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Sample records for dyke karen woodfork

  1. a Few Lines about Karen

    NASA Astrophysics Data System (ADS)

    Smorodinskaya, Noemi

    2013-06-01

    Karen had tons of amazing students, and it's unfortunate that they could not contribute to this collection. They would have a lot of marvelous stories to tell, since they spent so many days and nights at Karen's house, enjoying Bella Artemievna's hospitality and kindness. Karen was a difficult person, with many eccentricities, but at the same time he was very kind and forgiving. When people he knew had troubles, he always did whatever he could to help them. I should add, however, that due to the many tragedies he had experienced in his family life, Karen's threshold for what counted as troubles was unusually high, and what others perceived as major problems struck him as the minor complications of everyday life...

  2. Karen Avetovich Ter-Martirosyan

    NASA Astrophysics Data System (ADS)

    Shifman, M.

    2013-06-01

    One can say that Karen Avetovich Ter-Martirosyan was one of the stars in the brilliant constellation of theoretical physicists dating back to the golden era of Soviet physics: a disciple of Yakov Frenkel and Lev Landau, he was one of the creators of the theory of (soft) strong interactions at high energies...

  3. Talking about Books: Karen Hesse.

    ERIC Educational Resources Information Center

    Beck, Cathy; Gwyn, Linda; Koblitz, Dick; O'Connor, Anne; Pierce, Kathryn Mitchell; Wolf, Susan

    1999-01-01

    Presents an interview with Karen Hesse, author of 12 books of fiction for young, middle, and older readers, and winner of the 1998 Newbery Award. Offers an overview of Hesse's books, organized into picture books, transition chapter books, and novels. Presents a discussion of the themes found in her books, highlighting children's discussion…

  4. An Interview with Karen Glover

    ERIC Educational Resources Information Center

    Power, June

    2011-01-01

    This article presents an interview with Karen Glover of Georgia Tech, a key person behind the planning of the Access Services Conference held last fall, and now going into its second year. Glover started working in libraries as a part-time library assistant at her local public library during her high school years. She later became a Circulation…

  5. Karen Hesse: The Rest Is History

    ERIC Educational Resources Information Center

    Pierpont, Katherine

    2004-01-01

    This article presents a profile of Newbery Award-winning author Karen Hesse, who is best known for her knack for recovering the little-known stories of the past and making them resonate once again in her books. As a meticulous researcher and lover of things from the past, some of Karen Hesse's most well-loved stories have tugged at her sleeve (and…

  6. 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.

  7. Speaking Personally--With Karen Cator

    ERIC Educational Resources Information Center

    American Journal of Distance Education, 2010

    2010-01-01

    This article presents an interview by Gary E. Miller, executive director emeritus of Penn State World Campus, the online distance education campus of The Pennsylvania State University, with Karen Cator, director of the Office of Educational Technology in the United States Department of Education. She brings to the position a mix of corporate and…

  8. Karen Smith: Language Arts Educator of the Year

    ERIC Educational Resources Information Center

    Hudelson, Sarah

    2009-01-01

    This article honors Karen Smith, who has been given NCTE's Outstanding Educator in the English Language Arts award for 2009. Through the voices of many colleagues and former students, the article celebrates Karen as a teacher, learner, mentor, collaborator, scholar, storyteller, and visionary thinker and doer.

  9. Keystone Characteristics That Support Cultural Resilience in Karen Refugee Parents

    ERIC Educational Resources Information Center

    Harper, Susan G.

    2016-01-01

    This participatory action research study used the conceptual framework of social--ecological resilience to explore how Karen (pronounced Ka·rén) refugee parents re-construct cultural resilience in resettlement. The funds of knowledge approach helped to define essential knowledge used by Karen parents within their own community. Framing this study…

  10. Magma deformation and emplacement in rhyolitic dykes

    NASA Astrophysics Data System (ADS)

    McGowan, Ellen; Tuffen, Hugh; James, Mike; Wynn, Peter

    2016-04-01

    Silicic eruption mechanisms are determined by the rheological and degassing behaviour of highly-viscous magma ascending within shallow dykes and conduits. However, we have little knowledge of how magmatic behaviour shifts during eruptions as dykes and conduits evolve. To address this we have analysed the micro- to macro-scale textures in shallow, dissected rhyolitic dykes at the Tertiary Húsafell central volcano in west Iceland. Dyke intrusion at ~3 Ma was associated with the emplacement of subaerial rhyolitic pyroclastic deposits following caldera formation[1]. The dykes are dissected to ~500 m depth, 2-3 m wide, and crop out in two stream valleys with 5-30 m-long exposures. Dykes intrude diverse country rock types, including a welded ignimbrite, basaltic lavas, and glacial conglomerate. Each of the six studied dykes is broadly similar, exhibiting obsidian margins and microcrystalline cores. Dykes within pre-fractured lava are surrounded by external tuffisite vein networks, which are absent from dykes within conglomerate, whereas dykes failed to penetrate the ignimbrite. Obsidian at dyke margins comprises layers of discrete colour. These display dramatic thickness variations and collapsed bubble structures, and are locally separated by zones of welded, brecciated and flow-banded obsidian. We use textural associations to present a detailed model of dyke emplacement and evolution. Dykes initially propagated with the passage of fragmented, gas-charged magma and generation of external tuffisite veins, whose distribution was strongly influenced by pre-existing fractures in the country rock. External tuffisites retained permeability throughout dyke emplacement due to their high lithic content. The geochemically homogenous dykes then evolved via incremental magma emplacement, with shear deformation localised along emplacement boundary layers. Shear zones migrated between different boundary layers, and bubble deformation promoted magma mobility. Brittle

  11. Keystone characteristics that support cultural resilience in Karen refugee parents

    NASA Astrophysics Data System (ADS)

    Harper, Susan G.

    2016-12-01

    This participatory action research study used the conceptual framework of social-ecological resilience to explore how Karen (pronounced Ka·rén) refugee parents re-construct cultural resilience in resettlement. The funds of knowledge approach helped to define essential knowledge used by Karen parents within their own community. Framing this study around the concept of resilience situated it within an emancipatory paradigm: refugee parents were actors choosing their own cultural identity and making decisions about what cultural knowledge was important for the science education of their children. Sustainability science with its capacity to absorb indigenous knowledge as legitimate scientific knowledge offered a critical platform for reconciling Karen knowledge with scientific knowledge for science education. Photovoice, participant observation, and semi-structured interviews were used to create visual and written narrative portraits of Karen parents. Narrative analysis revealed that Karen parents had constructed a counter-narrative in Burma and Thailand that enabled them to resist assimilation into the dominant ethnic culture; by contrast, their narrative of life in resettlement in the U.S. focused on the potential for self-determination. Keystone characteristics that contributed to cultural resilience were identified to be the community garden and education as a gateway to a transformed future. Anchored in a cultural tradition of farming, these Karen parents gained perspective and comfort in continuity and the potential of self-determination rooted in the land. Therefore, a cross-cultural learning community for Karen elementary school students that incorporates the Karen language and Karen self-sustaining knowledge of horticulture would be an appropriate venue for building a climate of reciprocity for science learning.

  12. Caring for the Karen. A newly arrived refugee group.

    PubMed

    Power, David V; Moody, Emily; Trussell, Kristi; O'Fallon, Ann; Chute, Sara; Kyaw, Merdin; Letts, James; Mamo, Blain

    2010-04-01

    Since 2004, Minnesota has seen an influx of refugees from Burma. Many of these newcomers came from the Karen state and spent time in refugee camps in Thailand before resettling in the United States. To better understand the health needs of this population, the authors of this article conducted chart reviews at a St. Paul family medicine clinic that serves a number of Karen refugees and reviewed formal data from the Minnesota Department of Health's Refugee Health Program. Here, they briefly describe this community, the cultural issues that could affect health care providers' ability to care for Karen patients, and the health concerns of these refugees.

  13. Dyke belt in North Western margin of Siberian platform

    NASA Astrophysics Data System (ADS)

    Ryabov, Victor

    2015-04-01

    The Early Triassic dyke swarm belt is strengthening at about 500 km (50-60 km width) along the northern margin of Siberian platform. Its locations is limited from the north by rift structure of the Yenisei-Khatanga trough, and from the south by Kystyktah-Ayan-Ambardah uprise. From west to east dyke belt is crossing Norilsk, Kamensky and Maimecha-Kotuiskaya province. In this direction the composition of dykes changing from basic rthrough alkali-basic to alkali-ultramafic varieties. The sickness of dykes varies from 0,5-10m up to 90 m and length - from 5-15 m to 140 km. The orientation of the bulk of dykes coincides with the direction of the major structural and tectonic lineaments of the region. Dykes are often refer to the fault planes. The composition of dykes may vary along the stretches. The density of hundreds of basaltic dykes and small intrusions in the dyke swarms is not permanent and sometimes essentially uneven. They form a compact dyke swarms of dykes, stocks and sub layering bodies veins. In dyke package on Huor-Uyallah river here are 20 subparallel dykes of different chemical composition at a distance of 2 km Lack of the evidence of the dykes crossing allows to assume their formation during the same magmatic cycle. Dykes cross cut through the entire incision of basaltic plateau. They did not created the flow effusions and refer to the final stage trap magmatism. Ar/Ar age of the youngest dykes in the province Kamenska 238-247 Ma. the age of lamproite dyke in Norilsk province is 235 Ma. Dykes are represented by dolerites trachydolerites, syenites, minettes, lamprophyres (camptonite, spessartite, vosgesite), avgitites, melanephelinite, alnoites, limburgites alkaline picrites, meimechites. Their content vary widely: SiO2 - 35,7-62,6; TiO2- 0,4-7,5; Al2O3- 4,4-17,5; Fe2O3- 4,6-20,6; MnO- 0,08-0,44; MgO- 0,8-31,5; CaO- 0,7-15,4; Na2O- 0,01-6,5; K2O 0,8-5,3 wt.%; P2O5 0,1-1,2 wt.%. The h Bolsheavamskaya volcanic basin in Kamensky province is most abundant in

  14. Karen Hesse: From Grade School Writer to Newbery Medalist.

    ERIC Educational Resources Information Center

    Brodie, Carolyn S.

    2001-01-01

    Discusses author Karen Hesse's books for children and young adults; suggests ideas for related activities that include appropriate Web sites; and presents an annotated bibliography for books for young readers, books for older readers, audio, video, Web biographical information, print biographical information, and additional sources. (LRW)

  15. Flowage differentiation in an andesitic dyke of the Motru Dyke Swarm (Southern Carpathians, Romania) inferred from AMS, CSD and geochemistry

    NASA Astrophysics Data System (ADS)

    Nkono, Collin; Féménias, Olivier; Diot, Hervé; Berza, Tudor; Demaiffe, Daniel

    2006-06-01

    Two dykes of different thickness (5.5 m for TJ31 and 23 m for TJ34) from the late Pan-African calc-alkaline Motru Dyke Swarm (S. Carpathians, Romania) have been studied by electron microprobe (mineral chemistry), crystal size distribution (CSD), anisotropy of magnetic susceptibility (AMS) and whole-rock geochemistry. All the physical and chemical variations observed across the dyke's width point to concordant results and show that the variations of both modal abundance and size of the amphibole and biotite microphenocrysts inside the dykes (deduced from the classical CSD measurements) are the result of a mechanical segregation of suspended crystals during magmatic transport. Despite a pene-contemporaneous regional tectonic, the flow-induced differentiation in the thicker dyke is characterized by the concentration of pre-existing Ti-rich pargasite-tschermakite, clinopyroxene and plagioclase crystals in the core of the dyke and of the extracted differentiated liquid near the walls. This mechanical differentiation induces a chemical differentiation with a basaltic andesite composition for the core of the dyke whereas the margins are andesitic. Thus the chilled margins appear as a slightly more evolved liquid with a Newtonian behaviour when compared to the average composition of the dyke. The localization of the liquid on both sides of the dyke has certainly facilitated the ascent of the central part of the dyke that behaved as a Binghamian mush.

  16. The body in adolescent diaries. The case of Karen Horney.

    PubMed

    Seiffge-Krenke, Inge; Kirsch, Hiltrud Susanna

    2002-01-01

    The role of the body and its functions in the psychic life of the individual has occupied a central place in psychoanalytic thinking and writing. Developmentally, the body and the ego as a psychic organization have an integral, mutual relationship which becomes particularly important during adolescence, when the body matures physically while at the same time cognition, self-reflection, and social relations develop. This contribution presents results of the content analyses, focusing on the body, of 40 diaries written by twenty women during their adolescent years, compared with Karen Horney's adolescent diaries. In contrary to these diaries of the other young women, Karen Horney's adolescent diaries lack a focus on the body. Instead, idealized relationships with teachers are frequently mentioned. Only in the last diary, written at the transition to young adulthood, is the body, with a focus on sexual relations, more prominent. This discrepancy between Horney and female age-mates in normative samples is noteworthy. It is discussed here with emphasis on theoretical approaches about the body in adolescence in psychoanalysis, the importance of body and sexuality in Karen Horney's later life, Horney's contributions to female psychoanalysis, and her relationship with her father.

  17. Curved dyke trajectories beneath a mature volcanic edifice

    NASA Astrophysics Data System (ADS)

    Roman, A. M.; Jaupart, C. P.

    2013-12-01

    Curved dyke trajectories, prominently displayed at Spanish Peaks, Colorado, and observed in many different volcanic areas on Earth as well as on Venus, have been attributed to horizontal dyke propagation in a stress field that involves two different components: one due to magmatic overpressure in an central reservoir and another due to the regional tectonics. This model is not consistent with petrological and chronological constraints at Spanish Peaks: the dykes are filled with more evolved magmas than those of the central stock and are unambiguously younger than the stock (by about 1 My). These dykes are nowhere in contact with the stock and only appear at significant distances from it. For consistency with the observed trajectories, quantitative models of dyke propagation lead to very small values of the far-field tectonic stress that indicate very shallow levels of emplacement (≈1-2 km at most). At such small depths, the mechanics of deformation do not allow the growth of sizeable magmatic reservoirs. We propose instead that curved dyke trajectories are due to the combined effects of loading by a volcanic edifice in the axial zone and tectonic stresses in the far-field. We calculate principal stress trajectories and show that they exhibit the desired features. These trajectories are radially oriented beneath the edifice and bend away with increasing distance to align themselves with the tectonic stress. This model requires edifices with radii in the 5-15 km range and heights in the 1-3 km range, which are typical of mature stratovolcanoes worldwide. At Spanish Peaks, this model implies that the magmatic plumbing system that fed volcanic and intrusive activity developed in a manner consistent with the mechanics of dyke propagation beneath an edifice. Loading by a mature edifice generated a compressive stress field that prevented eruption in the central area. Dyke growth in the vertical direction was hampered beneath the highest part of the edifice and could

  18. Failure mechanisms during melt injection along dykes in Iceland

    NASA Astrophysics Data System (ADS)

    White, Robert S.; Agustsdottir, Thorbjorg; Greenfield, Tim; Green, Robert; Brandsdottir, Bryndis; Woods, Jennifer; Pugh, David

    2015-04-01

    We show moment tensor solutions from seismicity produced during two extremely well monitored dyke injections in the mid-crust of Iceland. They demonstrate failure by double couple mechanisms with little or no volumetric component. The inferred failure planes are consistently orientated parallel to the dyke, from which we infer that the seismicity is produced primarily by breaking chilled magma emplaced during an earlier injection episode. The first dyke injection was at Upptyppingar in 2007 in the Northern Rift Zone of Iceland. Melt was injected in the mid-crust from 17.5 to 13.5 km depth over a 9 month period before freezing in situ. The dyke was inclined with a dip of approximately 50 degrees. The second dyke was injected sub-horizontally from Bárðarbunga at a depth of about 7 km over a two week period in late August 2014 until it erupted 45 km away in Holuhraun. The Holuhraun eruption precisely reoccupied old craters from a late eighteenth century (c. 1797) eruption. The petrology of the eighteenth century basalts suggests that the melt also came from Bárðarbunga. It is likely therefore that the 2014 dyke closely followed the earlier eighteenth century dyke path. Both dyke injections were monitored by a dense seismic network of broad-band three-component seismic stations deployed and operated from 2006 to the present by the University of Cambridge in collaboration with the Institute of Earth Sciences, University of Iceland. These enable well constrained hypocentral locations and moment tensor solutions to be made. At its present peak the network consists of over 75 broadband seismometers. Fifteen additional seismometers were deployed in the days immediately following the onset of the dyke injection, including four seismometers on the Vatnajökull ice cap beneath which the dyke propagated and the remainder on Holuhraun surrounding the eventual eruption site: indeed two of the seismometers had to be rescued shortly before they were encroached by the advancing

  19. 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,…

  20. 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…

  1. Honoring the Complexities of Our Lives: An Interview with Karen Hesse.

    ERIC Educational Resources Information Center

    Bryant, Ellen Huntington

    1997-01-01

    Presents an interview with award-winning author Karen Hesse, discussing her writing for children and young adults. Discusses how ideas for particular books arose, as well as the research and writing processes that went into them. Appends reviews of nine books by Karen Hesse. (SR)

  2. 10. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

    10. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 NORTHWEST CORNER OF 'GREAT ROOM' - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

  3. 4. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

    4. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 SOUTHWEST CORNER - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

  4. 7. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

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

  5. 3. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

    3. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 SOUTHEAST CORNER - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

  6. 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

  7. 2. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

    2. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 SOUTH AND WEST ELEVATIONS - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

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

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

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

  9. 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

  10. 9. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

    9. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 INTERIOR WITH CLOSED FIREPLACE - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

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

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

    5. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer October 1959 MOULDING AND DENTIL COURSE ON SOUTH ELEVATION - White Meadow Farm, State Roads 290 & 262 (moved to Lewes, DE), Cool Spring, Sussex County, DE

  12. 1. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer ...

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

    1. Historic American Buildings Survey Cortlandt Van Dyke Hubbard, Photographer June 1960 EXTERIOR OF THE SOUTH AND EAST ELEVATIONS - The Judges Law Office, 100 West Market Street, Georgetown, Sussex County, DE

  13. Parasitic infections among Karen in Kanchanaburi Province, western Thailand.

    PubMed

    Nithikathkul, Choosak; Changsap, Bangon; Wannapinyosheep, Supaporn; Arnat, Naiyana; Kongkham, Somprathana; Benchawattananon, Rachadaporn; Leemingsawat, Somjai

    2003-01-01

    The purpose of this study was to determine the rate of intestinal parasitic and malarial infections during a period of low infection among the residents of remote Karen villages in Thailand. Fifty-five males and 64 females, aged 6 months to 70 years, were examined for malaria by thick blood smears using the Giemsa staining technique. Of the 119 subjects, 4 (3.36%) showed positive for malaria with vivax gametocytes. Results suggested that mass screening was not an effective way for diagnosing malaria. Stool samples were examined under a light microscope. The overall intestinal parasitic infection rates were 38.24% in 34 males, and 36.11% in 36 females. These were hookworm (17.14%), Ascaris lumbricoides (7.14%), Trichuris trichiura (1.43%), Strongyloides stercoralis (7.14%), Taenia spp (1.43%), Entamoeba histolytica (1.43%), Entamaeba coli (10.00%) and Giatdia lamblia (1.43%). The highest (55.55%) and lowest (16.66%) rates of infection were observed in age groups 0-5 and over 45, years respectively. In addition, A. lumbricoides and T. trichiura were found more frequently in children, while hookworms was found similarly in every age group. Results showed that the Karen living along the western border of Thailand possessed high rates of intestinal parasitic infections. Strict monitoring and control programs for these parasites should be implemented.

  14. "Can I Ask That?": Perspectives on Perinatal Care After Resettlement Among Karen Refugee Women, Medical Providers, and Community-Based Doulas.

    PubMed

    LaMancuso, Kate; Goldman, Roberta E; Nothnagle, Melissa

    2016-04-01

    This study characterized the perspectives of Karen refugee women in Buffalo, NY, their medical providers, and Karen interpreters/doulas on perinatal care for Karen women in resettlement. In-depth qualitative interviews with Karen women (14), Karen doulas/interpreters and key informants (8), and medical providers (6) were informed by the social contextual model and focused on women's questions about and opinions of perinatal care in Buffalo and on providers' experiences caring for Karen patients. Karen women expressed gratitude for and understanding of perinatal care in Buffalo, and providers described Karen patients as agreeable but shy. Karen doulas offered an alternative view that exposed women's many questions and concerns, and described how doula training empowered them as patients' advocates. Low self-efficacy, trauma histories, and cultural expectations may contribute to Karen women's seeming agreeability. Doulas/interpreters possess insider knowledge of women's concerns and facilitate communication between patients and the care team.

  15. A Miocene basanite peperitic dyke at Stanley, northwestern Tasmania, Australia

    NASA Astrophysics Data System (ADS)

    Goto, Yoshihiko; McPhie, Jocelyn

    1996-11-01

    A Miocene basanite dyke at Stanley, northwestern Tasmania, Australia, displays well preserved peperite texture. The dyke is 2 m wide and has intruded basaltic breccia ("host sediment"). One contact of the dyke is fluidally shaped, and amoeboid apophyses 10-25 cm long extend into the host sediment, whereas the other contact is characterized by blocky peperite texture comprising tabular to wedge-shaped clasts up to 30 cm across separated by host sediment. The clasts have internal spherical fractures and some show splinter texture. Vesicles are common in the clasts, and those intersected by clast margins have been filled with sediment. The interior of the dyke comprises close-packed blocky peperite consisting of tabular, wedge-shaped and polyhedral clasts tens of centimetres across separated by host sediment. These clasts show well developed jigsaw-fit texture. The textures and structures in the basanite dyke are inferred to have formed in two stages: an earlier, hotter, apophysis-forming stage and a later, cooler, angular clast-forming stage, both of which occurred during the intrusion of magma into wet, poorly consolidated sediment in a shallow marine environment. During the apophysis-forming stage, the magma had relatively low viscosity and progressively displaced wet sediment. The wet sediment around the dyke was partly fluidized by vaporization of pore water. The angular clast-forming stage reflects a change in the rheological behaviour of the magma from ductile to brittle, most likely in response to decreasing temperature. The chilled parts of the dyke were subject to stress arising from cooling contraction and also from continued, pulsatory movement of hotter, still ductile magma in the interior of the dyke, resulting in brittle fragmentation. Brittle fragmentation was accompanied by movement of host sediment into the newly created open spaces, forming blocky peperite. Spherical fractures, splinter texture and sediment-filled vesicles formed during the angular

  16. Weibull-distributed dyke thickness reflects probabilistic character of host-rock strength

    PubMed Central

    Krumbholz, Michael; Hieronymus, Christoph F.; Burchardt, Steffi; Troll, Valentin R.; Tanner, David C.; Friese, Nadine

    2014-01-01

    Magmatic sheet intrusions (dykes) constitute the main form of magma transport in the Earth’s crust. The size distribution of dykes is a crucial parameter that controls volcanic surface deformation and eruption rates and is required to realistically model volcano deformation for eruption forecasting. Here we present statistical analyses of 3,676 dyke thickness measurements from different tectonic settings and show that dyke thickness consistently follows the Weibull distribution. Known from materials science, power law-distributed flaws in brittle materials lead to Weibull-distributed failure stress. We therefore propose a dynamic model in which dyke thickness is determined by variable magma pressure that exploits differently sized host-rock weaknesses. The observed dyke thickness distributions are thus site-specific because rock strength, rather than magma viscosity and composition, exerts the dominant control on dyke emplacement. Fundamentally, the strength of geomaterials is scale-dependent and should be approximated by a probability distribution. PMID:24513695

  17. Weibull-distributed dyke thickness reflects probabilistic character of host-rock strength.

    PubMed

    Krumbholz, Michael; Hieronymus, Christoph F; Burchardt, Steffi; Troll, Valentin R; Tanner, David C; Friese, Nadine

    2014-01-01

    Magmatic sheet intrusions (dykes) constitute the main form of magma transport in the Earth's crust. The size distribution of dykes is a crucial parameter that controls volcanic surface deformation and eruption rates and is required to realistically model volcano deformation for eruption forecasting. Here we present statistical analyses of 3,676 dyke thickness measurements from different tectonic settings and show that dyke thickness consistently follows the Weibull distribution. Known from materials science, power law-distributed flaws in brittle materials lead to Weibull-distributed failure stress. We therefore propose a dynamic model in which dyke thickness is determined by variable magma pressure that exploits differently sized host-rock weaknesses. The observed dyke thickness distributions are thus site-specific because rock strength, rather than magma viscosity and composition, exerts the dominant control on dyke emplacement. Fundamentally, the strength of geomaterials is scale-dependent and should be approximated by a probability distribution.

  18. Geochemistry of eastern North American CAMP diabase dykes

    NASA Astrophysics Data System (ADS)

    Callegaro, S.; Marzoli, A.; Bertrand, H.; Reisberg, L. C.; Chiaradia, M.; Bellieni, G.

    2011-12-01

    The Piedmont area of the Appalachians and the coastal plains of eastern North America (ENA) were intruded between 202 and 195 Ma[1,2] by swarms of diabase (dolerite) dykes and a few sills of the Central Atlantic magmatic province (CAMP). Different trends are observed for the dykes, from NW (more frequent in the South), to N-S and NE, thus a radial pattern and a coeval emplacement driven by the bulging effect of a mantle plume were initially inferred[3]. Conversely, based on field data, an age progression can be defined from NW- to N- and NE-oriented dykes, supporting a diachronous northward rift-to-drift transition during Pangaea break-up. New geochemical data on 74 ENA dykes suggest a dominant lithospheric mantle source for these magmatic suite. A deep enriched mantle source is further discarded by the crystallization temperatures (ca.1350°C) calculated[4] for high-Fo (up to Fo89) olivines, which do not reflect very hot (i.e. mantle-plume) potential mantle temperatures. Incompatible trace element contents are fairly homogeneous and generally low, e.g. (La/Yb)Ch (0.54-2.39), typical of melts derived from a quite depleted shallow (spinel) mantle-source. However, isotopic compositions of ENA dykes display a considerable spread in initial isotopic signatures, do not show correlation with incompatible trace elements, and are independent of the orientation and age of the dykes, i.e. 87Sr/86Sr200Ma (0.7043-0.7088), ɛNd200Ma (-6.67-+2.42) and 206Pb/204Pb200Ma (17.46-18.61). Pb isotopic compositions plot above the NHRL, at positive Δ7/4 (10-17) and Δ8/4 (19-73), calling for an enriched ancient component in the mantle source. Unradiogenic 187Os/188Os200Ma ratios (0.127-0.144) argue for negligible amounts of crustal contamination and, coupled with the large range of Sr-Nd-Pb isotopic compositions, suggest generation from a strongly heterogeneous mantle source, probably metasomatized lithosphere. Lithospheric mantle underlying the Appalachian orogen may have undergone

  19. 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.

  20. 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…

  1. Permanent groundwater storage in basaltic dyke fractures and termite mound viability

    NASA Astrophysics Data System (ADS)

    Mège, Daniel; Rango, Tewodros

    2010-04-01

    Many basaltic dykes of the Ethiopian flood basalt province are observed in the northwestern Ethiopian lowlands. In this area, the termites preferentially build their epigeous mounds on the top of dolerite dykes. The relationship between termite mounds and dykes is investigated from the analysis of their distribution along one of these dykes, of thickness 2-5 m, that we could follow over 2000 m. Termite mounds are periodically spaced (mean distance 63 m, R2 = 0.995), and located exclusively where the topographic relief of the dyke is not more than 2 m above the surrounding area. From these observations and from the geological context, a hydrological circuit model is proposed in which (1) dykes are preferential conduits for groundwater drainage during the rainy season due to pervasive jointing, (2) during the dry season, the portion of the dyke forming a local topographic relief area dries up more quickly than the surroundings, the elevation difference between the dyke summit and the surroundings being a factor restricting termite mound development. For dyke topographic relief >2 m, drying is an obstacle for maintaining the appropriate humidity for the termite colony life. Periodic termite mound spacing is unlikely to be related to dyke or other geological properties. It is more likely related to termite population behaviour, perhaps to clay shortage, which restricts termite population growth by limiting the quantity of building material available for mound extension, and triggers exploration for a new colonization site that will be located along the dyke at a distance from the former colony that may be controlled by the extent of the zone covered by its trail pheromones. This work brings out the importance of dykes in channelling and storing groundwater in semiarid regions, and shows that dykes can store groundwater permanently in such settings even though the dry season is half the year long. It contributes also to shedding light on water supply conditions

  2. 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

  3. 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).

  4. 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.

  5. Effect of host-rock rheology on dyke shape, thickness, and magma overpressure.

    NASA Astrophysics Data System (ADS)

    Vachon, Rémi; Hieronymus, Christoph F.

    2016-12-01

    The size and thickness of dykes is of fundamental importance for volcano dynamics because dykes are the primary path for magma transport, and because large numbers of dykes often comprise a major proportion of the volcanic edifice and of the underlying crust. Standard elastic models predict dyke geometry to be elliptic in cross-section for constant overpressure and uniform host-rock properties, whereas observations show that dyke thickness is typically more nearly constant with a sharp taper at the ends. Moreover, the predicted overpressures required to inflate dykes in a purely elastic medium are often significantly higher (>150 MPa and up to 2 GPa) than those estimated by other means (about 1-50 MPa). In this study, we use two-dimensional finite element models to test whether other host-rock rheologies lead to more realistic dyke shapes and overpressures. We examine 3 different rheologies, each of which is affected by the presence of the dyke itself: (1) elasticity with reduced moduli in regions of low pressure or tension; (2) elasto-plasticity with plastic failure in the high-stress regions surrounding the dyke tips; (3) visco-elasticity with a viscosity decrease due to heating by the dyke. We use rheological parameters obtained from laboratory experiments whenever possible, and assume static conditions for the final dyke shape. We find that all 3 rheologies tend to make the dyke more rectangular relative to the elliptical dykes of the linearly elastic models. The change in shape is due to enhanced deformation in the high-stress zone surrounding the dyke tip. We also find that the overpressure required to inflate an initially thin dyke to a given thickness is reduced for all 3 rheologies. The greatest decrease in overpressure by a factor of about 0.1 is observed for the elasto-plastic model, and for the visco-elastic model if the dyke intrudes into moderately pre-heated host-rock. We discuss our results with respect to dyke observations from Rum Island (Scotland

  6. Effect of host-rock rheology on dyke shape, thickness and magma overpressure

    NASA Astrophysics Data System (ADS)

    Vachon, Rémi; Hieronymus, Christoph F.

    2017-03-01

    The size and thickness of dykes is of fundamental importance for volcano dynamics because dykes are the primary path for magma transport, and because large numbers of dykes often comprise a major proportion of the volcanic edifice and of the underlying crust. Standard elastic models predict dyke geometry to be elliptic in cross-section for constant overpressure and uniform host-rock properties, whereas observations show that dyke thickness is typically more nearly constant with a sharp taper at the ends. Moreover, the predicted overpressures required to inflate dykes in a purely elastic medium are often significantly higher (>150 MPa and up to 2 GPa) than those estimated by other means (about 1-50 MPa). In this study, we use 2-D finite element models to test whether other host-rock rheologies lead to more realistic dyke shapes and overpressures. We examine three different rheologies, each of which is affected by the presence of the dyke itself: (1) elasticity with reduced moduli in regions of low pressure or tension; (2) elastoplasticity with plastic failure in the high-stress regions surrounding the dyke tips; (3) viscoelasticity with a viscosity decrease due to heating by the dyke. We use rheological parameters obtained from laboratory experiments whenever possible, and assume static conditions for the final dyke shape. We find that all three rheologies tend to make the dyke more rectangular relative to the elliptical dykes of the linearly elastic models. The change in shape is due to enhanced deformation in the high-stress zone surrounding the dyke tip. We also find that the overpressure required to inflate an initially thin dyke to a given thickness is reduced for all three rheologies. The greatest decrease in overpressure by a factor of about 0.1 is observed for the elastoplastic model, and for the viscoelastic model if the dyke intrudes into moderately pre-heated host-rock. We discuss our results with respect to dyke observations from Rum Island (Scotland

  7. Geological consequences of the Saemangeum Dyke, mid-west coast of korea: A review

    NASA Astrophysics Data System (ADS)

    Lee, Hee Jun; Lee, Soo Hwan

    2012-12-01

    The Saemangeum Dyke is located in an estuarine setting, regulated in a complicated manner by a macrotidal regime, rivers, and winter monsoon. Accordingly, the constructed dyke resulted in a variety of artificial changes in geological characteristics in the estuary and its vicinity. To investigate those dyke-induced changes, the KORDI (Korea Ocean Research and Development Institute) performed sedimentological and sediment-dynamical observations from 2002 to 2010. On the basis of the KORDI results, the major geological changes and associated dynamical processes are reviewed. Five phenomena, among others, are focused on: depositional-channel creation; gap-related erosion; forced movements of surface sands; tidal-flat growth inside the dyke; and blanketing of mud over the sandy seafloor. These phenomena were unforeseen before the dyke construction, and reflect that the dyke could cause both erosion and deposition on an estuarine scale. The investigations conclude that the sediments in the dyke-influenced region were derived from the two rivers, Mangyeong and Dongjin, of the estuary. This is completely contrary to the offshore origin proposed before the dyke construction. As a result, the review supports the proposal that a thorough geological investigation and rational forecast is necessary prior to dyke construction to avoid economic loss and a fractious environmental debate.

  8. 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…

  9. 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'…

  10. The influence of administrative leadership: an interview with Dr Karen S. Hill.

    PubMed

    Hill, Karen S; Adams, Jeffrey M

    2015-01-01

    This department highlights nursing leaders who have demonstrated a commitment to patient care leadership and innovation in practice, policy, research, education, and theory. This interview profiles Karen Hill, DNP, RN, NEA-BC, FACHE, FAAN, chief operating officer and chief nursing officer of Baptist Health in Lexington, Kentucky, and editor-in-chief of the Journal of Nursing Administration.

  11. 77 FR 68149 - Karen Paul Holley, M.D.; Decision and Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-15

    ... Certificate of Registration be revoked and that any pending application to renew or modify her registration be....100(b), I order that DEA Certificate of Registration Number BH8988339, issued to Karen P. Holley, M.D...., to renew or modify her registration, be, and it hereby is, denied. This Order is effective...

  12. 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…

  13. Newbery Medal Winner Karen Hesse Brings Billie Jo's Voice "Out of the Dust."

    ERIC Educational Resources Information Center

    Hendershot, Judy; Peck, Jackie

    1999-01-01

    Describes an interview with children's author Karen Hesse, discussing such things as how she chose writing as a career, her use of figurative language and her skillful crafting of dialog, where her book ideas come from, and her latest projects. (SR)

  14. Consider the Source: Feminism and Point of View in Karen Hesse's "Stowaway" and "Witness."

    ERIC Educational Resources Information Center

    Glenn, Wendy J.

    2003-01-01

    Notes how Karen Hesse strays from her typical pattern of exploring gender issues to provide a look at patriarchal culture from within, in one case, and from multiple points of view in the other, ultimately strengthening the feminist pulse that beats within her earlier works. Concludes that in "Stowaway" and "Witness," the voice of a boy and the…

  15. Dyke Monitorin by the Means of Persistent Scattering Interferometry at the Coast of Northern Germany

    NASA Astrophysics Data System (ADS)

    Seidel, M.; Marzahn, P.; Ludwig, R.

    2016-06-01

    40 percent of the world's population are presently living in coastal areas or along the main rivers. Taking into account that the vulnerability of these areas is increasing due to sea-level rise and coastal hazards such as storm surges or extreme rainfall events accompanied with floods, the importance of safety structures such as dykes is increasing as well. Hence, a spatial distributed dyke monitoring should be part of a sustainable adaptation strategy. Due to increasing amount of SAR-data from various satellites with high spatial and temporal coverage, the means of SAR-interferometry could be an essential tool to ensure this kind of required monitoring. Given this prospect, Persistent Scattering Interferometry (PSI) will be a very suitable monitoring technique for dyke structures to identify dyke movement with the accuracy of few millimetres. This procedure focuses on pixels that show a stable scattering behaviour in a sequence of multiple SAR-scenes. In opposition to ground-measurements, the spatial coverage of this technique provides comparable results for different parts of the dyke; furthermore weak segments with particular high movements could be identified in advance. This could prevent future dyke crevasses and help to reduce risks in high-populated areas. This paper attempts to describe the potential of the PSI technique for a spatial distributed dyke monitoring at the coast in northern Germany. 21 ERS-2 scenes and 16 Envisat ASAR scenes were analysed. Those Scenes cover an area of a sea shore dyke including a flood regulation barrage and results point out the potential for this technique to monitor dyke structures. Even though the observed dyke doesn't show any significant deformation rates, the two datasets show the same signal for the whole dyke.

  16. Fault-related carbonate breccia dykes in the La Chilca area, Eastern Precordillera, San Juan, Argentina

    NASA Astrophysics Data System (ADS)

    Castro de Machuca, Brígida; Perucca, Laura P.

    2015-03-01

    Carbonate fault breccia dykes in the Cerro La Chilca area, Eastern Precordillera, west-central Argentina, provide clues on the probable mechanism of both fault movement and dyke injection. Breccia dykes intrude Upper Carboniferous sedimentary rocks and Triassic La Flecha Trachyte Formation. The timing of breccia dyke emplacement is constrained by cross cutting relationships with the uppermost Triassic unit and conformable contacts with the Early Miocene sedimentary rocks. This study supports a tectonic-hydrothermal origin for these breccia dykes; fragmentation and subsequent hydraulic injection of fluidized breccia are the more important processes in the breccia dyke development. Brecciation can be triggered by seismic activity which acts as a catalyst. The escape of fluidized material can be attributed to hydrostatic pressure and the direction of movement of the material establishes the direction of least pressure. Previous studies have shown that cross-strike structures have had an important role in the evolution of this Andean segment since at least Triassic times. These structures represent pre-existing crustal fabrics that could have controlled the emplacement of the dykes. The dykes, which are composed mostly of carbonate fault breccia, were injected upward along WNW fractures.

  17. Paleomagnetism of the 1210 Ma Gnowangerup-Fraser dyke swarm, Western Australia

    NASA Astrophysics Data System (ADS)

    Pisarevsky, S. A.; Li, Z. X.; Wingate, M. T. D.; Tohver, E.

    2012-04-01

    The Gnowangerup-Fraser mafic dyke swarm is part of the Marnda Moorn LIP and subparallel to the southern and southeastern margins of the Yilgarn Craton. Some dykes become progressively recrystallized towards the craton margin and others are strongly deformed within the orogen, implying that at least some dykes were emplaced prior to the youngest deformation in the Albany-Fraser Orogen. Five dykes have previously yielded U-Pb ages between 1203 and 1218 Ma, and the primary nature of the magnetic directions in a 1212 Ma Fraser dyke is supported by a positive baked-contact test. We collected paleomagnetism samples from 19 dykes, along the Phillips and Fitzgerald Rivers, and near Ravensthorpe. AF demagnetisation revealed a stable bipolar remanence in 13 dykes. The mean paleomagnetic pole is almost identical to the VGP of the 1212 Ma Fraser dyke. The combined robust paleopole places the West Australian Craton in a near-polar position at 1210 Ma. Comparison with coeval Laurentian paleopoles indicates that Laurentia and Australia were widely separated at that time.

  18. 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…

  19. 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.

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

    NASA Astrophysics Data System (ADS)

    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.

    2015-01-01

    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.

  1. Segmented lateral dyke growth in a 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; Ágústsdóttir, Thorbjörg; Björnsson, Helgi; Bean, Christopher J.

    2015-04-01

    Crust at many divergent plate boundaries forms primarily by the injection of vertical sheet-like dykes, some tens of km long. Previous models of rifting events indicate either a 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. We show how a recent segmented 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 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 a magma source deflation and slow collapse at the Bárðarbunga caldera, accompanied by a series of M>5 earthquakes. The 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.

  2. Refractory Seizure in Childhood: Dyke-Davidoff-Masson Syndrome Revisited

    PubMed Central

    Dutta, Abhijit; Bose, Sagar; Sen, Kaushik; Pandit, Narayan; Sharma, Samarth

    2016-01-01

    Dyke-Davidoff-Masson syndrome (DDMS) is a rare disorder characterized by recurrent seizures, facial asymmetry, contralateral hemiplegia, radiologic features of cerebral hemiatrophy, and ipsilateral compensatory hypertrophy of the skull bone and sinuses. We describe three cases of children with DDMS, who initially presented with refractory seizure to the pediatric department of North Bengal Medical College and Hospital, India. In each case, the clinical features noted along with computed tomography or magnetic resonance imaging helped confirm the diagnosis of DDMS. DDMS should be considered as a differential diagnosis of refractory seizures in children. We seek to emphasize the importance of thorough clinical and neuroimaging workup of seizure disorder in children for the proper management of the condition. PMID:27403244

  3. Dyke Propagation Through a Partially Submerged Volcanic Edifice

    NASA Astrophysics Data System (ADS)

    Tait, S.; Taisne, B.; Limare, A.; Manga, M.; Pasquet, E.

    2014-12-01

    We have studied using analogue experiments the ascent of magma through a volcanic edifice. The edifice is simulated using a cone of gelatine and the magma is an aqueous solution. The latter is injected at the base of the cone and propagates through the edifice in hydraulic fractures that represent dykes. The buoyancy of the magma with respect to the edifice is varied by adjusting salt concentration in the aqueous solution and/or sugar concentration in the gelatine. The system is axisymmetric. After the gelatin is released from its mold, it is partially submerged in a layer of water that represents the surrounding ocean. Because the gelatin is denser than water, its weight generates an axisymmetric stress field in the edifice whose amplitude depends, for a given edifice density, on the depth of the water which represents ''sea-level''. We derive the geometry and amplitude of this stress field by using birefringence in the gelatin that results from its photoelasticity. We document the geometry of the dykes as they propagate and the elevation of eruptive fissures on the edifice as a function of the dimensionless parameters governing the system. Positive buoyancy of the magma tends to favour summit eruptions and increasing weight of the edifice (lower sea-level with respect to edifice height) tends to favour flank eruptions. We compare the experimental results with a dataset from Piton de la Fournaise, Reunion Island and draw some general conclusions about expected changes in eruptive behaviour as a volcanic island grows to greater and greater altitude above sea-level.

  4. Paleomagnetism of the ~1.1 Ga Baraga-Marquette dykes (Michigan, USA)

    NASA Astrophysics Data System (ADS)

    Piispa, E. J.; Foucher, M. S.; Chmielewski, J. A.; Smirnov, A. V.; Pesonen, L. J.

    2014-12-01

    We present new detailed paleomagnetic and rock magnetic results from ~50 dykes exposed in the Baraga-Marquette (BM) area of the Upper Peninsula of Michigan (USA). The dyke intrusion was associated with the development of the ~1.1 Ga North American Mid-Continent Rift (MCR) system. Most rocks representing the early stage of MCR are characterized by steep reversed directions of the characteristic remanent magnetization (ChRM), whereas the rocks from the main stage of MCR generally yield shallower normal polarity ChRM directions. Rock magnetic experiments show that the principal magnetic carrier in the BM dykes is single-domain to pseudosingle-domain magnetite or low-Ti titanomagnetite with minor occurrences of hematite, maghemite, or pyrrhotite in some dykes. The majority of BM dykes yielded steep reversed-polarity directions of ChRM indicating that they belong to the early stage of MCR development. The corresponding paleomagnetic pole plots close to the apex of the so called "Logan Loop", a segment of the Apparent Polar Wander Path (APWP) for the North American continent for ~1000-1200 Ma. Several BM dykes yielded steep normal-polarity ChRM directions, significantly different from the direction exhibited by the normally magnetized MCR sequences. This may indicate that these dykes are older than the reversed polarity dykes. In addition, a single mafic dyke from the Baraga basin with a recently published U/Pb age of 1120±4 Ma resulted in a shallow normal ChRM direction. The implications of our new paleomagnetic results for the North American APWP and the evolution of MCR will be discussed.

  5. Thermal perturbation, mineral assemblages, and rheology variations induced by dyke emplacement in the crust

    NASA Astrophysics Data System (ADS)

    Lavecchia, Alessio; Clark, Stuart R.; Beekman, Fred; Cloetingh, Sierd A. P. L.; Burov, Evgueni

    2016-05-01

    We constructed a thermomechanical model to examine the changes in rheology caused by the periodic intrusion of basaltic dykes in a two-layered continental crust. Dyke intrusion can locally change the mineralogical composition of the crust in space and time as a result of temperature-induced metamorphism. In our models we paid particular attention to determine how different mineral assemblages and reaction kinetics during metamorphism impact on the thermomechanical behavior of the crust, in terms of differential stress values. We investigated several lithologies characteristic for intracontinental crust: (1) a quartz-feldspathic crust (QF), (2) a crust with a mineralogical assemblage resembling the average chemical composition occurring in literature (CC), and (3) a micaschist crust (MS). Our model shows that temperature profiles are weakly influenced by metamorphism, with negligible variations in the T-t paths. The results indicate that intrusion-induced changes in the crustal rheology are strongly dependent on mineralogical assemblage variation. The strength of a dyke aureole in the upper crust increases during dyke emplacement, which may cause migration of later dykes and influence the dyke spacing. In contrast, in the lower crust the strength of a dyke aureole decreases during dyke emplacement. Fast kinetics results in a ductile lower crust in proximity of the dykes, whereas slower kinetics leads to the formation of partial melts and subsequent switch from ductile to brittle behavior. Lithology exerts a dominant role on the quantity of melt produced, with higher volume percentages occurring in the MS case study. Produced melts may migrate and support acidic volcanic activity.

  6. Ultradepleted adcumulates from a late-stage mafic dyke of the Bayantsagaan layered intrusion, Mongolia

    NASA Astrophysics Data System (ADS)

    Chistyakova, Sofya; Latypov, Rais

    2013-04-01

    It is commonly expected that late-stage dykes in mafic layered intrusions must be strongly enriched in all incompatible components that are concentrated in the evolved residual melt. Our recent study of one late-stage dyke from the Bayantsagaan layered intrusion (Mongolia) has revealed, however, that this is not always the case. This 11 cm thick dyke is composed of quite fresh, fully crystalline troctolite with no signs of chilling against host leucotroctolite. Texturally, both dyke and leucotroctolite are composed of medium-grained plagioclase-olivine-magnetite cumulate. The dyke is, however, finer-grained and more adcumulate than leucotroctolite as evident from a much less amount of intercumulus material mainly represented by interstitial amphibole (5 vol.% versus 10 vol.%). The dyke shows three distinctive geochemical features. Firstly, it is compositionally more evolved than leucotroctolite as indicated by notably lower real and normative An-content of plagioclase, whole-rock Mg-number and Cr and higher whole-rock TiO2. Secondly, despite of being more evolved, the dyke is notably depleted in all incompatible components (e.g. K2O, Y, REE). Their concentrations in the dyke are several times lower than in host leucotroctolite (e.g. 0.015 ppm versus 0.112 ppm for Dy). Thirdly, the dyke reveals internal reverse zonation with an inward increase in compatible MgO, TiO2 and normative An-content and a decrease in all incompatible components (e.g. REE). Such a distribution of incompatible components is indicative of an inward decrease in the amount of trapped melt, in other words, the dyke becomes inwards progressively more adcumulate. In layered intrusions, adcumulates are commonly attributed to the almost complete removal of interstitial liquid enriched in incompatible elements from cumulate pile by some primary cumulus (e.g. in situ growth) or post-cumulus processes (e.g. compaction, compositional convection, thermal migration). These processes are, however, not

  7. Looking for Asian butch-dykes: exploring filmic representations of East Asian butch-dykes in Donna Lee's Enter the Mullet.

    PubMed

    Lin, Hui-Ling

    2009-01-01

    Asian butch-dykes have been overlooked in analyses of Chinese cinema, studies that often concentrate on "feminized" transgender roles. This article examines cinematic representations of Asian butch-dykes through film analysis of Enter the Mullet (2004), a five-minute short, and in-depth interviews with the filmmaker, Donna Lee, a Chinese-Canadian in Vancouver. Lee's film is inspired by Enter the Dragon (1973), starring Bruce Lee, the most recognized icon of Asian masculinity. Combining with the mullet hairstyle, which is often associated with White working-class, the filmmaker introduces viewers to the hybrid masculinity of Asian butch-dykes. The article argues that Asian female masculinity can be a strategic means of destabilizing the hegemony of White-male-middle-class masculinity.

  8. Proterozoic Geomagnetic Field Geometry from Mafic Dyke Swarms

    NASA Astrophysics Data System (ADS)

    Panzik, J. E.; Evans, D. A.

    2012-12-01

    Pre-Mesozoic continental reconstructions and paleoclimatic inferences from paleomagnetism rely critically upon the assumption of a time-averaged geocentric axial dipole (GAD) magnetic field. We have been testing the GAD assumption empirically, by compiling paleomagnetic remanence directional variations among coeval volcanic rock suites distributed over large areas of the Earth's surface. We compute virtual geomagnetic poles (VGPs) from site-mean remanence data using either a pure GAD model, or alternative models with varying amounts of zonal quadrupole or octupole fields. Rastering through quadrupole vs. octupole space, we produce contour plots of precision/dispersion for the mean of VGPs in each computation. Using the 0-5 Ma volcanics global database as a test, our method shows results consistent with the compilations of Schneider & Kent (1990, Rev. Geophys. 28, 71-96) and McElhinny et al. (1996, JGR 101, 25007-25027), notably reproducing the reversal asymmetry in a significant (order 3%) quadrupolar contribution. Performing the same test on ancient mafic dyke swarms, the Karoo-Ferrar large igneous province (ca. 0.18 Ga) and the central Atlantic magmatic province (CAMP) (0.20 Ga) datasets are consistent with a range of models, including both GAD and independent estimates of non-GAD contributions derived from global tectonic reconstructions (Torsvik & Van der Voo, 2002, GJI 151, 771-794). The method is limited by paleolongitudinal restriction of ancient LIPs, for similarly restrictive sub-sampling of the 0-5 Ma volcanic data can generate results that differ dramatically from the global mean (e.g., the far-sided offset of VGPs relative to the spin axis). Analysis of pre-Pangean datasets is limited by the uncertainty of tectonic reconstructions, but within solely the intact North American (Laurentian) craton, the Franklin (ca. 0.72), Mackenzie (ca. 1.27) and Matachewan (2.45 Ga) dyke swarms are used as Pre-Mesozoic targets that have large areal coverage. None of the

  9. Groundmass crystallization in dacite dykes taken in Unzen Scientific Drilling Project (USDP-4)

    NASA Astrophysics Data System (ADS)

    Noguchi, Satoshi; Toramaru, Atsushi; Nakada, Setsuya

    2008-07-01

    Groundmass textural and compositional analyses of the drilled dacite dykes of the Unzen Scientific Drilling Project (USDP-4) identify the feeder dyke of the 1990-1995 eruption and elucidate the crystallization process of dykes at depth. In the drilling depth range of 1582-1996 m ("conduit zone"), four dacite dykes were recognized. The groundmasses of all but one of these dykes have textures ranging from cryptocrystalline to microcrystalline aggregate of crystals < 10 µm across forming an equigranular mosaic of plagioclase, alkali feldspar, quartz, and pyrite. The samples include a small number of coarser-grained plagioclase microlites (20 µm to 0.3 mm long). The compositions of groundmass consisting only of grains < 10 µm plotted at the lower pressure (< 50 MPa) ternary minimum in the Qz'-Ab'-Or' system suggests that the crystallization of plagioclase, alkali feldspar, and quartz took place nearly simultaneously. The compositions of coarser plagioclase microlites and groundmass, the plagioclase microlite textures, and the phenocryst assemblages show significant differences from historical lavas exposed in the summit area. This implies the possibility that most of the dacite dykes are not feeder dykes for the lavas at the summit and remained beneath the surface, perhaps because of high viscosity associated with high SiO 2. One sample C14-1-1 collected 1977 m, has a texture, composition, and phenocryst assemblage nearly identical to that of the dome lava of the 1990-1995 eruption, differing only in the presence of hydrothermal alternation. At this time we cannot definitely conclude that C14-1-1 was the feeder dyke for the 1990-1995 eruption until we can elucidate the time scale and the conditions governing hydrothermal alternation.

  10. 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.

  11. 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.

  12. Significance of ferrimagnetism in chromitites from the Great Dyke, Zimbabwe

    NASA Astrophysics Data System (ADS)

    Fernandes, T. R. C.

    1999-02-01

    Primary igneous Cr spinels from undisturbed parts of seam number 4 of the Great Dyke occur as pristine euhedral crystals and exhibit paramagnetism. Tectonic stress, which results in failure by brittle deformation and stress-induced migration of cations within the spinel lattice, affects the microstructure and magnetic properties of the spinels. Sheared samples are ferrimagnetic and exhibit a composite hysteresis loop with a ferrimagnetic and a paramagnetic component. The ratio of {Mrs}/{Ms} (0.65), Curie temperatures of 100-533°C and the low temperature susceptibility curve of the sheared chromitites are not readily interpreted in terms of the common magnetic minerals. Changes in inter-atomic distances and bond angles resulting from rearrangements of cations in the lattice, defects and oxidation of Fe 2+ to Fe 3+ allow enhanced exchange interactions with the oxygen atoms and give rise to the observed magnetic properties of the sheared samples. In combination with previous work, these observations indicate that magnetic susceptibility may be used as an indicator of ore quality both in the field and at the processing plant. Furthermore, the differences in the magnetic properties of the chromitites may be used for beneficiation of the ores and has potential for process control in a ferroalloy smelter.

  13. Radiological imaging findings of Dyke-Davidoff-Masson syndrome.

    PubMed

    Gökçe, Erkan; Beyhan, Murat; Sade, Recep

    2017-04-03

    Radiological findings of Dyke-Davidoff-Masson syndrome (DDMS) in patients with different etiologies are presented in our study. The study included 12 patients (seven females, five males) for whom radiological examinations were requested due to reasons such as epilepsy, mental retardation, and/or hemiplegia. CT was performed in 12, MRI in 6, MRA in 1, and DSA in 1 patient. Following imaging findings were evaluated: cerebral and cerebellar involvement (laterality, encephalomalacia), affected territories, ventricular enlargement, sulcal enlargement, calvarial thickening, and paranasal sinus enlargement hyperaeration. Age range of the patients was 5-62 (mean 34.1 ± 21.7). Left hemicrania was affected in eight patients, right hemicrania in four. Ipsilateral calvarial thickening and lateral ventricular dilatation were observed in all patients. 11 patients had ipsilateral frontal sinus hyperaeration, sulcal enlargement and encephalomalacia. Wallerian degeneration of the mesencephalon and middle fossa hypoplasia was seen in ten patients, mastoid hyperaeration, third ventricular enlargement and thalamic involvement in nine, and corpus callosum, basal ganglion injury, and sphenoid sinus hyperaeration in eight. MCA, ACA, and PCA territories were involved in six patients. Only MCA territory involvement was seen in four patients. Cerebellar atrophy was contralateral in two patients. Symmetric bilateral atrophy was observed in one patient. DDMS can be encountered with different radiological findings based on cerebral damage formation process and the extent of damage. Patients may have different levels of cerebral hemiatrophy, ipsilateral carvarial thickening, and lateral ventricular dilatation.

  14. 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.

  15. "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…

  16. High-resolution Seismic Reflection Imaging of Thin, Diamondiferous Kimberlite Dykes and Sills

    NASA Astrophysics Data System (ADS)

    Hammer, P. T.; Clowes, R. M.; Ramachandran, K.

    2003-12-01

    A unique seismic reflection experiment has successfully imaged a thin, diamondiferous kimberlite dyke intruded into granitic host rock. Although the typical dyke thickness is only 1-3 m, it is mapped from the near-surface to 1500 m depth. Such an application of seismic techniques to the diamond exploration and mining industry is unusual because the primary exploration targets are near-vertical kimberlite pipes that often are detected using magnetic and electromagnetic techniques. Subhorizontal dykes and sills do exist but they are poor potential field targets and have not been discovered by these techniques. However, one sub-horizontal structure, the Snap Lake dyke, was discovered in 1997 in the Archean Slave geological province of the Northwest Territories, Canada by tracking indicator minerals in the glacial till overburden. The Snap Lake dyke is a thin, dipping sheet that extends over at least 25 square km and plunges at approximately 15 degrees. The intrusion is richly diamondiferous and currently in the permitting stage for development of an underground mine. Its discovery heightened industry interest in dykes and sills, both in terms of their potential economic value and the information they yield regarding kimberlite emplacement. Since seismic reflection methods are especially well suited for mapping subhorizontal structures, dykes and sills have the potential to be excellent seismic targets. As a result, the Snap Lake seismic program was carried out to evaluate the seismic reflection method as a tool for exploration and deposit characterization of subhorizontal kimberlite intrusions. Snap Lake provides a superb test site for such a study because the dyke's gross geometry and composition have been determined through a substantial drilling program. Prior to the seismic field experiment, drill-core samples from the kimberlite and host rocks were used to measure P velocities and densities. These data were used to generate finite-difference and reflectivity

  17. Petrogenesis of the Mesoproterozoic (1.23 Ga) Sudbury dyke swarm and its questionable relationship to plate separation

    NASA Astrophysics Data System (ADS)

    Shellnutt, J. G.; Macrae, N. D.

    2012-01-01

    The Mesoproterozoic (~1.23 Ga) Sudbury dyke swarm was emplaced at equatorial latitudes and cross-cuts the Grenville, Southern and Superior Provinces of the Canadian Shield. The dyke swarm has been linked to the break-up of the Mesoproterozoic supercontinent Columbia (1.8 to 1.3 Ga). The Sudbury dykes are alkaline olivine diabases that extend ~300 km to the W and NW from the Grenville Front. Major element trends and MELTS modeling indicate fractional crystallization of olivine and plagioclase. Detailed mineral chemical analyses across a 90-m-wide dyke shows a symmetric M-shaped pattern indicating vertical flow differentiation. The highest measured Fo value of olivine from the chilled margin of one dyke is 70, suggesting the parental magmas of the dykes were evolved. Unlike other dykes of the Canadian Shield, the Sudbury dykes do not show significant chemical variation across the length of the swarm. The Sudbury dykes have high Sr/Y (>10), La/YbN (>5) and Sm/YbPM (>2.4) values indicating they originated from a garnet-bearing source. The low Th/Nb (<1.5) values contrast with the low Nb/La (<0.6) and La/Ba (~0.4) values, suggesting a possible lithospheric mantle or subduction-modified mantle source. In the context of Grenvillian tectonics, the Sudbury dykes intruded the Laurentian craton and parautochthonous rocks. The dykes occupy pre-existing west to northwest trending faults, suggesting that they exploited regional structural heterogeneities during the closure of the Elzevir basin (i.e., 1,250 to 1,190 Ma). The alkaline composition, limited spatial-chemical variation, volume, geometry and regional geological context suggest that the dykes are not likely related to a mantle plume or the break-up of a supercontinent.

  18. Using 2D and 3D Modeling to Infer the Depth of the Okavango Dyke Swarm

    NASA Astrophysics Data System (ADS)

    Dailey, M. K.; Mortimer, D.; Atekwana, E. A.

    2009-12-01

    The 179 Ma N110°-striking Okavango Dyke swarm (ODS) extends from southern Zimbabwe for approximately 1500 km northwest into Namibia. The emplacement of dyke swarms is typically associated with the initiation of continental breakup and has been suggested that ODS was emplaced during the breakup of Gondwana along an existing zone of weakness. However, the understanding of how these giant dyke swarms are emplaced over large distances for hundreds of kilometers is limited- do these giant dike swarms propagate from a single source for hundreds of kilometers or do they propagate from sub-crustal magma chambers along a zone of weakness? To address these questions we investigated the ODS in northern Botswana. The dyke swarm is exposed at the surface in the east close to its origin but is buried in the northwest within the Okavango Rift Zone. Using airborne magnetic and ground gravity survey data along with rock property data from the exposed sections, 2D and 3D models were created in order to determine the depth of the dyke swarm. Initially several 2D models were used to test hypothesis of varying depths and rock parameters. The 2D models were then used to ‘seed’ the 3D models with similar density, susceptibility, and depth parameters. The dykes appear to have relatively shallow and finite depths, in the range of 2 to 5 km deep. These results are consistent with a lateral emplacement stemming from the failed triple junction and thus ruling out an infinite depth extent which would have been the case if the dykes were propagated vertically from sub-crustal magma chambers.

  19. 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…

  20. Medicinal plants from swidden fallows and sacred forest of the Karen and the Lawa in Thailand

    PubMed Central

    2013-01-01

    Background Many ecosystem services provided by forests are important for the livelihoods of indigenous people. Sacred forests are used for traditional practices by the ethnic minorities in northern Thailand and they protect these forests that are important for their culture and daily life. Swidden fallow fields are a dominant feature of the agricultural farming landscapes in the region. In this study we evaluate and compare the importance of swidden fallow fields and sacred forests as providers of medicinal plants among the Karen and Lawa ethnic minorities in northern Thailand. Methods We made plant inventories in swidden fallow fields of three different ages (1–2, 3–4, 5–6 years old) and in sacred forests around two villages using a replicated stratified design of vegetation plots. Subsequently we interviewed the villagers, using semi-structured questionnaires, to assess the medicinal use of the species encountered in the vegetation survey. Results We registered a total of 365 species in 244 genera and 82 families. Of these 72(19%) species in 60(24%) genera and 32(39%) families had medicinal uses. Although the sacred forest overall housed more species than the swidden fallow fields, about equal numbers of medicinal plants were derived from the forest and the fallows. This in turn means that a higher proportion (48% and 34%) of the species in the relatively species poor fallows were used for medicinal purposes than the proportion of medicinal plants from the sacred forest which accounted for 17–22%. Of the 32 medicinal plant families Euphorbiaceae and Lauraceae had most used species in the Karen and Lawa villages respectively. Conclusion Sacred forest are important for providing medicinal plant species to the Karen and Lawa communities in northern Thailand, but the swidden fallows around the villages are equally important in terms of absolute numbers of medicinal plant species, and more important if counted as proportion of the total number of species in a

  1. Mafic Dykes from the Southwest Coast of India: Palaeomagnetism and tectonic implications

    NASA Astrophysics Data System (ADS)

    Joseph, M.; Perrin, M.; Radhakrishna, T.; Camps, P.; Balasubramonium, G.; Punoose, J.

    2009-04-01

    Late Cretaceous magmatism, south of the Deccan Traps, is widely distributed in the south west coast of India, mainly in the form of dyke intrusions. Most prominent dykes were emplaced around 70-65 Ma and are distributed in central Kerala, north Kerala and Goa. The strike trend of these dykes is NW-SE in central Kerala, whereas two orthogonal directions with NW-SE and NE-SW trends are found in north Kerala. In Goa region, they are mostly perpendicular to the coast. A subordinate magmatism, 90-85 Ma in age, is also traced in Agali and in the St. Mary Group of Islands off the Malpe coast. This magmatism is coeval with the leucogabbro dykes in central and north Kerala. Samples were collected from fifteen dykes with NW-SE trend. Samples belonging to the older episode of magmatism include one dyke from Agali and two sites from Coconut Island of the St. Mary volcanics. Most of the doleritic dykes are fine to medium grained with typical mineral assemblages of plagioclase, augite, olivine, and Fe-Ti oxides. Olivine is often transformed to iddingsite. Fe-Ti oxides are found either as early inclusions within pyroxene or as interstitial and may constitute the late crystallization phases. Selected specimens from each site were subjected to low and high temperature susceptibility measurements to define the magnetic carriers and the thermal stability of the samples. They have indicated titanomagnetite as the main carrier of magnetization. Palaeomagnetic measurements were carried out by detailed step-wise alternating field and thermal demagnetizations. After removal of sometime significant secondary components of magnetization, characteristic remanent magnetizations could be defined for most samples and mean directions of magnetization were obtained for twelve sites. Six of these sites come from the 70-65 Ma dykes, three being of reverse polarity with a mean direction of (D/I = 139/62) and a mean pole (Lat/Long = -26/101) and three yielding normal polarity (D/I = 340/-68 and Lat

  2. Board chairman John Makel on cutting services versus diversification. Interview by Karen Gardner.

    PubMed

    Makel, J

    1990-01-01

    John Makel, chairman of the board of the Memorial Health Alliance of Mount Holly, NJ, and vice-president and regional trust office manager, First Fidelity Bank, NA-New Jersey, Moorestown, began his tenure on the board of the Memorial Hospital of Burlington County, NJ, in 1975. He has been chairman of the alliance since 1983. Makel has been involved in diversification and divestment decisions since 1979, when the alliance was formed. It now includes a 402-bed acute care hospital--the Memorial Hospital of Burlington County--a 120-bed long-term care facility, and a home health care agency that makes approximately 70,000 home care visits a year The alliance's 30-member board, under the active leadership of a 13-member executive committee, governs each of the three affiliates. Recently, Trustee managing editor Karen Gardner talked with Makel to learn how the board has approached the difficult decisions involved in cutting services versus diversification.

  3. Karen Horney's "resigned person" heralds DSM-III-R's borderline personality disorder.

    PubMed

    Muller, R J

    1993-01-01

    It is shown here that what Karen Horney called the resignation solution to the problem of basic anxiety leads to psychopathology very similar to DSM-III-R's borderline personality disorder (BPD). Both the "resigned person" and the borderline personality show instability of self-image, social relationships, and mood, and live out the associated deficits with similar styles. While not specifically using the term "splitting", Horney showed how alternating expansive and self-effacing trends can coexist in the resigned person, and how these oscillations in self-other-world constitution influence the resigned person's behavior in a way similar to borderline splitting. Horney's descriptive and psychodynamic analysis of the resignation phenomenon elaborates and gives additional credibility to DSM-III-R's BPD as a diagnostic category.

  4. The structure of the Okavango giant mafic dyke swarm in the Karoo magmatic province of North Botswana

    NASA Astrophysics Data System (ADS)

    Le Gall, B.; Tshoso, G.; Tiercelin, J. J.; Dyment, J.; Aubourg, C.; Feraud, G.; Jourdan, F.; Bertrand, H.

    2003-04-01

    Field structural measurements combined to magnetic dataset (including both aero- and ground magnetic records) allow a systematic investigation of the structure of the Okavango giant (2000 x 100 km) mafic dyke swarm in N Botswana. The results are discussed about a 55 km-long projected section lying perpendicular to the densest zone of the swarm and cutting through Proterozoic granito-gneissic host-rocks. A total dyke population of 423 (magnetic records) or 171 (field data) individual intrusions is identified and consists principally of basalts and dolerites. New high-precision dating (Jourdan et al., this congress) demonstrates the composite nature of the Okavango swarm that includes Karoo dykes (70%) and additional (30%) Proterozoic intrusions. The two dyke populations lie with a similar strike and show no discriminant petro-structural features in the field. These new results make it difficult 1) discriminating Karoo versus Proterozoic dyke groups within the total population derived from magnetics, and 2) defining their respective structural characteristics. About the Karoo dyke population (360 intrusions), field structural observations help to constrain the statistical analysis of some of its geometrical parameters, such as the strike (N110°E), dip (vertical), lenght (ca. 5 km), thickness (18-20 m), spacing, or direction of dyke opening. The dyke-induced crustal dilatation is estimated to 6-10% across the 55 km-long reference section. Structural observations also emphazise the control exerted by preexisting basement fabrics (brittle joints and dykes) on Karoo dyke emplacement. Synmagmatic deformation is restricted to wall-parallel tensile joint networks with no evidence for extensional faulting. The Karoo part of the Okavango giant dyke swam is inferred to have been emplaced under an unidirectional extensional stress field (N70°E). Furthermore, analyzing the anisotropy of magnetic susceptibility of a number of dykes (Tshoso et al., this congress) indicates an

  5. Controls on sill and dyke-sill hybrid geometry and propagation in the crust: The role of fracture toughness

    NASA Astrophysics Data System (ADS)

    Kavanagh, J. L.; Rogers, B. D.; Boutelier, D.; Cruden, A. R.

    2017-02-01

    Analogue experiments using gelatine were carried out to investigate the role of the mechanical properties of rock layers and their bonded interfaces on the formation and propagation of magma-filled fractures in the crust. Water was injected at controlled flux through the base of a clear-Perspex tank into superposed and variably bonded layers of solidified gelatine. Experimental dykes and sills were formed, as well as dyke-sill hybrid structures where the ascending dyke crosses the interface between layers but also intrudes it to form a sill. Stress evolution in the gelatine was visualised using polarised light as the intrusions grew, and its evolving strain was measured using digital image correlation (DIC). During the formation of dyke-sill hybrids there are notable decreases in stress and strain near the dyke as sills form, which is attributed to a pressure decrease within the intrusive network. Additional fluid is extracted from the open dykes to help grow the sills, causing the dyke protrusion in the overlying layer to be almost completely drained. Scaling laws and the geometry of the propagating sill suggest sill growth into the interface was toughness-dominated rather than viscosity-dominated. We define KIc* as the fracture toughness of the interface between layers relative to the lower gelatine layer KIcInt / KIcG. Our results show that KIc* influences the type of intrusion formed (dyke, sill or hybrid), and the magnitude of KIcInt impacted the growth rate of the sills. KIcInt was determined during setup of the experiment by controlling the temperature of the upper layer Tm when it was poured into place, with Tm < 24 °C resulting in an interface with relatively low fracture toughness that is favourable for sill or dyke-sill hybrid formation. The experiments help to explain the dominance of dykes and sills in the rock record, compared to intermediate hybrid structures.

  6. Formation conditions of leucogranite dykes and aplite-pegmatite dykes in the eastern Mt. Capanne plutonic complex (Elba, Italy): fluid inclusion studies in quartz, tourmaline, andalusite and plagioclase

    NASA Astrophysics Data System (ADS)

    Bakker, Ronald J.; Schilli, Sebastian E.

    2016-02-01

    Leucogranite and aplite-pegmatite dykes are associated with the Mt. Capanne pluton (Elba) and partly occur in the thermally metamorphosed host rock (serpentinites). Crystallization conditions of these dykes in the late magmatic-hydrothermal stage are estimated from fluid inclusion studies and mineralogical characterisation, obtained from detailed microthermometry, Raman spectroscopy, and electron microprobe analyses. Fluid inclusion assemblages are analysed in andalusite, quartz, and plagioclase from the leucogranite dykes, and in tourmaline and quartz from the aplite-pegmatite dykes. The fluid inclusion assemblages record multiple pulses of low salinity H2O-rich magmatic and reduced metamorphic fluid stages. Magmatic fluids are characterized by the presence of minor amounts of CO2 and H3BO3, whereas the metamorphic fluids contain CH4 and H2. The highly reduced conditions are also inferred from the presence of native arsenic in some fluid inclusions. Several fluid inclusion assemblages reveal fluid compositions that must have resulted from mixing of both fluid sources. In leucogranite dykes, magmatic andalusite contains a low-density magmatic CO2-rich gas mixture with minor amounts of CH4 and H2. Accidentally trapped crystals (mica) and step-daughters (quartz and diaspore) are detected in some inclusions in andalusite. The first generation of inclusions in quartz that crystallized after andalusite contains a highly reduced H2O-H2 mixture and micas. The second type of inclusions in quartz from the leucogranite is similar to the primary inclusion assemblage in tourmaline from the aplite-pegmatite, and contains up to 4.2 mass% H3BO3, present as a sassolite daughter crystal or dissolved ions, in addition to a CO2-CH4 gas mixture, with traces of H2, N2, H2S, and C2H6. H2O is the main component of all these fluids ( x = 0.91 to 0.96) with maximally 7 mass% NaCl. Some accidentally trapped arsenolite and native arsenic are also detected. These fluids were trapped in the

  7. 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

  8. Dyke Intrusion and Arrest in Harrat Lunayyir, western Saudi Arabia, in April-July 2009

    NASA Astrophysics Data System (ADS)

    Jónsson, Sigurjón; Pallister, John; McCausland, Wendy; El-Hadidy, Salah

    2010-05-01

    Dyke intrusion in Harrat Lunayyir (also known as Harrat Al-Shaqah), one of the volcanic provinces in Saudi Arabia, caused numerous small to moderate-sized earthquakes and extensive surface faulting in April-July 2009. The most intensive earthquake activity took place on 17-20 May when six magnitude 4.6-5.7 earthquakes occurred, resulting in some structural damage and prompting the Saudi civil protection authorities to evacuate more than 30000 people from the area. While the earthquake activity significantly decreased after 20 May, it continued throughout June and July with a few earthquakes as large as magnitude ~4, before quieting down in August. Much of what we have learned about the activity comes from interferometric satellite radar (InSAR) observations and from analysis of the seismic data collected by a broadband seismic network that was installed soon after the earthquake swarm started in April. The InSAR data show that large-scale (40 km × 40 km) east-west extension of over 1 m took place as well as broad uplift amounting to over 40 cm. The center of the uplifted area was transected by northwest-trending graben subsidence of over 50 cm, bounded by a single fault to the southwest showing up to ~1 m of faulting and by multiple smaller faults and cracks to the northeast. The observed deformation is well explained with a near-vertical dyke intrusion and graben-bounding normal faulting. The strike of the model dyke is NNW-SSE, parallel to the Red Sea rift, and its volume is about 0.13 km3. The modeling suggests that the shallowest part of the dyke 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. The main graben-bounding surface fault, to the southwest of the dyke, grew from ~3 km to ~8 km with the magnitude 5.7 earthquake on 19 May. Soon after this event the overall earthquake activity dramatically declined. The faulting appears to have

  9. Fragments of the Archean Mantle in Ultramafic Dykes From Wawa, Ontario

    NASA Astrophysics Data System (ADS)

    Morissette, C. L.; Francis, D.

    2004-05-01

    The Wawa area of the Superior Province possesses numerous ultramafic dykes of Archean age that contain ultramafic nodules potentially representing samples of Archean mantle. Three different types of dykes can be distinguished, each of which hosts its own suite of xenoliths. The Sandor and BandOre dykes, located north of Wawa, exhibit overall compositional similarities with Phanerozoic shoshonite / minette suites. They are characterised by high Al2O3 and K2O contents, and are rich in biotite and chlorite. These two dykes contain rounded nodules, ranging in size from about 5 to 60 cm, composed mostly of actinolite and tremolite, which are interpreted to have been pyroxenites. They are ultrabasic to basic in composition, ranging in SiO2 from 43 to 55 wt%, have orthopyroxene / clinopyroxene ratios of approximately 1:1, and MgOs ranging from 80 to 88. Some xenoliths, however, have significantly high Al content (>11 wt%), and could very well represent recrystallized fragments of the host minette, or other gabbroic protolith. The second type of Archean dykes, located east of Wawa near Dalton, is more similar in composition to Group-II kimberlites. They are characterised by low Al2O3, but high SiO2 contents, and are composed of chlorite, serpentine and feldspar as the dominant mineral phases. This matrix hosts olivine pyroxenite xenoliths with orthopyroxene / clinopyroxene proportions of 2:1. The presence of a poikilitic texture and the vestiges of zoning in pseudomorphs after clinopyroxene indicates they were cumulates. Another nearby dyke is also similar in composition to type II kimberlites, but richer in SiO2. This dyke has feldspar, amphibole and serpentine as its dominant minerals and hosts ultramafic xenoliths that have almost completely been altered to serpentine, though some fresh olivine relicts remain. These xenoliths have the normative mineralogy of highly depleted harzburgite (<1.5 wt.% Al2O3) with MgOs between 88 and 93. A small variation in Ni compared to

  10. Geophysical characteristics of Aswa shear, Nagasongola discontinuity and ring dyke complex in Uganda

    NASA Astrophysics Data System (ADS)

    Ruotoistenmäki, Tapio

    2014-05-01

    During the years 2008-2012, the geology of most of Uganda was studied within the framework of the Sustainable Management of Mineral Resources Project (SMMRP). During the project, comprehensive airborne magnetic and radiometric surveys were flown over the entire country and geological, petrophysical, geochemical sampling, geological field studies and detailed geophysical field profiles were undertaken in selected sub-areas. This report concentrates on the geophysical properties of three major geophysical structures in the area considered during the project: the Pan-African (0.6-0.7 Ga) Aswa shear zone and Nagasongola discontinuity (suture), and the 1.36 Ga Uganda-Tanzania semi-circular ‘ring dyke' complex. The geophysical profiles across the Aswa shear indicate that the fault zone dips steeply, at about 60° to NE. The structure represents a magnetic, gravimetric (density), radiometric and topographic discontinuity, all diminishing from SW to NE across the zone. The zone is also characterized by complex radiometric anomalies. A schematic reconstruction of the evolution of the Aswa shear zone on the magnetic map suggests a nearly 60 km sinistral horizontal component of displacement along the zone. The Nakasongola zone is another distinct magnetic, gravimetric and radiometric discontinuity, interpreted to represent a collision (suture) zone, where the northern, low-magnetic block has been thrust over the southern, denser and more magnetic block. Modeling of gravity and magnetic data are consistent with a geometry in which the southern, magnetic and high-density block dips gently to great depth beneath the northern block. Bedrock exposures in both the Aswa shear zone and Nagasongola zone areas indicate a very protracted and complex history of tectonic processes commencing in the Archaean-Paleoproterozoic era and culminating in Pan-African orogenies. Both, the Aswa shear zone and Nagasongola discontinuity are cut by continuous younger dykes that show no signs of

  11. Geometry and emplacement of the Late Cretaceous mafic dyke swarms on the islands in Zhejiang Province, Southeast China: Insights from high-resolution satellite images

    NASA Astrophysics Data System (ADS)

    Chen, Ning-hua; Dong, Jin-jin; Chen, Jian-yu; Dong, Chuan-wan; Shen, Zhong-yue

    2014-01-01

    The geology of Zhejiang coastal area in Southeast China is characterized by numerous Late Mesozoic intrusive rocks and widespread mafic dyke swarms, which indicate continental lithospheric extensional events during the Jurassic and Cretaceous. This work is focused on using multisource high-resolution remote sensing images (Worldview2, Geoeye1 and Quickbird2) to identify the geometry, morphology and location of previously undocumented and poorly understood dyke swarms exposed on the islands in Zhejiang Province. The geometry of each dyke is described by its strike, length and thickness. The spatial distribution of the dyke density and crustal dilation are obtained based on the statistics of 774 extracted mafic dykes. Field surveys are performed in some islands in order to analyze the detailed geometric features and assess the interpretative accuracy. The spectral measurement and analysis of mafic dykes are performed as well for remote sensing imagery processing and lithological interpretation. The results show that the frequency distributions of the length and thickness of dykes follow power law curves. The maximum and mean dyke thicknesses are 11.2 m and 1.43 m, respectively. The crustal dilation of the islands ranges from 0.09% to 7.4%. From the north to the south islands, the dilation decreases gradually. The dyke frequency and density have the same distribution as the dilation. According to 40Ar-39Ar age (Zhongshanjie archipelago) and U-Pb zircon age (Sijiao Island) of the mafic dyke, the dyke swarms on the eastern Zhejiang islands emplaced at around 87-97 Ma. The cross-cutting relationships of dykes and host rocks show that the mafic dyke swarms have close spatial correlations with granite. The dykes stretch in various directions whereas the NE-trending dykes dominate. Our research reveals four intrusive events that imply the crustal extension and intermittent variation of the regional stress field in the coastal area of southeastern China in the Late

  12. Magma flow pattern in dykes of the Azores revealed by anisotropy of magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Moreira, M. A.; Geoffroy, L.; Pozzi, J. P.

    2015-02-01

    The localization of magma melting areas at the lithosphere bottom in extensional volcanic domains is poorly understood. Large polygenetic volcanoes of long duration and their associated magma chambers suggest that melting at depth may be focused at specific points within the mantle. To validate the hypothesis that the magma feeding a mafic crust, comes from permanent localized crustal reservoirs, it is necessary to map the fossilized magma flow within the crustal planar intrusions. Using the AMS, we obtain magmatic flow vectors from 34 alkaline basaltic dykes from São Jorge, São Miguel and Santa Maria islands in the Azores Archipelago, a hot-spot related triple junction. The dykes contain titanomagnetite showing a wide spectrum of solid solution ranging from Ti-rich to Ti-poor compositions with vestiges of maghemitization. Most of the dykes exhibit a normal magnetic fabric. The orientation of the magnetic lineation k1 axis is more variable than that of the k3 axis, which is generally well grouped. The dykes of São Jorge and São Miguel show a predominance of subhorizontal magmatic flows. In Santa Maria the deduced flow pattern is less systematic changing from subhorizontal in the southern part of the island to oblique in north. These results suggest that the ascent of magma beneath the islands of Azores is predominantly over localized melting sources and then collected within shallow magma chambers. According to this concept, dykes in the upper levels of the crust propagate laterally away from these magma chambers thus feeding the lava flows observed at the surface.

  13. Evidences for multiple remagnetization of Proterozoic dykes from Iguerda inlier (Anti-Atlas Belt, Southern Morocco)

    NASA Astrophysics Data System (ADS)

    Neres, Marta; Silva, Pedro F.; Ikene, Moha; Martins, Sofia; Hafid, Ahmid; Mata, João; Almeida, Francisco; Youbi, Nasrrddine; Boumehdi, Ahmed

    2016-04-01

    Paleomagnetic data able to constrain the paleoposition of the West African Craton (WAC) during Paleo-Mesoproterozoic are absent, mainly due to gaps on the sedimentary record and intense remagnetizations. Dykes that intrude several Proterozoic inliers of WAC in the Anti-Atlas Belt (southern Morocco) have recently been subjected to geochronological studies, which revealed ages between Paleoproterozoic and early Neoproterozoic. Therefore, these dykes represent a window of opportunity for paleomagnetic studies aiming to infer about the paleoposition of WAC during Proterozoic. On this scope we conducted a paleomagnetic study on seven Proterozoic dykes of the Iguerda inlier. We determined the paleomagnetic directions and evaluated their meaning by rock magnetic and mineral analyses, complemented by petrographic observations. Results revealed that these rocks record the presence of a complex history of remagnetization events, mostly assigned to several Phanerozoic thermal/chemical events. In particular, we found components assigned to the late stages of Pan African orogeny (s.l.), to the Late Carboniferous Variscan orogeny, and to more recent events. The recognized remagnetization processes are related to widespread metamorphic events under greenschist facies followed by low-temperature oxidation, both responsible for the formation of new magnetic phases (magnetite and hematite). The primary (magmatic) thermo-remanent magnetization of the dykes was obliterated during these events through multiple thermal and chemical remagnetizations. For only one dyke the presence of primary magnetization is possible to infer, though not to confirm, and would place WAC at an equatorial position around 1750 Ma. The authors wish to acknowledge FCT (Portugal) - CNRST (Morocco) bilateral agreement for its major contribution without which this work wouldn't be possible. Publication supported by project FCT UID/GEO/50019/2013 - Instituto Dom Luiz.

  14. "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.

  15. Dyke swarms and their role in the genesis of world-class gold deposits: Insights from the Jiaodong peninsula, China

    NASA Astrophysics Data System (ADS)

    Li, Lin; Li, Sheng-Rong; Santosh, M.; Li, Qing; Gu, Yue; Lü, Wen-Jie; Zhang, Hua-Feng; Shen, Jun-Feng; Zhao, Guo-Chun

    2016-11-01

    Jiaodong peninsula, located at the southeastern margin of the North China Craton, is well known for its rich endowment of super-large gold deposits. This region is also characterized by hundreds of intermediate - mafic dykes that cluster into several dyke swarms. In this study, we present zircon U-Pb ages which show that the timing of dyke emplacement as ca. 120 Ma, which followed the crystallization of the (quartz-) diorite porphyry at ca. 130 Ma. These ages coincide with the peak ages reported for magmatism and metallogeny in the central North China Craton. The various ages (2450-2570 and 154 Ma) from the inherited zircon crystals in these rocks suggest that substantial lower to middle crustal basement rocks and Jurassic granitoids were involved during dyke emplacement. The dyke swarms, varying between alkaline and subalkaline, are compositionally low-Si low-Ti lamprophyre and low-Si high-Ti dolerite porphyry in the western of the Jiaodong peninsula, whereas those in the eastern part are composed of both high-Si low-Ti and low-Si high-Ti lamprophyres. These features imply multiple sources for the dykes from convective asthenospheric mantle to ancient enriched lithospheric mantle with magma generation at different depths involving mixture of slab-derived hydrous fluids. The source magmas of the dykes were hydrous and enriched in volatiles as well as ore components, and their evolution occurred under high oxygen fugacity conditions. The relatively rapid emplacement and cooling of the dyke systems enabled the migration of fluids into ore-controlling faults or fractures. We envisage that the dyke swarms played an important role in generating the world-class gold mineralization of Jiaodong.

  16. Ford Van Dyke: Compressed Air Management Program Leads to Improvements that Reduce Energy Consumption at an Automotive Transmission Plant

    SciTech Connect

    2010-06-25

    Staff at the Ford Van Dyke Transmission Plant in Sterling Heights, Michigan, have increased the efficiency of the plant’s compressed air system to enhance its performance while saving energy and improving production.

  17. Dyke Swarms in Southeastern British Columbia: Mineralogical and Geochemical Evidence for Emplacement of Multiple Magma Types During Orogenic Collapse

    NASA Astrophysics Data System (ADS)

    Freeman, M.; Owen, J. P.; Hoskin, P. W.

    2009-05-01

    Eocene dyke swarms in southeastern British Columbia provide an important record of the tectonic and magmatic history of the Cordillera following orogenic collapse. New field mapping, petrographic, and geochemical data is presented for a swarm of more than thirty dykes located near the mining town of Trail, B.C. Detailed field mapping revealed that individual dykes are highly diverse, both in composition and morphology. As a group, the dykes trend northwest (average strike of 338 degrees) and dip steeply to the southwest. Their average thickness is approximately 1.5m, with a range from 4.5m to less than 1cm. Three sub-parallel dykes were mapped for a length of 2km, and exhibit irregularities in their form such as branching and offshoots that follow fractures in the country rock. Thin-section analysis shows a wide variety of rock types within the swarm, including: micro-quartz syenite, micro-syenite, micro-monzonite, latite, basalt, basaltic andesite, and lamprophyre. Texturally, these samples are consistently porphyritic and partially altered to chlorite and sericite. This alteration commonly occurs in concentric rims around phenocrysts. The samples are typically intergranular, although some display trachytic texture. Whole-rock geochemistry shows that the dykes have a wide range in composition, with SiO2 between 76.45 wt.% and 45.15 wt.% and MgO between 0.13 wt.% and 13.16 wt.%. The results also revealed that one dyke has very high values of Ni (430 ppm), Cr (1420 ppm), and Co (50 ppm), giving it a fairly primitive composition. Harker diagrams and trace element plots show three distinct groups: mafic calc-alkaline dykes, felsic calc- alkaline dykes, and minette lamprophyres. The felsic dykes are characterized by negative Eu and Sr anomalies suggesting fractionation of plagioclase feldspar, as well as pronounced negative P and Ti anomalies. The minettes are enriched in LILE and depleted in HSFE relative to the mafic dykes. The three groups do not appear to be

  18. 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

  19. The death of a Strombolian eruption: Evidence for dyke drainage from Red Crater, Tongariro volcano, New Zealand

    NASA Astrophysics Data System (ADS)

    Wadsworth, F. B.; von Aulock, F. W.; Kennedy, B.; Branney, M.; Bardsley, C. J.

    2010-12-01

    How volcanic eruptions stop is poorly understood. We present data from a dyke in the wall of Red Crater, Tongariro volcano, NZ, that record the closing stages of an eruption. The 1.85ka eruption began with andesite effusion followed by Strombolian eruption of basaltic andesite. It terminated with withdrawal of basaltic andesite from a shallow level dyke accompanied by a last gasp of phreatic explosivity. The dyke is twice as wide within the upper poorly consolidated scoria as it is within underlying better consolidated brecciated lava. In lower parts near the boundary between the lava breccia and scoria the dyke is full, whereas at higher levels both dyke marginal zones are preserved with a spectacular evacuated interior. Detailed field mapping and textural analysis of crystallinities and vesicularities using >5mm vesicles, reveal three texturally distinct facies. (1) A glassy marginal facies with 12% vesicularity, margin-parallel flow banding and fabric defined by a preferred orientation of small phenocrysts (20-30% vol.). (2) A fully crystalline lower central zone with phenocrysts (50% vol.) randomly orientated and variably elongate vesicles (32% vol.). (3) An upper, almost completely crystalline central facies with subhorizontal flow banding arranged in en-echelon arrays, subhorizontally orientated phenocrysts (45-50% vol.) and patchy development of sub-spherical vesicles (vesicularity varies from 18-24% vol.). Coating the evacuated dyke interior is 1-2m finely laminated, fine-grained palagonitized ash. We interpret the three facies to correspond to three phases of magma movement. Facies 1 is related to rapid freezing against the dyke margins during vertical eruption. Facies 2 relates to a waning eruption during which the dyke widened. Facies 3 records the draining body of magma in retreat, during which the magma level stepped inward, preserving subhorizontal, 0.2-0.5m wide “bathtub rings” on the interior wall of the dyke marginal zone. The rings occur 2m

  20. Measuring Local Strain Rates In Ductile Shear Zones: A New Approach From Deformed Syntectonic Dykes

    NASA Astrophysics Data System (ADS)

    Sassier, C.; Leloup, P.; Rubatto, D.; Galland, O.; Yue, Y.; Ding, L.

    2006-12-01

    At the Earth surface, deformation is mostly localized in fault zones in between tectonic plates. In the upper crust, the deformation is brittle and the faults are narrow and produce earthquakes. In contrast, deformation in the lower ductile crust results in larger shear zones. While it is relatively easy to measure in situ deformation rates at the surface using for example GPS data, it is more difficult to determinate in situ values of strain rate in the ductile crust. Such strain rates can only be estimated in paleo-shear zones. Various methods have been used to assess paleo-strain rates in paleo-shear zones. For instance, cooling and/or decompression rates associated with assumptions on geothermic gradients and shear zone geometry can lead to such estimates. Another way to estimate strain rates is the integration of paleo-stress measurements in a power flow law. But these methods are indirect and imply strong assumptions. Dating of helicitic garnets or syntectonic fibres are more direct estimates. However these last techniques have been only applied in zones of low deformation and not in major shear zones. We propose a new direct method to measure local strain rates in major ductile shear zones from syntectonic dykes by coupling quantification of deformation and geochronology. We test our method in a major shear zone in a well constrained tectonic setting: the Ailao-Shan - Red River Shear Zone (ASRRsz) located in SE Asia. For this 10 km wide shear zone, large-scale fault rates, determined in three independent ways, imply strain rates between 1.17×10^{-13 s-1 and 1.52×10^{-13 s-1 between 35 and 16 Ma. Our study focused on one outcrop where different generations of syntectonic dykes are observed. First, we quantified the minimum shear strain γ for each dyke using several methods: (1) by measuring the stretching of dykes with a surface restoration method (2) by measuring the final angle of the dykes with respect to the shear direction and (3) by combining the two

  1. 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.

  2. Geochronology, Geochemistry and Petrogenesis of the Intermediate and Acid Dykes in Linzhou Basin, Southern Tibet

    NASA Astrophysics Data System (ADS)

    Dong, M.; Zhao, Z.; Zhu, D. C.; Dong, G.; Mo, X.

    2015-12-01

    The Linzizong volcanic succession (also called Linzizong Group, ~65-45 Ma), which occurred in southern Gangdese magmatic belt in response to the collision processes between India and Eurasia continents, have been well studied in the Linzhou Basin, to the northeast of Lhasa. Our research obtains some new results of zircon U-Pb, Hf isotopic data, and whole rock major and trace elements geochemical data of the intermediate (diorite porphyry) to acid (granite porphyry) dykes intruded into the Linzizong volcanics in Linzhou Basin. These dykes intruded into Dianzhong and Nianbo formations of Linzizong Group. All the samples are sub-alkaline, varying from calc-alkaline to high-K calc-alkaline series. They are peraluminous (A/CNK>1.1). The diorite porphyry, intruded in 62.4Ma with positive zircon Hf isotopes (ɛHf(t)=+5.1~+7.6), have similar composition to the andesitic rocks from Dianzhong Formation. The granite porphyries, intruded between 55.1Ma and 61.1Ma, with ɛHf(t) ranging from -1.1 to +10.4, have comparable composition with the rhyolitic Nianbo Formation. A series of evidences, including: (1) the samples have positive, mantle-like Hf feature (average ɛHf(t)=+5.9 of 86 samples); (2) wide-range variation of ɛHf(t) in samples (3.5~8.8 ɛ units in the four granite porphyries), which implying an inhomogeneous source regions; (3) magma-mixing trend in the plots of FeOT against MgO, suggesting that the magma-mixing processes that have taken place in the southern Gangdese belt, can also be applied to explain the origin of these dykes in Linzhou Basin. The dykes intruded coeval or shortly later than their equivalent volcanic rocks (Dianzhong and Nianbo formations), are in the transitional settings from subduction of Tethyan oceanic crust to the collisional between India and Eurasia continents.

  3. Integrating WorldView-2 imagery and terrestrial LiDAR point clouds to extract dyke swarm geometry: Implications for magma emplacement mechanisms

    NASA Astrophysics Data System (ADS)

    Ni, Nina; Chen, Ninghua; Chen, Jianyu; Liu, Mingliang

    2016-01-01

    Dyke geometries are useful indicators of the palaeostress field during magma emplacement. In this paper, we present a multi-scale extraction method of dyke geometries by integrating WorldView-2 (WV2) imagery and terrestrial light detection and ranging (LiDAR) data. Color composite and fusion WV2 images with 0.5-m resolution were generated by using the Gramm-Schmidt Spectral Sharpening approach, which facilitates the discrimination of dyke swarms and provides the ability to measure the orientation, exposed length, and thickness of dykes in sub-horizontal topographic exposures. A terrestrial laser scanning survey was performed on a sub-vertical exposure of dykes to obtain LiDAR data with point spacing of ~ 0.02 m at 30 m. The LiDAR data were transformed to images for extracting dyke margins based on image segmentation, then the dyke attitudes, thicknesses, and irregularity of dyke margins were measured according to the points on dyke margins. This method was applied at Sijiao Island, Zhejiang, China where late Cretaceous mafic dyke swarms are widespread. The results show that integrating WV2 imagery and terrestrial LiDAR improves the accuracy, efficiency, and objectivity in determining dyke geometries in two and three dimensions. The ENE striking dykes are dominant, and intruded the host rock (mainly granite) with sub-vertical dips. Based on the aspect ratios of the dykes, the magmatic overpressure was estimated to be less than 11.5 MPa, corresponding to a magma chamber within 6.6 km in the lithosphere.

  4. Monitoring dyke injection and strain field evolution using shear-wave splitting.

    NASA Astrophysics Data System (ADS)

    Kendall, J.-M.; Verdon, J. P.; Keir, D.; Baird, A.

    2012-04-01

    Magma storage and dyke injection in the shallow crust is a fundamental process in rifting and volcanic environments. The dyking will tend to align with directions of maximum compressive stress, and the associated aligned fracturing and melt migration provides a very effective means of generating seismic anisotropy. Observations of shear-wave splitting provide one of the most unambiguous indicators of such anisotropy. As such, shear-wave splitting can be used to monitor the evolving strain field in volcanic and rifting environments. Here we apply lessons learned from monitoring fracture propagation during the hydraulic stimulation of tight-gas reservoirs. In a number of experiments we observe spatial and temporal variations in shear-wave splitting magnitude and orientation. We invert shear-wave observations for fracture properties, including the tangential and normal compliance, the ratio of which is a good indicator of fluid flow and permeability. Frequency dependent affects can be also used to indicate the length scales of the causative cracks or fractures. We apply these insights to microseismic data recently acquired across the volcanically active Afar triple junction in Ethiopia. The pattern of S-wave splitting in Afar is best explained by anisotropy from deformation-related structures, with the dramatic change in splitting parameters into the rift axis from the increased density of dyke-induced faulting combined with a contribution from oriented melt pockets near volcanic centres. The results help in our understanding of the role of melt in strain accommodation in rifting and volcanic environments.

  5. Dyking at EPR 16°N hypermagmatic ridge segment: Insights from near-seafloor magnetics

    NASA Astrophysics Data System (ADS)

    Szitkar, Florent; Dyment, Jérôme; Le Saout, Morgane; Honsho, Chie; Gente, Pascal

    2016-11-01

    High-resolution, near-seafloor magnetic data have been acquired over the 16°N hypermagmatic segment of the East-Pacific Rise using an Autonomous Underwater Vehicle. This survey proves to be ideal to test the relative efficiency of various inversion methods applied to data acquired at a more or less constant altitude above the seafloor. Unlike other methods, a recently published Bayesian inversion preserves the short wavelengths and allows for the resolution of a high-resolution reduced-to-the-pole magnetic anomaly. This anomaly unveils the presence of several laterally adjacent dykes associated with individually separated Axial Summit Troughs. The observation of such anomalies, and therefore of shallow dykes, confirms the hypermagmatic character of the segment in a location where complex magma chambers have been imaged in seismic reflection studies. Variable intensity of the magnetic anomalies reflects the depth of the dyke swarms and, ultimately, the timing and style of eruptive events, helping to constrain the spreading axis evolution.

  6. The influence of inherited structures on dyke emplacement during Gondwana break-up in southwestern Africa

    NASA Astrophysics Data System (ADS)

    Will, Thomas; Frimmel, Hartwig

    2013-04-01

    A kinematic analysis of Cretaceous and pre-Cretaceous faulting and fracturing was carried out along the west coast of Southern Africa extending from the greater Cape Town area to the Orange River and beyond into southern Namibia. This study was augmented by the geometric analysis of mainly Cretaceous mafic dykes exposed from SW Angola to the southern tip of Africa. The kinematic analysis shows that the Cretaceous rifting event that led to the opening of the modern South Atlantic was largely controlled by NW-SE and NE-SW-striking structures. In the coastal areas of South Africa the Cretaceous deformation was dominated by NE-SW extension, whereas a general E-W-oriented extension prevailed further north. Analysis of reverse and strike-slip faulting in the Gariep and western Saldania Belts shows that the Pan-African constrictional deformation in South Africa was mainly controlled by ENE-WSW- to ESE-WNW-oriented shortening. Further north, the geometry of the Odgen Rock Mylonites in Namibia is controlled by N-S-striking strike-slip faults. The geometric analysis of the orientation of the mafic dykes also points to an E-W-oriented extension direction in the coastal areas extending from southern Angola to Meob and Conception Bay in west-central Namiba and changes to a generally NE-SW-oriented extension along the west coast of South Africa. Further inland in the Damara Belt sensu strictu, the geometric analysis of dykes belonging to the Hentjes Bay-Outjo Dyke Swarm also indicates NE-SW-oriented extension but, in addition, also a strong component of NW-SE-directed extension controlled dyke emplacement. The results of this study suggest that Pan-African (or older) structural discontinuities were re-utilised during the opening of the South Atlantic in the Early Cretaceous. The extension directions associated with Cretaceous Gondwana break-up structures are subparallel to the Pan-African shortening orientations. The inherited structural anisotropies are generally parallel to

  7. The campsite dykes: A window into the early post-solidification history of the Skaergaard Intrusion, East Greenland

    NASA Astrophysics Data System (ADS)

    Holness, Marian B.; Richardson, Chris; Andersen, Jens C. Ø.

    2013-12-01

    The Skaergaard Intrusion of East Greenland is cut by several generations of dykes, the earliest of which is thought to have intruded shortly after solidification of the Skaergaard. Two ~ 6 m wide doleritic dykes from the earliest generation are exposed in the campsite area near Homestead Bay of the Skaergaard Peninsula. One of the dykes (the Campsite Dyke) locally contains abundant xenoliths of troctolitic cumulate. The other (the Plagioclase-phyric Dyke) contains abundant large plagioclase phenocrysts. Cross-cutting relationships between the two dykes are not exposed. The median clinopyroxene-plagioclase-plagioclase dihedral angle, Θcpp, in the Campsite Dyke is 88-89.5°, whereas that of the Plagioclase-phyric Dyke is 79°. Using an empirical relationship between Θcpp and the duration of crystallisation derived from dolerite sills, the observed Θcpp suggests that the Campsite Dyke is the older of the two, intruding the Skaergaard when it had cooled to 920-970 °C. The Plagioclase-phyric Dyke intruded later, once the Skaergaard had cooled below 670 °C. The troctolitic xenoliths divide into two separate groups. Type A xenoliths have microstructures similar to those of the Skaergaard Layered Series although mineral compositions are generally more primitive than those of the exposed cumulates - this type of xenolith is likely to have been derived from either deeper levels in the Skaergaard Intrusion or from a closely-related underlying magma chamber. One Type A xenolith has mineral compositions and Θcpp consistent with an origin in LZb of the Layered Series - this xenolith contains partially inverted pigeonite, suggesting that inversion of low-Ca pyroxene in the lower part of the Layered Series took place after the intrusion had completely solidified. Type B xenoliths are characterized by plagioclase containing large and abundant melt inclusions. Comparison with the microstructures of glassy crystalline nodules from Iceland points to a multi-stage cooling history

  8. 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

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. 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.

  14. Fault and dyke detectability in high resolution seismic surveys for coal: a view from numerical modelling*

    NASA Astrophysics Data System (ADS)

    Zhou, Binzhong 13Hatherly, Peter

    2014-10-01

    Modern underground coal mining requires certainty about geological faults, dykes and other structural features. Faults with throws of even just a few metres can create safety issues and lead to costly delays in mine production. In this paper, we use numerical modelling in an ideal, noise-free environment with homogeneous layering to investigate the detectability of small faults by seismic reflection surveying. If the layering is horizontal, faults with throws of 1/8 of the wavelength should be detectable in a 2D survey. In a coal mining setting where the seismic velocity of the overburden ranges from 3000 m/s to 4000 m/s and the dominant seismic frequency is ~100 Hz, this corresponds to a fault with a throw of 4-5 m. However, if the layers are dipping or folded, the faults may be more difficult to detect, especially when their throws oppose the trend of the background structure. In the case of 3D seismic surveying we suggest that faults with throws as small as 1/16 of wavelength (2-2.5 m) can be detectable because of the benefits offered by computer-aided horizon identification and the improved spatial coherence in 3D seismic surveys. With dykes, we find that Berkhout's definition of the Fresnel zone is more consistent with actual experience. At a depth of 500 m, which is typically encountered in coal mining, and a 100 Hz dominant seismic frequency, dykes less than 8 m in width are undetectable, even after migration.

  15. Left hemisphere and male sex dominance of cerebral hemiatrophy (Dyke-Davidoff-Masson Syndrome).

    PubMed

    Unal, Ozkan; Tombul, Temel; Cirak, Bayram; Anlar, Omer; Incesu, Lütfi; Kayan, Mustafa

    2004-01-01

    Although radiological findings of cerebral hemiatrophy (Dyke-Davidoff-Masson Syndrome) are well known, there is no systematic study about the gender and the affected side in this syndrome. Brain images in 26 patients (mean aged 11) with cerebral hemiatrophy were retrospectively reviewed. Nineteen patients (73.5%) were male and seven patients (26.5%) were female. Left hemisphere involvement was seen in 18 patients (69.2%) and right hemisphere involvement was seen in eight patients (30.8%). We conclude that male gender and left side involvement are frequent in cerebral hemiatrophy disease.

  16. Quantitative analogue modelling of the surface deformation associated with cone-sheet and dyke emplacement

    NASA Astrophysics Data System (ADS)

    Guldstrand, Frank; Bjugger, Fanny; Galland, Olivier; Burchardt, Steffi; Hallot, Erwan

    2014-05-01

    Inclined cone-sheets and sub-vertical dykes constitute the two principal types of magmatic sheet intrusions produced by volcanic systems. In active volcanic systems, the emplacement of sheet intrusions causes measurable surface deformation, which is analyzed through geodetic models. Geodetic model output is classically the shape of underlying intrusions causing the surface deformation, however, the results of these models are not testable as the subsurface intrusion is not accessible. Such test would only be doable with a physical system in which both (1) the surface deformation pattern and (2) the 3D shape of the underlying intrusion are known. In addition, established geodetic models only consider static magma intrusions, and do not account for emplacement and propagation processes. This would require combined good time- and space-resolution, which is not achievable with classical geodetic monitoring systems. We present a series of analogue models that may be a way of accurately linking surface deformation to the underlying intrusions and associated emplacement processes. We systematically varied depth of intrusion, the cohesive properties of the silica powder representing the country rock and the velocity of injected magma. The pressure of the intruding vegetable oil was measured through time, and the model surface topography was monitored. The low viscosity magma was simulated by molten vegetable oil, which solidified after intrusion; the solidified intrusion was then excavated and its shape was measured. By linking the development of the surface uplift in height, area, and volume with the pressure data from the onset of intrusion until the time of eruption, we identify characteristic laws of surface deformation. First results indicate that the pattern of uplift over time varies, depending on whether deformation is caused by a dyke- or a cone-sheet-shaped intrusion. The results from all experiments may enable us to distinguish the two intrusion types using

  17. Magma storage and evolution in the Henties Bay-Outjo dyke swarm, Namibia -feeder systems of the Etendeka lavas

    NASA Astrophysics Data System (ADS)

    Keiding, J. K.; Frei, O.; Renno, A.; Veksler, I. V.; Trumbull, R. B.

    2012-04-01

    At the roots of continental flood basalts in the Paraná-Etendeka province are mafic dyke swarms that cover areas of several hundred kilometers. Studies of these dykes have focused mainly on the age, paleomagnetic properties and geochemistry, but less on pressure (P) and temperature (T) conditions of emplacement. However, the P and T conditions under which dyke magmas are stored are crucial for models of magma plumbing systems in flood basalt provinces. The erupted lavas are typically far from primitive compositions and generally show evidence for strong crustal assimilation in addition to magma fractionation. Unknown is where this magma modification took place in the crust. This is the kind of information that dyke studies can provide. The Henties Bay Outjo dyke swarm (HOD) in NW Namibia is the subject of this study. This is inarguably the best exposed of major dyke swarms associated with South Atlantic rifting and breakup and its geochemical diversity is well documented but aspects relating to the magma dynamics in the dyke swarm have not been studied before. Our approach is to use geochemical data from selected dykes to assess the differentiation and assimilation history of the magmas, and combine that with petrologic constraints on the temperature-pressure conditions of crystallization derived from mineral-melt equilibria. We have determined P-T estimates from olivine-melt and clinopyroxene-melt equilibria using analysis of phenocrysts by electron microprobe and applying the thermodynamic relations from Putirka (2008), who considered the standard error to be 1.7 kbar and 30°C. The calculations reflect only mineral-melt (proxied by whole-rock) compositions that are consistent with equilibrium. Crystallization temperatures range from 1040°C to 1350°C with a mean (n=58) of 1170 °C. These T-variations are not random, the high-temperature results come from a specific region of dyke emplacement but the reason for this is not yet clear. Olivine-melt temperatures

  18. New U-Pb ages from dykes cross-cutting the Demirci metamorphics, NW Turkey: Implications for multiple orogenic events

    NASA Astrophysics Data System (ADS)

    Sen, Fatih; Koral, Hayrettin; Peytcheva, Irena

    2016-04-01

    A high-grade metamorphic sequence in the Sünnice Mountains, Bolu, NW Turkey, is represented by migmatitic quartzo-feldspathic gneisses in amphibolite facies called the Demirci metamorphics/paragneisses, and a sequence of low-grade meta-volcanics containing meta-andesites with minor meta-rhyolites and meta-sedimentary rocks called the Yellice meta-volcanics. They are intruded by the Dirgine granite with an age of Upper Ediacaran (576-565 Ma) and are considered a part of the İstanbul-Zonguldak Tectonic Unit. The Demirci paragneisses are also intruded by a number of dykes in various directions, traditionally considered without radiometric dating to have been emplaced in a single magmatic phase in the Eocene related to post-collision regime of the Anatolide-Tauride platform. Mafic-intermediate-felsic dykes cross-cutting the Demirci paragneisses have been investigated in maps of 1/1000 scale, and their U-Pb zircon age, major-trace element and kinematic data have been obtained. The mafics dykes cross-cutting the Yellice meta-volcanics, equivalents of those in the Demirci paragneisses, occur in N400-500E orientations and have calc-alkaline basalt compositions with a subduction signature. The intermediate dykes occur in N650W, N800W orientations and have calc-alkaline basaltic andesite to andesitic compositions with a subduction signature. Some felsics occur in N150W and N800E orientations and have calc-alkaline dacitic compositions with a collisional tectonic setting. Other calc-alkaline granitic dykes occur in N750E orientation and calc-alkaline granitic compositions with a subduction signature. U-Pb LA-ICP-MS dating of zircons yield ages from 485.7±3.6 Ma (i.e. Cambro-Ordovician) for N800E trending dacite dykes; 443.0±5.4 Ma (i.e. Ordovician-Silurian) for N150W trending dacite dykes; 301.0±1.6 Ma (i.e. Upper Pennsylvanian-Carboniferous) for N650W trending basaltic andesite dykes; 268.2±2.4 Ma (i.e. Guadalupian-Permian) for N40-500E trending basalt dykes; 262.9±3

  19. 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, Zhiming; 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.

  20. 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.

  1. Interview with a quality leader: Karen H. Timmons on education and consultation with Joint Commission Resources. Interview by Susan V. White.

    PubMed

    Timmons, Karen H

    2009-01-01

    In this interview, Karen Timmons of the Joint Commission Resources Inc. (JCR) responds to questions about the role JCR plays in promoting patient safety and quality in the international community. Ms. Timmons describes the types of services provided by JCR including strategies, approaches, and challenges. She concludes with recent work examples and some personal perspectives.

  2. Palaeointensity and palaeodirection determinations of Paleoproterozoic dykes in the Kaapvaal Craton (South Africa)

    NASA Astrophysics Data System (ADS)

    Shcherbakova, V. V.; Lubnina, N. V.; Shcherbakov, V. P.; Zhidkov, G. V.

    2012-04-01

    A combined palaeodirectional and palaeointensity study of a representative collection from the Bushveld Igneous Complex from 27 dolerite dykes from the 2.9, 2.7, and 1.8 Ga age swarms radiating SE, E and NE, respectively [Olsson et al., 2010] was carried out. Conventional progressive thermal or AF demagnetization was applied to all specimens. The palaeomagnetic directions have been calculated after thermal demagnetization. The ChRMs were isolated over the temperature interval 440-590 C and their intensities amount to 95% of total NRMs. Paleopole calculate from the primary high-temperature component, separated in the 2.9 Ga SE-dykes, is close to the paleopoles, obtained by Wingate (1998) and Strik et al. (2007) for 2.78 Ga volcanics. The paleopole calculated for the 2.7 Ga age E-trending dykes of the eastern region does not correspond to any of the previously obtained Archean-Paleoproterozoic paleopoles for the Kaapvaal Craton. The paleopole calculated for some NE-trending dykes of the Black Ridge swarm in the NE region is close to the 1.87 Ga pole of the Kaapvaal Craton obtained by Hanson et al. (2004). Palaeointensity determinations were carried out on rocks from ten dykes of different ages using Thellier-Coe method with the "check-points" procedure on specimens of 1 cm in edge length cut from either drilled cores or hand samples. Rock magnetic measurements were made on sister specimens. Curie temperatures and the thermal stability of magnetic minerals were estimated from thermomagnetic heating-cooling cycles to incrementally higher temperatures Ti with a Curie balance in an external magnetic field H = 0.45 T. To assess the magnetic hardness and mineralogy of samples, measurements of magnetic susceptibility and hysteresis loop parameters were performed. The domain structure (DS) was estimated also from the thermomagnetic criterion by evaluating the tails of pTRMs. Wilson's method of palaeointensity determination based on comparison of thermodemagnetization curves

  3. Ordovician and Triassic mafic dykes in the Wudang terrane: Evidence for opening and closure of the South Qinling ocean basin, central China

    NASA Astrophysics Data System (ADS)

    Nie, Hu; Wan, Xin; Zhang, He; He, Jian-Feng; Hou, Zhen-Hui; Siebel, Wolfgang; Chen, Fukun

    2016-12-01

    We report zircon ages and geochemical composition for mafic dykes that intruded Neoproterozoic volcanic-sedimentary sequences in the southern part of Wudang area, South Qinling. The results indicate that the dykes were emplaced during the Early Paleozoic (c. 460 Ma) and Early Mesozoic (c. 220 Ma). The dykes share similar major element composition, but have distinctive trace element pattern and Sr-Nd-Pb isotope distribution. Early Paleozoic mafic dykes are characterized by enrichment in LREEs, LILEs and HFSEs and EM II-type isotopic features. These geochemical features suggest derivation from an OIB-type mantle source that had undergone metasomatism during earlier subduction events. The Early Mesozoic mafic dykes can be subdivided into two distinct geochemical groups. Dykes of Group 1 are depleted in LREEs, LILEs and HFSEs and show depleted isotope compositions, indicating an origin by partial melting of asthenospheric mantle material. Dykes of Group 2 have high Rb-, Ba-, and K-contents and EM I-type isotopic features, suggesting input of lower crustal material to the magma source during Mesozoic subduction. We propose that the Early Paleozoic dykes are related to the opening of an oceanic basin separating South Qinling from the Yangtze Block, while the Early Mesozoic dykes were derived from partial melting of up-welling asthenosphere during the final amalgamation of these two blocks in the Early Mesozoic. A slab break-off model could explain not only the petrogenesis of the Mesozoic mafic dykes, but also the distinct geological features between the Dabie-Sulu and South Qinling orogens. We propose that slab break-off occurred at great depth in the Dabie-Sulu orogen and hence rare magmatism occurred. Whereas in South Qinling the break-off occurred at a shallow depth, the asthenospheric mantle material could rise further up into the overlying mantle where it experienced decompression and melting. As a consequence, crustal sections were heated up to produce extensive

  4. Piloting community-based medical care for survivors of sexual assault in conflict-affected Karen State of eastern Burma

    PubMed Central

    2013-01-01

    Background Given the challenges to ensuring facility-based care in conflict settings, the Women’s Refugee Commission and partners have been pursuing a community-based approach to providing medical care to survivors of sexual assault in Karen State, eastern Burma. This new model translates the 2004 World Health Organization’s Clinical Management of Rape Survivors facility-based protocol to the community level through empowering community health workers to provide post-rape care. The aim of this innovative study is to examine the safety and feasibility of community-based medical care for survivors of sexual assault to contribute to building an evidence base on alternative models of care in humanitarian settings. Methods A process evaluation was implemented from July-October 2011 to gather qualitative feedback from trained community health workers, traditional birth attendants, and community members. Two focus group discussions were conducted among the highest cadre health care workers from the pilot and non-pilot sites. In Karen State, eight focus group discussions were convened among traditional birth attendants and 10 among women and men of reproductive age. Results Qualitative feedback contributed to an understanding of the model’s feasibility. Pilot site community health workers showed interest in providing community-based care for survivors of sexual assault. Traditional birth attendants attested to the importance of making this care available. Community health workers were deeply aware of the need to maintain confidentiality and offer compassionate care. They did not raise safety as an excess concern in the provision of treatment. Conclusions Data speak to the promising “feasibility” of community-based post-rape care. More time, awareness-raising, and a larger catchment population are necessary to answer the safety perspective. The pilot is an attempt to translate facility-based protocol to the community level to offer solutions for settings where

  5. Creep of mafic dykes infiltrated by melt in the lower continental crust (Seiland Igneous Province, Norway)

    NASA Astrophysics Data System (ADS)

    Degli Alessandrini, G.; Menegon, L.; Malaspina, N.; Dijkstra, A. H.; Anderson, M. W.

    2017-03-01

    A dry mafic dyke from a continental lower-crustal shear zone in the Seiland Igneous Province (northern Norway) experienced syn-kinematic melt-rock interaction. Viscous shearing occurred at T ≈ 800 °C, P ≈ 0.75-0.95 GPa and was coeval with infiltration of felsic melt from adjacent migmatitic metapelites. The dyke has a mylonitic microstructure where porphyroclasts of orthopyroxene, clinopyroxene and plagioclase are wrapped by a fine-grained (4-7 μm) polyphase mixture of clinopyroxene + orthopyroxene + plagioclase + quartz + ilmenite ± K-feldspar ± apatite. Microstructural observations and electron backscatter diffraction analysis indicate that the porphyroclasts deformed by a combination of dislocation glide and fracturing, with only a limited record of dislocation creep, recovery and dynamic recrystallization. We identified diffusion creep as the dominant deformation mechanism in the mixture based on the small grain size, phase mixing and weak crystallographic preferred orientation of all phases (interpreted as the result of oriented grain growth during viscous flow). The polyphase mixture did not form by dynamic recrystallization or by mechanical fragmentation of the porphyroclasts, but rather by melt-rock interaction. Thermodynamic models indicate that the syn-kinematic mineral assemblage results from the chemical interaction between a pristine mafic dyke and ca. 10 vol.% of felsic melt infiltrating from the adjacent partially molten metapelites. Extrapolation of laboratory-derived flow laws to natural conditions indicates that the formation of interconnected layers of fine-grained reaction products deforming by diffusion creep induces a dramatic weakening in the mafic granulites, with strain rates increasing up to 2-3 orders of magnitude. The reaction weakening effect is more efficient than the weakening associated with melt-assisted diffusion creep in the presence of up to 10 vol.% of infiltrated melt without formation of fine-grained reaction products

  6. Parental magma of the Skaergaard intrusion: constraints from melt inclusions in primitive troctolite blocks and FG-1 dykes

    NASA Astrophysics Data System (ADS)

    Jakobsen, Jakob K.; Tegner, Christian; Brooks, C. Kent; Kent, Adam J. R.; Lesher, Charles E.; Nielsen, Troels F. D.; Wiedenbeck, Michael

    2010-01-01

    Troctolite blocks with compositions akin to the Hidden Zone are exposed in a tholeiitic dyke cutting across the Skaergaard intrusion, East Greenland. Plagioclase in these blocks contains finely crystallised melt inclusions that we have homogenised to constrain the parental magma to 47.4-49.0 wt.% SiO2, 13.4-14.9 wt.% Al2O3 and 10.7-14.1 wt.% FeOT. These compositions are lower in FeOT and higher in SiO2 than previous estimates and have distinct La/SmN and Dy/YbN ratios that link them to the lowermost volcanic succession (Milne Land Formation) of the regional East Greenland flood basalt province. New major- and trace element compositions for the FG-1 dyke swarm, previously taken to represent Skaergaard magmas, overlap with the entire range of the regional flood basalt succession and do not form a coherent suite of Skaergaard like melts. These dykes are therefore re-interpreted as feeder dykes throughout the main phase of flood basalt volcanism.

  7. Dyke propagation and tensile fracturing at high temperature and pressure, insights from experimental rock mechanics.

    NASA Astrophysics Data System (ADS)

    Bakker, Richard; Benson, Philip; Vinciguerra, Sergio

    2014-05-01

    It is well known that magma ascends trough the crust by the process of dyking. To enable dyke emplacement, basement rocks typically fail in a mode 1 fracture, which acts as conduits for magma transport. An overpressure of the ascending magma will further open/widen the fracture and permit the fracture to propagate. In order to further understand the emplacement and arrest of dykes in the subsurface, analogue and numerical studies have been conducted. However, a number of assumptions regarding rock mechanical behaviour frequently has to be made as such data are very hard to directly measure at the pressure/temperature conditions of interest: high temperatures at relatively shallow depths. Such data are key to simulating the magma intrusion dynamics through the lithologies that underlie the volcanic edifice. Here we present a new laboratory setup, which allows us to investigate the tensile fracturing properties under both temperature and confining pressure, and the emplacement of molten material within the newly formed fracture. We have modified a traditional tri-axial test assembly setup to be able to use a Paterson type High Pressure, High Temperature deformation apparatus. Sample setup consists of cylindrical rock samples with a 22 mm diameter and a 8 mm bore at their centre, filled with a material chosen as such that it's in a liquid state at the experimental temperature and solid at room temperature to enable post-experiment analysis. The top and lower parts of the rock sample are fitted with plugs, sealing in the melt. The assembly is then placed between ceramic pistons to ensure there are no thermal gradients across the sample. The assembly is jacketed to ensure the confining medium (Ar) cannot enter the assembly. A piston is driven into the sample such that the inner conduit materials pressure is slowly increased. At some point a sufficient pressure difference between the inner and outer surfaces causes the sample to deform and fail in the tensile regime

  8. 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.

  9. Composition of the Tarim mantle plume: Constraints from clinopyroxene antecrysts in the early Permian Xiaohaizi dykes, NW China

    NASA Astrophysics Data System (ADS)

    Wei, Xun; Xu, Yi-Gang; Luo, Zhen-Yu; Zhao, Jian-Xin; Feng, Yue-Xing

    2015-08-01

    Numerous alkaline basaltic dykes crosscut the Early Permian Xiaohaizi wehrlite in drill-cores and syenite intrusion in the Tarim large igneous province, NW China. One basaltic dyke contains abundant clinopyroxene macrocrysts with strong resorption textures. Such a textural disequilibrium is consistent with their contrasting chemistry between the macrocrysts (Mg# = 80-89) and the host dyke (Mg# = 39, corresponding to Mg# = 73 of clinopyroxene in equilibrium with the dyke), indicating that they are not phenocrysts. The clinopyroxene macrocrysts are characterized by low TiO2 (0.26-1.09 wt.%), Al2O3 (1.15-3.10 wt.%) and Na2O (0.16-0.37 wt.%), unlike those in mantle peridotites but resembling those in layered mafic intrusions in the same area. The clinopyroxene macrocrysts and the clinopyroxenes from the Xiaohaizi cumulate wehrlites define a coherent compositional trend and have identical trace element patterns, pointing to a comagmatic origin for these crystals. Accordingly, the macrocrysts cannot be xenocrysts foreign to the magmatic system. Rather they are antecrysts that crystallized from progenitor magmas and have been reincorporated into the host dyke before intrusion. The 87Sr/86Sri (0.7035-0.7037) and εNdi (4.5-4.8) of the clinopyroxene macrocrysts with high Mg# (80-89) are apparently lower and higher than their respective ratios of the clinopyroxenes in the wehrlites (Mg# = 75-84, 87Sr/86Sri = 0.7038-0.7041, εNdi = 1.0-1.9). This difference in isotopes can be accounted for by assimilation and fractional crystallization (AFC) process operated during the formation of the Xiaohaizi intrusion. In this sense, the clinopyroxene macrocrysts record the composition of the uncontaminated Tarim plume-derived melts.

  10. Shoshonitic and ultrapotassic post-collisional dykes from northern Karakorum (Sinkiang, China)

    NASA Astrophysics Data System (ADS)

    Pognante, Ugo

    1991-01-01

    High-K calc-alkaline, shoshonitic and ultrapotassic post-collisional dykes of Neogene age have been found in the remote and little known region of northern Karakorum located around the Shaksgam valley, north of the K2-Gasherbrum range (China). The dykes derive from more or less comparable basic magma(s) and display rather unusual petrographic and geochemical characters with respect to the other K-rich rocks. The geochemical data are consistent with derivation of the basic magma(s) from small degrees of partial melting of garnet-lherzolites previously enriched in incompatible elements of crustal origin possibly during the subduction of the Indian plate beneath Karakorum. The spectrum of compositions reflects fractional crystallization governed by an early removal of clinopyroxene, phlogopite, plagioclase, garnet±amphibole followed by the precipitation of abundant alkali feldspar, amphibole±apatite±quartz. Additionally, assimilation of crustal rocks during magma ascent contributed to the unusual compositional characteristics and is suggested by the abundance of corroded quartz ( ± plagioclase) xenocrysts and by the occasional presence of granitic xenoliths. An apparent connection exists between magmatism and tectonism in the complex Karakorum Fault Zone (KFZ). It is suggested that, during the Neogene, the strike-slip KFZ and some adjacent post-metamorphic faults transiently behaved as extensional fault systems down to deep levels, triggering ascent and emplacement of the K-rich magma. The subsequent (re)activation of a compressive and transcurrent regime determined the rapid and recent uplift of the more primitive lamprophyres occurring in the plutonites and metamorphites of the upper Baltoro Glacier and K2-Gasherbrum range, relative to the more fractionated and contaminated lamprophyres injecting the shallower rocks of the Shaksgam valley area.

  11. Post-collisional magmatism associated with Variscan orogeny in the Danubian Domain (Romanian Southern Carpathians): the Motru Dyke Swarm

    NASA Astrophysics Data System (ADS)

    Stremtan, C. C.; Campeanu, M.; Balica, C.; Ryan, J. G.; Savov, I. P.; Balintoni, I.

    2012-12-01

    The metamorphic basement of the Danubian nappe system in the Romanian Southern Carpathians is comprised of Neoproterozoic high-grade metamorphics and granitoid intrusions, underlying low-grade Ordovician to early Carboniferous formations. This entire sequence is intruded by late Variscan age (Carboniferous to early Permian) post-collisional granitoid plutons. The Motru Dyke Swarm (MDS), a geographically-extensive system of intermediate to felsic dykes crosscuts the whole Danubian basement. Zircon U/Pb results on some MDS dikes indicate a largely inherited zircon population with an age distribution pointing to Pan-African origins and a peri-Amazonian provenance for MDS crustal sources. However, in the field the MDS dykes cross-cut late Variscan post-collisional plutons, supporting the assertion that these dykes are much younger, with Upper Paleozoic, most likely Carboniferous (Variscan) ages. This study is aimed at providing a better understanding of the petrogenesis, emplacement age, and evolution of the MDS using zircon U/Pb dating, geochemical, isotope, and petrographic data. The dykes record heterogeneous petrographic and geochemical (major and trace elements, as well as radiogenic isotope) signatures. MDS dykes are mainly basaltic-andesite, andesite, trachyandesite, and dacite in composition and petrography with porphyritic basaltic andesites being the most common. The absence of olivine and the presence of brownish amphibole, biotite- and quartz-mantled zircons, as well as mm- to cm-size enclaves of meta-sediments are the most distinctive petrologic features of the MDS. Published[1] major elements compositions define a complete differentiation series, ranging from basaltic andesites to rhyolites (50-72 wt% SiO2) with medium-K to shoshonitic calc-alkaline characteristics. The dykes are dominantly metaluminous (average ASI of 0.90). Considerable heterogeneity is preserved in their trace element compositions: ΣREE ranges from 41.18 to 378, Eu/Eu* from 0.79 to 1

  12. 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

  13. Upper and lower crust recycling in the source of CAMP basaltic dykes from southeastern North America

    NASA Astrophysics Data System (ADS)

    Callegaro, Sara; Marzoli, Andrea; Bertrand, Hervé; Chiaradia, Massimo; Reisberg, Laurie; Meyzen, Christine; Bellieni, Giuliano; Weems, Robert E.; Merle, Renaud

    2013-08-01

    The densest dykes swarm of the Central Atlantic magmatic province (CAMP) occur in southeastern North America (SENA) and were intruded between 202 and 195 Ma during Pangea break-up. New combined geochemical data (major and trace elements, Sr-Nd-Pb-Os isotopes) constrain the mantle source of these magmatic bodies and their evolution path. While Sr-Nd isotopic compositions for SENA rocks (87Sr/86Sr200Ma 0.70438-0.70880 and 143Nd/144Nd200Ma 0.51251-0.51204) fall within the low-Ti CAMP field, Pb-Pb isotopes (206Pb/204Pb200Ma 17.46-18.85, 207Pb/204Pb200Ma 15.54-15.65, 208Pb/204Pb200Ma 37.47-38.76) are peculiar to this area of the CAMP and cover a considerable span of compositions, especially in 206Pb/204Pb200Ma. Given the generally unradiogenic Os isotopic compositions (187Os/188Os200Ma 0.127-0.144) observed and the lack of correlation between these and other geochemical markers, crustal contamination during the evolution of SENA dykes must have been limited (less than 10%). Thus the isotopic variation is interpreted to reside primarily within the mantle source. These observations, coupled with typical continental signatures in trace elements (positive anomaly in Pb and negative anomalies in Ti and Nb), require another means of conveying a continental flavor to these magmas, which is here hypothesized to be the shallow recycling within the upper mantle of subducted lower and upper crustal materials. Pseudo-ternary mixing models show that a maximum of 10% recycled crust is enough to explain their trace element patterns as well as their isotopic heterogeneity. Looking at the larger picture of the origin of the CAMP, the thermal contribution of a mantle plume cannot be ruled out due to the relatively high mantle potential temperatures (1430-1480 °C) calculated for high-Fo SENA olivines. Nevertheless, our results suggest that the chemical involvement of a mantle plume is negligible (less than 5%) if either a C- or an EM-flavored plume is considered. Rather, the possibility

  14. 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

  15. Link between extension, dyking and subsidence as the reconstruction tool of intraplate rifting mechanism (backstripping data, modelling and geochronology)

    NASA Astrophysics Data System (ADS)

    Polyansky, Oleg P.; Reverdatto, Vladimir V.; Babichev, Alexey V.

    2014-05-01

    Correlation between subsidence and extension-related magmatism is key in determining mechanism of intracratonic sedimentary basins formation. The total volume of basic sheet intrusions and volcanics within sedimentary rock mass characterizes indirectly the degree of depletion and thinning of the rifted mantle lithosphere. At present the documented features of real-world intracontinental basins show a wide range of parameters characterizing the duration and rate of subsidence, degree of extension/thinning of the lithosphere, age and extent of dyking. For creation of general model of continental rifting it is important to reconstruct an evolution of basins finished at the continental stage, not entered an oceanic spreading phase. One of examples of such structure is the Vilyui sedimentary basin in the eastern Siberian Platform which includes the massive emplacements (10**5 km3) of extrusive and intrusive rocks of the Vilyui large igneous province. We combine backstripping reconstructions of sedimentation and thermal regime during the subsidence with a numerical modelling based on the deformable solid mechanics. It is the first time that the evolution of sedimentation and subsidence which is nonuniform over the basin area has been analyzed for the Vilyui basin. The rift origin of the basin is proved. We estimate the spatial distribution of the parameters of crustal and mantle-lithosphere extension as well as expansion due to dike intrusions. According to the reconstructions, the type of subsidence curves for the sedimentary rocks of the basin depends on the tectonic regime of sedimentation in individual subbasins. The backstripping analysis revealed two stages of extension (sediments 4-5 km thick) and a foreland stage (sediments >2 km thick). With the two-layered lithosphere model, we concluded that the subcrustal layer underwent predominant extension (by a factor of 1.2-2.0 vs. 1.1-1.4 in the crust). In each section, dyke-related extension due to basic intrusion is

  16. Earthquake focal mechanisms associated with dyke propagation and caldera collapse at the Bárðarbunga volcano, Iceland

    NASA Astrophysics Data System (ADS)

    Hensch, Martin; Cesca, Simone; Heimann, Sebastian; Rivalta, Eleonora; Hjörleifsdóttir, Vala; Jónsdóttir, Kristín; Vogfjörð, Kristín; Dahm, Torsten

    2015-04-01

    The dyke intrusion at the Bárðarbunga volcanic system which started on 16 August 2014, as well as the subsidence of its caldera were accompanied by an intense seismic swarm along the propagation path of the dyke and around the caldera ring fault. In this study we analyse focal mechanisms of both clusters, along the dyke and around the caldera rim, to reveal driving forces of the seismic and volcanic activity. Full moment tensors are determined for events larger than Mw 4.5 to obtain more complex mechanisms, especially for earthquakes associated with the caldera collapse. Within the first two weeks between the onset of the seismic swarm and the opening of the first fissure eruption, an approximately 45 km long dyke migrated northeastwards from the caldera to the eruption site a few kilometers outside the glacier margin of the Vatnajökull ice cap. The dyke propagated with irregular velocities, alternating phases of arrest and spurts were accompanied by thousands of earthquakes of magnitudes up to Mw 4.5. The focal mechanisms range from strike-slip to normal faulting around the dyke, with a stable tension axis perpendicular to the dyke. Seismicity along the intrusion was driven by tensional stresses accumulated in the shallow crust and pressure induced by the magma intrusion itself. This assumption is supported by the significant drop of activity following the onset of the fissure eruption. In contrast, the seismic activity around the caldera rim remains at high levels since the onset of the crisis while the underlying magma reservoir continues deflating. The caldera floor of Bárðarbunga has subsided by around 60 m since August. The strongest earthquakes on the ring fault reached up to Mw 5.7 and several dozens of events were larger than Mw 5. A moment tensor inversion of these events revealed consistent steep normal faulting with a significant compensated linear vector dipole component (CLVD). This mechanism can be explained by two different models: (1) A

  17. 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.

  18. Gridino melange zone of the Belomorian eclogite province: Succession of tectonic events and structural position of mafic dyke swarms

    NASA Astrophysics Data System (ADS)

    Babarina, I. I.; Sibelev, O. S.; Stepanova, A. V.

    2014-07-01

    Based on relationships between Paleoproterozoic mafic dykes, lithotectonic complexes, and tectonic structures of the Gridino Zone in the Belomorian eclogite province of the Fennoscandian Shield, deformations have been divided into groups differing in age and the succession of tectonic events has been reconstructed. The formation of Neoarchean eclogite-bearing melange was related to disintegration of large eclogite sheets in the course of near-horizontal ductile flow accompanied by syntectonic granitoid magmatism, multiple migmatization, and granulite-to amphibolite-facies metamorphism. The exotic blocks, including eclogites, were incorporated into TTG gneisses as sheets and lenses up to a few hundreds of meters in thickness and oriented conformably with gneissic banding. As a result of ductile flow, the lithotectonic complexes were transported at the level of discrete brittle-ductile deformations expressed as strike-slip faults and associated folds. Under conditions of a relatively rigid medium, individual structural elements underwent rotation approximately through 90° in plan view. Under the extension regime in the Early Paleoproterozoic, several swarms of mafic dykes were injected into the already cold framework rocks, as is evident from dyke morphology. The dykes crosscut all predated structures, included turned blocks, and are therefore important reference points for subdivision of Neoarchean and Paleoproterozoic processes. The Svecofennian postdyke tectonic activity was accompanied by local shearing and boudinage of metabasic rocks, development of quartz and pegmatite veins along tension cracks, disharmonic folding, and discrete retrograde metamorphism up to amphibolite-facies conditions. The postdyke deformations did not exert a substantial effect on the previously formed regional structure.

  19. 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.

  20. 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.

  1. Evidence for dyke intrusion earthquake mechanisms near long valley caldera, California

    USGS Publications Warehouse

    Julian, B.R.

    1983-01-01

    A re-analysis of the magnitude 6 earthquakes that occurred near Long Valley caldera in eastern California on 25 and 27 May 1980, suggests that at least two of them, including the largest, were probably caused by fluid injection along nearly vertical surfaces and not by slip on faults. Several investigators 1,2 have reported difficulty in explaining both the long-period surface-wave amplitudes and phases and the locally recorded short-period body-wave first motions from these events, using conventional double-couple (shear fault) source models. They attributed this difficulty to: (1) complex sources, not representable by single-fault models; (2) artefacts of the analysis methods used; or (3) effects of wave propagation through hypothetical structures beneath the caldera. We show here that the data agree well with the predictions for a compensated linear-vector dipole (CLVD) equivalent-force system3 with its principal extensional axis horizontal and trending N 55-65?? E. Such a mechanism is what would be expected for fluid injection into dykes striking N 25-35?? W, which is the approximate strike of numerous normal faults in the area. ?? 1983 Nature Publishing Group.

  2. Segmented Dyke Growth and Associated Seismicity at Bárðarbunga Volcanic System (Iceland) is Driven by Non-Linear Magma Pressure Diffusion

    NASA Astrophysics Data System (ADS)

    Langenbruch, C.

    2015-12-01

    In August 2014 segmented lateral dyke growth has been observed in a rifting event at Bardarbunga volcanic system, Iceland. The temporal evolution of the magma source and the physical nature of magma flow process during dyke propagation and arrest are unclear. The epidemic-type aftershock sequence model has been used to detect fluid signals in seismicity data. We use the earthquake catalog recorded during the rifting event to reconstruct the magma flow signal at the feeding source of the dyke. We find that the segmentation of dyke growth is caused by a pulsating nature of the magma flow source. We identify two main magma flow pulses, which initiate and propagate the two main segments of the dyke. During phases of dyke arrest magma flow pulses are low and cannot further propagate the dyke. We use the reconstructed magma flow signal to set up a numerical model of non-linear magma pressure diffusion. By using the magma pressure changes resulting from magma flow, we simulate the earthquake catalog caused by the reduction of the effective principal stress. We observe an excellent agreement between the spatio-temporal characteristics of the simulated earthquake catalog and recorded seismicity. Our results suggest that the process of magma pressure relaxation can be described as a non-linear diffusion process. Because the opening of the dyke creates significant new fracture volume, the permeability of the rock is strongly increasing and the diffusion process becomes highly non-linear. Our analysis is based on lessons learned from analysis of seismicity observed during hydraulic fracturing of hydrocarbon reservoirs. Despite large differences in scale, the underlying physical processes are comparable. Finally, we analyze the decay of seismic activity after start of the effusive fissure eruption near the end of the dyke. The magma flow strongly decreases and seismic activity decays according to Omori's law, which describes the decay of aftershock activity after tectonic

  3. Characterization of the effect of dyke swarms on groundwater flow in a sedimentary coastal aquifer by combined geophysical and hydrogeological modelling

    NASA Astrophysics Data System (ADS)

    Burns, C.; Comte, J.; Gaffney, L.; Ofterdinger, U.; Young, M.

    2010-12-01

    In many parts of the North Atlantic region, the Permo-Triassic New Red Sandstone constitutes an important groundwater resource for drinking, agricultural and industrial water supply, thanks to relatively high transmissivity and storage properties. Such old sedimentary basins are often intruded by Paleogene volcanic dykes generally following the extensive deep fractures associated with the Mesozoic opening of the Atlantic Ocean. From local to regional scale, the effect of dyke swarms on the groundwater flow in these aquifers (i.e. as barriers, drains, or anisotropic bands) is poorly understood due to both the discrete nature of their occurrence and in many cases the existence of overlying deposits preventing their direct observation. To the Triassic Sherwood sandstone aquifer near Belfast, Northern Ireland, a combined modeling approach has been applied on a selected coastal site to evaluate the effect of dykes on groundwater flow. Geophysics was used to detect and map the dykes and natural seawater intrusion. First, information on the location, orientation and dipping of the dykes was provided by surface geomagnetic investigations and modeling. Second, electrical resistivity tomography (ERT) was applied to image both the dykes and the groundwater salinity. Inverse modeling of resistivity data is constrained using the dyke geometries from geomagnetic modeling. Thirdly, a variable-density groundwater flow model is applied, using established hydrogeological data, to simulate both the aquifer hydrodynamics and the saltwater distribution. Finally, several scenarios of permeability properties of the dykes are tested and the results compared to the seawater distribution provided by the geo-electrical models. Such a comparison allows discrimination of unrealistic scenarios, as well as both validating the groundwater numerical model and improving its calibration. Thus, it is shown that (1) at the local scale, the dykes act as low permeability zones, i.e. relative barriers

  4. The Deccan tholeiite lavas and dykes of Ghatkopar-Powai area, Mumbai, Panvel flexure zone: Geochemistry, stratigraphic status, and tectonic significance

    NASA Astrophysics Data System (ADS)

    Sheth, Hetu C.; Zellmer, Georg F.; Demonterova, Elena I.; Ivanov, Alexei V.; Kumar, Rohit; Patel, Rakesh Kumar

    2014-04-01

    Mumbai City, situated on the western Indian coast, is well known for exposures of late-stage Deccan pillow basalts and spilites, pyroclastic rocks, rhyolite lavas, and trachyte intrusions. These rock units, and a little-studied sequence of tholeiitic flows and dykes in the eastern part of Mumbai City, constitute the west-dipping limb of a regional tectonic structure called the Panvel flexure. Here we present field, petrographic, major and trace element and Sr-Nd isotopic data on these tholeiitic flows and dykes, best exposed in the Ghatkopar-Powai area. The flows closely resemble the Mahabaleshwar Formation of the thick Western Ghats sequence to the east, in Sr-Nd isotopic ratios and multielement patterns, but have other geochemical characteristics (e.g., incompatible trace element ratios) unlike the Mahabaleshwar or any other Formation. The flows may have originated from a nearby eruptive center, possibly offshore of Mumbai. Two dykes resemble the Ambenali Formation of the Western Ghats in all geochemical characteristics, though they may not represent feeders of the Ambenali Formation lavas. Most dykes are distinct from any of the Western Ghats stratigraphic units. Some show partial (e.g., Sr-Nd isotopic) similarities to the Mahabaleshwar Formation, and these include several dykes with unusual, concave-downward REE patterns suggesting residual amphibole and thus a lithospheric source. The flows and dykes are inferred to have undergone little or no contamination, by lower continental crust. Most dykes are almost vertical, suggesting emplacement after the formation of the Panvel flexure, and indicate considerable east-west lithospheric extension during this late but magmatically vigorous stage of Deccan volcanism.

  5. Prevalence of parasitism among students of the Karen hill-tribe in Mae Chame district, Chiang Mai province, Thailand.

    PubMed

    Saksirisampant, Wilai; Prownebon, Jarruratt; Kanmarnee, Penjit; Thaisom, Sunida; Yenthakam, Sutin; Nuchprayoon, Surang

    2004-09-01

    Infection caused by intestinal parasites is still a common health problem in a poor-hygiene population especially for children in developing countries. A cross-sectional study was conducted among 781 Karen students (age: 3 to 19, males: 325, females: 456) to determine the current status of intestinal parasitic infections in a mountainous area in the North of Thailand. The study was drawn from three schools in the Doi Inthanon region, in Mae Chame district of Chiang Mai province, from December 2002 to June 2003. The techniques used for the diagnosis were: stool concentration by using the 'formalin-ether' technique and perianal region examination by using the 'Scotch-tape' technique. The average rate of intestinal parasites for the group tested using the stool concentration technique was 42.06% (male: 46.87%, females: 38.82%); and 22.66% (males: 28.92%, females: 18.20%) when using the Scotch-tape technique.Among helminth-infected individuals, enterobiasis was found at the highest prevalence (15.49%). Other common infections were ascariasis (9.78%), trichuriasis (5.90%) and hookworm infection (2.20%). Strongyloildiasis was found only in 0.92%. For protozoa infection, the major cause is the non-pathogenic species "Entamoeba coli" (27.68%). The other non-pathogenic protozoa (Endolimax nana, Chilomastix meslini and Iodamoeba butschlii) had a low prevalence from ranged 0.18%-4.79%. The prevalence of pathogenic Giardia lamblia infection was 2.21%. Entamoeba histolytica infection was found in only one case. Based on the two techniques used, the results from the Scotch-tape provided a higher sensitivity for the detection of Taenia spp. and Enterobius vermicularis eggs. Drug treatment was given to all the infected students. School-based health education should be implemented in order to prevent and control the infections.

  6. Magnetic studies and U Pb geochronology of the Uruguayan dyke swarm, Rio de la Plata craton, Uruguay: paleomagnetic and economic implications

    NASA Astrophysics Data System (ADS)

    Halls, Henry C.; Campal, Nestor; Davis, Don W.; Bossi, Jorge

    2001-09-01

    A U-Pb age on baddeleyite of 1790±5 Ma has been obtained from a single dyke of the Uruguayan tholeiitic dyke swarm from the Rio de la Plata craton. Palaeomagnetic results from this and 10 other dykes yield two components, one (A) has the following paleomagnetic parameters: declination=12°, inclination=-16°, α95=7°, latitude of paleopole=61°, longitude=-31°, dp=4°, dm=7°, paleolatitude=-8°, whereas another (B), about 20° steeper, has a direction closer to the present Earth's field direction in Uruguay. Neither magnetisation is considered primary, although the A component may represent a composite between B and a primary component. A field test for the primary nature of the remanences was inconclusive, and no primary pole positions of similar age from other South American cratons are available for comparison. The magnetic results demonstrate that darker-coloured andesite dykes that are sought for facing and monument stone (as 'black granite') can be easily differentiated from more andesi-basaltic, lighter coloured, less valuable dykes of the same swarm, using aeromagnetic data. The results suggest that a high resolution airborne magnetic survey could constitute an important exploration tool for the Uruguayan 'black granite' industry.

  7. Anisotropy of magnetic susceptibility in welded tuffs: application to a welded-tuff dyke in the tertiary Trans-Pecos Texas volcanic province, USA

    NASA Astrophysics Data System (ADS)

    Wolff, John A.; Ellwood, Brooks B.; Sachs, Scott D.

    1989-06-01

    Consideration of published anisotropy of magnetic susceptibility (AMS) studies on welded ignimbrites suggests that AMS fabrics are controlled by groundmass microlites distributed within the existing tuff fabric, the sum result of directional fabrics imposed by primary flow lineation, welding, and (if relevant) rheomorphism. AMS is a more sensitive indicator of fabric elements within welded tuffs than conventional methods, and usually yields primary flow azimuth estimates. Detailed study of a single densely welded tuff sample demonstrates that the overall AMS fabric is insensitive to the relative abundances of fiamme, matrix and lithics within individual drilled cores. AMS determinations on a welded-tuff dyke occurring in a choked vent in the Trans-Pecos Texas volcanic field reveals a consistent fabric with a prolate element imbricated with respect to one wall of the dyke, while total magnetic susceptibility and density exhibit axially symmetric variations across the dyke width. The dyke is interpreted to have formed as a result of agglutination of the erupting mixture on a portion of the conduit wall as it failed and slid into the conduit, followed by residual squeezing between the failed block and in situ wallrock. Irrespective of the precise mechanism, widespread occurrence of both welded-tuff dykes and point-welded, aggregate pumices in pyroclastic deposits may imply that lining of conduit walls by agglutionation during explosive volcanic eruptions is a common process.

  8. Calc-alkaline mafic rocks of the Black Dyke Formation: Remnants of the final activity of a submerged Permian volcano

    SciTech Connect

    Blein, O.; Lapierre, H.; Pecher, A. ); Schweickert, R.A. . Dept. of Geological Science)

    1993-04-01

    The Permian Black Dyke Fm., which occurs as large tectonic slices within the Luning allochthon in the Excelsior Mountains, NV, forms an E-W trending anticline at Black Dyke Mountain. The 800-m thick stratigraphic succession consists of volcanic and pyroclastic rocks overlain conformably by volcaniclastic sediments. Along the northern limb of the anticline, the rocks consist of mafic porphyritic lavas, breccias, and graded and ungraded pyroclastic beds. The sedimentary unit consists of thick volcaniclastic turbidites overlain by conglomerates, sandstones, and mudstones. Along the southern limb of the anticline, the sequence is replaced by reworked breccia, tuffs, and sandstones. Mafic plutonic rocks occur as xenoliths in the lavas and breccias, and as coeval plugs intruding the section. Gabbros show cumulate or porphyritic textures and are composed of amph, cpx, and zoned plag. Their Ti/V (14.5--15) and Nb/Y (0.25--0.3) ratios fall in the range commonly found in calc-alkaline rocks. Diorite porphyry shows high Al[sub 2]O[sub 3], ZrO[sub 2], and REE abundances indicating that this rock is more fractionated. Basalts and andesites are plag-cpx-opx phyric. They often include glomeroporphyritic clots of cpx with amph coronas. Some rocks exhibit fluidal textures. Both volcanic and plutonic rocks show homogeneous geochemical features and similar crystallization sequences: Fe-Ti oxides---->plag---->opx + cpx----> brown zoned hbl, suggesting that they are cogenetic. Thus, the lower part of the Black Dyke Fm. likely represents the final products formed in a calc-alkaline magma chamber because pyroclastic rocks prevail over lava flows and abundant early crystal cumulates occur as plugs or as inclusions in the lavas and breccias.

  9. 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

  10. Sentinel-1 TOPS interferometry for geophysical applications: Dyke intrusion imaged during 2014 Pico do Fogo eruption

    NASA Astrophysics Data System (ADS)

    Gonzalez, Pablo J.; Marinkovic, Petar; Samsonov, Sergey; Hooper, Andrew; Larsen, Yngvar; Wright, Tim

    2015-04-01

    apply Sentinel-1 TOPS-InSAR to illuminate the deformation accompanying a recent volcanic eruption at Pico do Fogo volcano, Fogo (Cape Verde). The detected deformation is consistent with a shallow near-vertical dyke intrusion, which fed the fissure eruption. The modelling of the deformation interferograms do not seem affected largely by the variable LoS vector, in this case. The presented results prove the potential of Terrain observation by progressive scans (TOPS) interferometry for geophysical applications, in particular using ESA Sentinel-1 mission.

  11. Mineral Chemistry of Silicate Phases From the Summit Creek Stock, Southeastern British Columbia: Evidence for Associated "Xenolith" Origin and Dyke Emplacement

    NASA Astrophysics Data System (ADS)

    Morrison, C. A.; Owen, J. P.

    2009-05-01

    The Summit Creek stock is a Mid-Cretaceous aged granitic intrusion that is located within the Cordilleran Omineca belt in the southeastern corner of British Columbia. Included within the stock are numerous xenoliths of intermediate composition that range in size from 5cm to 2m, as well as a prominent 1m-wide mafic dyke. According to the QAP diagram, the stock is classified as a muscovite-biotite monzogranite, with a typical sample containing 35% quartz, 25% plagioclase, 30% K-feldspar, 7% biotite, 2% muscovite, and 1% accessory phases. Minor accessory phases identified in this study include pyrite, molybdenite, apatite, magnetite, ilmenite, monazite, and zircon. Samples collected from the stock proper are predominantly equigranular; however the xenoliths are porphyritic and contain phenocrysts of both quartz and plagioclase, as well as glomerophyric aggregates of biotite. New investigation into the mineral chemistry of the stock, xenoliths, and dyke indicates that the xenoliths have a strong geochemical similarity to the main body of the stock. Plagioclase feldspar compositions from the xenolith overlap with those from the stock, and REE abundances in the stock and the xenoliths are indistinguishable (LREE 100x chondrite; HREE 10x chondrite). In thin section, the boundary between the xenoliths and the stock is very irregular, and protruding grains of plagioclase and biotite can be found piercing into both the granitic host, as well as into the xenolith itself. This evidence suggests that these inclusions are better termed autoliths rather than xenoliths, as it appears that they are derivatives of the same parent magma as the main stock. The mafic dyke differs in both mineralogy and geochemistry from the stock, and is characterized by low SiO2 content (48.98 wt.%), high REE abundances (30-40x chondrite), presence of rare euhedral hornblende, and greater variation in mineral chemistry. Samples from the dyke contain plagioclase with cores ranging from bytownite to

  12. A New Occurrence of Alkaline Magmatism on the Kola Peninsula: An Agpaitic Dyke in the Kandalaksha Region.

    NASA Astrophysics Data System (ADS)

    Akimenko, Mariya; Kogarko, Lia; Sorokhtina, Natalia; Kononkova, Natalia; Mamontov, Vladimir

    2015-04-01

    A new occurrence of alkaline dyke magmatism was discovered in 2010 during the geological works performed by the Murmansk Geological Prospecting Expedition in the "Mokhnatye Roga" area located 55 km to the southeast of the Kovdor massif (67°15' N, 31°30' E). The "Mokhnatye Roga" area is located in the Ensk segment of the northwestern part of the Belomorian mobile belt. We performed a complete petrological and geochemical description of the sections in Holes 19 and 24, which reveal one of the largest dykes in the area. The dyke, with a length of ≈4 km and a width of ≈160 m, has an eastern orientation with steep dipping (60°-90°) to the north. The thickness of Quaternary deposits ranges from 0.8 to 4.0 m; alkaline rocks occur in the range of 4.0-93.9 m being followed by host amphibole-biotite gneiss with interbeds of plagioamphibolite (AR2 mt) along the section. Among the major minerals of the dyke are the minerals of the lamprophyllite group (20-25 vol %), aegirine-augite (10-15 vol %), enigmatite (10-15 vol %), nepheline (10-15 vol %), orthoclase (15-20 vol %), alkaline amphibole (5-10 vol %), and astrophyllite (up to 5 vol %). The minor minerals are represented by shcherbakovite, sodalite, natrolite, barite, Mn carbonate, ilmenite, rutile, sphalerite, and goethite. The texture of the rock is porphyric: the groundmass is composed of finegranular nepheline and orthoclase, which are observed as individual large euhedral crystals as well. In addition, large phenocrysts are represented by the minerals of the lamprophyllite, enigmatite, pyroxene, and alkaline amphibole groups. Based on the generally accepted classifications [1], the studied agpaitic rock may be related to nepheline syenite; according to the mineral and chemical compositions, it is close to syenite of the Niva massif [2] located 35 km to the northeast from the "Mokhnatye Roga" area. Agpaitic syenite of the "Mokhnatye Roga" area is extremely enriched in dispersed and rare lithophile elements. The

  13. Xenoliths of Phl- Ol breccia and lamproite- like dykes in Udachanaya pipe

    NASA Astrophysics Data System (ADS)

    Ashchepkov, Igor; Ntaflos, Theodoros; Samsonov, Gerasim; Mityukhin, Sergei; Khmelnikova, Olga

    2013-04-01

    Probe laser system (analyst S.V. Palessky). The Cpx from the contact zone from the last sample show the incline REE pattern with LREE to 100 and hump near Pr. The incompatible element (IK) are more plat near 70 C1 with depression in Nb -Ta. The REE patterns for phlogopite are more inclined. Phls as well as bulk rock demonstrate inflected in Gd patterns consisting from two highly inclined parts suggesting mixing of two highly evolved liquids. Spiderdiagrams show continuous PhlL enrichment in IK (smaller in HFSE and Pb) and extremely high Ba, Rb (1000C1). The Cr- low garnet megacryst show elevated LREE and high HREE and moderate enrichment in IK. Phl-Ol rocks represent the last stage dyke stage of H2O rich melts evolution close to kimberlite II which produced Phl metasomatism in the lithosphere base (Ashchepkov et al., 2012, 2013). RBRF grant 11-05-00060.

  14. 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

  15. Electromagnetic induction in a conductive strip in a medium of contrasting conductivity: application to VLF and MT above molten dykes

    NASA Astrophysics Data System (ADS)

    Davis, Paul M.

    2014-11-01

    Very low frequency (VLF) electromagnetic waves that penetrate conductive magma-filled dykes generate secondary fields on the surface that can be used to invert for dyke properties. The model used for the interpretation calculates currents induced in a conductive strip by an inducing field that decays exponentially with depth due to the conductivity of the surrounding medium. The differential equations are integrated to give an inhomogeneous Fredholm equation of the second kind with a kernel consisting of a modified Bessel function of the second kind. Numerical methods are typically used to solve for the induced currents in the strip. In this paper, we apply a modified Galerkin-Chebyshev method, which involves separating the kernel into source and field spectra and integrating the source terms to obtain a matrix equation for the unknown coefficients. The incident wave is expressed as a Chebyshev series. The modified Bessel function is separated into a logarithmic singularity and a non-singular remainder, both of which are expanded in complex Chebyshev polynomials. The Chebyshev coefficients for the remainder are evaluated using a fast Fourier transform, while the logarithmic term and incident field have analytic series. The deconvolution then involves a matrix inversion. The results depend on the ratio of strip-size to skin-depth. For infinite skin-depth and a singular conductivity distribution given by τ_0 a/√{a^2 - z^2 } (where τ0 is the conductance, a is the half-length and z the distance from the centre), Parker gives an analytic solution. We present a similar analytic series solution for the finite skin-depth case, where the size to skin depth ratio is small. Results are presented for different ratios of size to skin depth that can be compared with numerical solutions. We compare full-space and half-space solutions. A fit of the model to VLF data taken above a magma filled dykes in Hawaii and Mt Etna demonstrates that while properties such as depth to top

  16. 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.

  17. Ultrapotassic dykes in the Moldanubian Zone and their significance for understanding of the post-collisional mantle dynamics during Variscan orogeny in the Bohemian Massif

    NASA Astrophysics Data System (ADS)

    Kubínová, Šárka; Faryad, Shah Wali; Verner, Kryštof; Schmitz, Mark; Holub, František

    2017-02-01

    We report mineral textures, geochemistry and age relations of two ultrapotassic dykes from a dyke swarm in the Western part of the Moldanubian Zone at contact to the Teplá-Barrandian Block. The dykes have orientation almost perpendicular to the NNE-SSW trending Central Bohemian plutonic complex and cross cut metamorphic foliation in basement gneisses and migmatites. Based on mineral compositions and geochemistry, the dykes show close relations to Mg-K syenite plutons in the Moldanubian Zone. The two dykes are vaugnerite and syenite in compositions and contain talc pseudomorphs after olivine within a fine-grained matrix that consists of K-feldspar, phlogopite with small amounts of clinopyroxene and accessory quartz, apatite, titanite and sulphides of Fe, Cu, Ni. The syenite porphyry dyke cross cuts the vaugnerite. It contains quartz phenocrysts and comparing to vaugnerite has lower modal content of talc pseudomorphs. The vaugnerite and syenite porphyry have high K2O (6 to 7 wt.%) and mg-number (0.66-0.74), but low CaO and Na2O contents. The vaugnerite is markedly rich in P2O5 (> 2 wt.%) and comparing to syenite porphyry has higher amount of mantle-incompatible elements (e.g. Rb, Cs, Ba, Pb, Th, U), V and Cr. ID-TIMS analyses on titanite in vaugnerite and on zircon in syenite porphyry yielded 338.59 ± 0.68 and 337.87 ± 0.21 Ma, respectively. Mineral and bulk rock chemistry of the dykes indicates that the source magma was formed by a low degree of partial melting of a highly anomalous domain in the upper mantle which subsequently fractionated and was contaminated with crustal material during its ascent. Formation of ultrapotassic magma is explained by transcurrent shear zones in the mantle lithosphere that occurred due to block rotation and post-collisional mantle dynamics initiated by slab break-off and asthenosphere upwelling into the Moldanubian accretionary complex during the Variscan Orogeny.

  18. 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

  19. 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.

  20. Petrogenesis of Mesoproterozoic lamproite dykes from the Garledinne (Banganapalle) cluster, south-western Cuddapah Basin, southern India

    NASA Astrophysics Data System (ADS)

    Rao, N. V. Chalapathi; Atiullah; Kumar, Alok; Sahoo, Samarendra; Nanda, Purnendu; Chahong, Ngazimpi; Lehmann, B.; Rao, K. V. S.

    2016-04-01

    We report mineral chemistry and whole-rock major and trace-element geochemistry for a recent find of Mesoproterozoic (~1.4 Ga) lamproites from the Garledinne (Banganapalle) cluster, south-western part of the Paleo-Mesoproterozoic Cuddapah Basin, southern India. The Garledinne lamproites occur as WNW-ESE-trending dykes that have undergone varying degree of pervasive silicification and carbonate alteration. Nevertheless, their overall texture and relict mineralogy remain intact and provide important insights into the nature of their magmas. The lamproite dykes have porphyritic to weakly porphyritic textures comprising pseudomorphed olivine macrocrysts and microphenocrysts, titanian phlogopite microphenocrysts, spinel having a compositional range from chromite to rarely magnesiochromite, Sr-rich apatite and niobian rutile. The Garledinne and other Cuddapah Basin lamproites (Chelima and Zangamarajupalle) collectively lack sanidine, clinopyroxene, potassic richterite, and titanite and are thus mineralogically distinct from the nearby Mesoproterozoic lamproites (Krishna and Ramadugu) in the Eastern Dharwar Craton, southern India. The strong correlation between various major and trace elements coupled with high abundances of incompatible and compatible trace elements imply that alteration and crustal contamination have had a limited effect on the whole-rock geochemistry (apart from K2O and CaO) of the Garledinne lamproites and that olivine fractionation played an important role in their evolution. The Garledinne lamproites represent small-degree partial melts derived from a refractory (previously melt extracted) peridotitic mantle source that was subsequently metasomatised (enriched) by carbonate-rich fluids/melts within the garnet stability field. The involvement of multiple reservoirs (sub-continental lithospheric mantle and asthenosphere) has been inferred in their genesis. The emplacement of the Garledinne lamproites is linked to extensional events, across the various

  1. 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

  2. Petrogenesis and tectonic implications of the Neoproterozoic Datian mafic-ultramafic dykes in the Panzhihua area, western Yangtze Block, SW China

    NASA Astrophysics Data System (ADS)

    Yang, Yi-Jin; Zhu, Wei-Guang; Bai, Zhong-Jie; Zhong, Hong; Ye, Xian-Tao; Fan, Hong-Peng

    2017-01-01

    Mafic-ultramafic dykes are important geological markers that can punctuate the onset of crustal extension during the breakup of a continent and provide valuable information on the mantle source. This study reports secondary ion mass spectroscopy zircon and baddeleyite U-Pb ages, elemental and Nd isotopic data for the Datian mafic-ultramafic dykes in the Panzhihua area, western Yangtze Block, SW China. Two kinds of rocks are confirmed: the picritic rock and the dolerite. Based on petrographic and geochemical features, the dolerite dykes are further subdivided into two groups: Group I mafic and Group II mafic dykes, which emplaced at 760 Ma (zircon U-Pb) and 800 Ma (zircon and baddeleyite U-Pb), respectively. All samples from the picritic rocks and the Group I mafic rocks show the features of high-Ti and alkaline basaltic magma in composition as well as "humped" trace element patterns, which are similar to those of typical alkaline basalts associated with continental rifts except for the slightly negative Nb-Ta anomalies. The Group II mafic rocks display the features of low-Ti and tholeiitic magma, moderately enriched in LILE and LREE, and characterized by distinctively negative Nb-Ta anomalies. The primary magmas of the picritic rocks and the Group I mafic rocks were generated from ca 25 % partial melting of an OIB-like, Nd isotopically depleted but incompatible elements relatively enriched mantle source within a garnet stable field. The Group II mafic rocks crystallized from crustal contaminated mafic magmas that were derived from a spinel-bearing sub-continental lithospheric mantle source, because of low ratios of La/Yb, Ti/Y and Sm/Yb. Geochemical features suggest that these groups of mafic-ultramafic dykes were formed in a continental rift setting, but derived from different mantle sources. In combination with other Neoproterozoic igneous rocks in the western margin of Yangtze Block, it is suggested that the Datian mafic-ultramafic dykes in the Panzhihua area

  3. Petrological and geochemical constraints on the origin of mafic dykes intruding the composite Kaçkar Pluton from the eastern Blacksea magmatic arc, NE Turkey

    NASA Astrophysics Data System (ADS)

    Aydin, Faruk; Oguz, Simge; Baser, Rasim; Uysal, Ibrahim; Sen, Cüneyt; Karsli, Orhan; Kandemir, Raif

    2015-04-01

    Geological, petrographical and geochemical data of mafic dykes intruding the composite Kaçkar Pluton from the eastern Blacksea magmatic arc (EBMA), NE Turkey, provide new insights into the nature of the metasomatizing agents in subcontinental lithospheric mantle beneath the region during the late Mesozoic-early Tertiary. Mafic dykes from the Çaykara and Hayrat (Trabzon), and also Ikizdere (Rize) areas from the northern margin of the EBMA consist of basalts, dolerites, lamprophyres (basic member) and lesser basaltic andesites and trachyandesites (evolved member). All dykes have no deformation and metamorphism. The outcrops of these dykes vary, with thickness from 0.2 to 10 m. and visible length from 3 to 20 m. In general, the mafic dykes dip steeply and cut directly across the Kaçkar Pluton, and show NW- and NE-trending, roughly parallel to the orientations of the EBMA main faults. Most of the dyke samples display subaphyric to porphyritic texture with phenocrysts of plagioclase (up to 10%), clinopyroxene (5-20%), amphibole (5-15%), and some contain variable amount of biotite (5-20%), lesser quartz (1-2%), and minor euhedral zircon, apatite and Fe-Ti oxides. The basic members of the mafic dykes have SiO2 of 44.1-51.9%, MgO of 4.5-12.1%, and TiO2 >mostly 0.8% (up to 2.3%) with K2O+Na2O of 1.3-6.6% with mostly subalkaline character. They are relatively high in mg-number (0.45-0.73) and transition metals (V=171-376 ppm, Co=22-45 ppm, Ni=3-148 ppm, and Sc=21-49 ppm). The evolved members of the dykes exhibit relatively higher SiO2 (57.1-60.2%) and K2O+Na2O (5.6-9.0%), and lower MgO (2.2-5.9%) and TiO2 (0.5-0.8%) contents than those from the basic dykes. Also, these samples have slightly low mg-number (0.41-0.65) and transition metals (V=99-172 ppm, Co=9-22 ppm, Ni=1-43 ppm, and Sc=9-20 ppm). In the Harker diagrams, all samples of the mafic dykes form a continuous array, and exhibit similar geochemical characteristics. In general, SiO2 inversely correlates with MgO, Fe

  4. 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.

  5. Mesoproterozoic mafic and carbonatitic dykes from the northern margin of the North China Craton: Implications for the final breakup of Columbia supercontinent

    NASA Astrophysics Data System (ADS)

    Yang, Kui-Feng; Fan, Hong-Rui; Santosh, M.; Hu, Fang-Fang; Wang, Kai-Yi

    2011-01-01

    The North China Craton (NCC) has figured prominently in recent reconstructions on the Paleoproterozoic supercontinent Columbia. Here we report abundant carbonatitic and mafic dykes from around the giant Bayan Obo rare earth element deposit in the northern margin of the NCC, and present geochemical and isotope geochronological data. The carbonatite (1354 ± 59 Ma) and mafic dykes (1227 ± 60 Ma) have comparable whole rock Sm-Nd isochron ages and Sr-Nd isotope compositions, suggesting a common source characteristic. Their geochemical characters including major and trace elements as well as REE patterns also attest to a common tectonic environment of magma generation and emplacement within a continental margin rift. The extensive mafic and carbonatitic magmatisms are associated with an extensional event that resulted in the formation of the Bayan Obo rift in the northern margin of the NCC, which we correlate with the final stages of fragmentation of the Columbia supercontinent amalgam.

  6. Rejuvenation of deeper magma reservoirs during differentiation: an example recorded in a post-plutonic dyke swarm S-Adamello (N-Italy)

    NASA Astrophysics Data System (ADS)

    Hurlimann, N.; Nandedkar, R.; Muntener, O.; Ulmer, P.

    2012-04-01

    The Adamello Batholith (42-29 Ma) is located in the Northern Italian Alps. It intruded into the Southern Alpine basement and its Permo-Triassic cover. In the Southern part a series of late dykes intruded into gabbroic and mainly tonalitic plutonic bodies. Models for volcanic eruptions of intermediate to silicic magmas are associated with the intrusion of fresh mafic magma into a magma reservoir, triggering eruption of the resident more evolved magma. Here we present an example of a series of post-plutonic dykes ranging from picro-basalts to dacites that indicates rejuvenation processes. Distinct phases of magma intrusion are documented by compositionally distinct dykes. Various degrees of magma mingling are widespread in this sequence. Primitive primary magmas occur as picro-basaltic dykes that are consistent with mantle-separation conditions of 28 kbar and 1370° C constrained, by multiple saturation experiments (Ulmer 1988). More evolved magmas in the same dyke swarm are homogeneous amphibole-plagioclase-phyric basaltic-andesites to dacites, which are almost devoid of mingling textures. Textures and mineral zoning patterns indicate a continuous differentiation process for these intermediate magmas at mid-crustal depth. In contrary, the mingled magmas display amphibole textures from pristine to complete pseudomorphs now present as clinopyroxene. Plagioclase and amphibole show reverse zoning and the common occurrence of bands or cores with sieve textures, indicating resorption processes of crystals related to the interaction with high-temperature mafic magma. Chilled margins and liquid apophyses of the mingled basalts and basaltic-andesites show crystallization of microphenocrysts of olivine+clinopyroxene+plagioclase at the emplacement level. In strongly mingled parts of the dykes resorbed amphibole is overgrown by fresh amphibole corresponding in composition to the microphenocrysts. Trace-element partition-coefficients between the cryptocrystalline matrix and

  7. 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

  8. Surface displacements on faults triggered by slow magma transfers between dyke injections in the 2005-2010 rifting episode at Dabbahu-Manda-Hararo rift (Afar, Ethiopia)

    NASA Astrophysics Data System (ADS)

    Dumont, S.; Socquet, A.; Grandin, R.; Doubre, C.; Klinger, Y.

    2016-01-01

    The rifting episode that occurred in Dabbahu-Manda-Hararo (Ethiopia) between 2005 and 2010 during which 14 dyke intrusions were emitted, was a unique opportunity to study interactions between tectonic deformation and magmatic processes. While magmatism has been shown to control primarily the spatial and temporal distribution of dyke intrusions during this accretion sequence, the role of faults in accommodating plate spreading in rift segments is poorly understood. During interdyking periods, transient ground deformation due to magma movement is generally observed. Investigating such a small-scale deformation and in particular the movement along faults during these periods will help understanding the factors that trigger fault movement in magmatic rifts. We analyse fault activity during three interdyking periods: 2006 December-June (d0-d1), 2007 January-July (d5-d6) and 2009 November-January (d10-d11). The time-space evolution of surface displacements along ˜700 faults is derived from pairs of ascending and descending SAR interferograms. Surface slip distributions are then compared with codyking ground deformation fields. The results show that faults are mainly activated above the areas affected by magma emplacement during interdyking periods. A detailed analysis of brittle deformation during the six months following the 2005 September intrusion shows asymmetric deformation on the rift shoulders, with significant opening on faults located to the west of the dyke. We explain this feature by the activation of westward dipping pre-existing faults, with block rotations in between. In addition, we observe that the strip encompassing the activated faults narrows by 30 per cent from co- to interdyking period. This suggests that magma keeps migrating to shallower depths after the dyke intrusion. During a rifting episode, activation of faults in a pre-existing fracture network therefore seems to be mainly controlled by deep magma processes.

  9. 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.

  10. Pluton-dyke relationships in a Variscan granitic complex from AMS and gravity modelling. Inception of the extensional tectonics in the South Armorican Domain (France)

    NASA Astrophysics Data System (ADS)

    Turrillot, P.; Faure, M.; Martelet, G.; Chen, Y.; Augier, R.

    2011-11-01

    The Carnac granitic Complex (South Armorican Domain, Western France) was emplaced during Late Carboniferous times in the deepest Variscan unit, roofed by two major extensional shear zones. Through the acquisition and interpretation of field data, Anisotropy of Magnetic Susceptibility and gravity data, emphasized by petrological and structural observations, we address the emplacement model and possible magmatic processes involved between dyking to massive plutonism in a synkinematic context. Gravity modelling highlights an overall eastward thinning of the pluton, and several deep zones in the western part of the complex, interpreted as the pluton feeder zones. The internal granitic fabric, developed in a sub-solidus state, shows marked planar-linear anisotropy, consistent with a vertical shortening in the WNW-ESE regional stretching regime and eastward magma spreading. This study documents the occurrence of numerous NNE-SSW trending dykes within the eastern part of the pluton, suggesting that this granitic Complex formed by the coalescence of dykes oriented perpendicular to the regional stretching direction, and thus interpreted as large-scale “tension gashes”. The synkinematic character of the Carnac Complex intrusion, recently dated at ca. 319 ± 6 Ma, thus times the inception of the late-orogenic extensional deformation experienced in the whole South Armorican Domain.

  11. 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.

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

    USGS Publications Warehouse

    Wicks, C.; 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.

  13. 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.

  14. Mineralogy and geochemistry of alkaline basic dykes from the northern Indian plate: signs of more than one episode of rifting and associated magmatism

    NASA Astrophysics Data System (ADS)

    Sajid, Muhammad; Andersen, Jens; Arif, Mohammad

    2016-04-01

    Rift related magmatism during Permian time in the northern margin of Indian plate, north-west Pakistan is shown by the occurrence of roughly linear array of alkaline rocks in the region. The constituent rocks include alkali granites, granodiorites, nepheline syenites, carbonatites and dykes of basic composition. The field relations, mineralogy and whole rock geochemistry of these basic dykes has been investigated. Significant textural and mineralogical distinctions have divided the basic dykes into a) dolerite and b) epidote amphibolites, cross cutting other alkaline rocks and pre-Permian rocks in the region. Clinopyroxene having augitic composition is a major mineral in dolerite, however, it is completely absent in epidote amphibolites. Amphiboles in dolerites are brown coloured having pargasitic composition while it is green to light green in colour having the composition of magnesio-hornblende in epidote amphibolites. Compositionally different types of olivine are present in dolerites while it is absent in epidote amphibolites. Intra-plate tectonic settings for both the rock types has been interpreted by Hf-Ta-Th and FeO-MgO-Al2O3 discrimination plots. Lower Zr/Nb ratio (<10) and K/Ba ratio (amid 20-40) for both the rock types further show their affinity to within-plate magmatism. Dolerites show depletion in REEs and other incompatible elements as compared to epidote amphibolites. The equilibrium partial melting models from primitive mantle using Dy/Yb, La/Yb, Sm/Yb, La/Sm and Nb/Y ratios show that both of these dykes originate form spinel lherzolite mantle. However, the degrees of partial melting from mantle is different i.e. epidote amphibolite show smaller degree (<5%) of partial melting of mantle than the dolerites (<10%). The contrasting geochemistry suggests that both of these dykes originated from heterogeneous mantle in two pulses with different degrees partial melting followed by fractional crystallization. Compositional zoning in plagioclase and

  15. Magmatism and metamorphism at the sheeted dyke-gabbro transition zone: new insight from beerbachite from ODP/IODP Hole 1256D and Oman ophiolite

    NASA Astrophysics Data System (ADS)

    Python, Marie; Abily, Bénédicte; France, Lydéric

    2014-05-01

    During IODP Expedition 335, two-pyroxenes bearing granulites (beerbachites) were extensively recovered as drilling cuttings at the gabbro-sheeted dyke transition zone of ODP Hole 1256D (East Pacific Rise, 6°44.163'N, 91°56.061'W). This lithology results from high-temperature metamorphism of previously hydrothermally altered diabases, basalts and/or gabbros; the heat source likely stems from the melt lens located at the top of the magmatic chambers imaged along present-day fast-spreading ridges. This lithology, associated with gabbroic bodies, characterises the transition zone between the sheeted dyke complex and the uppermost gabbroic section and represents the interface between magmatic and hydrothermal convecting systems in an oceanic crust formed at fast-spreading ridges. Samples acquired during IODP Exp. 335 show a particularly high degree of recrystallisation and are characterised by the absence of hydrous phases like amphibole, suggesting very high-T metamorphism. The Beerbachites mineral chemical characteristics are rather homogeneous compared to gabbros or dolerite from the sheeted dyke but pyroxenes Mg#, Ti, Al and Cr contents as well as the anorthite content of plagioclase are closer to gabbro than dolerite. This similarity may be explained by two hypothesis: either beerbachites in Hole 1256D are metamorphosed gabbros, or they underwent a melt-rock reaction process with the gabbros parental magma and were re-equilibrated at high temperature until their mineral composition become similar to that of gabbros. The gabbro-sheeted dyke transition zone in the Oman ophiolite is also outlined by the presence of high grade metamorphic rocks. Fine grained granulites and amphibolites that may be derived from the transformation of altered sheeted dyke diabases are in direct contact with fresh gabbroic and troctolitic bodies which are themselves cross-cut by dolerite dykes. The observation of textures show that high-T recrystallisation occurred in the fine grained

  16. Geochronologic and geochemical constraints of the petrogenesis of Permian mafic dykes in the Wuding area, SW China: Implications for Fe-Ti enrichment in mafic rocks in the ELIP

    NASA Astrophysics Data System (ADS)

    Fan, Hong-Peng; Zhu, Wei-Guang; Bai, Zhong-Jie; Yang, Yi-Jin

    2017-02-01

    Mafic dykes are widely distributed and well preserved in the Wuding area, SW China. The dykes are composed of fine-grained diabases, which are further subdivided into two groups (Group I and Group II). The rocks from Group I have relatively higher MgO (4.95-6.16 wt%) and lower TiO2 (2.26-2.78 wt%) contents than those from the Group II rocks (MgO = 4.04-4.58 wt%; TiO2 = 4.09-4.55 wt%). Two baddeleyite ages of 264 ± 3 Ma and 256 ± 5 Ma from the Wuding dykes suggest that the ages of these dykes are similar to the plutonic bodies and the associated volcanic rocks of the Emeishan large igneous province (ELIP). The compositions and isotopic signatures of the dykes are also similar to those of the ELIP volcanic rocks, indicating derivation from the same magmatic event at 260 Ma. The primary melts of the Wuding dykes were originated by partial melting of a long-term depleted OIB-like mantle source. The Group I dykes were mainly formed by wallrock assimilation and fractional crystallization processes. The magmas parental to the Group II rocks were much more evolved than the magma parental to the Group I rocks and probably produced by wallrock assimilation and fractional crystallization of the parent magma of the Group I rocks. The increasing enrichment of Fe and Ti from the Group I to the Group II rocks were attributed to a fractional crystallization process which may be an epitome of enrichment of Fe and Ti in the Fe-Ti rich mafic intrusions of the ELIP.

  17. Integrated Approach (Geophysics and Remote Sensing) to identify Water-bearing Dyke Swarms and Fractured Basement in the Sinai Peninsula, Egypt

    NASA Astrophysics Data System (ADS)

    Mohamed, L.; Sultan, M.; Ahmed, M. E.; Sauck, W.; Abouelmagd, A. A.; Chouinard, K.

    2012-12-01

    An integrated approach utilizing Very Low Frequency (VLF) and magnetic field surveying and temporal remote sensing data including: (1) Advanced Space Borne Thermal Emission and Reflection (ASTER) data, (2) European Remote Sensing (ERS-1 and ERS-2) radar imagery, and (3) Tropical Rainfall Measuring Mission (TRMM) was used to delineate water-bearing sub-vertical shear zones within the basement complex of the Sinai Peninsula. The following steps were undertaken: (1) the shear zones and dyke swarms within the basement complex were delineated using false color ASTER band and band ratio images; (2) the spatial and temporal precipitation events over the basement complex were then identified from TRMM data, and (3) finally, observations extracted from temporal radar and thermal ASTER bands were used to identify the water-bearing shear zones and dyke swarms. A fracture or dyke was deemed to be water bearing if: (1) it witnessed a large increase in its reflectivity and emissivity compared to its surroundings following a precipitation event, and maintained such differences for periods ranging from days to months. Field observations and VLF investigations were then applied to test the validity of our satellite-based methodologies for locating targeted aquifer types and for refining the satellite-based selections. The VLF detects conductive water-saturated subvertical breccia zones in bedrock. Thirty two VLF transects were collected in September of 2011 and July of 2012 along with 10 magnetic profiles at the same VLF locations. Both VLF and magnetic transects were acquired along a traverse perpendicular to the dike orientations with station separations ranging from 10 to 25 m. The VLF receiver (T-VLF) measures the distortion of the normally horizontal electromagnetic flux lines by local electrical conductors. At each VLF station, and for each frequency used, the following were measured: the tilt of the electromagnetic field, from the horizontal (given in percentage), the

  18. Composition of the ultramafic-mafic contact interval of the Great Dyke of Zimbabwe at Ngezi mine: Comparisons to the Bushveld Complex and implications for the origin of the PGE reefs

    NASA Astrophysics Data System (ADS)

    Maier, W. D.; Määttää, S.; Yang, S.; Oberthür, T.; Lahaye, Y.; Huhma, H.; Barnes, S.-J.

    2015-12-01

    The Great Dyke contains the world's second largest platinum resource after the Bushveld Complex. Isotopic and trace element data from the interval straddling the contact between the Ultramafic and Mafic Sequences of the Great Dyke indicate a less enriched composition than in the Bushveld Complex (Great Dyke: Sri 0.7024-0.7028, εNd mostly - 1 to + 1, Ce/Sm 2-6; Bushveld: Sri 705-0.709, εNd - 5 to - 7, Ce/Sm 5-15). These data are interpreted to reflect relatively moderate amounts of contamination of the Great Dyke parent magma. All analyzed isotopes show little variation across the Main Sulfide Zone and the ultramafic-mafic contact. This corroborates earlier work by other researchers that the Great Dyke crystallized from a single magma type. Mixing of compositionally distinct magmas, proposed to have caused sulfide melt saturation in the Bushveld Complex, seemingly played little or no role in the formation of the PGE mineralization in the Main Sulfide Zone, and neither did enhanced crustal contamination of specific magma batches. Instead, sulfide melt saturation of the magma was likely triggered by silicate fractionation. The mechanism of concentration of the sulfide melt remains uncertain, but theoretical considerations suggest that phase sorting in response to slumping of crystal mushes, possibly caused by chamber subsidence, played an important role. This model is consistent with the highly irregular, undulating nature of the contact between the mafic and ultramafic zones of the intrusion, in the hanging wall of the Main Sulfide Zone.

  19. Dyke-Davidoff-Masson Syndrome With Cerebral Hypometabolism and Unique Crossed Cerebellar Diaschisis in 18F-FDG PET/CT.

    PubMed

    Demir, Yusuf; Sürücü, Erdem; Çilingir, Vedat; Bulut, Mehmet Deniz; Tombul, Temel

    2015-09-01

    A 23-year-old man with Dyke-Davidoff-Masson syndrome (DDMS) was admitted to the hospital with increasing frequency of epileptic seizures. Physical examination revealed mental retardation, left facial asymmetry, and left-sided spastic hemiparesis. Dysdiadochokinesia on the left upper limb was detected, and there was no dysmetria. MRI confirmed the well-known radiological features of DDMS. PET/CT demonstrated cerebral and contralateral cerebellar hypometabolism. We present DDMS with crossed cerebellar diaschisis, which was demonstrated by PET/CT.

  20. First cross-correlated measurements of magma dynamics and degassing during a dyke eruption at Piton de la Fournaise hot spot volcano, Reunion island

    NASA Astrophysics Data System (ADS)

    Allard, P.; La Spina, A.; Tamburelllo, G.; Aiuppa, A.; Coquet, A.; Brenguier, F.; Coppola, D.; Di Muro, A.; Burton, M. R.; Staudacher, T.

    2011-12-01

    Piton de la Fournaise (PdF), in the western Indian Ocean, is a very active hot spot basaltic volcano whose eruptions (1-2 per year on average) are well anticipated by the local seismic-geodetic monitoring network. Here we report on the first cross-correlated measurements of seismic tremor, magmatic gas composition (OP-FTIR absorption spectroscopy and in situ MultiGas analysis plus filter-pack sampling), gas fluxes (DOAS) and magma extrusion rate (space-borne MODIS data) during a 2-weeks long dyke eruption at PDF in October 2010. Precursory seismic signals indicated dyke ascent in a few hours from a reservoir located at ~2.5 km beneath the summit crater. After an initial burst coinciding with eruptive fissure opening, both the tremor amplitude, lava extrusion rate and SO2 flux coherently decreased during the first week of eruption. The co-emitted magmatic gases, whose composition varied slightly over time, were found to have a high water content (95-98 mol %), high SO2/HCl and low CO2/SO2, HCl/HF and Cl/Br ratios, consistent with a hydrous hot spot mantle source. By comparing gas fluxes with the magma co-extrusion rate and available melt inclusion data, we infer an essentially syn-eruptive (closed system) degassing for sulfur, chlorine and fluorine during the first half of the eruption. In contrast, additions of CO2 (previously accumulated or/and bubbling differentially) and H2O (external contribution from the hydrothermal system?) are required to explain the gas composition. Differential CO2 bubbling is supported by high frequency correlations between the CO2/HCl ratio and seismic tremor. The second part of the eruption was marked by a spectacular decoupling between re-increasing seismic tremor and declining lava extrusion, indicating a key control of tremor and eruptive activity by differential (open system) gas bubbling across the feeder dyke. This was associated with an increasing contribution of the low-frequency (1-3 Hz) spectral band to the tremor amplitude

  1. Integrated methodologies for the 3d survey and the structural monitoring of industrial archaeology: the case of the Casalecchio di Reno Dyke, Italy

    NASA Astrophysics Data System (ADS)

    Bitelli, Gabriele; Girelli, Valentina A.; Vittuari, Luca; Zanutta, Antonio

    2010-05-01

    The concept of "Industrial Archaeology" was introduced in the 1950s in England in order to consider the branch of Archaeology that, in integration with engineering, architecture and economics, studies the industrial past, with the purpose of document, protect and exploite the industrial-cultural heritage. The systematic study of this kind of structures and artefacts need a wide range approach, that starts from the investigation about the object historic fonts until its complete qualitative and quantitative description, also considering the characteristics of the surrounding territory. This task often needs the integration of different survey techniques for data capturing and processing, in order to perform the 3D modeling and to analize the structural deformations of manufactured articles. The paper presents the surveying and monitoring activities on the important structure of the Casalecchio di Reno dyke, near Bologna. The first historic notes on the dyke are very old; they are dated back to the I millenium A. D. and report the news of a wooden barrage of the Reno canal. The construction of the actual structure is in the period 1360-1367 and suffered during the centuries numerous interventions and restores. The surveying activities on the dyke were realized in 2005-2006 and 2009 and involved different techniques (classical topography, high precision geometric levelling, range-based method by terrestrial laser scanning, digital photogrammetry, thermal imagery) integrated together in a unique local reference system, in order to study the stability and the movements of the structure in a established period of time and to realize a 3D model. Together with detail surveys on the single parts of the structure, an analysis at a larger territorial scale was performed by aerial photogrammetry, either using current imagery and historical data. The topographic measurements with traditional differential techniques have achieved a very high level precision and the realized

  2. A 1.78 Ga large igneous province in the North China craton: The Xiong'er Volcanic Province and the North China dyke swarm

    NASA Astrophysics Data System (ADS)

    Peng, Peng; Zhai, Mingguo; Ernst, Richard E.; Guo, Jinghui; Liu, Fu; Hu, Bo

    2008-03-01

    The 1.78 Ga Xiong'er Volcanic Province (XVP) and coeval North China giant mafic Dyke Swarm (NCDS) are the most important magmatic events occurring after the amalgamation of the North China craton (NCC). The XVP consists of 3-7 km of extrusive volcanics and some feeder dykes/sills located along the southern margin of the NCC and extending over an area > 0.06 M km 2. Compositions vary from basalt to rhyolite, but are predominantly intermediate in terms of silica content. There are also minor sedimentary intercalations and pyroclastic units. The sedimentary interlayers indicate an environment changing from continental-facies to oceanic-facies up-section. The XVP is characterized by fractional crystallization from an EM I type mantle source, and both continental arc (Andean-type) and rift environments have been proposed. The NCDS is widespread in the central NCC with an outcrop area > 0.1 M km 2, and are exposed at variable depths up to 20 km (deepest in the north). Dyke compositions vary from basalt to andesite and dacite, but are dominantly mafic, and comprise two series of magmatism. Previous studies revealed that the NCDS recorded assimilation and fractional crystallization of an EM I type magma source, with a minor DM contribution in the younger magmas. Both syn-collisional and intra-continental anorogenic environments have been proposed. Spatial and petrogenic correlations suggest a cogenetic relationship between the NCDS and XVP, and considered together, they define a Large Igneous Province (LIP) of > 0.1 M km 2 in area and > 0.1 M km 3 in volume, which is also notable for its continuous compositional range from mafic to felsic (with no gap at intermediate compositions). The petrology is explained by a common magma source that undergoes a silica-poor and iron-enriched fractionation trend at depth followed by a silica-rich and iron-poor fractionation trend in shallow-level magma conduits (dykes) and surface lavas. A mantle plume is favored as the cause of this

  3. 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

  4. Chromian spinels in mafic ultramafic mantle dykes: Evidence for a two-stage melt production during the evolution of the Oman ophiolite

    NASA Astrophysics Data System (ADS)

    Python, Marie; Ceuleneer, Georges; Arai, Shoji

    2008-11-01

    This paper describes a comprehensive study of the chromian spinels present in mafic-ultramafic dykes cropping out along the mantle section of the Oman ophiolite. We studied about 1100 samples in thin section and with the electron microprobe. Chromian spinel is almost ubiquitous in primitive dykes (high-Mg# troctolites and pyroxenites) and less common in more differentiated ones (olivine gabbros and gabbronorites). The Cr#, TiO 2 content, and other compositional parameters are well correlated to the nature and composition of the co-genetic silicate assemblage. Chromian spinel composition contributes to establish that the mantle dykes of Oman are more or less evolved cumulates that crystallised from two main types of primary melts: tholeitic melt similar to Mid-Ocean Ridge basalts (MORB; 0.45 < Cr# < 0.63; 0.3 < Mg# < 0.6; TiO 2 up to2 wt.%), and more silicic melts issued from a highly depleted mantle source, similar to boninitic-andesitic melts that preferentially form in subduction zone settings (0.35 < Cr# < 0.80; 0.1 < Mg# < 0.7; TiO 2 up to 0.2 wt.%). The chromian spinel composition presents a higher variability than the associated silicates and allows us to further unravel the petrological evolution and segmentation of the Oman ophiolite. The composition of chromian spinel in mantle dykes and in the spatially related residual harzbugites display well correlated variations at the scale of the Oman ophiolite. This shows that these two lithologies share a common magmatic history, even if, strictly speaking, they cannot be related through direct parent-daughter relationships. The Cr# is on average higher, and the TiO 2 lower in the NW than in the SE, consistent with an increasing influence of "marginal" magmatic processes in the NW, while the southeastern area has petrological characteristics closer to those of an "open" ocean. In this southeastern part, compositional variations of the chromian spinel are correlated to structural characteristics related to the

  5. 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.

  6. 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

  7. Effect of small potassium-rich dykes on regional gamma-spectrometry image of a potassium-poor volcanic complex: A case from the Doupovské hory Volcanic Complex, NW Czech Republic

    NASA Astrophysics Data System (ADS)

    Zuzana, Skácelová; Vladislav, Rapprich; Bedřich, Mlčoch

    2009-10-01

    Basaltic rocks with low K, U and Th contents dominate the entire Volcanic Complex of the Doupovské hory Mts. Significant potassium anomaly exceeding 1.5 atomic wt.% of potassium over an area of 4 × 8 km and 2 atomic wt.% of potassium over an area of 2 × 6 km was defined by airborne gamma-ray spectrometry above the central part of the Doupovské hory Volcanic Complex. The following detailed field study, supported by field and laboratory gamma-spectrometry measurements and geochemical analyses of rock samples, resulted in discovery of a swarm of potassium-rich trachytic dykes. The existence of such highly-differentiated rocks in the volcanic complex was unknown till present. These dykes are commonly less than 1 m wide, but their potassium content varies between 4 and 8 atomic wt.%. Owing to this high-K composition and relative abundance of dykes, the dyke rocks significantly modify the regional pattern of gamma-spectrometry data. The potassium anomaly cannot be explained by the presence of Flurbühl intrusive body dominated by ijolites and essexites, as all these rocks are poor in K, with potassium typically not exceeding 1.5 wt.%. On the other hand, much more extensive intermediate trachybasaltic lavas with K content varying within the range 1.8-3 wt.% cause only minor or undetectable anomalies.

  8. U-Pb (ID-TIMS) baddeleyite ages and paleomagnetism of 1.79 and 1.59 Ga tholeiitic dyke swarms, and position of the Rio de la Plata Craton within the Columbia supercontinent

    NASA Astrophysics Data System (ADS)

    Teixeira, Wilson; D'Agrella-Filho, Manoel S.; Hamilton, Mike A.; Ernst, Richard E.; Girardi, Vicente A. V.; Mazzucchelli, Maurizio; Bettencourt, Jorge S.

    2013-08-01

    The Tandilia Terrane (southernmost fringe of the Rio de la Plata Craton) is an igneous and metamorphic complex produced by an accretionary orogeny (2.25-2.02 Ga). Calc-alkaline acidic dykes with E-W strike and a major shear zone with similar orientation are related with the late orogeny stage, as supported by field relations. In a previous study the acid dykes gave 40A-39Ar ages of 2007 ± 24 Ma to 2020 ± 24 Ma. A N and NW trending tholeiitic dyke swarm (Tandil swarm) is also present in the Tandilia Terrane. One sample from the NW-trending subset previously gave a U-Pb (ID-TIMS) baddeleyite age of 1588 ± 11 Ma. New precise U-Pb (ID-TIMS) baddeleyite dating of both N- and NW-trending Tandil dykes yielded crystallization ages of 1589 ± 3 Ma, 1588 ± 3 Ma and 1588 ± 3 Ma. Significantly older tholeiitic dykes known as the Florida swarm occur in the Northern Rio de la Plata Craton, for which a U-Pb (ID-TIMS) baddeleyite age of 1790 ± 5 Ma was previously reported. Consequently intermittent rifting (1.79, 1.59 Ga) took place after tectonic stabilization of the late Paleoproterozoic lithosphere (proto-Rio de la Plata Craton). The available geochemical data for the 1.59 Ga Tandil dykes define low- and high-TiO2 trends, although, only the low-TiO2 subgroup is firmly dated. Both the Tandil and Florida dykes have geochemical and Nd-Sr characteristics consistent with derivation from heterogeneous mantle sources that underwent metasomatic effects. The Tandil dykes may be linked with the 1.57 ± 0.02 Ga Capivarita anorthosite which occurs to the east of the northern part of the craton. Correlatives on other crustal blocks may include those in Baltica such as bimodal rock association (including the Breven-Hällefors and Åland-Åboland diabase dykes) and in the reconstructed Gawler Craton/NW Laurentia dolerites, bimodal magmatism and IOCG deposits. Contemporary within-plate bimodal associations are also present in the SW Amazonian Craton. Paleomagnetic data for the 1790 Ma

  9. 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

  10. Petrology of continental tholeiitic magmas forming a 350-km-long Mesozoic dyke swarm in NE Brazil: Constraints of geochemical and isotopic data

    NASA Astrophysics Data System (ADS)

    Ngonge, Emmanuel Donald; de Hollanda, Maria Helena Bezerra Maia; Archanjo, Carlos José; de Oliveira, Diógenes Custódio; Vasconcelos, Paulo Marcosde Paula; Muñoz, Patrício Rodrigo Montecinos

    2016-08-01

    The Ceará Mirim dyke swarm (northeastern Brazil) is composed of Cretaceous tholeiites with plagioclase, clinopyroxene (± olivine), Fe-Ti oxides and pigeonite in their groundmass. These tholeiites have been subdivided into three groups: high-Ti olivine tholeiites, evolved high-Ti tholeiites (TiO2 ≥ 1.5 wt.%; Ti/Y > 360), and low-Ti tholeiites (TiO2 ≤ 1.5 wt%; Ti/Y ≤ 360), with all exhibiting distinct degrees of enrichment in incompatible elements relative to Primitive Mantle. Negative Pb anomalies are found in all three groups, while Nb-Ta abundances similar to those of OIB-type magmas are found in the olivine tholeiites, with moderate to high depletions being observed, respectively, in the evolved high-Ti and low-Ti tholeiites. The low-Ti tholeiites exhibit some contamination with crustal (felsic) materials during ascent. The initial isotopic compositions of the olivine tholeiites show uniform and unradiogenic 87Sr/86Sr (~ 0.7035-0.7039) combined with (in part) radiogenic 143Nd/144Nd and 206Pb/204Pb (> 19.1) ratios, which together reveal a likely contribution of FOZO (FOcalZOne) component in their genesis. The other tholeiite groups show variable Sr-Nd ratios with relatively consistent 206Pb/204Pb ratios clustering towards an isotopically enriched mantle (EM1) component. Taken in conjunction with the Nb, this enriched signature reflects the involvement of a subduction-modified lithospheric mantle in the source of the evolved high-Ti and low-Ti tholeiites. Thus, we propose that FOZO and EMI components coexisted (including minor mixing with E-MORB magmas) and contributed in varying extents to the generation of the Ceará-Mirim dyke swarm primary melts, which segregated at 75 to 60 km in depth around the garnet-spinel facies transition zone. The mechanism that promoted melting was most likely non-plume related. We suggest that plate-boundary forces linked to the opening of the Atlantic Ocean promoted passive rifting and that the resulting asthenospheric

  11. Age and origin of fluorapatite-rich dyke from Baranec Mt. (Tatra Mts., Western Carpathians): a key to understanding of the post-orogenic processes and element mobility

    NASA Astrophysics Data System (ADS)

    Gawęda, Aleksandra; Szopa, Krzysztof; Chew, David; Klötzli, Urs; Müller, Axel; Sikorska, Magdalena; Pyka, Paulina

    2016-10-01

    On the southeastern slope of the Baranec Mount in the Western Tatra Mountains (Slovakia) an apatite-rich pegmatite-like segregation was found in the subvertical fault zone cutting metapelitic rocks. Two zones: felsic (F) and mafic (M) were found, differing in mineral assemblages and consequently in chemistry. Fluorapatite crystals yield a LA-ICP-MS U-Pb age of 328.6 ± 2.4 Ma. A temperature decrease from 634 °C to 454 °C at a pressure around 500 to 400 MPa with oxygen fugacity increasing during crystallization are the possible conditions for formation of the pegmatite-like segregation, while secondary alterations took place in the temperature range of 340 - 320 °C. The Sr-Nd isotope composition of both apatite and whole rock point toward a crustal origin of the dike in question, suggesting partial melting of (P, F, H2O)-rich metasedimentary rocks during prolonged decompression of the Tatra Massif. The original partial melt (felsic component) was mixed with an external (F, H2O)-rich fluid, carrying Fe and Mg fluxed from more mafic metapelites and crystallizing as biotite and epidote in the mafic component of the dyke.

  12. Note: Modified π-type Butterworth-Van Dyke model for dual-mode Lamb-wave resonator with precise two-port Y-parameter characterizations

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Hong, Yan; Goh, Wang Ling; Mu, Xiaojing

    2016-10-01

    Dual-mode Lamb-wave resonator has become a powerful component for clock reference and sensing applications, enabling efficient compensations of temperature effects, concurrent measurements of multiple environmental parameters, etc. An equivalent circuit model for the dual-mode Lamb-wave resonator is indispensable as it provides a means as well as being an effective tool for evaluating device characteristics and to aid the designing of circuitry for the resonators. This could be the first time ever that an efficient equivalent-circuit model, i.e., modified π-type Butterworth-Van Dyke model for dual-mode Lamb-wave resonators is reported. Evaluated by experiments, this model attains noteworthy agreements on both the magnitudes and phases of Y11 and Y21 of the measurement results. Compared to literature, the proposed model is capable of modeling the dual resonances efficiently. Moreover, this work also proves more accurate when viewing the Y-parameters across a wide frequency range. The gained features of this model are most beneficial for the analysis of the dual-mode Lamb-wave resonator and also for the designing of circuits.

  13. 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.

  14. Nevus vascularis mixtus (cutaneous vascular twin nevi) associated with intracranial vascular malformation of the Dyke-Davidoff-Masson type in two patients.

    PubMed

    Ruggieri, Martino; Milone, Pietro; Pavone, Piero; Falsaperla, Raffaele; Polizzi, Agata; Caltabiano, Rosario; Fichera, Marco; Gabriele, Anna Lia; Distefano, Angela; De Pasquale, Rocco; Salpietro, Vincenzo; Micali, Giuseppe; Pavone, Lorenzo

    2012-11-01

    The term twin spotting refers to phenotypes characterized by the spatial and temporal co-occurrence of two (or more) different nevi arranged in variable cutaneous patterns, and can be associated with extra-cutaneous anomalies. Several examples of twin spotting have been described in humans including nevus vascularis mixtus, cutis tricolor, lesions of overgrowth, and deficient growth in Proteus and Elattoproteus syndromes, epidermolytic hyperkeratosis of Brocq, and the so-called phacomatoses pigmentovascularis and pigmentokeratotica. We report on a 28-year-old man and a 15-year-old girl, who presented with a previously unrecognized association of paired cutaneous vascular nevi of the telangiectaticus and anemicus types (naevus vascularis mixtus) distributed in a mosaic pattern on the face (in both patients) and over the entire body (in the man) and a complex brain malformation (in both patients) consisting of cerebral hemiatrophy, hypoplasia of the cerebral vessels and homolateral hypertrophy of the skull and sinuses (known as Dyke-Davidoff-Masson malformation). Both patients had facial asymmetry and the young man had facial dysmorphism, seizures with EEG anomalies, hemiplegia, insulin-dependent diabetes mellitus (IDDM), autoimmune thyroiditis, a large hepatic cavernous vascular malformation, and left Legg-Calvé-Perthes disease (LCPD) [LCPD-like presentation]. Array-CGH analysis and mutation analysis of the RASA1 gene were normal in both patients.

  15. Note: Modified π-type Butterworth-Van Dyke model for dual-mode Lamb-wave resonator with precise two-port Y-parameter characterizations.

    PubMed

    Wang, Yong; Hong, Yan; Goh, Wang Ling; Mu, Xiaojing

    2016-10-01

    Dual-mode Lamb-wave resonator has become a powerful component for clock reference and sensing applications, enabling efficient compensations of temperature effects, concurrent measurements of multiple environmental parameters, etc. An equivalent circuit model for the dual-mode Lamb-wave resonator is indispensable as it provides a means as well as being an effective tool for evaluating device characteristics and to aid the designing of circuitry for the resonators. This could be the first time ever that an efficient equivalent-circuit model, i.e., modified π-type Butterworth-Van Dyke model for dual-mode Lamb-wave resonators is reported. Evaluated by experiments, this model attains noteworthy agreements on both the magnitudes and phases of Y11 and Y21 of the measurement results. Compared to literature, the proposed model is capable of modeling the dual resonances efficiently. Moreover, this work also proves more accurate when viewing the Y-parameters across a wide frequency range. The gained features of this model are most beneficial for the analysis of the dual-mode Lamb-wave resonator and also for the designing of circuits.

  16. Petrology, 40Ar/39Ar age, Sr-Nd isotope systematics, and geodynamic significance of an ultrapotassic (lamproitic) dyke with affinities to kamafugite from the easternmost margin of the Bastar Craton, India

    NASA Astrophysics Data System (ADS)

    Rao, N. V. Chalapathi; Atiullah; Burgess, R.; Nanda, Purnendu; Choudhary, A. K.; Sahoo, Samarendra; Lehmann, B.; Chahong, Ngazipmi

    2016-04-01

    We report the mineralogy, bulk-rock geochemistry, 40Ar/39Ar (whole-rock) age and radiogenic (Sr and Nd) isotope composition of an ultrapotassic dyke from Sakri (Nuapada lamproite field) located at the tectonic contact between the easternmost margin of the Bastar craton and Eastern Ghats Mobile Belt, India. The Sakri dyke has a mineralogy which strongly resembles a lamproite sensu stricto (viz.,Ti-rich phlogopite, Na-poor diopside, Fe-rich sanidine, ulvospinel trend and Sr-rich apatite). However, its bulk-rock major element geochemical characteristics (viz., extreme silica-undersaturated nature) resemble sensu lato kamafugite from Toro Ankole, Uganda, East African Rift, and Alto Paranaiba Province, Brazil. The Sakri dyke also displays certain compositional peculiarities (viz., high degree of evolution of mica composition from phlogopite to biotite, elevated titanium and aluminum in clinopyroxene and significantly lower bulk Mg#) when compared to the ultrapotassic rocks from various Indian cratons. 40Ar/39Ar dating gave a plateau age of 1045 ± 9 Ma which is broadly similar to that of other Mesoproterozoic (i) lamproites from the Bastar and Bundelkhand cratons, and (ii) kimberlites from the Eastern Dharwar craton. Initial bulk-rock Sr (0.705865-0.709024) and Nd (0.511063-0.511154) isotopic ratios reveal involvement of an `enriched' source region with long-term incompatible element enrichment and a depleted mantle (TDM) Nd model age of 2.56 Ga straddling the Archaean-Proterozoic chronostratigraphic boundary. The bulk-rock incompatible trace element ratios (Ta/Yb, Th/Yb, Rb/Ba and Ce/Y) of the Sakri ultrapotassic dyke negate any significant influence of crustal contamination. Small-degree melting (1 to 1.5 %) of a mixed garnet-facies and spinel-facies phlogopite lherzolite can account for its observed REE concentrations. Whereas the emplacement of the Sakri ultrapotassic dyke is related to the amalgamation of the supercontinent of Rodinia, its overlapping geochemical

  17. 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

  18. Precursors to dyke-fed eruptions at basaltic volcanoes: insights from patterns of volcano-tectonic seismicity at Kilauea volcano, Hawaii

    NASA Astrophysics Data System (ADS)

    Bell, Andrew F.; Kilburn, Christopher R. J.

    2012-03-01

    To investigate the physical controls on volcano-tectonic (VT) precursors to eruptions and intrusions at basaltic volcanoes, we have analyzed the spatial and temporal patterns of VT earthquakes associated with 34 eruptions and 23 dyke intrusions that occurred between 1960 and 1983 at Kilauea, in Hawaii. Eighteen of the 57 magmatic events were preceded by an acceleration of the mean rate of VT earthquakes located close to the main shallow magma reservoir. Using a maximum-likelihood technique and the Bayesian Information Criterion for model preference, we demonstrate that an exponential acceleration is preferred over a power-law acceleration for all sequences. These sequences evolve over time-scales of weeks to months and are consistent with theoretical models for the approach to volcanic eruptions based on the growth of a population of fractures in response to an excess magma pressure. Among the remaining 40 magmatic events, we found a significant correlation between swarms of VT earthquakes located in the mobile south-flank of Kilauea and eruptions and intrusions. The behaviour of these swarms suggests that at least some of the magmatic events are triggered by transient episodes of elevated rates of aseismic flank movement, which could explain why many eruptions and intrusions are not preceded by longer-term precursory signals. In none of the 57 cases could a precursory sequence be used to distinguish between the approach to an eruption or an intrusion, so that, even when a precursory sequence is recognized, there remains an empirical chance of about 40% (24 intrusions from 57 magmatic events) of issuing a false alarm for an imminent eruption.

  19. 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.

  20. The 2005 Ilan earthquake doublet and seismic crisis in northeastern Taiwan: evidence for dyke intrusion associated with on-land propagation of the Okinawa Trough

    NASA Astrophysics Data System (ADS)

    Lai, Kuang-Yin; Chen, Yue-Gau; Wu, Yih-Min; Avouac, Jean-Philippe; Kuo, Yu-Ting; Wang, Yu; Chang, Chien-Hsin; Lin, Kuan-Chuan

    2009-11-01

    Northern Taiwan underwent mountain building in the early stage of the Taiwan orogeny but is currently subjected to post-collisional crustal extension. It may be related to gravitational collapse or to the rifting of the Okinawa Trough, which lies offshore northeastern Taiwan. The Ilan Plain, northeastern Taiwan, which is bounded by the normal fault systems and filled up with thick Pliocene-Pleistocene sedimentary sequences, formed under such an extension environment. Over there on 2005 March 5 two earthquakes with about the same magnitude (ML = 5.9) occurred within 68 s and produced intense aftershocks activity according to the records of Central Weather Bureau Seismic Network of Taiwan. We relocated the earthquake sequence by the three-dimension earthquake location algorithm with the newly published 3-D Vp and Vp/Vs velocity model, and determined the first-polarity focal mechanisms of the earthquake doublet. One major cluster of aftershocks which trends E-W and dips steeply to the south can be identified and picked up as a potential fault plane. The focal mechanisms of the two main shocks are both classified as normal type by first-polarity but strike-slip by centroid moment tensor inversion; however two methods both yield consistent E-W strike. Static coseismic deformation was additionally determined from Global Positioning System (GPS) daily solutions at a set of continuous GPS stations and from strong-motion seismographs. These data show NW-SE extension at high angle to the fault plane, which cannot be explained from a simple strike-slip double-couple mechanism. On the other hand, the small vertical displacements and steep fault plane cannot be explained from a simple normal event as well. We present from elastic dislocation modelling that the geodetic data are best explained by significant component of tensile source with centimetre-scale of opening on a 15-km-long fault extending from 1 to 13 km depth. We therefore interpret the crisis as the result of dyke

  1. Parasitic analysis and π-type Butterworth-Van Dyke model for complementary-metal-oxide-semiconductor Lamb wave resonator with accurate two-port Y-parameter characterizations

    NASA Astrophysics Data System (ADS)

    Wang, Yong; Goh, Wang Ling; Chai, Kevin T.-C.; Mu, Xiaojing; Hong, Yan; Kropelnicki, Piotr; Je, Minkyu

    2016-04-01

    The parasitic effects from electromechanical resonance, coupling, and substrate losses were collected to derive a new two-port equivalent-circuit model for Lamb wave resonators, especially for those fabricated on silicon technology. The proposed model is a hybrid π-type Butterworth-Van Dyke (PiBVD) model that accounts for the above mentioned parasitic effects which are commonly observed in Lamb-wave resonators. It is a combination of interdigital capacitor of both plate capacitance and fringe capacitance, interdigital resistance, Ohmic losses in substrate, and the acoustic motional behavior of typical Modified Butterworth-Van Dyke (MBVD) model. In the case studies presented in this paper using two-port Y-parameters, the PiBVD model fitted significantly better than the typical MBVD model, strengthening the capability on characterizing both magnitude and phase of either Y11 or Y21. The accurate modelling on two-port Y-parameters makes the PiBVD model beneficial in the characterization of Lamb-wave resonators, providing accurate simulation to Lamb-wave resonators and oscillators.

  2. 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

  3. 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.

  4. Hispanos en la EPA: Karen Milians

    EPA Pesticide Factsheets

    La diversidad de la fuerza laboral es importante para la Agencia de Protección Ambiental de EE.UU. (EPA, por sus siglas en inglés). Los empleados hispanos de la EPA contribuyen diariamente hacia la protección de la salud y el medio ambiente.

  5. The Ediacaran volcanic rocks and associated mafic dykes of the Ouarzazate Group (Anti-Atlas, Morocco): Clinopyroxene composition, whole-rock geochemistry and Sr-Nd isotopes constraints from the Ouzellarh-Siroua salient (Tifnoute valley)

    NASA Astrophysics Data System (ADS)

    Belkacim, Said; Gasquet, Dominique; Liégeois, Jean-Paul; Arai, Shoji; Gahlan, Hisham A.; Ahmed, Hassan; Ishida, Yoshito; Ikenne, Moha

    2017-03-01

    Belonging to the huge Ouarzazate volcanic Group that covered the whole Anti-Atlas during the late Ediacaran (580-545 Ma), the Tifnoute valley volcanic formations are mainly pyroclastic and show a large composition, from trachybasalt to rhyolite and are crosscut by dolerite dykes. The Tifnoute valley volcanic rocks are located within a rigid salient of the Anti-Atlas that gives them special extreme characteristics. Due to the heavy greenschist alteration that affects this volcanic group, we focused the more immobile elements, but as REE can also be affected, we used the composition of unaltered clinopyroxene crystals to determine the nature of these volcanic rocks. The clinopyroxene is an augite diopside in the basalt, an augite in the andesite and an augite-salite in the dolerite. Petrography of the Tifnoute mafic volcanic rocks and clinopyroxene compositions indicate the presence of two magmatic series: (i) older high-K calc-alkaline (alkali-calcic) andesite and basalt characterized by the early crystallization of Fe-Ti oxides and of the late fractionation of plagioclase, the modal proportion of the latter increasing from the basalt to the andesite and (ii) younger alkalic dolerite dykes. With clinopyroxene trace element compositions obtained using laser ablation ICP-MS, we calculated the composition of the melts in equilibrium with the pyroxenes. The volcanic rocks of the Tifnoute Valley have positive εNd570 (+1.7 to +5.0), low Sri (<0.7063), and NdTDM model ages ranging from 0.80 to 1.14 Ga, indicating a mostly depleted Neoproterozoic source with limited involvement of the Eburnian lithosphere for the Tifnoute magmas. This depleted source is the young lithospheric mantle for the alkali-calcic series and the asthenosphere for the younger alkalic series. The Tifnoute Valley volcanic rocks emplaced in a Pan-African transtensive post-collisional environment that evolved towards the major rifting event that will give rise to the Rheic ocean, in a similar way to what

  6. CERT tribal internship program. Final intern report: Karen Sandoval, 1996

    SciTech Connect

    1998-09-01

    This intern report consists of the workshop handbook for the Comprehensive Environmental and Natural Resource Management Planning workshop presented by the Council of Energy Resource Tribes. The workshop objectives were to foster and awareness of integrated resource management rationale; present the fundamental elements of an integrated approach; explain what distinguishes this approach from mainstream strategies; discuss how worldview and philosophy shape action and policy; present ways in which philosophical dexterity promotes effective management; and identify opportunities to engage and participate in integrated management. Resource articles presented at the meeting have been removed for separate processing for inclusion on the data base.

  7. CERT tribal internship program. Final intern report: Karen Sandoval, 1994

    SciTech Connect

    1998-09-01

    The purpose of the project was to: create a working relationship between CERT and Colorado State University (CSU); involve and create relationships among individuals and departments at CSU; empower Native communities to run their own affairs; establish programs for the benefit of Tribes; and create Native American Program Development Office at CSU. The intern lists the following as the project results: revised a Native American Program Development document; confirmation from 45 departments across campus for Summit attendance [Tribal Human Resource Development Summit]; created initial invitee list from CSU departments and colleges; and informed CERT and CSU staff of results. Much of the response from the campus community has been positive and enthusiastic. They are ready to develop new Native American programs on campus, but need the awareness of what they can do to be respectful of Tribal needs.

  8. Health and Human Rights in Karen State, Eastern Myanmar

    PubMed Central

    Davis, William W.; Mullany, Luke C.; Shwe Oo, Eh Kalu; Richards, Adam K.; Iacopino, Vincent; Beyrer, Chris

    2015-01-01

    Background Decades of conflict in eastern Myanmar have resulted in high prevalence of human rights violations and poor health outcomes. While recent ceasefire agreements have reduced conflict in this area, it is unknown whether this has resulted in concomitant reductions in human rights violations. Methods and Findings We conducted a two-stage cluster survey of 686 households in eastern Myanmar to assess health status, access to healthcare, food security, exposure to human rights violations and identification of alleged perpetrators over the 12 months prior to January 2012, a period of near-absence of conflict in this region. Household hunger (FANTA-2 scale) was moderate/high in 91 (13.2%) households, while the proportion of households reporting food shortages in each month of 2011 ranged from 19.9% in December to 47.0% in September, with food insecurity peaking just prior to the harvest. Diarrhea prevalence in children was 14.2% and in everyone it was 5.8%. Forced labor was the most common human rights violation (185 households, 24.9%), and 210 households (30.6%) reported experiencing one or more human rights violations in 2011. Multiple logistic regression analysis identified associations between human rights violations and poor health outcomes. Conclusion Human rights violations and their health consequences persist despite reduced intensity of conflict in eastern Myanmar. Ceasefire agreements should include language that protects human rights, and reconciliation efforts should address the health consequences of decades of human rights violations. PMID:26308850

  9. 77 FR 26766 - Karen L. Blyth: Debarment Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-07

    ... and sell seafood. She was also a co- owner, president, and chief executive officer of RF Inc. from on or about October 1, 2004, through on or about March 2007. RF Inc. also sold seafood, including...

  10. Women on the Edge of a Dyke-otomy.

    PubMed

    Hird, M J; Germon, J

    1999-01-01

    SUMMARY This paper considers some of the contradictions of authenticity as a defining feature of lesbian community in Aotearoa/ New Zealand. We sketch the genealogy of marginalization within the lesbian community through the development of subjectivity, community and political struggle for equality. To this end, we deconstruct three major, interrelated "problems" in speaking of lesbian politics: subjectivity, community and universality. At its broadest, the lesbian subject refers to any woman who desires women. But in practice such a "continuum" does not satisfactorily identify a bounded community. In articulating its voice, any community necessarily creates a governing discourse, thereby creating outsiders and insiders to that community. This paper explores the conditions under which the lesbian community has marginalized an "other" lesbian subject with particular reference to sexual practices and associations with heterosexuality in order to establish an authenticity of identity.

  11. "Why's a Nice Dyke like You Embracing This Postmodern Crap?"

    ERIC Educational Resources Information Center

    Lugg, Catherine A.

    2008-01-01

    In this article, I present a historical overview of the queer rights movement in the United States, from the late 1940s to today, weaving snapshots of my own life into the narrative, from living in the closet to being totally out, both personally and professionally. Because I was closeted at the beginning of my career, my research agenda did not…

  12. BRSCW Reference Set Application: Karen Abbott -University of Arkansas (2014) — EDRN Public Portal

    Cancer.gov

    Our earlier glycoproteomic studies have identified bisecting glycoslyation and core fucosylation changes on particular glycoproteins in endometrioid ovarian cancer tissues and plasma (Abbott et al, 2010, Proteomics). We have validated that these glycan changes occur on the same glycoproteins in serous ovarian cancer plasma using a lectin-pull down western blot assays. We would like to used pooled reference samples to develop a sensitive magnetic bead-based assay to detect these glycoproteins with bisecting and core fucosylation changes.

  13. Breast Reference Set Application: Karen Anderson-ASU (2014) — EDRN Public Portal

    Cancer.gov

    In order to increase the predictive value of tumor-specific antibodies for use as immunodiagnostics, our EDRN BDL has developed a novel protein microarray technology, termed Nucleic Acid Protein Programmable Array (NAPPA), which circumvents many of the limitations of traditional protein microarrays. NAPPA arrays are generated by printing full-length cDNAs encoding the target proteins at each feature of the array. The proteins are then transcribed and translated by a cell-free system and immobilized in situ using epitope tags fused to the proteins. Sera are added, and bound IgG is detected by standard secondary reagents. Using a sequential screening strategy to select AAb from 4,988 candidate tumor antigens, we have identified 28 potential AAb biomarkers for the early detection of breast cancer, and here we propose to evaluate these biomarkers using the EDRN Breast Cancer Reference Set.

  14. Breast Reference Set Application: Karen Abbott- University of Arkansas (2013) — EDRN Public Portal

    Cancer.gov

    We are evaluating whether detection of a tumor-specific N-linked glycosylation known as B 1,6 branched N-glycan present on the glycoprotein periostin in breast cancer will be useful as a new biomarker for the detection of breast cancer in patient plasma and serum. We have completed an initial study using samples with known inavasive ductal breast carcinoma diagnosis and the results look very promising. Therefore, we would like to proceed with our analysis of this potential biomarker for breast cancer diagnosis by analyzing the blinded samples in breast reference set 1.

  15. Freud, females, childbirth, and dissidence: Margarete Hilferding, Karen Horney, and Otto Rank.

    PubMed

    Balsam, Rosemary

    2013-10-01

    These three early psychoanalysts, who differed in important ways from Freud, each tried to shift his fundamental beliefs about women's bodies in basic developmental theory. This paper illustrates this point by elaborating their materials concerning the centrality of childbirth. One thematic aspect of Freud's disruptive fights with colleagues lay in his loyalty to phallocratic certainties. These problems still affect us, a century later, even in today's clinically pluralistic climate.

  16. Internet Links for Science Education: Student-Scientist Partnerships (edited by Karen Cohen)

    NASA Astrophysics Data System (ADS)

    Barden, Linda M.

    1998-10-01

    Plenum: New York, 1997. xx + 260 pp. Figs., tables, photos. 15 x 22.8 cm. ISBN 0-306-45558-7. $27.50. Science education is undergoing an upheaval more fundamental than the one that occurred in the aftermath of Sputnik. Research during the past 40 years has led to a radical change in the way we view children's learning of science. The National Science Education Standards (NSES) suggest a new model for teaching science based upon these research findings. Societal changes, particularly changes in business, have put pressure on schools to alter the emphasis of curricula from rote memory and individual competition to problem solving using a variety of technological skills and teamwork/team competition. This timely book addresses all these issues by describing projects that K-12 teachers can use to achieve the goals set forth by both NSES and business. It also provides scientists with examples of how they and their coworkers might better interact with K-12 science education to encourage a more scientifically literate society. Finally, it includes suggestions for future research in science education.

  17. Malaria and enterobiasis among Karen Long-neck tribe in Mae Hong Son Province.

    PubMed

    Nithikathkul, Choosak; Polseela, Panida; Poodendan, Wilawan; Brodsky, Marc; Rakprapapant, Derek; Chadchatreechan, Suparp; Phethleart, Aree; Sukthana, Yaowalark; Leemingsawat, Somjai

    2003-01-01

    In Thailand, Mae Hong Son Province is highly endemic for malaria. Knowing this, the local Health Department has introduced a program to educate local residents about the risk factors, in particular the dangers and symptoms of malaria. This study was conducted to evaluate these efforts, by determining the number of malaria infections in a segment of the population, and also by testing for enterobiasis among a group of its children. Two villages in Mae Hong Son Province were chosen for this purpose with a combined population of about 300. Of these, 195 were screened for malaria. Two subjects were diagnosed positive for malaria by microscopy. One of these two villages was chosen to screen for Enterobius vermicularis infection in children as well. Out of 69 stool samples, five (7%) showed infection with E. vermicularis: three with a low number of eggs (1-50), and two with a high number of eggs (>100). Compared with infection rates in similar studies, the results of this study indicate that the Health Department's efforts are meeting with relative success. The low prevalence of infection indicates that the villagers are using the information they have received to help combat infection.

  18. The petrogenesis of late Neoproterozoic mafic dyke-like intrusion in south Sinai, Egypt

    NASA Astrophysics Data System (ADS)

    Azer, M. K.; Abu El-Ela, F. F.; Ren, M.

    2012-08-01

    New field, petrographical and geochemical studies are presented here for the late Neoproterozoic Rimm intrusion (˜15 km long) exposed in the southern Sinai Peninsula, Egypt in the northernmost Arabian-Nubian Shield (ANS). Field relations indicate that the Rimm intrusion is younger than the surrounding metamorphic rocks and calc-alkaline syn-tectonic granodiorite and it was not affected by regional metamorphism. The anorogenic peralkaline granite of Gebel Serbal crosscuts the Rimm intrusion. The Rimm intrusion is made up of several consanguineous rock types with gradational contacts. It is composed chiefly of pyroxene-hornblende gabbro, hornblende gabbro and minor quartz diorite. The chemical composition of the mafic minerals indicated that the studied rocks derived from calc-alkaline mafic magma. Geochemically, the studied rocks are characterized by enrichment in LILE relative to HFSE and LREE relative to HREE [(Ce/Yb)N = 4.50-6.36]. Quartz diorite display slightly concave HREE pattern and slightly negative Eu-anomaly [(Eu/Eu*)n = 0.91] which may be the result of fractionation of amphibole and plagioclase from the source melt, respectively. The Rimm intrusion evolved from mafic mantle magma into different type rocks by fractional crystallization with minor crustal contamination. The initial magma corresponds to pyroxene-hornblende gabbro and the crystallization of hornblende was caused by slight H2O increase in magma after crystallization of near-liquidus clinopyroxene and Ca-rich plagioclase. Amphiboles geobarometer indicate that the gabbroic rocks of the Rimm intrusion crystallized at pressures between 4.8 and 6.4 Kb, while quartz diorite crystallized at 1.3-2.1 Kb. Crystallization temperatures range between 800 and 926 °C for the gabbros and between 667 and 784 °C for the quartz diorite. The Rimm intrusion represents a post-orogenic phase formed during the crustal thinning and extension of the Arabian-Nubian Shield.

  19. A resolution to recognize the Dyke Marsh Wildlife Preserve as a unique and precious ecosystem.

    THOMAS, 111th Congress

    Sen. Webb, Jim [D-VA

    2009-10-01

    05/07/2010 Resolution agreed to in Senate without amendment and with a preamble by Unanimous Consent. (consideration: CR S3429-3431; text as passed Senate: CR S3430) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation:

  20. Are eruptions from linear fissures and caldera ring dykes more likely to produce pyroclastic flows?

    NASA Astrophysics Data System (ADS)

    Jessop, D. E.; Gilchrist, J.; Jellinek, A. M.; Roche, O.

    2016-11-01

    Turbulent volcanic jets are produced by highly-energetic explosive eruptions and may form buoyant plumes that rise many tens of kilometres into the atmosphere to form umbrella clouds or collapse to generate ground-hugging pyroclastic flows. Ash injected into the atmosphere can be transported for many hundreds of kilometres with the potential to affect climate, disrupt global air travel and cause respiratory health problems. Pyroclastic flows, by contrast, are potentially catastrophic to populations and infrastructure close to the volcano. Key to which of these two behaviours will occur is the extent to which the mechanical entrainment and mixing of ambient air into the jet by large (entraining) eddies forming the jet edge changes the density of the air-ash mixture: low entrainment rates lead to pyroclastic flows and high entrainment rates give rise to buoyant plumes. Recent experiments on particle-laden (multi-phase) volcanic jets from flared and straight-sided circular openings suggest that the likelihood for buoyant plumes will depend strongly on the shape and internal geometry of the vent region. This newly recognised sensitivity of the fate of volcanic jets to the structure of the vent is a consequence of a complex dynamic coupling between the jet and entrained solid particles, an effect that has generally been overlooked in previous studies. Building on this work, here we use an extensive series of experiments on multi-phase turbulent jets from analogue linear fissures and annular ring fractures to explore whether the restrictive vent geometry during cataclysmic caldera-forming (CCF) eruptions will ultimately lead a relatively greater frequency of pyroclastic flows than eruptions from circular vents on stratovolcanoes. Our results, understood through scaling analyses and a one-dimensional theoretical model, show that entrainment is enhanced where particle motions contribute angular momentum to entraining eddies. However, because the size of the entraining eddies scales approximately with vent width, the extent of entrainment is reduced as the vent width becomes small in comparison to its length. Consequently, our work shows that for specified mass eruption rates, the high length-to-width ratio vents typical of CCF events are more likely to produce pyroclastic flows. We suggest that the enigmatic trend in the geological record for the largest CCF eruptions to produce pyroclastic flows is an expected consequence of their being erupted through continuous or piece-wise continuous caldera ring fractures.

  1. An application of the interpersonal models developed by Karen Horney and Timothy Leary to type A-B behavior patterns.

    PubMed

    Roemer, W W

    1987-01-01

    Using Horney's clinical concepts and Leary's circle matrix procedures, this study investigated the Type A and B patterns of personality. Significant findings showed the Type A-B continuum to represent two distinct poles, with the Type A direction reflecting the expansive personality pattern (power and aggressiveness) and the Type B direction reflecting the self-effacing pattern (helplessness and affiliation) for self-perceived roles. For behavioral roles, the power-versus-helplessness traits described the two contrasting directions of personality involvement. Three subgroups were identified for behavioral role in each A and B extreme group. The shift in affect between the ACL and MMPI instruments may reflect two factors: the degree of ambiguity set up by the nature of the tests and the responding "pull" of the individual, which was described as an "active" or "quiescent" form of the A and B patterns. Hence, it may be more effective to diagnose individuals in terms of a specific behavioral subtype and active or quiescent enactments. Three maladjustment indicators were investigated. Significant findings showed the A2 group as exhibiting increasing rigidity of behavioral role with lower Type A scores and the A1 group as exhibiting greater discrepancies with increasing Type A scores. The lack of discrepancy for the Type B groups may reflect a dysfunction in that these individuals may be stagnated in their work situations and complacent in the docile-dependent role. The three findings of behavioral subgroups, rigidity of role, and discrepancy were discussed as possible mediating psychosocial factors associated with coronary heart disease. Since this was the first major examination and use of Leary's model (to the author's knowledge) since the late 1950s, it is important to consider these results tentative and heuristic, until replications can be conducted. It is hoped that representative norms from diverse samples can be obtained for developing standard scores on Leary's circle matrix axes. The present study was limited by the narrow demographic characteristics of its subjects, who were mostly white-collar workers in professional, technical, or management positions.

  2. Very shallow dyke intrusion and potential slope failure imaged by ground deformation: The 28 December 2014 eruption on Mount Etna

    NASA Astrophysics Data System (ADS)

    Bonforte, Alessandro; Guglielmino, Francesco

    2015-04-01

    On 28 December 2014, eruptive activity resumed at Mount Etna with fire fountain activity feeding two lava flows on the eastern and southwestern upper flanks of the volcano. Unlike all previous summit activity, this eruption produced clear deformation at the summit of the volcano. GPS displacements and Sentinel-1A ascending interferograms were calculated in order to image the ground deformation pattern accompanying the eruption. The displacements observed by GPS depict a local ground deformation pattern, affecting only the upper part of the volcano. Despite snow cover on the summit, differential interferometry synthetic aperture radar (DInSAR) data allowed obtaining more detail on the ground deformation pattern on the upper eastern side of the volcano. Three-dimensional GPS displacements inversion located a very shallow NE-SW intrusion just beneath the New Southeast Crater. However, this model cannot justify all the deformation observed by DInSAR thus revealing a gravitational failure of the lava flow field.

  3. Slab and sediment melting during subduction initiation: granitoid dykes from the mantle section of the Oman ophiolite

    NASA Astrophysics Data System (ADS)

    Rollinson, Hugh

    2015-09-01

    New geochemical data are presented for a suite of tonalites, granodiorites, trondhjemites and granites intrusive into depleted mantle harzburgites of the Oman-UAE ophiolite. A detailed field, petrological and geochemical examination suggests that these `mantle granitoids' are the product of three processes: (a) the mixing of melts derived from both mafic and metasedimentary sources, (b) interaction with the mantle harzburgite host and (c) the fractional crystallisation of plagioclase, hornblende ± accessory phases. Geochemical data are used to characterise the identity of the protolith(s) by first screening the data for those samples which have experienced fractional crystallisation during emplacement. The resultant `reduced' data set has moderately fractionated REE, with small negative Eu anomalies and fractionated primitive mantle-normalised trace element patterns with high concentrations of fluid mobile elements and lower concentrations of HFS elements and with positive peaks for Rb and Pb and negative troughs for Ba, Nb, Sr and Ti. The character of the protolith was quantified using a melting model based upon a MORB-type basalt similar in composition to the Oman Geotimes lavas and a model using the MUQ (MUd from Queensland) global sediment composition (Kamber et al. Geochim Cosmochim Acta 69:1041-1058, 2005) both with an amphibolite/granulite facies mineralogy. The two compositions bracket the mantle granitoid data set with partial melts of the MORB source yielding trace element compositions lower than the granitoids, whereas melts of the MUQ source yield melts with compositions higher than the granitoids. Mixing of the calculated melt compositions indicates that the measured granitoid compositions represent between 10 and 30 % mixing of a metasedimentary melt into the melt of a mafic source. Current petrological, structural and geochronological data suggest a model for the origin of the Oman ophiolite in which it is formed by spreading above a subduction zone. The results of this study support this model in three ways: (a) trace element data show that the granitoids have interacted with the mantle, implying that they originated below the mantle section of the ophiolite and were emplaced into the mantle wedge from below; (b) a most probable setting for the melting of a sediment-basalt mix is in the upper part of a subducting slab; (c) the high temperature/shallow melting of the sediment and basaltic slab mix can only have been driven by the high temperatures of the overlying mantle wedge; this is most likely during subduction initiation. Thus, sediment melting during subduction initiation represents an important means of refertilising what is otherwise highly depleted mantle.

  4. Application of Ground Penetrating Radar Surveys and GPS Surveys for Monitoring the Condition of Levees and Dykes

    NASA Astrophysics Data System (ADS)

    Tanajewski, Dariusz; Bakuła, Mieczysław

    2016-08-01

    This paper analyses the possibility of using integrated GPS (Global Positioning System) surveys and ground penetrating radar surveys to precisely locate damages to levees, particularly due to the activity of small fossorial mammals. The technology of intercommunication between ground penetrating radar (GPR) and an RTK (Real-Time Kinematic) survey unit, and the method of data combination, are presented. The errors which may appear during the survey work are also characterized. The procedure for processing the data so that the final results have a spatial character and are ready to be implemented in digital maps and geographic information systems (GIS) is also described.

  5. Numerical model of the Stromboli volcano (Italy) including the effect of magma pressure in the dyke system

    NASA Astrophysics Data System (ADS)

    Apuani, T.; Corazzato, C.

    2009-02-01

    The Stromboli island, in the Aeolian archipelago (Italy), is one of the most active volcanoes in Europe. In the last 13,000 years, its growth has been complicated by four sector collapses affecting the NW flank, the latest of which resulting in the formation of Sciara del Fuoco (SdF) horseshoe-shaped depression. Slope instability phenomena are represented not only by giant deep-seated gravitational slope deformations, but also by more frequent large landslides, such as occurred in December 2002-January 2003, and shallow landslides, involving loose or weakly cemented deposits, that constitute a natural hazard and affect residential and tourists safety. It is noteworthy that in volcanic environment the instability factors are manifold and much more complex than in other non-volcanic contexts. This paper deals with the Stromboli NW flank instability, and focuses on the effects of magma pressure in the feeding system. Two main objectives have been pursued: (1) to test a methodological approach, in order to evaluate a complex instability process; (2) to contribute to the understanding of volcano deformation and collapse mechanisms and associated hazard. A numerical model was developed by the Finite Difference Method and the FLAC 4.0 code, considering a cross-section of the entire volcano, orthogonal to the SdF and including both subaerial and submerged slopes. The stability of the volcano was analysed under gravity alone, and by introducing the magma pressure effect, both related to magmastatic and overpressure components. The results indicate that gravity alone is not sufficient to affect the stability of the volcano slopes, nor is the magmastatic pressure component. If an excess magma pressure component is introduced, instability is produced in accordance with field evidences and recent slope dynamics.

  6. Social Networking and the School Adjustment of Karen Refugee Youth from Burma: Determining the Effects of Ethnic Identity, Bonding Social Capital, and Facebook Use

    ERIC Educational Resources Information Center

    Lewis, Lucy D.

    2013-01-01

    In 2011 alone, over 56,000 refugees were admitted to the United States and a third of these individuals were under the age of 18 (Martin & Yankay, 2012). Researchers have found that the social capital developed through close and confiding relationships is instrumental in the academic outcomes of refugee youth (Kia-Keating & Ellis, 2007;…

  7. Geochemistry of sapphirine-apatite-calcite-bearing gabbroic dykes from the Finero Phlogopite Peridotite (Ivrea-Verbano Zone): evidence for multistage interaction with the ambient peridotite

    NASA Astrophysics Data System (ADS)

    Tommaso, Giovanardi; Alberto, Zanetti; Maurizio, Mazzucchelli; Tomoaki, Morishita; Antonio, Langone

    2016-04-01

    The Finero Phlogopite-Peridotite (FPP) is a mantle unit outcropping in the northernmost tip of the Ivrea-Verbano Zone (IVZ, Southern Alps). It shows a virtually complete recrystallization due to pervasive to channelled melt migration. The pervasive metasomatism formed a main lithologic association constituted by phlogopite harzburgites associated to phlogopite pyroxenites (mainly olivine-websterites, websterites and orthopyroxenites). These lithologies are also rich in amphibole and do not show significant chemical gradients among them (Zanetti et al., 1999). The channelled migration stages formed dunite bodies, which sometimes contain stratiform chromitites and, more rarely, pyroxenite layers similar to those associated to phlogopite harzburgite. The FPP also shows a discrete number of other, subordinate rock-types, which are characterised by the presence of apatite usually associated to carbonates (i.e. calcite or dolomite) and exhibit marked modal and chemical gradients with respect to the host phlogopite harzburgite. Examples of these lithologies are apatite-dolomite-bearing wehrlites and harzburgites (e.g. Zanetti et al. 1999; Morishita et al., 2008), apatite-calcite zircon-syenites and hornblendites. Ar-Ar amphibole analysis and U-Pb zircon and apatite data return Triassic ages for these rocks, which have been considered to document the time of melt/fluid injection. Notwithstanding the apparent mineralogical and chemical differences with the main lithologic sequences, apatite-carbonates-bearing rocks have been frequently interpreted as cogenetic to phlogopite harzburgites. To debate the petrogenesis of these rocks, a detailed field, petrological and geochemical investigation has been carried out on a swarm of apatite-calcite-bearing gabbroic veins that randomly cut the main lithologic association. Preliminary investigation evidenced as these veins show complex metasomatic haloes and a symmetric internal layering, characterised by crystallisation of magmatic sapphirine (Giovanardi et al., 2013). The mineral assemblage of the veins is dominated by titanian pargasite towards the host peridotite and by plagioclase at the vein centre. The veins also present phlogopite and spinel. Field and petrographic evidence, major and trace element data and the O isotopic composition of such gabbroic veins indicate that they formed at shallow mantle conditions by multistage fractional crystallisation of a migrating melt unrelated to those forming phlogopite harzburgites. Besides, local strong enrichments in LILE, LREE and 18O in vein minerals confirm that such melt was deeply modified by interaction with the host phlogopite peridotite. The genetic relationships with other intrusive events recorded by the FPP and the associated crustal sequence will be addressed with the aim of placing new constraints on the petrologic and geodynamic evolution of the IVZ. Giovanardi, T., Morishita, T., Zanetti, A., Mazzucchelli, M., Vannucci, R. (2013). Igneous sapphirine as a product of melt-peridotite interactions in the Finero Phlogopite-Peridotite Massif, Western Italian Alps. European Journal of Mineralogy 25, 17-31. Morishita, T., Hattori, K.H., Terada, K., Matsumoto, T., Yamamoto, K., Takebe, M., Ishida, Y., Tamura, A., Arai, S. (2008). Geochemistry of apatite-rich layers in the Finero phlogopite-peridotite massif (Italian Western Alps) and ion microprobe dating of apatite. Chemical Geology 251, 99-111. Zanetti, A., Mazzucchelli, M., Rivalenti, G., Vannucci, R. (1999). The Finero phlogopite-peridotite massif: an example of subduction-related metasomatism. Contributions to Mineralogy and Petrology 134, 107-122.

  8. Was the Devonian geomagnetic field dipolar or multipolar? Palaeointensity studies of Devonian igneous rocks from the Minusa Basin (Siberia) and the Kola Peninsula dykes, Russia

    NASA Astrophysics Data System (ADS)

    Shcherbakova, V. V.; Biggin, A. J.; Veselovskiy, R. V.; Shatsillo, A. V.; Hawkins, L.; Shcherbakov, V. P.; Zhidkov, G. V.

    2017-02-01

    Defining variations in the behaviour of the geomagnetic field through geological time is critical to understanding the dynamics of Earth's core and its response to mantle convection and planetary evolution. Furthermore, the question of whether the axial dipole dominance of the recent palaeomagnetic field persists through the whole of Earth's history is fundamental to determining the reliability of palaeogeographic reconstructions and the efficacy of the magnetosphere in shielding Earth from solar wind radiation. Previous palaeomagnetic directional studies have suggested that the palaeofield had a complex configuration in the Devonian period (419-359 Ma). Here we present new palaeointensity determinations from rocks aged between 408 and 375 Ma from the Minusa Basin (southern Siberia), and the Kola Peninsula to investigate the strength of the field during this enigmatic period. Palaeointensity experiments were performed using the thermal Thellier, microwave Thellier, and Wilson methods on 165 specimens from 25 sites. Six out of eight successful sites from the Minusa Basin and all four successful sites from the Kola Peninsula produced extremely low palaeointensities (< 10 μT). These findings challenge the uniformitarian view of the palaeomagnetic field: field intensities of nearly an order of magnitude lower than Neogene values (except during relatively rare geomagnetic excursions and reversals) together with the widespread appearance of strange directions found in the Devonian suggest that the Earth's field during this time may have had a dominantly multipolar geometry. A persistent, low intensity multipolar magnetic field and associated diminished magnetosphere would increase the impact of solar particles on the Earth's magnetosphere, ionosphere and atmosphere with potential major implications for Earth's climate and biosphere.

  9. Sequential emplacement of sheeted plutons and sill-dyke complexes: implication on crustal anatexis and lifespan of hydrothermal/geothermal systems

    NASA Astrophysics Data System (ADS)

    Dini, A.

    2014-12-01

    Depending on initial melt composition, magma volumes, transfer rates, depth of emplacement and tectonic conditions, granite magmas can follow different crystallization paths leading to complex patterns of magmatic fluid/heat release and water-rock interaction in the host rocks at the emplacement level. In the case of multi-pulse magmatic complexes, several contact metamorphic and hydrothermal effects can overlap through time on a relatively small crustal portion. The net result of the described complex evolution is a magmatic system, where magmatic fluid exsolution, heat flow and triggering of meteoric fluid convection cells follow cyclically transient patterns with strong implication on ore forming processes and geothermal field lifespan. Detailed field mapping, coupled with petrographic-geochronologic-geochemical-isotopic data on Late Miocene-Pleistocene granite intrusions in Tuscany provided new insights on melting processes occurred in the roots as well as on paleo-hydrothermal circuits triggered at the roof of the intrusive complexes. Tuscan granite intrusions were constructed incrementally by amalgamation (sheeted plutons) and/or multilayer dispersion (sills and laccoliths) of different magma pulses, sequentially produced as the Apennine fold belt was progressively thinned, heated and intruded by mafic magmas. Partial melting was probably triggered by multiple, small-sized mafic intrusions, that allowed temporary overstepping of dehydration melting reactions into the already pre-heated crust. Dilution in time of the magmatic activity prevented melt homogenization at depth, allowing the formation at the emplacement level of multiple, isotopically distinct, intrusive sheets instead of a single, homogeneous, hybrid pluton. This could be also one of the major key factors explaining the prolonged hydrothermal activity recorded in this area by both fossil (Plio-Pleistocene ore deposits) and active (Larderello geothermal field) systems.

  10. 75 FR 9028 - Quarterly Publication of Individuals, Who Have Chosen To Expatriate, as Required by Section 6039G

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ... KAREN-HELENA SABRINA HASSAN ABDELMONEM HAYDAY ADRIAN C ] HAYDAY SANDRA ANN HELBIG INGO M. HELD BETTINA... PAHLSSON REX HENRIK PAHR-IVERSEN KAREN-HELENA SABRINA HART PAK CHIN YONG PAK SUN YUL PAK YONG MAE PARK...

  11. 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

    ...) 554-1404; e-mail address: TSCA-Hotline@epa.gov . For technical information contact: Karen Chu... address: chu.karen@epa.gov . SUPPLEMENTARY INFORMATION: I. Does this Action Apply to Me? A list...

  12. An Analytical History of Provider Organization Support within Navy Enterprise: Naval Supply Systems Command

    DTIC Science & Technology

    2011-12-01

    27 C. KAREN S. WHELAN-BERRY WITH KAREN A. SOMERVILLE , LINKING CHANGE DRIVERS AND THE ORGANIZATIONAL CHANGE PROCESS: A REVIEW AND SYNTHESIS...and Synthesis by Karen S. Whelan-Berry and Karen A. Somerville .42 Their model provides the basis for analysis to determine how organizations can... Somerville , “Linking Change Drivers and the Organizational Change Process: A Review and Synthesis,” Journal of Change Management, 10, 2 (2010): 175-193

  13. Nursing: Evidence-Based Practice Skills Nursing: Evidence-Based Practice Skills Karen Holland and Colin Rees Oxford University Press £21.99 320 pp 9780199563104 0199563101 [Formula: see text].

    PubMed

    2011-07-01

    STUDENTS, NEWLY qualified nurses and those undertaking post-registration studies will find this book a useful introduction to evidence-based practice. it is well written and simple to understand, and its authors have adopted a balanced approach to the subject.

  14. Health Visiting: Preparation for Practice (Fourth edition) Luker Karen McHugh Gretl and Bryar Rosamund Health Visiting: Preparation for Practice (Fourth edition) 312pp £32.99 Wiley Blackwell 9781119078586 111907858X [Formula: see text].

    PubMed

    2017-04-12

    Children, families and the communities they live in deserve high-quality care from well-informed health visitors and healthcare staff. Having an understanding of the role and responsibilities of health visitors and the wider influences on their practice has never been more important.

  15. Healing Arts Therapies and Person-Centred Dementia Care Healing Arts Therapies and Person-Centred Dementia Care Anthea Innes and Hatfield Karen (editors) Jessica Kingsley 137pp £13.95 1 84310 038X 184310038X.

    PubMed

    2002-06-01

    Reading this digestible good practice guide, one is struck by the sheer enthusiasm of the contributors both on paper and in the descriptions of their 'therapies'. The authors are absolutely committed to their own specialties, and desire that we are as persuaded as they by the psychotherapeutic impact of the healing arts in dementia care. This evangelism becomes a little wearing after a while and the case studies that flesh out the meaning of what is observed feel a little too neat. The book suffers a little for its American influences and expectations. One feels that all environments are assumed to have daily access to music/drama/art therapists.

  16. Retraction notice to "Ca. 2.5 billion year old mafic dykes in western Shandong Province: Implications for hybridization between subducted continental crust and the North China Craton, China"

    NASA Astrophysics Data System (ADS)

    Liu, Shen; Feng, Caixia; Zhai, Mingguo; Hu, Ruizhong; Gao, Shan; Lai, Shaocong; Zou, Haibo; Yan, Jun

    2015-02-01

    This article has been retracted: please see Elsevier Policy on Article Withdrawal. This article has been retracted at the request of the Editors-in-Chief. The article duplicates significant parts of a paper that had already appeared in, and was withdrawn from Precambrain Research (http://dx.doi.org/10.1016/j.precamres.2014.08.012") One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper is not under consideration for publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.

  17. A large scale investigation into changes in coal quality caused by dolerite dykes in Secunda, South Africa-implications for the use of proximate analysis on a working mine

    NASA Astrophysics Data System (ADS)

    Bussio, John P.; Roberts, James R.

    2016-05-01

    The coalfields of South Africa contain numerous dolerite intrusions, which affected the quality of the surrounding coal through thermal processes, commonly believed to be controlled by the size of the magmatic body. Data gathered from a working coalfield in Secunda, South Africa, suggest that the relationship between intrusive sills and coal is complex and factors other than intrusion width must be considered in relation to the contact metamorphic effect. The study area contains multiple dolerite intrusions of Karoo age, of which three intrusions occur as sills intruded close to the main coal seam of the. A large database (>8000 boreholes) of coal quality data was used to investigate the presence or absence of a change in coal quality relative to dolerite proximity. Reduction in coal quality was defined using three proximate analysis values, namely the ash, volatile content and dry ash free volatile (DAFV) as defined in the coal industry. The resultant investigation showed no correlation between the position and thickness of the dolerites, and changes in coal quality as measured by proximate analysis. In the absence of a linear relationship between coal quality and dolerite proximity, two processes are proposed to explain the absence of the contact metamorphic effects expected from previous studies. Firstly dolerite emplacement dynamics may influence the size of the metamorphic aureole produced by an intrusion, invalidating intrusion size as a measure of thermal output. Secondly, hydrothermal fluids mobilised by the dolerite intrusions, either from the country rock or the intrusion itself may percolate through the coal and act as the metamorphic agent responsible for changing coal quality, by dissolving the volatile and semi-volatile components of the coal and transporting them to other locations. These two processes are sufficient to explain the lack of a clear "metamorphic effect" related to the dolerite intrusions. However, the perceived lack of a clear correlation between the coal quality parameters and the metamorphic effects associated with dolerite intrusion may also reflect the inadequacies of proximate analysis techniques in quantifying geological processes within the coal.

  18. Evolution of deformation and stress changes during the caldera collapse and dyking at Bárdarbunga, 2014-2015: Implication for triggering of seismicity at nearby Tungnafellsjökull volcano

    NASA Astrophysics Data System (ADS)

    Parks, Michelle Maree; Heimisson, Elías Rafn; Sigmundsson, Freysteinn; Hooper, Andrew; Vogfjörd, Kristín S.; Árnadóttir, Thóra; Ófeigsson, Benedikt; Hreinsdóttir, Sigrún; Hjartardóttir, Ásta Rut; Einarsson, Páll; Gudmundsson, Magnús Tumi; Högnadóttir, Thórdis; Jónsdóttir, Kristín; Hensch, Martin; Bagnardi, Marco; Dumont, Stéphanie; Drouin, Vincent; Spaans, Karsten; Ólafsdóttir, Rósa

    2017-03-01

    Stress transfer associated with an earthquake, which may result in the seismic triggering of aftershocks (earthquake-earthquake interactions) and/or increased volcanic activity (earthquake-volcano interactions), is a well-documented phenomenon. However limited studies have been undertaken concerning volcanic triggering of activity at neighbouring volcanoes (volcano-volcano interactions). Here we present new deformation and stress modelling results utilising a wealth of diverse geodetic observations acquired during the 2014-2015 unrest and eruption within the Bárdarbunga volcanic system. These comprise a combination of InSAR, GPS, LiDAR, radar profiling and optical satellite measurements. We find a strong correlation between the locations of increased seismicity at nearby Tungnafellsjökull volcano and regions of increased tensile and Coulomb stress changes. Our results suggest that stress transfer during this major event has resulted in earthquake triggering at the neighbouring Tungnafellsjökull volcano by unclamping faults within the associated fissure swarm. This work has immediate application to volcano monitoring; to distinguish the difference between stress transfer and new intrusive activity.

  19. "SHRIMP geochronology for the 1450 Ma Lakhna dyke swarm: Its implication for the presence of Eoarchaean crust in the Bastar Craton and 1450-517 Ma depositional age for Purana basin (Khariar), Eastern Indian Peninsula": Comment

    NASA Astrophysics Data System (ADS)

    Basu, Abhijit; Bickford, M. E.

    2011-11-01

    As critical comments to the recent paper by Ratre et al. (2010, Journal of Asian Earth Sciences 39, 565-577) we cite U-Pb SHRIMP and CHIME ages of magmatic and detrital zircon and monazite from the Chhattisgarh and the Khariar basins in the Bastar craton to argue that these basins closed ca. 1000 Ma. We further argue that geochronologic data, geological evidence, and geological logic strongly indicate that sedimentation in the Khariar basin did not continue up to or beyond 517 Ma, as stated by Ratre et al. (op. cit).

  20. Data-Based Detection of Potential Terrorist Attacks: Statistical and Graphical Methods

    DTIC Science & Technology

    2010-06-01

    following categories: Beall, Jeffrey; Kafadar, Karen: "The Proportion of NUC Pre-56 Titles Represented in OCLC WorldCat," College & Research...Resources & Technical Services 48(2): 92–101 (April 2004). • Beall, Jeffrey; Kafadar, Karen: The Proportion of NUC Pre-56 Titles Represented in OCLC ...Kafadar, Karen: The Proportion of NUC Pre-56 Titles Represented in OCLC World- Cat, College & Research Libraries 66(5): 431–435 (2005). Beall

  1. 75 FR 34139 - Ocean Transportation Intermediary License Applicants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ... 90245, Officers: Peter Porse, President/Director (Qualifying Individual), Ken Koh, Vice President/Director, Application Type: New NVO License. Dated: June 11, 2010. Karen V. Gregory, Secretary....

  2. 75 FR 29545 - Ocean Transportation Intermediary License Applicants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-26

    .... Officers: Peter Moe, Jr., President, (Qualifying Individual). Barbara M. Moe, Secretary. Application Type.../ Treasurer, (Qualifying Individual). Application Type: New NVO License. Dated: May 21, 2010. Karen V....

  3. 75 FR 65485 - Sunshine Act Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-25

    ... Session 1. Staff Briefing on Reporting Requirement Options for Global Vessel Alliances. 2. Staff Briefing.... Staff Briefing Regarding China Maritime Regulatory Issues. Contact Person For More Information: Karen...

  4. 78 FR 41497 - Submission for OMB Review, Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-10

    ..., Departmental Offices, Office of Financial Stability, ATTN: Karen Chang, 1500 Pennsylvania Avenue NW... Chang, 1500 Pennsylvania Avenue NW., Washington, DC 20220. SUPPLEMENTARY INFORMATION: Title: Study...

  5. New Crewmates Welcomed Aboard Station

    NASA Video Gallery

    NASA astronaut Karen Nyberg, Russian Federal Space Agency cosmonaut Fyodor Yurchikhin and European Space Agency astronaut Luca Parmitano joined their Expedition 36 crewmates when the hatches betwee...

  6. 75 FR 21007 - Food Labeling; Public Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-22

    ... accommodation options, contact conference coordinators Karen Smith or Andrea Graves at FAPC, OSU, 148 FAPC... registration fee to cover the cost of facilities, materials, lunch, and breaks. Seats are limited; please... payable to FAPC. If you need special accommodations due to a disability, please contact Karen Smith...

  7. 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…

  8. Transforming Content Knowledge: Learning to Teach about Isotopes.

    ERIC Educational Resources Information Center

    Geddis, Arthur N.; And Others

    1993-01-01

    Presents a vignette about Karen, a student teacher in her first attempt at teaching chemical isotopes. Karen focuses on transmitting what she knows. An overview of Schulman's conceptions of pedagogical content knowledge is then provided. Shulman's ideas are employed to frame the experiences of Alan, a student teacher, as he and his cooperating…

  9. HIV/AIDS - Multiple Languages: MedlinePlus

    MedlinePlus

    ... this page, please enable JavaScript. Chinese - Traditional (繁體中文) French (français) Karen (Sgaw Karen) Korean (한국어) Nepali (नेपा ... PDF Substance Abuse and Mental Health Services Administration French (français) HIV/AIDS - CD4 Count English Taux de ...

  10. Coming Out of the Classroom Closet: Gay and Lesbian Students, Teachers and Curricula.

    ERIC Educational Resources Information Center

    Harbeck, Karen M., Ed.

    This book presents a collection of 10 research reports and essays on homosexuality and education. After an introduction by Karen M. Harbeck, chapters include: (1) "Addressing the Needs of Lesbian, Gay, and Bisexual Youth: The Origins of PROJECT 10 and School-Based Intervention" (Virginia Uribe and Karen M. Harbeck); (2) "Educators,…

  11. Precision Morphology in Sulfonic, Phosphonic, Boronic, and Carboxylic Acid Polyolefins

    DTIC Science & Technology

    2013-11-15

    S. Aitken, C. Francisco Buitrago , Jason D. Heffley, Minjae Lee, Harry W. Gibson, Karen I. Winey, Kenneth B. Wagener. Precision Ionomers: Synthesis...Seitz, C. Francisco Buitrago , Karen I. Winey, Kathleen L. Opper, Travis W. Baughman, Kenneth B. Wagener, Todd M. Alam. The impact of zinc

  12. Setting the Standard: Role Definition for a Secondary Literacy Coach

    ERIC Educational Resources Information Center

    DiMeglio, Rachele A.; Mangin, Melinda M.

    2010-01-01

    This case introduces Karen, a middle school literacy coach attempting to navigate the myriad tasks she performs. As she aims to satisfy everyone's needs Karen struggles to prioritize and focus her work. The accompanying teaching notes utilize the International Reading Association's "Standards for Middle and High School Literacy Coaches" to…

  13. Rethinking the REAL ID Act and National Identification Cards as a Counterterrorism Tool

    DTIC Science & Technology

    2009-12-01

    technology upgrade, replacing the geometry readers with a system that scans fingerprint information. According to Kim Prunty, a Walt Disney World spokesperson...expertise because Walt Disney Theme Parks are responsible for the 234 Karen Harmel, Walt Disney World : The...june99/scans21.htm (accessed May 21, 2009 ). Harmel, Karen, Walt Disney World : The Government’s Tomorrowland?, September 1, 2006, http

  14. The Political Dynamics of Insurgency: The Importance of Government Legitimacy

    DTIC Science & Technology

    2012-03-22

    ORGANIZATION REPORT NUMBER Professor Karen Aguilar Department of National Security and Strategy 9. SPONSORING...Professor Karen Aguilar Project Adviser This SRP is submitted in partial fulfillment of the requirements of the Master of Strategic...opened negotiations with Luis Taruc, the charismatic leader of the Huks.45 Unlike his predecessor, Quirino initially opted for a policy of leniency for

  15. Finding Their Way: Faith and Fortitude Lift Family of Five

    ERIC Educational Resources Information Center

    Caroff, Maria

    2007-01-01

    In this article, the author shares the experiences of Giorgi family. She describes how parents Karen and Daniel handle the magnitude of caring for their three children--Elijah, Angelina and Jonathan--with autism. Through faith and fortitude, both Karen and Daniel surmount the myriad of challenges of taking care of their autistic children. Both…

  16. Specifications for an Advanced Instructional Design Advisor (AIDA) for Computer-Based Training

    DTIC Science & Technology

    1991-05-01

    11. MAJ Karen Reid ATC/ TTIP 15. Dr. Robert Seidel Army Research Inst. 8 3.3 PROJECT MANAGEMENT The Project Manager for the contractor, Mei Associates...Training System CAPT James Coward HQ ATC/XPCRI MAJ Robert Mongillo ATC/XPC MAJ Karen Reid ATC/ TTIP Dr. Ok-choon Park Army Res. Institute Mei Associates Dr...Robert Mongillo ATC/XPC MAJ Karen Reid ATC/ TTIP Dr. Ok-choon Park Army Research Institute LCOL Larry Clemons ATC/XPCRI Dr. Dee Andrews AFHRL/OT Mr. John

  17. Deformation modelling of the 2014 Bárðarbunga rifting event in Iceland

    NASA Astrophysics Data System (ADS)

    Hooper, Andrew; Sigmundsson, Freysteinn; Hreinsdóttir, Sigrún; Heimisson, Elías; Ófeigsson, Benedikt; Dumont, Stéphanie; Parks, Michelle; Spaans, Karsten; Drouin, Vincent; Árnadóttir, Thóra; Vogfjörd, Kristín; Jónsdóttir, Kristín; Fridriksdóttir, Hildur; Hensch, Martin

    2015-04-01

    Between 16 August and 31 August 2014 a dike propagated from Bárðarbunga caldera, which culminated in an eruption at Holuhraun that is still ongoing at the time of writing. Previous models of other 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. Our modelling shows how the 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 propagation path is not simple, comprising many segments with differing orientations. We modelled the dyke propagation using deformation data from InSAR and GPS. Initial modelling of the dyke, with no a priori constraints on position, strike or dip, show the deformation data require the dyke to be approximately vertical and line up with the seismicity. We therefore fixed the dip to be vertical and the lateral position of the dyke to coincide with the earthquake locations. We modelled the dyke as a series of rectangular patches and estimated the opening and slip on each patch for each day between 16 August and 6 September. The results suggest that most of the magma injected into the dyke is shallower than the seismicity, which mostly spans the depth range from 5 to 8 km below sea level. Where constraints from InSAR and GPS are good, significant opening is all shallower than 5 km, and opening is up to 6 m. The total volume intruded into the dyke by 28 August was 0.48-0.51 km3. We also modelled the expected propagation direction of the dyke considering the regional stress field and the spatially-variable overburden. We find

  18. Biographies of Eminent Women in Psychology: Models for Achievement.

    ERIC Educational Resources Information Center

    Furumoto, Laurel; And Others

    1980-01-01

    In order to recognize women's contributions to the field of psychology, biographies of Margaret Floy Washburn, Mary Cover Jones, Karen Horney, Susan Grey, Edna Heidbreder, Ann Roe, and Mary Whitton Calkins are presented. (BEF)

  19. Expedition 36/37 Crew Preps for Launch

    NASA Video Gallery

    Soyuz Commander Fyodor Yurchikhin of the Russian Federal Space Agency, NASA astronaut Karen Nyberg and European Space Agency astronaut Luca Parmitano prepare for their May 28 Soyuz launch to join t...

  20. 76 FR 32956 - Gulf of Mexico Fishery Management Council; Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-07

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

  1. Designing a catheter skills training programme.

    PubMed

    Logan, Karen

    Karen Logan describes how a team of continence advisers designed and implemented a training programme that allows local nurses to meet the national occupational standards and competencies in catheterisation and catheter care.

  2. Expedition 36 Final Exams and Training

    NASA Video Gallery

    The Expedition 36 crew members conduct final training at the Gagarin Cosmonaut Training Center before their May 28 launch to the International Space Station. Flight Engineers Karen Nyberg, Fyodor Y...

  3. 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.

  4. Tuskegee Airmen Episode 4

    NASA Video Gallery

    Karen Ricks, DLN Coordinator at NASA Langley Research Center, conducts an interview with Tuskegee Airmen Lieut. Col. Terrence Spann, about his experiences with the Tuskegee Airmen along with the hi...

  5. Expedition 36/37 Crew Launch Preps in Kazakhstan

    NASA Video Gallery

    Soyuz Commander Fyodor Yurchikhin and Flight Engineers Karen Nyberg and Luca Parmitano arrive in Kazakhstan to prepare for their upcoming launch to the International Space Station. They are targete...

  6. 75 FR 32770 - Notice of Withdrawal of Pesticide Petitions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-09

    ...: samek.karen@epa.gov . 5. PP 9E7603 (Polymerized fatty acid copolymer esters with a minimum number... residues of the following polymerized fatty acid copolymer esters with a minimum number average...

  7. A potpourri of practical (or not) projectiles

    NASA Astrophysics Data System (ADS)

    Riendeau, Diane

    2010-11-01

    Special thanks to Frank Noschese, John Jay High School, and Karen Boone, Hallettsville High School. If you have a favorite video, please send the link and a brief description to: Diane Riendeau at driendeau@dist113.org.

  8. 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.

  9. 77 FR 13604 - Ocean Transportation Intermediary License; Applicants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-07

    ... 149 Court, Miami, FL 33194, Officer: Robert Esquivel, President/Secretary/Treasurer (Qualifying... Type: New NVO & OFF License. Dated: March 2, 2012. Karen V. Gregory, Secretary. BILLING CODE 6730-01-P...

  10. Updating Regional Supplements to the Corps of Engineers Wetland Delineation Manual

    DTIC Science & Technology

    2012-08-01

    Martel Corps California Paul Minkin Corps Massachusetts Karen Mulligan Corps Washington DC Chris Noble Corps Mississippi Norman Melvin NRCS Texas...Massachusetts Katherine Trott Corps Virginia Lenore Vasilas NRCS Washington DC POINTS OF CONTACT: For additional information, contact Mr. Jacob

  11. 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.

  12. FINDING THE SOMETHING IN NOTHING.

    PubMed

    Robbins, Michael

    2016-07-01

    Formless Infinity: Clinical Explorations of Matte Blanco and Bion. By Riccardo Lombardi. Translated by Karen Christenfeld, Gina Atkinson, Andrea Sabbadini, and Philip Slotkin. London/New York: Routledge, 2016. 282 pp.

  13. 78 FR 20095 - Proposed Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... Defense Standardization Program Office (DSPO), Defense Logistics Agency, J-307, Attention: Ms. Karen Bond... Standardization Program Office (DSPO) at (703) 767-6871. Title; Associated Form; and OMB Number:...

  14. Tuskegee Airmen Episode 3

    NASA Video Gallery

    Karen Ricks, DLN Coordinator at NASA Langley Research Center, conducts an interview with Tuskegee Airmen Cpl. Wilbert Gore Senior, about his experiences with the Tuskegee Airmen along with the hist...

  15. Tuskegee Airmen Episode 1

    NASA Video Gallery

    Karen Ricks, DLN Coordinator at NASA Langley Research Center, conducts an interview with Tuskegee Airmen Chief Master Sgt. Grant Williams Senior, about his experiences with the Tuskegee Airmen alon...

  16. 78 FR 77646 - Proposed Information Collection; Comment Request; Current Population Survey (CPS) Basic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-24

    ... Woods, U.S. Census Bureau, 7H110F, Washington, DC 20133-8400 at (301) 763-3806 (or via the internet at Karen.g.wms.woods@census.gov ). SUPPLEMENTARY INFORMATION: I. Abstract The Census Bureau plans...

  17. 77 FR 32977 - Announcement of Funding Awards for Fiscal Year 2012 Transformation Initiative: Choice...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-04

    ... Investigator: Matthew Gebhardt. Grant: $76,948. 3. University of California--Berkeley (UC). Address: 2150 Shattuck Avenue, Suite 300, Berkeley, CA 94794-5940. Co-Principal Investigators: Karen Chapple,...

  18. 77 FR 6112 - Notice of Final National Pollutant Discharge Elimination System (NPDES) General Permit for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-07

    ...'') and that are subject to 40 CFR part 412, Subparts A (Horses and Sheep), C (Dairy Cows and Cattle Other... Feeders, LLC; Tri-State Feeders, Inc.; Dairy Producers of New Mexico (DPNM); Karen Brewer;...

  19. Tuskegee Airmen Episode 2

    NASA Video Gallery

    Karen Ricks, DLN Coordinator at NASA Langley Research Center, conducts an interview with Tuskegee Airmen Sgt. Harry Quinton, about his experiences with the Tuskegee Airmen along with the history of...

  20. 78 FR 52505 - Manufacturing Extension Partnership Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-23

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board AGENCY... National Institute of Standards and Technology (NIST) announces that the Manufacturing Extension... FURTHER INFORMATION CONTACT: Karen Lellock, Manufacturing Extension Partnership, National Institute...

  1. 75 FR 19941 - Manufacturing Extension Partnership Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-16

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board AGENCY... announces that the Manufacturing Extension Partnership (MEP) Advisory Board, National Institute of Standards..., 2010. FOR FURTHER INFORMATION CONTACT: Karen Lellock, Manufacturing Extension Partnership,...

  2. 75 FR 50749 - Manufacturing Extension Partnership Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-17

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board AGENCY... announces that the Manufacturing Extension Partnership (MEP) Advisory Board, National Institute of Standards... INFORMATION CONTACT: Karen Lellock, Manufacturing Extension Partnership, National Institute of Standards...

  3. 76 FR 53666 - Manufacturing Extension Partnership Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-29

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board AGENCY... National Institute of Standards and Technology (NIST) announces that the Manufacturing Extension...: Karen Lellock, Manufacturing Extension Partnership, National Institute of Standards and Technology,...

  4. 77 FR 20790 - Manufacturing Extension Partnership Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-06

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board AGENCY... announces that the Manufacturing Extension Partnership (MEP) Advisory Board, National Institute of Standards... INFORMATION section below. FOR FURTHER INFORMATION CONTACT: Karen Lellock, Manufacturing Extension...

  5. 78 FR 32240 - Manufacturing Extension Partnership Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-29

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board AGENCY... National Institute of Standards and Technology (NIST) announces that the Manufacturing Extension... SUPPLEMENTARY INFORMATION section of this notice. FOR FURTHER INFORMATION CONTACT: Karen Lellock,...

  6. 76 FR 22674 - Manufacturing Extension Partnership Advisory Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-22

    ... National Institute of Standards and Technology Manufacturing Extension Partnership Advisory Board AGENCY... announces that the Manufacturing Extension Partnership (MEP) Advisory Board, National Institute of Standards... than May 2, 2011. FOR FURTHER INFORMATION CONTACT: Karen Lellock, Manufacturing Extension...

  7. 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…

  8. Ebola (Ebola Virus Disease): Q&As on Transmission

    MedlinePlus

    ... Other African Countries Partnering with West African Communities Call CDC's Role Photos From the Field CDC Responder Stories Allison Friedman Gary Cobb, Arthur Hudson, and Drenda Morrissette John Saindon and Brian Bird Karen Wong Angela Dunn Brant Goode CDC In ...

  9. 76 FR 63618 - Notice of Agreements Filed

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ... Singapore. Agreement No.: 012138. Title: CSAV/CCNI Venezuela Space Charter Agreement. Parties: Compana Sud... Venezuela. Dated: October 7, 2011. By Order of the Federal Maritime Commission. Karen V. Gregory,...

  10. 75 FR 44794 - Rendezvous International v.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-29

    ... From the Federal Register Online via the Government Publishing Office FEDERAL MARITIME COMMISSION Rendezvous International v. Chief Cargo Services, Inc., Kaiser Apparel, Inc., Edco Logistics, Inc., Oriental.... Karen V. Gregory, Secretary. BILLING CODE P...

  11. 76 FR 73654 - The Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-29

    ... appointments of, Estelle B. Richman, Karen Newton Cole, Peter J. Grace, Jemine A. Bryon, Clifford D. Taffett, Bryan Greene, Kevin M. Simpson, Lori Michalski, Donald J. LaVoy, Patricia A. Hoban-Moore, and Kevin...

  12. 78 FR 49317 - North Carolina Disaster # NC-00054

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... 76155. FOR FURTHER INFORMATION CONTACT: Alan Escobar, Office of Disaster Assistance, U.S. Small Business... Assistance Numbers 59002 and 59008) Dated: August 6, 2013. Karen G. Mills, Administrator. BILLING CODE...

  13. 78 FR 42148 - North Carolina Disaster #NC-00052

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-15

    ... INFORMATION CONTACT: Alan Escobar, Office of Disaster Assistance, U.S. Small Business Administration, 409 3rd... 59002 and 59008) Dated: July 9, 2013. Karen G. Mills, Administrator. BILLING CODE 8025-01-P...

  14. Expedition 36 Crew Launches on Fast Track to Station

    NASA Video Gallery

    The Soyuz TMA-09M spacecraft carrying Soyuz Commander Fyodor Yurchikhin and Flight Engineers Karen Nyberg and Luca Parmitano launches from the Baikonur Cosmodrome in Kazakhstan to begin an expedite...

  15. Friends of the National Library of Medicine 2012 Annual Awards Gala | NIH MedlinePlus the Magazine

    MedlinePlus

    ... MD, MHS, Professor, Johns Hopkins Bloomberg School of Public Health Distinguished Health Communications Award: Karen Hunter, Senior Vice President Global Academic & Customer Relations, Elsevier Michael DeBakey Library Services Outreach Award: Anna ...

  16. 75 FR 38549 - Notice of Appointment of Individuals To Serve as Members of Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-02

    ...Filippo. Member--Robert B. Koopman. Member--Karen Laney. Member--Lynn I. Levine. Member--James M. Lyons. Member--Stephen A. McLaughlin. Member--Lyn M. Schlitt. This notice is published in the Federal...

  17. 78 FR 64535 - Notice of Appointment of Individuals To Serve as Members of Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ... Member--Catherine DeFilippo Member-- William E. Dobryzkowski Member --Robert B. Koopman Member--Karen Laney Member--Andrew Martin Member--Margaret D. MacDonald Member--Stephen A. McLaughlin Member--Lyn...

  18. 78 FR 13706 - Notice of Appointment of Individuals To Serve as Members of Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-28

    ... Dean A. Pinkert Member--Catherine DeFilippo Member--Robert B. Koopman Member--Karen Laney Member--Bill Dobryzkowski Member--Andrew Martin Member--Stephen A. McLaughlin Member--Lyn M Schlitt FOR FURTHER...

  19. 75 FR 70289 - Notice of Appointment of Individuals to Serve as Members of Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ...Filippo Member: Robert B. Koopman Member: Karen Laney Member: Lynn I. Levine Member: James M. Lyons Member: Stephen A. McLaughlin Member: Lyn M. Schlitt Member: Andrew Martin This notice is published in the...

  20. An Implementation Guide for Settling Contract Disputes Within DoD Using Alternative Disputes Resolution Methods

    DTIC Science & Technology

    1989-12-01

    WITHIN DOD USING ALTERNATIVE DISPUTES RESOLUTION METHODS by Karen K. Day December 1989 Thesis Advisor: E. Neil Hart Approved for public release...DTIC USERS Unclassified 22a NAME OF RESPONSIBLE INDIVIDUAL 22b TELEPHONE (Include Area Code) 2c OFICE . . Neil Hart . (408)646-2775 1 54 DOForm 1473...oiai NAVAL POSTGRADUATE SCHOOL * December 1989 o, Author: ~~( Karen K. Day Approved by: S7 7 x-’ E. Neil Hart, Thesis Advisor Nancy C. Roberts

  1. Living with HIV/AIDS - Multiple Languages: MedlinePlus

    MedlinePlus

    ... gov/languages/livingwithhivaids.html Other topics A-Z A B C D E F G H I J K L M N O P Q R S T U V W XYZ List of All Topics All Living with HIV/AIDS - Multiple Languages To use the sharing features on this page, please enable JavaScript. French (français) Karen (Sgaw Karen) Nepali (नेपाली) Somali ( ...

  2. HIV/AIDS and Infections - Multiple Languages: MedlinePlus

    MedlinePlus

    ... gov/languages/hivaidsandinfections.html Other topics A-Z A B C D E F G H I J K L M N O P Q R S T U V W XYZ List of All Topics All HIV/AIDS and Infections - Multiple Languages To use the sharing features on this page, please enable JavaScript. French (français) Karen (Sgaw Karen) Nepali (नेपाली) Somali ( ...

  3. HIV/AIDS and Pregnancy - Multiple Languages: MedlinePlus

    MedlinePlus

    ... gov/languages/hivaidsandpregnancy.html Other topics A-Z A B C D E F G H I J K L M N O P Q R S T U V W XYZ List of All Topics All HIV/AIDS and Pregnancy - Multiple Languages To use the sharing features on this page, please enable JavaScript. French (français) Karen (Sgaw Karen) Nepali (नेपाली) Somali ( ...

  4. Bibliography of In-House and Contract Reports. Supplement 15.

    DTIC Science & Technology

    1988-04-01

    15 Annemarie Black E. James Books Karen Carroll April 1988 U- D" LECTE APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED. U.S. ARMY CORPS OF...Security Classification) Bibliography of In-House and Contract Reports, Supplement 15 12. PERSONAL AUTHOR(S) Annemarie Black, E. James Books and Karen...this report. 13 ETL-0433 AD-A171 561 A PROGRAMMING ENVIRONMENT FOR PARALLEL VISION ALGORITHMS August 1986 0 Brown , Christopher University of Rochester

  5. 77 FR 64331 - City of Burlington, IA; FFP Iowa 5, LLC; Notice of Competing Preliminary Permit Applications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-19

    ... gates and 3 roller gates; (2) a 2,200-foot-long submersible earth dyke; and (3) an approximately 12,000... existing submersible dyke; (3) a 1-mile- long, 12.5-kilovolt (kV) transmission line; and (4)...

  6. 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.

  7. Two Cenozoic tectonic events of N-S and E-W extension in the Lhasa Terrane: Evidence from geology and geochronology

    NASA Astrophysics Data System (ADS)

    Huang, Feng; Xu, Ji-Feng; Chen, Jian-Lin; Wu, Jian-Bin; Zeng, Yun-Chuan; Xiong, Qiu-Wei; Chen, Xue-Feng; Yu, Hong-Xia

    2016-02-01

    Cenozoic active structures in the Tibetan Plateau are mainly regional N-S trending extensional faults and grabens, and E-W trending extensional tracks that are related to the transition from syn- to post-collision between India and Asia. E-W trending tracks are parallel to the direction of Neo-Tethyan oceanic convergence and consist of extensional volcanic-sedimentary basins and magmatic dykes in the southern Lhasa Terrane, Tibet. N-S trending tracks comprise faults and grabens, which are widely developed in Tibet. It remains unknown how and when the geodynamic transition from E-W to N-S trending tectonic tracks occurred. This study describes both E-W and N-S trending tectonic tracks identified at Dazi area of southern Lhasa Terrane, where E-W trending mafic dykes intruded a granitoid and late-stage N-S trending felsic dykes cut across E-W trending mafic dykes. Zircons from four granitoid samples yield consistent crystallization ages of ca. 60 Ma and positive εHf(t) values (~+ 9). An altered dioritic vein, which cuts the mafic dykes, yields an age of ca. 53 Ma. These new dating results indicate that E-W trending dykes, which formed due to regional N-S extension, were emplaced between 60 and 53 Ma. In addition, two N-S trending monzonitic porphyritic dykes, which cut the mafic dykes, yield U-Pb zircon ages of ca. 17 Ma with moderate positive εHf(t) values (+ 3 to + 9.6), as well as a NNE-SSW trending quartz monzonitic dyke, which cuts all other types of dykes, yields U-Pb ages of ca. 13 Ma. This suggests that E-W extension took place between 17 and 13 Ma. These results, in combination with existing age data for Gangdese granitoids and mafic magmatism, indicate the occurrence of two major extensional events at 60-53 Ma and 17-13 Ma. In turn, this implies that the transition from E-W to N-S trending tectonic and the onset of E-W extension occurred at ca. 17 Ma or slightly earlier. Paleocene granitoids have geochemical characteristics that are indicative of both

  8. #WomenInSTEM: Identifying an Opportunity for Change

    SciTech Connect

    Lefkowitz, Karen

    2014-10-20

    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.

  9. #WomenInSTEM: Identifying an Opportunity for Change

    ScienceCinema

    Lefkowitz, Karen

    2016-07-12

    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.

  10. Libraries in Kansas: MedlinePlus

    MedlinePlus

    ... 240-7973 http://iach.amedd.army.mil Garden City St. Catherine Hospital Medical Library 401 East Spruce ... City, KS 67846-5679 620-272-2172 Kansas City University of Kansas Medical Center Archie R. Dykes ...

  11. An integrated model of kimberlite ascent and eruption.

    PubMed

    Wilson, Lionel; Head Iii, James W

    2007-05-03

    Diatremes are carrot-shaped bodies forming the upper parts of very deep magmatic intrusions of kimberlite rock. These unusual, enigmatic and complex features are famous as the source of diamonds. Here we present a new model of kimberlite ascent and eruption, emphasizing the extremely unsteady nature of this process to resolve many of the seemingly contradictory characteristics of kimberlites and diatremes. Dyke initiation in a deep CO2-rich source region in the mantle leads to rapid propagation of the dyke tip, below which CO2 fluid collects, with a zone of magmatic foam beneath. When the tip breaks the surface of the ground, gas release causes a depressurization wave to travel into the magma. This wave implodes the dyke walls, fragments the magma, and creates a 'ringing' fluidization wave. Together, these processes form the diatreme. Catastrophic magma chilling seals the dyke. No precursor to the eruption is felt at the surface and the processes are complete in about an hour.

  12. Sinus Rinsing and Neti Pots

    MedlinePlus

    ... D, Van Dyke R, Stern H, Xiao L, Beach MJ. The first association of a primary amebic ... B, Kahler AM, Schneeberger C, da Silva AJ, Beach MJ. Deaths from Naegleria fowleri associated with sinus ...

  13. 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

  14. 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

  15. 78 FR 39828 - Proposed Collection; Comment Request for Forms 8857 and 8857(SP)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-02

    ... Service, Room 6129, 1111 Constitution Avenue NW., Washington, DC 20224. FOR FURTHER INFORMATION CONTACT... Dyke at Internal Revenue Service, room 6129, 1111 Constitution Avenue NW., Washington, DC 20224, or...

  16. 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.

  17. 2D dynamical magma propagation modeling: application to the 2001 Mount Etna eruption

    NASA Astrophysics Data System (ADS)

    Pinel, Virginie; Carrara, Alexandre; Maccaferri, Francesco; Rivalta, Eleonora; Corbi, Fabio

    2016-04-01

    Numerical and analog studies of dike propagation in a stress field induced by volcanic edifice construction have shown that surface loading tends both to attract the magma and to reduce its velocity. Available numerical models can either calculate the trajectory or the velocity of the ascending dikes, but not both of them simultaneously. We developed a hybrid model of dyke propagation in two dimensions solving both for the magma trajectory and velocity as a function of the source overpressure, the magma physical properties (density and viscosity) as well as the crustal density and stress field. We first calculate a dyke trajectory in 2D and secondly run a 1D dynamical model of dyke propagation along this trajectory taken into account the influence of the stress field seen by the magma along this path. This model is used to characterize the influence of surface load on magma migration towards the surface and compared to previous results obtained by analog modeling.We find that the amplitude of dyke deflection and magma velocity variation depend on the ratio between the dyke driving pressure (source overpressure as well buoyancy) and the stress field perturbation. Our model is then applied to the July 2001 eruption of Etna, where the final dyke deflection had been previously interpreted as due to the topographic load by Bonaccorso et al. [2010]. We show that the velocity decrease observed during the last stage of the propagation can also be attributed to the local stress field. We use the dyke propagation duration to estimate the magma overpressure at the dyke bottom to be less than 4 MPa.

  18. The Determination of Navy Family Housing Requirements

    DTIC Science & Technology

    1992-04-01

    AD-A253 487 The Determination of Navy Family Housing Requirements NA10IR1 DTIC D:~TI Eric M. Small UL E0 19925 L" Karen M. Dahut ODV fVP, gp20380...identification code (UIC), used to identify each operational unit. UICs for Navy (and Marine Corps) units are assigned by CNO; dummy UICs are assigned to non...w8226l///l//l lll/!/l/ l April 1992 The Determination of Navy Family Housing Requirements NA1OIRI Eric M. Small Karen M. Dahut Prepared pursuant to

  19. Performance Oriented Packaging Testing of Tank, Cartridge, 3 in/50, Mk 5 Mods 0, 1, 2 for Packing Group II Solid Hazardous Materials

    DTIC Science & Technology

    1993-01-01

    Mods 0 , 1, 2 for Packing Group II Solid Hazardous Materials 6. AUTHORIS) Karen McDonnell 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8...design, size, and weight, this test is considered representative of qualifica- tion testing for the Mk 5 Mods 0 , 2 3"/50 Cartridge Tanks as per the...PERFORMANCE ORIENTED PACKAGING TESTING OF TANK, CARTRIDGE, 3"/50, MK 5 MODS 0 , 1, 2 FOR PACKING GROUP II SOLID HAZARDOUS MATERIALS Author: Karen

  20. Remote Sensing of Body Signs and Signatures

    DTIC Science & Technology

    1985-10-01

    REMOTE SENSING OF BODY SIGNS AND SIGNATURES LPrepared For Naval Medical Research and Development Command National Naval Medical Center, Bethesda...BODY SIGNS AND SIGNATURES S~By James C. Lin and Karen H. Chan Department of Bioengineering University of Illinois at Chicago Chicago, IL 60680 Abstract...Filters Di-t lb io. I AN!ý,z.biiity Codes I’ A.IDist jor p REMOTE SENSING OF BODY SIGNS AND SIGNATURES By James C. Lin and Karen H. Chan Department

  1. The sub-volcanic system of El Hierro, Canary Islands

    NASA Astrophysics Data System (ADS)

    Galindo, I.; Becerril, L.; Gudmundsson, A.

    2012-04-01

    The main volcanotectonic structures of El Hierro are three rift zones, trending northeast, west, and south. Most of the eruptions in El Hierro within these zones are basaltic fissure eruptions fed by subvertical dykes. The dykes appear as close to collinear or slightly offset segments, their surface expressions being clusters of cinder cones and eruptive vents. Three large landslides, referred to as El Golfo, El Julan, and Las Playas, have eroded the areas between rift axes and provide exposures that make it possible to provide a three-dimensional view of the uppermost part of the sub-volcanic system. Here we report the results of a structural study of the sub-volcanic system as obtained through the analysis of dykes and eruptive vents. The data obtained from surface outcrops have been combined with data from subsurface water galleries. More than 600 eruptive vents and 625 dykes have been studied in detail to characterise the subvolcanic system of the island. Using cinder-cone and other eruptive-vent alignments it has been possible to infer 115 eruptive fissures with lengths that range from 40 m to 2200 m. NE-SW trending volcanic fissures and dykes are common on the entire island and predominate in the northeast rift zone. The main strike of the dykes and fissures in the south and west rift zones are approximately NNW-SSE and E-W, respectively. However, in the west rift zone, eruptive fissures display a fan distribution with directions that range from N43°E to N124°E. Volcanic fissures within the El Golfo landslide valley trend parallel to the head scarp, except those that are close to the head of the valley, many of which are perpendicular to the scarp. Dykes show a radial distribution in the head scarp of the El Golfo landslide. Three feeder-dykes directly connected with their lava flows have been identified in El Hierro. Feeder dykes are difficult to observe in the field but provide important information when their lengths and thicknesses can be measured

  2. 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

  3. The Location of Error: Reflections on a Research Project

    ERIC Educational Resources Information Center

    Cook, Devan

    2010-01-01

    Andrea Lunsford and Karen Lunsford conclude "Mistakes Are a Fact of Life: A National Comparative Study," a discussion of their research project exploring patterns of formal grammar and usage error in first-year writing, with an invitation to "conduct a local version of this study." The author was eager to accept their invitation; learning and…

  4. "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…

  5. 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…

  6. 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…

  7. The Teacher-Student Writing Conference Reimaged: "Entangled Becoming-Writingconferencing"

    ERIC Educational Resources Information Center

    Phillips, Donna Kalmbach; Larson, Mindy Legard

    2013-01-01

    This analysis is experimental: we attempt to read data "with" the work of Karen Barad and in doing so "see" teacher-student writing conferences (a common pedagogy of US elementary school writing) as "intra-activity." Data were gathered during teacher-student writing conferences in a grade five US classroom over a…

  8. 77 FR 13123 - Cross-Media Electronic Reporting: Authorized Program Revision Approval, State of Ohio

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-05

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Cross-Media Electronic Reporting: Authorized Program Revision Approval, State of Ohio AGENCY..., seeh.karen@epa.gov . SUPPLEMENTARY INFORMATION: On October 13, 2005, the final Cross-Media...

  9. 76 FR 46798 - Cross-Media Electronic Reporting: Authorized Program Revision Approvals, Commonwealth of Kentucky

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-03

    ... From the Federal Register Online via the Government Publishing Office ENVIRONMENTAL PROTECTION AGENCY Cross-Media Electronic Reporting: Authorized Program Revision Approvals, Commonwealth of Kentucky..., seeh.karen@epa.gov . SUPPLEMENTARY INFORMATION: On October 13, 2005, the final Cross-Media...

  10. What Then Are We to Say about These Things?

    ERIC Educational Resources Information Center

    Japinga, Jeffrey; DeMoor, Robert

    2003-01-01

    In this article, the authors discuss Karen Cross's critique on LiFE (Living in Faith Everyday) curriculum. Cross's critique focuses on the following issues: (1) racism; (2) sexism; (3) classism; (4) suburbanism; (5) Reformed theology; and (6) method. To respond to Cross's critique is an invitation for everyone to examine not only one particular…

  11. 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…

  12. 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…

  13. 77 FR 59404 - Food Defense; Public Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-27

    ... it relates to food facilities such as farms, manufacturers, processors, distributors, retailers, and....hhs.gov . For information on accommodations: Karen Smith or Andrea Graves at the Robert M. Kerr Food... register by October 31, 2012. The workshop has a registration fee to cover the cost of...

  14. 75 FR 65390 - Connecticut Disaster #CT-00016

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-22

    .../18/2010. Incident: Severe storm and tornado. Incident Period: 06/24/2010. Effective Date: 10/18/2010...: 07/18/2011. ADDRESSES: Submit completed loan applications to: U.S. Small Business Administration... Assistance Numbers 59002 and 59008) Dated: October 18, 2010. Karen G. Mills, Administrator. BILLING CODE...

  15. 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);…

  16. 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…

  17. 76 FR 51039 - Statement of Organizations, Functions, and Delegations of Authority

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-17

    ... HUMAN SERVICES Food and Drug Administration Statement of Organizations, Functions, and Delegations of Authority AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug... INFORMATION CONTACT: Karen Koenick, Center for Drug Evaluation and Research (HFD-063), Food and...

  18. 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);…

  19. Bringing Technology to the Issues. Proceedings of the North East Association for Institutional Research Conference (16th, Pittsburgh, Pennsylvania, October 21-24, 1989).

    ERIC Educational Resources Information Center

    1989

    The conference program and the texts of 24 papers presented at the conference are provided in this document. Selected papers include: "The Use of the College Student Experience Questionnaire in Policy and Program Development" (Karen Bauer and Dale Trusheim); "Predicting Freshman Performance as Admissions Criteria" (David Zubrow); "Has the Middle…

  20. 75 FR 13318 - Virginia Electric and Power Company; Surry Power Station, Unit Nos. 1 and 2 (Surry 1 and 2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-19

    ... implementation date for Surry Unit 2. FOR FURTHER INFORMATION CONTACT: Karen Cotton, Office of Nuclear Reactor..., Division of Operating Licensing, Office of Nuclear Reactor Regulation. BILLING CODE 7590-01-P ... From the Federal Register Online via the Government Publishing Office NUCLEAR...

  1. A Comparison of Nurse Staffing Methods Used by the United States Air Force and Selected Civilian Hospitals

    DTIC Science & Technology

    1989-09-01

    34Nursng Marnagemert. 3: 27-42 iVarco19- ’ 24. Hart, Karen ano Karon oirou’uis!. Von~ tnni: a 5 :! e n-,Q: the Shor tage," Am~cqqn ourna, cf Nursing, 9...August 19 S. 35 49. University of Illinois Hospitai. Position Control Summary Report. I June 1989. 50. Vai I, James D. and others. "Worktoao

  2. 76 FR 51368 - SES Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-18

    ... Performance Review Board AGENCY: Federal Trade Commission. ACTION: Notice. SUMMARY: Notice is hereby given of the appointment of members to the FTC Performance Review Board. FOR FURTHER INFORMATION CONTACT: Karen.... SUPPLEMENTARY INFORMATION: Publication of the Performance Review ] Board (PRB) membership is required by 5...

  3. 75 FR 60125 - SES Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-29

    ... Performance Review Board AGENCY: Federal Trade Commission. ACTION: Notice. SUMMARY: Notice is hereby given of the appointment of members to the FTC Performance Review Board. FOR FURTHER INFORMATION CONTACT: Karen.... ] SUPPLEMENTARY INFORMATION: Publication of the Performance Review Board (PRB) membership is required by 5...

  4. 77 FR 33460 - SES Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-06

    ... Performance Review Board AGENCY: Federal Trade Commission. ACTION: Notice. SUMMARY: Notice is hereby given of the appointment of members to the FTC Performance Review Board. FOR FURTHER INFORMATION CONTACT: Karen.... SUPPLEMENTARY INFORMATION: Publication of the Performance Review Board (PRB) membership is required by 5...

  5. 75 FR 68375 - Performance Review Board Appointments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-05

    .... Arroyo, Bryan Ashe, Daniel M. Baker, Karen D. Bean, Michael J. Beck, Richard T. Birdwell, Stephanie E..., Michael R. Sobeck, Eileen Sonderman, Debra E. Stevenson, Katherine H. Stith, E. Melodee Taylor, Ione L. Taylor, Willie R. Thomas, Pilar M. Thorsen, Kimberley A. Triebsch, George F. Tsosie, Paul H. Tubbs,...

  6. Strong Female Characters in Recent Children's Literature.

    ERIC Educational Resources Information Center

    Heine, Pat; Inkster, Christine; Kazemek, Frank; Williams, Sandra; Raschke, Sylvia; Stevens, Della

    1999-01-01

    Shares the authors' criteria for evaluating female characters as positive role models in children's literature. Explores the criteria by examining "The Ballad of Lucy Wipple" (Karen Cushman). Discusses other recently published picture books and novels which feature strong females in history, in contemporary times, and in fantasy. (SR)

  7. 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…

  8. Out of Africa

    ERIC Educational Resources Information Center

    Wilbert, Nancy Corrigan

    2009-01-01

    Karen Blixen (Isak Dinesen), author of "Out of Africa," said, "God made the world round so people would never be able to see too far down the road." The author embraced this wonderful thought by venturing on a three-week journey to Kenya and Tanzania in search of grand adventure. In this article, the author shares her adventure…

  9. DEVELOP students attend conference

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Last month, Madeline Brozen and Jason Jones of the DEVELOP Program at John C. Stennis Space Center joined members from the program's national office at Langley Research Center to attend the Southern Growth Policies Board annual conference in Biloxi. Pictured are (l to r): Karen Allsbrook, Jonathan Gleason, Gov. Haley Barbour, Madeline Brozen, Lindsay Rogers and Tracey Silcox.

  10. Cognitive Science.

    ERIC Educational Resources Information Center

    Soni, P. Sarita, Ed.; Carmichael, Ann G., Ed.

    1993-01-01

    This theme issue features five articles profiling Indiana University faculty whose work on various campuses continues to broaden and advance knowledge about cognitive science. The articles in the journal are: "A Matter of Time" (Karen Grooms) which discusses the work of Robert F. Port; "Perceiving as a Complex System" (Tom…

  11. Astronaut Terry J. Hart in training session RMS for STS-2 bldg 29

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Astronaut Terry J. Hart in training session with the Remote Manipulator System (RMS) for STS-2 bldg 29. Views show Truly working at the command console while watching out the windows. Karen Ehlers, an RMS procedures specialist, can be seen at left side of frame while Astronaut Sally Ride waits on right for her time at the RMS.

  12. Hiring the Next Generation of Faculty. New Directions for Community Colleges, Number 152

    ERIC Educational Resources Information Center

    Cejda, Brent D., Ed.; Murray, John P., Ed.

    2011-01-01

    This volume contains the following papers: (1) Preparing to Hire the Best in the Perfect Storm (John P. Murray); (2) New Faculty Issues: Fitting In and Figuring It Out (Pamela L. Eddy); (3) An Approach to a Faculty Professional Development Seminar (Mary Bendickson and Karen Griffin); (4) Faculty Issues in Rural Community Colleges (Brent D. Cejda);…

  13. The Complex World of Adolescent Literacy: Myths, Motivations, and Mysteries

    ERIC Educational Resources Information Center

    Moje, Elizabeth Birr; Overby, Melanie; Tysvaer, Nicole; Morris, Karen

    2008-01-01

    In this article, Elizabeth Birr Moje, Melanie Overby, Nicole Tysvaer, and Karen Morris challenge some of the prevailing myths about adolescents and their choices related to reading. The reading practices of youth from one urban community are examined using mixed methods in an effort to define what, how often, and why adolescents choose to read. By…

  14. 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.…

  15. 76 FR 37055 - Notice of Request for Extension of Approval of an Information Collection; Importation of Baby...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... Collection; Importation of Baby Squash and Baby Courgettes From Zambia AGENCY: Animal and Plant Health... collection associated with regulations for the importation of baby squash and baby courgettes from Zambia... from Zambia, contact Ms. Karen Bedigian, Senior Export Specialist, Phytosanitary Issues Management,...

  16. 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)…

  17. 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…

  18. 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…

  19. Collaborative Learning.

    ERIC Educational Resources Information Center

    Levy-Reiner, Sherry, Ed.

    1985-01-01

    Descriptions of 10 college programs involving collaborative learning are presented, along with Karen T. Romer's essay, "Collaboration: New Forms of Learning, New Ways of Thinking." The essay identifies various kinds of collaborative learning as well as the benefits of collaborative models. The following programs and schools are…

  20. 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…

  1. 77 FR 23202 - Non-Vessel-Operating Common Carrier Service Arrangements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-18

    .... Capitol Street NW., Washington, DC 20573- 0001, Phone: (202) 523-5725, Fax: (202) 523-0014, Email... shipments of household goods belonging to military personnel from U.S. military bases in the Philippines to.... Gregory, at the telephone number or email provided above. By the Commission. Karen V. Gregory,...

  2. Foundation of the American Academy of Ophthalmology

    MedlinePlus

    ... org Business hours: 8 a.m. to 5 p.m., Pacific Time Tina McGovern, Executive Director tmcgovern@aao.org Corporate Support, Naming Opportunities and Planned Giving: Todd Lyckberg at tlyckberg@aao.org Individual Donations and Orbital Gala: Karen Duke at kduke@aao.org Log ...

  3. Energy Emergency Districts: Concepts and Applications.

    DTIC Science & Technology

    1985-06-01

    Los Angeles, CA Vice President, Power Supply San Diego Gas & Electric Company * Anita S. Garcia San Diego, CA Public Information Officer California...Volunteer Assistants Ladd Bogdonoff Karen Wilhelm Buckley Elizabeth Abad Michael Collins Florence Beller Louisa Finn Sharon Carrion Paul A. Grabhorn

  4. 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…

  5. 75 FR 8187 - Qualification of Drivers; Exemption Renewals; Vision

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    .... Murray, Anthony D. Ovitt, John R. Parsons, III, Martin Postma, Steven S. Reinsvold, Michael J. Richard, Glenn T. Riley, George E. Todd, Gary S. Warren and Bradley A. Weiser. In accordance with 49 U.S.C. 31136.... Cozat, Alex G. Dlugolenski, Karen Y. Duvall, Nigel L. Farmer, Gordon R. Fritz, John A. Graham, Jimmy...

  6. Post-Activity Report: DHSS Organisational Culture and Performance Workshop 2012

    DTIC Science & Technology

    2013-08-01

    summarises the outcomes of the workshop hosted by the DSTO Army Learning Organisation (ALO) team. Professor Karen Watkins (University of Georgia) facilitated...the workshop (applying Action Learning principles) to generate critical reflection and questioning of Defence organisational culture. The workshop...Culture and Performance Workshop Executive Summary The Defence Science and Technology Organisation (DSTO) Army Learning Organisation (ALO

  7. Lessons from Americas Top Teachers

    ERIC Educational Resources Information Center

    Instructor, 2005

    2005-01-01

    The winners of the 2005 State Teachers of the Year recently talked about their views on closing the achievement gap, the state of the profession, and what "really" works in the classroom. This article presents the views of these teachers namely Heidi Louise Capraro, Stanley Murphy, Vicki Lynn Goldsmith, Karen Heath, Kimberly Babeu, Jason Kampras,…

  8. Culture, Context, and Innovation: A Kiwi Canuck Perspective

    ERIC Educational Resources Information Center

    Marshall, Dave; Shaver, Karen

    2010-01-01

    This commentary lends a global practitioner perspective on the utility of this volume to the efforts of mentors and mentees and mentoring program developers. Dave Marshall and Karen Shaver, of Big Brothers Big Sisters New Zealand and Canada, respectively, offer keen insights into the value of creating a shared language for discussing mentoring…

  9. 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…

  10. Teacher's Introduction to African American English, A: What a Writing Teacher Should Know

    ERIC Educational Resources Information Center

    Redd, Teresa M.; Schuster Webb, Karen

    2005-01-01

    In this book, Teresa M. Redd and Karen Schuster Webb explain not only what African American English (AAE) is, but also what role it may play in students' mastery of Standard Written English. Designed especially for writing teachers, this volume is a concise, coherent, and current source that summarizes the major schools of thought about…

  11. 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);…

  12. 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…

  13. Exploratorium: Exploring Water.

    ERIC Educational Resources Information Center

    Brand, Judith, Ed.

    2001-01-01

    This issue of Exploratorium focuses on water and its varied uses in our environment. Articles include: (1) "Adventures with Water" (Eric Muller); (2) "Water: The Liquid of Life" (Karen E. Kalumuck); (3) "Water-Drop Projector" (Gorazd Planinsic); (4) "Waterways and Means" (Pearl Tesler); (5) "Explore Natural Phenomena in the Museum--and Just…

  14. 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…

  15. 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,…

  16. 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…

  17. Getting the Green: Fundraising Campaigns for Community Colleges

    ERIC Educational Resources Information Center

    Grover, Stuart R.

    2009-01-01

    This book offers a comprehensive and detailed look at private fundraising in community colleges. In the foreward, Karen A. Stout, President, Montgomery County Community College, describes it as a "must-read" for aspiring and new community college presidents, academic leaders searching for ways to bring in new dollars to support new programs, and…

  18. 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...

  19. 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)…

  20. 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…

  1. "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…

  2. 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…

  3. 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…

  4. Creating Start-up Companies around NCI Inventions | Poster

    Cancer.gov

    By Karen Surabian, Thomas Stackhouse, and Rose Freel, Contributing Writers, and Rosemarie Truman, Guest Writer The National Cancer Institute (NCI), led by the Technology Transfer Center (TTC),  the Avon Foundation, and The Center for Advancing Innovation have partnered to create a “first-of-a-kind” Breast Cancer Start-up Challenge.

  5. 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 ...

  6. 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...

  7. Visions in the Dust: A Child's Perspective of the Dust Bowl. Learning Page Lesson Plan.

    ERIC Educational Resources Information Center

    King, Jan; Nisbet, Rena

    Much of history is interpreted from an adult point of view. But in Karen Hesse's Newbery Award-winning "Out of the Dust," the Great Depression's Dust Bowl is seen through the eyes of a child. By using the novel, this lesson plan gives students the opportunity to identify with the personal experiences of youth in the 1930s. In addition,…

  8. Working across and with Methodological Difference in Environmental Education Research

    ERIC Educational Resources Information Center

    Russell, Constance L.

    2006-01-01

    In this article, the author discusses the implications of articles by Louise Chawla (1998) and Karen Malone (1999a) for "doing research." One of the most interesting implications of these two papers for environmental education research is the issues they raise about the challenges for environmental education researchers and education researchers…

  9. Coalition for Education in the Outdoors Research Symposium Proceedings (4th, Bradford Woods, Indiana, January 9-11, 1998).

    ERIC Educational Resources Information Center

    Fox, Karen M., Ed.; Foti, Pamela E., Ed.; McAvoy, Leo H., Ed.; Young, Anderson B., Ed.; Ryan, Sean, Ed.; Johnson, Rebecca, Ed.; Bialeschki, M. Deborah, Ed.

    This proceedings contains 13 papers from the 1998 Research Symposium of the Coalition for Education in the Outdoors. Following a preface "Building the Research Foundations of Outdoor Education" (Karen M. Fox, Leo H. McAvoy, Anderson B. Young), the entries are: (1) "An Integrative Review of the Literature on Women in the Outdoors" (Karla A.…

  10. Using Data for School Improvement. Research Brief

    ERIC Educational Resources Information Center

    Education Partnerships, Inc., 2012

    2012-01-01

    How can principals and teachers use available data to plan school improvements? How can principals and teachers gather and analyze data that are useful for school reform? Karen Levesque and her colleagues sum up the problem of data use in schools this way. Most school districts and schools in this country are routinely involved in data collection.…

  11. Playing Their Way into Literacies: Reading, Writing, and Belonging in the Early Childhood Classroom. Language & Literacy Series

    ERIC Educational Resources Information Center

    Wohlwend, Karen E.

    2011-01-01

    Karen Wohlwend provides a new framework for rethinking the boundaries between literacy and play, so that play itself is viewed as a literacy practice along with reading, writing, and design. Through a variety of theoretical lenses, the author presents a portrait of literacy play that connects three play groups: the girls and, importantly, boys,…

  12. Understanding the Business of Library Acquisitions. Second Edition.

    ERIC Educational Resources Information Center

    Schmidt, Karen A., Ed.

    This expanded edition provides new information about successfully managing library acquisitions. Chapters include: "Acquisitions, the Organization, and the Future" (Carol Pitts Diedrichs and Karen A. Schmidt); "The Business of Book Publishing" (Patricia Glass Schuman and Charles Harmon); "The Business of Scholarly Journal Publishing" (Gary J.…

  13. Learning Organization. Symposium 36. [AHRD Conference, 2001].

    ERIC Educational Resources Information Center

    2001

    This symposium on learning organization consists of three presentations. "Perception of Learning Culture and Concerns About the Innovation on Use of Innovation: A Question of Level of Analysis" (Rebecca Fatima Sta. Maria, Karen E. Watkins) reports a study of the relationship between organizational members' perception of learning culture…

  14. Forging a National Strategy for Success

    ERIC Educational Resources Information Center

    Reed, Jack

    2009-01-01

    At the National Staff Development Council's (NSDC's) 40th Annual Conference in December 2008, former NSDC Board President Karen Dyer and Executive Director Stephanie Hirsh presented the first Policy Maker of the Year Award to Senator Jack Reed (D-RI) in recognition of his dedicated work on behalf of legislation that promotes effective professional…

  15. LINWORTH/ALISE 2009 Youth Services Paper: Equal Opportunity? Poverty and Characteristics of School Library Media Centers

    ERIC Educational Resources Information Center

    Pribesh, Shana; Gavigan, Karen

    2009-01-01

    When the authors met through a mutual colleague, Gail Dickinson at Old Dominion University, Karen and Shana set about to examine issues that do not normally interest sociologists--the number of days school libraries are closed and whether or not library schedules (fixed or flexed) impact student achievement. However, Shana, a sociologist who…

  16. NETAC Networks. Providing Technical Assistance to Professionals Working with Students Who Are Deaf and Hard of Hearing

    ERIC Educational Resources Information Center

    Northeast Technical Assistance Center (NETAC), Rochester Institute of Technology, 2005

    2005-01-01

    This issue of "NETAC Networks" highlights the following: (1) A snapshot of life in the U.S. Virgin Islands (Karen Brin); (2) Upcoming events by state; (3) Convert television captions to web-streaming formats; (4) I.D.E.A. reauthorized; (5) Vermont Career Day 2004 (Janet Dickinson); (6) Eye on the prize (Jane Jarrow); (7) Promoting…

  17. 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…

  18. 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:…

  19. Autism and Multidisciplinary Teamwork through the SCERTS Model

    ERIC Educational Resources Information Center

    Molteni, Paola; Guldberg, Karen; Logan, Nick

    2013-01-01

    This research investigates multidisciplinary teamwork in an English special school located in the West Midlands region of the UK. The research was carried out by Paola Molteni, a PhD student at Università Cattolica del Sacro Cuore, Milan, Karen Guldberg of the Autism Centre for Education and Research Director at the University of Birmingham School…

  20. 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…

  1. 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)…

  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…

  3. 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…

  4. Parity for Minorities in the Media. Hearing before the Subcommittee on Telecommunications, Consumer Protection, and Finance of the Committee on Energy and Commerce. House of Representatives, Ninety-Eighth Congress, First Session on H.R. 1155. A Bill to Amend the Communications Act of 1934 to Provide for Greater Participation of Minorities in Telecommunications.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. House Committee on Energy and Commerce.

    This transcript of a hearing on minority participation in telecommunications includes the text of the bill, H.R. 155; a summary of the bill from the Congressional Record; and testimony and statements from both individuals and representatives of several organizations. Testimony was presented by: (1) Karen English, Chicago, Illinois; (2) Janice…

  5. Countertransference with the Older Adult: The Importance of Mental Health Counselor Awareness and Strategies for Effective Management.

    ERIC Educational Resources Information Center

    Brockett, Daniel R.; Gleckman, Ari D.

    1991-01-01

    Defines the concept of countertransference and four dimensions of possible countertransference responses toward the older client. Three of these responses are based on Karen Horney's interpersonal styles: moving toward, moving away, and moving against. Discusses strategies for managing countertransference with older clients, with special emphasis…

  6. 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…

  7. Therapist Autonomy as Countertransference.

    ERIC Educational Resources Information Center

    Leavy, Patricia G.

    This paper discusses N. B. Ralph's (1980) four stages of development for the novice therapist, focusing on the fourth stage (therapists become aware of their own feelings and reactions to the therapeutic process) through the author's experience in therapy. The therapist as client is discussed according to Karen Horney's classification of neurotic…

  8. 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…

  9. 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…

  10. Motion.

    ERIC Educational Resources Information Center

    Brand, Judith, Ed.

    2002-01-01

    This issue of Exploratorium Magazine focuses on the topic of motion. Contents include: (1) "First Word" (Zach Tobias); (2) "Cosmic Collisions" (Robert Irion); (3) "The Mobile Cell" (Karen E. Kalumuck); (4) "The Paths of Paths" (Steven Vogel); (5) "Fragments" (Pearl Tesler); (6) "Moving Pictures" (Amy Snyder); (7) "Plants on the Go" (Katharine…

  11. 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…

  12. 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);…

  13. 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...

  14. Polymerization of Quinone-Crosslinked Marine Bioadhesive Protein

    DTIC Science & Technology

    1988-10-05

    occurred following enzymic oxidation utilizating either mushroom tyrosinase or byssal catechol oxidase , which suggests that the precise nature of the...TRAINING ACTIVITIES Bernardo Estupiftan and Karen Long received their M.S. degrees in the summer of 1988. Thesis titles were: "Study of polyphenolic

  15. RAND Report on Charter Schools and Vouchers.

    ERIC Educational Resources Information Center

    Perkins-Gough, Deborah

    2002-01-01

    Highlights some of the major findings of the December 2001 RAND report on charter schools and vouchers prepared by Brain P. Gill, P. Michael Timpane, Karen E. Ross, and Dominic J. Brewer. The report can be ordered from RAND at www.rand.org/publications. (PKP)

  16. Caring for Multiples

    MedlinePlus

    ... in online discussions, meet other NICU families. Mothering Multiples: Breastfeeding and Caring for Twins or More, by Karen Kerkhoff Gromada (La Leche League International, 1999). Mothers of Super Twins (MOST) A support network of families who have or are expecting triplets, ...

  17. Literacy Strategies for Grades 4?12: Reinforcing the Threads of Reading

    ERIC Educational Resources Information Center

    Tankersley, Karen

    2005-01-01

    In this book, Karen Tankersley provides a multiplicity of practical, research-based reading strategies tailored specifically for use with older students. These students may no longer have a reading class as part of the school day, but they are still developing their reading skills--and every teacher contributes to that effort. As in her previous…

  18. 78 FR 17205 - Notice of Availability of Service Contract Inventories

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-20

    ... Notice of Availability of Service Contract Inventories AGENCY: Federal Maritime Commission. ACTION: Notice of availability of service contract inventories. FOR FURTHER INFORMATION CONTACT: Karen V. Gregory... notice to advise the public of the availability of the FY 2011 Service Contract Inventory Analysis,...

  19. 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…

  20. 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…

  1. 76 FR 72021 - Florida Disaster #FL-00066

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-21

    ... Date: 11/14/2011. Physical Loan Application Deadline Date: 01/13/2012. Economic Injury (EIDL) Loan...: November 14, 2011. Karen G. Mills, Administrator. BILLING CODE 8025-01-P ...: This is a notice of an Administrative declaration of a disaster for the State of Florida dated...

  2. 76 FR 75597 - North Carolina Disaster #NC-00038

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... dated 11/21/2011. Incident: Storms and tornadoes. Incident Period: 11/16/2011. Effective Date: 11/21/2011. Physical Loan Application Deadline Date: 01/20/2012. Economic Injury (EIDL) Loan Application... Assistance Numbers 59002 and 59008) Dated: November 21, 2011. Karen G. Mills, Administrator. BILLING...

  3. 76 FR 72020 - Missouri Disaster #MO-00051

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-21

    ... through 06/27/2011. Effective Date: 11/09/2011. Physical Loan Application Deadline Date: 01/09/2012..., 2011. Karen G. Mills, Administrator. BILLING CODE 8025-01-P ...: This is a notice of an Administrative declaration of a disaster for the State of Missouri dated...

  4. 76 FR 72020 - Virginia Disaster #VA-00039

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-21

    ... 11/14/2011. Incident: Tropical Storm Lee. Incident Period: 09/08/2011 Through 09/09/2011. Effective Date: 11/14/2011. Physical Loan Application Deadline Date: 01/13/2012. Economic Injury (EIDL) Loan...: November 14, 2011. Karen G. Mills, Administrator. BILLING CODE 8025-01-P...

  5. 76 FR 59766 - Oklahoma Disaster #OK-00056

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    .../2011. Incident: Oklahoma County Wildfire. Incident Period: 08/30/2011 through 09/01/2011. Effective Date: 09/21/2011. Physical Loan Application Deadline Date: 11/21/2011. Economic Injury (EIDL) Loan... Assistance Numbers 59002 and 59008) Dated: September 21, 2011. Karen G. Mills, Administrator. BILLING...

  6. 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"…

  7. The End of Lifelong Learning: A Post-Human Condition?

    ERIC Educational Resources Information Center

    Edwards, Richard

    2010-01-01

    This article explores the significance of theories of the post-human for lifelong learning. Drawing upon the works of Karen Barad and Bruno Latour, it suggests that education has focused on the learning subject as a result of an a priori assumption of a separation of matter from meaning, the object from the subject. By contrast, a post-human…

  8. Biological and Commonsense Constructions of Gender.

    ERIC Educational Resources Information Center

    McKenna, Wendy

    Karen Horney's critique of Freud's theory of female development suggests that much theory and research in psychology is androcentric, and calls for the elimination of biases. This point is questioned, and the posit that scientific knowledge does not answer the question of what makes a person either female or male is explored. Biological,…

  9. The Effects of Husband’s At-Sea Time upon the Role Playing Behavior of the Submariner’s Wife

    DTIC Science & Technology

    1978-08-30

    Ombudsmen, and wives of senior enlisted personnel were in- vited to attend the briefing and question and answer period. I! U; 24 BIBLIOGRAPHY Bateson ... Gregory 1972 Culture Contact and Schismogenesis. In Steps to an Ecology of Mind. Pp. 61-72. New York: Ballantine Books (1935). Beckman, Karen __ 1976

  10. 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,…

  11. Navigating the Literacy Waters: Research, Praxis, and Advocacy. The Twenty-Ninth Yearbook: A Peer Reviewed Publication of the College Reading Association. [Papers from the College Reading Association Conference, 2006

    ERIC Educational Resources Information Center

    Foote, Martha M., Ed.; Szabo, Susan, Ed.; Falk-Ross, Francine, Ed.; Sampson, Mary Beth, Ed.

    2008-01-01

    This book presents a selection of the research and papers presented at the 50th Annual Meeting of the College Reading Association in Pittsburgh, Pennsylvania in October, 2006. This Yearbook begins with Karen Bromley's presidential address, which explored the future of writing by discussing four predictions: the notion that pens and pencils will be…

  12. 77 FR 33737 - Findings of Research Misconduct; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-07

    ... HUMAN SERVICES Office of the Secretary Findings of Research Misconduct; Correction AGENCY: Office of the... notice published in the May 31, Federal Register entitled ``Findings of Research Misconduct.'' DATES... Research Misconduct notice published on May 31, 2012. FOR FURTHER INFORMATION CONTACT: Karen Gorirossi...

  13. 76 FR 61403 - Sunshine Federal Register Notice

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-04

    ..., 2011 9 a.m. Briefing on Browns Ferry Unit 1 (Public Meeting). (Contact: Eugene Guthrie, 404-997-4662..., October 6, 2011 9 a.m. Briefing on NRC International Activities (Public Meeting). (Contact: Karen... of October 10, 2011--Tentative Tuesday, October 11, 2011 9 a.m. Briefing on the Japan Near Term...

  14. 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:…

  15. Appraisal of Marist Education in the Light of Patristic Education

    ERIC Educational Resources Information Center

    Osuji, Gregory Ekene; Oluoch-Suleh, Everlyn

    2015-01-01

    The Study evaluated the Marist Brother Lecturer and the Marist Student in Marist International University College, Karen, Nairobi in the light of the Education founded on Christian principles by Jesus Christ and expounded by the early Church Fathers. The Researchers tried to find out the attitude of both Marist Brother Lecturer and Marist Student…

  16. An Investigation of the Appropriateness of Computer-Based Instruction to the Royal Australian Air Force CISCON Mustering

    DTIC Science & Technology

    1995-12-01

    65- 71 (June 1993). Beer, Jeffrey and Karen Freifeld . "Super Tutorials," PC World, 10: 192-194 (May 1992). Bottoms, David T. "Multimedia Delivers the...Scott. "Computer Screen Designs: Viewer Judgments", Educational Technology Research & Development, 41: 35-73 (1993). Hill, David . "Inventing the Future

  17. Life, Liberty, and the Pursuit of Happiness. Materials for Using American Issues Forum in the American History Classroom, Topic IX.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Secondary Curriculum Development.

    Four modules of classroom strategies provide suggestions for examining U.S. history in light of contemporary issues. "The Right to Life" uses the Karen Anne Quinlan case as a model for exploring moral, legal, and medical issues related to euthanasia. Students discuss the reasoning and viewpoints of various groups associated with the…

  18. A Leader's Top Task Is to Nurture Talent

    ERIC Educational Resources Information Center

    Louis, Karen Seashore

    2016-01-01

    In her full essay exploring the Leadership standard in "Reach the Highest Standard in Professional Learning: Leadership," author Karen Seashore Louis offers keen insights into the question of how leaders affect the learning of other adults in a school. She writes particularly about how "school leaders can create a school culture in…

  19. 77 FR 26273 - Environmental Management Site-Specific Advisory Board, Northern New Mexico

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-03

    ... Call and Excused Absences, Karen Erickson. Welcome and Introductions, Ralph Phelps, Chair. Approval of.... Written Reports. Report on Spring EM SSAB Chairs' Meeting, Ralph Phelps and Carlos Valdez. Other Items. 2... Issues. 3:15 p.m. Break. 3:30 p.m. ``State of the Laboratory,'' Pete Maggiore and Michael...

  20. An Evaluation of the Application of a Lock Box System within the Department of the Navy.

    DTIC Science & Technology

    1984-09-01

    literature revealed that lock box services are provided by many major banks throughout the U.S. The Corporate Finance Sourcebook [Ref. 1] lists these banks...I __ L 1 4- ____ ____ ___ ____ _ _ _ _ _ - ~~ - 252 REFERENCES 1. Zehring, Karen (ed.), The Corporate Finance Sourcebook 1980. New York: The

  1. Commensal Bacteria Control Cancer Response to Therapy by Modulating the Tumor Microenvironment | Poster

    Cancer.gov

    Noriho Iida, Amiran Dzutsev, C. Andrew Stewart, Loretta Smith, Nicolas Bouladoux, Rebecca A. Weingarten, Daniel A. Molina, Rosalba Salcedo, Timothy Back, Sarah Cramer, Ren-Ming Dai, Hiu Kiu, Marco Cardone, Shruti Naik, Anil K. Patri, Ena Wang, Francesco M. Marincola, Karen M. Frank, Yasmine Belkaid, Giorgio Trinchieri, Romina S. Goldszmid Science 342(6161):967-970, 2013

  2. A Cauldron of Opposition in Duncan's Hometown: Rank-and-File Teachers Score Huge Victory

    ERIC Educational Resources Information Center

    Rethinking Schools, 2010

    2010-01-01

    In a stunning victory, a group of rank-and-file teachers won election to leadership of the powerful Chicago Teachers Union (CTU) this past June. Karen Lewis, a high school chemistry teacher, defeated the two-time incumbent president, winning 60 percent of the vote. Lewis led a slate of candidates from the Caucus of Rank-and-File Educators (CORE),…

  3. The Objective Force Soldier/Soldier Team. Volume I: Executive Summary

    DTIC Science & Technology

    2001-11-01

    Assistants Mike Hendricks Dennis Gibson Karen Williams Ted Mattus Cherie Smith LTC Tom McWhorter Bob Dodd Tom Conway Wayne Chalupa Cadet Staff Mateo Chino...Integration Agency Mr. Wayne Chalupa DCSPRO-FD Sponsors HON Paul Hoeper Assistant Secretary of the Army for Acquisition, Logistics and

  4. Campaigns to Overrule Campus Gun Bans Have Failed in Many States

    ERIC Educational Resources Information Center

    Lipka, Sara

    2008-01-01

    People can bring guns most places in Arizona, but the state's Board of Regents has long banned all weapons from public college campuses. Now some lawmakers are trying to change that. State Senator Karen S. Johnson, a Republican, proposed a bill in January that would trump the regents' ban, allowing anyone with a concealed-weapons permit to carry a…

  5. 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…

  6. Time and Learning: Scheduling for Success. Hot Topics Series.

    ERIC Educational Resources Information Center

    Kennedy, Robert L., Ed.; Witcher, Ann E., Ed.

    This book provides information for educators considering ways to make the best use of time available for learning. Twenty-one articles are divided into 5 chapters. Chapter 1: "How Can We Make the Most of the School Day?" includes an overview and 6 articles: (1) "Block Scheduling" (Karen Irmsher); (2)"The Hybrid Schedule: Scheduling to the…

  7. Diagramming Assemblages of Sex/Gender and Sexuality as Environmental Education

    ERIC Educational Resources Information Center

    Bazzul, Jesse; Santavicca, Nicholas

    2017-01-01

    This article explores ethico/political/ontological orientations made possible by an exploration of sex/gender and sexuality. Drawing from materialist theorists such as Karen Barad, Gilles Deleuze, and Felix Guattari, we employ the concept of assemblages to tease out the reality that our shared world is always already in a state of queer becoming.…

  8. The Role of Built Environments in Physical Activity, Eating, and Obesity in Childhood

    ERIC Educational Resources Information Center

    Sallis, James F.; Glanz, Karen

    2006-01-01

    Over the past forty years various changes in the U.S. "built environment" have promoted sedentary lifestyles and less healthful diets. James Sallis and Karen Glanz investigate whether these changes have had a direct effect on childhood obesity and whether improvements to encourage more physical activity and more healthful diets are likely to lower…

  9. Aspects of a Modern Business Education Program.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Business Education.

    A collection of six papers by New York business educators deals with criteria for judging the completeness and effectiveness of a business education program. The curriculum, recruitment, program promotion, image, and other aspects of a comprehensive high school program are outlined by C. Irene Schindler. Karen R. Gillespie of New York University…

  10. 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…

  11. 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)…

  12. How Can We Explain Poverty? Case Study of Dee Reveals the Complexities

    ERIC Educational Resources Information Center

    Seccombe, Karen

    2011-01-01

    Many theories have been offered to explain why people are impoverished. This article by Karen Seccombe uses the case study of "Dee," a newly single mother, to explore four of the most common: individualism, social structuralism, the culture of poverty, and fatalism. She concludes that poverty is a highly complex phenomenon, and it is likely that…

  13. 77 FR 70209 - Designation of Seven Entities Pursuant to Executive Order 13448 or Executive Order 13464 and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-23

    ... pursuant to E.O. 13448: 1. GOLD ENERGY CO. LTD., No. 74 Lan Thit Road, Insein Township, Rangoon, Burma; Taungngu (Tungoo) Branch, Karen State, Burma . 2. GOLD OCEAN PTE LTD, 101 Cecil Street 08-08, Tong Eng... Cecil Street 08-08, Tong Eng Building, Singapore, 069533, Singapore . 4. GREEN LUCK TRADING COMPANY...

  14. 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…

  15. New Perspectives in Human Resource Development.

    ERIC Educational Resources Information Center

    1999

    These three papers are from a symposium on new perspectives in human resource development (HRD). "Developing an Instrument to Measure the Use of Play-Based Training Methods in Healthcare Education" (Rebecca J. Adams, Karen E. Watkins, Tom Valentine) reports preliminary findings from a pilot study that tested data collection procedures…

  16. Informal Workplace Learning.

    ERIC Educational Resources Information Center

    1999

    The first of the four papers in this symposium, "Re-conceptualizing Marsick and Watkins' Model of Informal and Incidental Learning in the Workplace" (Maria Cseh, Karen E. Watkins, Victoria J. Marsick) describes the use of a revised model to encompass the learning perspectives of small business owner-managers who work in the volatile…

  17. Superintendents' Husbands: Encourage, Support and Bide Their Free Time

    ERIC Educational Resources Information Center

    Goldman, Jay P.

    2012-01-01

    When Karen Rue was on the verge of accepting her first superintendent appointment 11 years ago, her husband Gary anticipated he might be asked to play the role of "first spouse," serving as informal ambassador for the school district. He was correct. Gary Rue, a retired physical education teacher, has willingly served as his wife's…

  18. Bullying Prevention for School Safety (with Related Video)

    ERIC Educational Resources Information Center

    Johnson, Katie

    2012-01-01

    The nation watched in shock recently as four middle school boys barraged 68-year-old bus monitor Karen Klein with jabs about her weight, attacks on her family, and chuckled as they made violent and graphic threats. Klein remained quiet, taking the abuse and failing to respond to the students. This incident might have gone unnoticed and unreported,…

  19. Distance Education in Southern Africa Conference, 1987. Papers 5: Administration and Student Support in Distance Education.

    ERIC Educational Resources Information Center

    Adey, David, Comp.; And Others

    Seventeen papers from the University of South Africa's Conference on Distance Education are presented. They include: "Establishing a Formal Student Support System--Time Is of the Essence" (Karen Hinrichs); "A Student Services Unit in a Distance Education Institution" (Hendrik Gous); "Distance Education and the Community:…

  20. Discipline-Based Art Education: Its Criticisms and Its Critics.

    ERIC Educational Resources Information Center

    Eisner, Elliot W.

    1988-01-01

    Discusses the criticisms of discipline-based art education published in the March 1988 issue of "Art Education." Responds to the arguments of Peter London, Helen Muth, Norma K. Pittard, and Karen Hamblen. States that art education would be better served if the energy devoted to criticism was directed toward constructive ends. (GEA)

  1. 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…

  2. Information Literacy and its Relationship to Cognitive Development and Reflective Judgment

    ERIC Educational Resources Information Center

    Jackson, Rebecca

    2008-01-01

    This article maps the Association of College and Research Libraries' Information Competency Standards for Higher Education to the cognitive development levels developed by William G. Perry and Patricia King and Karen Kitchener to suggest which competencies are appropriate for which level of cognitive development. (Contains 1 table.)

  3. Tips & Techniques: Storytelling with Puppets and Props. [Videotape].

    ERIC Educational Resources Information Center

    2002

    On this 20-minute videotape, two accomplished storytellers share their expertise on using puppets and props to enhance the art of storytelling. Schroeder Cherry uses several types of puppets to tell his educational story about the Underground Railroad, while Karen Quinn-Wisniewski entertains her audience of young children with classic fables,…

  4. 78 FR 70027 - Senior Executive Service; Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-22

    .... ANDERSON, CYNTHIA V. ANDERSON, ROBERT T. ANDREWS, CLAUDIA R. AOKI, STEVEN NMN ARANGO III, JOSEPH NMN..., JOSEPH A. BEARD, JEANNE M. BEARD, SUSAN F. BEAUSOLEIL, GEOFFREY L. BEKKEDAHL, LARRY N. BELL, MELODY C..., TRACEY L. BLACK, STEVEN K. BOARDMAN, KAREN L. BODI, F. LORRAINE BOLTON JR. EDWARD L. BORGSTROM, CAROL...

  5. 76 FR 46898 - Quarterly Publication of Individuals, Who Have Chosen To Expatriate, as Required by Section 6039G

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-03

    ... BERTHOLD DOROTHY ISABELLE BESSMERT DANIEL BIASUCCI JOHN W BJERTNES MARK ERIK BLACK CRAIG GRANT BODMER... HEURTLEY HANIBAL AMAR T HARTE NEIL D HARTWICH-KNIGHT KAREN HASKELL PRESTON HAMPTON HASTRY JOHN JOSEPH... ROBERT JOSEPH ALLEN PAVLOWSKI DANNY PEACOCK ESTHER CHRISTINE LEHAR PECOT III CHARLES MATTHEW PENMAN...

  6. 77 FR 64967 - Senior Executive Service; Performance Review Board

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-24

    ... ANDERSON, ROBERT T ANDREWS, CLAUDIA R AOKI, STEVEN NMN ARANGO III, JOSEPH NMN ASCANIO, XAVIER NMN ATKINS, ARTHUR G AZAR, LAUREN L BAKER, KENNETH E BARHYDT, LAURA L BATTERSHELL, CAROL J BEAMON, JOSEPH A BEARD... BIERBOWER, WILLIAM J BISHOP, CLARENCE T BISHOP, TRACEY L BLACK, STEVEN K BOARDMAN, KAREN L BODI, F...

  7. 76 FR 64379 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-18

    ... amount of $43.75 (25 cents per page reproduction cost) payable to the U.S. Treasury or, if requesting by... amount of $18.00 (25 cents per page reproduction cost) payable to the U.S. Treasury. Karen...

  8. 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…

  9. 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…

  10. 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.

  11. 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...

  12. Building a Culinary Arts Academy

    ERIC Educational Resources Information Center

    Brown, Robert L.

    2005-01-01

    When Judy Karen Brown (the 2004 Alabama Family and Consumer Sciences Teacher of the Year) arrived at Bob Jones High School (BJHS) in Madison, Alabama, in the summer of 1999, she immediately identified a need to build both student and community interests in family and consumer sciences (FACS). She noticed the student and faculty interest in the…

  13. The Process of the Learning Organization: Making Sense of Change.

    ERIC Educational Resources Information Center

    Bierema, Laura L.

    1999-01-01

    Compares definitions and core elements of learning organizations promulgated by Peter Senge, Victoria Marsick and Karen Watkins, Nancy Dixon, Michael Marquardt, Mike Pedler, and others. Discusses leadership implications and the need for employees to create a new learning infrastructure incorporating new leaders, critical thinking, and envisioning.…

  14. 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…

  15. Foundation for Child Development Annual Report, 2001-2002.

    ERIC Educational Resources Information Center

    Foundation for Child Development, New York, NY.

    This annual report details the activities of the Foundation for Child Development (FCD) for 2001-2002. Beginning the report is a brief description of the Foundations mission, its funding priorities, and application procedures. The report then presents the joint statement of the chair, Karen Gerard, and the president, Ruby Takanishi, focusing on…

  16. 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…

  17. What's Good about the Best?

    ERIC Educational Resources Information Center

    Hipple, Ted; Maupin, Amy B.

    2001-01-01

    Discusses three award-winning novels for young adults that are very popular with school teachers: "The Giver" by Lois Lowry, "Out of the Dust" by Karen Hesse, and "Holes" by Louis Sachar. Examines the quality of plots, characters, and themes but also considers the artistry in details and emotional impact. Offers…

  18. 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)

  19. Moving Ideas to Impact. To Change the Odds for Youth: Charting the Forum's Course to 2010. President's Remarks

    ERIC Educational Resources Information Center

    Pittman, Karen

    2005-01-01

    Reflecting on her life as a teen growing up in the low-income neighborhoods of Washington, DC, Karen Pittman spells out why she is determined to have the Forum meet its goal of challenging national partners and state and local change makers to ensure that every young person is Ready by 2010. Pittman describes what she believes is the biggest…

  20. Petrographic and chemical characteristics of the Panda Hill carbonatite complex, Tanzania

    NASA Astrophysics Data System (ADS)

    Basu, Nitin Kumar; Mayila, Agnes

    The Panda Hill carbonatite complex, situated near the south-western flank of the Rukwa Trough in south-western Tanzania, comprises a carbonatite body, a fenite aureole and feldspathic agglomerate and breccia. Petrographic study, supported by some analyses of both rocks and minerals, indicates that the fenite zone and the agglomerate and breccia are very rich in potash. Fenites consist mainly of monomineralic orthoclase rock grading to basement gneiss away from the carbonate body. Fragments of agglomerates range from feldspathic fenites to altered basement gneiss with some fragments carbonatized. The central plug and most of the carbonatite body consist of sövite. Beforsite occurs as dyke-like bodies often cutting across flow-lines of sövite. Beforsite forms the outermost boundary of the carbonatite body on the south-east. Ferrocarbonatite forms the outermost boundary of the main body in the eastern foothills. A number of pseudo-phoscorite layers are associated with sövite often imparting a flow structure to the rock. Several mafic dykes intrude into the main carbonatite body. All these dykes are more or less carbonatized. Two types of mafic dykes are distinguished: carbonatized lamprophyre dykes; dolerite dykes. The primary magma from which the Panda Hill carbonatite and its associates originated appears to have had a potash-rich fraction. Explosiv eruption of alkali-rich magma and influx of alkali-rich solution led to extensive fenitization. The central plug indicates forceful injection of the body simultaneously with the explosive eruption. The distribution of tuffs and volcanic breccia around three hill-tops shows existence of volcanic vents. Intrusion of minor dykes of mafic and ultramafic rocks took place along with the intrusion of the carbonatite plug. During falling temperature, permeation of the country rocks surrounding the carbonatite body by carbonate fluids caused partial replacement of all the minerals by carbonates.

  1. Palaeomagnetic study of a subaerial volcanic ridge (São Jorge Island, Azores) for the past 1.3 Myr: evidence for the Cobb Mountain Subchron, volcano flank instability and tectonomagmatic implications

    NASA Astrophysics Data System (ADS)

    Silva, P. F.; Henry, B.; Marques, F. O.; Hildenbrand, A.; Madureira, P.; Mériaux, C. A.; Kratinová, Z.

    2012-03-01

    We present a palaeomagnetic study on 38 lava flows and 20 dykes encompassing the past 1.3 Myr on S. Jorge Island (Azores Archipelago—North Atlantic Ocean). The sections sampled in the southeastern and central/western parts of the island record reversed and normal polarities, respectively. They indicate a mean palaeomagnetic pole (81.3°N, 160.7°E, K= 33 and A95= 3.4°) with a latitude shallower than that expected from Geocentric Axial Dipole assumption, suggesting an effect of non-dipolar components of the Earth magnetic field. Virtual Geomagnetic Poles of eight flows and two dykes closely follow the contemporaneous records of the Cobb Mountain Subchron (ODP/DSDP programs) and constrain the age transition from reversed to normal polarity at ca. 1.207 ± 0.017 Ma. Volcano flank instabilities, probably related to dyke emplacement along an NNW-SSE direction, led to southwestward tilting of the lava pile towards the sea. Two spatially and temporally distinct dyke systems have been recognized on the island. The eastern is dominated by NNW-SSE trending dykes emplaced before the end of the Matuyama Chron, whereas in the central/western parts the eruptive fissures oriented WNW-ESE controlled the westward growth of the S. Jorge Island during the Brunhes Chron. Both directions are consistent with the present-day regional stress conditions deduced from plate kinematics and tectonomorphology and suggest the emplacement of dykes along pre-existing fractures. The distinct timing and location of each dyke system likely results from a slight shift of the magmatic source.

  2. The structure and evolution of magmatic complexes in fold-and-thrust belts - a case study of Cerro Negro, Neuquén Province, Argentina

    NASA Astrophysics Data System (ADS)

    Gürer, D.; Galland, O.; Leanza, H. A.; Sassier, C.; Cobbold, P. R.; Rossello, E. A.

    2012-04-01

    In contrast to the classical concept of magma ascent in extensional settings, recent studies show that volcanism also occurs in compressional settings. The nature of the interplay between magmatism and tectonics in fold-and-thrust belts however, remains a major question, notably in active margins. The mechanisms of magma transport in such settings and whether magmatism affects tectonic deformation need to be addressed. Therefore, we carried out detailed structural mapping and sampling of an intrusive complex: the Cerro Negro of Tricao Malal, Neuquén Province, Argentina. This intrusive system belongs to a magmatic province that intruded into the intensely deformed Agrio fold-and-thrust belt, located between 37°S and 38°S in the Argentinean foothills of the Andes. The fold-and-thrust belt has resulted from intense E-W shortening, and contains tight folds and thrusts, trending N-S. The intrusive complex crops out as a network of sills and dykes around a main intrusion, all of which are of andesitic composition. The plumbing system of Cerro Negro is well exposed so that the structural relations between the intrusions and the tectonic structures can be studied. We have identified at least two generations of intrusions: two thick sills that predate or are coeval with deformation, and numerous sub-vertical dykes that strike N-S, i.e. perpendicular to the shortening. We observed that the main intrusive body and the dykes have formed in a central anticline, the dykes being close to the hinge. Furthermore, the dykes crosscut folded sills, postdating all visible deformation. From the structural and temporal relationships between the anticline and the dykes, we infer that local stresses controlled the formation of the dykes during outer-arc stretching. This illustrates how tectonic deformation may control magma emplacement. Conversely, the traces of the main tectonic structures curve around the intrusive complex, suggesting that the latter influenced the tectonic

  3. Witnessing the birth of a new ocean? The first 6 years of the Dabbahu rifting episode, and other activity in Afar

    NASA Astrophysics Data System (ADS)

    Wright, T.; Ayele, A.; Barnie, T.; Belachew, M.; Calais, E.; Field, L.; Hamling, I.; Hammond, J.; Keir, D.

    2012-04-01

    Intense earthquake activity and a small rhyolitic eruption in September 2005 heralded the onset of an unprecedented period of geological activity in the Afar Depression. The seismic activity accompanied dyke intrusion in the upper 10 km of crust along 60 km of the Dabbahu (northern Manda-Hararo) Magmatic Segment (DMS) of the Nubia-Arabia plate boundary, a nascent seafloor spreading centre. InSAR observations of the resulting deformation showed that the initial dyke was up to 8 m thick, with a total volume of 2-2.5 km3. Urgency funding from the UK Natural Environmental Research Council (NERC) and US National Science Foundation (NSF) enabled us to deploy a local array of seismometers in October 2005, continuous GPS instruments in January 2006, and to acquire a dense time series of satellite radar images. The medium-term viability of these instruments was secured with major follow-on funding from NSF and NERC; these projects supported the collection and analysis of additional unique data sets, including data from a broader array of seismic and GPS instruments, magneto-telluric transects of the rift, airborne LiDAR, petrological sampling and micro-gravity work. The combination of these data has allowed us to quantify the processes associated with crustal growth at divergent plate boundaries for the first time. Here, we present a broad overview of geological activity in the Afar depression in the hyperactive 21st century. Activity in the DMS began after September 2000, when Gabho volcano at the north of the segment began uplifting, as its magma chamber, ~3 km below the surface, was replenished. It is likely that the inflation at Gabho ultimately triggered the onset of the Dabbahu rifting episode. The rifting episode began with intense seismicity at the northern end of the DMS, before jumping to the Ado Ale Volcanic Complex at the segment centre. This initial dyking was fed from shallow (~3 km) chambers at Gabho and Dabbahu as well as a deeper (~10 km) source at Ado Ale

  4. 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

  5. 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.

  6. 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

  7. Seismically induced soft-sediment deformation structures revealed by X-ray computed tomography of boring cores

    NASA Astrophysics Data System (ADS)

    Nakashima, Yoshito; Komatsubara, Junko

    2016-06-01

    X-ray computed tomography (CT) allows us to visualize three-dimensional structures hidden in boring cores nondestructively. We applied medical X-ray CT to cores containing seismically induced soft-sediment deformation structures (SSDSs) obtained from the Kanto region of Japan, where the 2011 off the Pacific coast of Tohoku Earthquake occurred. The CT images obtained clearly revealed various types of the seismically induced SSDSs embedded in the cores: a propagating sand dyke bent complexly by the preexisting geological structure, deformed laminations of fluidized sandy layers, and two types of downward mass movement (ductile downward folding and brittle normal faulting) as compensation for upward sand transport through sand dykes. Two advanced image analysis techniques were applied to the sand dyke CT images for the first time. The GrowCut algorithm, a specific digital image segmentation technique that uses cellular automata, was used successfully to extract the three-dimensional complex sand dyke structures embedded in the sandy sediments, which would have been difficult to achieve using a conventional image processing technique. Local autocorrelation image analysis was performed to detect the flow pattern aligned along the sand dykes objectively. The results demonstrate that X-ray CT coupled with advanced digital image analysis techniques is a promising approach to studying the seismically induced SSDSs in boring cores.

  8. 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.

  9. 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.

  10. Subsolidus physical and chemical mixing of granite and gabbro during mylonitization, South Victoria Land, Antarctica

    NASA Astrophysics Data System (ADS)

    Rachel Walcott, C.; Craw, Dave

    1993-12-01

    At Dromedary Massif, Southern Victoria Land, Antarctica, a suite of coarse-grained granite dykes cross-cuts a gabbro pluton which has been partially metamorphosed at amphibolite facies. During regional deformation, strain has been inhomogeneously distributed through the gabbro pluton and has been concentrated in granite dykes. In zones of relatively high strain, the granite dykes have developed a mylonitic fabric. A high strain gradient between granitic mylonite and metagabbroic host rock has induced isochemical mylonitization of the margin of the host. This grain size reduction allowed chemical diffusion between granitic and metagabbroic mylonites, resulting in a marginal zone of biotite-rich mylonite with intermediate composition. Biotite-rich mylonite decoupled from metagabbroic mylonite and flowed with granitic mylonite. Continued folding and transposition of granitic mylonite and biotite-rich mylonite has produced compositionally banded mylonite zones through thorough and irreversible mixing of the two lithologies.

  11. Modes of faulting at mid-ocean ridges.

    PubMed

    Buck, W Roger; Lavier, Luc L; Poliakov, Alexei N B

    2005-04-07

    Abyssal-hill-bounding faults that pervade the oceanic crust are the most common tectonic feature on the surface of the Earth. The recognition that these faults form at plate spreading centres came with the plate tectonic revolution. Recent observations reveal a large range of fault sizes and orientations; numerical models of plate separation, dyke intrusion and faulting require at least two distinct mechanisms of fault formation at ridges to explain these observations. Plate unbending with distance from the top of an axial high reproduces the observed dip directions and offsets of faults formed at fast-spreading centres. Conversely, plate stretching, with differing amounts of constant-rate magmatic dyke intrusion, can explain the great variety of fault offset seen at slow-spreading ridges. Very-large-offset normal faults only form when about half the plate separation at a ridge is accommodated by dyke intrusion.

  12. 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

  13. Mantle metasomatism: the REE story.

    USGS Publications Warehouse

    Wilshire, H.G.

    1984-01-01

    Refractory rocks with light REE/heavy REE ratios > chondrites are common as xenoliths in basalts and kimberlites and are found in some oceanic peridotite massifs. Structural and major-element geochemical evidence from these rocks suggest that the metasomatic effects resulting in addition of light REE are local and are related to emplacement of partial melts. The melts are represented by dykes of pyroxenites, hydrous minerals and gabbro that were emplaced in mantle peridotites of various origins. Metasomatic interaction between dykes and peridotite wall rock results in light REE enrichment in peridotite and depletion in dykes relative to the original liquid. Differentiation of the intrusions and separation of residual liquids may further enhance the REE exchange and extend the volume of metasomatized peridotite. Differences in the relative abundances of altered peridotite in xenoliths and massifs are seen as a sampling problem rather than a difference in process.-L.diH.

  14. Centrifuge modeling of surface structure on normally consolidated silty sand deposited in layers under water and subjected to seismic excitation

    NASA Astrophysics Data System (ADS)

    Gutierrez, Aurelio Manuel

    1998-09-01

    The main objective of this study was to evaluate the effect of strong earthquake shaking on small earth embankments on water saturated loose silty sand deposits---such the existing 5 to 6 meters high dykes along Lake Maracaibo in Venezuela---using centrifuge modeling and simplified but realistic representation of both layered sandy soil and earth structure. The effects studied included the liquefaction of the sandy soil and the permanent settlement of the crest of the dyke due to the earthquake shaking. Fourteen centrifuge tests were conducted with the soils from Lake Maracaibo and a model of foundation on top of the soil. A soil deposit about 9 meters thick was modeled. Parameters studied included shaking acceleration, frequency and duration, sand type, sand fabric, and soil permeability. A curve of vertical displacement of the top of foundation or dyke versus number of cycles of shaking is proposed, which can be used to calibrate computer codes for more general numerical evaluations.

  15. Effects of coastal managed retreat on mercury biogeochemistry.

    PubMed

    Sizmur, Tom; Godfrey, Adam; O'Driscoll, Nelson J

    2016-02-01

    We investigated the impact of managed retreat on mercury (Hg) biogeochemistry at a site subject to diffuse contamination with Hg. We collected sediment cores from an area of land behind a dyke one year before and one year after it was intentionally breached. These sediments were compared to those of an adjacent mudflat and a salt marsh. The concentration of total mercury (THg) in the sediment doubled after the dyke was breached due to the deposition of fresh sediment that had a smaller particle size, and higher pH. The concentration of methylmercury (MeHg) was 27% lower in the sediments after the dyke was breached. We conclude that coastal flooding during managed retreat of coastal flood defences at this site has not increased the risk of Hg methylation or bioavailability during the first year. As the sediment becomes vegetated, increased activity of Hg-methylating bacteria may accelerate Hg-methylation rate.

  16. 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

  17. Fractionation of Mantle-Derived Melts in the Annieopsquotch Ophiolite, Newfoundland.

    NASA Astrophysics Data System (ADS)

    Lissenberg, C.; Bédard, J. H.; van Staal, C. R.

    2004-12-01

    The Annieopsquotch ophiolite exposes a tectonically bounded section through c. 5.5 km tholeiitic gabbros, sheeted dykes and pillow basalts. The gabbro zone is divided into three parts. The lower 500 m comprises massive cumulate gabbros with enclaves (<50 m) of partly-reacted and digested layered troctolite/leucotroctolite. These are interpreted as relics of the substrate into which the gabbro-sheeted dyke-basalt sequence was emplaced. Overlying this is 1500 m of cumulate olivine gabbros and gabbros which form sills c. 30 m thick that are oriented parallel to the ophiolite pseudostratigraphy. Finer grain sizes at contacts and inward-growing crescumulates indicate cooling from both top and bottom. Gabbros in the sill complex are characterized by cumulate textures with minor intercumulus amphibole and oxides, and rarely show shape-preferred orientations. The upper 500 m of the gabbro zone is dominated by massive gabbros with more abundant interstitial Fe-Ti-oxides, and diabasic pods that grade up into sheeted dykes, suggesting it represents a level of frozen melt. Incompatible element contents of cumulate gabbros in the sill complex generally increase upwards, and modeling indicates that the cumulate sills crystallized from melts with compositions similar to those of the overlying sheeted dykes and basalts. Trapped melt fractions are estimated to be c. 20%, consistent with the absence of compaction structures in these gabbros. Models indicate that the parental magmas of the gabbros, as well as lavas and dykes, can be produced by an average of c. 40-45% fractionation of mantle-derived melts. Both field- and geochemical data thus suggests the Annieopsquotch lower crust records repeated in-situ intrusion and fractionation during upward migration of mantle-derived melts towards the surface, with localized ponding in an axial melt lens at the base of the dyke complex. The similarity in composition and degree of fractionation between the lower and upper crust suggest that

  18. Petrography, geochemistry and geochronology of granite hosted rhyodacites associated with a disseminated pyrite mineralization (Arnolz, Southern Bohemian Massif, Austria)

    NASA Astrophysics Data System (ADS)

    Göd, Richard; Kurzweil, Johannes; Klötzli, Urs

    2016-09-01

    The study focuses on a subvolcanic rhyodacite dyke intruding a fine grained biotite granite and paragneisses of the South Bohemian Massif, part of the Variscan Orogenic Belt in Central Europe. The subvertical dyke strikes NNE, displays a thickness of about 30 m and has been traced by boulder mapping for approximately 7 km. The rhyodacites have been affected by two hydrothermal fluids. An older one of oxidizing condition giving rise to a reddish to brownish type of rock (Type I) and a younger fluid of reducing condition causing a greenish variety (Type II). The hydrothermal alteration is associated with the formation of the clay minerals chlorite, sericite, kaolinite and smectite and a disseminated pyrite mineralization. Bulk chemistries of the rhyodacites emphasize the hydrothermal alterations to be isochemical with the exception of sulphur enriched up to a maximum of 0.6 wt%. Trace element composition of the rhyodacites points to a barren geochemical environment in terms of base and precious elements. Sulphur isotope investigations of pyrites from the rhyodacites and the hosting granites respectively yield d34S data ranging from +0.07 to -2.22 ‰, emphasizing a magmatic origin of the sulphur. Geochronological investigations yield in situ U/Pb zircon ages of 312 ± 4 Ma for the biotite granite and of 292 ± 4 Ma for the rhyodacitic dykes indicating a time gap of ≈ 20 Ma between these two intrusive events. A contemporaneous but geochemically specialized granitic intrusion associated with NW striking "felsitic" dykes occurs about 10 to 20 km to the NW of Arnolz. However, the rhyodacites around Arnolz differ significantly from these felsitic dykes in their geochemistry and alteration phenomena which points to a different magmatic source. This coincides with a change in the orientation of the dykes from a NW direction controlling the geochemically specialized intrusions in the NW to a dominating NNE direction mirrored by the studied rhyodacites at Arnolz.

  19. Emplacement age and thermal footprint of the diamondiferous Ellendale E9 lamproite pipe, Western Australia

    NASA Astrophysics Data System (ADS)

    Evans, Noreen J.; McInnes, Brent I. A.; McDonald, Brad; Danišík, Martin; Jourdan, Fred; Mayers, Celia; Thern, Eric; Corbett, Dudley

    2013-03-01

    The diamondiferous Ellendale 9 (E9) pipe is a funnel-shaped maar-diatreme volcano consisting of inward-dipping tuff sequences intruded by lamproite plugs and dykes. The host rocks for the E9 pipe are Permian sandstones. The multiple lithological contacts exposed within the mined maar volcano provide a natural laboratory in which to study the effect of volcanic processes on U-Th-Pb-He systematics. Zircon from the regional sandstone and E9 lamproite display a bimodal distribution of ages on (U-Th)/He-U/Pb plots. The zircon U/Pb ages for the E9 pipe ( n = 52) range from 440 to 2,725 Ma, while the cluster of (U-Th)/He ages for the lamproite dyke zircon indicate that dyke emplacement occurred at 20.6 ± 2.8 Ma, concordant with a maximum emplacement age of about ≤22 Ma from phlogopite 40Ar/39Ar. These ages indicate a xenocrystic origin for the zircon entrained in the E9 dyke. The U/Pb ages of detrital zircon from the regional sandstone host (373-3,248 Ma; n = 41) are indistinguishable from those of the lamproite zircon xenocrysts, whereas the detrital zircon in the host sandstone yield (U-Th)/He ages from 260 to 1,500 Ma. A thermochronology traverse across the E9 lamproite dyke reveals that the zircon (U-Th)/He ages in the host sandstone have not been significantly thermally reset during dyke emplacement, even at the contact. The capability of the zircon (U-Th)/He method to distinguish deep, mantle source lithologies from upper crustal source lithologies could be used in geochemical exploration for diamonds. Pre-screening of detrital samples using etching and helium assay methods will improve the efficiency and decrease the cost of greenfields exploration.

  20. 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.