontal displacements reveal the involvement of shallow dykes to fed these successive eruptions. The cGPS network allowed us to follow up precisely the pre eruptive ground deformations, the 40 to 90 minutes dyke propagation toward the surface, as well as the ground deformations after the vent opening. For the November and December 2009 eruptions, the dyke started below the western part of the Dolomieu crater, before propagating to the east and the south, respectively. For the January eruption, the dyke propagated along a more or less vertical pathway directly to the western part of the Dolomieu crater. The two previous dyke injections of November and December had increased the horizontal compressive stress of the eastern side of the Dolomieu

The dynamics of magma ascent in the crust: Characterising fluid flow and host-rock deformation using scaled analogue experiments

NASA Astrophysics Data System (ADS)

Kavanagh, Janine; Dennis, David

2015-04-01

We present the results from a series of analogue experiments that use gelatine injected by water to study magma ascent dynamics in the crust. Gelatine is a viscoelastic material that displays predominantly elastic deformation when used at low temperatures (5-10 °C) and mid-to-low concentrations (2-5 wt%). To study dyke propagation we have used a combination of Particle Image Velocimentry (PIV) and Digital Image Correlation (DIC) to characterise the dynamics of fluid flow within the intrusion and contemporaneous deformation of the host gelatine. Experiments are prepared by filling a 40 cm x 40 cm x 30 cm clear-Perspex tank with a gelatine mixture that has been seeded with neutrally buoyant fluorescent particles. Water, also seeded with tracer particles, is then injected into the solid gelatine from below under a constant flux or constant head pressure. This causes a vertical penny-shaped crack (dyke) to propagate through the gelatine and erupt at the surface. During the experiment, a vertical high-power laser sheet positioned along the centre of the tank is triggered to illuminate the seeding particles with short intense pulses, and two Dantec CCD cameras record successive images. Using PIV and DIC, vector fields of fluid flow within the intrusion and strain within the gelatine host is calculated by cross-correlation between successive images at a defined time interval. The experiments indicate that, prior to eruption, dyke propagation is characterised by rapid centralised and upwards fluid flow with accompanying downwards motion at the intrusion margin. Deformation of the gelatine solid is focused at a small head region, with the tail remaining relatively static as the dyke grows. Upon eruption, rapid centralised fluid evacuation occurs with contemporaneous contraction of the dyke and relaxation of the host gelatine. Models that can couple fluid dynamics and host deformation during magma ascent and eruption will make an important step towards improving our

Numerical simulation of magma chamber dynamics.

NASA Astrophysics Data System (ADS)

Longo, Antonella; Papale, Paolo; Montagna, Chiara Paola; Vassalli, Melissa; Giudice, Salvatore; Cassioli, Andrea

2010-05-01

Magma chambers are characterized by periodic arrivals of deep magma batches that give origin to complex patterns of magma convection and mixing, and modify the distribution of physical quantities inside the chamber. We simulate the transient, 2D, multi-component homogeneous dynamics in geometrically complex dyke+chamber systems, by means of GALES, a finite element parallel C++ code solving mass, momentum and energy equations for multi-component homogeneous gas-liquid (± crystals) mixtures in compressible-to-incompressible flow conditions. Code validation analysis includes several cases from the classical engineering literature, corresponding to a variety of subsonic to supersonic gas-liquid flow regimes (see http://www.pi.ingv.it/~longo/gales/gales.html). The model allows specification of the composition of the different magmas in the domain, in terms of ten major oxides plus the two volatile species H2O and CO2. Gas-liquid thermodynamics are modeled by using the compositional dependent, non-ideal model in Papale et al. (Chem.. Geol., 2006). Magma properties are defined in terms of local pressure, temperature, and composition including volatiles. Several applications are performed within domains characterized by the presence of one or more magma chambers and one or more dykes, with different geometries and characteristic size from hundreds of m to several km. In most simulations an initial compositional interface is placed at the top of a feeding dyke, or at larger depth, with the deeper magma having a lower density as a consequence of larger volatile content. The numerical results show complex patterns of magma refilling in the chamber, with alternating phases of magma ingression and magma sinking from the chamber into the feeding dyke. Intense mixing takes place in feeding dykes, so that the new magma entering the chamber is always a mixture of the deep and the initially resident magma. Buoyant plume rise occurs through the formation of complex convective

Concentrates and mantle xenocrysts from the Lao river Guinea and reconstructions of the mantle structure

NASA Astrophysics Data System (ADS)

Afanasiev, Valentin; Ashchepkov, Igor; Nikolenko, Eeugeny

2015-04-01

The discovery of the kimberlite dykes in Quinea in the basin of the Lao river means finding of the new diamondiferous kimberlite field in the West Africa. It is locating 100 km SW from Bubudu and contains large dykes and placers in Lao river. The kimberlite concentrate and diamondiferous placers are containing pyropes, chromites, Ilmenites and Cr diosides and low Cr- pyroxenes. Two river placers in Lao and Bobeko and newly discovered dyke slightly differ in compositions of minerals. mainly in representatives of the minerals though their compositional trends are in general similar. The concentrates from and Druzhba pipe (Bunudu) contains mainly ilmenite and more are pyropes. Garnets from all localities are close and belong mainly to the lherzolite field to 10 wt%Cr2O3. But the dyke contains essential amount of harzburgitic garnets starting from 2 %wt Cr2O3 and they became prevailing from 6 wt %Cr2O3. There are also megacrystic low - Cr pyropes in dyke concentrate. Dyke is rich in peridotites and coarse grained garnet pyroxenite xenoliths which are ranging from the low Cr -to Cr -diopside type Chromites from Dyke are Ti - low but are often Al rich. While chromites from Bobeko and especially Lao placers define the Cr- rich trend from 60 to 40 wt%Cr2O3 and demonstrate the deviation to ulvospinel trends with increasing of Al2O3 . Cr - Diopsides clinopyroxenites trace the Fe- Ti-Na-Al enrichment trend. Ilmenites from three localities - define close trends splitting to the two intervals 60-40 wt% TiO2 and 33-27 TiO2 which are enriched in Cr2O3 to 5wt% reflecting the crystallization of megacrystalline association at the lithosphere base and Ilm metasomatic vein stockwark near the Moho in pre-eruption feeding system. The Dyke ilmenites are Mg rich and mainly are captured from the deep part of the mantle section. Babeko and Druzhba localities are similar variations of ilmenite trends. Some ilmenites from Lao and Druzhba are Mn - rich and are less in Cr possibly reflecting

Control of Anion in Corporation in the Molecular Beam Epitaxy of Ternary Antimonide Superlattices for Very Long Wavelength Infrared Detection (Postprint)

DTIC Science & Technology

2015-10-01

ASSIGNED DISTRIBUTION STATEMENT. //Signature// //Signature// GAIL J. BROWN DIANA M. CARLIN, Chief Nanoelectronic ...Materials Branch Nanoelectronic Materials Branch Functional Materials Division Functional Materials Division //Signature// KAREN

"What About the Next Generation That's Coming?": The Recontextualization of Mothering Post-Refugee Resettlement.

PubMed

Hoffman, Sarah J; Robertson, Cheryl L; Tierney, Jessica Dockter

The purpose of this analysis was to explore the recontextualization of mothering in Karen refugees from Burma. We collected ethnographic data over an 11-month period with a cohort of 12 Karen women postresettlement. Using Spradley's and tools of critical discourse analysis, we interpreted the migration narratives of women, in particular, experiences they shared as mothers. These narratives were grounded in the space of cultural difference; thus, we engaged hybridity as a theoretical frame. Findings reflect the negotiation of mothering practices within the norms, structures, and policies of the country of resettlement. We identified the spaces of transformation a woman constructed to usher change while sustaining a connection between herself, her culture, and her children.

Rates and probable causes of freshwater tidal marsh failure, Potomac River Estuary, Northern Virginia, USA

USGS Publications Warehouse

Litwin, Ronald J.; Smoot, Joseph P.; Pavich, Milan J.; Markewich, Helaine Walsh; Oberg, Erik T.; Steury, Brent W.; Helwig, Ben; Santucci, Vincent L.; Sanders, Geoffrey

2013-01-01

Dyke Marsh, a distal tidal marsh along the Potomac River estuary, is diminishing rapidly in areal extent. This study documents Dyke Marsh erosion rates from the early-1860s to the present during pre-mining, mining, and post-mining phases. From the late-1930s to the mid-1970s, Dyke Marsh and the adjacent shallow riverbottom were mined for gravel, resulting in a ~55 % initial loss of area. Marsh loss continued during the post-mining phase (1976–2012). Causes of post-mining loss were unknown, but were thought to include Potomac River flooding. Post-mining areal-erosion rates increased from 0.138 ha yr−1 (~0.37 ac yr−1) to 0.516 ha yr−1(~1.67 ac yr−1), and shoreline-erosion rates increased from 0.76 m yr−1 (~2.5 ft yr−1) to 2.60 m yr−1 (~8.5 ft yr−1). Results suggest the accelerating post-mining erosion reflects a process-driven feedback loop, enabled by the marsh's severely-altered geomorphic and hydrologic baseline system; the primary post-mining degradation process is wave-induced erosion from northbound cyclonic storms. Dyke Marsh erosion rates are now comparable to, or exceed, rates for proximal coastal marshes in the same region. Persistent and accelerated erosion of marshland long after cessation of mining illustrates the long-term, and potentially devastating, effects that temporally-restricted, anthropogenic destabilization can have on estuarine marsh systems.

2D and 3D separate and joint inversion of airborne ZTEM and ground AMT data: Synthetic model studies

NASA Astrophysics Data System (ADS)

Sasaki, Yutaka; Yi, Myeong-Jong; Choi, Jihyang

2014-05-01

The ZTEM (Z-axis Tipper Electromagnetic) method measures naturally occurring audio-frequency magnetic fields and obtains the tipper function that defines the relationship among the three components of the magnetic field. Since the anomalous tipper responses are caused by the presence of lateral resistivity variations, the ZTEM survey is most suited for detecting and delineating conductive bodies extending to considerable depths, such as graphitic dykes encountered in the exploration of unconformity type uranium deposit. Our simulations shows that inversion of ZTEM data can detect reasonably well multiple conductive dykes placed 1 km apart. One important issue regarding ZTEM inversion is the effect of the initial model, because homogeneous half-space and (1D) layered structures produce no responses. For the 2D model with multiple conductive dykes, the inversion results were useful for locating the dykes even when the initial model was not close to the true background resistivity. For general 3D structures, however, the resolution of the conductive bodies can be reduced considerably depending on the initial model. This is because the tipper magnitudes from 3D conductors are smaller due to boundary charges than the 2D responses. To alleviate this disadvantage of ZTEM surveys, we combined ZTEM and audio-frequency magnetotelluric (AMT) data. Inversion of sparse AMT data was shown to be effective in providing a good initial model for ZTEM inversion. Moreover, simultaneously inverting both data sets led to better results than the sequential approach by enabling to identify structural features that were difficult to resolve from the individual data sets.

Permeability measurements on rock samples from Unzen Scientific Drilling Project Drill Hole 4 (USDP-4)

NASA Astrophysics Data System (ADS)

Watanabe, Tohru; Shimizu, Yuhta; Noguchi, Satoshi; Nakada, Setsuya

2008-07-01

Permeability measurement was made on five rock samples from USDP-4 cores. Rock samples were collected from the conduit zone and its country rock. One sample (C14-1-1) is considered as a part of the feeder dyke for the 1991-1995 eruption. The transient pulse method was employed under confining pressure up to 50 MPa. Compressional wave velocity was measured along with permeability. The measured permeability ranges from 10 - 19 to 10 - 17 m 2 at the atmospheric pressure, and is as low as that reported for tight rocks such as granite. The permeability decreases with increasing confining pressure, while the compressional wave velocity increases. Assuming that pores are parallel elliptical tubes, the pressure dependence of permeability requires aspect ratio of 10 - 4 -10 - 2 at the atmospheric pressure. The pore aperture is estimated to be less than 1 μm. The estimated aspect ratio and pore aperture suggest that connectivity of pores is maintained by narrow cracks. The existence of cracks is supported by the pressure dependence of compressional wave velocity. Narrow cracks (< 1 μm) are observed in dyke samples, and they must have been created after solidification. Dyke samples do not provide us information of pore structures during degassing, since exsolved gas has mostly escaped and pores governing the gas permeable flow should have been lost. Both dyke and country rock samples provide us information of materials around ascending magma. Although the measured small-scale permeability cannot be directly applied to geological-scale processes, it gives constrains on studies of large-scale permeability.

75 FR 19647 - Agency Information Collection Activities; Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-15

... supporting documentation should be addressed to Karen Jagielski, Attorney, Division of Advertising Practices... submitted to: Office of Information and Regulatory Affairs, Office of Management and Budget, Attention: Desk...

Ocular Health (OH) Ultrasound 2 Scan

NASA Image and Video Library

2013-06-06

Astronaut Karen Nyberg,Expedition 37 flight engineer, assisted by astronaut Chris Cassidy, performs an Ocular Health (OH) Ultrasound 2 scan in the Destiny laboratory of the International Space Station.

76 FR 3906 - Sunshine Act Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-21

.... Closed Session 1. Staff Briefing on Economic Conditions and Impact on Stakeholders. 2. Docket No. 96-20... Regarding Passenger Vessel Financial Responsibility Requirements. CONTACT PERSON FOR MORE INFORMATION: Karen...

Ocular Health (OH) Fundoscope Exam

NASA Image and Video Library

2013-06-05

Astronaut Karen Nyberg and Astronaut Chris Cassidy (partially visible), both Expedition 37 flight engineers, perform an Ocular Health (OH) Fundoscope Exam in the Destiny laboratory of the International Space Station

Photos taken inside ISS during EVA day

NASA Image and Video Library

2013-07-09

Astronaut Karen Nyberg,Expedition 36 flight engineer,is photographed at the Space Station Remote Manipulator System (SSRMS) controls in the U.S. Laboratory during a session of extravehicular activity (EVA).

Mysterious Roving Rocks of Racetrack Playa

NASA Image and Video Library

2017-12-08

Some of the moving rocks are large. This one is about 10 inches tall. Researchers in the late 1960s and early 1970s documented the movements of one very large rock that they named Karen. (The two men named all the rocks after women.) They estimated that Karen weighed 700 pounds. Credit: NASA/GSFC/Maggie McAdam To read a feature story on the Racetrack Playa go to: www.nasa.gov/topics/earth/features/roving-rocks.html NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe. Follow us on Twitter Join us on Facebook

Office of Administrative Hearings

Science.gov Websites

Mandala (Anchorage) Kathryn L. Kurtz (Juneau) Lawrence A. Pederson (Anchorage) Jessica Leeah (Juneau ) Kathryn A. Swiderski (Anchorage) Karen L. Loeffler (Anchorage) Hearing Procedures for Fair Hearings and

MELFI ops

NASA Image and Video Library

2013-06-06

Astronaut Karen Nyberg,Expedition 36 flight engineer,works with samples in Minus Eighty-Degree Laboratory Freezer for ISS (MELFI-3) in the Destiny laboratory of the Earth-orbiting International Space Station.

76 FR 71591 - Notice of Revocation of Customs Broker Licenses

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-18

... Seattle Mary Freeman 09980 Seattle Jack Gillam 03890 Seattle Scott Kauffman 17560 Seattle De Illa Lamb 11978 Seattle Karen Lovely 10411 Seattle Lori Murvin 20341 Seattle Douglas Shaver 06888 Seattle Robert...

Genesis of the Hengling magmatic belt in the North China Craton: Implications for Paleoproterozoic tectonics

NASA Astrophysics Data System (ADS)

Peng, Peng; Guo, Jinghui; Zhai, Mingguo; Windley, Brian F.; Li, Tiesheng; Liu, Fu

2012-09-01

The 2200-1880 Ma igneous rocks in the central and eastern parts of the North China Craton (NCC) constitute a new Hengling magmatic belt (HMB), which includes the ~ 2147 Ma Hengling mafic sill/dyke swarm, the ~ 2060 Ma Yixingzhai mafic dyke swarm, and the ~ 1973 Ma Xiwangshan mafic dyke swarm. The three swarms are contiguous and have experienced variable degrees of metamorphism from greenschist to low amphibolite facies (Hengling), medium granulite facies (Yixingzhai), and medium/high-pressure granulite facies (Xiwangshan). They are all tholeiitic in composition typically with 47-52 wt.% SiO2 and 4-10 wt.% MgO, and all show light rare earth element enrichments and Nb- and Ta-depletion. Their Nd TDM ages are in the range of 2.5-3.0 Ga. Specifically, the Hengling and Yixingzhai dykes/sills are depleted in Th, U, Zr, Hf and Ti, whereas the Xiwangshan dykes are enriched in U and weakly depleted in other elements. Variable Sr-anomalies indicate significant feldspar accumulation (positive anomalies) or fractionation. The ɛNd(t) values of the three swarms are: - 3.2-+3.0 (Hengling), - 1.7-+ 1.8 (Yixingzhai) and - 1.4-+ 1.0 (Xiwangshan). These mafic representatives of the HMB originated from the > 2.5 Ga sub-continental lithospheric mantle of the NCC, and with A-type granites and other igneous associations in this belt they likely evolved in an intra-continental rift. The progressive changing compositions of the three swarms are interpreted in terms of their source regions at different depths, i.e., shallower and shallower through time. And the decrease in scale and size of the intrusions and their magma volumes indicate the progressive weakening of magmatism in this rift. The rocks in this belt are different chronologically, petrologically and chemically from those in the Xuwujia magmatic belt (XMB). We propose that the two magmatic belts represent two different magmatic systems in different blocks of the NCC, i.e., an eastern block (with the HMB) and a western block

Dynamics of the 2014-15 Bardarbunga-Holuhraun magma propagation

NASA Astrophysics Data System (ADS)

Caudron, C.; White, R. S.; Rivalta, E.

2016-12-01

The 2014-15 Holuhraun eruption was the largest eruption in Europe since 1784. During the two weeks preceding the eruption, the magma migrated from the south, around Bardarbunga volcano, to the north. This 48 km-long segmented propagation triggered, at a variable rate, more than 30,000 micro-earthquakes, and eventually discharged huge amount of lava and sulphur dioxide. A network comprising more than 70 seismometers captured the melt intrusion with an unprecedented resolution, providing scientists with a wealth of data to better understand volcano shallow magma storage and transport. This unique dataset first serves as a calibration of the seismic amplitude ratio methodology (Taisne et al., 2011), specifically designed to track the micro seismicity associated with magma migration, and better assess its limitations. The technique remarkably tracks magma propagations, even in the absence of earthquakes located using traditional techniques (based on P and S wave arrivals). This finding is in agreement with Bakker et al. (2016) who experimentally showed that the seismicity remain significant as long as magma movement continues. It also highlights intriguing systematic retreats of the seismicity to the back of each active segment. The seismic energy persists at this location for several hours (up to 80 hours), before surging again forward. This peculiar behaviour was also, although less clearly, observed during the Afar (Ethiopia) and Krafla (Iceland) intrusions. The shape of a dyke is controlled by the topographic and flow gradients. After calculating and low-passing the topographic gradient, the most intense migrations occur where the gradient is lower. Following advances at the tip of the dyke, the seismic activity retreats, the active seismic area becomes wider and correlates with larger modelled dyke openings (up to 6 m). Since the flow gradient in these settings is mostly determined by the difference in pressure between the head and the tail of the dyke, the active

An evolved axial melt lens in the Northern Ibra Valley, Southern Oman Ophiolite

NASA Astrophysics Data System (ADS)

Loocke, M. P.; Lissenberg, C. J.; MacLeod, C. J.

2014-12-01

The axial melt lens (AML) is a common feature lying at the base of the upper crust at fast-spreading mid-ocean ridges. It is thought to play a major role in the evolution of MORB and, potentially, accretion of the plutonic lower crust. In order to better understand the petrological processes that operate in AMLs we have examined the nature and variability of the horizon equivalent to the AML preserved in the Oman ophiolite. We present the results of a detailed investigation of a section east of Fahrah in the Ibra Valley. Here, a suite of 'varitextured' gabbros separates the sheeted dykes above from foliated gabbros below. It comprises 3 distinct units: an ophitic gabbro with pegmatitic patches (patchy gabbro; 70 m thick), overlain by a spotty gabbro (50 m), capped by a quartz-diorite (120 m). The sheeted dykes are observed to root in the quartz-diorite. Contacts between the plutonic units are gradational and subhorizontal. All of the units are isotropic. A total of 110 samples were collected for detailed petrographic and chemical analysis. With the exception of a small number of the diorites, all of the samples have a 'cumulate' component. Primary igneous amphibole is ubiquitous, present even as a minor phase in the foliated gabbros beneath, and indicating extensive differentiation and/or the presence of water in the primary liquid. France et al. (2014, Lithos) report patches of granoblastic material from this horizon in the Fahrah area, and suggest they represent the restites of partially melted pieces of the sheeted dykes. We did not, however, find any such granoblastic material, nor can the quartz-diorites represent partial melt; instead, preliminary geochemical modeling suggests that all of the units can be related by simple progressive fractional crystallization of an Oman axial ('V1' or 'Geotimes') melt. Along with the field relationships, as well as the basaltic andesite to dacite composition of the overlying sheeted dykes, this suggests that the AML was the

Insights on the injection mechanisms inferred from AMS fabrics of sand injectites in a turbiditic system, the exemple of Bevon area of the SE Basin (France).

NASA Astrophysics Data System (ADS)

Robion, Philippe; Mehl, Caroline

2016-04-01

We propose to investigate the set up mechanisms of sands injection in the case of dykes injected in host marls of Aptian-Albian age in the Vocontian basin (SE France). Several models have been proposed for a downward injection of the dyke in the Bevons area and we guess that AMS fabric investigations can be used to infer the flow direction. 144 drill cores distributed on 14 sites were sampled, among which 8 sites in the injectites and 6 sites in the host rocks. The studied dykes are generally of a few decimeters thick and are setting up in both in vertical or oblique position with respect to the subhorizontal bedding of the host rocks. There were sampled from one side to the other in order to track the flow direction by identification of imbricated fabric. Magnetic mineralogy, i.e. unblocking temperature inferred from IRM 3 axes demagnetization, indicates that the ferromagnetics s.l. mineralogy is dominated by an assemblage of magnetite (unblocking temperature Tub=580°C) and pyrrhotite (Tub=325°C). Magnetic susceptibility is low, typical for siliciclastic rocks, ranging from 4x10-5 up to 1.7x10-4 SI. Degree of magnetic anisotropy is likely representative of AMS measurements in sedimentary rocks with weak values, below than 5 %. In marly host rocks magnetic mineralogy is dominated by pyrrhotite associated with magnetite and both the magnetic susceptibility and degree of anisotropy are slightly lower than for injectites. Regarding magnetic fabric axes distribution, despite some dispersion, the results show that minimum axes of AMS (K3) are parallel to the dyke plane, and maximum axes (K1) are roughly in horizontal position. In marly host rocks, the magnetic fabric is related to tectonic shortening. We interpret that the host rocks have recorded the regional tectonic imprint while the magnetic fabric of the injectites are related to early sedimentary processes. The mechanism of set up proposed to explain the magnetic fabric in the Bevon injectites is a step

Presidential Green Chemistry Challenge: 1998 Academic Award (Draths and Frost)

EPA Pesticide Factsheets

Presidential Green Chemistry Challenge 1998 award winners, Dr. Karen M. Draths and Professor John W. Frost, used benign, genetically engineered microbes and sugars (instead of benzene) to synthesize adipic acid and catechol.

Nyberg with computer

NASA Image and Video Library

2013-09-29

ISS037-E-004299 (29 Sept. 2013) --- NASA astronaut Karen Nyberg, Expedition 37 flight engineer, uses a payload and general support computer (PGSC) in the Harmony node of the International Space Station.

The geochemistry and petrogenesis of an ophiolitic sequence from Pindos, Greece

NASA Astrophysics Data System (ADS)

Capedri, S.; Venturelli, G.; Bocchi, G.; Dostal, J.; Garuti, G.; Rossi, A.

1980-06-01

The ophiolites of Northern Pindos have been studied in a section close to the village of Perivoli (Grevena District). The section comprises cumulus rocks ranging from ultramafics to gabbros, overlain by dolerites (non-cumulus microgabbro) capped by thick frequently pillowed lava flows. The sequence is cut by basaltic dykes. While the cumulus rocks and the dolerites are mostly fresh, the lavas and dykes are strongly transformed. Major and trace element (Ni, Cr, Sc, Y, Zr, Nb, Sr, Ba, Zn, Cu, V, Li) data are presented for selected samples from the sequence. For some elements, the volcanic/subvolcanic rocks (flows, dykes, dolerites) exhibit wide chemical characteristics which are considered to mainly reflect variations within the parent magmas. Some lavas appear to be closely comparable with the present-day ocean-floor basalts, while other flows and most of the dykes are strongly depleted in some “incompatible” elements and are similar to some rocks from immature island arcs. The dolerites have transitional chemical features. The Pindos lavas differ from Western Mediterranean ophiolites in that the former have lower Ti,P,Zr,Y, higher Fe tot. and normally higher Ti/Zr ratio. The volcanic/subvolcanic rocks from Pindos have been derived from separate magmas. Some lavas were possibly produced by variable partial melting of an already depleted mantle source, while the lavas exhibiting ocean-floor affinity were probably generated by partial melting of a less depleted source. The wide chemical variations of the Pindos lavas cannot be easily explained by an ocean-ridge system. An “island arc-marginal basin system” could better account for the observed chemical features.

The trigger mechanism of low-frequency earthquakes on Montserrat

NASA Astrophysics Data System (ADS)

Neuberg, J. W.; Tuffen, H.; Collier, L.; Green, D.; Powell, T.; Dingwell, D.

2006-05-01

A careful analysis of low-frequency seismic events on Soufrièere Hills volcano, Montserrat, points to a source mechanism that is non-destructive, repetitive, and has a stationary source location. By combining these seismological clues with new field evidence and numerical magma flow modelling, we propose a seismic trigger model which is based on brittle failure of magma in the glass transition. Loss of heat and gas from the magma results in a strong viscosity gradient across a dyke or conduit. This leads to a build-up of shear stress near the conduit wall where magma can rupture in a brittle manner, as field evidence from a rhyolitic dyke demonstrates. This brittle failure provides seismic energy, the majority of which is trapped in the conduit or dyke forming the low-frequency coda of the observed seismic signal. The trigger source location marks the transition from ductile conduit flow to friction-controlled magma ascent. As the trigger mechanism is governed by the depth-dependent magma parameters, the source location remains fixed at a depth where the conditions allow brittle failure. This is reflected in the fixed seismic source locations.

75 FR 71785 - Senior Executive Service: Performance Review Board Members

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-24

.... Jonathan I. Carver, Chief Financial Officer and Associate Administrator for Performance Management. 3... Counsel. 5. Ana M. Ma, Chief of Staff. Karen G. Mills, Administrator. [FR Doc. 2010-29611 Filed 11-23-10...

77 FR 29594 - Gulf of Mexico Fishery Management Council; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-18

.... The SSC will also reconsider it earlier ABC recommendation for vermilion snapper in light of concern... returning fish to the water, a presentation on physiological effects of barotrauma by Dr. Karen Burns, a...

Nyberg in Node 1

NASA Image and Video Library

2013-08-13

Photo of Astronaut Karen Nyber,Expedition 36 flight engineer,with a snack of peanut butter and chocolate sandwiched between two waffles. Photo taken in the Node 1 module. Also sent as Twitter message.

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

Davenport, Karen

Karen Davenport of Los Alamos National Laboratory discusses a high-throughput next generation genome finishing pipeline on June 3, 2010 at the "Sequencing, Finishing, Analysis in the Future" meeting in Santa Fe, NM.

Nyberg with ARED in Node 3

NASA Image and Video Library

2013-06-03

ISS036-E-005939 (3 June 2013) --- NASA astronaut Karen Nyberg, Expedition 36 flight engineer, gets a workout on the Advanced Resistive Exercise Device (ARED) in the Tranquility node of the International Space Station.

Multi-user Droplet Combustion Apparatus (MDCA) Hardware Replacement

NASA Image and Video Library

2013-10-02

ISS037-E-004956 (2 Oct. 2013) --- NASA astronaut Karen Nyberg, Expedition 37 flight engineer, performs the Multi-user Droplet Combustion Apparatus (MDCA) hardware replacement in the Harmony node of the International Space Station.

Multi-user Droplet Combustion Apparatus (MDCA) Hardware Replacement

NASA Image and Video Library

2013-10-02

ISS037-E-004959 (2 Oct. 2013) --- NASA astronaut Karen Nyberg, Expedition 37 flight engineer, performs the Multi-user Droplet Combustion Apparatus (MDCA) hardware replacement in the Harmony node of the International Space Station.

Magmatic evolution of the Jbel Boho alkaline complex in the Bou Azzer inlier (Anti-Atlas/Morocco) and its relation to REE mineralization

NASA Astrophysics Data System (ADS)

Benaouda, Rachid; Holzheid, Astrid; Schenk, Volker; Badra, Lakhlifi; Ennaciri, Aomar

2017-05-01

The Jbel Boho complex (Anti-Atlas/Morocco) is an alkaline magmatic complex that was formed during the Precambrian-Cambrian transition, contemporaneous with the lower early Cambrian dolomite sequence. The complex consists of a volcanic sequence comprising basanites, trachyandesites, trachytes and rhyolites that is intruded by a syenitic pluton. Both the volcanic suite and the pluton are cut by later microsyenitic and rhyolitic dykes. Although all Jbel Boho magmas were probably ultimately derived from the same, intraplate or plume-like source, new geochemical evidence supports the concept of a minimum three principal magma generations having formed the complex. Whereas all volcanic rocks (first generation) are LREE enriched and appear to be formed by fractional crystallization of a mantle-derived magma, resulting in strong negative Eu anomalies in the more evolved rocks associated with low Zr/Hf and Nb/Ta values, the younger syenitic pluton displays almost no negative Eu anomaly and very high Zr/Hf and Nb/Ta. The syenite is considered to be formed by a second generation of melt and likely formed through partial melting of underplated mafic rocks. The syenitic pluton consists of two types of syenitic rocks; olivine syenite and quartz syenite. The presence of quartz and a strong positive Pb anomaly in the quartz syenite contrasts strongly with the negative Pb anomaly in the olivine syenite and suggests the latter results from crustal contamination of the former. The late dyke swarm (third generation of melt) comprises microsyenitic and subalkaline rhyolitic compositions. The strong decrease of the alkali elements, Zr/Hf and Nb/Ta and the high SiO2 contents in the rhyolitic dykes might be the result of mineral fractionation and addition of mineralizing fluids, allowing inter-element fractionation of even highly incompatible HFSE due to the presence of fluorine. The occurrence of fluorite in some volcanic rocks and the Ca-REE-F carbonate mineral synchysite in the dykes

Group Grammar

ERIC Educational Resources Information Center

Adams, Karen

2015-01-01

In this article Karen Adams demonstrates how to incorporate group grammar techniques into a classroom activity. In the activity, students practice using the target grammar to do something they naturally enjoy: learning about each other.

Nyberg in U.S. Laboratory

NASA Image and Video Library

2013-10-03

ISS037-E-006456 (3 Oct. 2013) --- NASA astronaut Karen Nyberg, Expedition 37 flight engineer, enters data into a computer near the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station.

Nyberg in U.S. Laboratory

NASA Image and Video Library

2013-10-03

ISS037-E-006458 (3 Oct. 2013) --- NASA astronaut Karen Nyberg, Expedition 37 flight engineer, enters data into a computer near the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station.

Ryazanskiy and Nyberg in Node 1

NASA Image and Video Library

2013-10-02

ISS037-E-005750 (2 Oct. 2013) --- NASA astronaut Karen Nyberg and Russian cosmonaut Sergey Ryazanskiy, both Expedition 37 flight engineers, look at a computer monitor in the Unity node of the International Space Station.

Research notes : roadway design treatments for rural to urban transitions.

DOT National Transportation Integrated Search

2008-12-01

An ODOT Research study, lead by Karen Dixon at Oregon State University, reviewed research evaluating potential traffic calming strategies for rural-to-urban transitions on high speed highways. Driving simulator evaluations were conducted to assess se...

77 FR 6825 - NASA Advisory Council; Information Technology Infrastructure Committee; Meeting.

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-09

...; Information Technology Infrastructure Committee; Meeting. AGENCY: National Aeronautics and Space... Information Technology Infrastructure Committee of the NASA Advisory Council. DATES: Wednesday, March 7, 2012... CONTACT: Ms. Karen Harper, Executive Secretary for the Information Technology Infrastructure Committee...

Petrogenesis and geodynamics of plagiogranites from Central Turkey (Ekecikdağ/Aksaray): new geochemical and isotopic data for generation in an arc basin system within the northern branch of Neotethys

NASA Astrophysics Data System (ADS)

Köksal, Serhat; Toksoy-Köksal, Fatma; Göncüoglu, M. Cemal

2017-06-01

In the Late Cretaceous, throughout the closure of the Neotethys Ocean, ophiolitic rocks from the İzmir-Ankara-Erzincan ocean branch were overthrusted the northern margin of the Tauride-Anatolide Platform. The ophiolitic rocks in the Ekecikdağ (Aksaray/Central Turkey) region typify the oceanic crust of the İzmir-Ankara-Erzincan branch of Neotethys. The gabbros in the area are cut by copious plagiogranite dykes, and both rock units are intruded by mafic dykes. The plagiogranites are leucocratic, fine- to medium-grained calc-alkaline rocks characterized mainly by plagioclase and quartz, with minor amounts of biotite, hornblende and clinopyroxene, and accessory phases of zircon, titanite, apatite and opaque minerals. They are tonalite and trondhjemite in composition with high SiO2 (69.9-75.9 wt%) and exceptionally low K2O (<0.5 wt%) contents. The plagiogranites in common with gabbros and mafic dykes show high large-ion lithophile elements/high-field strength element ratios with depletion in Nb, Ti and light rare-earth elements with respect to N-MORB. The plagiogranites together with gabbros and mafic dykes show low initial 87Sr/86Sr ratios (0.70419-0.70647), high ƐNd( T) (6.0-7.5) values with 206Pb/204Pb (18.199-18.581), 207Pb/204Pb (15.571-15.639) and 208Pb/204Pb (38.292-38.605) ratios indicating a depleted mantle source modified with a subduction component. They show similar isotopic characteristics to the other supra-subduction zone (SSZ) ophiolites in the Eastern Mediterranean to East Anatolian-Lesser Caucasus and Iran regions. It is suggested that the Ekecikdağ plagiogranite was generated in a short time interval from a depleted mantle source in a SSZ/fore-arc basin setting, and its nature was further modified by a subduction component during intra-oceanic subduction.

Magma Mingling of Multiple Mush Magmas

NASA Astrophysics Data System (ADS)

Graham, B.; Leitch, A.; Dunning, G.

2016-12-01

This field, petrographic, and geochemical study catalogues complicated magma mingling at the field to thin section scale, and models the emplacement of multiple crystal-rich pulses into a growing magma chamber. Modern theories present magma chambers as short-lived reservoirs that are continuously fed by intermittent magma pulses and suggest processes that occur within them can be highly dynamic. Differences in the rheology of two mingling magmas, largely affected by crystallinity, can result in varied textural features that can be preserved in igneous rocks. Field evidence of complex magma mingling is observed at Wild Cove, located along the northeast shoreline of Fogo Island, Newfoundland, an area interpreted to represent the roof/wall region of the Devonian Fogo Batholith. Fine-grained intermediate enclaves are contained in host rocks of similar composition and occur in round to amoeboid shapes. Dykes of similar composition are also observed near enclaves suggesting they were broken up into globules in localized areas. These provide evidence for a possible mechanism by which enclaves were formed as dykes passed through a more liquid-rich region of the magma chamber. The irregular but sharp nature of the boundaries between units suggest that all co-existed as "mushy" magmas with variable crystallinities reflecting a wide range in temperature between their respective liquidus and solidus. Textural evidence of complex mingling between mush units includes the intrusion of tonalite dykes into quartz diorite and granite mushes. The dykes were later pulled apart and subsequently back-intruded by liquid from the host mush (Figure). Observed magmatic tubes of intermediate magma cross-cutting through magma of near identical composition likely reflect compaction of the underlying mush after intrusion of new pulses of magma into the system. Petrographic examination of contacts between units reveals that few are chilled and medium to coarse grained boundaries are the norm.

Solidification effects on sill formation: An experimental approach

NASA Astrophysics Data System (ADS)

Chanceaux, L.; Menand, T.

2014-10-01

Sills represent a major mechanism for constructing continental Earth's crust because these intrusions can amalgamate and form magma reservoirs and plutons. As a result, numerous field, laboratory and numerical studies have investigated the conditions that lead to sill emplacement. However, all previous studies have neglected the potential effect magma solidification could have on sill formation. The effects of solidification on the formation of sills are studied and quantified with scaled analogue laboratory experiments. The experiments presented here involved the injection of hot vegetable oil (a magma analogue) which solidified during its propagation as a dyke in a colder and layered solid of gelatine (a host rock analogue). The gelatine solid had two layers of different stiffness, to create a priori favourable conditions to form sills. Several behaviours were observed depending on the injection temperature and the injection rate: no intrusions (extreme solidification effects), dykes stopping at the interface (high solidification effects), sills (moderate solidification effects), and dykes passing through the interface (low solidification effects). All these results can be explained quantitatively as a function of a dimensionless temperature θ, which describes the experimental thermal conditions, and a dimensionless flux ϕ, which describes their dynamical conditions. The experiments reveal that sills can only form within a restricted domain of the (θ , ϕ) parameter space. These experiments demonstrate that contrary to isothermal experiments where cooling could not affect sill formation, the presence of an interface that would be a priori mechanically favourable is not a sufficient condition for sill formation; solidification effects restrict sill formation. The results are consistent with field observations and provide a means to explain why some dykes form sills when others do not under seemingly similar geological conditions.

Faces in water bubbles

NASA Image and Video Library

2013-07-12

ISS036-E-018290 (12 July 2013) --- NASA astronaut Karen Nyberg, Expedition 36 flight engineer, squeezes a water bubble out of her beverage container, showing her image refracted, in the Unity node of the International Space Station.

Late Triassic (Carnian) lamproites from Noril'sk, polar Siberia: Evidence for melting of the recycled Archean crust and the question of lamproite source for some placer diamond deposits of the Siberian Craton

NASA Astrophysics Data System (ADS)

Ivanov, Alexei V.; Demonterova, Elena I.; Savatenkov, Valery M.; Perepelov, Alexander B.; Ryabov, Viktor V.; Shevko, Artem Y.

2018-01-01

Two typical lamproitic dykes were found in Noril'sk region of the north-western Siberian Craton, which according to mineralogical, geochemical and isotopic criteria belong to anorogenic, non-diamondiferous type of lamproites. According to the geologic relationships, they cut through the Noril'sk-1 intrusion of the Siberian flood basalt province and thus are younger than 251 Ma. 40Ar/39Ar dating of the two dykes yielded ages of 235.24 ± 0.19 Ma and 233.96 ± 0.19 Ma, showing that they were emplaced in Carnian of the Late Triassic, about 16 Ma after the flood basalt event. There are some indications that there were multiple lamproitic dyke emplacements, including probably emplacement of diamondiferous lamproites, which produced Carnian-age diamond-rich placer deposits in other parts of the Siberian Craton and in adjacent regions. Lead isotope modelling shows that the source of the studied lamproites was formed with participation of recycled crust, which underwent modification of its U/Pb ratio as early as 2.5 Ga. However, the exact mechanism of the recycling cannot be deciphered now. It could be either through delamination of the cratonic crust or subduction of a mix of ancient terrigenous sediments into the mantle transition zone.

Quantitative volcanic susceptibility analysis of Lanzarote and Chinijo Islands based on kernel density estimation via a linear diffusion process

NASA Astrophysics Data System (ADS)

Galindo, I.; Romero, M. C.; Sánchez, N.; Morales, J. M.

2016-06-01

Risk management stakeholders in high-populated volcanic islands should be provided with the latest high-quality volcanic information. We present here the first volcanic susceptibility map of Lanzarote and Chinijo Islands and their submarine flanks based on updated chronostratigraphical and volcano structural data, as well as on the geomorphological analysis of the bathymetric data of the submarine flanks. The role of the structural elements in the volcanic susceptibility analysis has been reviewed: vents have been considered since they indicate where previous eruptions took place; eruptive fissures provide information about the stress field as they are the superficial expression of the dyke conduit; eroded dykes have been discarded since they are single non-feeder dykes intruded in deep parts of Miocene-Pliocene volcanic edifices; main faults have been taken into account only in those cases where they could modified the superficial movement of magma. The application of kernel density estimation via a linear diffusion process for the volcanic susceptibility assessment has been applied successfully to Lanzarote and could be applied to other fissure volcanic fields worldwide since the results provide information about the probable area where an eruption could take place but also about the main direction of the probable volcanic fissures.

Quantitative volcanic susceptibility analysis of Lanzarote and Chinijo Islands based on kernel density estimation via a linear diffusion process

PubMed Central

Galindo, I.; Romero, M. C.; Sánchez, N.; Morales, J. M.

2016-01-01

Risk management stakeholders in high-populated volcanic islands should be provided with the latest high-quality volcanic information. We present here the first volcanic susceptibility map of Lanzarote and Chinijo Islands and their submarine flanks based on updated chronostratigraphical and volcano structural data, as well as on the geomorphological analysis of the bathymetric data of the submarine flanks. The role of the structural elements in the volcanic susceptibility analysis has been reviewed: vents have been considered since they indicate where previous eruptions took place; eruptive fissures provide information about the stress field as they are the superficial expression of the dyke conduit; eroded dykes have been discarded since they are single non-feeder dykes intruded in deep parts of Miocene-Pliocene volcanic edifices; main faults have been taken into account only in those cases where they could modified the superficial movement of magma. The application of kernel density estimation via a linear diffusion process for the volcanic susceptibility assessment has been applied successfully to Lanzarote and could be applied to other fissure volcanic fields worldwide since the results provide information about the probable area where an eruption could take place but also about the main direction of the probable volcanic fissures. PMID:27265878

Quantitative volcanic susceptibility analysis of Lanzarote and Chinijo Islands based on kernel density estimation via a linear diffusion process.

PubMed

Galindo, I; Romero, M C; Sánchez, N; Morales, J M

2016-06-06

Risk management stakeholders in high-populated volcanic islands should be provided with the latest high-quality volcanic information. We present here the first volcanic susceptibility map of Lanzarote and Chinijo Islands and their submarine flanks based on updated chronostratigraphical and volcano structural data, as well as on the geomorphological analysis of the bathymetric data of the submarine flanks. The role of the structural elements in the volcanic susceptibility analysis has been reviewed: vents have been considered since they indicate where previous eruptions took place; eruptive fissures provide information about the stress field as they are the superficial expression of the dyke conduit; eroded dykes have been discarded since they are single non-feeder dykes intruded in deep parts of Miocene-Pliocene volcanic edifices; main faults have been taken into account only in those cases where they could modified the superficial movement of magma. The application of kernel density estimation via a linear diffusion process for the volcanic susceptibility assessment has been applied successfully to Lanzarote and could be applied to other fissure volcanic fields worldwide since the results provide information about the probable area where an eruption could take place but also about the main direction of the probable volcanic fissures.

Nyamulagira’s magma plumbing system inferred from 15 years of InSAR

USGS Publications Warehouse

Wauthier, Christelle; Cayol, Valérie; Poland, Michael; Kervyn, François; D'Oreye, Nicolas; Hooper, Andrew; Samsonov, Sergei; Tiampo, Kristy; Smets, Benoit; Pyle, D. M.; Mather, T.A.; Biggs, J.

2013-01-01

Nyamulagira, located in the east of the Democratic Republic of Congo on the western branch of the East African rift, is Africa’s most active volcano, with an average of one eruption every 3 years since 1938. Owing to the socio-economical context of that region, the volcano lacks ground-based geodetic measurements but has been monitored by interferometric synthetic aperture radar (InSAR) since 1996. A combination of 3D Mixed Boundary Element Method and inverse modelling, taking into account topography and source interactions, is used to interpret InSAR ground displacements associated with eruptive activity in 1996, 2002, 2004, 2006 and 2010. These eruptions can be fitted by models incorporating dyke intrusions, and some (namely the 2006 and 2010 eruptions) require a magma reservoir beneath the summit caldera. We investigate inter-eruptive deformation with a multi-temporal InSAR approach. We propose the following magma plumbing system at Nyamulagira by integrating numerical deformation models with other available data: a deep reservoir (c. 25 km depth) feeds a shallower reservoir (c. 4 km depth); proximal eruptions are fed from the shallow reservoir through dykes while distal eruptions can be fed directly from the deep reservoir. A dyke-like conduit is also present beneath the upper southeastern flank of Nyamulagira.

Genetic structure and isolation by distance in a landrace of Thai rice

PubMed Central

Pusadee, Tonapha; Jamjod, Sansanee; Chiang, Yu-Chung; Rerkasem, Benjavan; Schaal, Barbara A.

2009-01-01

Rice is among the 3 most important crops worldwide. While much of the world's rice harvest is based on modern high-yield varieties, traditional varieties of rice grown by indigenous groups have great importance as a resource for future crop improvement. These local landraces represent an intermediate stage of domestication between a wild ancestor and modern varieties and they serve as reservoirs of genetic variation. Such genetic variation is influenced both by natural processes such as selection and drift, and by the agriculture practices of local farmers. How these processes interact to shape and change the population genetics of landrace rice is unknown. Here, we determine the population genetic structure of a single variety of landrace rice, Bue Chomee, cultivated by Karen people of Thailand. Microsatellite markers reveal high level of genetic variation despite predominant inbreeding in the crop. Bue Chomee rice shows slight but significant genetic differentiation among Karen villages. Moreover, genetically determined traits such as flowering time can vary significantly among villages. An unanticipated result was the overall pattern of genetic differentiation across villages which conforms to an isolation by distance model of differentiation. Isolation by distance is observed in natural plant species where the likelihood of gene flow is inversely related to distance. In Karen rice, gene flow is the result of farmers' seed sharing networks. Taken together, these data suggest that landrace rice is a dynamic genetic system that responds to evolutionary forces, both natural and those imposed by humans. PMID:19651617

pH and bacterial profile of dental plaque in children and adults of a low caries population.

PubMed

Raner, Elisabeth; Lindqvist, Lina; Johansson, Sofia; Hassan, Haidar; Carlén, Anette; Suksu-art, Narong; Dahlén, Gunnar

2014-06-01

This study compares pH and microbiological profile of dental plaque in children and adults of a low caries population. Thirty-nine children, 12-14 years of age and 45 adults between 20 and 39 years of age in 5 Karen villages of the Tak province, Northern Thailand were examined for plaque, calculus, caries (DMFT) and pH measurements in resting plaque and after a sucrose rinse. Information on dietary and oral hygiene habits was obtained through interviews using a fixed questionnaire. Microbiological profile of plaque samples was analyzed with DNA-DNA checkerboard technique. Mean DMFT was 0.77 ± 1.56 and 87% of the adults and 67% of the children were caries free (p < 0.05). The mean resting pH was for both age groups in the range of 7.0-7.1 and significantly higher than a Swedish caries free reference group. Karen adult men had significantly lower pH minimum than females and children (p < 0.05). Supragingival plaque samples showed high levels of low acidogenic and anaerobic species, which dominated over strong acid producers such as streptococci. The study indicates that the Karen children and adults has a plaque physiology and microbiology predominating by low acidogenic anaerobes, which in addition to the low sucrose intake explains the low caries prevalence in this population. Copyright © 2014 Elsevier Ltd. All rights reserved.

DOJ News Release: Boise Couple Sentenced for Defrauding Idaho DEQ

EPA Pesticide Factsheets

Jorge Garcia and Karen Damberg Garcia were sentenced today for conspiring to defraud the Idaho Department of Environmental Quality of federal grant funds that were to be used to install diesel emission reduction equipment on Idaho school buses.

76 FR 40765 - Texas Disaster #TX-00378

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-11

... Administrative declaration of a disaster for the State of Texas dated 07/05/2011. Incident: Dyer Mills Fire.... Karen G. Mills, Administrator. [FR Doc. 2011-17326 Filed 7-8-11; 8:45 am] BILLING CODE 8025-01-P ...

Faces in water bubbles

NASA Image and Video Library

2013-07-12

NASA astronaut Karen Nyberger, Expedition 36 flight engineer, watches a water bubble float freely between her and the camera, showing her image refracted in the droplet, while in the Node 1Unity module of the International Space Station.

76 FR 69609 - Amendment to Existing Validated End-User Authorizations in the People's Republic of China...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-09

... facilities. DATES: This rule is effective November 9, 2011. FOR FURTHER INFORMATION CONTACT: Karen Nies-Vogel...-User (VEU) BIS amended the EAR in a final rule on June 19, 2007 (72 FR 33646), creating a new... [[Page 69610

Intercultural Communications Skills Conference Proceedings (Townsville, Queensland, Australia, July 1-3, 1990).

ERIC Educational Resources Information Center

Migrant Resource Centre, Townsville (Australia).

This document contains 11 papers presented at a conference on multicultural issues such as cultural identity, stereotyping, and verbal and nonverbal communication: "Intercultural Communication--An Overview" (Karen Dennien); "Cultural Identity, Communication and Community Relations" (Lyn Trad); "Immigration to…

Geochronology and geochemistry of the granites from the Zhuxi W-Cu ore deposit in South China: Implication for petrogenesis, geodynamical setting and mineralization

NASA Astrophysics Data System (ADS)

Pan, Xiaofei; Hou, Zengqian; Zhao, Miao; Chen, Guohua; Rao, Jianfeng; Li, Yan; Wei, Jin; Ouyang, Yongpeng

2018-04-01

The giant Zhuxi tungsten deposit is located in the Taqian-Fuchun Ore Belt in northeastern Jiangxi province, and genetically associated with the Zhuxi granitic stocks and dykes. Three mineralization-related granites including granite porphyry dykes (GP), biotite granitic stocks (BG), and white granitic dykes (WG), were identified in the Zhuxi deposit. SHRIMP zircon U-Pb analysis for the three granitic rocks present ages ranging from 153.5 ± 1.0 Ma to 150.4 ± 1.0 Ma. The BG mainly contains quartz, microcline, albite, biotite and muscovite with minor accessory minerals including zircon, apatite, monazite, Ti/Fe oxides, and dolerite. However, the WG is mainly composed of quartz, microcline and albite with minor muscovite and accessory minerals. The GP is a medium-grained porphyritic granite and its phenocrysts include quartz, alkali feldspar, muscovite and plagioclase. All the Zhuxi granites have high SiO2 content (71.97 wt%-81.19 wt%) and total alkali (3.25 wt%-9.42 wt%), and their valid aluminum saturation index (ASI) values show a wide range of 1.03 to 2.49. High Rb/Sr ratios, low Sr content (<50 ppm) and markedly negative Eu anomalies of GP, WG and BG demonstrated that the Zhuxi granites are highly fractioned and intensive crystal differentiated. Because they display the features of both I- and S-types granites, they were confirmed to be I-S transform-type granites. Whole rock εNd(t) and zircon εHf(t) values fall into the ranges of -6.98 to -11.97, and -3.1 to -11.5, and the Nd (TDM2) and Hf two-stage model ages (TDMc) are 1.51-1.92 Ga and 1.42-2.01 Ga, respectively. Geochemical and isotopic data suggest that these highly fractionated I-S transform-type granites were originated from magmas which showed affinity with the Proterozoic continent and the Shuangqiaoshan Group and little mantle contribution was involved during the generation of Zhuxi granitic rocks. Extreme fractional crystallization resulted in further enrichment of tungsten in the evolved granitic

Nyberg with OGS R&R

NASA Image and Video Library

2013-07-19

ISS036-E-021797 (18 July 2013) --- NASA astronaut Karen Nyberg, Expedition 36 flight engineer, performs a remove and replace of the Oxygen Generation System (OGS) Hydrogen (H2) Sensor in the Tranquility node of the International Space Station.

FIR

NASA Image and Video Library

2013-09-16

ISS037-E-001115 (16 Sept. 2013) ---NASA astronaut Karen Nyberg, Expedition 37 flight engineer, works with test samples housed in the Light Microscopy Module (LMM) inside the Fluids Integrated Rack of the International Space Station’s Destiny laboratory.

Postsecondary Education for Individuals with Disabilities.

ERIC Educational Resources Information Center

Nathanson, Jeanne H., Ed.

1991-01-01

This newsletter theme issue contains several articles on postsecondary education for individuals with disabilities. "Supported Education for People with Psychiatric Disabilities...Issues and Implications" (Karen V. Unger) describes three prototypes for postsecondary education of individuals with psychiatric disabilities--the self-contained…

76 FR 15936 - Opportunity for Designation in the Aberdeen, SD; Decatur, IL; Hastings, NE; Fulton, IL; the State...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-22

... regular business hours (7 CFR 1.27(c)). FOR FURTHER INFORMATION CONTACT: Karen W. Guagliardo, 202-720-8262... State line east; Bounded on the East by the eastern South Dakota State line (the Big Sioux River) to... contiguous [[Page 15938

75 FR 16670 - 1-Propene, 2,3,3,3-tetrafluoro-; Withdrawal of Significant New Use Rule

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-02

... of Pollution Prevention and Toxics, Environmental Protection Agency, 1200 Pennsylvania Ave., NW... technical information contact: Karen Chu, Chemical Control Division (7405M), Office of Pollution Prevention... recordkeeping requirements. Dated: March 25, 2010. Barbara A. Cunningham, Acting Director, Office of Pollution...

United States Counter-narcotics Policies towards Burma, and How the Illegal Myanmar Regime is Manipulating Those Policies to Commit Ethnic Genocide

DTIC Science & Technology

2006-06-01

minority, insurgent, Southeast Asia, ASEAN, UN, United Nations, United Nations Security Council, Shan, Karen, Wa, yaa baa, methamphetamine , illicit... Methamphetamines ............................................................................63 B. ILLICT NARCOTIC TRANSPORTATION...129 x THIS PAGE INTENTIONALLY LEFT BLANK xi LIST OF FIGURES Figure 1. British Conquests

75 FR 70002 - Senior Executive Service Performance Review Board; Membership

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-16

... CONTACT: Karen D. Higginbotham, Director, Executive Resources Division, 3606A, Office of Human Resources... Human Resources, Office of Administration and Resources Management; William H. Benson, Director, Gulf Ecology Division, National Health and Environmental Effects Research Laboratory, Office of Research and...

Arsenic methylation phenotype affects accumulation and retention of arsenic in mice

EPA Science Inventory

Michael F. Hughes, Brenda C. Edwards, Karen M. Herbin-Davis, David J. Thomas, Pharmacokinetics Branch, ISTD, NHEERL, ORO, US EPA, Research Triangle Park, NC Enzymatically catalyzed methylation of arsenic (As) determines its systemic distribution and retention and its actions as a...

Vocational Education Today: Topical Issues.

ERIC Educational Resources Information Center

Kenway, Jane, Ed.; Tregenza, Karen, Ed.; Watkins, Peter, Ed.

This book contains 13 papers examining topical issues in vocational education and training (VET) in Victoria, Australia. The following papers are included: "Vocational Education and Schooling: The Changing Scene" (Jane Kenway, Sue Willis, Peter Watkins, Karen Tregenza); "The Enterprise Approach" (James Mulraney); "VET…

Vice President Pence Tours Jet Propulsion Laboratory

NASA Image and Video Library

2018-04-28

U.S. Vice President Mike Pence, 2nd from left, his wife Karen, and daughter Charlotte are given a tour of NASA's Jet Propulsion Laboratory by JPL Director Michael Watkins, Saturday, April 28, 2018 in Pasadena, California. Photo Credit: (NASA/Bill Ingalls)

Vice President Pence Tours Jet Propulsion Laboratory

NASA Image and Video Library

2018-04-28

U.S. Vice President Mike Pence, his wife Karen, and their daughter Charlotte shake hands with Mars Curiosity Mission ACE Walt Hoffman, right, during a tour of NASA's Jet Propulsion Laboratory, Saturday, April 28, 2018 in Pasadena, California. Photo Credit: (NASA/Bill Ingalls)

75 FR 52325 - Agency Information Collection Activities; Proposed Collection; Comment Request: Title IV of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-25

... the Public Health Security and Bioterrorism Preparedness and Response Act of 2002: Drinking Water... submitting comments. E-mail: [email protected] . Mail: EPA Water Docket, Environmental Protection Agency... . FOR FURTHER INFORMATION CONTACT: Karen Edwards, Water Security Division, Office of Ground Water and...

76 FR 53416 - Gulf of Mexico Fishery Management Council; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-26

... Ecosystem Scientific and Statistical Committee (SSC). DATES: The meeting will convene at 8 a.m. Eastern time... CONTACT: Dr. Karen Burns, Ecosystem Management Specialist; Gulf of Mexico Fishery Management Council; telephone: (813) 348-1630. SUPPLEMENTARY INFORMATION: The Ecosystem Scientific and Statistical Committee...

METHODS TO EVALUATE ARSENIC BIOAVAILABILITY ASSOCIATED WITH THE PRESENCE OF CCA-TREATED WOOD PRODUCTS

EPA Science Inventory

This is an invited paper to be presented by Dr. Karen Bradham at the 8th International Conference on the Biogeochemistry of Trace Elements, Adelaide, Australia, April 3 - 7, 2005. The abstract describes methods to evaluate arsenic bioavailability associated with the presence of ...

Cryptography: It’s Not Just For Electronic Mail Anymore

DTIC Science & Technology

1993-03-01

David Chaum . Security without identification: Transaction systems to make big brother obsolete. Communications of the ACM, 28(10): 1030-1044, Oc- tober...Jeannette Wing, Maurice Herlihy, Stewart Clamen, David Detlefs, Karen Kietzke, Richard Lerner, and Su-Yuen Ling. The Avalon language: A tutorial

Association appoints new RCN A&E Chair.

PubMed

1999-09-01

Lynda Holt, A&E Clinical Manager at Warwick Hospital has become Chair of the RCN A&E Nursing Association following the resignation of Karen Castille who has been seconded to the Department of Health (England) to work on the A&E modernisation programme.

KSC-2012-4150

NASA Image and Video Library

2012-07-31

CAPE CANAVERAL, Fla. – Eliza Montgomery, right, talks to Dr. Mason Peck, NASA's chief technologist, inside the Corrosion lab at NASA's Kennedy Space Center in Florida as David Steitz, left, and Karen Thompson, Kennedy's chief technologist, look on. Photo credit: NASA/Jim Grossmann

76 FR 70131 - Senior Executive Service Performance Review Board; Membership

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-10

... CONTACT: Karen D. Higginbotham, Director, Executive Resources Division, 3606A, Office of Human Resources... executive. Members of the 2011 EPA Performance Review Board are: William H. Benson, Director, Gulf Ecology...), Director, Executive Resources Division, Office of Human Resources, Office of Administration and Resources...

Proceedings of the Annual Midwest Research-to-Practice Conference in Adult, Continuing and Community Education (16th, East Lansing, Michigan, October 15-17, 1997).

ERIC Educational Resources Information Center

Levine, S. Joseph, Ed.

This proceedings contains 29 presentations: "Meaning of Participating in Technology Training" (Cynthia S. Blodgett-McDeavitt); "Applying Actor Network Theory to Curricular Change in Medical Schools" (Karen V. Busch); "Politics of Humanism" (Mary Katherine Cooper); "Reasons for the Nonparticipation of Adults in…

78 FR 12617 - Grants for the Rural Veterans Coordination Pilot (RVCP)

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-25

... or transporting medical or mental health providers to veterans; and providing assistance in obtaining... March 27, 2013. FOR FURTHER INFORMATION CONTACT: Karen Malebranche, Veterans Health Administration, Office of Interagency Health Affairs (10P5), 810 Vermont Avenue NW., Washington, DC 20420, telephone (202...

75 FR 32519 - Small Business Size Standards: Waiver of the Nonmanufacturer Rule

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-08

... (Compressed and Liquefied Gases), under NAICS code 325120 (Industrial Gases Manufacturing). On March 23, 2010...), under NAICS code 325120 (Industrial Gases Manufacturing). Dated: June 1, 2010. Karen Hontz, Director... Propane Gas (LPG), North American Industry Classification System (NAICS) code 325120, Product Service Code...

Leveraging Information Technology. Track IV: Support Services.

ERIC Educational Resources Information Center

CAUSE, Boulder, CO.

Seven papers from the 1987 CAUSE conference's Track IV, Support Services, are presented. They include: "Application Development Center" (John F. Leydon); "College Information Management System: The Design and Implementation of a Completely Integrated Office Automation and Student Information System" (Karen L. Miselis);…

MinneTESOL/WITESOL Journal, 2000-2001.

ERIC Educational Resources Information Center

Upton, John, Ed.

2001-01-01

These two journal issues present articles on the following: "Understanding and Teaching American Cultural Thought through English Metaphors" (Carl Zhonggang Gao); "An Alternative Model for Novice-Level Elementary ESL Education" (Karen Duke, Ann Mabbott); "Wisconsin's Approach to Academic Assessment for Limited-English…

Interaction of coeval felsic and mafic magmas from the Kanker granite, Pithora region, Bastar Craton, Central India

NASA Astrophysics Data System (ADS)

Elangovan, R.; Krishna, Kumar; Vishwakarma, Neeraj; Hari, K. R.; Ram Mohan, M.

2017-10-01

Field and petrographic studies are carried out to characterize the interactions of mafic and felsic magmas from Pithora region of the northeastern part of the Bastar Craton. The MMEs, syn-plutonic mafic dykes, cuspate contacts, magmatic flow textures, mingling and hybridization suggest the coeval emplacement of end member magmas. Petrographic evidences such as disequilibrium assemblages, resorption textures, quartz ocelli, rapakivi and poikilitic textures suggest magma mingling and mixing phenomena. Such features of mingling and mixing of the felsic and mafic magma manifest the magma chamber processes. Introduction of mafic magmas into the felsic magmas before initiation of crystallization of the latter, results in hybrid magmas under the influence of thermal and chemical exchange. The mechanical exchange occurs between the coexisting magmas due to viscosity contrast, if the mafic magma enters slightly later into the magma chamber, then the felsic magma starts to crystallize. Blobs of mafic magma form as MMEs in the felsic magma and they scatter throughout the pluton due to convection. At a later stage, if mafic magma enters the system after partial crystallization of felsic phase, mechanical interaction between the magmas leads to the formation of fragmented dyke or syn-plutonic mafic dyke. All these features are well-documented in the study area. Field and petrographic evidences suggest that the textural variations from Pithora region of Bastar Craton are the outcome of magma mingling, mixing and hybridization processes.

78 FR 26349 - Lock+TM

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-06

... tubes that would be incorporated into the dyke; (5) a 69 kilovolt transmission line conveying the....asp . You must include your name and contact information at the end of your comments. For assistance...

78 FR 56703 - SES Performance Review Board

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-13

... FEDERAL TRADE COMMISSION SES Performance Review Board AGENCY: Federal Trade Commission. ACTION... Performance Review Board. FOR FURTHER INFORMATION CONTACT: Karen Leydon, Chief Human Capital Officer, Federal... INFORMATION: Publication of the Performance Review Board (PRB) membership is required by 5 U.S.C. 4314(c)(4...

78 FR 28596 - Notice of Agreement Filed

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-15

... FEDERAL MARITIME COMMISSION Notice of Agreement Filed The Commission hereby gives notice of the... on the agreement to the Secretary, Federal Maritime Commission, Washington, DC 20573, within ten days... requested expedited review. Dated: May 10, 2013. By Order of the Federal Maritime Commission. Karen V...

78 FR 59359 - Notice of Agreements Filed

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-26

... FEDERAL MARITIME COMMISSION Notice of Agreements Filed The Commission hereby gives notice of the... on the agreements to the Secretary, Federal Maritime Commission, Washington, DC 20573, within ten... other hand. By Order of the Federal Maritime Commission. Dated: September 20, 2013. Karen V. Gregory...

Proceedings of the Annual Mid-South Instructional Technology Conference (6th, Murfreesboro, Tennessee, April 8-10, 2001).

ERIC Educational Resources Information Center

Middle Tennessee State Univ., Murfreesboro.

This proceedings of the sixth annual Mid-South Instructional Technology Conference contains the following papers: "They're Not Just Big Kids: Motivating Adult Learners" (Karen Jarrett Thoms); "A Computer Integrated Biology Laboratory Experience" (James B. Kring); "Building Web Sites for Mathematics Courses: Some Answers to…

75 FR 17394 - Notice of Availability of Government-Owned Inventions; Available for Licensing

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-06

... CFR part 404. Applications will be evaluated utilizing the following criteria: (1) Ability to... Jean Miller, Edward Unsworth, William Hook, Thomas Walsh, Karen Gray, and Charles Macri; 12/634,119... CONTACT: Dr. Charles Schlagel, Director, Office of Technology Transfer, Naval Medical Research Center, 503...

78 FR 52513 - Senior Executive Service Performance Review Board Membership

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-23

.... Anne L. Richards--Assistant Inspector General for Audits. Frank W. Deffer--Assistant Inspector General... General for Audit. Steven H. Rickrode, Jr.--Deputy Assistant Inspector General for Audit. Karen L. Ellis.... Kenneth P. Moorefield--Deputy Inspector General for Special Plans and Operations. James L. Pavlik...

Content Analysis in Systems Engineering Acquisition Activities

DTIC Science & Technology

2016-04-30

Acquisition Activities Karen Holness, Assistant Professor, NPS Update on the Department of the Navy Systems Engineering Career Competency Model Clifford...systems engineering toolkit . Having a common analysis tool that is easy to use would support the feedback of observed system performance trends from the

Hepatitis A - Multiple Languages

MedlinePlus

... gaw Karen) Khmer (ភាសាខ្មែរ) Kinyarwanda (Rwanda) Korean (한국어) Marshallese (Ebon) Nepali (नेपाली) Oromo ( ... PDF Centers for Disease Control and Prevention Kinyarwanda (Rwanda) Expand Section Vaccine Information Statement (VIS) -- Hepatitis A ...

Haemophilus Infections - Multiple Languages

MedlinePlus

... gaw Karen) Khmer (ភាសាខ្មែរ) Kinyarwanda (Rwanda) Korean (한국어) Nepali (नेपाली) Oromo (Afan Oromoo) ... PDF Centers for Disease Control and Prevention Kinyarwanda (Rwanda) Expand Section Vaccine Information Statement (VIS) -- Haemophilus Influenzae ...

Teacher Education. Case Studies in TESOL Practice Series.

ERIC Educational Resources Information Center

Johnson, Karen E., Ed.

Chapters in this volume include the following: "Innovations in TESOL Teacher Education: A Quiet Revolution" (Karen E. Johnson); "Building Bridges among University, School, and Community" (Donald F. Hones); "Sustainable Strategies for Professional Development in Education Reform" (Nancy Clair, Carolyn Temple Adger); "Developing Professionals:…

In Memoriam

NASA Astrophysics Data System (ADS)

Robert D. Elliott died on 12 April 2002, at age 87. He was a retired life member (Atmospheric Sciences) who joined AGU in 1944.Karen Harvey died on 30 April 2002, at age 59. She had been an AGU member (Heliospheric Physics) since 1992.

ARSENIC BIOAVAILABILITY ASSOCIATED WITH THE PRESENCE OF CCA-TREATED WOOD PRODUCTS

EPA Science Inventory

This is an invited paper/slide presentation to be presented by Dr. Karen Bradham at the 8th International Conference on the Biogeochemistry of Trace Elements, Adelaide, Australia, April 3 - 7, 2005. The PowerPoint slides describe the study design of projects currently being perf...

The Year of the Family. Presentations at Children's Rights Council National Conference (8th, Bethesda, Maryland, April 13-17, 1994).

ERIC Educational Resources Information Center

National Council for Children's Rights, Washington, DC.

Dealing predominantly with issues related to divorce and custody, this conference proceedings contains 20 papers or summaries; they are: (1) "Choices, Challenges, Changes" (Constance Ahrons); (2) "The History of the Joint Custody Movement" (Karen DeCrow); (3) "Children Held Hostage: Dealing with Programmed and Brainwashed…

78 FR 3317 - Removal of Persons From the Entity List Based on Removal Request; Implementation of Entity List...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-16

... the Entity List. The ERC's decision to remove these two persons took into account their cooperation... INFORMATION CONTACT: Karen Nies-Vogel, Chair, End-User Review Committee, Office of the Assistant Secretary..., Fax: (202) 482-3911, Email: [email protected] . SUPPLEMENTARY INFORMATION: Background The Entity List...

77 FR 66935 - Telephone Consumer Protection Act of 1991

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-08

... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 64 [CG Docket No. 02-278; FCC 12-21] Telephone Consumer Protection Act of 1991 AGENCY: Federal Communications Commission. ACTION: Final rule; correction...: Karen Johnson, Consumer and Governmental Affairs Bureau, Consumer Policy Division, at (202) 418- 7706 or...

New Website Helps You Find What You Need | Poster

Cancer.gov

By Karen Surabian, Contributing Writer The National Cancer Institute’s Technology Transfer Center (NCI’s TTC) recently launched a redesign of its website. New graphics, color scheme, and updated features provide a user-friendly environment for finding information related to technology transfer at NCI.

Teaching Ethics.

ERIC Educational Resources Information Center

Shellogg, Kathy M.; And Others

1988-01-01

Student activities professionals have a role in teaching ethics on campuses. Teaching ethics is defined as "the process of teaching ethical decision making." Karen Strohm Kitchener's "Model of Ethical Decision Making" provides a framework to be used when looking at an ethical problem. (MLW)

Grand Conversations across Texts

ERIC Educational Resources Information Center

Crafton, Linda K., Ed.; Johnson, Nancy J., Ed.

2008-01-01

This issue of "School Talk" brings together the ideas of purposefulness and intertextuality together in a teaching practice called intentional intertextual inquiry. "Making Inquiry Intentional and Intertextual" (Karen Smith, Sarah Diaz, and Silvia Edgerton) discusses the framework that combines inquiry-based learning and intertextuality within…

75 FR 36067 - Agency Information Collection Activities; Proposed Collection; Comment Request; Chemical-Specific...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-24

... section 8(a) to evaluate the potential for adverse human health and environmental effects caused by the... Office (7407M), Office of Pollution Prevention and Toxics (OPPT), Environmental Protection Agency, 1200... technical information contact: Karen Chu, Chemical Control Division (7405M), Office of Pollution Prevention...

77 FR 34024 - New England Fishery Management Council; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-08

... Street, Mill 2, Newburyport, MA 01950. FOR FURTHER INFORMATION CONTACT: Paul J. Howard, Executive... Genovese, Ph.D. Northeast University; (5) Ecological Role of Adult and Juvenile Anadromous Forage fish in Downeast Maine Estuaries: Sea-run Alewife and Groundfish Prey-- NEC Report, Karen Wilson, University of...

Mineral equilibria and zircon, garnet and titanite U-Pb ages constraining the PTt path of granite-related hydrothermal systems at the Big Bell gold deposit, Western Australia

NASA Astrophysics Data System (ADS)

Mueller, Andreas G.; McNaughton, Neal J.

2018-01-01

The Big Bell deposit (75 t gold) is located in a narrow spur of the Meekatharra greenstone belt, Yilgarn Craton, Western Australia. Two ore bodies are located in a calcic-potassic contact alteration zone overprinting lineated granodiorite dykes and amphibolite: almandine-cummingtonite-hornblende skarn (1-3 g/t Au, 1700 g/t As, 330 g/t W) and the muscovite-microcline gneiss (3-5 g/t Au, 580 g/t Sb, 620 g/t W) of the Main Lode. Genetic models vary from pre- to post-metamorphic replacement. Hornblende-plagioclase pairs in amphibolite constrain peak metamorphic temperature to 670 ± 50 °C. In contrast, garnet-biotite thermometry provides estimates of 578 ± 50 and 608 ± 50 °C for garnet-cordierite-biotite schist bordering the skarn and enveloping the Main Lode. Garnet-cordierite and garnet-hornblende pairs extend the range of fluid temperature to 540 ± 65 °C, well below peak metamorphic temperature. At 540-600 °C, the alteration assemblage andalusite + sillimanite constrains pressure to 300-400 MPa corresponding to 11-14 km crustal depth. Published U-Pb ages indicate that metamorphism took place in the aureole of the southeast granodiorite-tonalite batholith (2740-2700 Ma), followed by gold mineralization at 2662 ± 5 Ma and by the emplacement of biotite granite and Sn-Ta-Nb granite-pegmatite dykes at 2625-2610 Ma. Amphibolite xenoliths in granite northwest of the deposit record the lowest temperature (628 ± 50 °C), suggesting it lacks a metamorphic aureole. The rare metal dykes are spatially associated with epidote-albite and andradite-diopside skarns (≤1.5 g/t Au), mined where enriched in the weathered zone. We analysed hydrothermal zircon intergrown with andradite. Concordant U-Pb ages of 2612 ± 7 and 2609 ± 10 Ma confirm the presence of a second granite-related system. The zircons display oscillatory zoning and have low Th/U ratios (0.05-0.08). Low-Th titanite from an albite granite dyke has a concordant but reset U-Pb age of 2577 ± 7 Ma.

Video monitoring reveals pulsating vents and propagation path of fissure eruption during the March 2011 Pu'u 'Ō'ō eruption, Kilauea volcano

NASA Astrophysics Data System (ADS)

Witt, Tanja; Walter, Thomas R.

2017-01-01

Lava fountains are a common eruptive feature of basaltic volcanoes. Many lava fountains result from fissure eruptions and are associated with the alignment of active vents and rising gas bubbles in the conduit. Visual reports suggest that lava fountain pulses may occur in chorus at adjacent vents. The mechanisms behind such a chorus of lava fountains and the underlying processes are, however, not fully understood. The March 2011 eruption at Pu'u 'Ō'ō (Kilauea volcano) was an exceptional fissure eruption that was well monitored and could be closely approached by field geologists. The fissure eruption occurred along groups of individual vents aligned above the feeding dyke. We investigate video data acquired during the early stages of the eruption to measure the height, width and velocity of the ejecta leaving eight vents. Using a Sobel edge-detection algorithm, the activity level of the lava fountains at the vents was determined, revealing a similarity in the eruption height and frequency. Based on this lava fountain time series, we estimate the direction and degree of correlation between the different vents. We find that the height and velocity of the eruptions display a small but systematic shift in time along the vents, indicating a lateral migration of lava fountaining at a rate of 11 m/s from W to E. This finding is in agreement with a propagation model of a pressure wave originating at the Kilauea volcano and propagating through the dyke at 10 m/s from W to E. Based on this approach from videos only 30 s long, we are able to obtain indirect constraints on the physical dyke parameters, with important implications for lateral magma flow processes at depth. This work shows that the recording and analysis of video data provide important constraints on the mechanisms of lava fountain pulses. Even though the video sequence is short, it allows for the confirmation of the magma propagation direction and a first-order estimation of the dyke dimensions.

Morphological features of Miocene submarine coherent lavas from the ``Green Tuff'' basins: examples from basaltic and andesitic rocks from the Shimokita Peninsula, northern Japan

NASA Astrophysics Data System (ADS)

Yamagishi, Hiromitsu

1991-04-01

Basaltic and andesitic volcanic rocks of Miocene age exposed in the Shimokita Peninsula, northern Japan, illustrate morphological features of typical submarine coherent lavas of the “Green Tuff” basins in Japan. They are pillow lobes with surface structures, such as ropey wrinkles, corrugations, spreading cracks and tensional cracks, and lava lobes composed of a lithic core and glassy border zone or rim with an in-situ breccia zone grading outward into surrounding hyaloclastite. In addition they include massive lavas with columnar joints, and jointed dykes. The submarine coherent lavas and dykes are commonly associated with hyaloclastic breccias, such as pillow fragment breccia and angular fragment breccia. The descriptions of the Miocene volcanic rocks in the Shimokita Peninsula provide good criteria for recognition of submarine coherent lavas of basalt and andesite.

Genesis of rare-metal pegmatites and alkaline apatite-fluorite rocks of Burpala massi, Northern Baikal folded zone

NASA Astrophysics Data System (ADS)

Sotnikova, Irina; Vladykin, Nikolai

2015-04-01

Burpalinsky rare metal alkaline massif in the Northern Baikal folded zone in southern margin of Siberian Platform, is a of intrusion central type, created 287 Ma covering area of about 250 km2. It is composed of nepheline syenites and pulaskites grading to quartz syenites in the contacts. Veines and dykes are represented by shonkinites, sodalite syenite, leucocratic granophyres, alkali granites and numerous rare metal alkaline syenite pegmatites and two dykes of carbonatites. All rocks except for granites are cut by a large apatite-fluorite dyke rocks with mica and magnetite, which in turn is cut by alaskite granites dyke. The massif has been studied by A.M. Portnov, A.A. Ganzeev et al. (1992) Burpalinsky massif is highly enriched with trace elements, which are concentrated in pegmatite dykes. About 70 rare-metal minerals we found in massif. Zr-silicates: zircon, eudialyte, lovenite, Ti-lovenite, velerite, burpalite, seidozerite, Ca- seidozerite, Rosenbuschite, vlasovite, katapleite, Ca-katapleite, elpidite. Ti- minerals:- sphene, astrophyllite, ramsaite, Mn-neptunite bafertisite, chevkinite, Mn-ilmenite, pirofanite, Sr-perrerit, landauite, rutile, anatase, brookite; TR- minerals - loparite, metaloparite, britolite, rinkolite, melanocerite, bastnesite, parisite, ankilite, monazite, fluocerite, TR-apatite; Nb- minerals - pyrochlore, loparite. Other rare minerals leucophanite, hambergite, pyrochlore, betafite, torite, thorianite, tayniolite, brewsterite, cryolite and others. We have proposed a new scheme massif: shonkinites - nepheline syenites - alkaline syenite - quartz syenites - veined rocks: mariupolites, rare-metal pegmatites, apatite, fluorite rock alyaskite and alkaline granites and carbonatites (Sotnikova, 2009). Apatite-fluorite rocks are found in the central part of massif. This is a large vein body of 2 km length and a 20 m width cutting prevailing pulaskites. Previously, these rocks were regarded as hydrothermal low-temperature phase. New geological and

The geology of the northern tip of the Arabian-Nubian Shield

NASA Astrophysics Data System (ADS)

Beyth, M.; Eyal, Y.; Garfunkel, Z.

2014-11-01

Recently, a detailed (1:50,000) geological map of the Elat area, southern Israel was published. Attached to this map is a stratigraphic table of the Neoproterozoic metamorphic-magmatic complex of the study area. The Neoproterozoic basement in the Elat area encapsulates the Arabian Nubian Shield (ANS) geologic evolution. Uranium-Lead and Lead-Lead zircon ages, included in previous studies and referred to in this paper, reveal that these rocks were formed during more than 300 million years of Neoproterozoic time. The major process controlling the formation of the ANS as part of the East African Orogen is the closure of the Mozambique Ocean. The first orogenic phase in the Elat area, represented by the metamorphic rocks, includes the development of an island arc, erosion of the islands and deposition, and metamorphism. This event took place between ∼950 Ma and 780-790 Ma. Elat Schist, the oldest metamorphic rock in the area, was deformed and then intruded by quartz dioritic and granitic plutons that were later deformed and metamorphosed. The amphibolite metamorphic rock facies indicate metamorphic conditions of up to 650 °C and between 4 and 5 kbar. The peak of the metamorphic event was most probably before 750 Ma. A gradual change from compressional to extensional stress regime is evidenced by emplacement andesitic magnesium-rich dykes dated to 705 Ma that were later metamorphosed to schistose dykes at a greenschist metamorphic facies. The second orogenic phase (terrane amalgamation, main shaping of crust) was associated with the emplacement of large volumes (>50% of area) of calc-alkaline intrusions in a post-collision setting. These very last stages of metamorphism and deformation are characterized by intrusion of ∼630 Ma granitoids exhibiting some foliation. Pluton emplacement continued also after the end of deformation. Exhumation and transition to an extensional regime is recorded by the intrusion of shallow alkaline granites in ∼608 Ma which were

76 FR 76411 - Notice of Agreements Filed

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-07

... FEDERAL MARITIME COMMISSION Notice of Agreements Filed The Commission hereby gives notice of the... on the agreements to the Secretary, Federal Maritime Commission, Washington, DC 20573, within ten... of the Federal Maritime Commission. Karen V. Gregory, Secretary. [FR Doc. 2011-31443 Filed 12-6-11; 8...

CLONING, EXPRESSION, AND CHARACTERIZATION OF RAT S-ADENOSYL-L-METHIONINE: ARSENIC (III) METHYLTRANSFERASE (CYT19)

EPA Science Inventory

CLONING, EXPRESSION, AND CHARACTERIZATION OF RAT S-ADENOSYL-L-METHIONINE: ARSENIC(III) METHYLTRANSFERASE (cyt19)

Stephen B. Waters1 , Felicia Walton1 , Miroslav Styblo1 , Karen Herbin-Davis2, and David J. Thomas2 1 School of Medicine, University of North Carolina at Chape...

ATV ops

NASA Image and Video Library

2013-06-18

ISS036-E-009256 (18 June 2013) --- NASA astronauts Chris Cassidy and Karen Nyberg, both Expedition 36 flight engineers, perform cargo operations in the European Space Agency's Automated Transfer Vehicle-4 (ATV-4) "Albert Einstein" currently docked to the Zvezda Service Module of the International Space Station.

"A Clash of Two Worlds"; Disjuncture between the Norms and Values Held by Educational Practitioners and Parents of Children with Behavioural, Emotional and Social Difficulties

ERIC Educational Resources Information Center

Broomhead, Karen

2014-01-01

This article, by Karen Broomhead of Liverpool John Moores University, discusses an exploration of the clashing norms, values and expectations of parenting behaviours between parents of children with behavioural, emotional and social difficulties (BESD) and practitioners. Semi-structured interviews with 15 education professionals, employed in both…

Integrating Learning and Performance.

ERIC Educational Resources Information Center

1998

This document contains four papers from a symposium on integrating learning and performance in human resource development (HRD). "Action Imperatives that Impact Knowledge Performance and Financial Performance in the Learning Organization: An Exploratory Model" (Gary L. Selden, Karen E. Watkins, Thomas Valentine, Victoria J. Marsick)…

Humor. Beginnings Workshop.

ERIC Educational Resources Information Center

Elkind, David; Parr, Jerry; Duffy, Vincent; Strader, Bill; Stephens, Karen

2000-01-01

Presents five articles on humor in early child care: (1) "What Makes Young Children Laugh?" (David Elkind); (2) "Humor as a Tool in the Workplace" (Jerry Parr); (3) "Vincent's Vignettes" (Vincent Duffy); (4) "Family Humor" (Bill Strader); and (5) "Books to Tickle Funny Bones" (Karen Stephens). (SD)

Sprog, kultur, intersprog (Language, Culture, Interlanguage). ROLIG-Papir 57.

ERIC Educational Resources Information Center

Risager, Karen, Ed.

Four articles on language, culture, and interlanguage are included in this volume. The first by Karen Risager, "Sprog, kultur, og internationalisering" ("Language, Culture, and Internationalization") takes issue with the very broad perception that foreign language and culture cannot be separated in instruction. The second article,…

Language, Gesture, and Space.

ERIC Educational Resources Information Center

Emmorey, Karen, Ed.; Reilly, Judy S., Ed.

A collection of papers addresses a variety of issues regarding the nature and structure of sign language, gesture, and gesture systems. Articles include: "Theoretical Issues Relating Language, Gesture, and Space: An Overview" (Karen Emmorey, Judy S. Reilly); "Real, Surrogate, and Token Space: Grammatical Consequences in ASL American…

Information Technology: Making It All Fit. Track IV: Organization and Personnel Issues.

ERIC Educational Resources Information Center

CAUSE, Boulder, CO.

Seven papers from the 1988 CAUSE conference's Track IV, Organization and Personnel Issues, are presented. They include: "Positive Management: Techniques and Retreats" (Janet Wixson); "Data Administration: What Is It, Where Is It, How Is It Done?" (Karen L. Miselis, Lawrence A. Jordan, and Ronald Hoover); "The Departmental…

Proof-of-Principle High Speed Electronic Imaging System. Phase 2.

DTIC Science & Technology

1988-03-01

Winchenbach George Streckmann I Martha Martinez John Krieger Joe Parker John Morris Ann Coverston ." Karen Hollis Gregg Abate I... , .. ", .t ii i...R. J. Kelley, manager of the research facility, allocated space and locations for the equipment, and assigned John Krieger , technician, to us to

77 FR 13508 - Certainty of Terms of Service Contracts and NVOCC Service Arrangements

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-07

... in a service contract with a carrier, although their experience with such index- linked contracts is... adjust based upon an index reflecting changes in market conditions. DATES: The Final Rule is effective March 7, 2012. FOR FURTHER INFORMATION CONTACT: Karen V. Gregory, Secretary, Federal Maritime Commission...

Aging Out in the Queer Community: Silence to Sanctuary to Activism in Faith Communities: A conversation with Barbara Satin.

PubMed

Fredriksen-Goldsen, Karen

2016-01-01

In this article, Generations Guest Editor Karen Fredriksen-Goldsen interviews Barbara Satin, a transgender woman with a national leadership role in the United Church of Christ. Satin addresses the history, challenges, and hopes for LGBT older adults seeking sanctuary in modern faith communities as they age.

Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (78th, Washington, DC, August 9-12, 1995). Qualitative Studies Division.

ERIC Educational Resources Information Center

Association for Education in Journalism and Mass Communication.

The Qualitative Studies section of the proceedings contains the following 14 papers: "'Virtual Anonymity': Online Accountability in Political Bulletin Boards and the Makings of the Virtuous Virtual Journalist" (Jane B. Singer); "The Case of the Mysterious Ritual: 'Murder, She Wrote' and 'Perry Mason'" (Karen E. Riggs);…

Chronicle of Higher Education. Volume 51, Number 31, April 8, 2005

ERIC Educational Resources Information Center

Chronicle of Higher Education, 2005

2005-01-01

"Chronicle of Higher Education" presents an abundant source of news and information for college and university faculty members and administrators. This April 8, 2005 issue of "Chronicle for Higher Education" includes the following articles: (1) "Words Worth Their Weight in Cash" (Markin, Karen); (2) "Diary of a…

Travel in Time: Tradition to Technology. Proceedings of the 1985 ABC International Convention (Chicago, Illinois, October 1985).

ERIC Educational Resources Information Center

Bruno, Sam J., Ed.; Pettit, John D., Jr., Ed.

These conference proceedings contain the following 23 presentations: "Development of a Communication Skill Model Using Interpretive Structural Modeling" (Karen S. Nantz and Linda Gammill); "The Coincidence of Needs: An Inventional Model for Audience Analysis" (Gina Burchard); "A Computer Algorithm for Measuring Readability" (Terry D. Lundgren);…

Information Literacy Assessment

ERIC Educational Resources Information Center

Warmkessel, Marjorie M.

2007-01-01

This article presents an annotated list of seven recent articles on the topic of information literacy assessment. They include: (1) "The Three Arenas of Information Literacy Assessment" (Bonnie Gratch Lindauer); (2) "Testing the Effectiveness of Interactive Multimedia for Library-User Education" (Karen Markey et al.); (3)…

Introducing Internet Services.

ERIC Educational Resources Information Center

Diaz, Karen R.; And Others

1994-01-01

Four articles describe the usefulness of the Internet to reference librarians and discuss Internet search tools: "Getting Started on the Net" (Karen R. Diaz); "Gopher Searching Using VERONICA" (Lousie McGillis); "How to Use VERONICA To Find Information on the Internet" (Jackie Mardikian); and "The Internet…

Overcoming Language and Literacy Barriers: Using Student Response System Technology to Collect Quality Program Evaluation Data from Immigrant Participants

ERIC Educational Resources Information Center

Walker, Susan K.; Mao, Dung

2016-01-01

Student response system technology was employed for parenting education program evaluation data collection with Karen adults. The technology, with translation and use of an interpreter, provided an efficient and secure method that respected oral language and collective learning preferences and accommodated literacy needs. The method was popular…

INTERIOR SECOND FLOOR EAST END LOOKING WEST AT NORTH ROW ...

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

INTERIOR SECOND FLOOR- EAST END LOOKING WEST AT NORTH ROW OF MUSHROOM COLUMNS. - Colt Fire Arms Company, South Armory Building, 36-150 Huyshope Avenue, 17-170 Van Dyke Avenue, 49 Vredendale Avenue, Hartford, Hartford County, CT

INTERIOR FOURTH FLOOR, SOUTH HALF, LOOKING SOUTH. NOTE MUSHROOM COLUMNS ...

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

INTERIOR FOURTH FLOOR, SOUTH HALF, LOOKING SOUTH. NOTE MUSHROOM COLUMNS AND CEILING HAS WOODEN NAILERS. - Colt Fire Arms Company, North Armory, 36-150 Huyshope Avenue, 17-170 Van Dyke Avenue, 49 Vredendale Avenue, Hartford, Hartford County, CT

78 FR 37270 - Qualification of Drivers; Exemption Applications; Vision

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-20

... (IA) Thomas M. Harris (MI) Paul M. Hinkson (TN) Ellie L. Murphree (AL) Michael P. Passmore (FL) Wendell S. Sehen (OH) Gary E. Valentine (OH) Kevin W. Van Arsdol (CO) Charles Van Dyke (WI) Harlon C. Van...

Flexible Models for Learning English Are Needed for Refugee Mothers

ERIC Educational Resources Information Center

Riggs, Elisha; Block, Karen; Gibbs, Lisa; Davis, Elise; Szwarc, Josef; Casey, Sue; Duell-Piening, Philippa; Waters, Elizabeth

2012-01-01

The importance of English language acquisition for resettlement of refugees is well established, particularly as a pathway to education, employment, health and social connections. A qualitative study was conducted in 2011 in Melbourne, Australia utilising focus groups with 87 refugee background women from Karen, Iraqi, Assyrian Chaldean, Lebanese,…

Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (84th, Washington, DC, August 5-8, 2001). Law Division.

ERIC Educational Resources Information Center

Association for Education in Journalism and Mass Communication.

The Law section of the proceedings contains the following 6 selected papers: "Is the Public Interest Meaningless? Levels of Meaning and Ambiguity in the Public Interest Standard" (Philip M. Napoli); "An 'Unholy Alliance': The Law of Media Ride-Alongs" (Karen M. Markin); "Is Internet Service Provider Immunity Growing? An…

Fitness and Health. Beginnings Workshop.

ERIC Educational Resources Information Center

Child Care Information Exchange, 2000

2000-01-01

Presents five articles on children's fitness and health: "Relaxation: Every Child's Right to Simply Be" (Patrice Thomas and Wendy Shepherd); "Infant Massage" (Carolyn Oleson); "Fitness and the Young Child" (James M. Poole); "Partners in Health: Helping Families Advocate for Their Children's Health Care" (Karen Sokal-Gutierrez); and "Preventing…

Considerations of the Social, Individual, and Embodied: A Response to Comments on "Schema Theory Revisited"

ERIC Educational Resources Information Center

McVee, Mary B.; Gavelek, James R.; Dunsmore, Kailonnie L.

2007-01-01

This article presents the authors' response and clarifications to the comments of Margaret E. Gredler and of Karen A. Krasny, Mark Sadoski, and Allan Paivio on their article "Schema Theory Revisited." The authors first respond to Gredler's criticism contending that they "transmogrified" Harre's (1984) "ignominiously named...Vygotsky space" in…

77 FR 16674 - Establishment of the Wisconsin Ledge Viticultural Area

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-22

... allow vintners to better describe the origin of their wines and to allow consumers to better identify wines they may purchase. DATES: Effective Date: April 23, 2012. FOR FURTHER INFORMATION CONTACT: Karen A.... 205(e), authorizes the Secretary of the Treasury to prescribe regulations for the labeling of wine...

Focus on Basics, 1997.

ERIC Educational Resources Information Center

Focus on Basics, 1997

1997-01-01

Together, these four newsletters contain 36 articles devoted to adult literacy research and practice and the relationship between them. The following articles are included: "A Productive Partnership" (Richard J. Murnane, Bob Bickerton); "Welcome to 'Focus on Basics'" (Barbara Garner); "Applying Research on the Last Frontier" (Karen Backlund, Kathy…

Gifted Education Press Quarterly. Volume 10, 1996.

ERIC Educational Resources Information Center

Gifted Education Press Quarterly, 1996

1996-01-01

This set of four newsletters discusses current issues in gifted education. The first issue includes: "The Underserved Young Gifted Child: Status of Programs and Research" (Joan Smutny); "The Home Education Model: An Alternative Program for the Gifted" (Karen Kendig) and "Jonathan Swift (1667-1745): A Need for Gifted…

76 FR 37634 - Revision to the Validated End-User Authorization for CSMC Technologies Corporation in the People...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

...: Karen Nies-Vogel, Chair, End-User Review Committee, Office of the Assistant Secretary, Export... amended the EAR in a final rule on June 19, 2007 (72 FR 33646), creating a new authorization for..., reexported, or transferred (in-country) under a general authorization instead of a license, in conformance...

77 FR 23114 - Addition of Certain Persons on the Entity List: Addition of Persons Acting Contrary to the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-18

... exports, reexports, and transfers (in-country) to entities identified on the Entity List require a license... CONTACT: Karen Nies-Vogel, Chair, End-User Review Committee, Office of the Assistant Secretary, Export...) to entities identified on the Entity List require a license from the Bureau of Industry and Security...

78 FR 69535 - Amendments to Existing Validated End-User Authorizations in the People's Republic of China

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-20

..., add a facility to the list of eligible destinations and two items to the list of eligible items for.... DATES: This rule is effective November 20, 2013. FOR FURTHER INFORMATION CONTACT: Karen Nies-Vogel... may be exported, reexported, or transferred (in-country) under a general authorization instead of a...

Measuring Music Education: A Philosophical Investigation of the Model Cornerstone Assessments

ERIC Educational Resources Information Center

Richerme, Lauren Kapalka

2016-01-01

Despite substantial attention to measurement and assessment in contemporary education and music education policy and practice, the process of measurement has gone largely undiscussed in music education philosophy. Using the work of physicist and philosopher Karen Barad, in this philosophical inquiry, I investigated the nature of measurement in…

Reader's Response: Response to K. Hornsby's "Developing and Assessing Undergraduate Students' Moral Reasoning Skills"

ERIC Educational Resources Information Center

Payne, Carla

2008-01-01

In this brief response, Carla Payne comments on Karen Hornsby's "Developing and Assessing Undergraduate Students' Moral Reasoning Skills" (EJ1137006). Payne agrees with Hornsby's statement that the development of "moral reasoning skills" is a very desirable outcome for an ethics course, yet takes issue with Hornsby not sticking…

The Politics of Teacher Education Reform. The National Commission on Teaching and America's Future. Yearbook of the Politics of Education Association. [Volume 13].

ERIC Educational Resources Information Center

Gallagher, Karen Symms, Ed.; Bailey, Jerry D., Ed.

This book contains a collection of papers on the politics of teacher education reform. The book begins with "Introduction to the Politics of Teacher Preparation Reform" (Karen Symms Gallagher and Jerry D. Bailey). Part 1, "Issues From the National Arena," includes "The Politics of Teacher Education Reform: Strategic…

Culture, Relevance, and Schooling: Exploring Uncommon Ground

ERIC Educational Resources Information Center

Scherff, Lisa, Ed.; Spector, Karen, Ed.

2011-01-01

In "Culture, Relevance, and Schooling: Exploring Uncommon Ground," Lisa Scherff, Karen Spector, and the contributing authors conceive of culturally relevant and critically minded pedagogies in terms of opening up new spatial, discursive, and/or embodied learning terrains. Readers will traverse multiple landscapes and look into a variety of spaces…

Mental Health Issues in Rural Nursing.

ERIC Educational Resources Information Center

Babich, Karen S., Comp.

Five papers cover recent developments in rural mental health nursing. "Rural Mental Health Care: A Survey of the Research" (Karen Babich) chronicles recent interest in understanding the rural population's character and the nature of mental health services needed by and provided to rural America. Lauren Aaronson ("Using Health…

The Role of Schools in Obesity Prevention

ERIC Educational Resources Information Center

Story, Mary; Kaphingst, Karen M.; French, Simone

2006-01-01

Mary Story, Karen Kaphingst, and Simone French argue that U.S. schools offer many opportunities for developing obesity-prevention strategies by providing more nutritious food, offering greater opportunities for physical activity, and providing obesity-related health services. Meals at school are available both through the U.S. Department of…

The Role of Child Care Settings in Obesity Prevention

ERIC Educational Resources Information Center

Story, Mary; Kaphingst, Karen M.; French, Simone

2006-01-01

Mary Story, Karen Kaphingst, and Simone French argue that researchers and policymakers focused on childhood obesity have paid insufficient attention to child care. Although child care settings can be a major force in shaping children's dietary intake, physical activity, and energy balance--and thus in combating the childhood obesity…

Sustaining Professional Learning Communities. The Soul of Educational Leadership Series

ERIC Educational Resources Information Center

Blankstein, Alan M., Ed.; Houston, Paul D., Ed.; Cole, Robert W., Ed.

2007-01-01

The third volume of "The Soul of Educational Leadership" series offers key concepts and strategies for sustaining the critically important work of professional learning communities. With contributions from Shirley Hord, Maurice Elias, Karen Seashore Louis, Andy Hargreaves, and other nationally known educators, this essential reading for all school…

Bridges to the Future: Building Linkages for Institutional Research. North East Association for Institutional Research Annual Conference Proceedings (27th, Pittsburgh, PA, November 4-7, 2000).

ERIC Educational Resources Information Center

North East Association for Institutional Research.

This document contains papers, summaries of panel presentations, and work share meetings from the annual conference of the North East Association for Institutional Research. The papers are: (1) "The Influence of Personality Traits, Pre-College Characteristics, and Co-Curricular Experiences on College Outcomes" (Karen W. Bauer); (2)…

Registering Researchers in Authority Files

ERIC Educational Resources Information Center

Smith-Yoshimura, Karen; Altman, Micah; Conlon, Michael; Cristán, Ana Lupe; Dawson, Laura; Dunham, Joanne; Hickey, Thom; Hook, Daniel; Horstmann, Wolfram; MacEwan, Andrew; Schreur, Philip; Smart, Laura; Wacker, Melanie; Woutersen, Saskia

2014-01-01

Written by OCLC Research Program Officer Karen Smith-Yoshimura and the 13 members of the Registering Researchers in Authority Files Task Group comprised of specialists from the US, UK, and the Netherlands, this report summarizes their research into approaches to providing authoritative researcher identifiers. Registering researchers in some type…

Forum: Cultural Identity and (Dis)Continuities of Children of Immigrant Communities

ERIC Educational Resources Information Center

Obsiye, Mohamed; Cook, Rachel

2016-01-01

Susan Harper's study centres on "funds of knowledge" as a pedagogical resource for the development of a science curriculum, drawing on Karen refugee parents' cultural knowledge and identity. She argues that engagement in this process helps the parent generation of this community to "rebuild their cultural resilience" and cope…

A NOVEL S-ADENOSYL-L-METHIONINE: ARSENIC (III) METHYLTRANSFERASE FROM RAT LIVER CYTOSOL

EPA Science Inventory

A Novel S-Adenosyl-L-methionine: Arsenic(III) Methyltransferase from Rat Liver Cytosol
Shan Lin, Qing Shi, F. Brent Nix, Miroslav Styblo, Melinda A. Beck, Karen M. Herbin-Davis, Larry L. Hall, Josef B. Simeonsson, and David J. Thomas
S-adenosyl-L-methionine (AdoMet): ar...

KSC-2012-4091

NASA Image and Video Library

2012-07-30

CAPE CANAVERAl, Fla. - Karen L. Thompson, chief technologist for Kennedy Space Center, speaks during a visit by Dr. Mason Peck, NASA's chief Technologist, to to Kennedy Space Center's Space Life Sciences Laboratory. Peck toured the lab facility during a visit to the space center. Photo credit: NASA/Frankie Martin

78 FR 25336 - Mississippi Disaster # MS-00066

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-30

... Administrative declaration of a disaster for the State of Mississippi dated 04/18/2013. Incident: Severe Storms and Tornadoes. Incident Period: 04/11/2013 through 04/12/2013. Effective Date: 04/18/2013. Physical... Federal Domestic Assistance Numbers 59002 and 59008) Dated: April 18, 2013. Karen G. Mills, Administrator...

Schools and Staffing Survey: 1994. Papers Presented at the 1994 Meeting of the American Statistical Association. Working Paper Series.

ERIC Educational Resources Information Center

National Center for Education Statistics (ED), Washington, DC.

The 14 papers presented in this proceedings include: (1) "Intersurvey Consistency in School Surveys" (Wray Smith, Al Holt, Steven Kaufman, and Fritz Scheuren); (2) "Estimation Issues Related to the Student Component of the SASS" (Karen Ellen King and Steven Kaufman); (3) "Properties of the Schools and Staffing Survey's…

Collaborative Leadership as a Catalyst for Change

ERIC Educational Resources Information Center

Davenport, Allan; Mattson, Kristen

2018-01-01

In the spring of 2015, Dr. Karen Sullivan, superintendent of Indian Prairie School District 204 in Aurora, Illinois, signed the Alliance for Excellent Education's Future Ready Pledge, "making a firm commitment to implementing meaningful changes toward a digital learning transition that supports teachers, and addresses the district's vision…

Multiculturalism in Developmental Education. CRDEUL Monograph.

ERIC Educational Resources Information Center

Higbee, Jeanne L., Ed.; Lundell, Dana Britt, Ed.; Duranczyk, Irene M., Ed.

This collection of papers is intended to help make connections between multicultural education and developmental education. The papers include an introduction by Jeanne L. Higbee and: "The Centrality of Multiculturalism in Developmental Education" (Karen L. Miksch, Patrick L. Bruch, Jeanne L. Higbee, Rashne R. Jehangir, and Data Britt…

HRD Integrity through Business-Research Partnerships. Keynote Presentation.

ERIC Educational Resources Information Center

1996

This document contains two keynote papers presented at the 1996 conference of the Academy of Human Resource Development (AHRD). "Partnering for Research: The Ford Design Institute/UGA (University of Georgia) Research Project" (Karen E. Watkins, Lewis J. Bellinger) describes the Ford Design Institute's Manager as Instructor project and…

Hydrogeological Studies of Mendhwan Watershed, Ahmadnagar District, Maharashtra, India

NASA Astrophysics Data System (ADS)

Muley, R. B.; Babar, Md.; Kulkarni, P. S.

2011-07-01

The Mendhwan watershed area is a part of chronic drought prone region of Ahmadnagar district of Maharashtra state, India which is considered for the study with reference to hydrogeological characteristics in Deccan basaltic terrain. In order to enhance groundwater availability and to demarcate the area of high groundwater potential, Geoforum, Parbhani Chapter has carried out hydrological investigation of this watershed area. Geologically, the study area belongs to the Deccan trap basalts of late Cretaceous to early Eocene period. The entire study area consists of thin irregular vesicular-amygdaloidal basalt flows also known as compound pahoehoe flows. The area is traversed by two prominent dykes, which are almost perpendicular to each other. In most of the southern part of the area, amygdaloidal basalt is exposed at the surface. The fresh amygdaloidal basalt flow is free from joints and occurs as homogeneous watertight mass. As dykes are jointed, they provide favorable conditions for percolation and ground water potential of this area is found to be satisfactory. It was observed that in Mendhwan area a large number of water conservation structures have been constructed across the streams. Incidentally groundwater potential shows notable increase only in those localities where the structures had been constructed on the dyke rock. The result of the study is found to be very much beneficial to the rural populace of this draught prone area so as to plan the optimum utilization of this precious natural resource.

Relation between alternating open/closed-conduit conditions and deformation patterns: An example from the Somma-Vesuvius volcano (southern Italy)

NASA Astrophysics Data System (ADS)

Tramparulo, F. D. A.; Vitale, S.; Isaia, R.; Tadini, A.; Bisson, M.; Prinzi, E. P.

2018-07-01

We present the results of a meso-scale systematic structural analysis of fractures, faults and dykes exposed at the Somma-Vesuvius volcano (southern Italy). Observed fractures include: (i) radial and tangential (with respect the caldera axis), sub-metric to metric joints associated with the edifice load and volcano-tectonic activity (i.e. inflation, deflation and caldera collapse stages) and (ii) decameter-scale fractures related to volcano flank instabilities. For the Somma-Vesuvius volcano, preexisting radial joints were commonly reactivated as transfer faults during the caldera formation, allowing different blocks to move toward the center of the collapsing area. Dykes occur with different geometries, including en-echelon structures bounding structural depressions. The orientation analysis of all structures indicates that they are preferentially oriented. Furthermore, we provide a morphological lineament analysis using high-resolution Digital Terrain Models of Somma-Vesuvius. Azimuth and spatial distribution of dykes and morphological lineaments were analyzed for comparison with the old Somma Crater and Gran Cono axes, respectively. Results highlight the overprinting of radial and clustered strain patterns recorded in different volcano-tectonic evolution stages. We suggest a possible deformation evolution model in which structures develop along either radial or preferential trends, highlighting different volcanic conditions: (i) where radial patterns occur, the structures developed during volcanic inflation cycles with a closed magmatic conduit condition whereas (ii) clustered patterns are probably associated with a regional strain field that overcomes the local deformation field, a situation typical in the case of open-conduit activity.

Characterisation of the hydrogeology of the Augustus River catchment, Western Australia

NASA Astrophysics Data System (ADS)

Wilkes, Shane M.; Clement, T. Prabhakar; Otto, Claus J.

Understanding the hydrogeology of weathered rock catchments is integral for the management of various problems related to increased salinity within the many towns of Western Australia. This paper presents the results of site characterisation investigations aimed at improving the overall understanding of the hydrogeology of the southern portion of the Augustus River catchment, an example of a weathered rock catchment. Site data have highlighted the presence of both porous media aquifers within the weathered profile and fractured rock aquifers within the basement rocks. Geophysical airborne surveys and other drilling data have identified a large number of dolerite dykes which crosscut the site. Fractured quartz veins have been found along the margins of these dolerite dykes. Detailed groundwater-level measurements and barometric efficiency estimates indicate that these dolerite dykes and fractured quartz veins are affecting groundwater flow directions, promoting a strong hydraulic connection between all aquifers, and also influencing recharge mechanisms. The hydrogeological significance of the dolerite dykes and fractured quartz veins has been assessed using a combination of high-frequency groundwater-level measurements (30-min sampling interval), rainfall measurements (5-min sampling interval) and barometric pressure fluctuations (30-min sampling interval). A conceptual model was developed for describing various hydrogeological features of the study area. The model indicates that fractured quartz veins along the margins of dolerite dykes are an important component of the hydrogeology of the weathered rock catchments. Comprendre l'hydrogéologie des bassins en roches altérées est essentiel pour la gestion de différents problèmes liés à l'augmentation de la salinité dans de nombreuses villes d'Australie occidentale. Cet article présente les résultats d'études de caractérisation de sites conduites pour améliorer la compréhension de l'hydrogéologie de la

CRADAs: They're Not Just for NCI Anymore | Poster

Cancer.gov

By Karen Surabian, Thomas Stackhouse, and Jeffrey Thomas, Contributing Writers, and Bruce Crise, Guest Writer Advancing scientific discovery is increasingly dependent on diverse and innovative partnerships, and the Cooperative Research and Development Agreement (CRADA) is an essential tool for establishing partnerships. CRADAs allow a federal laboratory to enter into

The Materiality of Fieldwork: An Ontology of Feminist Becoming

ERIC Educational Resources Information Center

Childers, Sara M.

2013-01-01

Through the materiality of fieldwork at a high-achieving high-poverty high school, I discuss how the collision between practices of feminist methodology and the materiality of fieldwork forced me to rethink the "feminist" in feminist research. Using the work of Karen Barad, this material-discursive account of methodology as ontology…

76 FR 32990 - Workforce Investment Act of 1998 (WIA); Notice of Incentive Funding Availability for Program Year...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-07

... portion and Adult Education and Family Literacy Act of the incentives review, respectively; the notice has been updated to include this appendix. Please note that no information has changed on the notice, nor..., 2011. FOR INFORMATION CONTACT: Karen A. Staha or Luke Murren, U.S. Department of Labor, Employment and...

76 FR 64421 - Senior Executive Service: Performance Review Board Members

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-18

... Financial Law and Lender Oversight 4. Pravina Raghavan, District Director, New York District Office 5. Tong Qin, Deputy Chief Financial Officer 6. Steven Smits, Associate Administrator for Capital Access 7. Jonathan Swain, Chief of Staff Karen G. Mills, Administrator. [FR Doc. 2011-26833 Filed 10-17-11; 8:45 am...

Vice President Pence Tours Jet Propulsion Laboratory

NASA Image and Video Library

2018-04-28

U.S. Vice President Mike Pence, 3rd from left, his wife Karen, and their daughter Charlotte meet with JPL Director Michael Watkins, and Mars Curiosity Mission ACE Walt Hoffman, right, during a tour of NASA's Jet Propulsion Laboratory, Saturday, April 28, 2018 in Pasadena, California. Photo Credit: (NASA/Bill Ingalls)

Why Do Bees Sting? Reflecting on Talk in Science Lessons

ERIC Educational Resources Information Center

Boctor, Sonia; Rowell, Patricia M.

2004-01-01

Learning science in a meaningful way involves more than doing a series of activities directed towards anticipated outcomes. Learning science entails teacher and children talking together as "co-constructors" of knowledge (Barnes, 1976). Karen Gallas (1995) has described her long-term observations of the kinds of talk which contribute to…

Learning from Leadership: Investigating the Links to Improved Student Learning. The Informed Educator Series

ERIC Educational Resources Information Center

Wahlstrom, Kyla L.; Louis, Karen Seashore; Leithwood, Kenneth; Anderson, Stephen E.

2010-01-01

In a recent 334-page report, "Investigating the Links to Improved Student Learning," authors Kyla Walstrom, Karen Seashore Louis, Kenneth Leithwood, and Stephen Anderson discuss findings from the Learning from Leadership study. This study was designed to identify and describe successful educational leadership and to explain how such leadership at…

Sally Ride Tribute

NASA Image and Video Library

2013-05-20

Co-Founder of Sally Ride Science Karen Flammer talks about educational outreach programs for NASA, ISS EarthKAM, and Grail MoonKAM during the National Tribute to Sally Ride at the John F. Kennedy Center for the Performing Arts, Monday, May 20, 2013 in Washington. Photo Credit: (NASA/Bill Ingalls)

A Guide to Using State Longitudinal Data for Applied Research. NCEE 2015-4013

ERIC Educational Resources Information Center

Levesque, Karen; Fitzgerald, Robert; Pfeiffer, Jay

2015-01-01

State longitudinal data systems (SLDSs) promise a rich source of data for education research. SLDSs contain statewide student data that can be linked over time and to additional data sources for education management, reporting, improvement, and research, and ultimately for informing education policy and practice. Authored by Karen Levesque, Robert…

Economic Education Experiences of Enterprising Teachers. Volume 31.

ERIC Educational Resources Information Center

Nappi, Andrew T., Ed.

This book describes award-winning teacher-developed projects and courses in economics. The reports are condensed versions of the original projects and are divided into grade levels. Primary Level includes: "Primary Pickle People Packed a Peck of Pickle Economics" (Karen L. Cragg; Katherine J. Van Horn); "Fabulous Economics" (Elizabeth B.…

Preparing the Next Generation of Educators for Democracy

ERIC Educational Resources Information Center

Embry-Jenlink, Karen

2018-01-01

In the keynote address of the 42nd annual meeting of the Southeastern Regional Educators Association (SRATE), ATE President Karen Embry-Jenlink examines the critical role of teacher educators in preparing the next generation of citizens and leaders to sustain democracy. Drawing from historic and current events and personal experience,…

Library Programs for Teens: Mystery Theater. VOYA Guides

ERIC Educational Resources Information Center

Siwak, Karen J.

2010-01-01

It's no mystery that fun and exciting programs bring teens into the library. Theater programs provide a venue for teens to express themselves creatively, encourage their participation in library programming, and offer them the opportunity for lively interaction with peers and adults. In "Library Programs for Teens: Mystery Theater," Karen Siwak…

Health Occupations Education. Biennial National Health Occupations Research Conference Proceedings. (5th, Nashville, Tennessee, December 1, 1993).

ERIC Educational Resources Information Center

Rzonca, Chet, Ed.

These proceedings include the agenda of the conference, a list of its cosponsors, and the texts of the following six papers presented at the conference: "Hepatitis Vaccine: Are Health Occupations Education Students Protected?" (Cynthia Chappelka); "Integrated Academics: An HOE Model" (Karen E. Gable, Beverly Ransdell); "The Ability of Work Related…

76 FR 63184 - Addition of Certain Persons on the Entity List; Implementation of Entity List Annual Review...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-12

... as a result of requests for removal submitted by each of these three persons, a review of information...-country) to entities identified on the Entity List require a license from the Bureau of Industry and... effective October 12, 2011. FOR FURTHER INFORMATION CONTACT: Karen Nies-Vogel, Chair, End-User Review...

75 FR 67029 - Amendment to Existing Validated End-User Authorization in the People's Republic of China...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-01

... the PRC due to a material change at SMIC. This amendment is not the result of prohibited activities by... are welcome on a continuing basis. ADDRESSES: You may submit comments, identified by RIN 0694-AF02 by... the three methods outlined above. FOR FURTHER INFORMATION CONTACT: Karen Nies-Vogel, Chairman, End...

78 FR 54752 - Addition and Revision to the List of Validated End-Users in the People's Republic of China

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-06

... (Dalian) Ltd. (Intel Dalian) as a VEU. With this rule, exports, reexports and transfers (in-country) of... FURTHER INFORMATION CONTACT: Karen Nies-Vogel, Chair, End-User Review Committee, Bureau of Industry and...) under a general authorization instead of a license. The names of the VEUs, as well as the dates they...

76 FR 2802 - Additions and Revisions to the List of Validated End-Users in the People's Republic of China...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-18

... formal comment period, public comments on this regulation are welcome on a continuing basis. ADDRESSES... INFORMATION CONTACT: Karen Nies-Vogel, Chair, End-User Review Committee, Office of the Assistant Secretary... amended the EAR in a final rule on June 19, 2007 (72 FR 33646) by creating a new authorization for...

Working To Learn: Transforming Learning in the Workplace.

ERIC Educational Resources Information Center

Evans, Karen, Ed.; Hodkinson, Phil, Ed.; Unwin, Lorna, Ed.

This book contains 13 papers on transformations in the nature of work that affect the learning and skill requirements of jobs and individuals and ways those requirements can be met. The following papers are included: "The Significance of Workplace Learning for a 'Learning Society'" (Karen Evans, Helen Rainbird); "Learning Careers:…

Making Biology Relevant to Undergraduates

ERIC Educational Resources Information Center

Musante, Susan

2012-01-01

This article features Science Education for New Civic Engagements and Responsibilities (SENCER; www.sencer.net) Summer Institute. The SENCER program, which began formally in 2001, was the vision of David Burns; Karen Oates, currently Peterson Family Dean of Arts and Sciences at Worcester Polytechnic Institute; and Ric Wiebl, currently director of…

Working Papers in Art Education, 1988.

ERIC Educational Resources Information Center

Zurmuehlen, Marilyn, Ed.

1988-01-01

This publication presents manuscripts and research reports by graduate students. Accompanying papers from their mentors establish a context for the student papers. In this volume the works are organized by sponsoring university. Student papers presented are: (1) "A Naturalistic Study of Art Choices in a Preschool Setting" (Karen Thomas);…

A Collectibles Project: Engaging Students in Authentic Multimodal Research and Writing

ERIC Educational Resources Information Center

Moynihan, Karen E.

2007-01-01

High school teacher Karen E. Moynihan creates a multimodal project inspired by the creative nonfiction style of "The Orchid Thief" by Susan Orlean. Students choose a collectible item and immerse themselves in the subculture of the collectors. The project includes participation in library and field research, interviews, photography and graphic…

The Future Is Now: The Role of Institutional Research in Campus Transformation: Proceedings of the Annual Conference of the North East Association for Institutional Research (25th, Philadelphia, Pennsylvania, November 14-17, 1998).

ERIC Educational Resources Information Center

North East Association for Institutional Research.

This proceedings document is comprised of the 17 papers, panel presentations, and work shares presented at a 1998 conference on institutional research. The papers are: (1) "Description of the UDAES Project: A Study of Undergraduate Academic Experiences" (Karen W. Bauer); (2) "Transforming Your Campus: Mixed Methodology in Institutional Research"…

The Social and Emotional Development of Gifted Children: What Do We Know?

ERIC Educational Resources Information Center

Neihart, Maureen, Ed.; Reis, Sally M., Ed.; Robinson, Nancy M., Ed.; Moon, Sidney M., Ed.

This text on the social and emotional development of gifted children includes the following 24 papers: (1) "Effects of Acceleration on Gifted Learners" (Karen Rogers); (2) "Peer Pressures and Social Acceptance of Gifted Students" (Sylvia Rimm); (3) "Social and Emotional Issues for Exceptional Intellectually Gifted Students" (Miraca Gross); (4)…

Communication and Mental Health: Psychiatric Forerunners.

ERIC Educational Resources Information Center

Brooks, Deems M.

The connections between human communication and mental health were first noted 50 to 60 years ago by such early psychiatrists as Alfred Adler, Harry Stack Sullivan, and Karen Horney. They were concerned with understanding those communication processes and skills that make for effective, fully functioning human beings. Adler emphasized faulty…

76 FR 22674 - Manufacturing Extension Partnership Advisory Board

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-22

... Open Meeting. SUMMARY: NIST announces that the Manufacturing Extension Partnership (MEP) Advisory Board, National Institute of Standards and Technology (NIST) will hold an open meeting on Sunday, May 15, [email protected]nist.gov or 301-975-5614) no later than May 2, 2011. FOR FURTHER INFORMATION CONTACT: Karen Lellock...

77 FR 2606 - Unblocking of Specially Designated Nationals and Blocked Persons Pursuant to Executive Order 12978

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-18

.... RENTERIA CAICEDO, Beatriz Eugenia, c/o INVERSIONES AGROINDUSTRIALES DEL OCCIDENTE LTDA., Bogota, Colombia... ILOVIN S.A., Bogota, Colombia; c/o INVERSIONES DEL PRADO ABDALA SAIEH Y CIA. S.C.A., Barranquilla...., Bogota, Colombia; c/o INVERSIONES DEL PRADO ABDALA SAIEH Y CIA. S.C.A., Barranquilla, Colombia; c/o KAREN...

"Effects Of" and "Effects With" Captions: How Exactly Does Watching a TV Programme with Same-Language Subtitles Make a Difference to Language Learners?

ERIC Educational Resources Information Center

Vanderplank, Robert

2016-01-01

Ever since Karen Price's ground-breaking work in 1983, we have known that same-language subtitles (captions) primarily intended for the deaf and hearing-impaired can provide access to foreign language films and TV programmes which would otherwise be virtually incomprehensible to non-native-speaker viewers. Since then, researchers have steadily…

The Next Wave of HIV/AIDS: Nigeria, Ethiopia, Russia, India, and China

DTIC Science & Technology

2002-09-01

Prepared under the auspices of David F. Gordon, formerly National Intelligence Officer for Economics and Global Issues . Additional...Intelligence Officer for Economics and Global Issues . September 2002 Scope Note This Intelligence Community Assessment (ICA...East Asia Arthur Brown Economics & Global Issues Karen Monaghan Acting Europe Barry F. Lowenkron Latin America Fulton

Dykes and tykes: a virtual lesbian parenting community.

PubMed

Lev, Arlene Istar; Dean, Gwendolyn; DeFilippis, Lauren; Evernham, Kim; McLaughlin, Larin; Phillips, Cynthia

2005-01-01

This article is a collaborative project by six members of an Internet community of lesbian mothers called MOMS. MOMS is a diverse community of lesbian mothers that is inclusive of bisexual and transgender women, as well those planning to become parents. The article outlines the history of the group and how the moderators have created an environment that encourages diversity. Members of the MOMS community differ in age, race, ethnicity, and nationality, as well as political, religious, and social expressions. Additionally, they became parents in diverse ways and parent children in distinct and often disparate styles. Nonetheless, MOMS is a high-volume list with a large membership that remains a close-knit and intimate discussion group. This article outlines some of the discussion topics common on the MOMS list. Some of these are particular to parenting, and others involve a broad spectrum of subjects including racism, butch/femme dynamics, vegetarianism, circumcision, breast versus bottle feeding, and transgender politics. To subscribe to the MOMS list, send an e-mail message to majordomo@groups.queernet.org. Write "subscribe moms" in the body of the e-mail, without quotation marks.

Queerer than queer: reflections of a Kike dyke.

PubMed

Goldflam, A

1999-01-01

In this article the author, a Jewish lesbian academic, reflects on the positive and negative aspects of her dual identity and explores her feelings of exclusion from "in groups" in a range of settings. Annie Goldflam carries a legacy of fear from stories of medieval "witch" burnings and drownings and the twentieth century Jewish Holocaust, which she reflects on to compare the nature of anti-semitism and lesbophobia, considering the options of hiding from racist and homophobic forms of oppression or confronting them. She has chosen to confront, be "out" and politically active.

Contact metamorphism, partial melting and fluid flow in the granitic footwall of the South Kawishiwi Intrusion, Duluth Complex, USA

NASA Astrophysics Data System (ADS)

Benko, Z.; Mogessie, A.; Molnar, F.; Severson, M.; Hauck, S.; Lechler, P.; Arehart, G.

2012-04-01

The footwall of the South Kawishiwi Intrusion (SKI) a part of the Mesoproterozoic (1.1 Ga) Duluth Complex consists of Archean granite-gneiss, diorite, granodiorite (Giant Range Batholith), thin condensed sequences of Paleoproterozoic shale (Virginia Fm.), as well as banded iron formation (Biwabik Iron Fm). Detailed (re)logging and petrographic analysis of granitic footwall rocks in the NM-57 drillhole from the Dunka Pit area has been performed to understand metamorphic processes, partial melting, deformation and geochemical characteristics of de-volatilization or influx of fluids. In the studied drillhole the footwall consists of foliated metagranite that is intersected by mafic (dioritic) dykes of older age than the SKI. In the proximal contact zones, in the mafic dykes, the orthopyroxene+clinopyroxene+plagioclase+quartz+Fe-Ti-oxide+hornblende±biotite porphyroblasts embedded in a plagioclase+K-feldspar+orthopyroxene+apatite matrix indicate pyroxene-hornfels facies conditions. Migmatitization is revealed by the euhedral crystal faces of plagioclase and pyroxene against anhedral quartz crystals in the in-situ leucosome and by the presence of abundant in-source plagioclase±biotite leucosome veinlets. Amphibole in the melanosome of mafic dykes was formed with breakdown of biotite and implies addition of H2O to the system during partial melting. Towards the deeper zones, the partially melted metatexite-granite can be characterized by K-feldspar+plagioclase+quartz+ortho/clinopyroxene+biotite+Fe-Ti-oxide+apatite mineral assemblage. The felsic veins with either pegmatitic or aplititic textures display sharp contact both to the granite and the mafic veins. They are characterized by K-feldspar+quartz±plagioclase±muscovite mineral assemblage. Sporadic occurrence of muscovite suggest local fluid saturated conditions. Emplacement of gabbroic rocks of the SKI generated intense shear in some zones of the granitic footwall resulting in formation of biotite-rich mylonites with

Study of the deformation in Central Afar using InSAR NSBAS chain

NASA Astrophysics Data System (ADS)

Deprez, A.; Doubre, C.; Grandin, R.; Saad, I.; Masson, F.; Socquet, A.

2013-12-01

The Afar Depression (East Africa) connects all three continental plates of Arabia, Somalia and Nubia plates. For over 20 Ma, the divergent motion of these plates has led to the formation of large normal faults building tall scarps between the high plateaus and the depression, and the development of large basins and an incipient seafloor spreading along a series of active volcano-tectonic rift segments within the depression. The space-time evolution of the active surface deformation over the whole Afar region remains uncertain. Previous tectonic and geodetic studies confirm that a large part of the current deformation is concentrated along these segments. However, the amount of extension accommodated by other non-volcanic basins and normal faulting remains unclear, despite significant micro-seismic activity. Due to the active volcanism, large transient displacements related to dyking sequence, notably in the Manda Hararo rift (2005-2010), increase the difficulty to characterize the deformation field over simple time and space scales. In this study, we attempt to obtain a complete inventory of the deformation within the whole Afar Depression and to understand the associated phenomena, which occurred in this singular tectonic environment. We study in particular, the behavior of the structures activated during the post-dyking stage of the rift segments. For this purpose, we conduct a careful processing of a large set of SAR ENVISAT images over the 2004-2010 period, we also use previous InSAR results and GPS data from permanent stations and from campaigns conducted in 1999, 2003, 2010, 2012 within a GPS network particularly dense along the Asal-Ghoubbet segment. In one hand, in the western part of Afar, the far-field response of the 2005-2010 dyke sequence appears to be the dominant surface motion on the mean velocity field. In an other hand, more eastward across the Asal-Ghoubbet rift, strong gradients of deformation are observed. The time series analysis of both In

Experimental approach to form anorthositic melts: phase relations in the system CaAl2Si2O8 - CaMgSi2O6 - Mg2SiO4 at 6 wt.% H2O

NASA Astrophysics Data System (ADS)

Zirner, Aurelia Lucretia Katharina; Ballhaus, Chris; Fonseca, Raúl; Müncker, Carsten

2014-05-01

Massive anorthosite dykes are documented for the first time from the Limassol Forest Complex (LFC) of Cyprus, the LFC being a deformed equivalent of the Troodos ultramafic massif. Both the Troodos and LFC complexes are part of the Tethyan realm consisting of Cretaceous oceanic crust that formed within a backarc basin 90 Ma ago and was obduced during late Miocene. From crosscutting relations with the sheeted dyke complex, it follows that the anorthosites belong to one of the latest magmatic events on Cyprus. In hand specimen, the rocks appear massive and unaltered, although in thin section magmatic plagioclase (An93) is partially replaced by albite and thomsonite (zeolite). Where magmatic textures are preserved, plagioclase forms cm-sized, acicular, radially arranged crystal aggregates that remind of spinifex textures. Six major types of anorthosite occurrences have previously been described, none of them matching with the above described anorthosite dykes [1]. The origin of these anorthosite dykes remains poorly understood. Even though they occur as intrusive dykes, it is evident that they cannot represent liquidus compositions, at least under dry conditions. Whole-sale melting of pure An93 would require temperatures in excess of 1450 °C, which is a quite unrealistic temperature of the modern Earth's crust. The working hypothesis is that boninitic melts with approximately 4 wt.% H2O, as found in the cyprian upper pillow lavas (UPL), could produce such rocks by olivine-pyroxene fractionation. Indeed, experiments indicate that such lithologies can be generated by medium-pressure fractional crystallization of hydrous basaltic melts followed by decompression-degassing. High pH2O stabilizes olivine but tends to suppress plagioclase as the highest polymerized phase. Hence the An component is accumulated in the (late-stage) melt. When such a system experiences sudden decompression, the aqueous phase will exsolve and will trigger massive precipitation of anorthite

Geophysical Survey of the 1978 Seismo-volcanic Crisis in the Asal-Ghoubbet Rift (Afar Depression, Djibouti) and the Post-rifting Deformations

NASA Astrophysics Data System (ADS)

Doubre, C.; Ruegg, J.; de Chabalier, J.; Vigny, C.; Jacques, E.

2006-12-01

In November 1978, a seismo-volcanic crisis occurred in the Asal-Ghoubbet Rift, which is located at the western termination of the oceanic Aden Ridge propagating inland into the Afar Depression and accommodates a large part of the divergent motion of the Arabia and Somalia plates. This episode offered the opportunity to study the rifting process controlling the evolution of a sub-aerial opening segment at the transition from continental break-up to oceanic spreading. This major crustal spreading episode started with two major earthquakes in the subaerial part of the rift (mb=5.3 and 5.0) and was followed by the week-long, basaltic fissure eruption of the Ardukoba at the western tip of the central volcanic chain. The geophysical survey carried out for the crisis was possible by means of the Arta Observatory in Djibouti within the framework of field surveys financed by the French agency CNRS-INSU. This allowed the measurements of the surface breaks (dry open fissures up to 100 m, normal fault throws up to 80 cm), the crustal deformation by geodetic networks and leveling (up to 2m of horizontal widening, 70 cm of inner-floor subsidence), and the evolution of the seismic activity (eastward migration along the Aden Ridge) associated with this rifting event. Elastic modeling shows that both the deformation pattern and the seismic activity can be explained by the aseismic intrusion of two dykes below the rift inner-floor. Subsequently, a continuous geodetic and seismic monitoring has been maintained and shows that the post-dyke injection evolution of the rift is dominated by two distinct periods. During the six first years (1979-1986), high rates of horizontal opening and slip of creeping normal faults accommodate the subsidence of the inner-floor surrimposed to the development of a 25 km-wide uplift. Since 1986-87, the strain rates have decreased and currently reach values consistent with long-term velocities deduced from morpho-tectonic studies. The evolution of the

Thirty-Five Years of Studying Work and Family

ERIC Educational Resources Information Center

Brett, Jeanne M.

2011-01-01

The author and Karen Gyllstrom began working on the study that resulted in the highly cited article entitled, "Working Men and Women: Inter-and Intra-role Conflict" (Herman & Gyllstrom, "Psychology of Women Quarterly" 1977) probably more for personal than professional reasons. The study was based on Gyllstrom's master's thesis. The focus of…