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Sample records for southern sudan implications

  1. Yellow Fever Outbreak, Southern Sudan, 2003

    PubMed Central

    Onyango, Clayton O.; Grobbelaar, Antoinette A.; Gibson, Georgina V.F.; Sang, Rosemary C.; Sow, Abdourahmane; Swanepoel, Robert

    2004-01-01

    In May 2003, an outbreak of fatal hemorrhagic fever, caused by yellow fever virus, occurred in southern Sudan. Phylogenetic analysis showed that the virus belonged to the East African genotype, which supports the contention that yellow fever is endemic in East Africa with the potential to cause large outbreaks in humans. PMID:15498174

  2. Yellow Fever Outbreak, Imatong, Southern Sudan

    PubMed Central

    Ofula, Victor O.; Sang, Rosemary C.; Konongoi, Samson L.; Sow, Abdourahmane; De Cock, Kevin M.; Tukei, Peter M.; Okoth, Fredrick A.; Swanepoel, Robert; Burt, Felicity J.; Waters, Norman C.; Coldren, Rodney L.

    2004-01-01

    In May 2003, the World Health Organization received reports about a possible outbreak of a hemorrhagic disease of unknown cause in the Imatong Mountains of southern Sudan. Laboratory investigations were conducted on 28 serum samples collected from patients in the Imatong region. Serum samples from 13 patients were positive for immunoglobulin M antibody to flavivirus, and serum samples from 5 patients were positive by reverse transcription–polymerase chain reaction with both the genus Flavivirus–reactive primers and yellow fever virus–specific primers. Nucleotide sequencing of the amplicons obtained with the genus Flavivirus oligonucleotide primers confirmed yellow fever virus as the etiologic agent. Isolation attempts in newborn mice and Vero cells from the samples yielded virus isolates from five patients. Rapid and accurate laboratory diagnosis enabled an interagency emergency task force to initiate a targeted vaccination campaign to control the outbreak. PMID:15207058

  3. 31 CFR 538.532 - Humanitarian transshipments to or from Southern Sudan and Darfur authorized.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Southern Sudan and Darfur authorized. 538.532 Section 538.532 Money and Finance: Treasury Regulations... Humanitarian transshipments to or from Southern Sudan and Darfur authorized. The transit or transshipment to or from Southern Sudan and Darfur of goods, technology, or services intended for humanitarian...

  4. 31 CFR 538.532 - Humanitarian transshipments to or from Southern Sudan and Darfur authorized.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... from Southern Sudan and Darfur authorized. 538.532 Section 538.532 Money and Finance: Treasury....532 Humanitarian transshipments to or from Southern Sudan and Darfur authorized. The transit or transshipment to or from Southern Sudan and Darfur of goods, technology, or services intended for...

  5. Viewing the Reconstruction of Primary Schooling in Southern Sudan through Education Data, 2006-2009

    ERIC Educational Resources Information Center

    Kim, HyeJin; Moses, Kurt D.; Jang, Bosun; Wils, Annababette

    2011-01-01

    After one of the longest wars in the history of Africa, Southern Sudan accomplished one of the world's quickest education reconstruction programmes. Once the Comprehensive Peace Agreement (CPA) was signed in 2005, the international donor community and the government and people of Southern Sudan united under a common goal: to increase access to…

  6. Sudan.

    PubMed

    1984-05-01

    The Sudan currently has a population of 18,618,000, with an annual rate of population growth of 3.1% and a rate of natural increase of 2.8%. Population size estimates for the year 2000 range from 32,064,000-33,762,000. The Sudan does not have an explicit policy to modify population growth, although the government is currently in the early stages of formulating a population policy. The current population growth rate is considered satisfactory because of the lack of population pressure on presently developed land, large areas of undeveloped land and unutilized agricultural potential, and low levels of open unemployment. However, the government seeks to modify spatial distribution to attain a better balance between population and resources. This will be accomplished through social infrastructure investments in rural and desert areas, regional development, sedentarization of nomads, development of new towns, and administrative decentralization. In addition, there is major concern with the high influx of undocumented workers and refugees and the significant emigration of skilled personnel. Life expectancy at birth stands at 45.1 years and the infant mortality rate is 131/1000. Current levels and trends of mortality are considered unacceptably high. Major health problems include schistosomiasis, malaria, malnutrition, infectious childhood diseases, and unsafe water. Primary health care is being prioritized to reduce regional differentials in health status and increase accessibility to health services. The total fertility rate has remained constant at 6-7 births/woman, but the government has been cautious with regard to family planning because of generally negative attitudes of Sudanese women toward birth control. Family planning has been integrated into maternal and child health services, although close to half of all ever-married women have never heard of family planning methods and only 6% of currently married fecund women are contraceptive users. The chief acceptors

  7. Collaborative Evaluation and Market Research Converge: An Innovative Model Agricultural Development Program Evaluation in Southern Sudan

    ERIC Educational Resources Information Center

    O'Sullivan, John M.; O'Sullivan, Rita

    2012-01-01

    In June and July 2006 a team of outside experts arrived in Yei, Southern Sudan through an AID project to provide support to a local agricultural development project. The team brought evaluation, agricultural marketing and financial management expertise to the in-country partners looking at steps to rebuild the economy of the war ravaged region. A…

  8. Jebel Moya (Sudan): new dates from a mortuary complex at the southern Meroitic frontier

    PubMed Central

    Brass, Michael; Schwenniger, Jean-Luc

    2013-01-01

    This paper proposes a new chronology for the burial complex at Jebel Moya, south-central Sudan. It reassesses the body of evidence from Sir Henry Wellcome's original 1911–1914 excavations in order to place the site within a firm chronological framework by: (a) applying an attribute-based approach to discern discrete pottery assemblages; and (b) applying initial OSL dates to facilitate the reliable dating of this site for the first time. Jebel Moya is re-interpreted as a burial complex situated on the southern periphery of the late Meroitic state, and its potential to serve as a chronological and cultural reference point for future studies in south-central and southern Sudan is outlined. PMID:25400300

  9. Collaborative evaluation and market research converge: an innovative model agricultural development program evaluation in Southern Sudan.

    PubMed

    O'Sullivan, John M; O'Sullivan, Rita

    2012-11-01

    In June and July 2006 a team of outside experts arrived in Yei, Southern Sudan through an AID project to provide support to a local agricultural development project. The team brought evaluation, agricultural marketing and financial management expertise to the in-country partners looking at steps to rebuild the economy of the war ravaged region. A partnership of local officials, agricultural development staff, and students worked with the outside team to craft a survey of agricultural traders working between northern Uganda and Southern Sudan the steps approach of a collaborative model. The goal was to create a market directory of use to producers, government officials and others interested in stimulating agricultural trade. The directory of agricultural producers and distributors served as an agricultural development and promotion tool as did the collaborative process itself. PMID:22309968

  10. Jebel Moya (Sudan): new dates from a mortuary complex at the southern Meroitic frontier.

    PubMed

    Brass, Michael; Schwenniger, Jean-Luc

    2013-12-01

    This paper proposes a new chronology for the burial complex at Jebel Moya, south-central Sudan. It reassesses the body of evidence from Sir Henry Wellcome's original 1911-1914 excavations in order to place the site within a firm chronological framework by: (a) applying an attribute-based approach to discern discrete pottery assemblages; and (b) applying initial OSL dates to facilitate the reliable dating of this site for the first time. Jebel Moya is re-interpreted as a burial complex situated on the southern periphery of the late Meroitic state, and its potential to serve as a chronological and cultural reference point for future studies in south-central and southern Sudan is outlined. PMID:25400300

  11. 76 FR 35507 - Assistance to Southern Sudan and the United States Contribution to the Global Fund To Fight AIDS...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-17

    ... Assistance to Southern Sudan and the United States Contribution to the Global Fund To Fight AIDS... Waiver Determination under Section 202(d)(4)(A)(ii) of the United States Leadership against HIV/AIDS... determination under Section 202(d)(4)(A)(ii) of the United States Leadership Against HIV/AIDS, Tuberculosis,...

  12. Interactions and Pastoralism Along the Southern and Southeastern Frontiers of the Meroitic State, Sudan

    PubMed Central

    2016-01-01

    The Nilotic Meroitic state, in what is now the Sudan, existed from the late fourth century BC until the mid fourth century AD. It has come to be regarded in recent years as an African segmentary state with a prestige-goods economy, less centralised than, for example, Egypt, with direct control by the ruling family diminished outside the Shendi Reach (central Sudan). Outbound trade from its capital Meroe included ebony, elephants, gold, iron, ivory and ostrich feathers. Trade routes criss-crossed the desert and extended down the Nile river to Greco-Roman Egypt, as well as through Red Sea ports to several Middle Eastern destinations including Egypt. Using the southern and southeastern reaches of the Meroitic state as a case study, I argue that to conceptualise the frontier peripheries of early states as borders is to misunderstand their internal dynamics (movements of people, fluid social networks and regional exchange systems). Each region had its own distinctive form of power relations. Examining how communities in these frontier zones were constituted, inscribed their identities in the landscape and facilitated trade in relation to the core of the Meroitic state in the Shendi Reach draws attention to the fluidity and continual renegotiation of state–pastoral relations. PMID:27158190

  13. The epidemiology of trachoma in Eastern Equatoria and Upper Nile States, southern Sudan.

    PubMed Central

    Ngondi, Jeremiah; Onsarigo, Alice; Adamu, Liknaw; Matende, Ibrahim; Baba, Samson; Reacher, Mark; Emerson, Paul; Zingeser, James

    2005-01-01

    OBJECTIVE: Limited surveys and anecdotal data indicate that trachoma is endemic in the states of Eastern Equatoria and Upper Nile in southern Sudan. However, its magnitude and geographical distribution are largely unknown. We conducted surveys to ascertain the prevalence and geographical distribution of trachoma, and to identify targets for control interventions. METHODS: Population-based cross-sectional surveys were conducted in nine sites in southern Sudan between September 2001 and June 2004. Two-stage random cluster sampling with probability proportional to size was used to select the sample. Trachoma grading was done using the WHO simplified grading system. FINDINGS: A total of 17 016 persons were examined, a response rate of 86.1% of the enumerated population. Prevalence of signs of active trachoma in children aged 1-9 years was: TF=53.7% (95% confidence interval (CI)=52.1-55.3); TI=42.7% (95% CI=41.2-44.2); TF and/or TI=64.1% (95% CI=62.5-65.5). Prevalence of trichiasis (TT) in children aged less than 15 years was 1.2% (95% CI=0.9-1.4), while TT prevalence in persons aged 15 years and above was 9.2% (95% CI=8.6-9.9). Women were more likely to have trichiasis compared to men (odds ratio (OR)=1.57; 95% CI=1.34-1.84). Tentative extrapolation to the states of Eastern Equatoria and Upper Nile estimates that there is a backlog of 178,250 (lower and upper bounds=156,027-205,995) persons requiring surgery and the entire population, estimated to be over 3.9 million, is in need of the SAFE strategy to control blinding trachoma. CONCLUSION: Trachoma is a public health problem in all nine of the study sites surveyed. The unusually high prevalence of active trachoma and TT in children points to the severity of the problem. There is urgent need to implement trachoma control interventions in trachoma endemic regions of southern Sudan. PMID:16462982

  14. Lessons learned from translators and interpreters from the Dinka tribe of southern Sudan.

    PubMed

    Baird, Martha B

    2011-04-01

    This article discusses the methodological challenges associated with working with translators and interpreters from the Dinka tribe of southern Sudan during an ethnographic study with refugee Dinka women who were resettled with their children in the United States. Navigating the cultural differences between the researcher, the translator, and the interpreters provided a deeper understanding about the culture of the study population. The lessons learned included the importance of cultural congruence between the interpreters and participants; the education, training, and experience of the interpreters; and the difficulties encountered in preparing interpreters according to university institutional review board requirements. Cultural differences such as time perception and communication and literacy styles were negotiated throughout each phase of the study. The most valuable lesson learned from this experience was the importance of the relationship between the researcher, the translator, and the interpreters as well as between the interpreters and participants to achieve credibility and trustworthiness of the study results. PMID:21317404

  15. Issues of expressed stigma of HIV/AIDS among professionals in Southern Sudan.

    PubMed

    Machine, Edwin M; Ross, Michael W; McCurdy, Sheryl A

    2011-08-01

    HIV-related stigma continues to be a significant barrier to HIV testing, treatment, and care. Understanding the factors that underlie this stigma could help remove barriers to HIV/AIDS intervention. We identified these factors among nurses as well as community leaders in Lui, Southern Sudan. Participants included health workers at a local hospital, a women's group, local market traders, religious leaders, and teachers. We categorized the responses generated from group interaction forums as concerns, fears, and perceptions. We found that stigma persisted not only toward people with conspicuous signs of full-blown AIDS, but also toward community programs, like voluntary counseling and testing centers. Future interventions, including delabeling the counseling and testing centers and demonstrating the efficacy of highly active antiretroviral therapy, will be critical in reducing the stigma of HIV/AIDS in communities. PMID:21149851

  16. Structural development and crustal stretching in the Muglad Basin, southern Sudan

    NASA Astrophysics Data System (ADS)

    Mohamed, A. Y.; Ashcroft, W. A.; Whiteman, A. J.

    2001-02-01

    A simplified model cross-section has been established from integrated well data, reflection seismic and gravity data along a northeast-southwest profile in the Unity-Kaikang area in the Muglad Basin, southern Sudan. A multi-layer crustal model has been created to produce a better estimate of the crustal extension involved and assess some of the key factors in the basin's formation by comparison to a theoretical model. Within the sedimentary section, three reflection seismic horizons were picked and their depths were calculated: Top Bentiu (Cenomanian), Top Abu Gabra (Aptian-Albian) and Top Basement (Late Jurassic-Early Cretaceous). The integrated well and seismic data indicate a sedimentary section up to 11 km thick along the cross-section. Different densities were assigned to the three sedimentary layers according to well data, and upper and lower crustal layers were incorporated in the model. Isostatic compensation of the sedimentary fill and the resultant crustal thinning was estimated by gravity modelling. The stretching of the lithosphere is estimated at ≈56 km (≈61%), corresponding to a β factor of 1.61. The form of the basin agrees with the model of a rift basin developed over an extended period of time.

  17. Prevalence of livestock diseases and their impact on livelihoods in Central Equatoria State, Southern Sudan.

    PubMed

    Malak, A K; Mpoke, L; Banak, J; Muriuki, S; Skilton, R A; Odongo, D; Sunter, J; Kiara, H

    2012-05-01

    A participatory epidemiological (PE) study was conducted in Kajo Keji and Yei Counties, Central Equatoria State, southern Sudan to assess the impact of livestock diseases on livelihoods. A serological survey of tick-borne diseases was conducted to supplement the PE study. PE data collection tools consisted primarily of focus group interviews and key informant interviews supplemented by observation. Information was collected on the social context, history and species of livestock kept. Constraints in livestock keeping were explored through description and probing. Proportional piling on the importance of different diseases and relative incidence scoring were also conducted. 243 sera were collected from cattle and tested for antibodies to Anaplasma marginale, Babesia bigemina, B. bovis, Theileria mutans and T. parva by ELISA. Additionally, 173 blood samples were collected for a PCR assay of T. parva. Livestock diseases were ranked as the most important constraint to livestock keeping. While East Coast fever was ranked as the most important disease in Kajo Keji, diarrhoea in small ruminants was reported as the most important disease in Yei. Serological analyses of the sera indicated that A. marginale, B. bigemina, T. mutans and T. parva were most prevalent. Prevalence of B. bovis was found to be low (4.0% and 7.4% in Kajo Keji and Yei, respectively). 35% of the samples screened with the T. parva p104 gene nested PCR assay were positive. The study concludes that while ECF is the most important disease in Kajo Keji, it was not the case in Yei. Additional epidemiological studies are proposed before control strategies are recommended. PMID:22244519

  18. They Own This: Mother Tongue Instruction for Indigenous Kuku Children in Southern Sudan

    ERIC Educational Resources Information Center

    Laguarda, Ana Isabel; Woodward, Walter Pierce

    2013-01-01

    This article details a pilot program of mother tongue instruction in five primary schools for classes one through three, in Kajokeji County, Central Equatoria State, South Sudan. The program was launched by teachers and volunteers with the support of the Jesuit Refugee Service, an international non-governmental organization. The research examines…

  19. The Research Process in a Multi-Level Mixed-Methods Case Study: International Organization Headquarters and Field Employee Perspectives of a Program in Southern Sudan

    ERIC Educational Resources Information Center

    Eschenbacher, Heidi

    2012-01-01

    This article provides an overview of the methods and data-collection process for a multi-level mixed-methods case study. Data for the study were gathered through phone interviews and electronic surveys from individuals working on the same educational program in Southern Sudan, though some were supporting the program from outside the country. The…

  20. Analysis of the Role of the Meridi Extension Unit in the Socio-Economic Development of Primitive Tribal Societies in Southern Sudan.

    ERIC Educational Resources Information Center

    Noah, Salah Eldin

    Review of anthropological studies on the Azandi tribe and nomadic tribal groups in southern Sudan, and collection of information through interviews and participant observation, provided the basis for a study of the functioning of and changes in tribal social organization and culture. The study is an attempt to investigate the way in which improved…

  1. Post-conflict mental health needs: a cross-sectional survey of trauma, depression and associated factors in Juba, Southern Sudan

    PubMed Central

    Roberts, Bayard; Damundu, Eliaba Yona; Lomoro, Olivia; Sondorp, Egbert

    2009-01-01

    Background The signing of the Comprehensive Peace Agreement in January 2005 marked the end of the civil conflict in Sudan lasting over 20 years. The conflict was characterised by widespread violence and large-scale forced migration. Mental health is recognised as a key public health issue for conflict-affected populations. Studies revealed high levels of post-traumatic stress disorder (PTSD) amongst populations from Southern Sudan during the conflict. However, no studies have been conducted on mental health in post-war Southern Sudan. The objective of this study was to measure PTSD and depression in the population in the town of Juba in Southern Sudan; and to investigate the association ofdemographic, displacement, and past and recent trauma exposure variables, on the outcomes of PTSD and depression. Methods A cross-sectional, random cluster survey with a sample of 1242 adults (aged over 18 years) was conducted in November 2007 in the town of Juba, the capital of Southern Sudan. Levels of exposure to traumatic events and PTSD were measured using the Harvard Trauma Questionnaire (original version), and levels of depression measured using the Hopkins Symptom Checklist-25. Multivariate logistic regression was used to analyse the association ofdemographic, displacement and trauma exposure variables on the outcomes of PTSD and depression. Multivariate logistic regression was also conducted to investigate which demographic and displacement variables were associated with exposure to traumatic events. Results Over one third (36%) of respondents met symptom criteria for PTSD and half (50%) of respondents met symptom criteria for depression. The multivariate logistic regression analysis showed strong associations of gender, marital status, forced displacement, and trauma exposure with outcomes of PTSD and depression. Men, IDPs, and refugees and persons displaced more than once were all significantly more likely to have experienced eight or more traumatic events. Conclusion

  2. 3 CFR - Presidential Determination on Sudan

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 3 The President 1 2011-01-01 2011-01-01 false Presidential Determination on Sudan Presidential... Presidential Determination on Sudan Memorandum for the Secretary of State President of the Export-Import Bank... related equipment that enables the United Nations to facilitate the referendum in Southern Sudan...

  3. Training rural health staff for oral rehydration therapy in southern Sudan.

    PubMed

    Hetta, O M; Lundstrøm, K J

    1984-10-01

    From February 1980 to August 1982 a very definite change occurred in the treatment pattern for diarrhoea among the rural health staff in Torit and Kapoeta districts in Eastern Equatoria Province in Sudan. This paper describes a training and supervision programme for promoting use of ORT in diarrhoeal diseases and at the same time discouraging the use of sulphonamides in simple diarrhoea. In the training programme emphasis is put on increasing the knowledge of the health staff both about the medical facts and about communication with their communities. ORS as treatment for diarrhoea has been well accepted by the public, who consider the sugar/salt solution as "good medicine". The use of sulphonamides for diarrhoea has decreased from 75% to 22% of the diarrhoea cases, while use of ORS has increased from 7% to 72% of the diarrhoea cases. PMID:6495369

  4. 31 CFR 538.320 - Specified Areas of Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Specified Areas of Sudan. 538.320 Section 538.320 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 538.320 Specified Areas of Sudan. (a) The term Specified Areas of Sudan means Southern...

  5. 31 CFR 538.320 - Specified Areas of Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Specified Areas of Sudan. 538.320 Section 538.320 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 538.320 Specified Areas of Sudan. (a) The term Specified Areas of Sudan means Southern...

  6. 31 CFR 538.320 - Specified Areas of Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Specified Areas of Sudan. 538.320 Section 538.320 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 538.320 Specified Areas of Sudan. (a) The term Specified Areas of Sudan means Southern...

  7. 31 CFR 538.320 - Specified Areas of Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Specified Areas of Sudan. 538.320 Section 538.320 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 538.320 Specified Areas of Sudan. (a) The term Specified Areas of Sudan means Southern...

  8. 31 CFR 538.320 - Specified Areas of Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Specified Areas of Sudan. 538.320 Section 538.320 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... Definitions § 538.320 Specified Areas of Sudan. (a) The term Specified Areas of Sudan means Southern...

  9. The Birth of a New Nation: The Republic of South Sudan

    ERIC Educational Resources Information Center

    Totten, Samuel

    2011-01-01

    In early July, the country of Sudan, wracked by civil war since the 1980s, officially split into two separate nations, Sudan and South Sudan. Six months earlier, over a seven-day period, the people in southern Sudan had voted in a national referendum on whether to secede from the North. The voters had two choices: "Separation" or "Unity." For the…

  10. The influence of demographic characteristics, living conditions, and trauma exposure on the overall health of a conflict-affected population in Southern Sudan

    PubMed Central

    2010-01-01

    Background There remains limited evidence on how armed conflict affects overall physical and mental well-being rather than specific physical or mental health conditions. The aim of this study was to investigate the influence of demographic characteristics, living conditions, and violent and traumatic events on general physical and mental health in Southern Sudan which is emerging from 20 years of armed conflict. Methods A cross-sectional survey of 1228 adults was conducted in November 2007 in the town of Juba, the capital of Southern Sudan. Multivariate linear regression analysis was used to investigate the associations and relative influence of variables in three models of demographic characteristics, living conditions, and trauma exposure, on general physical and mental health status. These models were run separately and also as a combined model. Data quality and the internal consistency of the health status instrument (SF-8) were assessed. Results The variables in the multivariate analysis (combined model) with negative coefficients of association with general physical health and mental health (i.e. worse health), respectively, were being female (coef. -2.47; -2.63), higher age (coef.-0.16; -0.17), absence of soap in the household (physical health coef. -2.24), and experiencing within the past 12 months a lack of food and/or water (coef. -1.46; -2.27) and lack of medical care (coef.-3.51; -3.17). A number of trauma variables and cumulative exposure to trauma showed an association with physical and mental health (see main text for data). There was limited variance in results when each of the three models were run separately and when they were combined, suggesting the pervasive influence of these variables. The SF-8 showed good data quality and internal consistency. Conclusions This study provides evidence on the pervasive influence of demographic characteristics, living conditions, and violent and traumatic events on the general physical and mental health of a

  11. High prevalence of hypertension among an ethnic group in Sudan: implications for prevention.

    PubMed

    Noor, Sufian K; Elsugud, Nada A; Bushara, Sarra O; Elmadhoun, Wadie M; Ahmed, Mohamed H

    2016-04-01

    Objective Hypertension is an emerging non-communicable disease in developing countries. Due to its silent nature and serious complications, active screening is essential in order to prevent complications. For instance, premature mortality from cardiovascular diseases could be prevented by the effective control of hypertension. The aim of this study was to determine the prevalence of undiagnosed hypertension among Nuba ethnic group living in Atbara city, north Sudan and to identify the associated risk factors. Subject and methods All consenting 500 adults from Nuba tribe who live in El Wihda District, Atbara were included. Blood pressure (BP) and body mass index were measured. Standard interviewing procedures were used to record medical history, socio-demographic data, and lifestyle characteristics. Results Among the 500 participants, females were 364 (72.8%) and males were 136 (27.2%). The overall prevalence of undiagnosed hypertension was 49.4% (30.8% stage 1 hypertension and 18.6% stage 2 hypertension). In addition, 41% of the population was having prehypertension. The significant risk factors for high BP were: male sex, age above 45 years, overweight, illiteracy, and alcohol consumption. Conclusion Undiagnosed high BP is very common among Nuba ethnic group; therefore, active screening and early management are recommended to prevent complications. PMID:26738696

  12. 75 FR 75865 - Presidential Determination on Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-07

    ... enables the United Nations to facilitate the referendum in Southern Sudan pursuant to the Comprehensive... in the Federal Register. (Presidential Sig.) THE WHITE HOUSE, Washington, November 19, 2010 [FR...

  13. Flood pulsing in the Sudd wetland: analysis of seasonal variations in 2 inundation and evapotranspiration in Southern Sudan

    USGS Publications Warehouse

    Senay, Gabriel B.; Rebelo, L-M.; McCartney, M.P.

    2012-01-01

    Located on the Bahr el Jebel in South Sudan, the Sudd is one of the largest floodplain wetlands in the world. Seasonal inundation drives the hydrologic, geomorphological, and ecological processes, and the annual flood pulse is essential to the functioning of the Sudd. Despite the importance of the flood pulse, various hydrological interventions are planned upstream of the Sudd to increase economic benefits and food security. These will not be without consequences, in particular for wetlands where the biological productivity, biodiversity, and human livelihoods are dependent on the flood pulse and both the costs and benefits need to be carefully evaluated. Many African countries still lack regional baseline information on the temporal extent, distribution, and characteristics of wetlands, making it hard to assess the consequences of development interventions. Because of political instability in Sudan and the inaccessible nature of the Sudd, recent measurements of flooding and seasonal dynamics are inadequate. Analyses of multitemporal and multisensor remote sensing datasets are presented in this paper, in order to investigate and characterize flood pulsing within the Sudd wetland over a 12-month period. Wetland area has been mapped along with dominant components of open water and flooded vegetation at five time periods over a single year. The total area of flooding (both rain and river fed) over the 12 months was 41 334 km2, with 9176 km2 of this constituting the permanent wetland. Mean annual total evaporation is shown to be higher and with narrower distribution of values from areas of open water (1718 mm) than from flooded vegetation (1641 mm). Although the exact figures require validation against ground-based measurements, the results highlight the relative differences in inundation patterns and evaporation across the Sudd.

  14. Spectral P-wave magnitudes, magnitude spectra and other source parameters for the 1990 southern Sudan and the 2005 Lake Tanganyika earthquakes

    NASA Astrophysics Data System (ADS)

    Moussa, Hesham Hussein Mohamed

    2008-10-01

    Teleseismic Broadband seismograms of P-waves from the May 1990 southern Sudan and the December, 2005 Lake Tanganyika earthquakes; the western branch of the East African Rift System at different azimuths have been investigated on the basis of magnitude spectra. The two earthquakes are the largest shocks in the East African Rift System and its extension in southern Sudan. Focal mechanism solutions along with geological evidences suggest that the first event represents a complex style of the deformation at the intersection of the northern branch of the western branch of the East African Rift and Aswa Shear Zone while the second one represents the current tensional stress on the East African Rift. The maximum average spectral magnitude for the first event is determined to be 6.79 at 4 s period compared to 6.33 at 4 s period for the second event. The other source parameters for the two earthquakes were also estimated. The first event had a seismic moment over fourth that of the second one. The two events are radiated from patches of faults having radii of 13.05 and 7.85 km, respectively. The average displacement and stress drop are estimated to be 0.56 m and 1.65 MPa for the first event and 0.43 m and 2.20 MPa for the second one. The source parameters that describe inhomogeneity of the fault are also determined from the magnitude spectra. These additional parameters are complexity, asperity radius, displacements across the asperity and ambient stress drop. Both events produce moderate rupture complexity. Compared to the second event, the first event is characterized by relatively higher complexity, a low average stress drop and a high ambient stress. A reasonable explanation for the variations in these parameters may suggest variation in the strength of the seismogenic fault which provides the relations between the different source parameters. The values of stress drops and the ambient stresses estimated for both events indicate that these earthquakes are of interplate

  15. Al Jazirah, Sudan

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Al Jazirah (also Gezira) is one of the 26 states of Sudan. The state lies between the Blue Nile and the White Nile in the east-central region of the country. It is a well populated area suitable for agriculture. The area was at the southern end of Nubia and little is known about its ancient history and only limited archaeological work has been conducted in this area. The region has benefited from the Gezira Scheme, a program to foster cotton farming begun in 1925. At that time the Sennar Dam and numerous irrigation canals were built. Al Jazirah became the Sudan's major agricultural region with more than 2.5 million acres (10,000 km) under cultivation. The initial development project was semi-private, but the government nationalized it in 1950. Cotton production increased in the 1970s but by the 1990s increased wheat production has supplanted a third of the land formerly seeded with cotton.

    The image was acquired December 25, 2006, covers an area of 56 x 36.4 km, and is located near 14.5 degrees north latitude, 33.1 degrees east longitude.

    The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  16. A climate trend analysis of Sudan

    USGS Publications Warehouse

    Funk, Christopher C.; Eilerts, Gary; Verdin, Jim; Rowland, Jim; Marshall, Michael

    2011-01-01

    Summer rains in western and southern Sudan have declined by 10-20 percent since the mid-1970s. Observed warming of more than 1 degree Celsius is equivalent to another 10-20 percent reduction in rainfall for crops. The warming and drying have impacted southern Darfur and areas around Juba. Rainfall declines west of Juba threaten southern Sudan's future food production prospects. In many cases, areas with changing climate are coincident with zones of substantial conflict, suggesting some degree of association; however, the contribution of climate change to these conflicts is not currently understood. Rapid population growth and the expansion of farming and pastoralism under a more variable climate regime could dramatically increase the number of at-risk people in Sudan over the next 20 years.

  17. Measuring turbidity, and indicator to evaluate drinkability of waters in Southern countries? Approaches from Burkina Faso, Sudan and Argentina case studies

    NASA Astrophysics Data System (ADS)

    Lavie, Emilie; Robert, Elodie

    2013-04-01

    The relationship between proportion of suspended solids, dissolved oxygen and bacteriology has long been proven (Brock, 1966; Lechevallier et al., 1985; Bustina and Levallois, 2003; Chang and Liao, 2012), bacteria need coarse elements to hang on and develop. However, water bacteriology analyses are difficult to implement in southern countries. They are expensive and require sterile equipment, transport in cold conditions and a nearby laboratory, which remains difficult in remote areas under these hot latitudes. Yet, simple measurement devices allow to know in a few minutes the water turbidity. Is turbidity an efficient tool to evaluate the drinkability of water when no bacteriological analyses are possible? The results proposed here are taken from three different studies whose purposes were to measure different physical, chemical and bacteriological parameters of water used for human and/or animal consumption. One of the finalities was to propose a method, at lower cost, to evaluate the drinkability of water for consumption. Four case studies were chosen: the basin of the Doubegue River in Burkina Faso is a rural area of a developing country, where drinking water is taken from the alluvial aquifer close to the surface. Furthermore, the laundry is washed and the children play in running streams. Major expansion of the cultivated lands since 1980s has brought important soils losses, thus a chronicle contamination of surface water with suspended solids (Robert, 2012). The Mendoza and Tunuyán Rivers Basins in Argentina, an emerging country, have snow-glaciar regimes with naturally turbid waters. They supply drinking water to two towns, Mendoza and Tunuyán cities, respectively 1 million and 40,000 inhabitants. However, these two streams -whose watersheds are common- do not present the same managements: the Mendoza River has been equipped with large hydraulic infrastructures, moving the turbid waters into clear and erosive ones (Lavie, 2009), while the Tunuyán River

  18. Seismotectonic implications of sand blows in the southern Mississippi Embayment

    USGS Publications Warehouse

    Cox, R.T.; Hill, A.A.; Larsen, D.; Holzer, T.; Forman, S.L.; Noce, T.; Gardner, C.; Morat, J.

    2007-01-01

    We explore seismically-induced sand blows from the southern Mississippi Embayment and their implications in resolving the question of near or distal epicentral source region. This was accomplished using aerial photography, field excavations, and cone penetration tests. Our analysis shows that three sand blow fields exhibit a distinct chronology of strong ground motion for the southern embayment: (1) The Ashley County, Arkansas sand blow field, near the Arkansas/Louisiana state border, experienced four Holocene sand venting episodes; (2) to the north, the Desha County field experienced at least three episodes of liquefaction; and (3) the Lincoln-Jefferson Counties field experienced at least one episode. Cone penetration tests (CPT) conducted in and between the sand blow fields suggest that the fields may not be distal liquefaction associated with New Madrid seismic zone earthquakes but rather are likely associated with strong earthquakes on local faults. This conclusion is consistent with the differences in timing of the southern embayment sand venting episodes and those in the New Madrid seismic zone. These results suggest that active tectonism and strong seismicity in intraplate North America may not be localized at isolated weak spots, but rather widespread on fault systems that are favorably oriented for slip in the contemporary stress field. ?? 2006 Elsevier B.V. All rights reserved.

  19. A regional reconnaissance on yellow fever in the Sudan

    PubMed Central

    Taylor, R. M.; Haseeb, M. A.; Work, T. H.

    1955-01-01

    Neutralization-tests with yellow fever virus performed on 666 human sera collected in the southern Sudan imply that yellow fever is still endemic south of the 10th parallel, in the south-west border of the Nuba Mountains, and in the plains west of the Nuba Mountains as far north as El Muglad. Similar tests on bloods from 110 primates revealed a high rate of immunity among both baboons (Papio sp.) (94%) and grivet monkeys (Cercopithecus aethiops) (77%), and a very low rate (1 in 56) among galagos (Galago senegalensis). It would therefore appear that, in contrast to the baboon and the grivet monkey, the galago is not significantly involved in the cycle of the virus. The epidemiological implications of these findings are discussed. PMID:14379007

  20. Filariasis in the Sudan

    PubMed Central

    Kirk, R.

    1957-01-01

    The author summarizes the available information on Loa loa, Acanthocheilonema perstans and Wuchereria bancrofti infections in the Sudan, with special reference to the prevalence and distribution of the vectors. PMID:13472413

  1. Nodding syndrome - South Sudan, 2011.

    PubMed

    2012-01-27

    In November 2010, the Ministry of Health of the proposed nation of South Sudan requested CDC assistance in investigating a recent increase and geographic clustering of an illness resulting in head nodding and seizures. The outbreak was suspected to be nodding syndrome, an unexplained neurologic condition characterized by episodes of repetitive dropping forward of the head, often accompanied by other seizure-like activity, such as convulsions or staring spells. The condition predominantly affects children aged 5-15 years and has been reported in South Sudan from the states of Western and Central Equatoria and in Northern Uganda and southern Tanzania. Because of visa and security concerns, CDC investigators did not travel to South Sudan until May 2011. On arrival, a case-control study was conducted that included collecting exposure information and biologic specimens to assess the association of nodding syndrome with suspected risk factors. A total of 38 matched case-control pairs were enrolled from two different communities: Maridi and Witto. Overall, current infection with Onchocerca volvulus diagnosed by skin snip was more prevalent among the 38 case-patients (76.3%) than the controls (47.4%) (matched odds ratio [mOR] = 3.2). This difference was driven by the 25 pairs in Maridi (88.0% among case-patients, 44.0% among controls, mOR=9.3); among the 13 pairs in Witto, no significant association with onchocerciasis (known as river blindness) was observed. Although onchocerciasis was more prevalent among case-patients, whether infection preceded or followed nodding syndrome onset was unknown. Priorities for nodding syndrome investigations include improving surveillance to monitor the number of cases and their geographic distribution and continued work to determine the etiology of the syndrome. PMID:22278159

  2. The Politics of Writing Tribal Identities in the Sudan: The Case of the Colonial Nuba Policy

    ERIC Educational Resources Information Center

    Abdelhay, Ashraf Kamal

    2010-01-01

    Linguistics is implicated in the colonial project of the invention of "self-contained" "racial" and "tribal units" in the Sudan. This paper has two objectives. First, to historicise the notions of "language" in the postcolonial discourse of language planning in the Sudan by reviewing one of the significant colonial policies: the colonial Nuba…

  3. UNICEF and the Sudan.

    ERIC Educational Resources Information Center

    United Nations Children's Fund, Nairobi (Kenya). Eastern Africa Regional Office.

    Coupled with poor infrastructure, vast distances, and harsh climatic conditions, the enormous physical obstacles in the Sudan (Africa's largest country) have combined to produce extremely serious problems for Sudanese children, who will soon constitute half of the 17 million people there. This booklet describes continuing projects implemented by…

  4. Demanding Divestment from Sudan

    ERIC Educational Resources Information Center

    Asquith, Christina

    2006-01-01

    Bowing to student demands to "stop supporting genocide," the University of California regents voted earlier this year to divest millions of dollars from companies working in the war-torn African nation of Sudan, the first major public university in the nation to take such action. Since student protests on the subject began at Harvard University in…

  5. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the Government of Sudan, persons in Sudan, or benefitting Sudan. 538.505 Section 538.505 Money and... Licensing Policy § 538.505 Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting Sudan. (a) The provision to the Government of Sudan, to a person in Sudan, or...

  6. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the Government of Sudan, persons in Sudan, or benefitting Sudan. 538.505 Section 538.505 Money and... Licensing Policy § 538.505 Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting Sudan. (a) The provision to the Government of Sudan, to a person in Sudan, or...

  7. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the Government of Sudan, persons in Sudan, or benefitting Sudan. 538.505 Section 538.505 Money and... Licensing Policy § 538.505 Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting Sudan. (a) The provision to the Government of Sudan, to a person in Sudan, or...

  8. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... the Government of Sudan, persons in Sudan, or benefitting Sudan. 538.505 Section 538.505 Money and... Licensing Policy § 538.505 Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting Sudan. (a) The provision to the Government of Sudan, to a person in Sudan, or...

  9. Seismic Hazard Implication of the Seismotectonics of southern Africa

    NASA Astrophysics Data System (ADS)

    Midzi, Vunganai; Mulabisana, Thifelimbilu; Manzunzu, Brassnavy

    2014-05-01

    The work presented in this report / presentation was prepared as part of the requirements for the SIDA/IGCP Project 601 titled "Seismotectonics and Seismic Hazards in Africa" as well as part of the seismic source characterisation of the GEM-Africa Seismic hazard study. An effort was made to compile information necessary to prepare a seismotectonic map of Africa which can then be used in carrying out a seismic hazard assessment of the continent or locations within the continent. Information on major faults, fault plane solutions, geophysical data as well as stress data has so far been collected and included in a database for the southern Africa region. Reports published by several experts contributed much to the collected information. The seismicity data used are part of the earthquake catalogue being prepared for the GEM-Africa project, which includes historical and instrumental records as collected from various sources. An effort has been made to characterise the identified major faults and through further analysis investigate their possible impact on the seismic hazard of southern Africa.

  10. Distance Teaching in the Sudan.

    ERIC Educational Resources Information Center

    Badri, Hagga Kashif

    1979-01-01

    Discusses the history, social climate, and country of Sudan as they relate to several educational projects. It is suggested that a satisfactory rate of development cannot be achieved while illiteracy remains at its present high level. (Author/JEG)

  11. Southern Hemisphere Storm Zones on Mars: Implications of MOLA Topography

    NASA Technical Reports Server (NTRS)

    Hollingsworth, J. L.; Haberle, R. M.; Schaeffer, J.

    1999-01-01

    Using the NASA Ames Mars general circulation model and recent Mars orbiter laser altimeter (MOLA) global topography, annual-cycle simulations have been performed corresponding to a lowglobally-averaged atmospheric dust loading (tau= 0 - 3). Comparisons of key global circulation fields as simulated utilizing previous topography datasets and those using the new Mars global topography have been carried out. Values of globally and/or hemispheric averaged kinetic energy associated with the longitudinally averaged (i.e., zonal) circulation and longitudinal departures (i.e., eddy components) as a function of season for simulations using the different topography datasets are provided contributions arising frommeteorological variability associated with thermal tides, stationary circulation components and recurrent weather systems (transient baroclinc and/or barotropic eddies). It can be noted that eddy activity in the northern hemisphere (NH) is substantially diminished using the new topographic data, and that at some seasons, the southern hemisphere (SH) activity is moderately increased. Additional information is contained in the original extended abstract.

  12. Petrogenesis and tectonic implications of the Yadong leucogranites, southern Himalaya

    NASA Astrophysics Data System (ADS)

    Gou, Zhengbin; Zhang, Zeming; Dong, Xin; Xiang, Hua; Ding, Huixia; Tian, Zuolin; Lei, Hengcong

    2016-07-01

    The leucogranites in the Higher Himalayan Sequence (HHS) provide a probe to elucidate the crustal melting of continental collisional orogen. An integrated geochemical and geochronological study of the Yadong leucogranites, southern Himalaya, shows that these rocks have relatively high SiO2 contents of 69.77 to 75.32 wt.% and alumina saturation index (A/CNK) of 1.09-1.40, typical of peraluminous granites. They show moderately fractionated REE patterns with negative Eu anomalies, and are characterized by enriched LILE (Rb and Cs) and depleted HFSE (Zr, Hf, Nb and Ta). LA-ICP-MS U-Pb zircon dating of ten samples yields crystallization ages ranging from 21.0 to 11.7 Ma. The zircons have variable εHf(t) values of - 26.3 to - 3.5 and corresponding Hf two-stage model ages of 2.77-1.33 Ga. The present study reveals that the muscovite-biotite leucogranites (2ML) have higher TiO2, MgO, CaO, Sr, Ba and Zr contents, lower Rb/Sr ratios than the tourmaline-muscovite leucogranites (TML). Zircon and monazite saturation thermometry results show that the melt temperatures (681-784 °C) of the 2ML are 20-80 °C higher than those (663-705 °C) of the TML. Combining with previous results, we propose that the TML were derived from the muscovite-dehydration melting, whereas the 2ML dominantly resulted from the biotite-dehydration melting during the prograde metamorphism of the pelitic and felsic granulites of the HHS. Therefore, the Himalayan leucogranites were probably formed during the subduction of the Indian crust following the India and Asia collision.

  13. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

    PubMed Central

    Ageep, Tellal B; Cox, Jonathan; Hassan, M'oawia M; Knols, Bart GJ; Benedict, Mark Q; Malcolm, Colin A; Babiker, Ahmed; El Sayed, Badria B

    2009-01-01

    Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM) that may include the sterile insect technique (SIT). To support the planning and implementation of future AW-IPM activities, larval surveys were carried out to provide key data on spatial and seasonal dynamics of local vector populations. Methods Monthly cross-sectional larval surveys were carried out between March 2005 and May 2007 in two localities (Dongola and Merowe) adjacent to the river Nile. A stratified random sampling strategy based on the use of Remote Sensing (RS), Geographical Information Systems (GIS) and the Global Positioning System (GPS) was used to select survey locations. Breeding sites were mapped using GPS and data on larval density and breeding site characteristics were recorded using handheld computers. Bivariate and multivariate logistic regression models were used to identify breeding site characteristics associated with increased risk of presence of larvae. Seasonal patterns in the proportion of breeding sites positive for larvae were compared visually to contemporaneous data on climate and river height. Results Of a total of 3,349 aquatic habitats sampled, 321 (9.6%) contained An. arabiensis larvae. The frequency with which larvae were found varied markedly by habitat type. Although most positive sites were associated with temporary standing water around the margins of the main Nile channel, larvae were also found at brickworks and in areas of leaking pipes and canals – often far from the river. Close to the Nile channel, a distinct seasonal pattern in larval populations was evident and appeared to be linked to the rise and fall of the river level. These patterns were not evident in vector

  14. Orbital Radar Response of Near Surface Materials in Southern Egypt and Implications for Cenozoic History

    NASA Astrophysics Data System (ADS)

    Maxwell, T. A.; Grant, J. A.; Johnston, A. K.

    2004-05-01

    Although the existence of "trunk" and tributary drainage channels beneath the sand in the northeast Sahara has been known for two decades, data from the SIR-C mission continues to be useful in solving geologic problems and understanding the radar response from specific types of near surface materials. In the Kiseiba Oasis region of southwest Egypt, SIR-C data revealed a complex tributary pattern of varying brightness that indicated the presence of paleodrainage not noted in the field. The orbital imaging radar uniquely specified key areas for detailed field studies that were not apparent in visible wavelengths. Twenty-two trenches up to 3 m deep, hundreds of shallow pits, several auger holes, and ground penetrating radar reveal that this area has had a history of fluctuating climatic conditions responsible for excavation and enlargement of the local depression by fluvial erosion and preservation of relict surfaces by aeolian blanketing of sand sheet deposits. The resulting near-surface stratigraphy is a complex mixture of fluvial pebble lags in the subsurface and on the surface, where aeolian mixing and local transport have modified the original geometry. In L-band (23 cm wavelength) SIR-C data, a hierarchy of returned signal strength and geometric patterns enables us to predict the type of surface and near-surface materials, sequentially from shallow bedrock to subsurface and surficial lags to sand sheet-veneered weathered anhydrite. Integrating the pattern of sedimentary deposits with relict channels and interfluves enables a better understanding of the origin of the Kiseiba-Dungul depression and its Cenozoic history. What was once thought to be a continuous deposit of Eocene limestone from southern Egypt into northern Sudan is cast in doubt as even the most optimistic estimates of scarp retreat don't permit hundred's of kms of retreat to the present position. Instead, the E-W pattern of the depression, the relict hills, and fracture zones all suggest structural

  15. Endemic treponematoses in the Sudan.

    PubMed

    Abu Ahmed Mohamed, H

    1985-01-01

    Sudan is surrounded by eight countries and has marked movement of population across its borders. At one time yaws and syphilis were important public health problems in the Sudan. Following the wide use of penicillin, both diseases were much reduced in prevalence and were no longer public health problems. However, the extensive population movement and particularly the huge influx of refugees across the border pose important potential hazards. The rapid urbanization and the social and cultural changes that followed economic development affected family ties and community behavior and resulted in a marked increase in the prevalence of sexually transmitted diseases, including syphilis. It is difficult to know the true magnitude of the problem because of the poor health information system and coverage. Improvement of the surveillance system is urgently needed, and more attention needs to be paid to treponemal infections. This entails improvement in health services and training of health personnel. PMID:4012164

  16. Agricultural fields, Khartoum, Sudan, Africa

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This herringbone pattern of irrigated agricultural fields near Khartoum, Sudan (14.5N, 33.5E) is very distinctive in both size and shape. The region contains thousands of these rectangular fields bounded by canals which carry water from both the White and Blue Nile Rivers. A crop rotation system is used so that some fields are in cotton, millit, sorghum or fallow to conserve moisture and control weeds and insects. See also STS049-96-003.

  17. Human Resources for Information Development in Sudan.

    ERIC Educational Resources Information Center

    Wesley, Cecile

    1992-01-01

    Describes the state of human resources development in Sudan's information industry. Training problems and the emigration of high level personnel are discussed, guidelines for human resource development are suggested, and national strategies to develop and retain Sudan's human resources are suggested. (EA)

  18. Language Situation in Post-War Sudan

    ERIC Educational Resources Information Center

    Siddiek, Ahmed Gumaa

    2010-01-01

    The theme behind this paper is to review the language policy and language planning in the Sudan, after the institutionalization of peace; by exploring the recent policy of political factions in the North and the South towards languages in post-war Sudan. This effort aims at encouraging non-Arabic speaking-ethnic-groups to accept the Arabic…

  19. 31 CFR 538.418 - Financial transactions in Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Financial transactions in Sudan. 538... Interpretations § 538.418 Financial transactions in Sudan. (a) Any financial transaction with a depository institution located in an area of Sudan other than the Specified Areas of Sudan, e.g., Khartoum,...

  20. 31 CFR 538.418 - Financial transactions in Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Financial transactions in Sudan. 538... Interpretations § 538.418 Financial transactions in Sudan. (a) Any financial transaction with a depository institution located in an area of Sudan other than the Specified Areas of Sudan, e.g., Khartoum,...

  1. 31 CFR 538.418 - Financial transactions in Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Financial transactions in Sudan. 538... Interpretations § 538.418 Financial transactions in Sudan. (a) Any financial transaction with a depository institution located in an area of Sudan other than the Specified Areas of Sudan, e.g., Khartoum,...

  2. 31 CFR 538.418 - Financial transactions in Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Financial transactions in Sudan. 538... Interpretations § 538.418 Financial transactions in Sudan. (a) Any financial transaction with a depository institution located in an area of Sudan other than the Specified Areas of Sudan, e.g., Khartoum,...

  3. 31 CFR 538.418 - Financial transactions in Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Financial transactions in Sudan. 538... Interpretations § 538.418 Financial transactions in Sudan. (a) Any financial transaction with a depository institution located in an area of Sudan other than the Specified Areas of Sudan, e.g., Khartoum,...

  4. Identification of two distinct fire regimes in Southern California: implications for economic impact and future change

    NASA Astrophysics Data System (ADS)

    Jin, Yufang; Goulden, Michael L.; Faivre, Nicolas; Veraverbeke, Sander; Sun, Fengpeng; Hall, Alex; Hand, Michael S.; Hook, Simon; Randerson, James T.

    2015-09-01

    The area burned by Southern California wildfires has increased in recent decades, with implications for human health, infrastructure, and ecosystem management. Meteorology and fuel structure are universally recognized controllers of wildfire, but their relative importance, and hence the efficacy of abatement and suppression efforts, remains controversial. Southern California’s wildfires can be partitioned by meteorology: fires typically occur either during Santa Ana winds (SA fires) in October through April, or warm and dry periods in June through September (non-SA fires). Previous work has not quantitatively distinguished between these fire regimes when assessing economic impacts or climate change influence. Here we separate five decades of fire perimeters into those coinciding with and without SA winds. The two fire types contributed almost equally to burned area, yet SA fires were responsible for 80% of cumulative 1990-2009 economic losses (3.1 Billion). The damage disparity was driven by fire characteristics: SA fires spread three times faster, occurred closer to urban areas, and burned into areas with greater housing values. Non-SA fires were comparatively more sensitive to age-dependent fuels, often occurred in higher elevation forests, lasted for extended periods, and accounted for 70% of total suppression costs. An improved distinction of fire type has implications for future projections and management. The area burned in non-SA fires is projected to increase 77% (±43%) by the mid-21st century with warmer and drier summers, and the SA area burned is projected to increase 64% (±76%), underscoring the need to evaluate the allocation and effectiveness of suppression investments.

  5. Environmental justice and regional inequality in southern California: implications for future research.

    PubMed

    Morello-Frosch, Rachel; Pastor, Manuel; Porras, Carlos; Sadd, James

    2002-04-01

    Environmental justice offers researchers new insights into the juncture of social inequality and public health and provides a framework for policy discussions on the impact of discrimination on the environmental health of diverse communities in the United States. Yet, causally linking the presence of potentially hazardous facilities or environmental pollution with adverse health effects is difficult, particularly in situations in which diverse populations are exposed to complex chemical mixtures. A community-academic research collaborative in southern California sought to address some of these methodological challenges by conducting environmental justice research that makes use of recent advances in air emissions inventories and air exposure modeling data. Results from several of our studies indicate that communities of color bear a disproportionate burden in the location of treatment, storage, and disposal facilities and Toxic Release Inventory facilities. Longitudinal analysis further suggests that facility siting in communities of color, not market-based "minority move-in," accounts for these disparities. The collaborative also investigated the health risk implications of outdoor air toxics exposures from mobile and stationary sources and found that race plays an explanatory role in predicting cancer risk distributions among populations in the region, even after controlling for other socioeconomic and demographic indicators. Although it is unclear whether study results from southern California can be meaningfully generalized to other regions in the United States, they do have implications for approaching future research in the realm of environmental justice. The authors propose a political economy and social inequality framework to guide future research that could better elucidate the origins of environmental inequality and reasons for its persistence. PMID:11929723

  6. An assessment of the feasibility for oil substitution in the Sudan

    SciTech Connect

    Perdikis, N.; Shibeika, M.H.E. )

    1989-01-01

    This paper attempts to assess the possibilities for oil substitution in the Sudan. The authors begin by analyzing the expected growth of energy demand between 1984 and 1990 basing their work on official reports and published statistics. They then turn to identifying the scope for oil use ratios at both the industry and industry subsector levels. The achieving of potential energy substitution is then examined in the light of available alternative technologies and fuel supplies. Finally they turn to discussing their findings' implications for public policy in the energy sector in the Sudan.

  7. Endemic treponematoses in the Sudan

    PubMed Central

    Grin, E. I.

    1961-01-01

    It has been recognized for many years that Africa contains a very large reservoir of endemic treponematoses, and all information on the foci of infection contributes to the goal of elimination of these diseases as public health problems. In 1959 the author undertook, at the request of the Sudanese Government, a number of pilot surveys in areas where the endemic treponematoses were thought to be prevalent. From the information acquired in these surveys and from official data it is clear that yaws and endemic syphilis are a major problem of public health in the Sudan. It is estimated that some 5 million people in six provinces are at risk, and that about 20% of the population in an area of 1 543 000 km2 suffer from one or the other of the two diseases in the active clinical stage. In some localities yaws was found to be prevalent, and in some endemic syphilis. In others, the two infections were seen to co-exist; and it is suggested that, since little is known of the extent to which one infection confers protection against the other, the situation in the Sudan provides a perhaps unique opportunity for scientific studies of the interrelationship of these two diseases and their possible relationship with venereal syphilis. Another interesting finding, worthy of further investigation, was that mucous lesions occurred only in areas where syphilis was present and not where yaws alone was prevalent. PMID:13708748

  8. Mycetoma in children in Sudan.

    PubMed

    Fahal, A H; Sabaa, A H Abu

    2010-02-01

    We report on 722 children with confirmed mycetoma seen at the Mycetoma Research Centre, Khartoum, Sudan during May 1991 to March 2009. There were 531 males (73.5%) and 191 females (26.5%) with an age range of 4-17 years (mean 13.7+/-2.9 years); most were students. The majority of patients were from Central and Western Sudan. The disease duration ranged between 6 months and 14 years (mean 2.27+/-2.12 years). Most of the patients had eumycetoma (79.1%). The clinical course was typical in the majority of the patients. Family history of mycetoma was reported in 15% of patients. The foot was affected most, followed by knee, hand, head and neck, chest wall and buttocks. In the foot, the metatarsal bones and calcaneum were affected most. Cytological and ultrasonic examinations of the lesions and histological examination of the surgical biopsies were the cornerstone in the diagnosis of mycetoma. Combined medical treatment and surgical excision was the standard treatment. Disease recurrence after surgical excision was reported in 17.9% of patients. The morbidity rate in this study was high, and it had led to high school dropout and many socioeconomic impacts on patients, families and community. Children with mycetoma need psychological support to identify and to treat their psychosocial problems. PMID:19716573

  9. Sudan challenges the sand dragon.

    PubMed

    Tinker, J

    1978-01-01

    Formerly productive areas have become wasteland as the desert advances in the Sudan. To understand how desertification is undermining the very survival of the Sahel, one ecosystem is reviewed in detail here: the gum arabic zone of Kordofan. After cotton, gum arabic is Sudan's largest export, worth from $14-26 million in recent years. In this zone the ecologically balanced cycle of gum gardens, fire, grain crops, and fallow is now breaking down; the 1968-1973 drought having in many areas delivered the final blow. Because of a growing population, the cultivation period is extended, and the soil becomes impoverished. Overgrazing in the fallow period, and the lopping of gum trees for firewood is producing a low return on the gum trees. Without this gum to harvest for cash, farmers must repeatedly replant their subsistence crops until the land becomes useless sand. The Sudanese have recognized the problem earlier than most, and a number of imaginative and practicable pilot projects are already in use: 1) waterpoint management; 2) construction of firebreaks; 3) land threatened by shifting dunes has been enclosed by stockproof fence and afforested with local trees; and 4) shelter belts have been planted around town perimeters where old gum tree stumps have started to sprout and the grass is reseeding itself. Out of these pilot projects, and with the advice of the U.N. Environment Program, the U.N. Development Program, and FAO, the Sudanese have developed a modest $26 million desert encroachment control and rehabilitation program (DECARP). PMID:12278008

  10. Shear wave velocity structure of the southern African upper mantle with implications for the uplift of southern Africa

    NASA Astrophysics Data System (ADS)

    Adams, Aubreya; Nyblade, Andrew

    2011-08-01

    Broad-band seismic data from the southern African seismic experiment and the AfricaArray network are used to investigate the seismic velocity structure of the upper mantle beneath southern Africa, and in particular beneath the Kaapvaal Craton. A two-plane approximation method that includes a finite frequency sensitivity kernel is employed to measure Rayleigh wave phase velocities, which are inverted to obtain a quasi-3-D shear wave velocity model of the upper mantle. We find phase velocities for the Kaapvaal Craton and surrounding mobile belts that are comparable to those reported by previous studies, and we find little evidence for variation from east to west across the Namaqua-Natal Belt, a region not well imaged in previous studies. A high-velocity upper-mantle lid is found beneath the Kaapvaal Craton and most of southern Africa. For the Kaapvaal Craton, the thickness of the lid (˜150-200 km) is consistent with the lid thicknesses reported in many previous studies. The cratonic lid is underlain by a ˜100-km thick low-velocity zone with a 3.9 per cent maximum velocity reduction. By comparing the velocity model to those published for other Archean cratons, we find few differences, and therefore conclude that there is little evidence in the shear wave velocity structure of the mantle to indicate that the southern African plateau is supported by an upper-mantle thermal anomaly.

  11. Agonistic behaviour in juvenile southern rock lobster, Jasusedwardsii (Decapoda, Palinuridae): implications for developing aquaculture.

    PubMed

    Carter, Chris G; Westbury, Heath; Crear, Bradley; Simon, Cedric; Thomas, Craig

    2014-01-01

    The Southern rock lobster, Jasusedwardsii, is a temperate species of spiny lobster with established well managed fisheries in Australia and New Zealand. It has also been under consideration as a species with aquaculture potential. Agonistic behaviour has important consequences under aquaculture conditions that encompass direct effects, such as damage or death of protagonists, and indirect effects on growth that relate to resource access, principally food and refuge. This study aimed to identify and characterize behaviours and to make a preliminary investigation of their occurrence under tank culture. Juvenile Jasusedwardsii were examined in a flow-through seawater system using a remote video camera system. Twenty-nine behaviours were divided into three sub-groups: aggressive (11), avoidance (6) and others (12). Aggressive behaviours included attacks, pushing, lifting, clasping and carrying an opponent. Avoidance behaviours included moving away in a backwards-, forwards- or side-stepping motion as well as with more vigorous tail flips. These behaviours were components of twelve behavioural groups that described contact, attack and displacement between individuals. Activity was crepuscular with two clear peaks, one in the morning and the other in the evening. The occurrence of behavioural groups was not different between the morning and evening. The frequency of aggressive behaviours was not affected by changes made to stocking density or access to food. The implications of agonistic behaviours are discussed further in relation to developing aquaculture. PMID:25561845

  12. 31 CFR 538.305 - Government of Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Government of Sudan, as well as any political subdivision, agency, or instrumentality thereof, including the Central Bank of Sudan; (2) Any entity owned or controlled by the foregoing; (3) Any person to the...

  13. Stratigraphic assessment of the Arcelia Teloloapan area, southern Mexico: implications for southern Mexico's post-Neocomian tectonic evolution

    NASA Astrophysics Data System (ADS)

    Cabral-Cano, E.; Lang, H. R.; Harrison, C. G. A.

    2000-10-01

    Stratigraphic assessment of the "Tierra Caliente Metamorphic Complex" (TCMC) between Arcelia and Teloloapan in southern Mexico, based on photo interpretation of Landsat Thematic Mapper images and field mapping at the 1:100,000 scale, tests different tectonic evolution scenarios that bear directly on the evolution of the southern North American plate margin. The regional geology, emphasizing the stratigraphy of a portion of the TCMC within the area between Arcelia and Teloloapan is presented. Stratigraphic relationships with units in adjacent areas are also described. The base of the stratigraphic section is a chlorite grade metamorphic sequence that includes the Taxco Schist, the Roca Verde Taxco Viejo Formation, and the Almoloya Phyllite Formation. These metamorphic units, as thick as 2.7 km, are covered disconformably by a sedimentary sequence, 2.9 km thick, composed of the Cretaceous marine Pochote, Morelos, and Mexcala Formations, as well as undifferentiated Tertiary continental red beds and volcanic rocks. The geology may be explained as the evolution of Mesozoic volcanic and sedimentary environments developed upon attenuated continental crust. Our results do not support accretion of the Guerrero terrane during Laramide (Late Cretaceous-Paleogene) time.

  14. 31 CFR 538.417 - Transshipments through Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Transshipments through Sudan. 538.417... § 538.417 Transshipments through Sudan. (a) The exportation or reexportation of goods, technology, or services to the Specified Areas of Sudan is exempt under § 538.212(g) only if such goods, technology,...

  15. 31 CFR 538.417 - Transshipments through Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Transshipments through Sudan. 538.417... § 538.417 Transshipments through Sudan. (a) The exportation or reexportation of goods, technology, or services to the Specified Areas of Sudan is exempt under § 538.212(g) only if such goods, technology,...

  16. 31 CFR 538.417 - Transshipments through Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Transshipments through Sudan. 538.417... § 538.417 Transshipments through Sudan. (a) The exportation or reexportation of goods, technology, or services to the Specified Areas of Sudan is exempt under § 538.212(g) only if such goods, technology,...

  17. 31 CFR 538.417 - Transshipments through Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Transshipments through Sudan. 538.417... § 538.417 Transshipments through Sudan. (a) The exportation or reexportation of goods, technology, or services to the Specified Areas of Sudan is exempt under § 538.212(g) only if such goods, technology,...

  18. 31 CFR 538.417 - Transshipments through Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Transshipments through Sudan. 538.417... § 538.417 Transshipments through Sudan. (a) The exportation or reexportation of goods, technology, or services to the Specified Areas of Sudan is exempt under § 538.212(g) only if such goods, technology,...

  19. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  20. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 2 2014-01-01 2014-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  1. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 2 2013-01-01 2013-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  2. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Anti-terrorism: Sudan. 742.10 Section...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT... ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  3. Political Implications of the Southern African Development Community Agenda on Educational Development in the Region.

    ERIC Educational Resources Information Center

    Nziramasanga, Caiphas T.

    This paper briefly describes the historical development of the Southern African Development Coordination Conference (SADCC) from its roots in 1980 and examines the work of the Southern African Development Community (SADC) today. The objectives of the SADCC are listed from the 1980 declaration and the achievement of those objectives are assessed.…

  4. Not just about sunburn--the ozone hole's profound effect on climate has significant implications for Southern Hemisphere ecosystems.

    PubMed

    Robinson, Sharon A; Erickson, David J

    2015-02-01

    Climate scientists have concluded that stratospheric ozone depletion has been a major driver of Southern Hemisphere climate processes since about 1980. The implications of these observed and modelled changes in climate are likely to be far more pervasive for both terrestrial and marine ecosystems than the increase in ultraviolet-B radiation due to ozone depletion; however, they have been largely overlooked in the biological literature. Here, we synthesize the current understanding of how ozone depletion has impacted Southern Hemisphere climate and highlight the relatively few documented impacts on terrestrial and marine ecosystems. Reviewing the climate literature, we present examples of how ozone depletion changes atmospheric and oceanic circulation, with an emphasis on how these alterations in the physical climate system affect Southern Hemisphere weather, especially over the summer season (December-February). These potentially include increased incidence of extreme events, resulting in costly floods, drought, wildfires and serious environmental damage. The ecosystem impacts documented so far include changes to growth rates of South American and New Zealand trees, decreased growth of Antarctic mosses and changing biodiversity in Antarctic lakes. The objective of this synthesis was to stimulate the ecological community to look beyond ultraviolet-B radiation when considering the impacts of ozone depletion. Such widespread changes in Southern Hemisphere climate are likely to have had as much or more impact on natural ecosystems and food production over the past few decades, than the increased ultraviolet radiation due to ozone depletion. PMID:25402975

  5. The question of Sudan: a hydroeconomic optimization model for the Sudanese Nile

    NASA Astrophysics Data System (ADS)

    Satti, S.; Zaitchik, B.; Siddiqui, S.

    2014-10-01

    The effects of development and the uncertainty of a changing climate in East Africa pose myriad challenges for water managers along the Blue Nile. Sudan's large irrigation potential, hydroelectric dams, and prime location within the basin mean that Sudan's water management decisions will have great social, economic and political implications within the region. At the same time, Sudan's water use options are constrained by tradeoffs between upstream irrigation developments and downstream hydropower facilities as well as by the country's commitments under existing or future transboundary water sharing agreements. Here, we present a model that can be applied to evaluate optimal allocation of surface water resources to irrigation and hydropower in the Sudanese portion of the Blue Nile. Hydrologic inputs are combined with agronomic and economic inputs to formulate an optimization model within the General Algebraic Modeling System (GAMS). A sensitivity analysis is performed by testing model response to a range of economic conditions and to changes in the volume and timing of hydrologic flows. Results indicate that changing hydroclimate inputs have the capacity to greatly influence the productivity of Sudan's water resources infrastructure. Results also show that the economically optimal volume of water consumption, and thus the importance of existing treaty constraints, is sensitive to the perceived value of agriculture relative to electricity as well as to changing hydrological conditions.

  6. The question of Sudan: a hydro-economic optimization model for the Sudanese Blue Nile

    NASA Astrophysics Data System (ADS)

    Satti, S.; Zaitchik, B.; Siddiqui, S.

    2015-05-01

    The effects of development and the uncertainty of a changing climate in eastern Africa pose myriad challenges for water managers along the Blue Nile. Sudan's large irrigation potential, hydroelectric dams, and prime location within the basin mean that Sudan's water management decisions will have great social, economic and political implications for the region. At the same time, Sudan's water use options are constrained by tradeoffs between upstream irrigation developments and downstream hydropower facilities as well as by the country's commitments under existing or future transboundary water sharing agreements. Here, we present a model that can be applied to evaluate optimal allocation of surface water resources to irrigation and hydropower in the Sudanese portion of the Blue Nile. Hydrologic inputs are combined with agronomic and economic inputs to formulate an optimization model within the General Algebraic Modeling System (GAMS). A sensitivity analysis is performed by testing model response to a range of economic conditions and to changes in the volume and timing of hydrologic flows. Results indicate that changing hydroclimate inputs have the capacity to greatly influence the productivity of Sudan's water resource infrastructure. Results also show that the economically optimal volume of water consumption, and thus the importance of existing treaty constraints, is sensitive to the perceived value of agriculture relative to electricity as well as to changing hydrological conditions.

  7. Avalonian crustal controls on basin evolution: implications for the Mesozoic basins of the southern North Sea

    NASA Astrophysics Data System (ADS)

    Smit, Jeroen; van Wees, Jan-Diederik; Cloetingh, Sierd

    2015-04-01

    Little is known of the Southern North Sea Basin's (SNSB) Pre-Permian basement due to a lack of outcrop and cores. The nature and structure of the East Avalonian crust and lithosphere remain even less constrained in the absence of deep seismic (refraction) lines. However, various studies have hinted at the importance of the Reactivation of the Early Carboniferous fault network during each consecutive Mesozoic and Cenozoic tectonic phase, demonstrating the key role of weak zones from the Early Carboniferous structural grain in partitioning of structural deformation and vertical basin motions at various scales. Although the older basin history and the basement attract increasing attention, the Pre-Permian tectonics of the SNSB remains little studied with most attention focused on the Permian and younger history. The strong dispersal of existing constraints requires a comprehensive study from Denmark to the UK, i.e. the East Avalonian microplate, bordered by the Variscan Rheïc suture, the Atlantic and Baltica. Based on an extensive literature study and the reinterpretation of publicly available data, linking constraints from the crust and mantle to stratigraphic-sedimentological information, we complement the map of Early Carboniferous rifting of East Avalonia and propose a new tectonic scenario. From the reinterpretation of the boundary between Avalonia and Baltica we propose a new outline for the Avalonian microplate with implications for the tectonics of the North German Basin. Furthermore, we highlight the nature and extent of the major crustal/lithospheric domains with contrasting structural behaviour and the major boundaries that separate them. Results shed light on the effects of long lived differences in crustal fabric that are responsible for spatial heterogeneity in stress and strain magnitudes and zonations of fracturing, burial history and temperature history. The geomechanical control of large crustal-scale fault structures will provide the constraints

  8. The ethnic distribution of sickle cell disease in Sudan.

    PubMed

    Sabahelzain, Majdi Mohammed; Hamamy, Hanan

    2014-01-01

    Sickle cell disease (SCD) is one of the most common inherited disorders of haemoglobin in Africa and it is expected that sickle cell trait varies in frequency in different areas in Sudan. An extensive literature search was carried out accessing the US National Library of Medicine, the WHO Eastern Mediterranean Region resources, the Catalogue for Transmission Genetics in Arabs and papers and documents published in Sudan that included data on the prevalence of sickle cell anaemia and trait. Rates of SCA and trait varied in different areas in Sudan with the highest rates reported from Western and Eastern Sudan where one in every 123 children born in Messeryia tribe in Western Sudan is at risk of having SCD. High consanguinity rates and malaria endemicity are strong related factors with sickle cell gene in Sudan. This review will present what is known about the rates of sickle cell gene in different ethnic groups in Sudan. PMID:25360197

  9. The ethnic distribution of sickle cell disease in Sudan

    PubMed Central

    Sabahelzain, Majdi Mohammed; Hamamy, Hanan

    2014-01-01

    Sickle cell disease (SCD) is one of the most common inherited disorders of haemoglobin in Africa and it is expected that sickle cell trait varies in frequency in different areas in Sudan. An extensive literature search was carried out accessing the US National Library of Medicine, the WHO Eastern Mediterranean Region resources, the Catalogue for Transmission Genetics in Arabs and papers and documents published in Sudan that included data on the prevalence of sickle cell anaemia and trait. Rates of SCA and trait varied in different areas in Sudan with the highest rates reported from Western and Eastern Sudan where one in every 123 children born in Messeryia tribe in Western Sudan is at risk of having SCD. High consanguinity rates and malaria endemicity are strong related factors with sickle cell gene in Sudan. This review will present what is known about the rates of sickle cell gene in different ethnic groups in Sudan. PMID:25360197

  10. Aetiology of Oral Cancer in the Sudan

    PubMed Central

    2013-01-01

    ABSTRACT Objectives To review the studied risk factors that linked to aetiology of oral cancer in the Sudan. There have been numerous reports in the increase in the incidence of oral cancer from various parts of the world. A recent trend for a rising incidence of oral cancer, with the absence of the well established risk factors, has raised concern. Although, there are inconsistent data on incidence and demographical factors, studies suggest that the physiologic response to risk factors by men and women vary in different populations. Material and Methods This review principally examines 33 publications devoted to aetiology of oral cancer in the Sudan, in addition to some risk factors that are commonly practiced in the Sudan. Results Several studies examining risk factors for oral cancer include tobacco use (Smoked and Smokeless), alcohol consumption, occupational risk, familial risk, immune deficits, virus infection and genetic factors. Conclusions Toombak use and infection with high risk Human Papilloma Virus (HPV) were extensively investigated and linked to the aetiology of oral cancer in Sudan. PMID:24422031

  11. Sudan dyes: are they dangerous for human health?

    PubMed

    Fonovich, Teresa M

    2013-07-01

    Azo and diazo compounds include Sudan dyes, which were widely used in industry. Although they are not permitted in food, they had been found contaminating different food products and their presence is investigated regularly (since 2003) in these products. Sudan III, as well as Sudan Black B, was included in different laboratory techniques for tissue ceroid and lipofucsin analysis and blood-cell staining. Also, Sudan Black B has been recently included in in vivo evaluations in human beings (through oral intake), and Sudan III is still allowed in cosmetics. These azo dyes were metabolized to possible carcinogenic colorless amines, both in the liver of mammalians and by the micro flora present in human skin and the gastrointestinal tract. Both human and laboratory animal cytochrome P450s (CYPs) were able to oxidize Sudan I, whereas Sudan III modified CYP activities. In vitro genotoxic effects were reported for Sudan I, and some DNA adducts formed through exposure to its metabolites were identified. Sudan I was also found to be carcinogenic in the rat, but not in the mouse. The aim of the present review is to put together the most relevant information concerning Sudan dye uses and toxicity to provide some tools for the identification of the risk they represent for human health. PMID:22947042

  12. The emerging European immigration regime: some reflections on implications for southern Europe.

    PubMed

    Baldwin-edwards, M

    1997-12-01

    "Immigration is one of the more controversial areas in the history of European integration. Whilst northern European countries have been constructing elaborate compromises in the European Union (EU) Treaties and in the Schengen group, southern European countries have been trying to construct their own immigration policies. Little attention has been paid in the literature to the relationship between these two phenomena: it is suggested here that southern countries have found it expedient to fit in with EU and Schengen arrangements, even though these appear impossible to implement. This contradiction is seen as intrinsic to the overall relations of Portugal, Spain, Italy and Greece to the EU." PMID:12293846

  13. Tectonic implications of the microearthquake seismicity and fault plane solutions in southern Peru

    NASA Technical Reports Server (NTRS)

    Grange, F.; Hatzfeld, D.; Cunningham, P.; Molnar, P.; Roecker, S. W.; Suarez, G.; Rodrigues, A.; Ocola, L.

    1984-01-01

    Because the contortion in the seismic zone in southern Peru is aligned approximately parallel to the direction of relative plate motion, rather than perpendicular to the coast of Peru, the position of the contortion need not migrate with respect to the overriding South American plate as the Nazca plate subducts beneath it, and the flow in the surrounding asthenosphere could be in a steady state. In addition, the position of the contortion defines the northern boundary of the volcanic arc in southern Peru. The inference that a wedge of asthenospheric material must overlie the downgoing slab for subduction-related volcanism to occur is thereby strengthened.

  14. Revisiting atmospheric dust export to the Southern Hemisphere ocean: Biogeochemical implications

    NASA Astrophysics Data System (ADS)

    Wagener, Thibaut; Guieu, CéCile; Losno, RéMi; Bonnet, Sophie; Mahowald, Natalie

    2008-06-01

    Aerosol concentrations in the Southern Hemisphere are largely undersampled. This study presents a chemical and physical description of dust particles collected on board research vessels in the southeast Pacific (SEPS) and the Southern Ocean (SOKS). Concentrations of dust were 6.1 ± 2.4 ng m-3 for SEPS and 13.0 ± 6.3 ng m-3 for SOKS. Dust fluxes, derived from those concentrations, were 9.9 ± 3.7 μg m-2 d-1 for SEPS and 38 ± 14 μg m-2 d-1 for SOKS and are shown to be representative of actual fluxes in those areas. Dust and iron deposition are up to 2 orders of magnitude lower than former predictions. A map of dust deposition on the Southern Hemisphere is proposed by incorporating those in situ measurements into a dust model. This study confirms that dust deposition is not the dominant source of iron to the large high-nutrient low-chlorophyll Southern Ocean.

  15. Dissertation Citations in Organismal Biology at Southern Illinois University at Carbondale: Implications for Collection Development

    ERIC Educational Resources Information Center

    Nabe, Jonathan; Imre, Andrea

    2008-01-01

    We report on a citation analysis of Ph.D. dissertations in plant biology and zoology at Southern Illinois University Carbondale, undertaken to test the common assumption that scientists favor current research to such an extent that journal backfiles can be de-emphasized in academic library collections. Results demonstrate otherwise. The study is…

  16. Rehabilitation of the expanded programme on immunization in Sudan following a poliomyelitis outbreak.

    PubMed Central

    ElZein, H. A.; Birmingham, M. E.; Karrar, Z. A.; Elhassan, A. A.; Omer, A.

    1998-01-01

    In 1993 a large outbreak of paralytic poliomyelitis occurred in Sudan as a result of an accumulation of large numbers of susceptible children that was accelerated by faltering immunization services. The extent of the outbreak led to the rapid rehabilitation of Sudan's Expanded Programme on Immunization (EPI); the government began financing vaccine purchase, operational aspects of EPI were decentralized, vaccine delivery was changed from a mobile to a fixed-site strategy, a solar cold chain network was installed, inservice training was resuscitated, and social mobilization was enhanced. National immunization days (NIDs) for poliomyelitis eradication were conducted throughout the country, including the southern states during a cease fire in areas of conflict. Measles immunization coverage was increased by offering measles vaccine during the second round of NIDs and subsequently through routine immunization services. Supplemental tetanus toxoid immunization of women of child-bearing age began in three provinces at high risk for neonatal tetanus. From 1994 to 1996 reported immunization coverage increased and the incidence of all EPI target diseases fell. Trends in coverage, disease incidence, financing, and the implementation of WHO-recommended disease-control strategies suggest that more sustainable immunization services have been re-established in Sudan. PMID:9803584

  17. Present-day shortening in Southern Haiti from GPS measurements and implications for seismic hazard

    NASA Astrophysics Data System (ADS)

    Symithe, Steeve; Calais, Eric

    2016-06-01

    The ~ 3 M inhabitant capital region of Haiti, severely affected by the devastating January 12, 2010, M7.0 earthquake, continues to expand at a fast rate. Accurate characterization of regional earthquake sources is key to inform urban development and construction practices through improved regional seismic hazard estimates. Here we use a recently updated Global Positioning System (GPS) data set to show that seismogenic strain accumulation in southern Haiti involves an overlooked component of shortening on a south-dipping reverse fault along the southern edge of the Cul-de-Sac basin, in addition to the well-known component of left-lateral strike-slip motion. This tectonic model implies that ground shaking may be twice that expected if the major fault was purely strike-slip, as assumed in the current seismic hazard map for the region.

  18. Age and origin of cold climate landforms from the Eastern Cape Drakensberg, southern Africa: palaeoclimatic implications

    NASA Astrophysics Data System (ADS)

    Mills, Stephanie C.; Barrows, Timothy T.; Fifield, L. Keith

    2014-05-01

    Reliable dating is crucial for resolving the nature and timing of cold events in southern Africa and the associated cold climate landforms produced. Evidence for glaciation has been proposed for the Eastern Cape Drakensberg, based on the identification of moraines that were presumed to be of last glacial maximum age. Temperature depressions of 10-17°C have been proposed for this region, based on the presence of these moraines (Lewis and Illgner, 2001) and the identification of a relict rock glacier. Such large temperature depressions are, however, unsupported by other palaeoclimatic proxies in southern Africa. Debate regarding the occurrence of glaciation in southern Africa has been ongoing for several decades. There is good evidence for small-scale glaciation during the last glacial cycle in Lesotho, at elevations exceeding 3000 m a.s.l., but these sites are more than 1000 m higher in elevation than those identified in the Eastern Cape, and suggest a temperature depression of only ~6°C and a change to a winter dominated precipitation regime during the last glacial cycle. This paper presents preliminary cosmogenic nuclide exposure ages for the Eastern Cape 'moraines' and a periglacial blockstream in this region. We discuss potential alternative interpretations for the formation of the landforms and suggest that glaciers were absent in the Eastern Cape Drakensberg during the last glacial period. However, there is widespread evidence for periglacial activity down to an elevation of ~1700 m a.s.l., as illustrated by extensive blockstreams, stone garlands and solifluction deposits. These periglacial deposits suggest that the climate was much colder (~6ºC) during the last glacial cycle, in keeping with other proxy records, but not cold enough to initiate or sustain glaciers at low elevations. References Lewis C. A., Illgner, P. M., 2001. Late Quaternary glaciation in Southern Africa: moraine ridges and glacial deposits at Mount Enterprise in the Drakensberg of the

  19. Glacial-interglacial variability in diatom abundance and valve size: Implications for Southern Ocean paleoceanography

    NASA Astrophysics Data System (ADS)

    Nair, Abhilash; Mohan, Rahul; Manoj, M. C.; Thamban, Meloth

    2015-10-01

    Antarctic sea ice extent along with Southern Ocean biological productivity varied considerably during glacial-interglacial periods, and both are known to have played a considerable role in regulating atmospheric CO2 variations in the past. Here we present data on diatom absolute abundance (valves/g of sediment) and size over the past ~ 42 ka B.P. and how they link to glacial-interglacial changes in Antarctic sea ice extent, Southern Ocean frontal systems, and aeolian dust flux. Our records of sea ice and permanent open ocean zone diatom abundances suggest a shift in the Antarctic winter sea ice limit and Polar Front respectively up to the modern-day Polar Frontal Zone during marine isotopic stages (MIS) 2 and late MIS 3. In addition to glacial shifts in the Polar Front, diatom assemblages also recorded a plausible northward shifts in Polar Front during few intervals of MIS 1. Glacial periods north of the Polar Front in the Indian sector of the Southern Ocean were characterized by higher total diatom abundance, larger Fragilariopsis kerguelensis apical length, and Thalassiosira lentiginosa radius. This is probably a consequence of (1) a northward expansion of the opal belt, a region characterized by high production and export of biogenic silica; (2) an increase in terrigenous input, via erosion of Crozet Islands; and (3) the alleviation of iron deficit by high input of Fe-bearing dust. The larger and highly silicified diatoms such as F. kerguelensis and T. lentiginosa may have mainly contributed in transporting biogenic silica and organic carbon to the seabed for the last 42 ka, in the northern Polar Frontal Zone of the Indian sector of the Southern Ocean.

  20. Forest to agriculture conversion in southern Belize: Implications for migrant land birds

    USGS Publications Warehouse

    Spruce, J.P.; Dowell, B.A.; Robbins, C.S.; Sader, S.A.

    1993-01-01

    Central America offers a suite of neotropical habitats vital to overwintering migrant land birds. The recent decline of many forest dwelling avian migrants is believed to be related in part to neotropical deforestation and land use change. However, spatio-temporal trends in neotropical habitat availability and avian migrant habitat use are largely unknown. Such information is needed to assess the impact of agriculture conversion on migrant land birds. In response, the USDI Fish and Wildlife Service and the University of Maine began a cooperative study in 1988 which applies remote sensing and field surveys to determine current habitat availability and avian migrant habitat use. Study sites include areas in Belize, Costa Rica, Guatemala and southern Mexico. Visual assessment of Landsat TM imagery indicates southern Belize forests are fragmented by various agricultural systems. Shifting agriculture is predominant in some areas, while permanent agriculture (citrus and mixed animal crops) is the primary system in others. This poster focuses on efforts to monitor forest to agriculture conversion in southern Belize using remote sensing, field surveys and GIS techniques. Procedures and avian migrant use of habitat are summarized.

  1. Density variations between the southern and northern hemisphere of Mars: Implications from gravimetric inversion

    NASA Astrophysics Data System (ADS)

    Breuer, D.; Pauer, M.

    2008-12-01

    One remarkable feature of Mars is the crustal dichotomy which divides the surface into an old southern highland hemisphere rising several kilometers above the zero level and a superficially younger northern lowlands hemisphere well below the datum. Whether this crustal dichotomy is also reflected in composition, density, and thickness is not known -- although, a crustal thickness variation is generally suggested based on the assumption of a constant crustal density. We used gravimetric methods to place constraints on the maximum crustal density of the southern highlands. Gravimetric methods are ambiguous with a noted trade- off between the crustal thickness and density. However, combining two different methods, the geoid- topography ratio and Bouguer inversion, helps to constrain a maximum density of the crust for regions that show a homogeneous unit with respect to lateral density variations and compensation state. For the Martian Noachian southern highlands a combination of these methods suggests a maximum crustal density of 3020 ± 70 kgm-3, assuming a single-layer crustal structure. Two-layer crustal structures show similar results: the upper crustal density is also limited to ~ 3000 kgm-3, but a denser uniformly thick lower crust is possible. The obtained results together with the findings on crustal densities (and composition) of other regions on Mars are consistent with various scenarios of crustal evolution: 1) A 'temporal' evolution in the densities with low densities of the ancient crust and comparatively higher densities of the young (Amazonian-era) volcanic material. Such a 'temporal' increase may result from different formation mechanisms or possibly from a change in composition of the basaltic magmas over time. 2) The density variation is already manifested in the early evolution during the formation of the crustal dichotomy, i.e. the Noachian crust of the northern lowlands has a different density than the Noachian southern highland crust. The ancient

  2. Fore-arc Counterclockwise Rotation In Southern Mexico: Implications For The NA-CA-CO Triple Junction

    NASA Astrophysics Data System (ADS)

    Andreani, L.; Le Pichon, X.; Rangin, C.; Martinez-Reyes, J.

    2007-12-01

    Numerous studies, mainly based on structural and paleomagnetic data, consider the Southern Mexico as a crustal block (Southern Mexico Block, SMB) uncoupled from the North American plate with a southeast motion with respect to North America accommodated by extension through the central Trans-Mexican Volcanic Belt (TMVB). On the other hand, the accommodation of this motion on the southeastward boundary, especially at the Cocos/Caribbean/North American triple junction is still debated. The boundary between the SMB and the North American plate is constituted by three connected zones of deformation: (1) left-lateral transtension across the central TMVB, (2) left-lateral strike-slip faulting along the eastern TMVB and Veracruz area and (3) reverse and left- lateral strike-slip faulting in the Chiapas area. We show that these three active deformation zones accommodate a couterclockwise rotation of the SMB with respect to the North American plate. We specially discuss the Quaternary motion of the SMB with respect to the surrounding plates near the Cocos/Caribbean/North American triple junction. The model we propose predicts a Quaternary couterclockwise rotation of 0.45 deg/Ma with a pole located at 24.2N and 91.8W. Finally we discuss the geodynamic implications of this counterclockwise rotation. The Southern Mexico Block motion is generally assumed to be the result of slip partitioning at the trench. However the obliquity of the subduction is too small to explain slip partitioning. The motion could be facilitated by the high thermal gradient and gravitational collapse that affects central Mexico or by partial coupling with the eastward motion of the Caribbean plate.

  3. Lagrangian tracing of Sahelian Sudan moisture sources

    NASA Astrophysics Data System (ADS)

    Salih, Abubakr A. M.; Zhang, Qiong; Tjernström, Michael

    2015-07-01

    The Sahelian Sudan is an arid to semiarid region that depends on the seasonal rainfall as the main source of water, but its rainfall has large interannual variability. Such dry regions usually have their main moisture sources elsewhere; thus, the rainfall variability is directly related to the moisture transport. This study seeks to identify source regions of water vapor for Sahelian Sudan during the monsoon period, from July to September. We have used the Lagrangian trajectory model FLEXPART driven by ERA-Interim reanalysis for the time period 1998 to 2008. The results show that most of the air masses that reach this region during the monsoon period have their major origins over the Arabian Peninsula, Central Africa, or are associated with the tropical easterly jet. Flow associated with Intertropical Convergence Zone contributes almost half of the total precipitated water; most of it comes from Central Africa. This suggests that moisture recycling is the major contributor, compared to Oceanic sources. The flows from the northeast (Arabian Peninsula and north Asia) and east (Horn of Africa and north Indian Ocean) contribute about one third of the precipitated water. The rest of precipitated water comes from the Mediterranean, subtropical Atlantic, and western Sahel, all with smaller contribution. Our results also indicate that different subregions of Sahelian Sudan have different moisture sources. Such result needs to be taken into account in seasonal forecasting practices.

  4. Compositional heterogeneity of Asteroid 4 Vesta’s southern hemisphere: Implications for the Dawn mission

    NASA Astrophysics Data System (ADS)

    Reddy, Vishnu; Gaffey, Michael J.; Kelley, Michael S.; Nathues, Andreas; Li, Jian-Yang; Yarbrough, Robert

    2010-12-01

    High signal-to-noise, rotationally-resolved spectra of Asteroid 4 Vesta's southern hemisphere from the 2007 opposition were used to constrain its compositional and mineralogical variations. The spectra were rotationally-phased using closely timed HST observations of Vesta by Li et al. (Li, J.-Y., McFadden, L.A., Thomas, P.C., Mutchler, M.J., Parker, J.Wm., Young, E.F., Russell, C.T., Sykes, M.V., Schmidt, B.E. [2010]. Icarus 208, 238-251). The average surface of Vesta's southern hemisphere is analogous to a howardite or polymict eucrite assemblage similar to the northern hemisphere, although the band parameters are distinctly shifted towards the diogenite zone on the Band-Band plot. A few distinct compositional units were detected and they might be related to albedo features detected by Hubble Space Telescope (Li et al., 2010). We have identified two compositionally distinct regions overlaying the background surface. The first unit is a polymict eucrite and/or low-Ca eucrite compositional unit at 143° longitude that border the eucrite zone on the Band-Band plot and the second is a diogenite unit at 159°. While we did not detect any distinct olivine units as suggested by Gaffey (Gaffey, M.J. [1997]. Icarus 127, 130-157), we cannot rule out the possibility of smaller olivine-rich units that are below the detection limit of the instrumentation we used. Based on the analysis and the limitations of the data, we do not suggest that Vesta's surface is olivine-free. Mean pyroxene chemistry estimates for both hemispheres broadly agree with one another (to within one-sigma) with the northern hemisphere ferrosilite (Fs) and wollastonite (Wo) values being slightly higher than southern hemisphere.

  5. Southern dispersal and Palaeoecological implications of woolly rhinoceros ( Coelodonta antiquitatis): review of the Iberian occurrences

    NASA Astrophysics Data System (ADS)

    Álvarez-Lao, Diego J.; García, Nuria

    2011-07-01

    Cold-adapted large mammal populations spread southward during the coldest and driest phases of the Late Pleistocene reaching the Iberian Peninsula. Presence of woolly rhinoceros ( Coelodonta antiquitatis) can be identified from 23 Iberian sites, which is compiled and analyzed herein, and the fossil specimens from seven of these sites are described here for first time. Morphological and biometrical analyses demonstrate that the Iberian woolly rhinoceros did not significantly differ from individuals of other European populations, but represent the westernmost part of a continuous Eurasian belt of distribution. The first presence of woolly rhino in the Iberian Peninsula has been identified during the late Middle Pleistocene and early Late Pleistocene. However, the highest abundance of this species is recorded during MIS 3 and 2. The latest Iberian occurrences can be dated around 20 ka BP. The presence of woolly rhinoceros in the Iberian Peninsula correlates with periods of extreme dry and cold climatic conditions documented in Iberian terrestrial and marine sediment sequences. From a palaeobiogeographic point of view, the maximum southern spread of C. antiquitatis on the Iberian Peninsula was registered during the late Middle Pleistocene or early Late Pleistocene, reaching the latitude of Madrid (about 40°N). Subsequently, during MIS 3 and 2, all Iberian finds were restricted to the Northern regions of Iberia (Cantabrian area and Catalonia). The southern expansion of C. antiquitatis during the Late Pleistocene in the Iberian Peninsula reached similar latitudes to other Eurasian regions. The ecological composition of fossil assemblages with presence of woolly rhinoceros was statistically analyzed. Results show that temperate ungulate species are predominant at Iberian assemblages, resulting in a particular mixture of temperate and cold elements different of the typical Eurasian cold-adapted faunal associations. This particular situation suggests two possible

  6. Late Cretaceous and Eocene volcanism in the southern Line Islands and implications for hotspot theory

    NASA Astrophysics Data System (ADS)

    Haggerty, Janet A.; Schlanger, Seymour O.; Premoli Silva, Isabella

    1982-08-01

    Rocks dredged from a seamount 100 km northwest of Caroline Island, at the southern end of the Line Islands chain, contain Late Cretaceous fossils associated with volcanic debris. This association is evidence for the existence of a reef-bearing volcanic edifice with a minimum age of Late Cretaceous, 70 to 75 m.y., near Caroline Island. With the discovery of this seamount, the known occurrences of Late Cretaceous, reef-capped, volcanic edifices now extend a distance of 2,500 km, from Deep Sea Drilling Project Site 165 to 100 km northwest of Caroline Island. The apparent synchroneity of Late Cretaceous volcanism over this distance argues against the proposition that a single hotspot of the Hawaiian-Emperor type produced the Line Islands chain. Biochronologic data from the Line Islands indicate that the chain is not the temporal equivalent of the Emperor chain. Volcanic edifices of Cretaceous age are now known to extend from the Line Islands through the Mid-Pacific Mountains to the Marshall Islands and the western margin of the Pacific plate from Japan to the Marianas. A volcanic event occurred in the southern Line Islands during middle Eocene time; Eocene sediments were engulfed and altered by a volcanic eruption. The occurrence of both Cretaceous and Eocene volcanism in the southern Line Islands indicates that the history of the Line Islands is similar to that of the Marshall Islands. *Present addresses: (Haggerty) Department of Geosciences, University of Tulsa, Tulsa, Oklahoma 74104; (Schlanger) Department of Geological Sciences, Northwestern University, Evanston, Illinois 60201

  7. Wandering terranes in southern Alaska: The Aleutia Microplate and implications for the Bering Sea

    NASA Astrophysics Data System (ADS)

    Marlow, Michael S.; Cooper, Alan K.

    1983-04-01

    Paleomagnetic and geological data suggest that much of southern Alaska is a collage of tectonostratigraphic terranes which originated in Mesozoic time at paleolatitudes far south of their present position. The time of `docking' of the terranes against cratonic Alaska is critical to defining their amalgamated size and extent during their northward motion as well as their role in the evolution of the Bering Sea. One of the largest of the tectonostratigraphic terranes, the Peninsular terrane of south central and southwestern Alaska, extends offshore along the outer Bering Sea continental margin (Beringia). Paleomagnetic data suggest that this terrane has moved northward through all of Cenozoic time, but geologic data imply that the terrane had accreted to Alaska by the end of the Mesozoic. In early Cenozoic time the eastern part of the Aleutian arc appears to have been superimposed on the Peninsular terrane, and postulated northward Cenozoic motion of the terrane would therefore have required northward motion of the arc. Two accretion models, based on docking times for terranes in Alaska, are proposed, and they illustrate that large areas of the abyssal Bering Sea, the Alaska Peninsula, the Aleutian arc, and the Beringian continental margin may be part of a superterrane or microplate called Aleutia (microplate as defined by Beck et al. (1980), i.e., a microplate is a displaced segment of lithosphere that has crustal roots, whereas a superterrane is an amalgamation of terranes which may or may not be rootless). Model A implies that the Aleutian arc developed in situ on the southern edge of Aleutia after the microplate had docked. In model B, the final docking time of the Peninsular terrane is late Cenozoic, which implies that the Aleutia microplate encompasses a mammoth area that includes parts of southern Alaska, the Alaska Peninsula, the southern Beringian margin, the abyssal Bering Sea (Kula plate), and the Aleutian arc. If model A is correct, the docking time of

  8. Structural development of the southern basin, onshore Trinidad: Implications for hydrocarbon entrapment

    SciTech Connect

    Aden, L.J.; Bierley, R.E.

    1996-08-01

    Episodic compressional deformation across onshore southern Trinidad formed a complex spectrum of fold timing and fold types. Successful oil traps are not related to a specific time interval of structural formation, a specific oil expulsion event or a specific fold morphology. Traps that retained hydrocarbons may be related to seal facies. The tectono-stratigraphic section of onshore southern Trinidad, south of the Central Ranges, is comprised of three generalized depositional packages. Firstly, a southerly sourced Cretaceous to late Oligocene passive margin sequence of deepwater sands, shales and marls; secondly, a northerly sourced late Oligocene through middle Miocene syntectonic sequence of shallow to deep-water sands and shales; and thirdly, a west-southwesterly sourced late Miocene through Pleistocene shelfal sequence. Observations of compressional structures that folded these sediments during an early period of compressional deformation 25-10 million years before present suggest that all mudrock lithofacies could act as effective seals and trap hydrocarbons. Subsequent structural modification that occurred during a late period of compressional deformation between 5 million years and present day caused refolding and refaulting of these traps. Restructured traps that were sealed by brittle, Mesozoic deep-water facies failed and hydrocarbons migrated to shallower structural levels. Restructured folds that were sealed by ductile, Tertiary shallow-water facies retained trap fill.

  9. Salp/krill interactions in the Southern Ocean: spatial segregation and implications for the carbon flux

    NASA Astrophysics Data System (ADS)

    Pakhomov, E. A.; Froneman, P. W.; Perissinotto, R.

    Available data on the spatial distribution and feeding ecophysiology of Antarctic krill, Euphausia superba, and the tunicate, Salpa thompsoni, in the Southern Ocean are summarized in this study. Antarctic krill and salps generally display pronounced spatial segregation at all spatial scales. This appears to be the result of a clear biotopical separation of these key species in the Antarctic pelagic food web. Krill and salps are found in different water masses or water mass modifications, which are separated by primary or secondary frontal features. On the small-scale (<100 km), Antarctic krill and salps are usually restricted to the specific water parcels, or are well segregated vertically. Krill and salp grazing rates estimated using the in situ gut fluorescence technique are among the highest recorded in the Antarctic pelagic food web. Although krill and salps at times may remove the entire daily primary production, generally their grazing impact is moderate (⩽50% of primary production). The regional ecological consequences of years of high salp densities may be dramatic. If the warming trend, which is observed around the Antarctic Peninsula and in the Southern Ocean, continues, salps may become a more prominent player in the trophic structure of the Antarctic marine ecosystem. This likely would be coupled with a dramatic decrease in krill productivity, because of a parallel decrease in the spatial extension of the krill biotope. The high Antarctic regions, particularly the Marginal Ice Zone, have, however, effective physiological mechanisms that may provide protection against the salp invasion.

  10. Humpback Whale Song on the Southern Ocean Feeding Grounds: Implications for Cultural Transmission

    PubMed Central

    Garland, Ellen C.; Gedamke, Jason; Rekdahl, Melinda L.; Noad, Michael J.; Garrigue, Claire; Gales, Nick

    2013-01-01

    Male humpback whales produce a long, complex, and stereotyped song on low-latitude breeding grounds; they also sing while migrating to and from these locations, and occasionally in high-latitude summer feeding areas. All males in a population sing the current version of the constantly evolving display and, within an ocean basin, populations sing similar songs; however, this sharing can be complex. In the western and central South Pacific region there is repeated cultural transmission of song types from eastern Australia to other populations eastward. Song sharing is hypothesized to occur through several possible mechanisms. Here, we present the first example of feeding ground song from the Southern Ocean Antarctic Area V and compare it to song from the two closest breeding populations. The early 2010 song contained at least four distinct themes; these matched four themes from the eastern Australian 2009 song, and the same four themes from the New Caledonian 2010 song recorded later in the year. This provides evidence for at least one of the hypothesized mechanisms of song transmission between these two populations, singing while on shared summer feeding grounds. In addition, the feeding grounds may provide a point of acoustic contact to allow the rapid horizontal cultural transmission of song within the western and central South Pacific region and the wider Southern Ocean. PMID:24278134

  11. Spatial genetic structure and regional demography in the southern torrent salamander: Implications for conservation and management

    USGS Publications Warehouse

    Miller, Mark P.; Haig, Susan M.; Wagner, R.S.

    2006-01-01

    The Southern torrent salamander (Rhyacotriton variegatus) was recently found not warranted for listing under the US Endangered Species Act due to lack of information regarding population fragmentation and gene flow. Found in small-order streams associated with late-successional coniferous forests of the US Pacific Northwest, threats to their persistence include disturbance related to timber harvest activities. We conducted a study of genetic diversity throughout this species' range to 1) identify major phylogenetic lineages and phylogeographic barriers and 2) elucidate regional patterns of population genetic and spatial phylogeographic structure. Cytochrome b sequence variation was examined for 189 individuals from 72 localities. We identified 3 major lineages corresponding to nonoverlapping geographic regions: a northern California clade, a central Oregon clade, and a northern Oregon clade. The Yaquina River may be a phylogeographic barrier between the northern Oregon and central Oregon clades, whereas the Smith River in northern California appears to correspond to the discontinuity between the central Oregon and northern California clades. Spatial analyses of genetic variation within regions encompassing major clades indicated that the extent of genetic structure is comparable among regions. We discuss our results in the context of conservation efforts for Southern torrent salamanders.

  12. Phylogeography and spatial genetic structure of the Southern torrent salamander: Implications for conservation and management

    USGS Publications Warehouse

    Miller, M.P.; Haig, S.M.; Wagner, R.S.

    2006-01-01

    The Southern torrent salamander (Rhyacotriton variegatus) was recently found not warranted for listing under the US Endangered Species Act due to lack of information regarding population fragmentation and gene flow. Found in small-order streams associated with late-successional coniferous forests of the US Pacific Northwest, threats to their persistence include disturbance related to timber harvest activities. We conducted a study of genetic diversity throughout this species' range to 1) identify major phylogenetic lineages and phylogeographic barriers and 2) elucidate regional patterns of population genetic and spatial phylogeographic structure. Cytochrome b sequence variation was examined for 189 individuals from 72 localities. We identified 3 major lineages corresponding to nonoverlapping geographic regions: a northern California clade, a central Oregon clade, and a northern Oregon clade. The Yaquina River may be a phylogeographic barrier between the northern Oregon and central Oregon clades, whereas the Smith River in northern California appears to correspond to the discontinuity between the central Oregon and northern California clades. Spatial analyses of genetic variation within regions encompassing major clades indicated that the extent of genetic structure is comparable among regions. We discuss our results in the context of conservation efforts for Southern torrent salamanders. ?? The American Genetic Association. 2006. All rights reserved.

  13. Seismicity and crustal structure studies of southern California: tectonic implications from improved earthquake locations

    SciTech Connect

    Corbett, E.J.

    1984-01-01

    The 5.1 M/sub L/ Santa Barbara earthquake of 13 August 1978 was located 3 km southeast of Santa Barbara at a focal depth of 12.7 km. The temporal-spatial development of the aftershock zone may indicate that the initial rupture plane was considerably smaller than that of the eventual aftershock zone. The aftershock hypocenters outline a nearly horizontal plane (dipping 15/sup 0/ or less) at 13-km depth and the preferred focal mechanism indicates north-over-south thrusting. To further test the decollement hypothesis, Caltech catalog locations were reviewed to determine the depth distribution of earthquakes in the Transverse Ranges. The seismogenic zone is thickest along the southern front of the Transverse Ranges and is thinnest in the southern Mojave Desert and at the east end of the Transverse Ranges. The seismicity of the western Transverse Ranges is typified by north-dipping planar structures and the eastern Transverse Ranges are typified by pervasive seismicity extending down to the floor of the seismogenic zone. Data from a large quarry explosion on Catalina Island were utilized to derive a 3-layer Continental Borderland velocity structure to improve the locations of the 1981 Santa Barbara Island earthquakes. The Santa Barbara Island earthquake (5.3 M/sub L/) occurred on September 4, 1981. Aftershocks exhibited a clear northwest-southeast alignment that coincides with the submarine escarpment of the Santa Cruz-Catalina fault and was consistent with focal mechanisms.

  14. Epidemiological Trends for HIV in Southern Africa: Implications for Reaching the Elimination Targets.

    PubMed

    Williams, Brian G; Gouws, Eleanor; Somse, Pierre; Mmelesi, Mpho; Lwamba, Chibwe; Chikoko, Trouble; Fazito, Erika; Turay, Mohamed; Kiwango, Eva; Chikukwa, Pepukai; Damisoni, Henry; Gboun, Michael

    2015-06-01

    Southern Africa is the region worst affected by HIV in the world and accounts for one third of the global burden of HIV. Achieving the UNAIDS 90-90-90 target by 2020 and ending the AIDS epidemic by 2030 depend on success in this region. We review epidemiological trends in each country in southern Africa with respect to the prevalence, incidence, mortality, coverage of anti-retroviral therapy (ART) and TB notification rates, to better understand progress in controlling HIV and TB and to determine what needs to be done to reach the UNAIDS targets. Significant progress has been made in controlling HIV. In all countries in the region, the prevalence of HIV in people not on ART, the incidence of HIV, AIDS-related mortality and, in most countries, TB notification rates, are falling. In some countries, the risk of infection began to fall before biomedical interventions such as ART became widely available as a result of effective prevention measures or people's awareness of, and response to, the epidemic but the reasons for these declines remain uncertain. Some countries have achieved better levels of ART coverage than others, but all are in a position to reach the 2020 and 2030 targets if they accelerate the roll-out of ART and of targeted prevention efforts. Achieving the HIV treatment targets will further reduce the incidence of HIV-related TB, but efforts to control TB in HIV-negative people must be improved and strengthened. PMID:25929961

  15. Surveying the context for the implementation of UPE in the Sudan

    NASA Astrophysics Data System (ADS)

    Hajjar, Habib

    1983-06-01

    In 1977 the Government of the Sudan adopted a Plan with the long-term aim of universalizing primary education by the end of 1990. In spite of real accomplishments in education since the launching of the UPE scheme, there is a widespread conviction that the attainment of this objective will be delayed far beyond 1990 unless serious measures are taken to modify existing trends and imbalances. The following article, based on available information from the Sudan and on a microplanning study undertaken jointly by IIEP and the Sudanese Ministry of Education in 1981, is an attempt to draw some lessons from the Sudanese experience of UPE, highlighting the major difficulties encountered in implementing this policy and raising some of the implications of such a scheme for planning methods and perspectives. Although a host of financial and material problems (lack of resources, problems of communication, etc.) may be pointed out, one must not forget the pressure of existing trends and imbalances such as the `upward thrust' in the development of the Sudanese school system, which contrasts with the top priority accorded in theory to primary education. The existing planning methods laid down by the central level and formed within a uniform and general setting, scarcely suit the variety of local situations in a country like the Sudan where the different regions are very diverse in their geographic, economic, ethnic and political composition.

  16. Education in the Sudan: The Privileging of an Islamic Discourse

    ERIC Educational Resources Information Center

    Breidlid, Anders

    2005-01-01

    This article examines the educational discourse in the part of the Sudan administered by the Government of the Sudan. It first analyses the value system upon which the Sudanese education is based by focusing on the nature of Islamism. Such a discussion is necessary because the dominant discourse is a discourse where power and Islamic theocracy…

  17. The Dinka of Sudan: Family Traditions in Transition.

    ERIC Educational Resources Information Center

    Singleton, Kate

    This paper examines the core values of the Dinka tribe of Sudan, focusing on the most prominent aspects of their family life. The paper also examines how the Dinka family is changing in the face of Sudan's civil war and modernization. It concludes with suggestions for new directions that social work can take to facilitate the transition of the…

  18. 31 CFR 538.415 - Payments involving Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Payments involving Sudan. 538.415 Section 538.415 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... § 538.415 Payments involving Sudan. Before a United States financial institution initiates a...

  19. 31 CFR 538.415 - Payments involving Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Payments involving Sudan. 538.415 Section 538.415 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... § 538.415 Payments involving Sudan. Before a United States financial institution initiates a...

  20. 31 CFR 538.415 - Payments involving Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Payments involving Sudan. 538.415 Section 538.415 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... § 538.415 Payments involving Sudan. Before a United States financial institution initiates a...

  1. 31 CFR 538.415 - Payments involving Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Payments involving Sudan. 538.415 Section 538.415 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... § 538.415 Payments involving Sudan. Before a United States financial institution initiates a...

  2. 31 CFR 538.415 - Payments involving Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Payments involving Sudan. 538.415 Section 538.415 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE... § 538.415 Payments involving Sudan. Before a United States financial institution initiates a...

  3. 15 CFR 742.10 - Anti-terrorism: Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...-CCL BASED CONTROLS § 742.10 Anti-terrorism: Sudan. (a) License requirements. (1) If AT column 1 or AT column 2 1 of the Country Chart (Supplement No. 1 to part 738 of the EAR) is indicated in the appropriate ECCN, a license is required for export to Sudan for anti-terrorism purposes. 1 AT column 1 refers...

  4. 75 FR 62069 - Federal Acquisition Regulation; Sudan Waiver Process

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ... Federal Acquisition Regulation; Sudan Waiver Process AGENCIES: Department of Defense (DoD), General... criteria that an agency must address in a waiver request and a waiver consultation process regarding... Operations in Sudan and Imports from Burma, in the Federal Register at 74 FR 40463 on August 11,...

  5. 76 FR 68037 - Federal Acquisition Regulation; Sudan Waiver Process

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ... Regulation; Sudan Waiver Process AGENCIES: Department of Defense (DoD), General Services Administration (GSA... that conducts restricted business operations in Sudan. The rule also describes the consultation process... Federal Register at 75 FR 62069 on October 7, 2010, to revise FAR 25.702, Prohibition on contracting...

  6. Tectonic implications of a paleomagnetic study of the Sarmiento Ophiolitic Complex, southern Chile

    NASA Astrophysics Data System (ADS)

    Rapalini, A. E.; Calderón, M.; Singer, S.; Hervé, F.; Cordani, U.

    2008-06-01

    A paleomagnetic study was carried out on the Late Jurassic Sarmiento Ophiolitic Complex (SOC) exposed in the Magallanes fold and thrust belt in the southern Patagonian Andes (southern Chile). This complex, mainly consisting of a thick succession of pillow-lavas, sheeted dikes and gabbros, is a seafloor remnant of the Late Jurassic to Early Cretaceous Rocas Verdes basin that developed along the south-western margin of South America. Stepwise thermal and alternating field demagnetization permitted the isolation of a post-folding characteristic remanence, apparently carried by fine grain (SD?) magnetite, both in the pillow-lavas and dikes. The mean "in situ" direction for the SOC is Dec: 286.9°, Inc: - 58.5°, α95: 6.9°, N: 11 (sites). Rock magnetic properties, petrography and whole-rock K-Ar ages in the same rocks are interpreted as evidence of correlation between remanence acquisition and a greenschist facies metamorphic overprint that must have occurred during latest stages or after closure and tectonic inversion of the basin in the Late Cretaceous. The mean remanence direction is anomalous relative to the expected Late Cretaceous direction from stable South America. Particularly, a declination anomaly over 50° is suggestively similar to paleomagnetically interpreted counter clockwise rotations found in thrust slices of the Jurassic El Quemado Fm. located over 100 km north of the study area in Argentina. Nevertheless, a significant ccw rotation of the whole SOC is difficult to reconcile with geologic evidence and paleogeographic models that suggest a narrow back-arc basin sub-parallel to the continental margin. A rigid-body 30° westward tilting of the SOC block around a horizontal axis trending NNW, is considered a much simpler explanation, being consistent with geologic evidence. This may have occurred as a consequence of inverse reactivation of old normal faults, which limit both the SOC exposures and the Cordillera Sarmiento to the East. The age of tilting

  7. Footprints of large theropod dinosaurs and implications on the age of Triassic biotas from Southern Brazil

    NASA Astrophysics Data System (ADS)

    da Silva, Rafael Costa; Barboni, Ronaldo; Dutra, Tânia; Godoy, Michel Marques; Binotto, Raquel Barros

    2012-11-01

    Dinosaur footprints found in an outcrop of the Caturrita Formation (Rio Grande do Sul State, Southern Brazil), associated with a diverse and well preserved record of fauna and flora, reopen the debate about its exclusive Triassic age. The studied footprints were identified as Eubrontes isp. and are interpreted as having been produced by large theropod dinosaurs. The morphological characteristics and dimensions of the footprints are more derived than those commonly found in the Carnian-Norian, and are more consistent with those found during the Rhaetian-Jurassic. The trackmaker does not correspond to any type of dinosaur yet known from Triassic rocks of Brazil. Recent studies with the paleofloristic content of this unit also support a more advanced Rhaetian or even Jurassic age for this unit.

  8. Mantle Flow Implications across Easter and Southern Africa from Shear Wave Splitting Measurements

    NASA Astrophysics Data System (ADS)

    Ramirez, C.; Nyblade, A.; Bagley, B. C.; Mulibo, G. D.; Tugume, F.; Wysession, M. E.; Wiens, D.; van der Meijde, M.

    2015-12-01

    In this study, we present new shear wave splitting results from broadband seismic stations in Botswana and Namibia, and combine them with previous results from stations in Kenya, Uganda, Tanzania, Malawi, Zambia, South Africa, Mozambique, Zimbabwe, and Angola to further examine the pattern of seismic anisotropy across southern Africa. The new results come from stations in northern Namibia and Botswana, which help to fill in large gaps in data coverage. Our preliminary results show that fast polarization directions overall trend in a NE orientation. The most noticeable measurements that deviate from this pattern are located around the Archean Tanzania Craton in eastern Africa. The general NE pattern of fast polarization directions is attributed to mantle flow linked to the African superplume. Smaller scale variations from this general direction can be explained by shape anisotropy in the lithosphere in magmatic regions in the East African rift system and to fossil anisotropy in the Precambrian lithosphere.

  9. Intradomiciliary behavior of Anopheles albimanus on the coastal plain of southern Mexico: implications for malaria control.

    PubMed

    Bown, D N; Rodriguez, M H; Arredondo-Jimenez, J I; Loyola, E G; Rodriguez, M C

    1993-09-01

    The postfeeding indoor resting behavior of Anopheles albimanus in experimental houses in southern México was investigated by using a mark-recapture procedure. The majority of mosquitoes rested inside houses after taking a blood meal indoors. There was a higher landing frequency on interior surfaces other than walls and roofs; however, mosquitoes rested for longer periods on these 2 surfaces. Successive landings on walls after short flights showed that mosquitoes gradually increased their mean landing height from 1.0 to 1.4 m. Similarly, mosquitoes resting at the base of inner roofs had a successive landing height range of about 0.5 m. Based on these observations and the potential for reduction of nearly 50% in the quantity of insecticide used and the time needed to apply it, village-scale studies involving the selective spraying of a 1-m-wide swath of insecticide on walls and on roofs are recommended in this area. PMID:8245943

  10. Three-dimensional P and S wave velocity structures of southern Peru and their tectonic implications

    NASA Technical Reports Server (NTRS)

    Cunningham, Paul S.; Roecker, Steven W.; Hatzfeld, Denis

    1986-01-01

    Arrival times of compressional and shear (S) waves from microearthquakes recorded in 1981 by an 18-station regional array are used to study the three-dimensional velocity structure of the crust and upper mantle of the central Andes. The data suggest a crustal thickness of about 40 km beneath the coast, increasing to about 70 km beneath the Cordillera Occidental. The inverse correlation between the dip in the Moho and the dip of the slab may indicate a broad-scale causal relation between the two. S wave velocities in the mantle between 70 and 130 km depth above the 30-degree dipping slab are low, possibly indicating the presence of a partially melted asthenosphere that may be responsible for the magmatic activity recorded in southern Peru.

  11. Paleozoic archipelagic tectonic evolution of Western Junggar, NW China: implications for continental growth of southern Altaids

    NASA Astrophysics Data System (ADS)

    Zhang, Jien; Xiao, Wenjiao; Han, Chunming; Ma, Chong; Song, Dongfang

    2013-04-01

    The Western Junggar, NW China, a dominant site for continental growth in Southern Altaids, bridges the Circum-Balkhash and Junggar belts and exposes ophiolite, igneous rocks and strata from Cambrian to Carboniferous. Recent updated data on structure, geochronology, geochemisty and paleomagnetism, integrated with previous data, present a newly Paleozoic spatial and temporal framework of Western Junggar. In Cambrian, the Western Junggar begins to birth at the Tangbale area to south, where occurs Ordovician blueschist and top-to-south vergence structures, indicating north-dipping subduction. This event triggers intra-arc extension to generate Ordovician island arc in the Hongguleleng-Xiemisitai area to north and seamount in the Mayile area, middle of Western Junggar. Until Silurian, a southeastward subduction begins in the extended back-arc basin to west of Mayile, occurring blueschist at the Barleik trench and the Nalunsuo magmatic arc, at the rear of which generates Devonian back-arc basin around the Durbut area. Meanwhile, a Silurian Xiemisitai magmatic arc has been developed at the northern part of Western Junggar, along which a northward subduction has emplaced the Tarbahatai ophiolite and generates the Carboniferous Sawur magmatic arc. At the middle part of Western Junggar, the coeval adakite and sanukitic dykes, charnockite, multiple properties of ophiolite and plutons, SSZ-like andesite, dacite and rhyolite and regional structures suggest that there develop double-subduction systems with ridge-trench interaction in Carboniferous. These features suggest that the Western Junggar experiences rollback, intra-oceanic extension and subduction polarity reversal/flip in back-arc basin settings. Furthermore, positive ɛNd(t) values and no huge movements of blocks suggest that the Western Junggar is amalgamated by juvenile elements with different orientations. Therefore, we conclude that the Western Junggar enlarges from an island arc to Paleozoic tectonic regime with

  12. Topographyc metrics in the southern sector of the Marche foothills: implication for active tectonic analysis

    NASA Astrophysics Data System (ADS)

    Materazzi, Marco; Aringoli, Domenico; Carducci, Tamara; Cavitolo, Paolo; Farabollini, Piero; Giacopetti, Marco; Pambianchi, Gilberto; Tondi, Emanuele; Troiani, Francesco

    2016-04-01

    Quantitative geomorphic analysis can be provided a useful contribution to the study of recent tectonics. Some parameters, that quantify the channels morphology, as the Stream Length-Gradient (SL) Index (Hack, 1973) and the Steepness (Ks) Index (Flint, 1974), are generally used to detect anomalies on the expected concave-up equilibrium stream-profile, which can result in local abrupt changes in stream gradient (i.e., knickpoints) and/or broad convexities on stream long-profiles extending for tens of kilometres (i.e., knickzones). The main goal of this work is the study of the morphological and morphometrical features in the southern sector of the Marche Region, with the aim to gain new knowledge on the influences of rock resistance and rock uplift on the fluvial and topographic system. The investigated area is situated in central Italy and it extends from the axial zone of the Umbria-Marche Apennines to the Adriatic Sea, including the southern sector of the Marche Region and belongs to the foredeep domain of the Apennines orogenic system, which has affected by tectonic activity up to very recent times. The rheology of outcropping deposits doesn't allow the strain to be easily recorded at the outcrop scale. The analyses have been aimed at to test the sensitivity of both SL and Ks for evaluating active crustal deformations, acting at different wavelengths on land surface, within a low tectonically active thrust-and-fold belt. Additional purpose was the understanding of the pattern of regional differential crustal activity in the topographic arrangement of the study area In this research project two sets of analysis were conducted. References Hack J.T. 1973. Stream-profile analysis and stream-gradient index. Journal of Research of the U.S. Geological Survey, 1, 421-429. Flint J.J. 1974. Stream gradient as a function of order, magnitude and discharge. Water Resources Research, 10, 969-973.

  13. Recent Rifting Events in the Southern Red Sea and Regional Implications

    NASA Astrophysics Data System (ADS)

    Ruch, J.; Xu, W.; Jonsson, S.

    2014-12-01

    During the last decades, several rifting events on land have been observed along divergent plate boundaries, separating plates up to several meters in a few weeks. These events are typically accompanied by short-term seismic swarms (<15 days) and normal faulting, and are in some cases followed by eruptions as well. These on land rifting events represent, however, a very limited portion (< 2%) of global intrusions that take place in most cases along mid-ocean ridge systems. Here we focus on the southern Red Sea area, which is a part of the triple junction separating the Nubian, Somalian and Arabian plates where several earthquake swarms were recorded from 2000 to 2014. In three cases, these swarms were followed by eruptions within a year, at Jebel at Tair (2007) and in the Zubair Archipelago (40 km south) were two new volcanic islands developed in 2011 and 2013. Without the surface eruptions, these intrusive events may have remained unnoticed. Together the surface evidence of volcanic activity and recorded seismic swarms during the past two decades allow for a better definition of the overall magmatic activity in the southern Red Sea. We further discuss the possibility that Zubair, which is an emerged portion of a shallow 20 km-long by 5 km-wide NNW-SSE oriented platform, may be the surface expression of an active spreading center, comparable in size with other on land spreading centers. The recent concentration of activity at Zubair developed in a context of high regional magmatic and tectonic activity, including the rifting episode at Dabbahu (2005-2011), the rifting event in the Gulf of Aden (2010-2011) and the 2011 Nabro volcano eruption. Preliminary analysis of regional structural features and volcano lineaments suggest distinct intrusion paths and faulting running parallel to the three main active rift zone axes, and also along a dominant NE-SW oriented preexisting regional fault zones affecting the entire triple junction area.

  14. Implications of magmatic records for Neotethyan subduction beneath the Eurasian margin (Lhasa terrane, southern Tibet)

    NASA Astrophysics Data System (ADS)

    Tan, Jieqing; Aitchison, Jonathan

    2014-05-01

    Evidence for magmatism is widely developed in the Lhasa terrane of southern Tibet. Much of this is related to northward subduction of the Neotethyan Ocean prior the India-Eurasia collision. To better understand the tectono-magmatism, we systematically studied the published data for Middle Jurassic-Eocene igneous rocks in southern Tibet. Many of these rocks formed during two important intervals from ca. 110-80 Ma and ca. 65-40 Ma. On the basis of the reported rocks in this area, we considered the possibility that a Neotethyan mid-ocean ridge was subducted during the early peak episode (ca. 110-80 Ma). With this ridge subduction system, hot asthenosphere rose up through a slab window causing both oceanic slab and mantle wedge melting that resulted in peak volcanism during the Late Cretaceous. As young and hot crust at a mid-ocean ridge has a relatively low density, and thus potentially positive buoyancy, the subduction of a buoyant mid-ocean ridge may have led to a reduction in the angle of subduction. Evidence for termination of arc magmatism by the flat subducted oceanic slab is recorded by a magmatic gap ca. 80-65 Ma. Around ca. 65 Ma, the magmatic record appears again accompanied by a southward migration that represents resumption of an oceanic slab subduction at a normal subduction angle. Subsequently, magmatism lasts to ca. 36 Ma before the India-Eurasia collision and reached a peak of activity associated with a magmatic flare-up at 50 Ma. In this subduction system, some magmatic processes triggered formation of porphyry ore deposits and affected the temporal and spatial distribution of ores.

  15. The Variscan belt of Northern France Southern Belgium: geodynamic implications of new palaeomagnetic data

    NASA Astrophysics Data System (ADS)

    Márton, Emő; Mansy, Jean-Louis; Averbuch, Olivier; Csontos, László

    2000-09-01

    Palaeomagnetic investigations were carried out in Devonian-early Carboniferous rocks of the Variscan foreland chain of Northern France-Southern Belgium in order to reveal the origin of its arcuate shape. The Brabant Parautochthon was sampled in the Boulonnais (near Calais) and near Tournai, while the Ardenne Allochthon was sampled near Maubeuge and in the Givet area. All the sampled localities yielded characteristic remanent magnetization as a result of stepwise demagnetization and component analysis. Fold or tilt tests were possible for three localities, with negative results indicating pervasive remagnetization. The tectonic position was sub-horizontal at two localities, while the tilt was monoclinal for the rest. Therefore, the acquisition time of the magnetic signals was estimated by comparing the palaeolatitude computed from each magnetic component to the palaeolatitudes of Variscan Europe calculated after Van der Voo (1993). Three components showing: A, a southern B, a near-Equatorial, and C, a northern palaeolatitude are recognized from our data. Since a pre-Variscan age of component A (observed only in Boulonnais, at 10 sites) is not supported by data, it is assigned to an early phase of deformation. Component B (16 sites) was acquired during the peak of the Variscan tectonics (late Westphalian), while component C (five sites) originated during Permian times. Regardless of the palaeolatitudes, declinations fall between 190 and 210°, thus being conformable with the declinations expected for Variscan Europe. The declinations show no correlation with the arcuate shape of the belt, neither are they different in the Paraauthochthon and in the Allochthon, nor in the different components. Arc formation by moulding of the Allochthon on the Brabant Parautochthon is, therefore, not supported by these data, since this mechanism requires substantial (opposed) rotations on both wings of the arc. The available palaeomagnetic data are conformable with a pre-formed arc

  16. 31 CFR 538.522 - Transactions related to U.S. citizens residing in Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... residing in Sudan. 538.522 Section 538.522 Money and Finance: Treasury Regulations Relating to Money and.... citizens residing in Sudan. U.S. persons are authorized to engage in transactions in Sudan ordinarily... reside on a permanent basis in Sudan....

  17. 31 CFR 538.522 - Transactions related to U.S. citizens residing in Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... residing in Sudan. 538.522 Section 538.522 Money and Finance: Treasury Regulations Relating to Money and.... citizens residing in Sudan. U.S. persons are authorized to engage in transactions in Sudan ordinarily... reside on a permanent basis in Sudan....

  18. 31 CFR 538.522 - Transactions related to U.S. citizens residing in Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... residing in Sudan. 538.522 Section 538.522 Money and Finance: Treasury Regulations Relating to Money and.... citizens residing in Sudan. U.S. persons are authorized to engage in transactions in Sudan ordinarily... reside on a permanent basis in Sudan....

  19. 31 CFR 538.522 - Transactions related to U.S. citizens residing in Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... residing in Sudan. 538.522 Section 538.522 Money and Finance: Treasury Regulations Relating to Money and.... citizens residing in Sudan. U.S. persons are authorized to engage in transactions in Sudan ordinarily... reside on a permanent basis in Sudan....

  20. 31 CFR 538.522 - Transactions related to U.S. citizens residing in Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... residing in Sudan. 538.522 Section 538.522 Money and Finance: Treasury Regulations Relating to Money and.... citizens residing in Sudan. U.S. persons are authorized to engage in transactions in Sudan ordinarily... reside on a permanent basis in Sudan....

  1. Reasons behind the Failure of Teaching Sudan Practical Integrated National English (SPINE 5) in Sudan

    ERIC Educational Resources Information Center

    Hamad, Mona M.

    2015-01-01

    According to the development of English language learning and curriculum design, English language series became a very important issue that affects education globally and in Sudan. In specific, this study reports reasons behind the failure of teaching SPINE 5 (which is one of SPINE series) from the teachers' point of view. In Bahry Locality in…

  2. The impact of war on women and children: case study of Sudan.

    PubMed

    El-nagar, S E

    1992-06-01

    Civil war has raged in southern Sudan from 1955 to 1972 and again from 1983 to the present. This situation has been compounded by regional conflicts in other parts of Sudan and wars in neighboring countries. The consequences of war are taking their toll on the entire region and are intensified by environmental hazards, desertification, drought, and famine. The socioeconomic and educational infrastructure has been destroyed in southern Sudan, taking the family support system with it. The atmosphere of continued fighting has made it all but impossible for relief agencies to provide services. The innocent victims of the war are civilians who are forced to choose between disastrous alternatives: if they flee, they lose their homes, their livelihoods, and their communities; if they stay, they watch these things being destroyed around them. Women and children are suffering the most. Hunger and disease are widespread, and immunization programs have been curtailed. Very few school-age children are receiving an education, and children are subject to kidnapping and abuse from soldiers. There may be as many as 3 million people displaced, with 1.5 million living in settled areas and 707,000 in camps in the Khartoum area. Relief aid in the camps is unreliable, and the displace women arrive with no assets or skills. They survive through domestic work, begging, petty trading, or beer-brewing and prostitution (the latter 2 are illegal). Children are left to fend for themselves all day or to find work in situations where they are exploited. In addition to depriving the children of their health, education, and economic stability, the war has resulted in cultural deprivation as ethnic groups lose their sense of identity. Psychological problems are the natural consequence of this situation, and aggressive behavior is seen in the displaced children, while trauma and anxiety plague the children in the war zones. PMID:12318292

  3. 31 CFR 538.505 - Provision of certain legal services to the Government of Sudan, persons in Sudan, or benefitting...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: (1) Provision of legal advice and counseling to the Government of Sudan, to a person in Sudan, or in... the laws of any jurisdiction within the United States, provided that such advice and counseling is not..., arbitration, or administrative proceedings; (3) Initiation of domestic U.S. legal, arbitration,...

  4. Mapping the Potential Risk of Mycetoma Infection in Sudan and South Sudan Using Ecological Niche Modeling

    PubMed Central

    Samy, Abdallah M.; van de Sande, Wendy W. J.; Fahal, Ahmed Hassan; Peterson, A. Townsend

    2014-01-01

    In 2013, the World Health Organization (WHO) recognized mycetoma as one of the neglected tropical conditions due to the efforts of the mycetoma consortium. This same consortium formulated knowledge gaps that require further research. One of these gaps was that very few data are available on the epidemiology and transmission cycle of the causative agents. Previous work suggested a soil-borne or Acacia thorn-prick-mediated origin of mycetoma infections, but no studies have investigated effects of soil type and Acacia geographic distribution on mycetoma case distributions. Here, we map risk of mycetoma infection across Sudan and South Sudan using ecological niche modeling (ENM). For this study, records of mycetoma cases were obtained from the scientific literature and GIDEON; Acacia records were obtained from the Global Biodiversity Information Facility. We developed ENMs based on digital GIS data layers summarizing soil characteristics, land-surface temperature, and greenness indices to provide a rich picture of environmental variation across Sudan and South Sudan. ENMs were calibrated in known endemic districts and transferred countrywide; model results suggested that risk is greatest in an east-west belt across central Sudan. Visualizing ENMs in environmental dimensions, mycetoma occurs under diverse environmental conditions. We compared niches of mycetoma and Acacia trees, and could not reject the null hypothesis of niche similarity. This study revealed contributions of different environmental factors to mycetoma infection risk, identified suitable environments and regions for transmission, signaled a potential mycetoma-Acacia association, and provided steps towards a robust risk map for the disease. PMID:25330098

  5. Implications of Stratigraphic and Structural Data from the Bitter Spring Region, Southern Nevada

    NASA Astrophysics Data System (ADS)

    Donatelle, A.; Goeden, J.; Hannon, M.; Hickson, T.; Holter, S.; Johnson, T.; Lamb, M.; Lindberg, J.

    2004-05-01

    Deposition of the Tertiary Horse Spring Formation (HSF) in southern Nevada has been used to infer varying styles of extensional and strike-slip basin formation. Beard (1996) proposes an initial large contiguous basin of Rainbow Gardens age (ca. 26-18 Ma) that is subsequently broken up into sub-basins during Thumb time (16-14 Ma). A key locality to test this hypothesis is near the southern end of East and West Longwell Ridges, on the Bitter Spring USGS 1:24000 quadrangle (BSQ). However, the stratigraphic framework in this area is poorly defined. The BSQ is located west of the Overton arm of Lake Mead near the junction of the Las Vegas Valley Shear Zone and the Lake Mead Fault System. By mapping a portion of the quadrangle at 1:5000 scale, measuring detailed sections, and collecting ash samples from key localities, we investigated the structural and sedimentary framework of the area and have begun to clarify the stratigraphic relationships between members of the HSF. Faults fall into three categories: one set strikes north and dips moderately to the west; another strikes east-northeast and dips shallowly to the northwest; and the last strikes north and dips to the east. Many of these faults show an oblique sense of movement and may be related to movement on the White Basin (WBF) and Rodgers Spring Faults (Bohannon, 1983). A distinctive resistant limestone caps gypsiferous and clastic units on both sides of the north-south trending WBF. To the west of the WBF, this limestone is mapped as the Bitter Ridge Limestone Member of the HSF, whereas to the east it is mapped as the Thumb Member by Beard (unpub) and as the Rainbow Gardens Member by Bohannon (1983). We suspect that these limestones may be correlative; geochemical and petrographic fingerprinting of numerous ashes from our sections should allow correlation of these units across the WBF. In addition, sections from the east side of the WBF spaced over 1.5 km show conglomerate at the base, overlain by a sequence of

  6. Ecological implications of Laurel Wilt infestation on Everglades Tree Islands, southern Florida

    USGS Publications Warehouse

    Snyder, James R.

    2014-01-01

    , laurel wilt disease also kills other native trees that are members of the laurel family, including swamp bay (Persea palustris), silk bay (Persea borbonia var. humilis), and sassafras (Sassafras albidum), as well as the economically important cultivated avocado (Persea americana) (Fraedrich and others, 2008). This paper is concerned primarily with swamp bay, an important component of Everglades tree islands.The spread of the redbay ambrosia beetle and its fungal symbiont has been very rapid, exceeding model predictions (Koch and Smith, 2008); by 2011, laurel wilt disease was found from the southern coastal plain of North Carolina to southern peninsular Florida. The first redbay ambrosia beetle was trapped in Miami-Dade County in March 2010, and laurel wilt disease was discovered in swamp bays in February 2011 and in commercial avocado groves about a year later (Kendra and others, 2013). By 2013, laurel wilt disease was seen in swamp bays throughout the southern Everglades in Everglades National Park, Big Cypress National Preserve, and Water Conservation Areas (WCAs) 3A and 3B (Rodgers and others, 2014).

  7. Modeling Fire Emissions across Central and Southern Italy: Implications for Land and Fire Management

    NASA Astrophysics Data System (ADS)

    Bacciu, V. M.; Salis, M.; Spano, D.

    2015-12-01

    Fires play a relevant role in the global and regional carbon cycle, representing a remarkable source of CO2 and other greenhouse gases (GHG) that influence atmosphere budgets and climate. In addition, the wildfire increase projected in Southern Europe due to climate change (CC) and concurrent exacerbation of extreme weather conditions could also lead to a significant rise in GHG. Recently, in the context of the Italian National Adaptation Strategy to Climate Change (SNAC), several approaches were identified as valuable tools to adapt and mitigate the impacts of CC on wildfires, in order to reduce landscape susceptibility and to contribute to the efforts of carbon emission mitigation proposed within the Kyoto protocol. Active forest and fuel management (such as prescribed burning, fuel reduction and removal, weed and flammable shrub control, creation of fuel discontinuity) is recognised to be a key element to adapt and mitigate the impacts of CC on wildfires. Despite this, overall there is a lack of studies about the effectiveness of fire emission mitigation strategies. The current work aims to analyse the potential of a combination of fuel management practices in mitigating emissions from forest fires and evaluate valuable and viable options across Central and Southern Italy. These objectives were achieved throughout a retrospective application of an integrated approach combining a fire emission model (FOFEM - First Order Fire Effect Model) with spatially explicit, comprehensive, and accurate fire, vegetation and weather data for the period 2004-2012. Furthermore, a number of silvicultural techniques were combined to develop several fuel management scenarios and then tested to evaluate their potential in mitigating fire emissions.The preliminary results showed the crucial role of appropriate fuel, fire behavior, and weather data to reduce bias in quantifying the source and the composition of fire emissions and to attain reasonable estimations. Also, the current

  8. The 2013 severe haze over the southern Hebei, China: model evaluation, source apportionment, and policy implications

    NASA Astrophysics Data System (ADS)

    Wang, L. T.; Wei, Z.; Yang, J.; Zhang, Y.; Zhang, F. F.; Su, J.; Meng, C. C.; Zhang, Q.

    2013-11-01

    Extremely severe and persistent haze occurred in January 2013 over the eastern and northern China. The record-breaking high concentrations of fine particulate matter (PM2.5) of more than 700 μg m-3 on hourly average and the persistence of the episodes have raised widespread, considerable public concerns. During that period, seven of the top ten polluted cities in China were within Hebei Province. The three cities in southern Hebei, Shijiazhuang, Xingtai, and Handan, have been listed as the top three polluted cities according to the statistics for the first half year of 2013. In this study, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are applied to simulate the 2013 severe winter regional hazes in East Asia and the northern China at horizontal grid resolutions of 36 and 12 km, respectively, using the Multi-resolution Emission Inventory of China (MEIC). The source contributions of major source regions and sectors to PM2.5 concentrations in the three most-polluted cities in southern Hebei are quantified aiming at the understanding of the sources of the severe haze pollution in this region, and the results are compared with December 2007, the haziest month in 2001-2010. Model evaluation against meteorological and air quality observations indicates an overall acceptable performance and the model tends to underpredict PM2.5 and coarse particulate matter (PM10) concentrations during the extremely severe polluted episodes. The MEIC inventory is proved to be a good estimation in terms of total emissions of cities but uncertainties exist in the spatial allocations of emissions into fine grid resolutions within cities. The source apportionment shows that emissions from the northern Hebei and the Beijing-Tianjin city cluster are two major regional contributors to the pollution in January 2013 in Shijiazhuang, comparing with those from Shanxi and the northern Hebei for December 2007. For Xingtai and

  9. The 2013 severe haze over southern Hebei, China: model evaluation, source apportionment, and policy implications

    NASA Astrophysics Data System (ADS)

    Wang, L. T.; Wei, Z.; Yang, J.; Zhang, Y.; Zhang, F. F.; Su, J.; Meng, C. C.; Zhang, Q.

    2014-03-01

    Extremely severe and persistent haze occurred in January 2013 over eastern and northern China. The record-breaking high concentrations of fine particulate matter (PM2.5) of more than 700 μg m-3 on hourly average and the persistence of the episodes have raised widespread, considerable public concerns. During that period, 7 of the top 10 polluted cities in China were within the Hebei Province. The three cities in southern Hebei (Shijiazhuang, Xingtai, and Handan) have been listed as the top three polluted cities according to the statistics for the first half of the year 2013. In this study, the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality (CMAQ) modeling system are applied to simulate the 2013 severe winter regional hazes in East Asia and northern China at horizontal grid resolutions of 36 and 12 km, respectively, using the Multi-resolution Emission Inventory for China (MEIC). The source contributions of major source regions and sectors to PM2.5 concentrations in the three most polluted cities in southern Hebei are quantified by aiming at the understanding of the sources of the severe haze pollution in this region, and the results are compared with December 2007, the haziest month in the period 2001-2010. Model evaluation against meteorological and air quality observations indicates an overall acceptable performance and the model tends to underpredict PM2.5 and coarse particulate matter (PM10) concentrations during the extremely polluted episodes. The MEIC inventory is proven to be a good estimation in terms of total emissions of cities but uncertainties exist in the spatial allocations of emissions into fine grid resolutions within cities. The source apportionment shows that emissions from northern Hebei and the Beijing-Tianjin city cluster are two major regional contributors to the pollution in January 2013 in Shijiazhuang, compared with those from Shanxi and northern Hebei for December 2007. For Xingtai and Handan

  10. Lagrangian tracing of Sahelian Sudan moisture sources

    NASA Astrophysics Data System (ADS)

    Salih, Abubakr A. M.; Zhang, Qiong; Tjernström, Michael

    2013-04-01

    Sahelian Sudan, 10° to 16°N, is an arid to semi-arid zone that separates the Saharan to the north and the wet Savannah to the south. The region is characterized by, relatively, limited water resources, and hence has a high dependency on the annual rainfall. According to the latest IPCC report, regions that have such limited water resources are highly vulnerable to the ongoing climate change and variability. Taking into account that the agriculture is the main economical activity, the variability in annual rainfall is of direct soci-economical relevance. Similar to the rest of the African Sahel, the rainy season, June through September, across Sahelian Sudan is connected to the annual march of the Intertropical Convergence Zone (ITCZ). However, there still a limited understanding of the actual sources of moisture that supplies this region with water vapor during the rainy season. Broadly speaking, the Atlantic, the Congo rain forest, the Read Sea and the Indian Ocean are the main potential sources. In this study we use Lagrangian tracing technique to indentify the sources of moisture of Sahelian Sudan and attempt quantifying their contribution to the total annual moisture convergence. For this we utilized output from the Lagrangian trajectory model FLEXPART driven by the meteorological fields from the European Center for Medium range Weather Forecast ERA-interim for period of ten years 2000 to 2009. We trace back, for ten days each mass element to indentify the source region. The models also accounts for precipitation and moisture uptakes through the course of the transport of the air parcel from source to destination. Identifying the sources of moisture is of great importance, and can help in two connected directions. First, identifying sources of moisture will help in understanding the variability and will provide insight about the drought causes and mechanisms. Second, revealing the moisture sources would enhance ongoing efforts in seasonal forecasting.

  11. Climate variability and El Niño Southern Oscillation: implications for natural coastal resources and management

    NASA Astrophysics Data System (ADS)

    Thatje, Sven; Heilmayer, Olaf; Laudien, Jürgen

    2008-03-01

    The El Niño Southern Oscillation (ENSO) significantly influences marine ecosystems and the sustained exploitation of marine resources in the coastal zone of the Humboldt Current upwelling system. Both its warm (El Niño: EN) and cold (La Niña: LN) phase have drastic implications for the ecology, socio-economy and infrastructure along most of Pacific South America. Local artisanal fisheries, which especially suffer from the effects of EN, represent a major part for the domestic economy of Chile and Peru and in consequence a huge amount of published and unpublished studies exists aiming at identifying effects of EN and LN. However, most processes and underlying mechanisms fostering the ecology of organisms along Pacific South America have not been analyzed yet and for the marine realm most knowledge is traditionally based on rather descriptive approaches. We herein advocate that small-scale comparative and interdisciplinary process studies work as one possible solution to understand better the variability observed in EN/LN effects at local scale. We propose that differences in small-scale impacts of ENSO along the coast rather than the macro-ecological and oceanographic view are essential for the sustainable management of costal ecosystems and the livelihood of the people depending on it. Based on this, we summarize the conceptual approach from the EU-funded International Science and Technology Cooperation (INCO) project “Climate variability and El Niño Southern Oscillation: Implications for Natural Coastal Resources and Management (CENSOR)” that aims at enhancing the detection, compilation, and understanding of EN and LN effects on the coastal zone and its natural resources. We promote a multidisciplinary avenue within present international funding schemes, with the intention to bridge the traditional gap between basic and applied coastal research. The long-term aim is an increased mitigation of harm caused by EN as well as a better use of beneficial effects

  12. Dental microwear of sympatric rodent species sampled across habitats in southern Africa: Implications for environmental influence.

    PubMed

    Burgman, Jenny H E; Leichliter, Jennifer; Avenant, Nico L; Ungar, Peter S

    2016-03-01

    Dental microwear textures have proven to be a valuable tool for reconstructing the diets of a wide assortment of fossil vertebrates. Nevertheless, some studies have recently questioned the efficacy of this approach, suggesting that aspects of habitat unrelated to food preference, especially environmental grit load, might have a confounding effect on microwear patterning that obscures the diet signal. Here we evaluate this hypothesis by examining microwear textures of 3 extant sympatric rodent species that vary in diet breadth and are found in a variety of habitat types: Mastomys coucha, Micaelamys namaquensis and Rhabdomys pumilio. We sample each of these species from 3 distinct environmental settings in southern Africa that differ in rainfall and vegetative cover: Nama-Karoo shrublands (semi-desert) and Dry Highveld grasslands in the Free State Province of South Africa, and Afromontane (wet) grasslands in the highlands of Lesotho. While differences between habitat types are evident for some of the species, inconsistency in the pattern suggests that the microwear signal is driven by variation in foods eaten rather than grit-level per se. It is clear that, at least for species and habitats sampled in the current study, environmental grit load does not swamp diet-related microwear signatures. PMID:26748948

  13. Environmental and Archaeological Implications of a Late Quaternary Palynological Sequence, Poyang Lake, Southern China

    NASA Astrophysics Data System (ADS)

    Jiang, Qinhua; Piperno, Dolores R.

    1999-09-01

    Paleoecological data from Poyang Lake, southern China, indicate that significant natural and human-induced vegetational changes have occurred during the Late Quaternary in the Middle Yangtze River valley, the likely location of rice (Oryza sativa L.) domestication. During the late Pleistocene (from ca. 12,830 to ca. 10,500 yr B.P.), the climate was cooler and drier than today's. The subtropical, mixed deciduous-evergreen broad-leaved forest which constitutes the modern, potential vegetation was reduced and herbaceous vegetative cover expanded. A hiatus in sedimentation occurred in Poyang Lake, beginning sometime after ca. 10,500 yr B.P. and lasting until the middle Holocene (ca. 4000 yr B.P.). At ca. 4000 yr B.P., the regional vegetation was a diverse, broad-leaved forest dominated by many of the same arboreal elements (e.g., Quercus, Castanopsis, Liquidambar) that grow in the area today. A significant reduction of arboreal pollen and an increase of herbaceous pollen at ca. 2000 yr B.P. probably reflect human influence on the vegetation and the expansion of intensive rice agriculture into the dryland forests near the river valleys.

  14. Clinical and Pharmacogenomic Implications of Genetic Variation in a Southern Ethiopian Population

    PubMed Central

    Tekola-Ayele, Fasil; Adeyemo, Adebowale; Aseffa, Abraham; Hailu, Elena; Finan, Chris; Davey, Gail

    2014-01-01

    Africa is home to genetically diverse human populations. We compared the genetic structure of the Wolaita ethnic population from southern Ethiopia (WETH, n=120) with HapMap populations using genome-wide variants. We investigated allele frequencies of 443 clinically and pharmacogenomically relevant genetic variants in WETH compared to HapMap populations. We found that WETH were genetically most similar to the Kenya Maasai and least similar to the Japanese in HapMap. Variant alleles associated with increased risk of adverse reactions to drugs used for treating tuberculosis (rs1799929 and rs1495741 in NAT2), thromboembolism (rs7294, rs9923231 and rs9934438 in VKORC1), and HIV/AIDS and solid tumors (rs2242046 in SLC28A1) had significantly higher frequencies in WETH compared to African ancestry HapMap populations. Our results illustrate that clinically relevant pharmacogenomic loci display allele frequency differences among African populations. We conclude that drug dosage guidelines for important global health diseases should be validated in genetically diverse African populations. PMID:25069476

  15. Folklore and traditional ecological knowledge of geckos in Southern Portugal: implications for conservation and science.

    PubMed

    Ceríaco, Luis M P; Marques, Mariana P; Madeira, Natália C; Vila-Viçosa, Carlos M; Mendes, Paula

    2011-01-01

    Traditional Ecological Knowledge (TEK) and folklore are repositories of large amounts of information about the natural world. Ideas, perceptions and empirical data held by human communities regarding local species are important sources which enable new scientific discoveries to be made, as well as offering the potential to solve a number of conservation problems. We documented the gecko-related folklore and TEK of the people of southern Portugal, with the particular aim of understanding the main ideas relating to gecko biology and ecology. Our results suggest that local knowledge of gecko ecology and biology is both accurate and relevant. As a result of information provided by local inhabitants, knowledge of the current geographic distribution of Hemidactylus turcicus was expanded, with its presence reported in nine new locations. It was also discovered that locals still have some misconceptions of geckos as poisonous and carriers of dermatological diseases. The presence of these ideas has led the population to a fear of and aversion to geckos, resulting in direct persecution being one of the major conservation problems facing these animals. It is essential, from both a scientific and conservationist perspective, to understand the knowledge and perceptions that people have towards the animals, since, only then, may hitherto unrecognized pertinent information and conservation problems be detected and resolved. PMID:21892925

  16. Shear-wave splitting beneath southern Korea and its tectonic implication

    NASA Astrophysics Data System (ADS)

    Kang, Tae-Seob; Shin, Jin Soo

    2009-06-01

    Seismic anisotropy beneath the southern Korean Peninsula (SKP) was investigated based on the ScS waves of deep-focused earthquakes recorded at 35 broadband stations. The most striking feature of the observed splitting patterns is the preference of the fast directions (NW-SE) that are nearly parallel to the direction of the absolute plate motion in the region. However, the splitting patterns over the region show significant variation in splitting parameters indicating a complex anisotropic structure. Variations of the splitting directions and dissimilarity in the source domains of basaltic volcanisms suggest that the asthenospheric mantle flow since at least the late Cenozoic cannot explain the seismic anisotropy beneath the region. Comparison to shear-wave splitting measurements from eastern China revealed that the NW-SE fast direction of splitting measurements in the SKP is close to that in the North China block (NCB) while the NE-SW fast direction might be related to that in the South China block (SCB). The shallow mantle lithosphere beneath the SKP retains the fossil anisotropy amalgamated prior to the late Paleozoic before the collision between the NCB and SCB, and the anisotropic structure was not completely realigned by the major orogenic events during the late Paleozoic to Mesozoic eras.

  17. Folklore and traditional ecological knowledge of geckos in Southern Portugal: implications for conservation and science

    PubMed Central

    2011-01-01

    Traditional Ecological Knowledge (TEK) and folklore are repositories of large amounts of information about the natural world. Ideas, perceptions and empirical data held by human communities regarding local species are important sources which enable new scientific discoveries to be made, as well as offering the potential to solve a number of conservation problems. We documented the gecko-related folklore and TEK of the people of southern Portugal, with the particular aim of understanding the main ideas relating to gecko biology and ecology. Our results suggest that local knowledge of gecko ecology and biology is both accurate and relevant. As a result of information provided by local inhabitants, knowledge of the current geographic distribution of Hemidactylus turcicus was expanded, with its presence reported in nine new locations. It was also discovered that locals still have some misconceptions of geckos as poisonous and carriers of dermatological diseases. The presence of these ideas has led the population to a fear of and aversion to geckos, resulting in direct persecution being one of the major conservation problems facing these animals. It is essential, from both a scientific and conservationist perspective, to understand the knowledge and perceptions that people have towards the animals, since, only then, may hitherto unrecognized pertinent information and conservation problems be detected and resolved. PMID:21892925

  18. Subsidence and thermal history of Southern Oklahoma aulacogen: implications for petroleum exploration

    SciTech Connect

    Feinstein, S.

    1981-12-01

    Reconstructed subsidence curves and the thermal history of the Southern Oklahoma aulacogen support the concept of thermally controlled isostatic subsidence for the formation of the basin and indicate the significance of this concept for petroleum exploration. Two mechanisms - initial elastic flexure, followed by detachment and differential subsidence of the aulacogen - are inferred from the subsidence curves. Two methods have been used for reconstruction of the thermal history. A tectonophysics model in combination with a history of basin evolution demonstrates that geothermal gradient and depth-of-burial were dynamic variables during the subsidence stage; maximum paleotemperatures were attained during Sylvan (Late Ordovician) time near the close of subsidence; and most of the Arbuckle Group had been subjected to the temperature conditions of oil formation (the oil liquid window) prior to the possible phase of fluid migration in Sylvan time. The second method, involving reconstruction of the geothermal history on the basis of geothermometry (palynomorph carbonization), suggests: (1) paleotemperatures exerted a significant effect on the level of organic metamorphism in the sedimentary rocks; (2) the geothermal gradient varied during the subsidence stage; (3) paleotemperatures were higher than those predicted by the theoretical model and support the hypothesis of formation of the basin by thermally controlled subsidence, and the application of this concept for petroleum exploration.

  19. Tephrochronology of a 72 ka-long marine record: implications for the southern Tyrrhenian explosive volcanism

    NASA Astrophysics Data System (ADS)

    Tamburrino, Stella; Insinga, Donatella; Pelosi, Nicola; Kissel, Catherine; Laj, Carlo; Capotondi, Lucilla; Sprovieri, Mario

    2015-04-01

    Several discrete tephra layers occur in a Marion Dufresne 13.9 m-long deep-sea core (MD01-2474G) from the southern Tyrrhenian Sea. Major, minor and trace element data (EMPA-WDS and LA-ICP-MS analyses) from fresh micro-pumices and glass shards allow to correlate them with the volcanic activity from Aeolian Islands (Lipari, Vulcano, Salina), Campanian Plain (Ischia), Pantelleria and Mt. Etna. The chronology of the succession is provided by a high-resolution age-model based on isotope stratigraphy and AMS radiocarbon dating, which places the succession in a time interval spanning the last 72 kyrs BP. According to a detailed proximal-distal and distal-distal correlation, a precise chronological framework is established and some main markers tephras of the central Mediterranean area (Y-1, Y-6, Y-7 and Y-8) are recognised. In additions, the succession is a precious archive to record multiple volcanic events occurred at Ischia volcano and the Aeolian Arc (Lipari and Vulcano). This latter, in particular, erupted several products which exhibits strong compositional variations otherwise non detectable from terrestrial counterparts. The results of the present study, hence, provide new data for a detailed analytical reference database of the Tyrrhenian Sea tephrochronology and may contribute to a better chronostratigraphic reconstruction of the Aeolian arc explosive events.

  20. River channel adjustments in Southern Italy over the past 150 years and implications for channel recovery

    NASA Astrophysics Data System (ADS)

    Scorpio, Vittoria; Aucelli, Pietro P. C.; Giano, Salvatore I.; Pisano, Luca; Robustelli, Gaetano; Rosskopf, Carmen M.; Schiattarella, Marcello

    2015-12-01

    Multi-temporal GIS analysis of topographic maps and aerial photographs along with topographic and geomorphological surveys are used to assess evolutionary trends and key control factors of channel adjustments for five major rivers in southern Italy (the Trigno, Biferno, Volturno, Sinni and Crati rivers) to support assessment of channel recovery and river restoration. Three distinct phases of channel adjustment are identified over the past 150 years primarily driven by human disturbances. Firstly, slight channel widening dominated from the last decades of the nineteenth century to the 1950s. Secondly, from the 1950s to the end of the 1990s, altered sediment fluxes induced by in-channel mining and channel works brought about moderate to very intense incision (up to 6-7 m) accompanied by strong channel narrowing (up to 96%) and changes in channel configuration from multi-threaded to single-threaded patterns. Thirdly, the period from around 2000 to 2015 has been characterized by channel stabilization and local widening. Evolutionary trajectories of the rivers studied are quite similar to those reconstructed for other Italian rivers, particularly regarding the second phase of channel adjustments and ongoing transitions towards channel recovery in some reaches. Analyses of river dynamics, recovery potential and connectivity with sediment sources of the study reaches, framed in their catchment context, can be used as part of a wider interdisciplinary approach that views effective river restoration alongside sustainable and risk-reduced river management.

  1. Snow-avalanche impact landforms in Breheimen, southern Norway: Origin, age, and paleoclimatic implications

    SciTech Connect

    Matthews, J.A.; McCarroll, D. )

    1994-05-01

    Twelve snow-avalanche ramparts in Jostedalen and Sprongdalen (Breheimen, southern Norway) are investigated to elucidate processes of formation, the history of avalanche activity, and their potential for paleoclimatic reconstruction. Variation in the form of these riverbank boulder ramparts reflects local patterns of avalanche impact. Differences in clast roundness between ramparts, avalanche tracks, and river beds indicate that, on average, 50 to 60% of the clasts in the ramparts originate from river bedload as opposed to avalanche source areas or tracks. Rampart clasts increase in roundness downstream over a distance of 12 km, and the contribution from the river bed varies from 26 to 80% depending on local factors. Conventional lichenometric dating suggests ages for the initiation of rampart formation of 250 to 2000 yr, but they probably have a much longer history. Lichen-size frequency distributions, using the largest lichen from each of n boulders, reflect the age-frequency of surface boulders, providing a record of late Holocene avalanche activity. A simulation model suggests that maximum avalanche activity affected nine of the ramparts during the 19th century, after the peak of the Little Ice Age. The pattern of avalanche activity differs from the pattern of glacier variations but is in close agreement with that of debris-flow activity. The ramparts may yield a valuable proxy record of winter snowfall. 48 refs., 12 figs., 4 tabs.

  2. Intradomicillary pre- and postfeeding behavior of Anopheles pseudopunctipennis of southern Mexico: implications for malaria control.

    PubMed

    Casas, M; Bown, D N; Rodríguez, M H

    1994-09-01

    The intradomicillary pre- and postfeed resting behavior of Anopheles pseudopunctipennis was studied in an experimental house in southern Mexico. During resting periods (both pre-/postfeed) mosquitos had greater contact (landings) with the inner roof than with the walls and other surfaces. A comparison of mean landing frequency and overall resting time (pre-/postfeed) showed that a greater periodic and prolonged contact occurred prefeed, probably as a result of disturbed activity associated with host movements. Pre-/postfeed resting patterns on walls were limited to a 0.6-0.5-m-wide band, nearly 1 m from the floor, and to a narrower band on the roof, 0.3-0.2 m wide, approximately 2.3 m from the floor, respectively. We calculated that with a band width of 0.8 m on the walls and another band 0.8 m wide on the roof, 87.2% of the mosquitoes had at least one contact with either the wall, the roof, or with both surfaces, along with an overall mean resting time (pre-/postfeed) of 8.1 min/landing. These findings suggest that a high potential for control can be achieved by spraying preferred wall and roof resting sites in this region where the intradomicillary application of residual insecticide is the primary malaria control measure. PMID:7807076

  3. Appearance of De Geer moraines in southern and western Finland - Implications for reconstructing glacier retreat dynamics

    NASA Astrophysics Data System (ADS)

    Ojala, Antti E. K.

    2016-02-01

    LiDAR digital elevation models (DEMs) from southern and western Finland were investigated to map and discriminate features of De Geer moraines, sparser and more scattered end moraines, and larger end moraine features (i.e., ice-marginal complexes). The results indicate that the occurrence and distribution of De Geer moraines and scattered end moraine ridges in Finland are more widespread than previously suggested. This is probably attributed to the ease of detecting and mapping these features with high-resolution DEMs, indicating the efficiency of LiDAR applications in geological and geomorphological studies. The variable appearance and distribution of moraine ridges in Finland support previous interpretations that no single model is likely to be appropriate for the genesis of De Geer moraines at all localities and for all types of end moraines. De Geer moraine appearances and interdistances probably result from a combination of the general rapidity of ice-margin recession during deglaciation, the proglacial water depth in which they were formed, and local glacier dynamics related to climate and terrain topography. The correlation between the varved clay-based rate of deglaciation and interdistances of distinct and regularly spaced De Geer moraine ridges indicates that the rate of deglaciation is probably involved in the De Geer ridge-forming process, but more thorough comparisons are needed to understand the extent to which De Geer interdistances represent an annual rate of ice-margin decay and the rapidity of regional deglaciation.

  4. UAVSAR and GPS Observations of Crustal Deformation in Southern California and Implications for Earthquake Risk

    NASA Astrophysics Data System (ADS)

    Donnellan, A.; Parker, J. W.; Lyzenga, G. A.; Rundle, J. B.; Grant Ludwig, L.; Granat, R. A.; Glasscoe, M. T.; Heflin, M. B.

    2010-12-01

    The 2010 El-Mayor Cucapah earthquake was the first earthquake to be observed with UAVSAR. UAVSAR observations, GPS time series analysis, and simulations suggest that the fault that ruptured in the earthquake is coupled to the Elsinore, San Jacinto, and San Andreas faults to the north. GPS and UAVSAR observations indicate a zone of shear that extends southward from the Big Bend of the San Andreas fault near Gorman through the San Fernando Valley towards the Newport-Inglewood fault. The zone steps over to the region of the Elsinore or San Jacinto faults, though the partitioning of strain between the two faults is not as clear. State changes in GPS time series data fall in line with the shear zone through the San Fernando Valley and extend northward from the El Mayor-Cucapah earthquake rupture. Seismicity hotspots also indicate elevated earthquake hazard near the San Fernando Valley and in the Inland Empire near the Elsinore and San Jacinto faults. Inversions of GPS velocity vectors favor a fault underlying the shear zone extending from the Big Bend to the Newport-Inglewood fault over substantial slip on the San Andreas fault under north of Los Angeles. Virtual California simulations of southern California are being analyzed for fault activity associated with the identified shear zone and for subsequent earthquakes that may be related to El Mayor-Cucapah type earthquakes in Baja.

  5. Seismic chimneys in the Southern Viking Graben - Implications for palaeo fluid migration and overpressure evolution

    NASA Astrophysics Data System (ADS)

    Karstens, Jens; Berndt, Christian

    2015-02-01

    Detailed understanding of natural fluid migration systems is essential to minimize risks during hydrocarbon exploration and to evaluate the long-term efficiency of the subsurface storage of waste water and gas from hydrocarbon production as well as CO2. The Southern Viking Graben (SVG) hosts numerous focused fluid flow structures in the shallow (<1000 m) subsurface. The seismic expressions of vertical fluid conduits are variously known as seismic chimneys or pipes. Seismic pipes are known to form large clusters. Seismic chimneys have so far been described as solitary structures. Here, we show that the study area in the SVG hosts more than 46 large-scale vertical chimney structures, which can be divided in three categories implying different formation processes. Our analysis reveals that seal-weakening, formation-wide overpressure and the presence of free gas are required to initiate the formation of vertical fluid conduits in the SVG. The presence of numerous vertical fluid conduits implies inter-stratigraphic hydraulic connectivity, which significantly affects the migration of fluids in the subsurface. Chimney structures are important for understanding the transfer of pore pressure anomalies to the shallow parts of the basin.

  6. Avian influenza A viruses of southern China and Hong Kong: ecological aspects and implications for man*

    PubMed Central

    Shortridge, K. F.

    1982-01-01

    Continuous surveillance of the influenza viruses isolated from domestic poultry from southern China and Hong Kong over more than 4 years resulted in the isolation of influenza viruses possessing 46 different combinations of haemagglutinin (H) and neuraminidase (N) subtypes. Of these, 43 were obtained from ducks from China. In all cases, infection appeared to be asymptomatic. The antigenic combination found most commonly in the viruses isolated was H4N6, which accounted for approximately one-quarter of the duck isolates, its occurrence being more frequent than expected from a statistical analysis of the observed frequencies of the haemagglutinin and neuraminidase genes among all the isolates. Some combinations of H and N occurred less frequently than expected or not at all. Influenza viruses tended to be isolated more frequently from ducks during the summer months in comparison with paramyxoviruses, which were more commonly encountered in the winter. Possible reasons for the great antigenic diversity of influenza A viruses in the poultry, especially the ducks, in the region are discussed together with the potential significance of these viruses to the emergence of human influenza pandemics. PMID:6979416

  7. Clinical and pharmacogenomic implications of genetic variation in a Southern Ethiopian population.

    PubMed

    Tekola-Ayele, F; Adeyemo, A; Aseffa, A; Hailu, E; Finan, C; Davey, G; Rotimi, C N; Newport, M J

    2015-02-01

    Africa is home to genetically diverse human populations. We compared the genetic structure of the Wolaita ethnic population from Southern Ethiopia (WETH, n=120) with HapMap populations using genome-wide variants. We investigated allele frequencies of 443 clinically and pharmacogenomically relevant genetic variants in WETH compared with HapMap populations. We found that WETH were genetically most similar to the Kenya Maasai and least similar to the Japanese in HapMap. Variant alleles associated with increased risk of adverse reactions to drugs used for treating tuberculosis (rs1799929 and rs1495741 in NAT2), thromboembolism (rs7294, rs9923231 and rs9934438 in VKORC1), and HIV/AIDS and solid tumors (rs2242046 in SLC28A1) had significantly higher frequencies in WETH compared with African ancestry HapMap populations. Our results illustrate that clinically relevant pharmacogenomic loci display allele frequency differences among African populations. We conclude that drug dosage guidelines for important global health diseases should be validated in genetically diverse African populations. PMID:25069476

  8. Holocene Pacific - North American plate interaction in southern Alaska: implications for the Yakataga seismic gap.

    USGS Publications Warehouse

    Lahr, J.C.; Plafker, G.

    1980-01-01

    The St. Elias, Alaska, earthquake (magnitude 7.1 MS) on February 28, 1979, occurred along the complex Pacific-North American plate boundary between Yakutat Bay and Prince William Sound, rupturing only a fraction of the seismic gap identified in that region. To aid in evaluating the potential for, and likely site of, a future earthquake occurring in the remainder of the gap, we have formulated a kinematic model of neotectonic deformation in southern Alaska from available geologic and seismic data. In this model the part of the North American plate bordering on the Gulf of Alaska is divided into three subblocks, which are partially coupled to the Pacific plate. On the basis of the model, the gap-filling rupture or ruptures would most likely be along the north-dipping thrust faults of the Pamplona zone between Icy Bay and the eastern end of the Aleutian Trench. If the accumulated strain of 3.8 m postulated for this region were released suddenly in one event involving the remainder of the gap, the result would be an earthquake as large as magnitude 8. -Authors

  9. Prediction of temperature and precipitation in Sudan and South Sudan by using LARS-WG in future

    NASA Astrophysics Data System (ADS)

    Chen, Hua; Guo, Jiali; Zhang, Zengxin; Xu, Chong-Yu

    2013-08-01

    Global warming has brought great pressure on the environment and livelihood conditions in Sudan and South Sudan. It is desirable to analyze and predict the change of critical climatic variables, such as temperature and precipitation, which will provide valuable reference results for future water resources planning and management in the region. The aims of this study are to test the applicability of the Long Ashton Research Station Weather Generator (LARS-WG) model in downscaling daily precipitation and daily maximum (Tmax) and daily minimum (Tmin) temperatures in Sudan and South Sudan and use it to predict future changes of precipitation; Tmin and Tmax for nine stations in Sudan and South Sudan are based on the SRA2 scenario of seven General Circulation Models (GCMs) outputs for the periods of 2011-2030, 2046-2065, and 2080-2099. The results showed that (1) the LARS-WG model produces good performance in downscaling daily precipitation and excellent performance in downscaling Tmax and Tmin in the study region; (2) downscaled precipitation from the prediction of seven GCMs showed great inconsistency in these two regions, which illustrates the great uncertainty in GCMs' results in the regions; (3) predicted precipitation in rainy season JJA (June, July, and August) based on the ensemble mean of seven GCMs showed a decreasing trend in the periods of 2011-2030, 2046-2065, and 2080-2099 in Sudan; however, an increasing trend can be found in SON (September, October, and November) in the future; (4) precipitation in South Sudan has an increasing trend in most seasons in the future except in MAM (March, April, and May) season in 2011-2030; and (5) predictions from seven GCMs showed a similar and continuous increasing trend for Tmax and Tmin in all three future periods, which will bring severe negative influence on improving livelihoods and reducing poverty in Sudan and South Sudan.

  10. Anthocyanins of Hibiscus sabdiffera calyces from Sudan.

    PubMed

    Cahliková, Lucie; Ali, Badreldin H; Havliková, Lucie; Ločárek, Mirek; Siatka, Tomáš; Opletal, Lubomir; Blunden, Gerald

    2015-01-01

    Extracts of the calyces of Hibiscus sabdariffa are widely used in folk medicine to combat many illnesses. The active constituents of the extracts have been shown on several occasions to be anthocyanins. In our current studies the biological activities of an extract of H. sabdariffa calyces purchased in Oman, but grown in Sudan, are being compared with those of the anthocyanins isolated from them, and, for this, the anthocyanin profile of the extract needed to be ascertained. Although several anthocyanins were detected by UHPLC-ESI-MS/MS, delphinidin-3-sambubioside (major) and cyanidin-3-sambubioside were predominant. PMID:25920224

  11. Dracunculiasis Eradication: And Now, South Sudan

    PubMed Central

    Hopkins, Donald R.; Ruiz-Tiben, Ernesto; Weiss, Adam; Withers Jr., P. Craig; Eberhard, Mark L.; Roy, Sharon L.

    2013-01-01

    This report summarizes the status of the global Dracunculiasis Eradication Program as of the end of 2012. Dracunculiasis (Guinea worm disease) has been eliminated from 17 of 21 countries where it was endemic in 1986, when an estimated 3.5 million cases occurred worldwide. Only 542 cases were reported from four countries in 2012, and 103 villages still had indigenous transmission. Most remaining cases were reported from the new Republic of South Sudan, whereas Chad, Ethiopia, and Mali each reported 10 cases or less. Political instability and insecurity in Mali may become the main obstacles to interrupting dracunculiasis transmission forever. PMID:23843492

  12. The Impact of Fire on Energy Balance in Southern African Savanna Ecosystems: Implications of Climate Change

    NASA Astrophysics Data System (ADS)

    Dintwe, K.; Okin, G. S.; Saha, M.; Scanlon, T. M.; D'Odorico, P.; De Sales, F.; Xue, Y.

    2015-12-01

    Savannas are the most fire prone ecosystems in the world accounting for more than 75% of annual global fires. Wildfires in savannas consume large quantities of biomass releasing CO2 and aerosols while leaving ash and char residues. The residues form black-grey patches on the soil surface, and together with newly exposed bare soil patches, they play a significant role in altering surface reflectance and vegetation condition. We investigated the impact of fire on savanna albedo and vegetation greenness (from Enhanced Vegetation Index, EVI) from 2000-2014 using data from the Moderate Resolution Imaging Spectrometer (MODIS) for Africa south of the Equator. Preliminary results indicate that more mesic savannas near the Equator have the highest fire frequencies, with fire frequency generally decreasing with aridity. Immediately after fires, the average change in albedo and EVI is -5% and -10%, respectively, with the magnitude of the change increasing with aridity. The time for albedo to recover to values similar to unburned areas varied by latitude, with more mesic savannas recovering much faster (24 days vs. 65 days for dry savannas). The time for vegetation condition to recover did not vary strongly by latitude (about 65 days). The upward shortwave energy in burnt areas in mesic savannas is 53 W m-2 compared to 95 W m-2 for unburnt areas, indicating a positive forcing of about 42 W m-2 associated with mesic savanna fires locally. Approximately 7% of the (primarily savanna) land in southern Africa burns each year, suggesting an overall forcing in Africa south of the Equator of ~1-2 W m-2 associated with savanna fires. This large forcing indicates clearly the important interplay between ecosystem processes (fire) and climate (radiative forcing) in this region. With changing climate, this region is expected to become significantly drier, suggesting that the forcing due to fire might decrease in the coming decades and indicating that fire-induced albedo changes potentially

  13. Floristic Relationships Among Vegetation Types of New Zealand and the Southern Andes: Similarities and Biogeographic Implications

    PubMed Central

    Ezcurra, Cecilia; Baccalá, Nora; Wardle, Peter

    2008-01-01

    Background and Aims Similarities between the floras of geographically comparable regions of New Zealand (NZ) and the southern Andes (SA) have interested biologists for over 150 years. The present work selects vegetation types that are physiognomically similar between the two regions, compares their floristic composition, assesses the environmental factors that characterize these matching vegetation types, and determines whether phylogenetic groups of ancestral versus modern origin are represented in different proportions in their floras, in the context of their biogeographic history. Methods Floristic relationships based on 369 genera of ten vegetation types present in both regions were investigated with correspondence analysis (CA) and ascending hierarchical clustering (AHC). The resulting ordination and classification were related to the environmental characteristics of the different vegetation types. The proportions of different phylogenetic groups between the regions (NZ, SA) were also compared, and between forest and non-forest communities. Key Results Floristic similarities between NZ and SA tend to increase from forest to non-forest vegetation, and are highest in coastal vegetation and bog. The floras of NZ and SA also differ in their phylogenetic origin, NZ being characterized by an ‘excess’ of genera of basal origin, especially in forests. Conclusions The relatively low similarities between forests of SA and NZ are related to the former being largely of in situ South American and Gondwanan origin, whereas the latter have been mostly reconstituted though transoceanic dispersal of propagules since the Oligocene. The greater similarities among non-forest plant communities of the two regions result from varied dispersal routes, including relatively recent transoceanic dispersal for coastal vegetation, possible dispersal via a still-vegetated Antarctica especially for bog plants, and independent immigration from Northern Hemisphere sources for many genera

  14. Shear wave velocity mapping of Hat Yai district, southern Thailand: implication for seismic site classification

    NASA Astrophysics Data System (ADS)

    Yordkayhun, Sawasdee; Sujitapan, Chedtaporn; Chalermyanont, Tanit

    2015-02-01

    Soil characteristics play an important role in the degree of ground shaking due to local site amplification during an earthquake. The objectives of this work are to study shear wave velocity (Vs) distribution in the near surface, and to develop a seismic site classification map for soil effect characterization and seismic hazard assessment in Hat Yai district, southern Thailand. The Vs determination based on the multichannel analysis of surface waves technique, has been carried out and analyzed at 70 measuring sites throughout the district. On the basis of the weighted-average Vs in the upper 30 m depth (Vs30), a seismic site classification map, based on the National Earthquake Hazards Reduction Program (NEHRP) standard has been developed. It is found that the NEHRP site class in Hat Yai can be classified into four groups in accordance with the value of Vs30 within the range of about 150 to 1160 m s-1. Most parts of the study area are typically classified as site class C and D. Site class C is mostly found within the colluvial and terrace deposits in the western and eastern part of the area, whereas site class D is concentrated in the alluvial sediment of the middle and northern flood plain areas. A small portion of site class B is observed in the western mountain ranges, where there is a thin overburden on the firm rock. There is a remarkably low Vs30 value at only one site, located near the main stream in the northern part of the study area. The results imply that the soil characteristics in the central and northern Hat Yai district pose a medium to high amplification rate with respect to the other regions. Although Vs data alone are insufficient to verify the potential of the amplification of ground shaking, this study provides an initial attempt to understand seismic hazards in the study area.

  15. Variability of the Southern California wave climate and implications for sediment transport

    USGS Publications Warehouse

    Xu, J. P.; Noble, M.A.

    2009-01-01

    We analyzed wave and wind data from 18 buoys in the Southern California Bight to characterize the spatial and temporal variability of the regional wave climate. Point Conception shelters most of the Bight from being directly impacted by North Pacific weather. The wave height inside the sheltered zone and to the east of the Channel Islands is less than half the wave height in the open ocean to the west. Within the sheltered Bight, storm waves (by proxy of being greater than the 95th percentile wave height for more than 6 hours) are mainly from the west, but long period swells (Tp >15 seconds) are mainly from the south-southwest. There are on average two to four storms during each winter month (November-March) and fewer than two storms per month for the rest of the year. The Channel Islands selectively block the westerly swells and make the wave climate in the Santa Barbara Channel different from the rest of the sheltered Bight. A statistically significant wave-height minimum exists in the area offshore Dana Point and Oceanside. The multiyear (2-23 years) wave-data records from all 18 buoys show negligible temporal trend, positive or negative. Like the wave climate, the long-term probability of sediment transport on the continental shelves of the Bight displays large difference between the sheltered and open-ocean (near Point Conception) sites. The return period of incipient sediment motion on the sheltered shelf breaks (one to five months) is at least two orders of magnitude longer than that on the Point Conception shelf break (0.6 day). Similar to the spatial distribution of wave heights, there is a systematic return-period maximum on the shelf off Dana Point and Oceanside. ?? 2009 The Geological Society of America.

  16. Geochemical characterization of a Holocene aeolian profile in the Zhongba area (southern Tibet, China) and its paleoclimatic implications

    NASA Astrophysics Data System (ADS)

    Li, Tuoyu; Wu, Yongqiu; Du, Shisong; Huang, Wenmin; Hao, Chengzhi; Guo, Chao; Zhang, Mei; Fu, Tianyang

    2016-03-01

    The Zhongba area lies in the valley of the Maquan River in southern Tibet, where there are both strong modern aeolian activities and ancient aeolian sand sediments. A Holocene aeolian sand and paleosol profile in the Zhongba area was selected for study and termed (Zhuzhu (ZZ) profile). The chronology of the ZZ profile was established by optically stimulated luminescence (OSL) and accelerator mass spectrometry (AMS) 14C dating. Based on the grain size and geochemical elements of the ZZ profile, the geochemical characterization was analyzed, the Holocene aeolian activity processes were reconstructed in the study area, and the paleoclimatic implications were discussed. The major elements and the chemical indicators are highly correlated with different grain-sizes in the ZZ profile. The evolutionary sequence of the aeolian activities and the paleoclimate in Holocene reveal four stages: before 7.3 ka BP, the climate was warm and wet with weak winds when the sand paleosol developed; at 7.3-3.8 ka BP, the climate turned dry, with strong aeolian activities; at 3.8-0.7 ka BP, the climate became wetter and the winds weakened when the silt paleosol developed; and since 0.7 ka BP, it was cold and dry with strong aeolian activities.

  17. Genetic variation in insecticide tolerance in a population of southern leopard frogs (Rana sphenocephala): Implications for amphibian conservation

    USGS Publications Warehouse

    Bridges, C.M.; Semlitsch, R.D.

    2001-01-01

    Currently, conservation efforts are devoted to determining the extent and the causes of the decline of many amphibian species worldwide. Human impacts frequently degrade amphibian habitat and have been implicated in many declines. Because genetic variance is critical in determining the persistence of a species in a changing environment, we examined the amount of genetic variability present in a single population for tolerance to an environmental stressor. We examined the amount of genetic variability among full- and half-sib families in a single population of southern leopard frogs (Rana sphenocephala) with respect to their tolerance to lethal concentrations of the agricultural chemical, carbaryl. Analysis of time-to-death data indicated significant differences among full-sib families and suggests a large amount of variability present in the responses to this environmental stressor. Significant differences in responses among half-sib families indicated that there is additive genetic variance. These data suggest that this population may have the ability to adapt to environmental stressors. It is possible that declines of amphibian populations in the western United States may be attributed to low genetic variability resulting from limited migration among populations and small population sizes.

  18. Trachoma in the Sudan. An epidemiological study.

    PubMed Central

    Salim, A R; Sheikh, H A

    1975-01-01

    The prevalence and distribution of trachoma in the Sudan has been studied. The morbidity rate of 83.2 per 1000 in the Northern Province decreases southwards until it reaches 0.94 in the extreme south (Equatoria Province). 2. In endemic areas infection starts very early--in the first year of life. 3. There is a marked difference between the prevalence of trachoma in towns and villages--71.3 per cent for the age group 1-4 years in villages, and 56.7 per cent for the same age group in the towns. This is probably due to better standards of living and hygiene in the towns. 4. Some relationship has been found between the rainfall, the relative humidity, and the incidence of trachoma, but this does not necessarily apply in other countries. 5. The factors that may explain the high prevalence of trachoma in the northern Sudan are: a. Mechanical trauma caused by frequent sandstorms. b. Irritation of the eyes by dust particles, leading to excessive watering and discharge, and rubbing with the fingers. c. The habit of frequent hand-shaking. d. Poor personal hygiene in pre-schoolchildren. e. Associated bacterial conjunctivitis. f. The presence of eye-seeking flies. PMID:1191619

  19. Southern hemisphere sand furrows: spatial patterning and implications for the cryo-venting process.

    NASA Astrophysics Data System (ADS)

    Nash, Ciaran; Bourke, Mary

    2015-04-01

    Carbon dioxide is an important volatile on Mars. Seasonally, atmospheric CO2 condenses as ice on to the Martian surface and sublimates during the spring. Links have been made between a suite of observed surface features and the sublimation of surface CO2 ice; these include spider-like araneiform, gullies, and fans. Sand furrows are one such feature; suggested to form due to the erosive action of pressurised CO2 gas as it escapes through cracks in surficial ice (i.e. cryo-venting, Bourke, 2013). There are significant and important differences between the North and South Hemispheres, particularly in the seasonal CO2 deposits. Previous investigations into the formation and distribution of sand furrows on Mars have concentrated solely on the northern hemisphere. We present a study of furrows in the southern hemisphere which has yielded new data on their distribution and spatial patterning as well as providing insights into the cryo-venting process. A total of 221 dune sites were surveyed over the three Martian years' of available HiRISE data to establish the overall distribution of sand furrows. A more detailed study was carried out at eight sites using data from Mars Year 30. These sites represent a latitudinal sample of dunefields located between 40°S to 72°S. Surficial CO2 ice thickness was estimated using the Mars Climate Database (Millour et al., 2014). Our data show that sand furrows are significantly less numerous in the study region than in the northern hemisphere where data show they occur in 95% of surveyed sites. We found a strong correlation between latitude and furrow distribution. As one progresses polewards from 40°S, furrows become more numerous until 68°S. Furrows were not detected south of 72°S. Carbon dioxide ice thickness has been highlighted as a potentially important factor controlling furrow distribution in the northern hemisphere (Bourke and McGaley-Towle, 2014). Results from our investigation suggest there is a feedback mechanism between

  20. Varena suite in the crystalline crust of the Southern Lithuania: implication to the genesis and mineralization

    NASA Astrophysics Data System (ADS)

    Kirkliauskaite, Vaida; Motuza, Gediminas; Skipityte, Raminta

    2016-04-01

    Keywords: Lithuania, Proterozoic, Varena suite, rare earth elements, metasomatosis. Crystalline crust in Southern Lithuania is covered by 200-500 m thick sedimentary cover and is investigated by potential field mapping and drilling. It is composed by amphibolites (metabasalts), biotite-quartz-plagioclase gneisses (metapsammites and porphyry metadacite and metaandesite) of Orosirian period. Each lithology is predominant in alternating bands extended NNE-SSW. Supracrustals are metamorphosed on the level of amphibolite facies and migmatized. Intrusive rocks are represented by coeval rare bodies of gabbro, peridotite and widespread Calymmian granitic plutons. Varena suite comprises olivine, enstatite, diopside, olivine-magnetite, magnetite, apatite-bearing, and presumably also dolomite rocks. They form integrated bodies few sq. km large, concentrated in the ˜300 km2area extended in N-S direction.Bodies of particular rocks from Varena suite fixed in the boreholes are few tenths up to few hundred meters thick, except apatite-bearing rocks, forming decimeter up to meter scale lenses and veins. Rocks of Varena suite are affected by strong metasomatic alteration. Olivine is substituted by serpentine, and phlogopite, pyroxenes with amphibols (hornblende, actinolite, tremolite, rarely richterite). The country rocks (amphibolites, metaporphyres) also affected by alkaline (mainly sodic) metasomatosis manifested by formation of scapolite, albite, clynopyroxene (often sodic), phlogopite, carbonates. The mineralization of REE (up to 2759-3100 ppm of La and Ce respectively), Th, U, P hosted by monazite, apatite, allanite is spatially related to the Varena suite and some metasomatized supracrustals. The views on the genesis of Varena suite are contradicting. By various authors they are regarded as skarns, presuming metasomatic origin, as layered intrusions or products of alkaline and carbonatitic magmatism. In this presentation the genetic model is reviewed based on

  1. A sediment budget for the southern reach in San Francisco Bay, CA: implications for habitat restoration

    USGS Publications Warehouse

    Shellenbarger, Gregory; Wright, Scott A.; Schoellhamer, David H.

    2013-01-01

    The South Bay Salt Pond Restoration Project is overseeing the restoration of about 6000 ha of former commercial salt-evaporation ponds to tidal marsh and managed wetlands in the southern reach of San Francisco Bay (SFB). As a result of regional groundwater overdrafts prior to the 1970s, parts of the project area have subsided below sea-level and will require between 29 and 45 million m3 of sediment to raise the surface of the subsided areas to elevations appropriate for tidal marsh colonization and development. Therefore, a sufficient sediment supply to the far south SFB subembayment is a critical variable for achieving restoration goals. Although both major tributaries to far south SFB have been seasonally gaged for sediment since 2004, the sediment flux at the Dumbarton Narrows, the bayward boundary of far south SFB, has not been quantified until recently. Using daily suspended-sediment flux data from the gages on Guadalupe River and Coyote Creek, combined with continuous suspended-sediment flux data at Dumbarton Narrows, we computed a sediment budget for far south SFB during Water Years 2009–2011. A Monte Carlo approach was used to quantify the uncertainty of the flux estimates. The sediment flux past Dumbarton Narrows from the north dominates the input to the subembayment. However, environmental conditions in the spring can dramatically influence the direction of springtime flux, which appears to be a dominant influence on the net annual flux. It is estimated that up to several millennia may be required for natural tributary sediments to fill the accommodation space of the subsided former salt ponds, whereas supply from the rest of the bay could fill the space in several centuries. Uncertainty in the measurement of sediment flux is large, in part because small suspended-sediment concentration differences between flood and ebb tides can lead to large differences in total mass exchange. Using Monte Carlo simulations to estimate the random error associated with

  2. Identifying potential sources of Sudan I contamination in Capsicum fruits over its growth period.

    PubMed

    Wu, Naiying; Gao, Wei; Zhou, Li; Lian, Yunhe; Li, Fengfei; Han, Wenjie

    2015-04-15

    Sudan dyes in spices are often assumed to arise from cross-contamination or malicious addition. Here, experiments were carried out to identify the potential source of Sudan I-IV in Capsicum fruits through investigation of their contents in native Capsicum tissues, soils and associated agronomic materials. Sudan II-IV was not detected in any of the tested samples. Sudan I was found in almost all samples except for the mulching film. Sudan I concentrations decreased from stems to leaves and then to fruits or roots. Sudan I levels in soils were significantly elevated by vegetation treatment. These results exclude the possibility of soil as the main source for Sudan I contamination in Capsicum fruits. Further study found out pesticide and fertilizer constitutes the major source of Sudan I contamination. This work represents a preliminary step for a detailed Sudan I assessment to support Capsicum management and protection in the studied region. PMID:25466000

  3. Islands of Education: Schooling, Civil War and the Southern Sudanese (1983-2004)

    ERIC Educational Resources Information Center

    Sommers, Marc

    2005-01-01

    Victims of warfare, famine, slavery, and isolation, the Southern Sudanese are one of the most undereducated populations in the world. Since the inception of formal education in southern Sudan a century ago, schooling has largely consisted of island-like entities surrounded by oceans of educational emptiness. Islands of Education is the first book…

  4. Work-Oriented Adult Literacy Project in the Sudan

    ERIC Educational Resources Information Center

    Sammak, A.

    1971-01-01

    Discusses the illiteracy problem and the adult literacy program undertaken by the government of the Sudan. In addition, it describes a survey undertaken to discover the main shortcomings and mistakes of the labor force which could be corrected. (AN)

  5. Exploitation and recovery of a sea urchin predator has implications for the resilience of southern California kelp forests

    PubMed Central

    Hamilton, Scott L.; Caselle, Jennifer E.

    2015-01-01

    Size-structured predator–prey interactions can be altered by the history of exploitation, if that exploitation is itself size-selective. For example, selective harvesting of larger sized predators can release prey populations in cases where only large individuals are capable of consuming a particular prey species. In this study, we examined how the history of exploitation and recovery (inside marine reserves and due to fisheries management) of California sheephead (Semicossyphus pulcher) has affected size-structured interactions with sea urchin prey in southern California. We show that fishing changes size structure by reducing sizes and alters life histories of sheephead, while management measures that lessen or remove fishing impacts (e.g. marine reserves, effort restrictions) reverse these effects and result in increases in density, size and biomass. We show that predation on sea urchins is size-dependent, such that the diet of larger sheephead is composed of more and larger sized urchins than the diet of smaller fish. These results have implications for kelp forest resilience, because urchins can overgraze kelp in the absence of top-down control. From surveys in a network of marine reserves, we report negative relationships between the abundance of sheephead and urchins and the abundance of urchins and fleshy macroalgae (including giant kelp), indicating the potential for cascading indirect positive effects of top predators on the abundance of primary producers. Management measures such as increased minimum size limits and marine reserves may serve to restore historical trophic roles of key predators and thereby enhance the resilience of marine ecosystems. PMID:25500572

  6. Alkaline pulping of some eucalypts from Sudan.

    PubMed

    Khristova, P; Kordsachia, O; Patt, R; Dafaalla, S

    2006-03-01

    Four eucalypts (Eucalyptus camaldulensis, Eucalyptus microtheca, Eucalyptus tereticornis and Eucalyptus citriodora) grown in Sudan were examined for their suitability for pulping and papermaking with different alkaline methods. Their physical, morphological and chemical characteristics are reported. The pulping trials with E. citriodora and E. tereticornis were carried out using the kraft-AQ, soda-AQ, modified AS/AQ (ASA), ASAM and kraft methods. For the other two species, only the ASAM and the kraft process were applied. ASAM pulping gave the best results in terms of yield, degree of delignification, mechanical and optical pulp properties. The best pulps, obtained in kraft and ASAM cooking of E. citriodora, were bleached to 88% ISO brightness in a totally chlorine free bleaching sequence (OQ1O/PQ2P). The bleached pulps, especially the ASAM pulp, showed good papermaking properties and would be suitable for manufacture of writing and printing grades of paper. PMID:15935655

  7. Application of Raman spectroscopy technology to studying Sudan I

    NASA Astrophysics Data System (ADS)

    Li, Gang; Zhang, Guoping; Chen, Chen

    2006-06-01

    Being an industrial dye, the Sudan I may have a toxic effect after oral intake on the body, and has recently been shown to cause cancer in rats, mice and rabbits. Because China and some other countries have detected the Sudan I in samples of the hot chilli powder and the chilli products, it is necessary to study the characteristics of this dye. As one kind of molecule scattering spectroscopy, Raman spectroscopy is characterized by the frequency excursion caused by interactions of molecules and photons. The frequency excursion reflects the margin between certain two vibrational or rotational energy states, and shows the information of the molecule. Because Raman spectroscopy can provides quick, easy, reproducible, and non-destructive analysis, both qualitative and quantitative, with no sample preparation required, Raman spectroscopy has been a particularly promising technique for analyzing the characteristics and structures of molecules, especially organic ones. Now, it has a broad application in biological, chemical, environmental and industrial applications. This paper firstly introduces Sudan I dye and the Raman spectroscopy technology, and then describes its application to the Sudan I. Secondly, the fingerprint spectra of the Sudan I are respectively assigned and analyzed in detail. Finally, the conclusion that the Raman spectroscopy technology is a powerful tool to determine the Sudan I is drawn.

  8. Determining the effect of climate change and development on water resources management in the Sudan

    NASA Astrophysics Data System (ADS)

    Satti, S.; Zaitchik, B.; Siddiqui, S.

    2013-12-01

    The effects of development and the uncertainty of climate change in East Africa provide a myriad of challenges for water managers along the Blue Nile. The construction of the Grand renaissance dam (GRD), as well as the unknown trajectory of precipitation trends in the Ethiopian highlands may greatly affect the countries that rely on the Nile. Sudan's huge irrigation potential and dams that feed multiple current irrigation schemes as well as its location within the basin means that Sudan's water management decisions may reverberate and have social, economic and political implications within the east African sub-region. Here, we apply a suite of state-of-the-art hydrology and climate analysis tools to evaluate the sensitivity of Sudan's optimal hydropower and irrigation development pathways to hydrologic variability and climate change. Present day hydrologic conditions are derived from a gridded implementation of the Noah Land Surface Model (LSM) that includes representation of typical irrigation practices in the region. Noah is implemented using the NASA Land Information System (LIS), and draws forcing data from a combination of reanalysis and satellite meteorological products. Additional satellite inputs are used to provide a constraint on Noah evapotranspiration estimates and to acquire parameters such as crop water requirements that are crucial in determining yield and agricultural production. Future climate conditions are projected using statistical downscaling techniques trained to historical meteorological records and projected forward using inputs from the 5th Coupled Model Intercomparison Project (CMIP5) simulation database. These climatic and hydrologic inputs are combined with agronomic and economic inputs to drive an optimization model developed within the General Algebraic Modeling System (GAMS). By using output and results from climate, hydrologic and optimization models this research aims to show how these models can be integrated to aid decision

  9. Development of sedimentary cycles on the east Sahara craton since Silurian time (northwest Sudan/southwest Egypt)

    SciTech Connect

    Wycisk, P. )

    1988-08-01

    The sedimentary succession of southwest Egypt and northwest Sudan, formerly called the Nubia(n) Sandstone, has been subdivided into a number of formations. The predominantly fluvial sediments which characterize Silurian to Upper Cretaceous strata of this region were repeatedly interrupted by marine transgressions that rapidly progressed toward the south since Ordovician time. Thin, shallow marine sequences of different ages can be traced for more than 1,000 km within the studied area. The development of the sedimentary cycles will be pointed out by surface and subsurface data along a cross section from the southern Dakhla basin in the north to the Misaha trough and Abyad basin in the south.

  10. Morphological Analysis of Apo Volcanic Complex in Southern Mindanao, Philippines: implications on volcano-tectonic evolution of different volcanic units

    NASA Astrophysics Data System (ADS)

    Herrero, T. M. L.; van Wyk de Vries, B.; Lagmay, A. M. A.; Eco, R. C.

    2015-12-01

    The Apo Volcanic Complex (AVC) is one of the largest volcanic centers in the Philippines, located in the southern island of Mindanao. It is composed of four edifices and several smaller cones. The youngest volcanic unit, the Apo Dome, is the highest elevation in the Philippines. This unit is classified as potentially active, whereas other units, Talomo, Sibulan and Kitubod, are inactive. The study gives insight to the construction and deformation history of the volcanic units and imparts foresight to subsequent events that can affect populated areas. A morphological analysis integrating high-resolution digital terrain models and public domain satellite data and images was done to recognize and discriminate volcanic units and characterize volcano-tectonic features and processes. Morphological domains were defined based on surface textures, slope variation, degrees and controls of erosion, and lineament density and direction. This establishes the relative ages and extent of volcanic units as well as the volcano-tectonic evolution of the complex. Six edifice building events were recognized, two of which form the elevated base of Apo dome. The geodynamic setting of the region is imprinted in the volcanic units as five morphostructural lineaments. They reveal the changes in maximum regional stress through time such as the N-S extension found across the whole volcanic complex displaying the current stress regime. This has implications on the locality and propagation of geothermal activity, magma ascent, and edifice collapses. One main result of the compounded effects of inherited structures and current stress regime is the Sandawa Collapse Zone. This is a large valley formed by several collapses where NE-SW fractures propagate and the increasing lateral spreading by debuttressing continue to eat away the highest peak. The AVC is surrounded by the major metropolitan area of Davao City to the east and the cities of Kidapawan and Digos to the west and south, respectively

  11. 31 CFR 538.209 - Prohibited transportation-related transactions involving Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... transactions involving Sudan. 538.209 Section 538.209 Money and Finance: Treasury Regulations Relating to Money... SANCTIONS REGULATIONS Prohibitions § 538.209 Prohibited transportation-related transactions involving Sudan... relating to transportation of cargo to or from Sudan; (b) The provision of transportation of cargo to...

  12. 3 CFR - Continuation of the National Emergency With Respect to Sudan

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... to Sudan Presidential Documents Other Presidential Documents Notice of November 1, 2012 Continuation of the National Emergency With Respect to Sudan On November 3, 1997, by Executive Order 13067, the President declared a national emergency with respect to Sudan and, pursuant to the International...

  13. 3 CFR - Continuation of the National Emergency With Respect to Sudan

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... to Sudan Presidential Documents Other Presidential Documents Notice of November 1, 2011 Continuation of the National Emergency With Respect to Sudan On November 3, 1997, by Executive Order 13067, the President declared a national emergency with respect to Sudan, pursuant to the International...

  14. 31 CFR 538.532 - Humanitarian transshipments to or from the Specified Areas of Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the Specified Areas of Sudan. 538.532 Section 538.532 Money and Finance: Treasury Regulations Relating... Humanitarian transshipments to or from the Specified Areas of Sudan. The transit or transshipment to or from the Specified Areas of Sudan of goods, technology, or services intended for humanitarian...

  15. 31 CFR 538.532 - Humanitarian transshipments to or from the Specified Areas of Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the Specified Areas of Sudan. 538.532 Section 538.532 Money and Finance: Treasury Regulations Relating... Humanitarian transshipments to or from the Specified Areas of Sudan. The transit or transshipment to or from the Specified Areas of Sudan of goods, technology, or services intended for humanitarian...

  16. 3 CFR - Continuation of the National Emergency With Respect to Sudan

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... to Sudan Presidential Documents Other Presidential Documents Notice of November 1, 2010 Continuation of the National Emergency With Respect to Sudan On November 3, 1997, by Executive Order 13067, the President declared a national emergency with respect to Sudan, pursuant to the International...

  17. 31 CFR 538.205 - Prohibited exportation and reexportation of goods, technology, or services to Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... reexportation of goods, technology, or services to Sudan. 538.205 Section 538.205 Money and Finance: Treasury... goods, technology, or services to Sudan. Except as otherwise authorized, the exportation or reexportation, directly or indirectly, to Sudan of any goods, technology (including technical data, software,...

  18. 31 CFR 538.205 - Prohibited exportation and reexportation of goods, technology, or services to Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... reexportation of goods, technology, or services to Sudan. 538.205 Section 538.205 Money and Finance: Treasury... goods, technology, or services to Sudan. Except as otherwise authorized, the exportation or reexportation, directly or indirectly, to Sudan of any goods, technology (including technical data, software,...

  19. 3 CFR - Continuation of the National Emergency With Respect to Sudan

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... to Sudan Presidential Documents Other Presidential Documents Notice of October 30, 2013 Continuation of the National Emergency With Respect to Sudan On November 3, 1997, by Executive Order 13067, the President declared a national emergency with respect to Sudan and, pursuant to the International...

  20. 31 CFR 538.205 - Prohibited exportation and reexportation of goods, technology, or services to Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... reexportation of goods, technology, or services to Sudan. 538.205 Section 538.205 Money and Finance: Treasury... goods, technology, or services to Sudan. Except as otherwise authorized, the exportation or reexportation, directly or indirectly, to Sudan of any goods, technology (including technical data, software,...

  1. 31 CFR 538.209 - Prohibited transportation-related transactions involving Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... transactions involving Sudan. 538.209 Section 538.209 Money and Finance: Treasury Regulations Relating to Money... SANCTIONS REGULATIONS Prohibitions § 538.209 Prohibited transportation-related transactions involving Sudan... relating to transportation of cargo to or from Sudan; (b) The provision of transportation of cargo to...

  2. 31 CFR 538.209 - Prohibited transportation-related transactions involving Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... transactions involving Sudan. 538.209 Section 538.209 Money and Finance: Treasury Regulations Relating to Money... SANCTIONS REGULATIONS Prohibitions § 538.209 Prohibited transportation-related transactions involving Sudan... relating to transportation of cargo to or from Sudan; (b) The provision of transportation of cargo to...

  3. 31 CFR 538.532 - Humanitarian transshipments to or from the Specified Areas of Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the Specified Areas of Sudan. 538.532 Section 538.532 Money and Finance: Treasury Regulations Relating... Humanitarian transshipments to or from the Specified Areas of Sudan. The transit or transshipment to or from the Specified Areas of Sudan of goods, technology, or services intended for humanitarian...

  4. 31 CFR 538.209 - Prohibited transportation-related transactions involving Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... transactions involving Sudan. 538.209 Section 538.209 Money and Finance: Treasury Regulations Relating to Money... SANCTIONS REGULATIONS Prohibitions § 538.209 Prohibited transportation-related transactions involving Sudan... relating to transportation of cargo to or from Sudan; (b) The provision of transportation of cargo to...

  5. 31 CFR 538.205 - Prohibited exportation and reexportation of goods, technology, or services to Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... reexportation of goods, technology, or services to Sudan. 538.205 Section 538.205 Money and Finance: Treasury... goods, technology, or services to Sudan. Except as otherwise authorized, the exportation or reexportation, directly or indirectly, to Sudan of any goods, technology (including technical data, software,...

  6. Space Radar Image of Sudan Collision Zone

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This is a radar image of a region in northern Sudan called the Keraf Suture that reveals newly discovered geologic features buried beneath layers of sand. This discovery is being used to guide field studies of the region and has opened up new perspectives on old problems, such as what controls the course of the Nile, a question that has perplexed geologists for centuries. The Nile is the yellowish/green line that runs from the top to the bottom of the image. A small town, Abu Dis, can be seen as the bright, white area on the east (right) bank of the Nile (about a third of the way down from the top) at the mouth of a dry stream valley or 'wadi' that drains into the river. Wadis flowing into the Nile from both east and west stand out as dark, reddish branch-like drainage patterns. The bright pink area on the west (left) side of the Nile is a region where rocks are exposed, but the area east (right) of the Nile is obscured by layers of sand, a few inches to several feet thick. Virtually everything visible on the right side of this radar image is invisible when standing on the ground or when viewing photographs or satellite images such as the United States' Landsat or the French SPOT satellite. A sharp, straight fault cuts diagonally across the image, to the right of the Nile river. The area between the fault and the Nile is part of the collision zone where the ancient continents of East and West Gondwana crashed into each other to form the supercontinent Greater Gondwana more than 600 million years ago. On this image, the Nile approaches but never crosses the fault, indicating that this fault seems to be controlling the course of the Nile in this part of Sudan. The image is centered at 19.5 degrees north latitude, 33.35 degrees east longitude, and shows an area approximately 18 km by 20 km (10 miles by 12 miles). The colors in the image are assigned to different frequencies and polarizations of the radar as follows: Red is L-band, vertically transmitted and vertically

  7. VOLATILE ORGANIC COMPOUNDS FROM VEGETATION IN SOUTHERN YUNNAN PROVINCE, CHINA: EMISSION RATES AND SOME POTENTIAL REGIONAL IMPLICATIONS

    EPA Science Inventory

    Little information is currently available regarding emissions of biogenic volatile organic compounds (BVOCs) in southern Asia. To address the need for BVOC emission estimates in regional atmospheric chemistry simulations, 95 common plant species were screened for emissions of BVO...

  8. 31 CFR 538.537 - Transshipment of goods, technology, and services to or from the Republic of South Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., and services to or from the Republic of South Sudan. 538.537 Section 538.537 Money and Finance... Policy § 538.537 Transshipment of goods, technology, and services to or from the Republic of South Sudan... transshipment of goods, technology, and services through Sudan to or from the Republic of South Sudan...

  9. 31 CFR 538.537 - Transshipment of goods, technology, and services to or from the Republic of South Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., and services to or from the Republic of South Sudan. 538.537 Section 538.537 Money and Finance... Policy § 538.537 Transshipment of goods, technology, and services to or from the Republic of South Sudan... transshipment of goods, technology, and services through Sudan to or from the Republic of South Sudan...

  10. 31 CFR 538.537 - Transshipment of goods, technology, and services to or from the Republic of South Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., and services to or from the Republic of South Sudan. 538.537 Section 538.537 Money and Finance... Policy § 538.537 Transshipment of goods, technology, and services to or from the Republic of South Sudan... transshipment of goods, technology, and services through Sudan to or from the Republic of South Sudan...

  11. Physical- and geochemical properties of core samples from the Swedish part of the southern Baltic Sea: Implications for CO2 storage

    NASA Astrophysics Data System (ADS)

    Elhami, Ehsan; Erlström, Mikael; Ask, Maria; Mattsson, Hans

    2016-04-01

    Feasibility studies of CO2 storage in Sweden has been conducted based on the geological and geophysical data from the southern Baltic Sea (e.g. Juhlin et al., 2013). One suitable formation for CO2 storage may exist below southern Gotland, with good aquifer properties for storage and suitable caprock. We present detailed results from a series of measurements conducted on core samples consisting of Cambrian sandstone (potential reservoir rock) and Ordovician limestone (potential caprock). The core samples are provided by Geological Survey of Sweden (SGU) and were collected from 146-586 m depth. The experiments consist of petrophysical properties measurements (density, porosity, permeability, thermal conductivity and P-wave velocity) and chemical analysis. The two rock types reveal contrasting properties, for example density and P-wave velocity is 2.26±0.13 gr/cm3 and 3.14±1.00 km/s, respectively, for the sandstone (reservoir rock) while significantly higher values were obtained for the limestone (caprock), 2.58±0.08 gr/cm3 and 6.09±0.24 km/s respectively. The objective of this study is to evaluate the interrelationships between the obtained petrophysical and geochemical properties from southern Swedish Baltic Sea to better understand the implications of the evaluated properties for CO2 storage in Sweden.

  12. Geochemical Characteristics of Volcanic Rocks from the Southern Okinawa Trough and its Implications for Tectono-magmatic Evolution

    NASA Astrophysics Data System (ADS)

    Shinjo, R.; Hokakubo, S.; Haraguchi, S.; Matsumoto, T.; Woodhead, J.

    2003-12-01

    The Okinawa Trough is a site of ongoing backarc rifting behind the Ryukyu arc-trench system. Recent intensive surveys, including submersible dives, at the southern Okinawa Trough (SOT) have revealed details of bathymetric, geological, and geophysical features. Here, we present the petrological and geochemical characteristics of volcanic rocks collected during these cruises, and discuss its relation to the evolutionary stage of rifting. Based on bathymetirc and magmatic features, SOT can be divided into two (i.e., eastern and western) segments with non-transform offset at ˜ 123.5° E. The eastern segment represents a well-developed rift system with E-W-trending central graben and separated NE-SW-trending volcanic front; these two features merge at ˜ 125° E. In contrast, the western segment is in the incipient rifting stage; rift axis exists close to 100 km contour of the Wadati-Benioff zone. The most notable feature is the presence of 'abnormal' volcanic chain (Cross Backarc Volcanic Trail, CBVT), which trends NE-SW and is obviously oblique to the axial trend. All rocks are subalkaline, but range from basalt to rhyolite; dacite-rhyolite are dominant in the eastern volcanic front and CBVT. Basalts from both segments are low-K tholeiites; they have high abundance of LILEs relative to HFSEs, negative Nb anomalies on MORB-normalized diagrams, and range of 143Nd/144Nd (0.5128-0.5129) and 87Sr/86Sr (0.7034-0.7048). Pb isotope systematics indicate 206Pb/204Pb=18.398-18.582, 207Pb/204Pb=15.594-15.652 and 208Pb/204Pb=38.570-38.912, clearly above the Northern Hemisphere Reference Line. These elemental and isotopic variations are compatible with derivation from Indian Ocean MORB-like mantle with strong overprint of subduction components from the slab. There is clear difference among more felsic rocks between two segments. At similar silica contents, most of felsic rocks from the western segment, including CBVT rhyolites, have higher LILE contents, 87Sr/86Sr and 208Pb/204Pb

  13. Reworked planktonic Foraminifera from the Late Rupelian of the southern Upper Rhine Graben and their palaeogeographic and biostratigraphic implications

    NASA Astrophysics Data System (ADS)

    Pirkenseer, C.; Spezzaferri, S.; Berger, J.-P.

    2009-04-01

    margin of the Upper Rhine Graben. Reworked Mesozoic and Paleogene calcareous nannoplankton from the Upper Rhine Graben and the Mainz Basin confirms the data derived from planktonic Foraminifera. The existence of reworked planktonic Foraminifera influences the biostratigraphic interpretation of the assemblage ranges attributed to "Série grise" samples. Facultatively reworked planktonic Foraminifera as Subbotina utilisindex and Pseudohastigerina micra ranging from the Lutetian to the Late Rupelian should not be included in the biostratigraphic analyses, as the occurrences of these facultatively reworked species are always linked to those of exclusively Cretaceous and Eocene age. Therefore the age of the "Série grise" deposits at Allschwil-2 is most likely to be placed within the "Chiloguembelina cubensis - Globigerinella obesa / Globorotaloides variabilis"-assemblage range of Mid P20 to Final P21a, lasting considerably longer than the very short Mid P20 range based on the presence of Pseudohastigerina micra as "last occurrence"-marker (PIRKENSEER 2007). This study was funded by the Swiss National Science Foundation projects 109457 and 118025. References: BERGER, J.-P., REICHENBACHER, B., BECKER, D., et al. (2005): Eocene-Pliocene time scale and stratigraphy of the Upper Rhine Graben (URG) and the Swiss Molasse Basin (SMB). - International Journal of Earth Sciences, 94, 4: 711-731. FISCHER, H. (1965): Geologie des Gebietes zwischen Blauen und Pfirter Jura. - Beiträge zur geologischen Karte der Schweiz, NF 122: 106p. PIRKENSEER, C. (2007): Foraminifera, Ostracoda and other microfossils of the Southern Upper Rhine Graben - Palaeoecology, biostratigraphy, palaeogeography and geodynamic implications. - PhD thesis: 340p, Fribourg. ROUSSÉ, S. (2006): Architecture et dynamique des séries marines et continentales de ĺOligocène Moyen et Supérieur du Sud du Fossé Rhénan: Evolution des milieux de dépôt en contexte de rift en marge de ĺavant-pays alpin. - PhD: 471p

  14. The influence of extreme winds on coastal oceanography and its implications for coral population connectivity in the southern Arabian Gulf.

    PubMed

    Cavalcante, Geórgenes H; Feary, David A; Burt, John A

    2016-04-30

    Using long-term oceanographic surveys and a 3-D hydrodynamic model we show that localized peak winds (known as shamals) cause fluctuation in water current speed and direction, and substantial oscillations in sea-bottom salinity and temperature in the southern Persian/Arabian Gulf. Results also demonstrate that short-term shamal winds have substantial impacts on oceanographic processes along the southern Persian/Arabian Gulf coastline, resulting in formation of large-scale (52 km diameter) eddies extending from the coast of the United Arab Emirates (UAE) to areas near the off-shore islands of Iran. Such eddies likely play an important role in transporting larvae from well-developed reefs of the off-shore islands to the degraded reef systems of the southern Persian/Arabian Gulf, potentially maintaining genetic and ecological connectivity of these geographically distant populations and enabling enhanced recovery of degraded coral communities in the UAE. PMID:26506023

  15. Southern Peru desert shattered by the great 2001 earthquake: Implications for paleoseismic and paleo-El Nino-Southern Oscillation records

    USGS Publications Warehouse

    Keefer, David K.; Moseley, Michael E.

    2004-01-01

    In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2-8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term "shattered landscape" to describe the severity of these effects. Long-term consequences of this landscape shattering are inferred to include increased runoff and sediment transport during postearthquake rainstorms. This inference was confirmed during the first minor postearthquake rainstorm there, which occurred in June and July of 2002. Greater amounts of rainfall in this desert region have historically been associated with El Nin??o events. Previous studies of an unusual paleoflood deposit in this region have concluded that it is the product of El Nin??o-generated precipitation falling on seismically disturbed landscapes. The effects of the 2001 earthquake and 2002 rainstorm support that conclusion.

  16. Southern Peru desert shattered by the great 2001 earthquake: Implications for paleoseismic and paleo-El Niño–Southern Oscillation records

    PubMed Central

    Keefer, David K.; Moseley, Michael E.

    2004-01-01

    In the desert region around the coastal city of Ilo, the great southern Peru earthquake of June 23, 2001 (8.2–8.4 moment magnitude), produced intense and widespread ground-failure effects. These effects included abundant landslides, pervasive ground cracking, microfracturing of surficial hillslope materials, collapse of drainage banks over long stretches, widening of hillside rills, and lengthening of first-order tributary channels. We have coined the term “shattered landscape” to describe the severity of these effects. Long-term consequences of this landscape shattering are inferred to include increased runoff and sediment transport during postearthquake rainstorms. This inference was confirmed during the first minor postearthquake rainstorm there, which occurred in June and July of 2002. Greater amounts of rainfall in this desert region have historically been associated with El Niño events. Previous studies of an unusual paleoflood deposit in this region have concluded that it is the product of El Niño-generated precipitation falling on seismically disturbed landscapes. The effects of the 2001 earthquake and 2002 rainstorm support that conclusion. PMID:15263069

  17. Demographic intermediation between development and population redistribution in Sudan.

    PubMed

    Farah, A A

    1983-12-01

    This article analyzes the causes of population distribution in various geographical regions of Sudan. Population distribution is a function of fertility, mortality, and net migration. These variables are primarily caused by changes in socioeconomic factors prevailing in each area. The analysis shows that the population distribution among the geographical regions is primarily shaped by the differential development actions during the last 2 decades. The regional variability of population growth and density largely reflects regional development. Provinces are classified into 3 groups according to stages of population growth. The 1st group is composed of the 3 southern provinces, characterized by the highest mortality, lowest fertility, a marginal volume of net migration, and the lowest overall population growth rate during the last 2 decades. These are the poorest provinces in terms of per capita income, education, communication, and health measures. The 2nd group comprises Dafur, Kordofan, Northern and Red Sea Provinces, which generally reflect an intermediate stage in the demographic evolution in the country. Fertility is positively correlated and mortality is inversely related to the level of per capita income, resulting in an inverse relationship between the 2 vital rates. Therefore, the natural growth will probably increase. However, there are also areas of out-migration. Their future population growth and density will depend on the extent to which the out-migration will affect their natural growth rates. The 3rd group is composed of Khartoum, Blue Nile and Kassala provinces. They have the highest fertility, lowest mortality and highest volume of in-migration. Therefore, they witnessed the highest population growth rate and population density during the period. They encompass the largest urban centers with the highest degree of modernization and family planning activities. It is postulated that their future fertility and mortality rates will decline in varying

  18. Late Holocene Marsh Expansion in Southern San Francisco Bay, California: Implications for the Use of Historic Baselines as Restoration Targets

    EPA Science Inventory

    Currently, the largest tidal wetlands restoration project on the US Pacific Coast is being planned and implemented in southern San Francisco Bay; however, knowledge of baseline conditions of salt marsh extent in the region prior to European settlement is limited. Here, analysis o...

  19. New chronology for the southern Kalahari Group sediments with implications for sediment-cycle dynamics and early hominin occupation

    NASA Astrophysics Data System (ADS)

    Matmon, Ari; Hidy, Alan J.; Vainer, Shlomy; Crouvi, Onn; Fink, David; Erel, Yigal; Arnold, M.; Aumaître, G.; Bourlès, D.; Keddadouche, K.; Horwitz, Liora K.; Chazan, Michael

    2015-07-01

    Kalahari Group sediments accumulated in the Kalahari basin, which started forming during the breakup of Gondwana in the early Cretaceous. These sediments cover an extensive part of southern Africa and form a low-relief landscape. Current models assume that the Kalahari Group accumulated throughout the entire Cenozoic. However, chronology has been restricted to early-middle Cenozoic biostratigraphic correlations and to OSL dating of only the past ~ 300 ka. We present a new chronological framework that reveals a dynamic nature of sedimentation in the southern Kalahari. Cosmogenic burial ages obtained from a 55 m section of Kalahari Group sediments from the Mamatwan Mine, southern Kalahari, indicate that the majority of deposition at this location occurred rapidly at 1-1.2 Ma. This Pleistocene sequence overlies the Archaean basement, forming a significant hiatus that permits the possibility of many Phanerozoic cycles of deposition and erosion no longer preserved in the sedimentary record. Our data also establish the existence of a shallow early-middle Pleistocene water body that persisted for > 450 ka prior to this rapid period of deposition. Evidence from neighboring archeological excavations in southern Africa suggests an association of high-density hominin occupation with this water body.

  20. New chronology for the southern Kalahari Group sediments - implications for sediment-cycle dynamics and basin development

    NASA Astrophysics Data System (ADS)

    Matmon, Ari; Hidy, Alan; Vainer, Shlomy; Crouvi, Onn; Fink, David; Erel, Yigal; Aster Team; Horwitz, Liora; Chazan, Michael

    2016-04-01

    Kalahari Group sediments accumulated in the Kalahari basin, which started forming during the breakup of Gondwana in the early Cretaceous. These sediments cover an extensive part of southern Africa and form a low-relief landscape. Current models assume that the Kalahari Group accumulated throughout the entire Cenozoic. However, chronology has been restricted to early-middle Cenozoic biostratigraphic correlations and to OSL dating of only the past ~300 ka. We present a new chronological framework that reveals a dynamic nature of sedimentation in the southern Kalahari. Cosmogenic burial ages obtained from a 55 m section of Kalahari Group sediments from the Mamatwan Mine, southern Kalahari, indicate that the majority of deposition at this location occurred rapidly at 1-1.2 Ma. This Pleistocene sequence overlies the Archaean basement, forming a significant hiatus that permits the possibility of many Phanerozoic cycles of deposition and erosion no longer preserved in the sedimentary record. Our data also establish the existence of a shallow early-middle Pleistocene water body that persisted for >450 ka prior to this rapid period of deposition and suggesting an Okavango-like environment. Evidence from neighboring archaeological excavations in southern Africa suggests an association of high-density hominin occupation with this water body.

  1. Characteristics and implication of clay minerals in the northern and southern parts of the Chelung-pu fault, Taiwan

    NASA Astrophysics Data System (ADS)

    Hashimoto, Y.; Ujiie, K.; Sakaguchi, A.; Tanaka, H.

    2007-10-01

    In this study, we report the characteristics of clay minerals present in the Chelung-pu fault in Taiwan. In the 1999 Chi-Chi earthquake, different slip motions were recorded along the Chelung-pu fault in the northern and southern parts of the fault. The characteristics of clay minerals present in the fault zones can be attributed to the differences in motion. We analyzed the shallow drill core samples obtained from the northern and southern sites penetrating the fault. The clay minerals identified in most of the samples from both the sites are smectite, illite, and chlorite. There are illite-smectite mixed layers with a high illite content and no chlorite-smectite mixed layer. In some samples, no smectite is detected. We also examined the iron content and symmetry of iron and magnesium in the silicate and hydroxide layers in chlorite. At the northern site, the total iron content in chlorite of gouge is larger than that of the host rocks. On the other hand, at the southern site, the total iron content varies widely. It is hypothesized that the smectite consumption and differences in the characteristics of chlorite may be controlled by the differences in the lithology, fluid chemistry, fluid temperature, or fault activities (heating or breakage) between the northern and southern sites.

  2. Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China

    PubMed Central

    Zhang, Jien; Wang, Tianming; Ge, Jianping

    2015-01-01

    In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p < 0.05). The spring EVI had largest increase in space. The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI. The increase in EVI was not driven by annual average temperature and annual precipitation. By referencing ecological restoration statistical data and field observations, we showed that ecological restoration programs significantly improved vegetation cover in southern China. Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China’s afforestation program. PMID:26115116

  3. Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China.

    PubMed

    Zhang, Jien; Wang, Tianming; Ge, Jianping

    2015-01-01

    In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p < 0.05). The spring EVI had largest increase in space. The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI. The increase in EVI was not driven by annual average temperature and annual precipitation. By referencing ecological restoration statistical data and field observations, we showed that ecological restoration programs significantly improved vegetation cover in southern China. Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China's afforestation program. PMID:26115116

  4. Base- and precious-metal deposits in the Basin and Range of Southern California and Southern Nevada - Metallogenic implications of lead isotope studies

    USGS Publications Warehouse

    Church, S.E.; Cox, D.P.; Wooden, J.L.; Tingley, J.V.; Vaughn, R.B.

    2005-01-01

    Southern California and southern Nevada contain abundant lead-zinc deposits with strikingly different characteristics. On the west, the Darwin Terrane contains abundant Jurassic and Cretaceous intrusions surrounded by lead-zinc skarn and replacement deposits rich in pyrite and manganese minerals. The Tecopa Terrane is east of the Darwin Terrane and contains some lead deposits that are hosted by the Proterozoic Noonday Dolomite. These lead deposits have no consistent relation to igneous rocks; they contain mainly galena, and are devoid of pyrite and manganese minerals. Other skarn and vein deposits in the Ivanpah and Tecopa districts are more closely associated with igneous rocks. Mississippi Valley type lead-zinc deposits are present still farther to the east in the Goodsprings Terrane in Nevada. These deposits are hosted by breccias formed below the Mississippian-Pennsylvanian unconformity and are unrelated to igneous rocks. Deposits in the Darwin Terrane have lead isotopic signatures that lie along a mantle-sediment mixing line indicating that they formed in a continental arc setting analogous to that for the plutons in the Sierra Nevada batholith [Chen, J.H. and Tilton, G.R., 1991. Application of lead and strontium isotopic relationships to the petrogenesis of granitoid rocks, central Sierra Nevada batholith, California. Geological Society of America Bulletin 103, 439-447]. Encroachment of this continental arc on the North American continent in the eastern part of the Darwin Terrane resulted in a lead isotopic signature that is like that of the strongly contaminated plutons [Chen, J.H. and Tilton, G.R., 1991. Application of lead and strontium isotopic relationships to the petrogenesis of granitoid rocks, central Sierra Nevada batholith, California. Geological Society of America Bulletin 103, 439-447]. Many deposits from the Inyo Mountains on east side of the Owens Valley have lead isotopic signatures that reflect this encroachment. To the east in the Tecopa

  5. Mycetoma in the Sudan: An Update from the Mycetoma Research Centre, University of Khartoum, Sudan

    PubMed Central

    Fahal, Ahmed; Mahgoub, EL Sheikh; Hassan, Ahmed M. EL; Abdel-Rahman, Manar Elsheikh

    2015-01-01

    This communication reports on the Mycetoma Research Centre of the University of Khartoum, Sudan experience on 6,792 patients seen during the period 1991–2014.The patients were predominately young (64% under 30 years old) males (76%). The majority (68%) were from the Sudan mycetoma belt and 28% were students. Madurella mycetomatis eumycetoma was the most common type (70%). In 66% of the patients the duration of the disease was less than five years, and 81% gave a history of sinuses discharging mostly black grains (78%). History of trauma at the mycetoma site was reported in 20%. Local pain was reported in 27% of the patients, and only 12% had a family history of mycetoma. The study showed that 57% of the patients had previous surgical excisions and recurrence, and only 4% received previous medical treatment for mycetoma. Other concomitant medical diseases were reported in 4% of the patients. The foot (76%) and hand (8%) were the most commonly affected sites. Less frequently affected sites were the leg and knee (7%), thigh (2%), buttock (2%) and arm and forearm (1%). Rare sites included the chest wall, head and neck, back, abdominal wall, perineum, oral cavity, tongue and eye. Multiple sites mycetoma was recorded in 135 (2%) of cases. At presentation, 37% of patients had massive lesions, 79% had sinuses, 8% had local hyper-hydrosis at the mycetoma lesion, 11% had regional lymphadenopathy, while 6% had dilated tortuous veins proximal to the mycetoma lesions. The diagnosis of mycetoma was established by combined imaging techniques and cytological, histopathological, serological tests and grain culture. Patients with actinomycetoma received a combination of antimicrobial agents, while eumycetoma patients received antifungal agents combined with various surgical excisions. Surgical excisions in the form of wide local excision, debridement or amputation were done in 807 patients, and of them 248 patients (30.7%) had postoperative recurrence. Different types of

  6. Mycetoma in the Sudan: an update from the Mycetoma Research Centre, University of Khartoum, Sudan.

    PubMed

    Fahal, Ahmed; Mahgoub, El Sheikh; El Hassan, Ahmed M; Abdel-Rahman, Manar Elsheikh

    2015-03-01

    This communication reports on the Mycetoma Research Centre of the University of Khartoum, Sudan experience on 6,792 patients seen during the period 1991-2014.The patients were predominately young (64% under 30 years old) males (76%). The majority (68%) were from the Sudan mycetoma belt and 28% were students. Madurella mycetomatis eumycetoma was the most common type (70%). In 66% of the patients the duration of the disease was less than five years, and 81% gave a history of sinuses discharging mostly black grains (78%). History of trauma at the mycetoma site was reported in 20%. Local pain was reported in 27% of the patients, and only 12% had a family history of mycetoma. The study showed that 57% of the patients had previous surgical excisions and recurrence, and only 4% received previous medical treatment for mycetoma. Other concomitant medical diseases were reported in 4% of the patients. The foot (76%) and hand (8%) were the most commonly affected sites. Less frequently affected sites were the leg and knee (7%), thigh (2%), buttock (2%) and arm and forearm (1%). Rare sites included the chest wall, head and neck, back, abdominal wall, perineum, oral cavity, tongue and eye. Multiple sites mycetoma was recorded in 135 (2%) of cases. At presentation, 37% of patients had massive lesions, 79% had sinuses, 8% had local hyper-hydrosis at the mycetoma lesion, 11% had regional lymphadenopathy, while 6% had dilated tortuous veins proximal to the mycetoma lesions. The diagnosis of mycetoma was established by combined imaging techniques and cytological, histopathological, serological tests and grain culture. Patients with actinomycetoma received a combination of antimicrobial agents, while eumycetoma patients received antifungal agents combined with various surgical excisions. Surgical excisions in the form of wide local excision, debridement or amputation were done in 807 patients, and of them 248 patients (30.7%) had postoperative recurrence. Different types of amputations

  7. New sources of grain mold resistance among accessions from Sudan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fifty-nine sorghum accessions from Sudan were evaluated in replicated plots at Isabela, Puerto Rico, for resistance against Fusarium thapsinum, one of the causal agents of grain mold. The environmental conditions during this study, especially at and after physiological maturity were optimal for gra...

  8. Child Prodigy in Astronomy: A Biographical Study from the Sudan

    ERIC Educational Resources Information Center

    Khaleefa, Omar

    2009-01-01

    Although many studies have been conducted in the West regarding child prodigies, no such studies have taken place in indigenous Arab cultures--particularly not in Sudan. The present study attempts to bridge the existing gap in this area by focusing on a Sudanese child prodigy with extraordinary inclination towards astronomy. It is a qualitative…

  9. Tertiary age for upper Nubian sandstone formation, central Sudan

    SciTech Connect

    Prasad, G.; Lejal-Nicol, A.; Vaudois-Mieja, N.

    1986-02-01

    In central and northern Sudan, oil exploration is now active in the basins containing sediments of the Nubian Sandstone Formation. On the evidence of planned pipeline construction, significant volumes of oil appear to have been discovered in southwestern Sudan. A newly discovered flora from the upper Nubian Sandstone Formation near Khartoum in central Sudan is Tertiary in age. The flora is well preserved, and comprises leaves, flowers, and fruits, many not yet described. At the generic level, they are comparable to forms that are known fro the Eocene to Miocene. Aquatic plants indicate a lacustrine paleoenvironment; humid tropical forests thrived on the lakeshores. The Nubian Sandstone Formation of Sudan had been considered to be entirely of Cretaceous age; this new flora shifts the upper boundary into the Tertiary. The Tertiary Hudi Chert, found in scattered outcrops in the region of Atbara, was considered to overlie the Nubian Sandstone Formation. The authors suggest that the Hudi Chert is partly age equivalent to the Tertiary upper Nubian Sandstone at Jebel Mudaha.

  10. Sudanese Images of the Other: Education and Conflict in Sudan

    ERIC Educational Resources Information Center

    Breidlid, Anders

    2010-01-01

    Education can contribute to peace and reconciliation as well as to conflict and strife. The complex, often contradictory role of education in conflict is explored in this article in relation to Sudan. The focus of the article is the North-South conflict, bearing in mind that other, "minor" wars and military clashes in both the North and South have…

  11. The Role of Education in Sudan's Civil War

    ERIC Educational Resources Information Center

    Breidlid, Anders

    2013-01-01

    This article addresses the role that education plays in conflict, with specific reference to the civil war in Sudan. It analyses the ideological basis of the Sudanese government (GoS) during the civil war, with special reference to the role of religion and ethnicity. It shows how the primary education system was based on the Islamist ideology of…

  12. Unsafe abortion and abortion care in Khartoum, Sudan.

    PubMed

    Kinaro, Joyce; Ali, Tag Elsir Mohamed; Schlangen, Rhonda; Mack, Jessica

    2009-11-01

    Unsafe abortion in Sudan results in significant morbidity and mortality. This study of treatment for complications of unsafe abortion in five hospitals in Khartoum, Sudan, included a review of hospital records and a survey of 726 patients seeking abortion-related care from 27 October 2007 to 31 January 2008, an interview of a provider of post-abortion care and focus group discussions with community leaders. Findings demonstrate enormous unmet need for safe abortion services. Abortion is legally restricted in Sudan to circumstances where the woman's life is at risk or in cases of rape. Post-abortion care is not easily accessible. In a country struggling with poverty, internal displacement, rural dwelling, and a dearth of trained doctors, mid-level providers are not allowed to provide post-abortion care or prescribe contraception. The vast majority of the 726 abortion patients in the five hospitals were treated with dilatation and curettage (D&C), and only 12.3% were discharged with a contraceptive method. Some women waited long hours before treatment was provided; 14.5% of them had to wait for 5-8 hours and 7.3% for 9-12 hours. Mid-level providers should be trained in safe abortion care and post-abortion care to make these services accessible to a wider community in Sudan. Guidelines should be developed on quality of care and should mandate the use of manual vacuum aspiration or misoprostol for medical abortion instead of D&C. PMID:19962640

  13. Late Pleistocene evolution of Scott Glacier, southern Transantarctic Mountains: implications for the Antarctic contribution to deglacial sea level

    NASA Astrophysics Data System (ADS)

    Bromley, Gordon R. M.; Hall, Brenda L.; Stone, John O.; Conway, Howard

    2012-09-01

    Glacial deposits preserved adjacent to Scott Glacier, southern Transantarctic Mountains, provide a record of past fluctuations in the thickness of the West Antarctic Ice Sheet. Geologic mapping of these deposits, in conjunction with emerging 10Be surface-exposure data, indicate that the most recent expansion of Scott Glacier occurred during the last glacial maximum in response to grounding of ice in the Ross Sea Embayment. At that time, the ice surface at the confluence of Scott Glacier and the West Antarctic Ice Sheet lay at ˜1100 m elevation. While this ice-surface reconstruction is in accord with other geologic estimates from throughout the Ross Sea Embayment, it contrasts with most computer-based simulations, which tend to overestimate former ice thickness in the southern Ross Sea. Together with recently modelled estimates of Antarctica's contribution to sea level, this finding calls into question an Antarctic source for meltwater pulse 1A.

  14. Growth responses of Ulva prolifera to inorganic and organic nutrients: Implications for macroalgal blooms in the southern Yellow Sea, China.

    PubMed

    Li, Hongmei; Zhang, Yongyu; Han, Xiurong; Shi, Xiaoyong; Rivkin, Richard B; Legendre, Louis

    2016-01-01

    The marine macrophyte Ulva prolifera is the dominant green-tide-forming seaweed in the southern Yellow Sea, China. Here we assessed, in the laboratory, the growth rate and nutrient uptake responses of U. prolifera to different nutrient treatments. The growth rates were enhanced in incubations with added organic and inorganic nitrogen [i.e. nitrate (NO3(-)), ammonium (NH4(+)), urea and glycine] and phosphorus [i.e. phosphate (PO4(3-)), adenosine triphosphate (ATP) and glucose 6-phosphate (G-6-P)], relative to the control. The relative growth rates of U. prolifera were higher when enriched with dissolved organic nitrogen (urea and glycine) and phosphorus (ATP and G-6-P) than inorganic nitrogen (NO3(-) and NH4(+)) and phosphorus (PO4(3-)). In contrast, the affinity was higher for inorganic than organic nutrients. Field data in the southern Yellow Sea showed significant inverse correlations between macroalgal biomass and dissolved organic nutrients. Our laboratory and field results indicated that organic nutrients such as urea, glycine and ATP, may contribute to the development of macroalgal blooms in the southern Yellow Sea. PMID:27199215

  15. Recent developments in understanding the tectonic evolution of the Southern California offshore area: Implications for earthquake-hazard analysis

    USGS Publications Warehouse

    Fisher, M.A.; Langenheim, V.E.; Nicholson, C.; Ryan, H.F.; Sliter, R.W.

    2009-01-01

    During late Mesozoic and Cenozoic time, three main tectonic episodes affected the Southern California offshore area. Each episode imposed its unique structural imprint such that early-formed structures controlled or at least influenced the location and development of later ones. This cascaded structural inheritance greatly complicates analysis of the extent, orientation, and activity of modern faults. These fault attributes play key roles in estimates of earthquake magnitude and recurrence interval. Hence, understanding the earthquake hazard posed by offshore and coastal faults requires an understanding of the history of structural inheritance and modifi-cation. In this report we review recent (mainly since 1987) findings about the tectonic development of the Southern California offshore area and use analog models of fault deformation as guides to comprehend the bewildering variety of offshore structures that developed over time. This report also provides a background in regional tectonics for other chapters in this section that deal with the threat from offshore geologic hazards in Southern California. ?? 2009 The Geological Society of America.

  16. Growth responses of Ulva prolifera to inorganic and organic nutrients: Implications for macroalgal blooms in the southern Yellow Sea, China

    PubMed Central

    Li, Hongmei; Zhang, Yongyu; Han, Xiurong; Shi, Xiaoyong; Rivkin, Richard B.; Legendre, Louis

    2016-01-01

    The marine macrophyte Ulva prolifera is the dominant green-tide-forming seaweed in the southern Yellow Sea, China. Here we assessed, in the laboratory, the growth rate and nutrient uptake responses of U. prolifera to different nutrient treatments. The growth rates were enhanced in incubations with added organic and inorganic nitrogen [i.e. nitrate (NO3−), ammonium (NH4+), urea and glycine] and phosphorus [i.e. phosphate (PO43−), adenosine triphosphate (ATP) and glucose 6-phosphate (G-6-P)], relative to the control. The relative growth rates of U. prolifera were higher when enriched with dissolved organic nitrogen (urea and glycine) and phosphorus (ATP and G-6-P) than inorganic nitrogen (NO3− and NH4+) and phosphorus (PO43−). In contrast, the affinity was higher for inorganic than organic nutrients. Field data in the southern Yellow Sea showed significant inverse correlations between macroalgal biomass and dissolved organic nutrients. Our laboratory and field results indicated that organic nutrients such as urea, glycine and ATP, may contribute to the development of macroalgal blooms in the southern Yellow Sea. PMID:27199215

  17. Growth responses of Ulva prolifera to inorganic and organic nutrients: Implications for macroalgal blooms in the southern Yellow Sea, China

    NASA Astrophysics Data System (ADS)

    Li, Hongmei; Zhang, Yongyu; Han, Xiurong; Shi, Xiaoyong; Rivkin, Richard B.; Legendre, Louis

    2016-05-01

    The marine macrophyte Ulva prolifera is the dominant green-tide-forming seaweed in the southern Yellow Sea, China. Here we assessed, in the laboratory, the growth rate and nutrient uptake responses of U. prolifera to different nutrient treatments. The growth rates were enhanced in incubations with added organic and inorganic nitrogen [i.e. nitrate (NO3‑), ammonium (NH4+), urea and glycine] and phosphorus [i.e. phosphate (PO43‑), adenosine triphosphate (ATP) and glucose 6-phosphate (G-6-P)], relative to the control. The relative growth rates of U. prolifera were higher when enriched with dissolved organic nitrogen (urea and glycine) and phosphorus (ATP and G-6-P) than inorganic nitrogen (NO3‑ and NH4+) and phosphorus (PO43‑). In contrast, the affinity was higher for inorganic than organic nutrients. Field data in the southern Yellow Sea showed significant inverse correlations between macroalgal biomass and dissolved organic nutrients. Our laboratory and field results indicated that organic nutrients such as urea, glycine and ATP, may contribute to the development of macroalgal blooms in the southern Yellow Sea.

  18. Paleomagnetism, rock magnetism and opaque mineralogy of iron ore deposits from southern Mexico and their implications for quantitative modelling of magnetometric data

    SciTech Connect

    Alva-Valdivia, L.M.; Fucugauchi, Urrutia, J.; Bohnel, H.; Moran Zenteno, D.J. )

    1990-06-01

    Paleomagnetism, Rock Magnetism and Opaque Mineralogy of Iron Ore Deposits from Southern Mexico and Their Implications for Quantitative Modelling of Magnetometric Data. The tectonic history of the Pacific continental margin is critical for understanding their mineral deposits. The margin presents intrusive and volcanic activity characteristic of magmatic arcs of subduction zones, which are genetically related with deposits of Cu, Fe, Mo, Au, and Ag. Although the tectonic history has been complex, involving oblique plate subduction, lateral movements, accretion of magmatic arcs and oceanic plateaux, and lateral displacements of major blocks, the mineral deposits are spatially distributed along elongated belts that roughly follow the margin. The authors have conducted paleomagnetic, rock magnetic, and petrological studies of the iron ore deposits to investigate genesis, magnetic mineralogy, stratigraphic relationships, metamorphism, and applications on quantitative modelling of magnetometric data. The remanent magnetization and susceptibility data are necessary for interpretation of magnetic anomalies. The results permit a comparison of the mineral deposits along the continental margin.

  19. Sea-Level Rise Implications for Coastal Protection from Southern Mediterranean to the U.S.A. Atlantic Coast

    NASA Astrophysics Data System (ADS)

    Ismail, Nabil; Williams, Jeffress

    2013-04-01

    planning and restoration projects will require a major undertaking by national governments and international institutions. Joint research projects between international organizations such as: USA research centers ( USGS, NOAA, Corps of Engineers), EU sponsored project groups, EU coastal marine centers as well as other world wide coastal research institutes (CoRI, Alexandria) are encouraged to advance the state of the art on managing coasts to adapt to sea level rise employing cost-effective coastal protection technologies. References 1.Williams, S.J.,"Sea-Level Rise Implications for Coastal Regions", Journal of Coastal Research, Vol. 63, 2013. 2.Ismail, N.,Wiegel, R., "Sustainable Solutions for Coastal Zone Management of Lowland and River Delta Coastlines", Proc. International Conference- Littoral 2012, Ostende, Belgium, November 27-29, 2012. 3.Ismail, N., Iskander, M., and El-Sayed, W. "Assessment of Coastal Flooding at Southern Mediterranean with Global Outlook for Lowland Coastal Zones", Proc. International Conference on Coastal Engineering, ASCE, July 1-6, 2012, Santander, Spain. 4.Moser, S. C., Williams,J.S., and Boesch, D. F., " Wicked Challenges at Land's End: Managing Coastal Vulnerability Under Climate Change'', Annual. Review of Environmental Resources, 37:51-78, 2012.

  20. The upper lithostratigraphic unit of ANDRILL AND-2A core (Southern McMurdo Sound, Antarctica): Local Pleistocene volcanic sources, paleoenvironmental implications and subsidence in the southern Victoria Land Basin

    NASA Astrophysics Data System (ADS)

    Del Carlo, P.; Panter, K. S.; Bassett, K.; Bracciali, L.; Di Vincenzo, G.; Rocchi, S.

    2009-11-01

    We report results from the study of the uppermost 37 m of the Southern McMurdo Sound (SMS) AND-2A drill core, corresponding to the lithostratigraphic unit 1 (LSU 1), the most volcanogenic unit within the core. We present data on the age, composition, volcanological and depositional features of the volcanic sedimentary and tephra deposits of LSU 1 and discuss their source, mechanisms of emplacement and environment of deposition. Sedimentary features and compositional data indicate shallow water sedimentation for the whole of LSU 1. Most of LSU 1 deposits are a mixture of near primary volcanic material with minor exotic clasts derived from the Paleozoic crystalline basement rocks. Among volcanic materials, glassy particles are the most abundant. They were produced by mildly explosive basaltic eruptions occurring in subaerial and subaqueous environments. The Dailey Islands group, 13 km south-southwest of the SMS drill-site, has been identified as a possible source for the volcanics on the basis of similarity in composition and age. 40Ar- 39Ar laser step-heating analyses on a lava sample from Juergens Island yields an age of 775 ± 22 ka. Yet because of the minimal reworking features of vitriclasts, preservation of fragile structures in volcaniclastic sediments and evidence for volcanic seamounts to the north of the Dailey Islands, it is likely that some of the material originated also from vents close to the drill-site. Evidence for local volcanic sources and for deposition of sediments in a shallow marine environment provides indications about the local paleogeography and implications for the subsidence history of the southern Victoria Land Basin from Pleistocene to Recent.

  1. The discovery of new deep-sea hydrothermal vent communities in the southern ocean and implications for biogeography.

    PubMed

    Rogers, Alex D; Tyler, Paul A; Connelly, Douglas P; Copley, Jon T; James, Rachael; Larter, Robert D; Linse, Katrin; Mills, Rachel A; Garabato, Alfredo Naveira; Pancost, Richard D; Pearce, David A; Polunin, Nicholas V C; German, Christopher R; Shank, Timothy; Boersch-Supan, Philipp H; Alker, Belinda J; Aquilina, Alfred; Bennett, Sarah A; Clarke, Andrew; Dinley, Robert J J; Graham, Alastair G C; Green, Darryl R H; Hawkes, Jeffrey A; Hepburn, Laura; Hilario, Ana; Huvenne, Veerle A I; Marsh, Leigh; Ramirez-Llodra, Eva; Reid, William D K; Roterman, Christopher N; Sweeting, Christopher J; Thatje, Sven; Zwirglmaier, Katrin

    2012-01-01

    Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than

  2. Paleomagnetic results from the Cambrian and Ordovician sediments of Bornholm (Denmark) and Southern Sweden and paleogeographical implications for Baltica

    NASA Astrophysics Data System (ADS)

    Lewandowski, Marek; Abrahamsen, Niels

    2003-11-01

    If apparent polar wander paths (APWP) cross, the question arises how to prove the older magnetization to be primary and not just a younger overprint. This problem is typically met in areas affected by percolating mineralizing fluids and/or heating due to a younger regional igneous activity. The Permian magnetic overprint is the classical example. Earlier paleomagnetic studies over the Lowermost Cambrian Nekso Sandstone Fm (NSF) of Bornholm (Denmark) yielded a characteristic remanent magnetization (ChRM) similar to the Permian directions for Baltica. Since a possible reason could be a chemical overprint, we checked whether this phenomenon did take place on a regional scale. Some samples therefore were collected from other Lower Cambrian clastics of Bornholm and Southern Scandinavia. In result we show that the well-grouped and stable ChRM of the NSF contrasts with fairly chaotic, soft, and badly preserved magnetizations of the Balka, Hardeberga, Mickwitzia, and Lingulid sandstones of Bornholm and Southern Sweden, thus not indicating widespread paleomagnetic overprint. We demonstrate that the ChRM of the NSF is most probably of syndepositional/early diagenetic origin and its similarity to the Permian direction for Baltica is only casual. We propose a normal polarity and a near-equatorial position on the Southern Hemisphere for Baltica in the early Cambrian time, as well as a more complicated trend of the APWP for this paleocontinent than envisaged by other authors. Paleomagnetic results from the Arenigian limestones of the Laesaa Formation (Bornholm) that yield excellently defined but most probably only secondary components are also presented.

  3. The Discovery of New Deep-Sea Hydrothermal Vent Communities in the Southern Ocean and Implications for Biogeography

    PubMed Central

    Rogers, Alex D.; Tyler, Paul A.; Connelly, Douglas P.; Copley, Jon T.; James, Rachael; Larter, Robert D.; Linse, Katrin; Mills, Rachel A.; Garabato, Alfredo Naveira; Pancost, Richard D.; Pearce, David A.; Polunin, Nicholas V. C.; German, Christopher R.; Shank, Timothy; Boersch-Supan, Philipp H.; Alker, Belinda J.; Aquilina, Alfred; Bennett, Sarah A.; Clarke, Andrew; Dinley, Robert J. J.; Graham, Alastair G. C.; Green, Darryl R. H.; Hawkes, Jeffrey A.; Hepburn, Laura; Hilario, Ana; Huvenne, Veerle A. I.; Marsh, Leigh; Ramirez-Llodra, Eva; Reid, William D. K.; Roterman, Christopher N.; Sweeting, Christopher J.; Thatje, Sven; Zwirglmaier, Katrin

    2012-01-01

    Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than

  4. Interseismic Strain Accumulation in the Imperial Valley and Implications for Triggering of Large Earthquakes in Southern California

    NASA Astrophysics Data System (ADS)

    Crowell, B. W.; Bock, Y.; Sandwell, D. T.

    2009-12-01

    From February, 2008 to March, 2009, we performed three rapid-static Global Positioning System (GPS) surveys of 115 geodetic monuments stretching from the United States-Mexico border into the Coachella Valley using the method of instantaneous positioning. The monuments are located in key areas near the Imperial, Superstition Hills, San Jacinto, San Andreas and Brawley Faults with nominal baselines generally less than 10 km. We perform a bicubic spline interpolation on the crustal motion vectors from the campaign measurements and 1005 continuous GPS monuments in western North America and solve for the velocity gradient tensor to look at the maximum shear strain, dilatation and rotation rates in the Imperial Valley. We then compare our computed strain field to that computed using the Southern California Earthquake Center Crustal Motion Map 3.0, which extends through 2003 and includes 840 measurements. We show that there is an interseismic strain transient that corresponds to an increase in the maximum shear strain rate of 0.7 μstrain/yr near Obsidian Buttes since 2003 along a fault referred to as the Obsidian Buttes Fault (OBF). A strong subsidence signal of 27 mm/yr and a left-lateral increase of 10 mm/yr are centered along the OBF. Changes in the dilatation and rotation rates confirm the increase in left-lateral motion, as well as infer a strong increase in spreading rate in the southern Salton Sea. The increase in spreading rate has caused an accelerated slip rate along the southern San Andreas near Durmid Hill as evidenced by continuous GPS, which has the potential for earthquake triggering.

  5. Paleomagnetism of an east-west transect across the Cascade arc in southern Washington: Implications for regional tectonism

    USGS Publications Warehouse

    Hagstrum, J.T.; Swanson, D.A.; Evarts, R.C.

    1999-01-01

    Paleomagnetic data from a transect across the Cascade arc in southern Washington were collected to test models of vertical axis rotations for this part of the Pacific Northwest and to provide information on the tectonic history of the St. Helens seismic zone. The 75 site-mean directions are divided into three groups based on isotopic, fission track, and stratigraphic ages. Group 1 consists of samples from rocks deposited between 39 and 30 Ma and shows a mean clockwise vertical axis rotation of 34?? ?? 13??, group 2 consists of samples from rocks deposited be-tween 30 and 24 Ma and shows a mean clockwise rotation of 17?? ?? 11??, and group 3 consists of samples from rocks between 24 and 16 Ma and shows a mean clockwise rotation of 20?? ?? 12??. Although these three values of rotation are statistically indistinguishable at the 95% confidence level, we interpret them in combination with other data to indicate differential rotation across the St. Helens seismic zone (SHZ). The available paleomagnetic data for Eocene-Oligocene rocks west of the seismic zone show clockwise vertical axis rotations of 30?? ?? 8?? and 35?? ?? 9?? consistent with the value for group 1. The rotational values for groups 2 and 3 and the intrusive suite of Kidd Creek (13 Ma), despite their different ages, have similar values east of the SHZ. Comparing these groups of data east and west of the seismic zone indicates a differential rotation of 10?? ?? 3?? across it. In addition, the rates of rotation in southern Washington are similar to those for rocks in the western Cascades of Oregon and indicate that rotational deformation of Miocene age extends northward into southern Washington and eastward into the axis of the arc.

  6. Polar and low polar solvents media effect on dipole moments of some diazo Sudan dyes

    NASA Astrophysics Data System (ADS)

    Zakerhamidi, M. S.; Golghasemi Sorkhabi, Sh.; Shamkhali, A. N.

    2014-06-01

    Absorption and fluorescence spectra of three Sudan dyes (SudanIII, SudanIV and Sudan black B) were recorded in various solvents with different polarity in the range of 300-800 nm, at room temperature. The solvatochromic method was used to investigate dipole moments of these dyes in ground and excited states, in different media. The solvatochromic behavior of these substances and their solvent-solute interactions were analyzed via solvent polarity parameters. Obtained results express the effects of solvation on tautomerism and molecular configuration (geometry) of Sudan dyes in solvent media with different polarity. Furthermore, analyze of solvent-solute interactions and value of ground and excited states dipole moments suggests different forms of resonance structures for Sudan dyes in polar and low-polar solvents.

  7. Os, Sr, Nd, and Pb isotope systematics of southern African peridotite xenoliths - Implications for the chemical evolution of subcontinental mantle

    NASA Technical Reports Server (NTRS)

    Walker, R. J.; Carlson, R. W.; Shirey, S. B.; Boyd, F. R.

    1989-01-01

    Isotope analyses of Os, Sr, Nd, and Pb elements were caried out on twelve peridotite xenoliths from the Jagersfontein, Letseng-la-terae, Thaba Patsoa, Mothae, and Premier kimberlites of southern Africa, to investigate the timing and the nature of melt extraction from the continental lithosphere and its relation to the continent formation and stabilization. The distinct Os and Pb isotopic characteristics found in these samples suggested that both the low- and the high-temperature peridotites reside in an ancient stable lithospheric 'keel' to the craton that has been isolated from chemical exchange with the sublithospheric mantle for time periods in excess of 2 Ga.

  8. Middle Miocene paleoaltimetry of southern Tibet: Implications for the role of mantle thickening and delamination in the Himalayan orogen

    NASA Astrophysics Data System (ADS)

    Currie, Brian S.; Rowley, David B.; Tabor, Neil J.

    2005-03-01

    The stable isotope composition of pedogenic and early diagenetic carbonates from the Oiyug Basin of southern Tibet allows model estimates of the paleoaltimetry of the Tibetan Plateau for the middle Miocene. Pedogenic calcium carbonate nodules have average δ18Occ values of -19.6‰, whereas nodular lacustrine dolomites range in composition from -7.6‰ to -5.5‰. The most negative of the carbonate isotope values can be used to constrain the oxygen isotope composition of paleoprecipitation, from which model estimates of paleoaltimetry can be made. Model results indicate that the southern Tibetan Plateau achieved elevations of ˜5200 +1370/-605 m by at least 15 Ma. Our results are identical within uncertainty to previous workers' paleoelevation estimates based on Oiyug Basin fossil floral physiognomy. This is the first time that two paleoaltimeters have been directly compared and are in accord. Collectively, these data strongly support tectonic models in which thickening of mantle lithosphere beneath the domain of crustal thickening and subsequent detachment of the mantle lithosphere plays an indiscernible role in the elevation history of this part of the Himalaya-Tibet orogenic system.

  9. Magnetostratigraphy of syntectonic growth strata and implications for the late Cenozoic deformation in the Baicheng Depression, Southern Tian Shan

    NASA Astrophysics Data System (ADS)

    Zhang, Zhiliang; Sun, Jimin; Tian, Zhonghua; Gong, Zhijun

    2016-03-01

    The collision between India and Eurasia in the Cenozoic has caused a series of intracontinental deformation in the foreland basins of Tian Shan, but there are debates about the timing of tectonic deformation and the relationship between tectonic uplift and sediment accumulation in the foreland basins. Based on the magnetostratigraphy of growth strata in the Baicheng Depression, Southern Tian Shan, we suggest that an episode of crustal shortening in the late Cenozoic evidenced by syntectonic growth strata in the Kelasu-Yiqikelike structural belt (KYSB) initiated at ∼5.3 Ma, since then the sedimentation rate accelerated abruptly and coarse molasse deposits accumulated. Combined with the results of growth strata on both flanks of Tian Shan and the fact that the Xiyu Formation on the southern limb of the Kasangtuokai Anticline was involved into the growth strata, we conclude that the period from ∼7-5 Ma to the early Pleistocene was one of the important episodes of intracontinental deformation in the foreland basins of Tian Shan, as a response to the Cenozoic collision between India and Eurasia.

  10. Thrust faults of southern Diamond Mountains, central Nevada: Implications for hydrocarbons in Diamond Valley and at Yucca Mountain

    SciTech Connect

    French, D.E.

    1993-04-01

    Overmature Mississippian hydrocarbon source rocks in the southern Diamond Mountains have been interpreted to be a klippe overlying less mature source rocks and represented as an analogy to similar conditions near Yucca Mountain (Chamberlain, 1991). Geologic evidence indicates an alternative interpretation. Paleogeologic mapping indicates the presence of a thrust fault, referred to here as the Moritz Nager Thrust Fault, with Devonian rocks emplaced over Permian to Mississippian strata folded into an upright to overturned syncline, and that the overmature rocks of the Diamond Mountains are in the footwall of this thrust. The upper plate has been eroded from most of the Diamond Mountains but remnants are present at the head of Moritz Nager Canyon and at Sentinel Mountain. Devonian rocks of the upper plate comprised the earliest landslide megabreccia. Later, megabreccias of Pennsylvanian and Permian rocks of the overturned syncline of the lower plate were deposited. By this interpretation the maturity of lower-plate source rocks in the southern Diamond Mountains, which have been increased by tectonic burial, is not indicative of conditions in Diamond Valley, adjacent to the west, where upper-plate source rocks might be present in generating conditions. The interpretation that overmature source rocks of the Diamond Mountains are in a lower plate rather than in a klippe means that this area is an inappropriate model for the Eleana Range near Yucca Mountain.

  11. Hydroclimate implications of thermocline variability in the southern South China Sea over the past 180,000 yr

    NASA Astrophysics Data System (ADS)

    Dong, Liang; Li, Li; Li, Qianyu; Wang, Hui; Zhang, Chuanlun L.

    2015-03-01

    Based on core-top calibration, the TEX 86H-derived temperature has been considered as representing subsurface sea temperature (SSST), and the difference between the U37K‧-derived sea-surface temperature (SST) and the TEX 86H-derived SSST can be used to reflect the depth of thermocline (DOT) in the South China Sea region (Jia et al., 2012). We evaluated the DOT dynamics in late Quaternary records using this approach on paired analysis of samples from core MD05-2896/7 in the southern South China Sea. The reconstructed DOT over the last 180,000 yr (180 ka) displays a shoaling trend in glacial periods, which may be attributed to the strengthened cyclonic gyre by the enhanced East Asian winter monsoon and Walker circulation with prominent La Niña-like state, and vice versa in interglacial periods corresponding to reduced winter monsoon with enhanced El Niño-like state. These upper-water thermal variations testify that enhanced winter monsoon was the direct cause of an uplifted local thermocline during glacial or La Niña-like states with strengthened cyclonic gyre due to positive wind stress curl in the southern South China Sea. Our results provide insights into the relationship between monsoon and ENSO on both glacial and millennial time scales.

  12. Implications of Nubian-Like Core Reduction Systems in Southern Africa for the Identification of Early Modern Human Dispersals

    PubMed Central

    Phillips, Natasha

    2015-01-01

    Lithic technologies have been used to trace dispersals of early human populations within and beyond Africa. Convergence in lithic systems has the potential to confound such interpretations, implying connections between unrelated groups. Due to their reductive nature, stone artefacts are unusually prone to this chance appearance of similar forms in unrelated populations. Here we present data from the South African Middle Stone Age sites Uitpanskraal 7 and Mertenhof suggesting that Nubian core reduction systems associated with Late Pleistocene populations in North Africa and potentially with early human migrations out of Africa in MIS 5 also occur in southern Africa during early MIS 3 and with no clear connection to the North African occurrence. The timing and spatial distribution of their appearance in southern and northern Africa implies technological convergence, rather than diffusion or dispersal. While lithic technologies can be a critical guide to human population flux, their utility in tracing early human dispersals at large spatial and temporal scales with stone artefact types remains questionable. PMID:26125972

  13. Late Pleistocene and Holocene uplift history of Cyprus: implications for active tectonics along the southern margin of the Anatolian microplate

    USGS Publications Warehouse

    Harrison, R.W.; Tsiolakis, E.; Stone, B.D.; Lord, A.; McGeehin, J.P.; Mahan, S.A.; Chirico, P.

    2013-01-01

    The nature of the southern margin of the Anatolian microplate during the Neogene is complex, controversial and fundamental in understanding active plate-margin tectonics and natural hazards in the Eastern Mediterranean region. Our investigation provides new insights into the Late Pleistocene uplift history of Cyprus and the Troodos Ophiolite. We provide isotopic (14C) and radiogenic (luminescence) dates of outcropping marine sediments in eastern Cyprus that identify periods of deposition during marine isotope stages (MIS) 3, 4, 5 and 6. Past sea-levels indicated by these deposits are c. 95±25 m higher in elevation than estimates of worldwide eustatic sea-level. An uplift rate of c. 1.8 mm/year and possibly as much as c. 4.1 mm/year in the past c. 26–40 ka is indicated. Holocene marine deposits also occur at elevations higher than those expected for past SL and suggest uplift rates of c. 1.2–2.1 mm/year. MIS-3 marine deposits that crop out in southern and western Cyprus indicate uniform island-wide uplift. We propose a model of tectonic wedging at a plate-bounding restraining bend as a mechanism for Late Pleistocene to Holocene uplift of Cyprus; uplift is accommodated by deformation and seismicity along the margins of the Troodos Ophiolite and re-activation of its low-angle, basal shear zone.

  14. Vertical stratification of fatty acids in the blubber of southern elephant seals (Mirounga leonina): implications for diet analysis.

    PubMed

    Best, Narelle J; Bradshaw, Corey J A; Hindell, Mark A; Nichols, Peter D

    2003-02-01

    Fatty acid signature analysis (FASA) is a powerful ecological tool that uses essential fatty acids (FA) from the tissues of animals to indicate aspects of diet. However, the presence of vertical stratification in FA distribution throughout blubber complicates the application of FASA to marine mammals. Blubber biopsy samples were collected from adult female southern elephant seals (Mirounga leonina) from Macquarie Island (n=11), and blubber cores were divided into inner and outer sections to determine the degree to which the blubber layer was stratified in FA composition, we found 19 FA from both blubber layers in greater than trace amounts (>0.5%). The inner and outer blubber layers could be separated using principal components analysis based on the relative proportion of FA in each layer. Dietary polyunsaturated fatty acids (PUFA) were also observed in significantly higher proportions in the inner blubber layer. Due to the degree of FA stratification in southern elephant seals, we concur with other marine mammal studies that sampling only the outer blubber layer will result in a loss of recently accumulated information regarding diet structure (as indicated by 'surplus' PUFA from the diet). This finding suggests that differential mobilization/deposition of certain FA may result in a modified signature from prey to predator. Thus, sampling animals to recover the inner blubber layer is important for studies attempting to describe aspects of marine mammal diet. This can be achieved in animals such as pinnipeds where the whole blubber layer can be readily sampled. PMID:12568803

  15. Provenance and tectonic implications of heavy minerals in Pliocene-Pleistocene siliciclastic sediments of the southern Apennines, Italy

    NASA Astrophysics Data System (ADS)

    Acquafredda, P.; Fornelli, A.; Piccarreta, G.; Summa, V.

    1997-10-01

    During the late Tortonian-Pleistocene, rifting in the Tyrrhenian region and compression in the Apennines coexisted, with an eastward migration of the rift basin-thrust belt-foredeep systems. In a northwest-southeast area of the southern Apennine Pliocene deposits, accumulated in piggy-back basins, and Pliocene-Pleistocene sediments deposited in the foredeep basins, are contiguous. Here our attention is focused on the heavy minerals, which are sensitive indicators of source rocks. Garnet, blue amphibole, staurolite, clinopyroxene, epidote have been analysed and compared with the minerals of the likely protoliths. Blue amphibole and staurolite derive from Early Miocene 'Tufiti di Tusa e Arenarie di Corleto' Formation; pyroxenes derive from Pleistocene Vulture volcanics and, possibly from Pliocene volcaniclastic strata cropping out in Basilicata. Interestingly, blue amphibole and staurolite, present in the Early Miocene volcanolithic and quartzofeldspathic sandstones of the 'Tufiti di Tusa e Arenarie di Corleto' Formation, are absent in Tortonian siliciclastic strata, but appear again in Pliocene-Pleistocene siliciclastic sediments. The space-time distribution of these minerals was controlled by important morphostructural modifications affecting the southern Apennine thrust belt.

  16. [The SERS Detection of Sudan I by Using AAO as Template to Prepare the Substrate].

    PubMed

    Pan, Xiao-hui; Zhang, Qin; Guo, Wei; Chen, Fa-he

    2015-06-01

    The large-scale controllable, ordered two-dimensional arrays of gold nanostructure with hot-spot were prepared together with chemical molecules were modified on the surface to concentrate Sudan I within the zone of the SERS effect, which lead to analytical detection of Sudan I in high resolution. The vapor of gold was deposed on anodic aluminum oxide(AAO) template by -200 nm thickness to replicate its nanochannels, and the negative structure i. e. large-scale ordered gold nano-hemisphere array, was obtained after the removal of the template of AAO by NaOH solution. Au nano-hemisphere array was modified by 1-Dodecanethiol which can be self-assembled monolayer on the surface and concentrate Sudan I within the zone of the SERS detection, which can facilitate the measurement of Sudan I. Due to the order and regularity of Au nano-hemisphere array, the signal of Sudan I in the range of laser illumination is stable and uniform, and the quantitative analysis of Sudan I was realized. The SERS intensity of Sudan I is logistic proportional to the concentration in the range of 10(-7) to 5 x 10(-4) mol x L(-1). The corresponding correlation coefficient of the liner equation is 0.99, the recoveries of Sudan I are between 77% - 117%. The limit of detection for Sudan I is 4 x 10(-1) mol x L(-1), comparable to that of HPLC of Chinese national standard method. PMID:26601366

  17. Occurrence of Sudan I in paprika fruits caused by agricultural environmental contamination.

    PubMed

    Lian, Yunhe; Gao, Wei; Zhou, Li; Wu, Naiying; Lu, Qingguo; Han, Wenjie; Tie, Xiaowei

    2014-05-01

    Current research has demonstrated the presence of sub parts per billion levels of Sudan dye in paprika fruits during the vegetation process, which is difficult to understand on the basis of the conventional concept of cross-contamination or malicious addition. Detailed surveys on Sudan dyes I-IV in paprika fruits, soils, and agronomic materials used from seven fields of Xinjiang (China) were conducted to investigate the natural contamination. Results revealed that Sudan dyes II-IV were never detected and that Sudan I existed in almost all samples except for the mulching film and irrigation water. The higher total amount of Sudan I in soils, pesticides, and fertilizers compared to coated seeds indicated the combination of Sudan I-contaminated soils and application of Sudan I-containing agronomic materials constitutes a major source of 0.18-2.52 μg/kg levels of Sudan I in fruits during the growth period. The study offers a more reasonable explanation for the previously observed Sudan I in paprika fruits. PMID:24766082

  18. Evidence for and implications of sedimentary diapirism and mud volcanism in the southern Utopia highland lowland boundary plain, Mars

    NASA Astrophysics Data System (ADS)

    Skinner, James A.; Tanaka, Kenneth L.

    2007-01-01

    Several types of spatially associated landforms in the southern Utopia Planitia highland-lowland boundary (HLB) plain appear to have resulted from localized geologic activity, including (1) fractured rises, (2) elliptical mounds, (3) pitted cones with emanating lobate materials, and (4) isolated and coalesced cavi (depressions). Stratigraphic analysis indicates these features are Hesperian or younger and may be associated with resurfacing that preferentially destroyed smaller ( <8 km diameter) impact craters. Based on landform geomorphologies and spatial distributions, the documented features do not appear to be specifically related to igneous or periglacial processes or the back-wasting and erosion of the HLB scarp. We propose that these features are genetically related to and formed by sedimentary (mud) diapirs that ascended from zones of regionally confined, poorly consolidated, and mechanically weak material. We note morphologic similarities between the mounds and pitted cones of the southern Utopia boundary plain and terrestrial mud volcanoes in the Absheron Peninsula, Azerbaijan. These analogs provide a context for understanding the geological environments and processes that supported mud diapir-related modification of the HLB. In southern Utopia, mud diapirs near the Elysium volcanic edifice may have resulted in laccolith-like intrusions that produced the fractured rises, while in the central boundary plain mud diapirs could have extruded to form pitted cones, mounds, and lobate flows, perhaps related to compressional stresses that account for wrinkle ridges. The removal of material a few kilometers deep by diapiric processes may have resulted in subsidence and deformation of surface materials to form widespread cavi. Collectively, these inferences suggest that sedimentary diapirism and mud volcanism as well as related surface deformations could have been the dominant Hesperian mechanisms that altered the regional boundary plain. We discuss a model in which

  19. Crustal velocity model along the southern Cuban margin: implications for the tectonic regime at an active plate boundary

    NASA Astrophysics Data System (ADS)

    Moreno, Bladimir; Grandison, Margaret; Atakan, Kuvvet

    2002-11-01

    A new 1-D velocity model along the southern Cuban margin has been determined using local earthquake data, which are the result of the merged Cuban and Jamaican catalogues. Simultaneous inversion using joint-hypocentre determination was applied to solve the coupled hypocentre-velocity model problem. We obtained a seven-layer model with an average Moho interface at 20 km. The average velocity was found to be 7.6 km s-1 on the top of the crust-mantle transition zone and 6.9 km s-1 in the basaltic layer of the crust. The improvement in the earthquake locations allowed us for the first time to use local seismicity to characterize the activity on local faults and the stress regime in the area. For this purpose, 34 earthquake focal mechanisms were determined along the eastern segments of the Oriente Fault. These solutions are consistent with the known left-lateral strike-slip motion along this major structure as well as with the stress regime of two local structures: (1) the Cabo Cruz Basin and (2) the Santiago deformed belt. The first structure is dominated by normal faults with minor strike-slip components and the second by reverse faults. The shallow seismicity in the Cabo Cruz Basin is associated with fault planes trending N55°-58°E and dipping 38°-45° to the north. The Santiago deformed belt, on the other hand, exhibits diverse fault plane orientations. These local structures account for most of the earthquake activity along the southern Cuban margin. Deep seismicity observed in the Santiago deformed belt, supported by focal mechanisms, suggests underthrusting of the Gonave Microplate beneath the Cuban Block in this area. The principal stress orientations obtained from stress inversion of earthquake focal mechanisms suggest a thrust faulting regime along the Southern Cuban margin. We obtained a nearly horizontal σ1 and nearly vertical σ3, which indicates active compressional deformation along the major Oriente transcurrent fault in agreement with the dominant

  20. Evidence for and implications of sedimentary diapirism and mud volcanism in the southern Utopia highland-lowland boundary plain, Mars

    USGS Publications Warehouse

    Skinner, J.A., Jr.; Tanaka, K.L.

    2007-01-01

    Several types of spatially associated landforms in the southern Utopia Planitia highland-lowland boundary (HLB) plain appear to have resulted from localized geologic activity, including (1) fractured rises, (2) elliptical mounds, (3) pitted cones with emanating lobate materials, and (4) isolated and coalesced cavi (depressions). Stratigraphic analysis indicates these features are Hesperian or younger and may be associated with resurfacing that preferentially destroyed smaller (< 8 ?? km diameter) impact craters. Based on landform geomorphologies and spatial distributions, the documented features do not appear to be specifically related to igneous or periglacial processes or the back-wasting and erosion of the HLB scarp. We propose that these features are genetically related to and formed by sedimentary (mud) diapirs that ascended from zones of regionally confined, poorly consolidated, and mechanically weak material. We note morphologic similarities between the mounds and pitted cones of the southern Utopia boundary plain and terrestrial mud volcanoes in the Absheron Peninsula, Azerbaijan. These analogs provide a context for understanding the geological environments and processes that supported mud diapir-related modification of the HLB. In southern Utopia, mud diapirs near the Elysium volcanic edifice may have resulted in laccolith-like intrusions that produced the fractured rises, while in the central boundary plain mud diapirs could have extruded to form pitted cones, mounds, and lobate flows, perhaps related to compressional stresses that account for wrinkle ridges. The removal of material a few kilometers deep by diapiric processes may have resulted in subsidence and deformation of surface materials to form widespread cavi. Collectively, these inferences suggest that sedimentary diapirism and mud volcanism as well as related surface deformations could have been the dominant Hesperian mechanisms that altered the regional boundary plain. We discuss a model in

  1. Kinematics and age of Early Tertiary trench parallel volcano-tectonic lineaments in southern Mexico: Tectonic implications

    NASA Astrophysics Data System (ADS)

    Martini, M.; Ferrari, L.; Lopez Martinez, M.; Cerca Martinez, M.; Serrano Duran, L.

    2007-05-01

    We present new geological, structural, and geochronological data that constrain the timing and geometry of Early Tertiary strike slip deformation in southwestern Mexico and its relation with the concurrent magmatic activity. Geologic mapping in Guerrero and Michoacan States documented two regional WNW trending volcano-tectonic lineaments sub parallel to the present trench. The southernmost lineament runs for ~140 km from San Miguel Totolapan area (NW Guerrero) to Sanchiqueo (SE Michoacan), and passes through Ciudad Altamirano. Its southeastern part is marked by the alignment of at least eleven silicic to intermediate major domes as well as by the course of the Balsas River. The northwestern part of the lineament is characterized by ductile left lateral shear zones in Early Tertiary plutonic rocks observed in the Rio Chiquito valley. Domes near Ciudad Altamirano are unaffected by ductile shearing and yielded a ~42 Ma 40Ar/39Ar age, setting a minimum age for this deformation. The northern volcano-tectonic lineament runs for ~190 km between the areas of Huitzuco in northern Guerrero and the southern part of the Tzitzio fold in eastern Michoacan. The Huautla, Tilzapotla, Taxco, La Goleta and Nanchititla silicic centers (all in the range 37-34 Ma) are emplaced along this lineament, which continues to the WNW trough a mafic dike swarm exposed north of Tiquicheo (37-35 Ma) and the Purungueo subvolcanic body (~42 Ma). These rocks, unaffected by ductile shearing, give a minimum age of deformation similar to the southern Totolapan-Sanquicheo lineament. Post ~42 Ma deformation is essentially brittle and is characterized by several left lateral and right lateral transcurrent faults with typical Riedel patterns. Other trench-parallel left lateral shear zones active in pre-Oligocene times were recently reported in western Oaxaca. The recognizing of Early Tertiary trench-parallel and left-lateral ductile shearing in internal areas of southern Mexico suggest a field of widely

  2. Glacial geomorphology of the Torres del Paine region (southern Patagonia): Implications for glaciation, deglaciation and paleolake history

    NASA Astrophysics Data System (ADS)

    García, Juan-Luis; Hall, Brenda L.; Kaplan, Michael R.; Vega, Rodrigo M.; Strelin, Jorge A.

    2014-01-01

    The processes affecting paleoclimate variability and Pleistocene glacial landscape development in the southern mid-latitudes remain poorly understood, in part because of the scarcity of comprehensive, well-studied records. Glacial landforms are invaluable for reconstructing past ice-sheet, climate, and associated environmental changes along the southern Andes, but there are significant spatial and temporal gaps in existing data. In this paper, we present new geomorphic and sedimentologic analyses, including surficial maps, for the Torres del Paine region (51°S, 73°W), southern South America. Our findings provide a new framework for understanding changes in the regional glacier history and Pleistocene landscape development. Glacial extent during the local last glacial maximum (LGM) remains unknown but new chronological data supported by geomorphic evidence afford evidence for a larger ice sheet at Torres del Paine than previously assumed. Deglaciation from the local LGM was underway by 17,400 ± 200 (1σ) cal. yr. BP. As opposed to previous suggestions, we have found that most of the moraines fringing the lakes in the Torres del Paine national park were deposited during a late-glacial expansion that occurred between 14,100 and 12,500 cal. yr. BP. Late-glacial advances also have been documented recently for the Última Esperanza and Lago Argentino basins to the south and north of Torres del Paine, respectively, suggesting an overall regional ice response to a climate signal. The Tehuelche paleolake accompanied each of the ice-sheet fluctuations in Torres del Paine. New data document at least three main phases of this paleolake, which drained eastward to the Atlantic Ocean, while the Andes gaps were blocked with ice. During the late phase of glacial lake formation, when water levels reached 125-155 m a.s.l., the lake likely merged with paleolake Consuelo in the Última Esperanza area at the end of the last glaciation. Lake Tehuelche in Torres del Paine had drained

  3. Logistics of Guinea Worm Disease Eradication in South Sudan

    PubMed Central

    Jones, Alexander H.; Becknell, Steven; Withers, P. Craig; Ruiz-Tiben, Ernesto; Hopkins, Donald R.; Stobbelaar, David; Makoy, Samuel Yibi

    2014-01-01

    From 2006 to 2012, the South Sudan Guinea Worm Eradication Program reduced new Guinea worm disease (dracunculiasis) cases by over 90%, despite substantial programmatic challenges. Program logistics have played a key role in program achievements to date. The program uses disease surveillance and program performance data and integrated technical–logistical staffing to maintain flexible and effective logistical support for active community-based surveillance and intervention delivery in thousands of remote communities. Lessons learned from logistical design and management can resonate across similar complex surveillance and public health intervention delivery programs, such as mass drug administration for the control of neglected tropical diseases and other disease eradication programs. Logistical challenges in various public health scenarios and the pivotal contribution of logistics to Guinea worm case reductions in South Sudan underscore the need for additional inquiry into the role of logistics in public health programming in low-income countries. PMID:24445199

  4. The Status of Women in Physics in Sudan

    NASA Astrophysics Data System (ADS)

    Abdelbagi, Abdrazig M.; Sirelkhatim, Amna H.; Abdelrahman, Wafaa S.; Osman, Mai E.; Shatir, Tahani S.

    2009-04-01

    The progress of women in physics education in the last five years was surveyed in the six top universities in Sudan. The data reveal great increases in the number of females studying undergraduate physics. Most were studying experimental physics rather than theoretical physics, especially the laser and electronics fields. It appears undergraduate laboratory experiments are an important factor in attracting women to physics. Our survey found that girls are encouraged to study physics at the high school level. However, the data also showed that the fewer tendencies to study physics among the women after high school are due to the limited job opportunities and low income of teachers. Postgraduate physics study is handicapped by lack of institutions, financial constraints, and lack of qualified advisors. Improvement of education systems and new ways of teaching will have great influences on attracting women to physics in Sudan.

  5. Paleomagnetism of the Cambrian Sediments in Bornholm (Denmark) and Southern Sweden and Implications for Paleogeography of Baltica

    NASA Astrophysics Data System (ADS)

    Lewandowski, M.; Abrahamsen, N.

    2001-12-01

    In Bornholm the Phanerozoic sedimentary succession overlying Precambrian basement starts with the Lower Cambrian (ca. 545 Ma) Nekso Sandstone Fm (NSF) that, in the earlier paleomagnetic analyses, have yielded characteristic magnetization (ChRM) similar to the Permian direction for Baltica. Here, we present paleomagnetic results from other Lower Cambrian formations in Bornholm (Balka Sandstone, Broens Odde siltstone) and in southern Sweden (Hardebega, Mickwitzia and Lingula Sandstones). Lithologically, most of these formations are very similar to the NSF and they are all considered stratigraphically younger. The intention was to check, whether a Permian paleomagnetic overprint occured on a regional scale and could it be attributed to secondary magnetic phases originating from fluids, which possibly traveled laterally along the contact between the basement and the Lower Cambrian sediments. In this report we show results of this regional test, followed by a comprehensive re-analysis of our Nekso data, including new results obtained after supplementary sampling and new petrologic information, which appeared recently. We have found that the NSF possessed a unique ChRM. The well-grouped and stable characteristic magnetization of the Nekso Sandstone contrasts with fairly chaotic, soft and badly preserved magnetization of the Balka, the Hardeberga, the Mickwitzia and the Lingulid sandstones of Bornholm and southern Sweden. A regional geological context, including the inferred diagenetic evolution of Lower Cambrian sediments, points to a syndepositional/early diagenetic origin of the characteristic remanence of the Nekso Sandstone, revealing a stable remanence applicable for plate tectonic interpretations. Similarity of the characteristic remanence of the NSF to the Permian direction for Baltica has been confirmed, but it is supposed to be casual, because of lack of any sign of a regional Permian remagnetization within the other Cambrian deposits of Southern Scandinavia

  6. Analysis of energy-saving potential in residential buildings in Xiamen City and its policy implications for southern China

    NASA Astrophysics Data System (ADS)

    Guo, Fei

    The buildings sector is the largest energy-consuming sector in the world. Residential buildings consume about three-quarters of the final energy in the buildings sector. Promoting residential energy savings is in consequence critical for addressing many energy-use-related environmental challenges, such as climate change and air pollution. Given China's robust economic growth and fast urbanization, it is now a critical time to develop policy interventions on residential energy use in the nation. With this as a background, this dissertation explores effective policy intervention opportunities in southern China through analyzing the residential energy-saving potential, using the city of Xiamen as a case study. Four types of residential energy-saving potential are analyzed: technical potential, economic potential, maximum achievable potential (MAP), and possible achievable potential (PAP). Of these, the first two types are characterized as static theoretical evaluation, while the last two represent dynamic evaluation within a certain time horizon. The achievable potential analyses are rarely seen in existing literature. The analytical results reveal that there exists a significant technical potential for residential energy savings of about 20.9-24.9% in the city of Xiamen. Of the technical potential, about two-thirds to four-fifths are cost-effective from the government or society perspective. The cost-effectiveness is evaluated by comparing the "Levelized Cost of Conserved Energy (LCOCE)" of available advanced technical measures with the "Actual Cost" of conserved energy. The "Actual Cost" of energy is defined by adding the environmental externalities costs and hidden government subsidies over the retail prices of energy. The achievable potential analyses are particularly based on two key realistic factors: 1) the gradual ramping-up adoption process of advanced technical measures; and 2) individuals' adoption-decision making on them. For implementing the achievable

  7. Transpressional segment boundaries in strike-slip fault systems offshore southern California: Implications for fluid expulsion and cold seep habitats

    NASA Astrophysics Data System (ADS)

    Maloney, Jillian M.; Grupe, Benjamin M.; Pasulka, Alexis L.; Dawson, Katherine S.; Case, David H.; Frieder, Christina A.; Levin, Lisa A.; Driscoll, Neal W.

    2015-05-01

    The importance of tectonics and fluid flow in controlling cold seep habitats has long been appreciated at convergent margins but remains poorly understood in strike-slip systems. Here we present geophysical, geochemical, and biological data from an active methane seep offshore from Del Mar, California, in the inner California borderlands (ICB). The location of this seep appears controlled by localized transpression associated with a step in the San Diego Trough fault zone and provides an opportunity to examine the interplay between fluid expulsion and restraining step overs along strike-slip fault systems. These segment boundaries may have important controls on seep locations in the ICB and other margins characterized by strike-slip faulting (e.g., Greece, Sea of Marmara, and Caribbean). The strike-slip fault systems offshore southern California appear to have a limited distribution of seep sites compared to a wider distribution at convergent plate boundaries, which may influence seep habitat diversity and connectivity.

  8. Origin of REE-rich ferrocarbonatites in southern Siberia (Russia): implications based on melt and fluid inclusions

    NASA Astrophysics Data System (ADS)

    Prokopyev, Ilya R.; Borisenko, Alexander S.; Borovikov, Andrey A.; Pavlova, Galina G.

    2016-06-01

    Fe-rich carbonatites with a mineral assemblage of ankerite-calcite or siderite are widespread in southern Siberia, Russia. The siderite carbonatites are associated with F-Ba-Sr-REE mineralization and have a 40Ar/39Ar age of 117.2 ± 1.3 Ma. Melt and fluid inclusions suggest that the carbonatites formed from volatile-rich alkali- and chloride-bearing carbonate melts. Ankerite-calcite carbonatites formed from carbonatite melt at a temperature of more than 790 °C. The ferrocarbonatites (the second phase of carbonatite intrusion) formed from a sulfate-carbonate-chloride fluid phase (brine-melt) at >650 °C and ≥360 MPa. The brine-melt fluid phase had high concentrations of Fe and LREEs. A subsequent hydrothermal overprint contributed to the formation of economically important barite-Sr-fluorite-REE mineralization in polymict siderite breccia.

  9. Reproductive biology and implications for management of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf.

    PubMed

    Grandcourt, E M; Al Abdessalaam, T Z; Francis, F; Al Shamsi, A T

    2010-12-01

    The reproductive biology of the spangled emperor Lethrinus nebulosus in the southern Arabian Gulf was determined from the examination of 781 individuals collected between September 2008 and August 2009. There was no histological evidence of adult sex change, and sex ratios did not differ significantly from unity across all size and age classes. Testes had an ovarian structure and a remnant lumen which was not used for sperm transport; furthermore, residual oocytes were observed in the testes of some immature, resting and developing males. A dramatic change in the sex ratio of the smallest and youngest size and age classes suggested that juvenile female to male sex change occurred between 21·0 cm fork length (L(F)) and 24·0 cm L(F) at 1 year of age. The combination of histological evidence with the sexual composition of the size and age structures suggests a non-functional protogynous hermaphroditic sexual pattern, which is analogous to functional gonochorism. The spawning season was well defined, occurring once a year during March, April and early May. Peaks in spawning occurred after full moons, there was a cessation in spawning activity after new moons and spawning was completed within three lunar cycles. The distribution of males over the entire size and age ranges and the absence of inactive mature females during the spawning season suggested that the population was not constrained by sperm limitation. Size-specific and age-specific reproductive potential indicated that conventional regulations that equate the mean size at first capture to sexual maturation are unsuitable for the management of L. nebulosus. The maximum recorded age (11 years), small mean size and young age at sexual maturation (L(m50) = 26·7 cm L(F), 2·1 years, for females and 19·4 cm L(F), 0·5 years, for males) may be a direct result of intensive demersal fishing in the southern Arabian Gulf. PMID:21155780

  10. Peleolakes and impact basins in southern Arabia Terra, including Meridiani Planum: Implications for the formation of hematite deposits on Mars

    USGS Publications Warehouse

    Newsom, Horton E.; Barber, C.A.; Hare, T.M.; Schelble, R.T.; Sutherland, V.A.; Feldman, W.C.

    2003-01-01

    The hematite deposit in Meridiani Planum was selected for a Mars Exploration Rover (MER) landing site because water could be involved in the formation of hematite, and water is a key ingredient in the search for life. Our discovery of a chain of paleolake basins and channels along the southern margin of the hematite deposits in Meridiani Planum with the presence of the strongest hematite signature adjacent to a paleolake basin, supports the possible role of water in the formation of the hematite and the deposition of other layered materials in the region. The hematite may have formed by direct precipitation from lake water, as coatings precipitated from groundwater, or by oxidation of preexisting iron oxide minerals. The paleolake basins were fed by an extensive channel system, originating from an area larger than Texas and located south of the Schiaparelli impact basin. On the basis of stratigraphic relationships, the formation of channels in the region occurred over much of Mars' history, from before the layered materials in Meridiani Planum were deposited until recently. The location of the paleolake basins and channels is connected with the impact cratering history of the region. The earliest structure identified in this study is an ancient circular multiringed basin (800-1600 km diameter) that underlies the entire Meridiani Planum region. The MER landing site is located on the buried northern rim of a later 150 km diameter crater. This crater is partially filled with layered deposits that contained a paleolake in its southern portion. Copyright 2003 by the American Geophysical Union.

  11. Determinants of Persistence and Tolerance of Carnivores on Namibian Ranches: Implications for Conservation on Southern African Private Lands

    PubMed Central

    Lindsey, Peter Andrew; Havemann, Carl Peter; Lines, Robin; Palazy, Lucille; Price, Aaron Ernest; Retief, Tarryn Anne; Rhebergen, Tiemen; Van der Waal, Cornelis

    2013-01-01

    Changing land use patterns in southern Africa have potential to dramatically alter the prospects for carnivore conservation. Understanding these influences is essential for conservation planning. We interviewed 250 ranchers in Namibia to assess human tolerance towards and the distribution of large carnivores. Cheetahs (Acinonyx jubatus), leopards (Panthera pardus) and brown hyaenas (Hyaena brunnea) were widely distributed on Namibian farmlands, spotted hyaenas (Crocuta crocuta) had a narrower distribution, and wild dogs (Lycaon pictus) and lions (Panthera leo) are largely limited to areas near source populations. Farmers were most tolerant of leopards and least tolerant of lions, wild dogs and spotted hyaenas. Several factors relating to land use correlated consistently with carnivore-presence and landowner tolerance. Carnivores were more commonly present and/or tolerated where; wildlife diversity and biomass were higher; income from wildlife was higher; income from livestock was lower; livestock biomass was lower; in conservancies; game fencing was absent; and financial losses from livestock depredation were lower. Efforts to create conditions whereby the costs associated with carnivores are lowest, and which confer financial value to them are likely to be the most effective means of promoting carnivore conservation. Such conditions are achieved where land owners pool land to create conservancies where livestock are replaced with wildlife (or where livestock husbandry is improved) and where wildlife generates a significant proportion of ranch income. Additional measures, such as promoting improved livestock husbandry and educational outreach efforts may also help achieve coexistence with carnivores. Our findings provide insights into conditions more conducive to the persistence of and tolerance towards large carnivores might be increased on private (and even communal) lands in Namibia, elsewhere in southern and East Africa and other parts of the world where

  12. Historical land-use and landscape change in southern Sweden and implications for present and future biodiversity.

    PubMed

    Cui, Qiao-Yu; Gaillard, Marie-José; Lemdahl, Geoffrey; Stenberg, Li; Sugita, Shinya; Zernova, Ganna

    2014-09-01

    The two major aims of this study are (1) To test the performance of the Landscape Reconstruction Algorithm (LRA) to quantify past landscape changes using historical maps and related written sources, and (2) to use the LRA and map reconstructions for a better understanding of the origin of landscape diversity and the recent loss of species diversity. Southern Sweden, hemiboreal vegetation zone. The LRA was applied on pollen records from three small bogs for four time windows between AD 1700 and 2010. The LRA estimates of % cover for woodland/forest, grassland, wetland, and cultivated land were compared with those extracted from historical maps within 3-km radius around each bog. Map-extracted land-use categories and pollen-based LRA estimates (in % cover) of the same land-use categories show a reasonable agreement in several cases; when they do not agree, the assumptions used in the data (maps)-model (LRA) comparison are a better explanation of the discrepancies between the two than possible biases of the LRA modeling approach. Both the LRA reconstructions and the historical maps reveal between-site differences in landscape characteristics through time, but they demonstrate comparable, profound transformations of the regional and local landscapes over time and space due to the agrarian reforms in southern Sweden during the 18th and 19th centuries. The LRA was found to be the most reasonable approach so far to reconstruct quantitatively past landscape changes from fossil pollen data. The existing landscape diversity in the region at the beginning of the 18th century had its origin in the long-term regional and local vegetation and land-use history over millennia. Agrarian reforms since the 18th century resulted in a dramatic loss of landscape diversity and evenness in both time and space over the last two centuries leading to a similarly dramatic loss of species (e.g., beetles). PMID:25478148

  13. Historical land-use and landscape change in southern Sweden and implications for present and future biodiversity

    PubMed Central

    Cui, Qiao-Yu; Gaillard, Marie-José; Lemdahl, Geoffrey; Stenberg, Li; Sugita, Shinya; Zernova, Ganna

    2014-01-01

    The two major aims of this study are (1) To test the performance of the Landscape Reconstruction Algorithm (LRA) to quantify past landscape changes using historical maps and related written sources, and (2) to use the LRA and map reconstructions for a better understanding of the origin of landscape diversity and the recent loss of species diversity. Southern Sweden, hemiboreal vegetation zone. The LRA was applied on pollen records from three small bogs for four time windows between AD 1700 and 2010. The LRA estimates of % cover for woodland/forest, grassland, wetland, and cultivated land were compared with those extracted from historical maps within 3-km radius around each bog. Map-extracted land-use categories and pollen-based LRA estimates (in % cover) of the same land-use categories show a reasonable agreement in several cases; when they do not agree, the assumptions used in the data (maps)-model (LRA) comparison are a better explanation of the discrepancies between the two than possible biases of the LRA modeling approach. Both the LRA reconstructions and the historical maps reveal between-site differences in landscape characteristics through time, but they demonstrate comparable, profound transformations of the regional and local landscapes over time and space due to the agrarian reforms in southern Sweden during the 18th and 19th centuries. The LRA was found to be the most reasonable approach so far to reconstruct quantitatively past landscape changes from fossil pollen data. The existing landscape diversity in the region at the beginning of the 18th century had its origin in the long-term regional and local vegetation and land-use history over millennia. Agrarian reforms since the 18th century resulted in a dramatic loss of landscape diversity and evenness in both time and space over the last two centuries leading to a similarly dramatic loss of species (e.g., beetles). PMID:25478148

  14. Determinants of persistence and tolerance of carnivores on Namibian ranches: implications for conservation on Southern African private lands.

    PubMed

    Lindsey, Peter Andrew; Havemann, Carl Peter; Lines, Robin; Palazy, Lucille; Price, Aaron Ernest; Retief, Tarryn Anne; Rhebergen, Tiemen; Van der Waal, Cornelis

    2013-01-01

    Changing land use patterns in southern Africa have potential to dramatically alter the prospects for carnivore conservation. Understanding these influences is essential for conservation planning. We interviewed 250 ranchers in Namibia to assess human tolerance towards and the distribution of large carnivores. Cheetahs (Acinonyx jubatus), leopards (Panthera pardus) and brown hyaenas (Hyaena brunnea) were widely distributed on Namibian farmlands, spotted hyaenas (Crocuta crocuta) had a narrower distribution, and wild dogs (Lycaon pictus) and lions (Panthera leo) are largely limited to areas near source populations. Farmers were most tolerant of leopards and least tolerant of lions, wild dogs and spotted hyaenas. Several factors relating to land use correlated consistently with carnivore-presence and landowner tolerance. Carnivores were more commonly present and/or tolerated where; wildlife diversity and biomass were higher; income from wildlife was higher; income from livestock was lower; livestock biomass was lower; in conservancies; game fencing was absent; and financial losses from livestock depredation were lower. Efforts to create conditions whereby the costs associated with carnivores are lowest, and which confer financial value to them are likely to be the most effective means of promoting carnivore conservation. Such conditions are achieved where land owners pool land to create conservancies where livestock are replaced with wildlife (or where livestock husbandry is improved) and where wildlife generates a significant proportion of ranch income. Additional measures, such as promoting improved livestock husbandry and educational outreach efforts may also help achieve coexistence with carnivores. Our findings provide insights into conditions more conducive to the persistence of and tolerance towards large carnivores might be increased on private (and even communal) lands in Namibia, elsewhere in southern and East Africa and other parts of the world where

  15. Increased dry-season length over southern Amazonia in recent decades and its implication for future climate projection

    PubMed Central

    Fu, Rong; Yin, Lei; Li, Wenhong; Arias, Paola A.; Dickinson, Robert E.; Huang, Lei; Chakraborty, Sudip; Fernandes, Katia; Liebmann, Brant; Fisher, Rosie; Myneni, Ranga B.

    2013-01-01

    We have observed that the dry-season length (DSL) has increased over southern Amazonia since 1979, primarily owing to a delay of its ending dates (dry-season end, DSE), and is accompanied by a prolonged fire season. A poleward shift of the subtropical jet over South America and an increase of local convective inhibition energy in austral winter (June–August) seem to cause the delay of the DSE in austral spring (September–November). These changes cannot be simply linked to the variability of the tropical Pacific and Atlantic Oceans. Although they show some resemblance to the effects of anthropogenic forcings reported in the literature, we cannot attribute them to this cause because of inadequate representation of these processes in the global climate models that were presented in the Intergovernmental Panel on Climate Change’s Fifth Assessment Report. These models significantly underestimate the variability of the DSE and DSL and their controlling processes. Such biases imply that the future change of the DSE and DSL may be underestimated by the climate projections provided by the Intergovernmental Panel on Climate Change’s Fifth Assessment Report models. Although it is not clear whether the observed increase of the DSL will continue in the future, were it to continue at half the rate of that observed, the long DSL and fire season that contributed to the 2005 drought would become the new norm by the late 21st century. The large uncertainty shown in this study highlights the need for a focused effort to better understand and simulate these changes over southern Amazonia. PMID:24145443

  16. 48 CFR 25.702 - Prohibition on contracting with entities that conduct restricted business operations in Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Prohibition on contracting with entities that conduct restricted business operations in Sudan. 25.702 Section 25.702 Federal... operations in Sudan....

  17. 48 CFR 25.702 - Prohibition on contracting with entities that conduct restricted business operations in Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Prohibition on contracting with entities that conduct restricted business operations in Sudan. 25.702 Section 25.702 Federal... operations in Sudan....

  18. 48 CFR 25.702 - Prohibition on contracting with entities that conduct restricted business operations in Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Prohibition on contracting with entities that conduct restricted business operations in Sudan. 25.702 Section 25.702 Federal... operations in Sudan....

  19. 48 CFR 25.702 - Prohibition on contracting with entities that conduct restricted business operations in Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Prohibition on contracting with entities that conduct restricted business operations in Sudan. 25.702 Section 25.702 Federal... operations in Sudan....

  20. 48 CFR 25.702 - Prohibition on contracting with entities that conduct restricted business operations in Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Prohibition on contracting with entities that conduct restricted business operations in Sudan. 25.702 Section 25.702 Federal... operations in Sudan....

  1. N Isotopes in Nile Sediments (ethiopia, Sudan)

    NASA Astrophysics Data System (ADS)

    Padoan, M.; Villa, I. M.; Garzanti, E.; Galbusera, M.; Quistini, S.; Peruta, L.; El Kammar, A.

    2009-04-01

    , values vary from 0.51240-0.51242 for tributaries draining basement rocks only (e.g., Gash, wadi Guba) to 0.51275-0.51280 for tributaries draining mostly basaltic rocks (Atbara); tributaries draining both record mixed signals (e.g., 0.51259; Beles). Nd ratios for Atbara sediments correspond closely with signatures of volcanic source rocks (0.51271-0.51298; Pik et al., 1999), revealing involvement of various mantle and crustal components in petrogenesis of flood basalts. Corresponding Nd model ages (tDM) cluster around 0.84 Ga for the mostly volcanic-derived Blue Nile, Atbara, and Main Nile muds, range 1.2 - 1.5 Ga for tributaries draining Ethiopian basement rocks, and reach as high as 2.4 Ga for the Bahr Ez Zeraf. The different Nd isotopic signal between mud and sand samples is closely controlled by mineralogical composition, Nd and other REE being chiefly contributed by ultradense minerals (e.g., monazite), and consequently concentrated in the finest size fractions of each sample (Garzanti et al., 2008). FREYDIER, R., MICHARD, A., DE LANGE G., THOMSON, J., 2001. Nd isotopic composition of Eastern Mediterranean sediments: tracers of the Nile influence during sapropel S1 formation. Mar. Geol., 177, 45-62. GARZANTI, E., ANDÒ, S., VEZZOLI, G., ABDEL MEGID, A.A., EL KAMMAR, A., 2006. Petrology of Nile River sands (Ethiopian and Sudan): Sediment budgets and erosion patterns. Earth Planet. Sci. Lett., 252, 327-341. GARZANTI, E., ANDÒ, S., VEZZOLI, G., 2008. Settling-equivalence of detrital minerals and grain-size dependence of sediment composition. Earth Planet. Sci. Lett. 273, 138-151. HARLAVAN Y., GARZANTI, E., PADOAN, M., EL KAMMAR, A. Geochemical characterization of Nile River sands; Rare earth elements, Pb and Sr isotopes of the fine fraction. In preparation. KROM, M.D., CLIFF, R.A., EIJSINK, L.M., HERUT, B., CHESTER, R., 1999a. The characterisation of Saharan dusts and Nile particulate matter in surface sediments from the Levantine basin using Sr isotopes. Mar. Geol

  2. Evaluation of anisotropy in physical/mechanical properties of metabasalts from Gadag (Southern India) - implications for vein emplacement and gold mineralization

    NASA Astrophysics Data System (ADS)

    Satheesan Vishnu, C.; Mamtani, Manish A.

    2016-04-01

    . This anisotropy of strength is a proof of the difference in physical property of the metabasalts with respect to magnetic foliation. This is also manifested in the result of P-wave velocity measurements, which is lower perpendicular (˜5000 m/s) to foliation than parallel (˜5700 m/s) to it. These results imply that the foliation developed during D1/D2 regional deformation dilated during D3 and resulted in emplacement of quartz veins, some of which are gold bearing. References: Mondal, T.K., Mamtani, M.A. (2013). 3-D Mohr circle construction using vein orientation data from Gadag (southern India) - implications to recognize fluid pressure fluctuation. Journal of Structural Geology 56, 45-56. Mondal, T.K., Mamtani, M.A. (2014). Fabric analysis in massive rocks of the Gadag region (southern India) - implications to decipher time relationship between regional deformation and gold mineralization. Tectonophysics 629, 238-249. Vishnu, C.S., Mamtani, M.A., Basu, A. (2010). AMS, ultrasonic P-wave velocity and rock strength analysis in quartzites devoid of mesoscopic foliations - implications for rock mechanics studies. Tectonophysics 494, 191-200.

  3. First field identification of the Cuonadong dome in southern Tibet: implications for EW extension of the North Himalayan gneiss dome

    NASA Astrophysics Data System (ADS)

    Fu, Jiangang; Li, Guangming; Wang, Genhou; Huang, Yong; Zhang, Linkui; Dong, Suiliang; Liang, Wei

    2016-07-01

    The Cuonadong dome exposes in east-southern margin of the North Himalayan gneiss domes (NHGD), which is reported first time in this study. The Cuonadong dome is located at the southern part of the Zhaxikang ore concentration area, which is divided into three tectono-lithostratigraphic units by two curved faults around the dome geometry from upper to lower (or from outer to inner): the upper unit, middle unit and lower unit, and the outer fault is Nading fault, while the inner fault is Jisong fault. The Cuonadong dome is a magmatic orthogneiss and leucogranite mantled by orthogneiss and metasedimentary rocks, which in turn are overlain by Jurassic metasedimentary and sedimentary rocks. The grades of metamorphism and structural deformation increase towards the core, which is correspondence with the Ridang Formation low-metamorphic schist, tourmaline granitic-biotite gneiss, garnet-mica gneiss and mylonitic quartz-mica gneiss. The Cuonadong dome preserves evidences for four major deformational events: firstly top-to-S thrust (D1), early approximately N-S extensional deformation (D2), main approximately E-W extensional deformation (D3), and late collapse structural deformation (D4) around the core of the Cuonadong dome, which are consistent to three groups lineation: approximately N-S-trending lineation including L1 and L2, E-W trending L3, and L4 with plunging towards outside of the dome, respectively. The formation of the Cuonadong dome was probably resulted from the main E-W extensional deformation which is a result of eastward flow of middle or lower crust from beneath Tibet accommodated by northward oblique underthrusting of Indian crust beneath Tibet. The establishment of the Cuonadong dome enhanced the E-W extension of the NHGD, which is further divided into two structural dome zones according to the different extensional directions: approximately N-S extensional North Himalayan gneiss domes (NS-NHGD) and E-W extensional North Himalayan gneiss domes (EW

  4. Regional variations in the lead isotopic composition of galena from southern Korea with implications for the discrimination of lead provenance

    NASA Astrophysics Data System (ADS)

    Jeong, Youn-Joong; Cheong, Chang-sik; Shin, Dongbok; Lee, Kwang-Sik; Jo, Hui Je; Gautam, Mukesh Kumar; Lee, Insung

    2012-11-01

    This study presents a comprehensive database (n = 215) of lead isotopes in galena from the southern Korean peninsula using new and published data. Of the 69 metal mines examined, predominantly skarn- and hydrothermal-type Pb-Zn-Au-Ag-Cu deposits were observed and were associated with Mesozoic magmatic activities. Galena samples from each geotectonic unit showed discrete lead isotopic signatures. The Gyeongsang basin samples were characteristically unradiogenic and had restricted variations in lead isotopic composition (206Pb/204Pb = 18.16-18.59, 207Pb/204Pb = 15.48-15.64, 208Pb/204Pb = 37.87-38.77). Their 208Pb/204Pb range indicated an involvement of source materials less thorogenic than the associated granites. The galena samples from Cambro-Ordovician carbonate rocks of the northeastern Yeongnam massif and eastern Taebaeksan basin had the most radiogenic 206Pb/204Pb (19.28 ± 0.14) and 207Pb/204Pb (15.833 ± 0.027) ratios. Their lead isotopic trend indicated a combined contribution of ore lead from granitic magmas, Precambrian basements, and overlain host rocks. Less radiogenic galena samples from the middle to southwestern parts of the Yeongnam massif and Okcheon belt showed limited lead isotopic variations (206Pb/204Pb = 18.332 ± 0.065, 207Pb/204Pb = 15.693 ± 0.012, 208Pb/204Pb = 38.93 ± 0.07 on average), probably resulted from mixing with a common crustal basement. The differences in lead isotopes between the radiogenic and unradiogenic groups from the Yeongnam massif and Okcheon belt may reflect the spatial dissimilarity of involved crustal rocks. The old crust appears to have significantly contributed ore lead to galenas from the western Gyeonggi massif, but the geochronological meaning of their steep 207Pb/204Pb-206Pb/204Pb trend is not clear. The comprehensive database constructed by the present study suggests that lead province in the southern Korean peninsula may be subdivided into four discrete zones. Linear discriminant analysis showed that more

  5. Multi-decadal variability and trends in the El Niño-Southern Oscillation and tropical Pacific fisheries implications

    NASA Astrophysics Data System (ADS)

    Harrison, D. E.; Chiodi, Andrew M.

    2015-03-01

    Extremes of the El Niño-Southern Oscillation (ENSO) are known to have various socio-economic impacts, including effects on several Pacific fisheries. The 137-year-long record of Darwin sea-level pressure offers a uniquely long-term perspective on ENSO and provides important insight into various aspects of interannual to century-scale variability that affects these fisheries. One particular issue of interest is whether there is a centennial-scale (or longer) trend that can be expected to alter the future distributions of these fisheries. Since most tropical Pacific fishery records are no longer than a few decades, another issue is the extent to which trends over these recent decades are a good basis for detecting the presence of long-term (e.g., centennial-scale) deterministic changes, and perhaps thereby projecting future conditions. We find that the full 137-yr trend cannot be distinguished from zero with 95% confidence, and also that the ENSO variance in recent decades is very similar to that of the early decades of the record, suggesting that ENSO has not fundamentally changed over the period of large increase in atmospheric CO2. However, the strong multi-decadal variability in ENSO is reflected in decades with quite different levels of ENSO effects on the ecosystem. Many multi-decadal subsets of the full record have statistically significant trends, using standard analysis techniques. These multi-decadal trends are not; however, representative of the record-length trend, nor are they a useful basis for projecting conditions in subsequent decades. Trend statistical significance is not a robust foundation for speculation about the future. We illustrate how the difficulties involved in determining whether a trend is statistically significant or not mean that, even after careful consideration, an unexpectedly large number of trends may reach standard statistical significance levels over the time spans for which many newer records are available, but still not

  6. Volatile organic compounds from vegetation in southern Yunnan Province, China: Emission rates and some potential regional implications

    NASA Astrophysics Data System (ADS)

    Geron, Chris; Owen, Sue; Guenther, Alex; Greenberg, Jim; Rasmussen, Rei; Hui Bai, Jian; Li, Qing-Jun; Baker, Brad

    Little information is currently available regarding emissions of biogenic volatile organic compounds (BVOCs) in southern Asia. To address the need for BVOC emission estimates in regional atmospheric chemistry simulations, 95 common plant species were screened for emissions of BVOC in and near the Xishuangbanna Tropical Biological Gardens in southern Yunnan Province, Peoples' Republic of China in February 2003. In situ measurements with leaf cuvettes and branch bag enclosures were used in combination with portable gas chromatography, flame ionization, photoionization, and mass spectral detection to identify and quantify BVOC emissions. Forty-four of the species examined emitted isoprene at rates exceeding 20 μg C g -1 (leaf dry weight) h -1. An emphasis was placed on the genus Ficus, which is important in the region and occupies a wide range of ecological niches. Several species in the footprint of a nearby flux tower were also examined. Several palm species and an abundant fern ( Cyclosorus parasiticus) emitted substantial amounts of isoprene, and probably accounted for observed daytime mean isoprene fluxes from the understory of a Hevea brasiliensis plantation of 1.0 and 0.15 mg C m -2 h -1 during the wet and dry seasons, respectively. These measurements verify that both the forest floor and canopy in this region can be sources of isoprene. Monoterpene emissions exceeded 1.0 μg-C g -1 (leaf dry weight) h -1 from only 4 of 38 species surveyed, including some Ficus species and H. brasiliensis. However most of the trees of the latter species were sparsely foliated due to dry season senescence, and emission factors are approximately an order of magnitude lower than those reported during the wet season. BVOC emission rates and physiology of many species are impacted by reduced moisture availability, especially Mangifera indica. South Asia is a region undergoing rapid landuse change and forest plantation establishment, with large increases in area of high BVOC

  7. Petrography and geochemistry of the Arroyo de la Virgen and Isla Mala plutons, southern Uruguay: Early proterozoic tectonic implications

    NASA Astrophysics Data System (ADS)

    Preciozzi, F.; Bourne, J. H.

    1992-10-01

    The Arroyo de la Virgen pluton (AVP) and the Isla Mala pluton (IMP) are relatively small zoned intrusions of Early Proterozoic age. Radiometric age determinations suggest that the IMP is a composite pluton. The composition of the AVP ranges from granodiorite to leucogranite, whereas that of the IMP ranges from hornblendite to leucogranite. Both intrusions feature hornblende (with relict clinopyroxene cores) and biotite as mafic minerals. Muscovite and garnet are present in the most evolved members of each suite. Development of secondary chlorite, epidote, and sericite is common. Quartz typically has undulose extinction. The plutons are massive except near the margins of the intrusion. Both intrusions feature a calc-alkaline chemistry, have peraluminous indices of approximately 1.0, and were emplaced at relatively high levels in the crust. Application of several tectonic discriminant diagrams suggests that the IMP formed in an active continental-margin type of tectonic environment, whereas the AVP is a subalkaline, post-orogenic pluton. The ages of the IMP leucogranite and the AVP are similar (2290 and 2225 Ma, respectively). The age of the IMP leucogranite represents the minimum reliable age of the principal metamorphic event in southern Uruguay. A number of small dikes were emplaced into both intrusions approximately 300 million years later and represent a distinct phase of intrusive activity in the region.

  8. A New Oviraptorid Dinosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleobiogeographical Implications.

    PubMed

    Lü, Junchang; Pu, Hanyong; Kobayashi, Yoshitsugu; Xu, Li; Chang, Huali; Shang, Yuhua; Liu, Di; Lee, Yuong-Nam; Kundrát, Martin; Shen, Caizhi

    2015-01-01

    The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally. The position of the anteroventral corner of the external naris in relation to the posterodorsal corner of the antorbital fenestra provides new insight into the craniofacial evolution of oviraptorosaurid dinosaurs. A phylogenetic analysis recovers the new taxon as closely related to the Mongolian Citipati. Six oviraptorid dinosaurs from the Nanxiong Formation (Ganzhou and Nanxiong) are distributed within three clades of the family. Each of the three clades from the Nanxiong Formation has close relatives in Inner Mongolia and Mongolia, and in both places each clade may have had a specific diet or occupied a different ecological niche. Oviraptorid dinosaurs were geographically widespread across Asia in the latest Cretaceous and were an important component of terrestrial ecosystems during this time. PMID:26133245

  9. The Extent and Nature of Fluidity in Typologies of Female Sex Work in Southern India: Implications for HIV Prevention Programs.

    PubMed

    Jain, Anrudh K; Saggurti, Niranjan

    2012-04-01

    These authors examine the nature and extent of fluidity in defining the typology of female sex work based on the place of solicitation or place of sex or both places together, and whether sex workers belonging to a particular typology are at increased risk of HIV in southern India. Data are drawn from a cross-sectional survey conducted during 2007-2008 among mobile female sex workers (N = 5301) in four Indian states. Findings from this study address an important policy issue: Should programmatic prevention interventions be spread to cover all places of sex work or be focused on a few places that cover a large majority of sex workers? Results indicate that most female sex workers, including those who are usually hard to reach such as those who are mobile or who use homes for soliciting clients or sex, can be reached programmatically multiple times by concentrating on a smaller number of categories, such as street-, lodge-, and brothel-based sex workers. PMID:22745597

  10. A New Oviraptorid Dinosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleobiogeographical Implications

    PubMed Central

    Lü, Junchang; Pu, Hanyong; Kobayashi, Yoshitsugu; Xu, Li; Chang, Huali; Shang, Yuhua; Liu, Di; Lee, Yuong-Nam; Kundrát, Martin; Shen, Caizhi

    2015-01-01

    The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally. The position of the anteroventral corner of the external naris in relation to the posterodorsal corner of the antorbital fenestra provides new insight into the craniofacial evolution of oviraptorosaurid dinosaurs. A phylogenetic analysis recovers the new taxon as closely related to the Mongolian Citipati. Six oviraptorid dinosaurs from the Nanxiong Formation (Ganzhou and Nanxiong) are distributed within three clades of the family. Each of the three clades from the Nanxiong Formation has close relatives in Inner Mongolia and Mongolia, and in both places each clade may have had a specific diet or occupied a different ecological niche. Oviraptorid dinosaurs were geographically widespread across Asia in the latest Cretaceous and were an important component of terrestrial ecosystems during this time. PMID:26133245

  11. Paleoecological and Taphonomic Implications of Insect-Damaged Pleistocene Vertebrate Remains from Rancho La Brea, Southern California

    PubMed Central

    Holden, Anna R.; Harris, John M.; Timm, Robert M.

    2013-01-01

    The La Brea Tar Pits, the world’s richest and most important Late Pleistocene fossil locality, offers unsurpassed insights into southern California’s past environments. Recent studies at Rancho La Brea document that insects serve as sensitive and valuable paleoecological and taphonomic indicators. Of the thousands of fossil bird and mammal bones recovered from the Tar Pits, insect trace damage is thus far almost exclusively confined to the foot bones of large herbivores, especially bison, camel, and horse species. Our laboratory experiments with dermestid and tenebrionid beetles establish that the larvae of both consume bone, producing different characteristic feeding traces and providing the first documentation that tenebrionids consume bone. The presence of carcass-exploiting insects in the Rancho La Brea biota provides insight into the taphonomy of the asphaltic bone masses and the environmental conditions under which they accumulated. The succession of dermestids, tenebrionids, and indeterminate traces on many of the foot elements, combined with the climate restrictions and life cycles of these insects, indicate that carcasses could remain unsubmerged for at least 17–20 weeks, thus providing the most reliable estimate to date. Attribution of these traces also suggests that the asphaltic fossils only accumulated during warmer intervals of the Late Pleistocene. Forensic studies need to reevaluate the role of tenebrionids in carcass decomposition and other additional insects that modify bone. PMID:23843988

  12. Evidence for Alleghenian brine migration in the central and southern Appalachians: implications for Mississippi valley-type sulfide mineralization

    SciTech Connect

    Hearn, P.P.; Sutter, J.F.; Kunk, M.J.; Belkin, H.E.

    1985-01-01

    Authigenic K-feldspar has been found in rocks near Mississippi Valley-Type (MVT) sulfide mineralization in lower Paleozoic carbonate rocks of Pennsylvania, Maryland, Virginia, and Tennessee. Synthetic /sup 40/Ar//sup 39/Ar age spectra for the authigenic K-feldspar yield Carboniferous ages. Mass balance calculations indicate that the formation of the K-feldspar involved the flux of multiple pore volumes of fluid through the rocks. Estimates of vapor-liquid ratios and microthermometric homogenization temperatures of primary fluid inclusions in K-feldspar overgrowths, the presence of halite daughter crystals in some associated carbonate-hosted inclusions, and low whole-rock Cl/Br ratios indicate the K-feldspar formed by the interaction of connate brines with siliciclastic debris at temperatures between 100/sup 0/ and 200/sup 0/C. The common occurrence of feldspathized rocks stratigraphically below mineralized zones and the similarity of primary fluid inclusions in K-feldspar overgrowths to those observed in ore and qanque minerals suggest the authigenic K-feldspar and mineralization are coeval. The Carboniferous age suggested by /sup 40/Ar//sup 39/Ar age spectra is consistent with estimates based on (1) paleomagnetic studies and (2) analyses of sphalerite deformation fabrics. Accordingly, the authors suggest that MVT sulfide deposits in the central and southern Appalachians were emplaced by the migration of heated connate brines along structural pathways developed during the Alleghenian Orogeny.

  13. Interaction of ambient conditions and fecal coliform bacteria in southern Lake Michigan beach waters: Monitoring program implications

    USGS Publications Warehouse

    Whitman, Richard L.; Nevers, Meredith Becker; Gerovac, Paul J.

    1999-01-01

    Excessive fecal coliform bacteria in public swimming waters can potentially threaten visitor health. Fecal coliform bacteria (1984-1989) and Escherichia coli (1990-1995) density were monitored weekly at the Indiana Dunes National Lakeshore beaches for 12 summers, and park officials closed swimming areas when fecal coliform density exceeded the state water quality criteria (400 CFU fecal coliforms/ 100 ml; 235 CFU E. coli/100 ml water). Due to a 24-hour incubation in the fecal coliform and E. coli assays, beaches were closed the day after collection of high fecal coliform. Our analysis suggests that it is not possible to predict one day's fecal coliform count based on the previous day's results in waters taken from southern Lake Michigan beaches. Dispersal and deposition of bacteria were not uniform among sites or across time apparently due to interactions among environmental variables including rainfall, wind direction, water temperature, and bacteria source. Rainfall combined with northwest winds increased bacteria concentrations. Escherichia coli followed a seasonal trend with similar fluctuations in density among beaches. We suggest that the current beach monitoring protocol is inadequate for predicting fecal coliform density at the time of beach closure, and, subsequently, its use for ensuring visitor safety remains questionable.

  14. Geophysical interpretation of the gneiss terrane of northern Washington and southern British Columbia, and its implications for uranium exploration

    USGS Publications Warehouse

    Cady, John W.; Fox, Kenneth F.

    1984-01-01

    The Omineca crystalline belt of northeastern Washington and southern British Columbia has a regional Bouguer gravity high, and individual gneiss domes within the terrane are marked by local gravity highs. Models of crustal structure that satisfy the limited available seismic-refraction data and explain the gravity high over the gneiss terrane permit the hypothesis that the core metamorphic complexes are the surface expression of a zone of dense infrastructure that makes up the upper 20 km (kilometers) of the crust within the crystalline belt. The Omineca crystalline belt is characterized regionally by low aeromagnetic relief. The gneiss domes and biotite- and biotite-muscovite granites are generally marked by low magnetic relief, whereas hornblende-biotite granites often cause magnetic highs. Exceptional magnetic highs mark zones of magnetic rock within the biotite- and biotite-muscovite granites and the gneiss domes; these areas are worthy of study, both to determine the origin and disposition of the magnetite and to explore the possible existence of uraniferous magnetite deposits.

  15. Deposits of the most recent eruption in the Southern Mono Craters, California: Description, interpretation and implications for regional marker tephras

    NASA Astrophysics Data System (ADS)

    Bursik, Marcus; Sieh, Kerry; Meltzner, Aron

    2014-04-01

    The penultimate eruption in the Mono Craters, Mono County, CA, USA, occurred in the southern section of the volcanic chain, and is herein named the South Mono eruption. The South Mono eruption occurred in 594-648cal A.D., and its products consist of widespread Plinian and phreatomagmatic fall, surge and pyroclastic flow deposits. The explosive deposits can be broken into Basal, Orange-Brown (surge dominated) and Upper subunits. The eruptive phase represented by the Upper beds was the most intense and voluminous, dispersing tephra over a wide region of eastern CA and western NV. South Coulee was the only effusive product of the eruption, and comprises the vast majority of the c. 0.4 cu km dense-rock equivalent (DRE) volume. The tephra overlies the deposits of Wilson Butte to the south, and is correlated herein with Wood's Tephra 2, and Walker Lake and Turupah Flats regional marker tephra layers. Other dates for these regional tephras may be the result of dating ash redeposited in debris flow events following fire.

  16. Limited MHC polymorphism in the southern elephant seal: implications for MHC evolution and marine mammal population biology.

    PubMed

    Slade, R W

    1992-08-22

    Genes of the major histocompatibility complex (MHC) are highly polymorphic in most terrestrial mammal populations so far studied. Exceptions to this are typically populations that lack genome-wide diversity. Here I show that two populations of the southern elephant seal (Mirounga leonina) have low DNA restriction fragment length polymorphism at MHC loci when compared with terrestrial mammals. Limited studies on MHC polymorphism in two cetacean species suggest this is a feature of marine mammal populations in general. MHC polymorphism is thought to be maintained by balancing selection, and several types of disease-based and reproductive-based mechanisms have been proposed. For the three marine mammal species examined, the low MHC polymorphism cannot be explained by low genome-wide diversity, or by any reproductive-based selection pressure. It can, however, be explained by diminished exposure to pathogenic selection pressure compared with terrestrial mammals. Reduced exposure to pathogens would also mean that marine mammal populations may be susceptible to occasional pathogen-induced mass mortalities. PMID:1360677

  17. A New Oviraptorid Dinosaur (Dinosauria: Oviraptorosauria) from the Late Cretaceous of Southern China and Its Paleobiogeographical Implications

    NASA Astrophysics Data System (ADS)

    Lü, Junchang; Pu, Hanyong; Kobayashi, Yoshitsugu; Xu, Li; Chang, Huali; Shang, Yuhua; Liu, Di; Lee, Yuong-Nam; Kundrát, Martin; Shen, Caizhi

    2015-07-01

    The Ganzhou area of Jiangxi Province, southern China is becoming one of the most productive oviraptorosaurian localities in the world. A new oviraptorid dinosaur was unearthed from the uppermost Upper Cretaceous Nanxiong Formation of Ganzhou area. It is characterized by an anterodorsally sloping occiput and quadrate (a feature shared with Citipati), a circular supratemporal fenestra that is much smaller than the lower temporal fenestra, and a dentary in which the dorsal margin above the external mandibular fenestra is strongly concave ventrally. The position of the anteroventral corner of the external naris in relation to the posterodorsal corner of the antorbital fenestra provides new insight into the craniofacial evolution of oviraptorosaurid dinosaurs. A phylogenetic analysis recovers the new taxon as closely related to the Mongolian Citipati. Six oviraptorid dinosaurs from the Nanxiong Formation (Ganzhou and Nanxiong) are distributed within three clades of the family. Each of the three clades from the Nanxiong Formation has close relatives in Inner Mongolia and Mongolia, and in both places each clade may have had a specific diet or occupied a different ecological niche. Oviraptorid dinosaurs were geographically widespread across Asia in the latest Cretaceous and were an important component of terrestrial ecosystems during this time.

  18. Plio-Pleistocene vegetation response on orbitally forced climatic cycles in Southern Europe - implications for early human environments

    NASA Astrophysics Data System (ADS)

    Bruch, Angela; Bertini, Adele

    2013-04-01

    The pace and causes of the early human colonization, in one or several migratory waves from Africa in new environments of the Eurasian continent during the Early Pleistocene, are still a matter of debate. However, climate change is considered a major driving factor of hominin evolution and dispersal patterns. In fact directly or indirectly by its severe influence on vegetation, physiography of landscape, and animal distribution, climate modulates the availability of resources. Plant fossils usually are rare or even absent at hominin sites. Thus, direct evidence on local vegetation and environment is generally missing. Independent from such localities, pollen profiles from the Mediterranean realm show the response of regional vegetation on global climate changes and cyclicity, with distinct spatial and temporal differences. Furthermore, plant fossils provide proxies for climate quantification that can be compared to the global signal, and add data to understanding the regional differentiation of Mediterranean environments. In this presentation we will discuss various palaeobotanical data from Southern Europe to assess Early Pleistocene climate and vegetation in time and space as part of the environment during the first expansions of early humans out of Africa.

  19. Magnetotelluric constraints on the fluid content in the upper mantle beneath the southern Canadian Cordillera: Implications for rheology

    NASA Astrophysics Data System (ADS)

    Rippe, Dennis; Unsworth, Martyn J.; Currie, Claire A.

    2013-10-01

    Long-period magnetotelluric data were collected on two parallel profiles extending across the southern Canadian Cordillera and used to derive models of the electrical resistivity of the crust and mantle from the Cascadia subduction zone to the Alberta Basin. In the fore arc, the resistivity models indicate an east dipping conductor and conductive mantle wedge, caused by the release of aqueous fluids from the Juan de Fuca plate. Low resistivities are also found beneath the volcanic arc, associated with water released from the subducting slab and mantle melts. Low resistivities in the back-arc upper mantle at depths less than 60 km suggest a shallow asthenosphere compared to the adjacent North American craton where the lithosphere-asthenosphere boundary is at ~200 km. The resistivity of the back-arc upper mantle was interpreted using geotherms, laboratory studies of mineral properties and melting points to determine the type and quantity of fluids present. The low resistivities in the back-arc upper mantle require aqueous fluids, with water content increasing from 0.005 wt % at 50 km to 0.03 wt % at 150 km depth. In addition, melt fractions of up to 1.5% are required at depths less than ~135 km to explain the observed resistivities. The presence of these quantities of aqueous fluids and partial melt will lower the viscosity of the upper mantle, as required by geodynamic models that include vigorous convection in the back arc to explain the observed heat flow.

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

    NASA Astrophysics Data System (ADS)

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

    2014-07-01

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

  1. Crustal structure of Precambrian terranes in the southern African subcontinent with implications for secular variation in crustal genesis

    NASA Astrophysics Data System (ADS)

    Kachingwe, Marsella; Nyblade, Andrew; Julià, Jordi

    2015-07-01

    New estimates of crustal thickness, Poisson's ratio and crustal shear wave velocity have been obtained for 39 stations in Angola, Botswana, the Democratic Republic of Congo, Malawi, Mozambique, Namibia, Rwanda, Tanzania and Zambia by modelling P-wave receiver functions using the H-κ stacking method and jointly inverting the receiver functions with Rayleigh-wave phase and group velocities. These estimates, combined with similar results from previous studies, have been examined for secular trends in Precambrian crustal structure within the southern African subcontinent. In both Archean and Proterozoic terranes we find similar Moho depths [38-39 ± 3 km SD (standard deviation)], crustal Poisson's ratio (0.26 ± 0.01 SD), mean crustal shear wave velocity (3.7 ± 0.1 km s-1 SD), and amounts of heterogeneity in the thickness of the mafic lower crust, as defined by shear wave velocities ≥4.0 km s-1. In addition, the amount of variability in these crustal parameters is similar within each individual age grouping as between age groupings. Thus, the results provide little evidence for secular variation in Precambrian crustal structure, including between Meso- and Neoarchean crust. This finding suggests that (1) continental crustal has been generated by similar processes since the Mesoarchean or (2) plate tectonic processes have reworked and modified the crust through time, erasing variations in structure resulting from crustal genesis.

  2. Presence of Zea luxurians (Durieu and Ascherson) Bird in Southern Brazil: Implications for the Conservation of Wild Relatives of Maize

    PubMed Central

    2015-01-01

    Records of the occurrence of wild relatives of maize in South American lowlands are unprecedented, especially in sympatric coexistence with landraces. This fact is relevant, because regions of occurrence of wild relatives of cultivated plants should be a priority for conservation, even if they do not correspond to the center of origin of the species. The aim of this study was to identify and characterize the wild relatives of maize in the Far West of Santa Catarina, southern Brazil. Therefore, phenotypic characterization was performed for five populations, based on 22 morphological traits deemed as fundamental for classifying the species of the genus Zea, and validated through the characterization of chromosomal knobs of two populations. The occurrence and distribution of teosinte populations were described through semi-structured interviews applied to a sample of 305 farmers. A total of 136 teosinte populations were identified; 75% of them occur spontaneously, 17% are cultivated populations, and 8% occur both ways, for the same farm. Populations that were characterized morphologically had trapezoidal fruits mostly, upright tassel branch (4–18), non-prominent main branch and glabrous glumes, with two protruding outer ribs and 8 inner ribs, on average. Cytogenetic analysis identified 10 pairs of homologous chromosomes (2n = 20) with 26 knobs, located in the terminal region of all chromosomes. The similarity of these results with the information reported in the literature indicates that the five populations of wild relatives of maize in this region of Santa Catarina belong to the botanical species Zea luxurians. PMID:26488577

  3. Stable isotopes in cave drip waters from the semi-arid southern Portugal: implication for paleoenvironment reconstructions

    NASA Astrophysics Data System (ADS)

    Veiga-Pires, Cristina; Hélie, Jean-François; Hillaire-Marcel, Claude

    2014-05-01

    Paleo-environmental studies rely on proxies for which present day conditions need to be documented. Here, we present results from a nearly two years sampling program of waters in precipitation, aquifers and cave drip waters in the semi arid region of Southern Portugal where a Mediterranean type climate prevails. Isotopic compositions of precipitations at Faro, from 1978 until 2001, are available through the Global Network of Isotopes in Precipitation (GNIP) database of the International Atomic Energy Agency. In addition, we measured oxygen and hydrogen isotopic compositions of water samples collected in 2011 and 2012 at one meteorological station located 20 km apart from the cave. In the cave itself, four different dripping locations were surveyed. Finally, five wells from the aquifer flowing underneath the cave were also sampled. Whereas local meteoric water line obtained from GNIP data shows an important contribution of local evaporating waters, precipitation data from this project rather points out to a drier moisture source, exhibiting a deuterium excess of close to 16.5 oȦquifer isotopic compositions show very small variations during the 2 yr sampling period, with mean values of -4.53±0.06 o (VSMOW) and 23.39±0.81 o (VSMOW) for δ18O and δ2H, respectively. On the other hand, drip waters isotopic compositions are dependent of the sampling site, although varying linearly (δ2H~13.3*δ18O + 38.1, R2=0.74, p

  4. Improved Schmidt-hammer exposure ages for active and relict pronival ramparts in southern Norway, and their palaeoenvironmental implications

    NASA Astrophysics Data System (ADS)

    Matthews, John A.; Wilson, Peter

    2015-10-01

    Eight pronival (protalus) ramparts from alpine southern Norway were dated using Schmidt-hammer exposure-age dating (SHD) based on local high-precision linear calibration equations. SHD ages were - 1355 ± 1240 to 815 ± 1000 years for three active ramparts and 8730 ± 1050 to 14,635 ± 1060 years for five relict ramparts. Different parts of the same rampart yielded ages that were in generally good agreement. R-value frequency distributions enabled the identification single-age and mixed-age boulder populations, and the differentiation of active and relict rampart surfaces. The relict ramparts are located outside Younger Dryas glacier limits and probably formed over a period of ~ 6000 years between deglaciation (following the Last Glacial Maximum of the late Weichselian, ~ 18,000 years ago) and the end of the Younger Dryas (~ 11,700 years ago). At that time, glacial debuttressing and permafrost degradation apparently enhanced the release of rock debris from rock faces to the ramparts. The active ramparts, which are located in areas deglaciated after the Younger Dryas, are relatively uncommon in the study area due to diminished paraglacial effects and limited debris supply associated with seasonally frozen ground during the Holocene. Thus, the legacy of glaciers, glacier-permafrost interaction, and the specific type of periglacial environment must all be considered when assessing the palaeoenvironmental and palaeoclimatic significance of pronival ramparts.

  5. 31 CFR 538.208 - Prohibited grant or extension of credits or loans to the Government of Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... credits or loans to the Government of Sudan. 538.208 Section 538.208 Money and Finance: Treasury... loans to the Government of Sudan. Except as otherwise authorized, the grant or extension of credits or loans by any United States person to the Government of Sudan is prohibited....

  6. 31 CFR 538.208 - Prohibited grant or extension of credits or loans to the Government of Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... credits or loans to the Government of Sudan. 538.208 Section 538.208 Money and Finance: Treasury... loans to the Government of Sudan. Except as otherwise authorized, the grant or extension of credits or loans by any United States person to the Government of Sudan is prohibited....

  7. 31 CFR 538.506 - 30-day delayed effective date for pre-November 4, 1997 trade contracts involving Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-November 4, 1997 trade contracts involving Sudan. 538.506 Section 538.506 Money and Finance: Treasury....506 30-day delayed effective date for pre-November 4, 1997 trade contracts involving Sudan. (a) Pre... of Sudanese origin or owned or controlled by the Government of Sudan, importations under the...

  8. 31 CFR 538.508 - Certain payments by the Government of Sudan of obligations to persons within the United States...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Sudan of obligations to persons within the United States authorized. 538.508 Section 538.508 Money and... Licensing Policy § 538.508 Certain payments by the Government of Sudan of obligations to persons within the..., solely for the purpose of payment of obligations of the Government of Sudan to persons or accounts...

  9. 31 CFR 538.508 - Certain payments by the Government of Sudan of obligations to persons within the United States...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Sudan of obligations to persons within the United States authorized. 538.508 Section 538.508 Money and... Licensing Policy § 538.508 Certain payments by the Government of Sudan of obligations to persons within the..., solely for the purpose of payment of obligations of the Government of Sudan to persons or accounts...

  10. 31 CFR 538.508 - Certain payments by the Government of Sudan of obligations to persons within the United States...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Sudan of obligations to persons within the United States authorized. 538.508 Section 538.508 Money and... Licensing Policy § 538.508 Certain payments by the Government of Sudan of obligations to persons within the..., solely for the purpose of payment of obligations of the Government of Sudan to persons or accounts...

  11. 31 CFR 538.208 - Prohibited grant or extension of credits or loans to the Government of Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... credits or loans to the Government of Sudan. 538.208 Section 538.208 Money and Finance: Treasury... loans to the Government of Sudan. Except as otherwise authorized, the grant or extension of credits or loans by any United States person to the Government of Sudan is prohibited....

  12. 31 CFR 538.506 - 30-day delayed effective date for pre-November 4, 1997 trade contracts involving Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-November 4, 1997 trade contracts involving Sudan. 538.506 Section 538.506 Money and Finance: Treasury....506 30-day delayed effective date for pre-November 4, 1997 trade contracts involving Sudan. (a) Pre... of Sudanese origin or owned or controlled by the Government of Sudan, importations under the...

  13. 31 CFR 538.506 - 30-day delayed effective date for pre-November 4, 1997 trade contracts involving Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-November 4, 1997 trade contracts involving Sudan. 538.506 Section 538.506 Money and Finance: Treasury....506 30-day delayed effective date for pre-November 4, 1997 trade contracts involving Sudan. (a) Pre... of Sudanese origin or owned or controlled by the Government of Sudan, importations under the...

  14. 31 CFR 538.208 - Prohibited grant or extension of credits or loans to the Government of Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... credits or loans to the Government of Sudan. 538.208 Section 538.208 Money and Finance: Treasury... loans to the Government of Sudan. Except as otherwise authorized, the grant or extension of credits or loans by any United States person to the Government of Sudan is prohibited....

  15. 31 CFR 538.508 - Certain payments by the Government of Sudan of obligations to persons within the United States...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Sudan of obligations to persons within the United States authorized. 538.508 Section 538.508 Money and... Licensing Policy § 538.508 Certain payments by the Government of Sudan of obligations to persons within the..., solely for the purpose of payment of obligations of the Government of Sudan to persons or accounts...

  16. 31 CFR 538.508 - Certain payments by the Government of Sudan of obligations to persons within the United States...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Sudan of obligations to persons within the United States authorized. 538.508 Section 538.508 Money and... Licensing Policy § 538.508 Certain payments by the Government of Sudan of obligations to persons within the..., solely for the purpose of payment of obligations of the Government of Sudan to persons or accounts...

  17. 31 CFR 538.204 - Prohibited importation of goods or services from Sudan.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Prohibited importation of goods or services from Sudan. 538.204 Section 538.204 Money and Finance: Treasury Regulations Relating to Money and... REGULATIONS Prohibitions § 538.204 Prohibited importation of goods or services from Sudan. Except as...

  18. 75 FR 67585 - Continuation of the National Emergency With Respect to Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-02

    ... the Congress. (Presidential Sig.) THE WHITE HOUSE, November 1, 2010. [FR Doc. 2010-27876 Filed 11-1-10... Notice of November 1, 2010--Continuation of the National Emergency With Respect to Sudan #0; #0; #0... National Emergency With Respect to Sudan On November 3, 1997, by Executive Order 13067, the...

  19. 31 CFR 538.204 - Prohibited importation of goods or services from Sudan.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false Prohibited importation of goods or services from Sudan. 538.204 Section 538.204 Money and Finance: Treasury Regulations Relating to Money and... REGULATIONS Prohibitions § 538.204 Prohibited importation of goods or services from Sudan. Except as...

  20. 31 CFR 538.204 - Prohibited importation of goods or services from Sudan.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Prohibited importation of goods or services from Sudan. 538.204 Section 538.204 Money and Finance: Treasury Regulations Relating to Money and... REGULATIONS Prohibitions § 538.204 Prohibited importation of goods or services from Sudan. Except as...

  1. 77 FR 3369 - Presidential Determination on the Eligibility of South Sudan To Receive Defense Articles and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-24

    ... HOUSE, Washington, January 6, 2012 [FR Doc. 2012-1545 Filed 1-23-12; 8:45 am] Billing code 4710-10-P ... the Eligibility of South Sudan To Receive Defense Articles and Defense Services Under the Foreign... defense services to the Republic of South Sudan will strengthen the security of the United States...

  2. 76 FR 68053 - Continuation of the National Emergency With Respect to Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ... Register and transmitted to the Congress. (Presidential Sig.) THE WHITE HOUSE, November 1, 2011. [FR Doc... With Respect to Sudan #0; #0; #0; Presidential Documents #0; #0; #0;#0;Federal Register / Vol. 76, No... ] Notice of November 1, 2011 Continuation of the National Emergency With Respect to Sudan On November...

  3. 31 CFR 538.204 - Prohibited importation of goods or services from Sudan.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Prohibited importation of goods or services from Sudan. 538.204 Section 538.204 Money and Finance: Treasury Regulations Relating to Money and... REGULATIONS Prohibitions § 538.204 Prohibited importation of goods or services from Sudan. Except as...

  4. 78 FR 16028 - Waiver of Restriction on Assistance to the Central Government of South Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Waiver of Restriction on Assistance to the Central Government of South Sudan Pursuant to Section 7031(b)(3... Section 7031(b)(1) of the Act with respect to South Sudan, and I hereby waive this restriction....

  5. 77 FR 66357 - Continuation of the National Emergency With Respect to Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-02

    ..., Washington, November 1, 2012. [FR Doc. 2012-27035 Filed 11-1-12; 2:15 pm] Billing code 3295-F3 ... With Respect to Sudan #0; #0; #0; Presidential Documents #0; #0; #0;#0;Federal Register / Vol. 77 , No... ] Notice of November 1, 2012 Continuation of the National Emergency With Respect to Sudan On November...

  6. 78 FR 65865 - Continuation of the National Emergency With Respect to Sudan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-01

    ..., October 30, 2013. [FR Doc. 2013-26413 Filed 10-31-13; 11:15 am] Billing code 3295-F4 ... With Respect to Sudan #0; #0; #0; Presidential Documents #0; #0; #0;#0;Federal Register / Vol. 78 , No... ] Notice of October 30, 2013 Continuation of the National Emergency With Respect to Sudan On November...

  7. 76 FR 63629 - Designation of Republic of South Sudan for Temporary Protected Status

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ... not yet affected South Sudan directly, food security is fragile and the living situation remains... SECURITY Citizenship and Immigration Services RIN 1615-ZB08 Designation of Republic of South Sudan for... Security. ACTION: Notice. SUMMARY: This Notice announces that the Secretary of Homeland Security...

  8. The Lost Boys of Sudan: Ambiguous Loss, Search for Family, and Reestablishing Relationships with Family Members

    ERIC Educational Resources Information Center

    Luster, Tom; Qin, Desiree B.; Bates, Laura; Johnson, Deborah J.; Rana, Meenal

    2008-01-01

    The "Lost Boys of Sudan" were separated from their families by civil war and subsequently lived in 3 other countries--Ethiopia, Kenya, and the United States. In-depth interviews were conducted with 10 refugees who located surviving family members in Sudan after an average separation of 13.7 years. The interviews probed their experiences of…

  9. Games, Social Simulations, and Data--Integration for Policy Decisions: The "Sudan" Game

    ERIC Educational Resources Information Center

    Landwehr, Peter; Spraragen, Marc; Ranganathan, Balki; Carley, Kathleen M.; Zyda, Michael

    2013-01-01

    In this article, the authors discuss the development of the "Sudan Game," an interactive model of the country in the time period leading up to the Sudanese referendum on the secession of the South. While many simulations are designed to educate about their subjects, the "Sudan Game" is intended to be a prototype for policy making via gameplay. It…

  10. Overcoming Structural Adjustment Policies in Africa: Strategies for Vocational Education and Training in the Sudan.

    ERIC Educational Resources Information Center

    Washi, Sidiga; Pitamber, Sunita

    Most developing countries have been debt ridden since the mid-1970s. This continuing debt burden has resulted in increasing prices and inflation, growing unemployment, and daily life difficulties. This problem has been acute for the Sudan. Sudan received help from the International Monetary Fund (IMF) in 1978 and negotiated new credit terms. By…

  11. The Birth of a Nation Is Only the Beginning: The Travails of South Sudan

    ERIC Educational Resources Information Center

    Totten, Samuel

    2014-01-01

    Just three years since it broke away from Sudan, the new country of South Sudan is embroiled in a violent civil war. This article examines what went wrong and why, by discussing the incredible difficulty of building a new nation from scratch following years of conflict, war, suspicion, and great expectations. How this tragedy will end is…

  12. Royal Society of Tropical Medicine and Hygiene joint meeting with Médecins Sans Frontières at Manson House, London, 20 March 2003: field research in humanitarian medical programmes. Médecins Sans Frontières interventions against kala-azar in the Sudan, 1989-2003.

    PubMed

    Ritmeijer, K; Davidson, R N

    2003-01-01

    Since 1989, Médecins Sans Frontières (MSF) has provided medical humanitarian assistance during outbreaks of visceral leishmaniasis (VL; kala-azar) in Sudan. First, in western Upper Nile in southern Sudan, where a VL epidemic occurred after the resumption of the civil war in Sudan in 1983, with an estimated 100,000 deaths. Later, MSF started interventions in eastern Upper Nile and Gedaref State. In these two endemic regions VL incidence has risen markedly since 2001, which could be the start of a new epidemic cycle. Outbreaks of VL in Sudan remain unpredictable, and access to affected populations in war-torn southern Sudan is often hampered by insecurity. Therefore, MSF takes a flexible approach, establishing treatment centres where patients can be accessed. From 1989 to 2002, MSF treated >51,000 VL cases in Sudan. Despite very basic field conditions, high cure rates of 95% are being achieved. Lack of diagnostics is a major obstacle to treatment, especially during epidemic situations. Therefore, development of simple and rapid technologies is required, allowing reliable diagnosis under field conditions. For treatment of VL there is a limited choice of effective, affordable drugs. There are strong indications of an emerging resistance to antimonials in Malakal. Introduction of combination therapies is urgently needed to prevent the further emergence and spread of resistance to antimonials, which are still the mainstay of VL treatment in eastern Africa. Experience with combination therapy with sodium stibogluconate (SSG) and paromomycin is promising, and combinations of SSg with liposomal amphotericin B and miltefosine are currently being explored. PMID:16134257

  13. Climatic Implications of the Observed Temperature Dependence of the Liquid Water Path of Low Clouds in the Southern Great Plains

    NASA Technical Reports Server (NTRS)

    DelGenio, Anthony

    1999-01-01

    Satellite observations of low-level clouds have challenged the assumption that adiabatic liquid water content combined with constant physical thickness will lead to a negative cloud optics feedback in a decadal climate change. We explore the reasons for the satellite results using four years of surface remote sensing data from the Atmospheric Radiation Measurement Program Cloud and Radiation Testbed site in the Southern Great Plains of the United States. We find that low cloud liquid water path is approximately invariant with temperature in winter but decreases strongly with temperature in summer, consistent with the satellite inferences at this latitude. This behavior occurs because liquid water content shows no detectable temperature dependence while cloud physical thickness decreases with warming. Thinning of clouds with warming is observed on seasonal, synoptic, and diurnal time scales; it is most obvious in the warm sectors of baroclinic waves. Although cloud top is observed to slightly descend with warming, the primary cause of thinning, is the ascent of cloud base due to the reduction in surface relative humidity and the concomitant increase in the lifting condensation level of surface air. Low cloud liquid water path is not observed to be a continuous function of temperature. Rather, the behavior we observe is best explained as a transition in the frequency of occurrence of different boundary layer types. At cold temperatures, a mixture of stratified and convective boundary layers is observed, leading to a broad distribution of liquid water path values, while at warm temperatures, only convective boundary layers with small liquid water paths, some of them decoupled, are observed. Our results, combined with the earlier satellite inferences, imply that the commonly quoted 1.5C lower limit for the equilibrium global climate sensitivity to a doubling of CO2 which is based on models with near-adiabatic liquid water behavior and constant physical thickness

  14. Climatic Implications of the Observed Temperature Dependence of the Liquid Water Path of Low Clouds in the Southern Great Plains

    NASA Technical Reports Server (NTRS)

    DelGenio, Anthony D.; Wolf, Audrey B.

    1999-01-01

    Satellite observations of low-level clouds have challenged the assumption that adiabatic liquid water content combined with constant physical thickness will lead to a negative cloud optics feedback in a decadal climate change. We explore the reasons for the satellite results using four years of surface remote sensing data from the Atmospheric Radiation Measurement Program Cloud and Radiation Testbed site in the Southern Great Plains of the United States. We find that low cloud liquid water path is approximately invariant with temperature in winter but decreases strongly with temperature in summer, consistent with the satellite inferences at this latitude. This behavior occurs because liquid water content shows no detectable temperature dependence while cloud physical thickness decreases with warming. Thinning of clouds with warming is observed on seasonal, synoptic, and diurnal time scales; it is most obvious in the warm sectors of baroclinic waves. Although cloud top is observed to slightly descend with warming, the primary cause of thinning is the ascent of cloud base due to the reduction in surface relative humidity and the concomitant increase in the lifting condensation level of surface air. Low cloud liquid water path is not observed to be a continuous function of temperature. Rather, the behavior we observe is best explained as a transition in the frequency of occurrence of different boundary layer types: At cold temperatures, a mixture of stratified and convective boundary layers is observed, leading to a broad distribution of liquid water path values, while at warm temperatures, only convective boundary layers with small liquid water paths, some of them decoupled, are observed. Our results, combined with the earlier satellite inferences, imply that the commonly quoted 1.50 C lower limit for the equilibrium global climate sensitivity to a doubling of CO2, which is based on models with near-adiabatic liquid water behavior and constant physical thickness

  15. Implications of topographic relief on the brittle-to-plastic boundary beneath the southern Central Range, Taiwan

    NASA Astrophysics Data System (ADS)

    Cavallotti, C. J.; Lewis, J. C.

    2015-12-01

    The result of the ongoing arc-continent collision between the Eurasian (EU) and Philippine Sea (PSP) plates, Taiwan is an important tool in understanding the real time mechanics of the mountain building process. We show an apparent gap in seismicity beneath Taiwan's Southern Central Range that may represent the presence of a volume of rock lacking the shear strength required to record brittle processes. A spatially accurate 3D map was created, utilizing data recorded for over 8000 seismic events beneath Taiwan and the surrounding area, and shows an elongate aseismic volume trending northeast southwest generally parallel to the topographic grain of the island. Published P-wave data shows an area nearly coincident with the aseismic zone with lower velocities at depths of 7.5km in the west to nearly 40km in the east which suggests a difference in density (and rheology) from the surrounding, seismically active, areas. Strain inversions assuming a micropolar model for crustal deformation suggest systematic changes in strain tensor geometry from east to west across the hypothesized density boundary. Preliminary results indicate that seismogenic strain along the western margin of the aseismic zone accommodates crustal thinning with stretching oblique to the orogen. In contrast, on the east side of the aseismic zone we see crustal thickening with minimum stretching (shortening) subparallel to PSP-EU motion. The profound change in strain geometry suggests that the asiesmic zone is a partially ductile volume of rock caused by interactions of the EU and PSP beneath Taiwan. We hypothesize that if the rheology contrast is sufficient, higher spatial resolution inversions may reveal that events near the seismic/aseismic interface exhibit Andersonian-like behavior wherein one principal strain axis would lie orthogonal at any given point to a surface mapped to this boundary. Alternatively, if the contrast is smaller the inverted strain geometries may vary systematically and provide

  16. Morphological properties of tunnel valleys of the southern sector of the Laurentide Ice Sheet and implications for their formation

    NASA Astrophysics Data System (ADS)

    Livingstone, Stephen J.; Clark, Chris D.

    2016-07-01

    Tunnel valleys have been widely reported on the bed of former ice sheets and are considered an important expression of subglacial meltwater drainage. Although known to have been cut by erosive meltwater flow, the water source and development of channels has been widely debated; ranging between outburst flood events through to gradually occurring channel propagation. We have mapped and analysed the spatial pattern and morphometry of tunnel valleys and associated glacial landforms along the southern sector of the former Laurentide Ice Sheet from high-resolution digital elevation models. Around 2000 tunnel valleys have been mapped, revealing an organised pattern of sub-parallel, semi-regularly spaced valleys that form in distinctive clusters. The tunnel valleys are typically < 20 km long, and 0.5-3 km wide, although their width varies considerably down-valley. They preferentially terminate at moraines, which suggests that formation is time dependent; while we also observe some tunnel valleys that have grown headwards out of hill-hole pairs. Analysis of cross-cutting relationships between tunnel valleys, moraines and outwash fans permits reconstruction of channel development in relation to the retreating ice margin. This palaeo-drainage reconstruction demonstrates incremental growth of most valleys, with some used repeatedly or for long periods, during deglaciation, while others were abandoned shortly after their formation. Our data and interpretation support gradual (rather than a single-event) formation of most tunnel valleys with secondary contributions from flood drainage of subglacial and or supraglacially stored water down individual tunnel valleys. The distribution and morphology of tunnel valleys is shown to be sensitive to regional factors such as basal thermal regime, ice and bed topography, timing and climate.

  17. Controls on large landslide distribution and implications for the geomorphic evolution of the southern interior Columbia River basin

    USGS Publications Warehouse

    Safran, E.B.; Anderson, S.W.; Mills-Novoa, M.; House, P.K.; Ely, L.

    2011-01-01

    Large landslides (>0.1 km2) are important agents of geomorphic change. While most common in rugged mountain ranges, large landslides can also be widespread in relatively low-relief (several 100 m) terrain, where their distribution has been relatively little studied. A fuller understanding of the role of large landslides in landscape evolution requires addressing this gap, since the distribution of large landslides may affect broad regions through interactions with channel processes, and since the dominant controls on landslide distribution might be expected to vary with tectonic setting. We documented >400 landslides between 0.1 and ~40 km2 across ~140,000 km2 of eastern Oregon, in the semiarid, southern interior Columbia River basin. The mapped landslides cluster in a NW-SE-trending band that is 50-100 km wide. Landslides predominantly occur where even modest local relief (~100 m) exists near key contacts between weak sedimentary or volcaniclastic rock and coherent cap rock. Fault density exerts no control on landslide distribution, while ~10% of mapped landslides cluster within 3-10 km of mapped fold axes. Landslide occurrence is curtailed to the NE by thick packages of coherent basalt and to the SW by limited local relief. Our results suggest that future mass movements will localize in areas stratigraphically preconditioned for landsliding by a geologic history of fluviolacustrine and volcaniclastic sedimentation and episodic capping by coherent lava flows. In such areas, episodic landsliding may persist for hundreds of thousands of years or more, producing valley wall slopes of ~7??-13?? and impacting local channels with an evolving array of mass movement styles. ?? 2011 Geological Society of America.

  18. High-pressure metamorphism in the southern New England Orogen: Implications for long-lived accretionary orogenesis in eastern Australia

    NASA Astrophysics Data System (ADS)

    Phillips, G.; Offler, R.; Rubatto, D.; Phillips, D.

    2015-09-01

    New geochemical, metamorphic, and isotopic data are presented from high-pressure metamorphic rocks in the southern New England Orogen (eastern Australia). Conventional and optimal thermobarometry are augmented by U-Pb zircon and 40Ar/39Ar phengite dating to define pressure-temperature-time (P-T-t) histories for the rocks. The P-T-t histories are compared with competing geodynamic models for the Tasmanides, which can be summarized as (i) a retreating orogen model, the Tasmanides formed above a continuous, west dipping, and eastward retreating subduction zone, and (ii) a punctuated orogen model, the Tasmanides formed by several arc accretion, subduction flip, and/or transference events. Whereas both scenarios are potentially supported by the new data, an overlap between the timing of metamorphic recrystallization and key stages of Tasmanides evolution favors a relationship between a single, long-lived subduction zone and the formation, exhumation, and exposure of the high-pressure rocks. By comparison with the retreating orogen model, the following links with the P-T-t histories emerge: (i) exhumation and underplating of oceanic eclogite during the Delamerian Orogeny, (ii) recrystallization of underplated and exhuming high-pressure rocks at amphibolite facies conditions coeval with a period of rollback, and (iii) selective recrystallization of high-pressure rocks at blueschist facies conditions, reflecting metamorphism in a cooled subduction zone. The retreating orogen model can also account for the anomalous location of the Cambrian-Ordovician high-pressure rocks in the Devonian-Carboniferous New England Orogen, where sequential rollback cycles detached and translated parts of the leading edge of the overriding plate to the next, younger orogenic cycle.

  19. Occurrence of organophosphorus flame retardants in indoor dust in multiple microenvironments of southern China and implications for human exposure.

    PubMed

    He, Chun-Tao; Zheng, Jing; Qiao, Lin; Chen, She-Jun; Yang, Jun-Zhi; Yuan, Jian-Gang; Yang, Zhong-Yi; Mai, Bi-Xian

    2015-08-01

    Organophosphorus flame retardants (OPFRs) are important alternatives to brominated flame retardants (BFRs), but information on their contamination of the environment in China is rare. We examined the occurrence of 12 OPFRs in indoor dust in four microenvironments of southern China, including a rural electronic waste (e-waste) recycling area, a rural non-e-waste area, urban homes, and urban college dormitory rooms. The OPFR concentrations (with a median of 25.0 μg g(-1)) were highest in the e-waste area, and the concentrations in other three areas were lower and comparable (7.48-11.0 μg g(-1)). The levels of OPFRs in the present study were generally relatively lower than the levels of OPFRs found in Europe, Canada, and Japan because BFRs are still widely used as the major FRs in China. The composition profile of OPFRs in the e-waste area was dominated by tricresyl phosphate (TCP) (accounting for 40.7%, on average), while tris(2-chloroethyl) phosphate (TCEP) was the most abundant OPFR (64.4%) in the urban areas (homes and college dormitories). These two distribution patterns represent two OPFR sources (i.e., emissions from past e-waste and from current household products and building materials). The difference in the OPFR profiles in the rural area relative to the OPFR profiles in the urban and e-waste areas suggests that the occurrence of OPFRs is due mainly to emissions from characteristic household products in rural homes. Although human exposures to all the OPFRs were under the reference doses, the health risk for residents in the e-waste area is a concern, considering the poor sanitary conditions in this area and exposure from other sources. PMID:25898308

  20. Hillslope response to knickpoint migration in the Southern Appalachians: Implications for the evolution of post-orogenic landscapes

    USGS Publications Warehouse

    Wegmann, S.F.G.; Franke, K.L.; Hughes, S.; Lewis, R.Q.; Lyons, N.; Paris, P.; Ross, K.; Bauer, J.B.; Witt, A.C.

    2011-01-01

    The southern Appalachians represent a landscape characterized by locally high topographic relief, steep slopes, and frequent mass movement in the absence of significant tectonic forcing for at least the last 200 Ma. The fundamental processes responsible for landscape evolution in a post-orogenic landscape remain enigmatic. The non-glaciated Cullasaja River basin of south-western North Carolina, with uniform lithology, frequent debris flows, and the availability of high-resolution airborne lidar DEMs, is an ideal natural setting to study landscape evolution in a post-orogenic landscape through the lens of hillslope-channel coupling. This investigation is limited to channels with upslope contributing areas >2.7 km2, a conservative estimate of the transition from fluvial to debris-flow dominated channel processes. Values of normalized hypsometry, hypsometric integral, and mean slope vs elevation are used for 14 tributary basins and the Cullasaja basin as a whole to characterize landscape evolution following upstream knickpoint migration. Results highlight the existence of a transient spatial relationship between knickpoints present along the fluvial network of the Cullasaja basin and adjacent hillslopes. Metrics of topography (relief, slope gradient) and hillslope activity (landslide frequency) exhibit significant downstream increases below the current position of major knickpoints. The transient effect of knickpoint-driven channel incision on basin hillslopes is captured by measuring the relief, mean slope steepness, and mass movement frequency of tributary basins and comparing these results with the distance from major knickpoints along the Cullasaja River. A conceptual model of area-elevation and slope distributions is presented that may be representative of post-orogenic landscape evolution in analogous geologic settings. Importantly, the model explains how knickpoint migration and channel- hillslope coupling is an important factor in tectonically-inactive (i

  1. Diagenetic Patterns of the Cretaceous Baseline Sandstone, Southern Nevada: Implications for Controls on Iron-Oxide Cementation and Coloration

    NASA Astrophysics Data System (ADS)

    Duncan, C. J.; Chan, M. A.

    2015-12-01

    The Cretaceous Baseline Sandstone of the Sevier foreland basin deposits in southern Nevada exhibits intense diagenetic iron-oxide coloration and bleaching, and contains abundant cemented masses. The Baseline Formation is ~1 km thick with three alluvial to fluvial members: the basal White (Kbw) Member, overlain by coeval Red (Kbr) and Overton Conglomerate (Kbo) Members. Iron-oxide diagenetic features occur in two broad classes: 1) bedding parallel coloration facies of diffuse to banded red, pink, purple, white, to yellow colors; and 2) concretionary facies of heavily cemented horizons, pods/lenses, spherical to spheroidal concretions, boxworks, pipes, and irregular concretion forms. A distinctive geometry is the occurrence of large (~1 m diameter) spherical "beach ball" concretions within the Kbr. Preliminary mapping of diagenetic features shows that concretionary facies are more common within a ~125 m interval near the bottom of Kbw, and within the lower ~125 m of Kbr. Intense coloration changes are present throughout Kbw but occur only in the lowermost ~150 m of Kbr. In the Kbw, concretionary forms commonly occur in stratigraphic intervals of fine-grained sandstone, siltstone, and mudstone lithologies, whereas cemented masses are much less common in stratigraphic intervals composed of medium-grained sandstone and conglomerate lithologies. Additionally, both Kbw and Kbr Members exhibit rare examples of wood fragments in the center of iron-oxide concretions, suggesting the importance of organics as nucleation sites for precipitation. The distribution of complex and overprinted diagenetic patterns indicates nested scales of processes involving iron-oxide dissolution, mobilization, and precipitation. Overall stratigraphic architecture influenced formation-scale patterns, but specific lithologies and textures influenced the type and distribution of diagenetic facies at outcrop scales, and organic content encouraged cementation at grain-scales.

  2. Analysis of coastal sea-level station records and implications for tsunami monitoring in the Adriatic Apulia region, southern Italy

    NASA Astrophysics Data System (ADS)

    Bressan, Lidia; Tinti, Stefano; Tallarico, Andrea

    2015-04-01

    The region of Apulia, southern Italy, was theater of one of the largest tsunami disaster in Italian history (the 30 July 1627 event) and is considered to be exposed to tsunami hazard coming from local Italian sources as well as from sources on the eastern side of the Adriatic and from the Ionian sea, including the Hellenic Arc earthquakes. Scientific interest for tsunami studies and monitoring in the region is only recent and this theme was specifically addressed by the international project OTRIONS, coordinated by the University of Bari. In the frame of this project the University of Bologna contributed to the analysis of the tsunami hazard and to the evaluation of the regional tide-gauge network with the scope of assessing its adequacy for tsunami monitoring. This latter is the main topic of the present work. In eastern Apulia, facing the Adriatic sea, the sea-level data network is sufficiently dense being formed of stations of the Italian tide-gauge network (Rete Mareografica Nazionale, RMN), of four additional stations operated by the Apulia Port Authority (in Brindisi, Ischitella, Manfredonia and Porto Cesareo) and of two more stations that were installed in the harbours of Barletta and Monopoli in the frame of the project OTRIONS with real-time data transmission and 1-sec sampling period. Pre-processing of the sea-level data of these stations included quality check and spectral analysis. Where the sampling rate was adequate, the records were also examined by means of the specific tools provided by the TEDA package. This is a Tsunami Early Detection Algorithm, developed by the Tsunami Research Team of the University of Bologna, that allows one to characterize the sea-level background signal in the typical tsunami frequency window (from 1 to several minutes) and consequently to optimize TEDA parameters for an efficient tsunami detection. The results of the analysis show stability of the spectral content and seasonal variations.

  3. Compositional diversity of Late Cenozoic basalts in a transect across the southern Washington Cascades: Implications for subduction zone magmatism

    SciTech Connect

    Leeman, W.P. ); Smith, D.R. ); Hildreth, W. ); Palacz, Z.; Rogers, N. )

    1990-11-10

    Major volcanoes of the Southern Washington Cascades (SWC) include the large quaternary stratovolcanoes of Mount St. Helens (MSH) and Mount Adams (MA) and the Indian Heaven (IH) and Simcoe Mountain (SIM) volcanic fields. There are significant differences among these volcanic centers in terms of their composition and evolutionary history. The authors conclude that subducted fluids and sediments do not play an essential role in producing these magmas. Rather, they infer that they formed by variable degree melting of a mixed mantle source consisting mainly of heterogeneously distributed OIB and mid-ocean ridge basalt source domains. Relatively minor occurrences of high field strength element (HFSE) depleted arclike basalts may reflect the presence of a small proportion of slab-metasomatized subarc mantle. The juxtaposition of such different mantle domains within the lithospheric mantle is viewed as a consequence of (1) tectonic mixing associated with accretion of oceanic and island arc terranes along the Pacific margin of North America prior to Neogene time, and possibly (2) a seaward jump in the locus of subduction at about 40 Ma. The Cascades arc is unusual in that the subducting oceanic plate is very young and hot. They suggest that slab dehydration outboard of the volcanic front resulted in a diminished role of aqueous fluids in generating or subsequently modifying SWC magmas compared to the situation at most convergent margins. Furthermore, with low fluid flux conditions, basalt generation is presumably triggered by other processes that increase the temperature of the mantle wedge (e.g., convective mantle flow, shear heating, etc.).

  4. Quaternary morphotectonic mapping of the Wadi Araba and implications for the tectonic activity of the southern Dead Sea fault

    NASA Astrophysics Data System (ADS)

    Le BéOn, Maryline; Klinger, Yann; MéRiaux, Anne-Sophie; Al-Qaryouti, Mahmoud; Finkel, Robert C.; Mayyas, Omar; Tapponnier, Paul

    2012-10-01

    The Dead Sea strike-slip fault accommodates the northward motion of Arabia relative to Sinai at a rate of ˜5 mm/yr. The southern segment of the fault, the Wadi Araba fault, runs along a valley blanketed in Quaternary sediments. We first focused on understanding the relative and absolute timing of emplacement of the alluvial surfaces. We then determined the probable source of the sediments before assessing their lateral offset to constrain the late Pleistocene fault slip rate. Seven successive morphostratigraphic levels were identified. At two sites, we recognized an alluvial sequence of five to seven successive levels with ages getting younger northward, a pattern consistent with the western block moving southward relative to two fixed feeding channels located to the east. Surface samples were collected for10Be cosmogenic radionuclide dating. Fans F3 and F5 were found to be synchronous from site to site, at 102 ± 26 ka and 324 ± 22 ka, respectively, while F4 could be dated at 163 ± 19 ka at one site only. These are minimum ages, assuming no erosion of the alluvial surfaces. At least two of these periods are correlated with wet periods that are regionally well documented. Further analyses of tectonic offsets are affected in most cases by large uncertainties due to the configuration of the sites. They indicate maximum offsets of ˜5.5 km for the oldest, possibly ˜1 Ma old, surfaces. They lead to bracketing of the fault slip rate between 5 and 12 mm/yr, with preferred values of 5-7 mm/yr, for the last 300 ka.

  5. Eocene-Pliocene stratigraphy along the southern margin of the Wind River Range, Wyoming: revisions and implications from field and fission-track studies

    SciTech Connect

    Steidtmann, J.R.; Middleton, L.T.

    1986-01-01

    The established mid-Tertiary stratigraphy along the southern margin of the Wind River Range is of questionable chronologic validity because of the difficulty in discriminating among the several tuffaceous units and because lithologic criteria have been used as chronostratigraphic indicators. Field observations and zircon fission-track ages suggest certain revisions of, and additions to, this stratigraphy. These include: (1) recognition of the Cathedral Bluffs Tongue of the Wasatch Formation at Reds Cabin monocline, (2) establishment of a late Oligocene or early Miocene age for the South Pass Formation and (3) recognition that there are middle Miocene deposits previously mapped as Arikaree that consist of reworked Arikaree shed off the upthrown side of the Continental fault. The implications of these findings are that the Continental fault, now a collapse feature, was a tear fault during the early Eocene, that there are most likely Oligocene rocks north of the Continental fault, that there was late Oligocene or early Miocene uplift in the core of the Wind River Range and that the range collapsed in the middle Miocene.

  6. Modified Gulf of California model for South Georgia,north Scotia Ridge, and implications for the Rocas Verdes back-arc basin, southern Andes

    NASA Astrophysics Data System (ADS)

    Alabaster, T.; Storey, B. C.

    1990-06-01

    New field mapping and an integrated trace element and Nd isotopic study have been undertaken on the Jurassic-Cretaceous Larsen Harbour Complex on the island of South Georgia, recognized as a displaced part of the southern Andes ensialic, autochthonous Rocas Verdes marginal basin. Five basalt groups (Groups I-V) are identified from trace element data; initial Nd isotopic compositions suggest that they are derived from only two sources. Magmas produced during early stages of continental lithospheric attenuation (Groups I-III) were derived by varying degrees of partial melting and fractional crystallization from a large ion lithophile element (LILE)-enriched, low-ɛNd mantle source relative to normal (N)-type mid-ocean ridge basalt (MORB). Magmas produced during later stages of rifting (Groups IV and V) were, however, derived from a high-ɛNd asthenospheric mantle source similar to N-type MORB, unaffected by earlier LILE enrichment. Our data do not concur with previous suggestions that the Larsen Harbour Complex and, by implication, the Rocas Verdes formed in a supra-subduction-zone setting. On the basis of geologic and geochemical evidence, we favor basin formation along an oblique-slip margin akin to that of the Gulf of California.

  7. Modified gulf of California model for South Georgia, north Scotia Ridge, and implications for the Rocas Verdes back-arc basin, southern Andes

    SciTech Connect

    Alabaster, T.; Storey, B.C. )

    1990-06-01

    New field mapping and an integrated trace element and Nd isotopic study have been undertaken on the Jurassic-Cretaceous Larsen Harbour Complex on the island of South Georgia, recognized as a displaced part of the southern Andes ensialic, autochthonous Rocas Verdes marginal basin. Five basalt groups (Groups I-V) are identified from trace element data; initial Nd isotopic compositions suggest that they are derived from only two sources. Magmas produced during early stages of continental lithospheric attenuation (Groups I-III) were derived by varying degrees of partial melting and fractional crystallization from a large ion lithophile element (LILE)-enriched, low-{epsilon}{sub Nd} mantle source relative to normal (N)-type mid-ocean ridge basalt (MORB). Magmas produced during later stages of rifting (Groups IV and V) were, however, derived from a high-{epsilon}{sub Nd} asthenospheric mantle source similar to N-type MORB, unaffected by earlier LILE enrichment. Our data do not occur with previous suggestions that the Larsen Harbour Complex and, by implication, the Rocas Verdes formed in a supra-subduction-zone setting. On the basis of geologic and geochemical evidence, we favor basin formation along an oblique-slip margin akin to that of the Gulf of California.

  8. Multi-scale structural and kinematic analysis of a Neoarchean shear zone in northeastern Minnesota: Implications for assembly of the southern Superior Province

    NASA Astrophysics Data System (ADS)

    Dyess, Jonathan

    This dissertation is a multi-scale structural and kinematic analysis of the Shagawa Lake shear zone in northeastern Minnesota (USA). The Neoarchean Shagawa Lake shear zone is an ~70 km long ~7 km wide subvertical package of L-S tectonites located within the Wawa Subprovince of the Archean Superior Province. In this dissertation, I (1) discuss a new method for mapping regional tectonic fabrics using high-resolution LiDAR altimetry data; (2) examine the geometric relationships between metamorphic foliation, elongation lineation, vorticity, and non-coaxial shear direction within individual L-S tectonites; and (3) incorporate LiDAR, field, and microstructural data sets into a comprehensive structural and kinematic analysis of the Western Shagawa Lake shear zone. Lastly, I discuss implications for assembly of the southern Superior Province. In Chapter one I examine an Archean granite-greenstone terrane in NE Minnesota to illustrate the application of high-resolution LiDAR altimetry to mapping regional tectonic fabrics in forested, glaciated areas. I describe the recognition of lineaments and distinguishing between tectonic and glacial lineament fabrics. I use a 1-m posted LiDAR derived bare-earth digital elevation model (DEM) to construct multiple shaded-relief images for lineament mapping with sun elevation of 45˚ and varying sun azimuth in 45˚ intervals. Two suites of lineaments are apparent. Suite A has a unimodal orientation, mean trend of 035, and consists of short (> 2 km long) lineaments within sediment deposits and bedrock. Suite B lineaments, which are longer (1-30 km) than those of suite A, have a quasi-bimodal orientation distribution, with maximum trends of 065 and 090. Only one lineament suite is visible in areas where suites A and B are parallel. I interpret suite A as a surficial geomorphologic fabric related to recent glaciation, and suite B as a proxy for the regional tectonic fabric. In Chapter two I present a detailed kinematic study of seven

  9. Character and Implications of a Newly Identified Creeping Strand of the San Andreas fault NE of Salton Sea, Southern California

    NASA Astrophysics Data System (ADS)

    Janecke, S. U.; Markowski, D.

    2015-12-01

    The overdue earthquake on the Coachella section, San Andreas fault (SAF), the model ShakeOut earthquake, and the conflict between cross-fault models involving the Extra fault array and mapped shortening in the Durmid Hill area motivate new analyses at the southern SAF tip. Geologic mapping, LiDAR, seismic reflection, magnetic and gravity datasets, and aerial photography confirm the existence of the East Shoreline strand (ESS) of the SAF southwest of the main trace of the SAF. We mapped the 15 km long ESS, in a band northeast side of the Salton Sea. Other data suggest that the ESS continues N to the latitude of the Mecca Hills, and is >35 km long. The ESS cuts and folds upper Holocene beds and appears to creep, based on discovery of large NW-striking cracks in modern beach deposits. The two traces of the SAF are parallel and ~0.5 to ~2.5 km apart. Groups of east, SE, and ENE-striking strike-slip cross-faults connect the master dextral faults of the SAF. There are few sinistral-normal faults that could be part of the Extra fault array. The 1-km wide ESS contains short, discontinuous traces of NW-striking dextral-oblique faults. These en-echelon faults bound steeply dipping Pleistocene beds, cut out section, parallel tight NW-trending folds, and produced growth folds. Beds commonly dip toward the ESS on both sides, in accord with persistent NE-SW shortening across the ESS. The dispersed fault-fold structural style of the ESS is due to decollements in faulted mud-rich Pliocene to Holocene sediment and ramps and flats along the strike-slip faults. A sheared ladder-like geometric model of the two master dextral strands of the SAF and their intervening cross-faults, best explains the field relationships and geophysical datasets. Contraction across >40 km2 of the southernmost SAF zone in the Durmid Hills suggest that interaction of active structures in the SAF zone may inhibit the nucleation of large earthquakes in this region. The ESS may cross the northern Coachella

  10. Average Stress Drops of Southern California Earthquakes in the Context of Crustal Geophysics: Implications for Fault Zone Healing

    NASA Astrophysics Data System (ADS)

    Hauksson, Egill

    2015-05-01

    To understand how fault healing processes affect earthquake stress drops, we search for a possible dependency of stress drops on crustal conditions and geophysical parameters. We reanalyze the stress drop values of ~60,000 earthquakes in southern California which were originally determined by Shearer et al. J Geophys Res 111:B06303, (2006) using a spectral method. We modify the dataset to include only stress drops that are derived from at least 10 spectra and with corner frequencies between 3 and 30 Hz, and correct the rupture velocity for increasing S-wave speed with depth. We see no dependence of stress drop on moment magnitude or depth, except for a small, poorly determined increase from 15 to 25 km. We use six crustal geophysics parameters to search for obvious correlations that may explain changes in the mean values of the stress drops: (1) crustal thickness, (2) isostatic gravity, (3) heat flow, (4) shear strain rate, (5) crustal stress regime, and (6) style of faulting. None of the variables reduce the scatter but most can explain up to 10-20 % variations in the mean stress drops. The geographical distribution of the grouped mean stress drops includes very high stress drops near Ridgecrest, eastern California, as well as near fault jogs within the San Andreas Fault system. Low stress drops dominate in trans-tensional regions. Heat flow and GPS-based shear strain rate estimates have the largest influence on stress drop variations. In the range of low to medium heat flow, the stress drops increase with increasing heat flow. In contrast, at high heat flow in thin crust, the stress drops decrease systematically with increasing heat flow. Increasing shear strain rate systematically correlates with decreasing stress drops. The crustal stress regime and style of faulting also influence the stress drops as demonstrated by lower stress drops for north-northeast trending principal horizontal stress and in areas of dip-slip faulting. The mean variations in stress drops

  11. Origin of the Lyme Dome and implications for the timing of multiple Alleghanian deformational and intrusive events in southern Connecticut

    USGS Publications Warehouse

    Walsh, G.J.; Aleinikoff, J.N.; Wintsch, R.P.

    2007-01-01

    Geologic mapping, structural analysis, and geochronology in the area of the Lyme dome, southern Connecticut provides constraints on the origin of the rocks in the core of the dome, the absolute timing of the principal deformational and thermal events attributed to Alleghanian orogenesis, and the processes that generated the dome. Detrital zircon geochronology in combination with ages on intrusive rocks brackets the deposition of quartzite in the core of the dome sometime between ca. 925 and 620 Ma. Granite and granodiorite intruded the Neoproteorozic metasedimentary rocks in the core of the dome at ca. 620 to 610 Ma. Four major early Permian events associated with the Alleghanian orogeny affected the rocks in the Lyme dome area. Syn-tectonic migmatization and widespread penetrative deformation (D1, ca. 300 - 290 Ma) included emplacement of alaskite at 290 ?? 4 Ma during regional foliation development and aluminosilicate-orthoclase metamorphic conditions. Rocks of the Avalon terrane may have wedged between Gander cover rocks and Gander basement in the core of the Lyme during D1. Limited structural evidence for diapiric uplift of the Lyme dome indicates that diapirism started late in D1 and was completed by D2 (ca. 290 - 280 Ma) when horizontal WNW contractional stresses dominated over vertical stresses. Second sillimanite metamorphism continued and syn-tectonic D2 granite pegmatite (288 ?? 4 Ma) and the Joshua Rock Granite Gniess (284 ?? 3 Ma) intruded at this time. North-northwest extension during D3 (ca. 280 - 275 Ma) led to granitic pegmatite intrusion along S3 cleavage planes and in extensional zones in boudin necks during hydraulic failure and decompression melting. Intrusion of a Westerly Granite dike at 275 ?? 4 Ma suggests that D3 extension was active, and perhaps concluding, by ca. 275 Ma. Late randomly oriented but gently dipping pegmatite dikes record a final stage of intrusion during D4 (ca. 275 - 260 Ma), and a switch from NNW extension to vertical

  12. Volcanic risk and tourism in southern Iceland: Implications for hazard, risk and emergency response education and training

    NASA Astrophysics Data System (ADS)

    Bird, Deanne K.; Gisladottir, Gudrun; Dominey-Howes, Dale

    2010-01-01

    This paper examines the relationship between volcanic risk and the tourism sector in southern Iceland and the complex challenge emergency management officials face in developing effective volcanic risk mitigation strategies. An early warning system and emergency response procedures were developed for communities surrounding Katla, the volcano underlying the Mýrdalsjökull ice cap. However, prior to and during the 2007 tourist season these mitigation efforts were not effectively communicated to stakeholders located in the tourist destination of Þórsmörk despite its location within the hazard zone of Katla. The hazard zone represents the potential extent of a catastrophic jökulhlaup (glacial outburst flood). Furthermore, volcanic risk mitigation efforts in Þórsmörk were based solely on information derived from physical investigations of volcanic hazards. They did not consider the human dimension of risk. In order to address this gap and provide support to current risk mitigation efforts, questionnaire surveys were used to investigate tourists' and tourism employees' hazard knowledge, risk perception, adoption of personal preparedness measures, predicted behaviour if faced with a Katla eruption and views on education. Results indicate that tourists lack hazard knowledge and they do not adopt preparedness measures to deal with the consequences of an eruption. Despite a high level of risk perception, tourism employees lack knowledge about the early warning system and emergency response procedures. Results show that tourists are positive about receiving information concerning Katla and its hazards and therefore, the reticence of tourism employees with respect to disseminating hazard information is unjustified. In order to improve the tourism sector's collective capacity to positively respond during a future eruption, recommendations are made to ensure adequate dissemination of hazard, risk and emergency response information. Most importantly education campaigns

  13. Spinel + quartz assemblage in granulites from the Achankovil Shear Zone, southern India: Implications for ultrahigh-temperature metamorphism

    NASA Astrophysics Data System (ADS)

    Shimizu, Hisako; Tsunogae, Toshiaki; Santosh, M.

    2009-09-01

    We report the finding of equilibrium spinel + quartz assemblage enclosed within garnet in garnet-orthopyroxene-cordierite granulites from Pakkandom within the Achankovil Shear Zone, a region which is considered as the trace of an accretionary suture in recent tectonic models on southern India. The spinel + quartz bearing granulites are composed of poikiloblastic garnet and subidioblastic orthopyroxene in the matrix of quartz, plagioclase, biotite, cordierite, and Fe-Ti oxides. Garnet contains numerous inclusions of sillimanite and biotite as well as spinel and quartz. The spinel in direct contact with quartz has moderate XMg (= Mg/(Fe 2+ + Mg) = 0.44-0.47), and is Zn and Fe 3+ poor ( XZn = Zn/(Fe 2+ + Mg + Zn) = 0.027-0.036, Fe 3+/(Fe 2+ + Fe 3+) = 0.12-0.17). Spinel is also present in the matrix surrounded by magnetite, but the matrix spinel contains more Zn( XZn = 0.067-0.072) and does not show any contact relationship with quartz. Such Zn- and Fe 3+-poor spinel in direct contact with quartz has been regarded as a diagnostic evidence of ultrahigh-temperature (UHT) metamorphism. The high-temperature stability of the spinel + quartz is also supported by the results of geothermobarometric calculation of garnet-orthopyroxene assemblages that provides robust evidence for peak UHT metamorphism at 920-980 °C and 8-10 kbar, which was further confirmed by Al-in-Opx and magnetite-ilmenite geothermometers (900-950 °C and ˜1000 °C, respectively). The peak UHT event was followed by decompression down to 4.0-4.2 kbar and 640-670 °C toward the stability of cordierite along a clockwise P-T path. Similar spinel + quartz assemblage enclosed in poikiloblastic garnet has also been reported from the Palghat-Cauvery Shear Zone system, the trace of a major suture zone within the Gondwana amalgam with evidence for prograde high-pressure ( P up to 20 kbar) metamorphism followed by UHT event. The fine-grained spinel + quartz may thus indicate decompression from higher pressure

  14. Constraining the age of Liuqu Conglomerate, southern Tibet: Implications for tectonic evolution of the Indus-Yarlung Suture Zone

    NASA Astrophysics Data System (ADS)

    Li, G.; Sandiford, M.; Kohn, B.

    2014-12-01

    , F.Y., and Jansa, L., 2010, Provenance of the Liuqu Conglomerate in southern Tibet: A Paleogene erosional record of the Himalayan-Tibetan orogen: Sedimentary Geology, v. 231, p. 74-84, doi:10.1016/j.sedgeo.2010.09.004.

  15. Geophysical exploration of an active pockmark field in the Bay of Concarneau, southern Brittany, and implications for resident suspension feeders

    NASA Astrophysics Data System (ADS)

    Baltzer, Agnès; Ehrhold, Axel; Rigolet, Carinne; Souron, Aurélie; Cordier, Céline; Clouet, Hélène; Dubois, Stanislas F.

    2014-06-01

    About a decade ago, a large field of pockmarks (individual features up to 30 m in diameter and <2 m deep) was discovered in water depths of 15-40 m in the Bay of Concarneau in southern Brittany along the French Atlantic coast, covering an overall area of 36 km2 and characterised by unusually high pockmark densities in places reaching 2,500 per square kilometre. As revealed by geophysical swath and subbottom profile data ground-truthed by sediment cores collected during two campaigns in 2005 and 2009, the confines of the pockmark field show a spectacular spatial association with those of a vast expanse of tube mats formed by a benthic community of the suspension-feeding amphipod Haploops nirae. The present study complements those findings with subbottom chirp profiles, seabed sonar imagery and ultrasonic backscatter data from the water column acquired in April 2011. Results show that pockmark distribution is influenced by the thickness of Holocene deposits covering an Oligocene palaeo-valley system. Two groups of pockmarks were identified: (1) a group of large (>10 m diameter), more widely scattered pockmarks deeply rooted (up to 8 ms two-way travel time, TWTT) in the Holocene palaeo-valley infills, and (2) a group of smaller, more densely spaced pockmarks shallowly rooted (up to 2 ms TWTT) in interfluve deposits. Pockmark pore water analyses revealed high methane concentrations peaking at ca. 400 μl/l at 22 and 30 cm core depth in silty sediments immediately above Haploops-bearing layers. Water column data indicate acoustic plumes above pockmarks, implying ongoing pockmark activity. Pockmark gas and/or fluid expulsion resulting in increased turbidity (resuspension of, amongst others, freshly settled phytoplankton) could at least partly account for the strong spatial association with the phytoplankton-feeding H. nirae in the Bay of Concarneau, exacerbating impacts of anthropogenically induced eutrophication and growing offshore trawling activities. Tidally driven

  16. A magnetostratigraphic study of the sediments of the Ridge Basin, southern California and its tectonic and sedimentologic implications

    NASA Astrophysics Data System (ADS)

    Ensley, Ross A.; Verosub, Kenneth L.

    1982-06-01

    A magnetic polarity zonation has been established for the upper Castaic Formation and lower Ridge Route and Peace Valley Formations of the Ridge Basin of the central Transverse Ranges of southern California. The zonation is based on the analysis of over 1900 samples from 669 sites in the 5800 m thick sedimentary sequence. Rock magnetic studies provide evidence that the carrier of the primary remanence is magnetite and that the magnetization was acquired at or shortly after deposition of the sediment. Although many samples contain a secondary, normal overprint, systematic analysis of the changes in direction upon demagnetization leads to an accurate determination of the original polarity. Thirteen polarity intervals are recognized. On the basis of biostratigraphic constraints imposed by a marine invertebrate faunaat the base of the sequence and a terrestrial vertebrate fauna at the top, the magnetic polarity zonation can be correlated to the magnetic polarity time scale. The studied interval extends from the Epoch 5/Epoch 6 boundary to the middle of Epoch 8. Polarity changes within the studied interval represent chronostratigraphic horizons which can be used to analyze tectonic and sedimentologic processes which are recorded in the sediments of the Ridge Basin. The locus of the tectonic activity within the basin has been dated as occurring on the Clearwater fault from 8.1 to 7.8 m.y. ago, on the Liebre faultfrom 7.3 to 6.1 m.y. ago and on the North Liebre fault from 6.0 to 5.0 m.y. ago. During this entire period of time, the San Gabriel fault on the western margin of the basin was continuously active, and a period of particularly vigorous activity has been dated at 7.3 to 7.0 m.y. The mean declinations of samples from the normal magnetozones provide no evidence for the existence of a major rotation of the Ridge Basin subsequent to about 8.5 m.y. ago. Sedimentation rates for interbedded sandstone and shale units within the basin have been separately determined as 0

  17. A temporary pond in the Early Cretaceous of southern England: palaeoclimatic implications of nonmarine "Purbeck-Wealden" ostracod faunas

    NASA Astrophysics Data System (ADS)

    Horne, D. J.

    2009-04-01

    Group in southern England. Special Papers in Palaeontology, 68, 1-18, 2 pls. Nye, E., Feist-Burkhardt, S., Horne, D. J., Ross, A. J. & Whittaker, J. E. (2008) The palaeoenvironment associated with a partial Iguanodon skeleton from the Upper Weald Clay (Barremian, Early Cretaceous) at Smokejacks Brickworks (Ockley, Surrey, UK), based on palynomorphs and ostracods. Cretaceous Research, 29, 417-444.

  18. Superficial Cancer in the Sudan. A Study of 1225 Primary Malignant Superficial Tumours

    PubMed Central

    Malik, M. O. A.; Hidaytalla, A.; Daoud, E. H.; el Hassan, A. M.

    1974-01-01

    Superficial cancer in the Sudan accounted for 17·2% of all malignant tumours examined histologically during the period 1962-72 inclusive. Of the 4 pathological types studied, squamous cell carcinoma was the commonest (63·3% of all superficial cancers) followed by malignant melanoma (18·8%) and basal cell carcinoma (14·9%) whilst Kaposi's sarcoma formed only 3% of the total. Generally, twice as many cases occurred in males as in females, with the exception of Kaposi's sarcoma where all the patients were males. Although a relatively high proportion of cases occurred in the young age groups, the age-specific incidence was noted to increase with age. Similarities and differences in the anatomical site of tumours compared with European and African series were noted. Certain differences emerged in the geographical distribution of these tumours in the Northern and Southern regions of the Sudan—regions which differ both ethnologically and geographically—thus suggesting possible roles played by racial and environmental factors in this respect. PMID:4447778

  19. Radiocarbon dating and paleoclimatic significance of subfossil Limicolaria in northwestern Sudan

    NASA Astrophysics Data System (ADS)

    Haynes, C. Vance; Mead, Albert R.

    1987-07-01

    The discovery, identification, and radiocarbon dating of the large achatinid land snail Limicolaria kambeul chudeaui at six places in northwestern Sudan, north of the 100-mm isohyet, provide convincing evidence that at least 300 mm annual rainfall existed there 6000 yr ago. Since then the rainfall north of ca. 20°N lat in the eastern Sahara has certainly been <300 mm and probably <200 mm. Accelerator mass spectrometry has allowed the organic fraction, presumably conchiolin, to be accurately radiocarbon dated whereas carbonate fractions are ca. 600 yr too old. Comparative studies show the subfossil form, L. k. chudeaui, to be the most primitive in its species complex and to occupy a narrow east-west belt across Africa north of 15°N and west of 35°E. The northern limit of living forms lies within the southern part of the Sahelian zone in forest or forest-savanna. They cannot live in open grassland. Therefore, the distribution of L. k. chudeaui marks the former northern position of this zone during the middle Holocene, indicating a latitudinal shift of at least 5° (500 km).

  20. Tectono-thermal History of the Southern Nenana Basin, Interior Alaska: Implications for Conventional and Unconventional Hydrocarbon Exploration

    NASA Astrophysics Data System (ADS)

    Dixit, N. C.; Hanks, C. L.

    2014-12-01

    The Tertiary Nenana basin of Interior Alaska is currently the focus of both new oil exploration and coalbed methane exploitation and is being evaluated as a potential CO2sequestration site. The basin first formed as a Late Paleocene extensional rift with the deposition of oil and gas-prone, coal-bearing non-marine sediments with excellent source potential. Basin inversion during the Early Eocene-Early Oligocene times resulted in folding and erosion of higher stratigraphic levels, forming excellent structural and stratigraphic traps. Initiation of active faulting on its eastern margin in the middle Oligocene caused slow tectonic subsidence that resulted in the deposition of reservoir and seal rocks of the Usibelli Group. Onset of rapid tectonic subsidence in Pliocene that continues to the present-day has provided significant pressure and temperature gradient for the source rocks. Apatite fission-track and vitrinite reflectance data reveals two major paleo-thermal episodes: Late Paleocene to Early Eocene (60 Ma to 54.8 Ma) and Late Miocene to present-day (7 Ma to present). These episodes of maximum paleotemperatures have implications for the evolution of source rock maturity within the basin. In this study, we are also investigating the potential for coalbed methane production from the Late Paleocene coals via injection of CO2. Our preliminary analyses demonstrate that 150 MMSCF of methane could be produced while 33000 tonnes of CO2 per injection well (base case of ~9 years) can be sequestered in the vicinity of existing infrastructure. However, these volumes of sequestered CO2and coal bed methane recovery are estimates and are sensitive to the reservoir's geomechanical and flow properties. Keywords: extensional rift, seismic, subsidence, thermal history, fission track, vitrinite reflectance, coal bed methane, Nenana basin, CO2 sequestration

  1. Minerals and trace elements in silcretes of the Sado basin (Alentejo, southern Portugal) and implications for silcrete formation

    NASA Astrophysics Data System (ADS)

    Sauer, Daniela; Kullmann, Sarah; Zarei, Mehdi; Stahr, Karl

    2014-05-01

    Soils in the eastern part of the Sado basin (southern Portugal) are often characterized by massive cementations caused by silica. The thickness and massive character of these silcretes led to the hypothesis that accumulation of silica took place not only vertically within a soil profile, but also by enrichment through lateral water and element flow into the Sado basin. The aims of the study reported here were: 1) to characterize the cementing agent with regard to its mineralogy; 2) to test the hypothesis that silification was enhanced through lateral silica transport from the adjacent Alto Alentejo into the Sado basin. Aim 1) was achieved by scratching silica coatings from ped surfaces of the silicified soil horizons and cleaning them manually in the lab under a binocular microscope. After careful smashing with a mortar, density separation by sodium polytungstate solution was applied to remove any remaining mineral grains from the silica samples. The cleaned silica samples were then subjected to XRD and SEM in combination with EDS. Aim 2) was attained by using trace element contents of predominant rock types of the Alto Alentejo and of the silcretes in the Sado basin for identifying lateral pathways of water and silica in the landscape. Ten rock samples from the assumed source area of silica were combusted by fusion melt, and their contents of Ba, Co, Cs, Nb, Pb, Rb, Sr, Y and Zr were analyzed by ICP-MS. The same elements were analyzed in NaOH extracts of the cemented soil horizons in the Sado basin. The X-ray diagrams of the silica coatings show the expected broad hump of amorphous silica. In addition, quartz, kaolinite, and surprisingly high amounts of halloysite are identified, the latter reflecting conditions of intensive weathering and pedogenesis during the formation of the silica coatings. This intensive soil formation and hence silification most likely took place during Pliocene. Greater age is impossible, because the silification took place in Pliocene

  2. Compositional diversity of Late Cenozoic basalts in a transect across the southern Washington Cascades: Implications for subduction zone magmatism

    NASA Astrophysics Data System (ADS)

    Leeman, William P.; Smith, Diane R.; Hildreth, Wes; Palacz, Zen; Rogers, Nick

    1990-11-01

    Major volcanoes of the Southern Washington Cascades (SWC) include the large Quaternary stratovolcanoes of Mount St. Helens (MSH) and Mount Adams (MA) and the Indian Heaven (IH) and Simcoe Mountain (SIM) volcanic fields. There are significant differences among these volcanic centers in terms of their composition and evolutionary history. The stratovolcanoes consist largely of andesitic to dacitic lavas and pyroclastics with minor basalt flows. IH consists dominantly of basaltic with minor andesite lavas, all erupted from monogenetic rift and cinder cone vents. SIM has a poorly exposed andesite to rhyolite core but mainly consists of basaltic lavas erupted from numerous widely dispersed vents; it has the morphology of a shield volcano. Distribution of mafic lavas across the SWC is related to north-northwest trending faults and fissure zones that indicate a significant component of east-west extension within the area. There is overlap in eruptive history for the areas studied, but it appears that peak activity was progressively older (MSH (<40 Ka), IH (mostly <0.5 Ma), MA (<0.5 Ma), SIM (1-4 Ma)) and more alkalic toward the east. A variety of compositionally distinct mafic magma types has been identified in the SWC, including low large ion lithophile element (LILE) tholeiitic basalts, moderate LILE calcalkalic basalts, basalts transitional between these two, LILE-enriched mildly alkalic basalts, and basaltic andesites. Compositional diversity among basaltic lavas, both within individual centers as well as across the arc, is an important characteristic of the SWC traverse. The fact that the basaltic magmas either show no correlation between isotopic and trace element components or show trends quite distinct from those of the associated evolved lavas, suggests that their compositional variability is attributable to subcrustal processes. Both the primitive nature of the erupted basalts and the fact that they are relatively common in the SWC sector also imply that such

  3. Paleoclimatic implications (Late Cretaceous-Paleogene) from micromorphology of calcretes, palustrine limestones and silcretes, southern Paraná Basin, Uruguay

    NASA Astrophysics Data System (ADS)

    Tófalo, Ofelia R.; Pazos, Pablo J.

    2010-04-01

    Sedimentologic and petrographic analyses of outcroping and subsurface calcretes, palustrine carbonates, and silcretes were carried out in the southern Paraná Basin (Uruguay). The aim of this work is to describe the microfabric and interpret the genesis of these rocks through detailed analyses, since they contain significant paleoenvironmental and paleoclimatic evolution information. The main calcrete and silcrete host rock (Mercedes Formation) is represented by a fluvial thinning upward succession of conglomerate and sandstone deposits, with isolated pelitic intervals and paleosoils. Most of the studied calcretes are macroscopically massive with micromorphological features of alpha fabric, originated by displacive growth of calcite in the host clastic material due to evaporation, evapotranspiration and degassing. Micromorphologically, calcretes indicate an origin in the vadose and phreatic diagenetic environments. Micrite is the principal component, and speaks of rapid precipitation in the vadose zone from supersaturated solutions. The abundance of microsparite and secondary sparite is regarded as the result of dissolution and reprecipitation processes. Although present, brecciated calcretes are less common. They are frequent in vadose diagenetic environments, where the alternation between cementation and non-tectonic fracturing conditions take place. These processes generated episodes of fragmentation, brecciation and cementation. Fissures are filled with clear primary sparitic calcite, formed by precipitation of extremely supersaturated solutions in a phreatic diagenetic environment. The micromorphological characteristics indicate that calcretes resulted from carbonate precipitation in the upper part of the groundwater table and the vadose zone, continuously nourished by lateral migration of groundwater. The scarcity of biogenic structures suggests that they were either formed in zones of little biological activity or that the overimposed processes related to

  4. Cooling History in Mabja Dome, Southern Tibet: Implications for the Tectonic Evolution of the North Himalayan Gneiss Domes

    NASA Astrophysics Data System (ADS)

    Lee, J.; Wang, Y.; McWilliams, M.; Hourigan, J.; Blythe, A.; McClelland, W.

    2001-12-01

    The Mabja Dome (MD), southern Tibet, is one of a series of gneiss domes, called the North Himalayan Gneiss Domes, located south of the Indus-Tsangpo suture zone and north of the high Himalaya. The MD consists of an ~25 km diameter doubly plunging antiform cored by migmatitic K-feldspar augen biotite orthogneiss which is mantled by high grade metapelites and granitic orthogneisses. These rocks record two primary deformational events: an older deformational event, D1, characterized by ~EW-trending folds of S0 with an associated moderately N-dipping axial planar foliation, S1, and a younger event, D2, characterized by a domed mylonitic foliation, S2, and associated NS-trending mineral stretching lineation. Peak metamorphism is pre- to early syntectonic with D2 structures and defines a set of isograds that are subparallel to structure. Two-mica granites, one of which yielded an U/Pb monazite age of 14.5+/-0.1 Ma, were emplaced during the latest stages of D2 deformation. Mica and kspar Ar/Ar and apatite fission track (AFT) analyses were completed on orthogneisses, metasediments, and two-mica granites to shed light on the timing and mechanism of cooling of these rocks. Muscovite yielded Ar/Ar cooling ages of ~12.7 Ma on the northern flank of the dome, increasing to ~17.0 Ma in metapelite and orthogneiss at deeper structural levels, and decreasing to ~13.5 Ma within migmatite at the deepest structural levels. Biotites are disturbed and yield total gas ages that are slightly younger than muscovite on the flanks of the dome, but older within the core. Analyses of four kspars from orthogneiss and migmatite yielded complex spectra with old apparent ages at the lowest temperature steps, followed by ages that climb slowly from 12.5-13.0 Ma over the first 30% of 39Ar released, which in turn is followed by ages that climb to 100 Ma (orthogneiss) and 15-18 Ma (migmatite) at high temperature steps. AFT analyses from orthogneiss and migmatite yielded a mean age of 9.5 Ma indicating

  5. Paleomagnetism of the Ocotillo Badlands, southern California, and implications for slip transfer through an antidilational fault jog

    NASA Astrophysics Data System (ADS)

    Brown, Norman N.; Fuller, Michael D.; Sibson, Richard H.

    1991-03-01

    of the Ocotillo Formation, shortly after the time of the field reversal. If total slip on the Coyote Creek fault at the Ocotillo Badlands is greater than 800 m, it appears that the fault jog has been a transitory feature within the fault zone, with slip alternately bypassing it or being transferred across it. Such switchyard behavior of slip transfer through the fault jog has important implications for understanding structural controls on earthquake rupture.

  6. Large Glacitectonic structures on the Dogger Bank, southern North Sea; Implications for glacial dynamics, glacial limits, and interplay between the British and Fennoscandinavian Ice Sheets

    NASA Astrophysics Data System (ADS)

    Dove, Dayton; Cotterill, Carol; Long, Dave; Ruiter, Astrid; Phillips, Emrys; James, Leo; Forsberg, Carl Fredrik

    2013-04-01

    caused by sub-glacial (gravitational spreading), ice-marginal (push-moraine complex), or pro-glacial (ice-push) processes, or a combination of the three at an oscillating ice-margin. The thrusts appear to have no surface expression, suggesting the topography was removed either by late-stage glacial erosion or Holocene marine transgression. Work to date on the paleoenvironmental implications of the data has been preliminary. The exact style, pattern, and timing glacial deformation (and associated sedimentation) on the Dogger Bank and circum-southern North Sea, and glacial history of the region, will be the focus of a Ph.D studentship which commenced Sept. 2012.

  7. Oil exploration in nonmarine rift basins of interior Sudan

    SciTech Connect

    Schull, T.J.

    1984-04-01

    In early 1975 Chevron Overseas Petroleum Inc. commenced a major petroleum exploration effort in previously unexplored interior Sudan. With the complete cooperation of the Sudanese Government, Chevron has acquired a vast amount of geologic and geophysical data during the past 9 years. These data include extensive aeromagnetic and gravity surveys, 25,000 mi (40,200 km) of seismic data, and the results of 66 wells. This information has defined several large rift basins which are now recognized as a major part of the Central African rift system. The sedimentary basins of interior Sudan are characterized by thick Cretaceous and Tertiary nonmarine clastic sequences. Over 35,000 ft (10,600 m) of sediment have been deposited in the deepest trough, and extensive basinal areas are underlain by more than 20,000 ft (6100 m) of sediment. The depositional sequence includes thick lacustrine shales and claystones, flood plain claystones, and lacustrine, fluvial, and alluvial sandstones and conglomerates. Those lacustrine claystones which were deposited in an anoxic environment provide oil-prone source rocks. Reservoir sandstones have been found in a wide variety of nonmarine sandstone facies. The extensional tectonism which formed these basins began in the Early Cretaceous. Movement along major fault trends continued intermittently into the Miocene. This deformation resulted in a complex structural history which led to the formation of several deep fault-bounded troughs, major interbasin high trends, and complex basin flanks. This tectonism has created a wide variety of structures, many of which have become effective hydrocarbon traps.

  8. Seasonal variation and hypertensive disorders of pregnancy in eastern Sudan.

    PubMed

    Ali, A A; Adam, G K; Abdallah, T M

    2015-02-01

    The aim of this study was to investigate the seasonal variation and hypertensive disorders of pregnancy in eastern Sudan, in the period between January 2008 and December 2010. The medical files of women attending at Kassala hospital, eastern Sudan with hypertension, with or without proteinuria were retrospectively retrieved. The data of patients with hypertensive disorders of pregnancy were compared with a similar number of controls that were normotensive and non-proteinuric. During the study period, there were 9,578 deliveries; 153 patients had hypertensive disorders of pregnancy, yielding an incidence rate of 1.6%. Of all cases and controls (306), there were 183 (59.8%) deliveries in winter, 84 (27.5%) in summer and 39 (12.7%) in autumn. The highest rate of pre-eclampsia was in winter (1.1%) (CI = 1.1-2.7, OR = 1.7, p = 0.004) and the lowest rate was in autumn (0.2%) (CI = 0.4-1.8, OR = 0.8, p = 0.758.). Our study revealed significant association between the incidence of hypertensive disorders of pregnancy and the winter season (103 (67.3%) vs 80 (52.3%), p = 0.001). Thus, more attention in the winter season might reduce the morbidity and mortality of hypertensive disorders of pregnancy. PMID:25141293

  9. Sudan General Petroleum Corporation: a study of the evolution of its organization

    SciTech Connect

    Ali, A.E.

    1984-01-01

    This study is of an exploratory nature, with the purpose of investigating the evolution of the organization, macro and micro, of Sudan General Petroleum Corporation (SGPC) and how it relates to government strategy toward the petroleum sector. The study addresses the following questions: what changes took place in the organization of SGPC for the period 1900-1983. What changes took place in the government strategy toward the petroleum industry for the corresponding period. How did the changes in SGPC organization relate to the changes in government strategy. What generalizations can be made about the relationship between government strategy toward the petroleum industry and the structure of state petroleum enterprises in developing countries. What are the implications for the future organizational structure of SGPC and its relationships to external entities. The study shows that the organization of SGPC, macro and micro, tends to change in response to the changes in government strategy toward the petroleum sector. Certain political and economic factors shaped the government strategy, which in turn influenced the structure of SGPC. The SGPC organization, in its most complex form in 1983, is the result of the concatenation of several basic strategies.

  10. Staining histological lung sections with Sudan Black B or Sudan III for automated identification of alveolar epithelial type II cells.

    PubMed

    Schneider, Jan Philipp; Pedersen, Lars; Mühlfeld, Christian; Ochs, Matthias

    2015-10-01

    Alveolar epithelial type II (AE2) cells produce, store and secrete pulmonary surfactant and serve as progenitor cells for the alveolar epithelium. They are thus an interesting target in wide fields of pulmonary research. Stereological methods allow their quantification based on measurements on histological sections. A proper AE2 cell quantification, however, requires a method of tissue processing that results in little tissue shrinkage during processing. It was recently shown that a primary fixation with a mixture of glutaraldehyde and formaldehyde, postfixation with osmium tetroxide and uranyl acetate and embedding in glycol methacrylate fulfills this requirement. However, a proper quantification, furthermore, requires a secure identification of the cells under the microscope. Classical approaches using routine stainings, high magnifications and systematic uniform random sampling can result in a tedious counting procedure. In this article we show that Sudan Black B and Sudan III staining in combination with the previously described "low shrinkage method" of tissue processing result in good staining of lamellar bodies of AE2 cells (their storing organelles of surfactant) and thus provide a good signal of AE2 cells, which allows their easy and secure identification even at rather low magnifications. We further show that this signal enables automated detection of AE2 cells by image analysis, which should make this method a suitable staining method for the recently developed and more efficient proportionator sampling. PMID:26558990

  11. New insights into the origin of the subduction component in Late Oligocene magmatism in the Ronda peridotite (southern Spain): geodynamic implications for the western Mediterranean

    NASA Astrophysics Data System (ADS)

    Varas-Reus, María Isabel; Garrido, Carlos J.; Marchesi, Claudio; Bosch, Delphine; Hidas, Károly; Acosta-Vigil, Antonio

    2013-04-01

    Oligocene subduction-related magmatism in the Ronda peridotite, and its implications for geodynamic models of the western Mediterranean in the Cenozoic. REFERENCES Garrido, C. J., F. Gueydan, G. Booth-Rea, J. Precigout, K. Hidas, J. A. Padrón-Navarta, and Marchesi C. . (2011) Garnet lherzolite and garnet-spinel mylonite in the Ronda peridotite: Vestiges of Oligocene backarc mantle lithospheric extension in the western Mediterranean, Geology, 39(10), 927-930. Hidas, K., Booth-Rea, G, Garrido, C. J., Martínez-Martínez, J. M., Padrón-Navarta, J. A., Konc, Z., Giaconia, F., Frets, E., and Marchesi, C. (2013) . Backarc basin inversion and subcontinental mantle emplacement in the crust: kilometre-scale folding and shearing at the base of the proto-Alborán lithospheric mantle (Betic Cordillera, southern Spain): Journal of the Geological Society, London. Marchesi, C., Garrido, C. J., Bosch, D., Bodinier, J.-L., Hidas, K., Padrón-Navarta, J. A., and Gervilla, F. (2012) A Late Oligocene Suprasubduction Setting in the Westernmost Mediterranean Revealed by Intrusive Pyroxenite Dikes in the Ronda Peridotite (Southern Spain): The Journal of Geology, 120 (2), 237-247.

  12. Mapping Extensional Structures in the Makgadikgadi Pans, Botswana with remote sensing and aeromagnetic data: Implication for the continuation of the East African Rift System in southern Africa

    NASA Astrophysics Data System (ADS)

    Fetkovich, E. J.; Atekwana, E. A.; Abdelsalam, M. G.; Atekwana, E. A.; Katumwehe, A. B.

    2015-12-01

    We used Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM) and aeromagnetic data to map extensional structures in the Makgadikgadi Pans in northeastern Botswana. These pans are a major morphological feature in Southern Africa characterized by the presence of low lying and flat topography with the highest elevation of 945 m. This topography was a result of multiple filling and desiccation of paleo-lakes that accompanied alternation of wetter and dryer climate during the Late Quaternary period. The objective of our study was to map the extent and distribution of normal faults using their morphological expression and magnetic signature, and examine their relationship with paleo-shorelines of the pans. We: (1) Created a hill shade relief map from the SRTM DEM; (2) Extracted regional NW-SE trending topographic profiles across the pans; (3) Constructed displacement profiles for major normal faults; and (4) Created tilt derivative images from the aeromagnetic data. We found that: (1) The northeastern part of the pan is dissected by three morphologically-defined NE-trending normal faults. The along strike continuity of these faults is in the range of 75 and 170 km and they are spaced at ~30 km apart from each other. (2) The topographic profiles suggest that the exposed minimum vertical displacement (EMVD), defined by poorly developed escarpments, is in the range of 0 m and 49 m. (3) The displacement profiles of the faults is characterized by maximum EMVD in the middle of the faults and that it decays towards the fault tips. These faults are also apparent in the aeromagnetic maps where they seem to displace E-W trending Karoo-age dikes. (4) At least the outer paleo-shoreline of the pans is modified by the NE-trending faults. This suggests that the faults are younger than the paleo-shorelines, which is suggested to have been developed between 500 and 100 ka. Traditionally, the southwestern extension of the East African Rift System has been assigned to the

  13. Reinvestigating the Mission Creek Fault: Holocene slip rates in the northern Coachella Valley and implications for southern California earthquake hazard assessment

    NASA Astrophysics Data System (ADS)

    Wersan, Louis Samuel

    Coachella Valley. Constraining active slip on the Mission Creek fault has significant implications for southern California fault modeling and earthquake hazard assessment, and allows quantification of maximum strain transfer in the Coachella Valley from the Mission Creek fault to the Eastern California Shear Zone (˜9 mm/yr).

  14. Investigation of natural radioactivity levels in water around Kadugli, Sudan.

    PubMed

    Osman, Alfatih A A; Salih, Isam; Shaddad, Ibrahim A; El Din, Saif; Siddeeg, M B; Eltayeb, Hatem; Idriss, Hajo; Hamza, Walid; Yousif, E H

    2008-11-01

    Surface water from Miri Lake and groundwater from around Kadugli (West-Central Sudan) obtained by means of hand-pumps was analysed for (238)U, (226)Ra, (222)Rn, and (232)Th activity concentrations. The surface water showed very low levels of radionuclide concentrations: <1.0-7.5, 8.5-16.5, <1.6, and <0.1-0.39 mBq L(-1) for (238)U, (226)Ra, (222)Rn, and (232)Th, respectively. Groundwater revealed a significant amount of natural radioactivity (16.1-1720, 7.7-14.3, 3000-139,000, <0.1-39 mBq L(-1)) respectively. The overall annual effective dose was below the WHO reference dose level of 0.1 mSv yr(-1) except in one groundwater sample with an associated dose of 0.7 mSv yr(-1). PMID:18513978

  15. Characterization of a new cucurbit-infecting ipomovirus from Sudan.

    PubMed

    Desbiez, Cécile; Verdin, Eric; Tepfer, Mark; Wipf-Scheibel, Catherine; Millot, Pauline; Dafalla, Gasim; Lecoq, Hervé

    2016-10-01

    Two members of the genus Ipomovirus (family Potyviridae) are known to infect cucurbits: cucumber vein yellowing virus (CVYV), which is emerging throughout the Mediterranean Basin, and squash vein yellowing virus (SqVYV), which has been described in America and the Caribbean Basin, and more recently in Israel. In this work, an ipomovirus different from CVYV and SqVYV, tentatively named coccinia mottle virus (CocMoV), was detected in a sample of the cucurbit Coccinia grandis collected in central Sudan in 2012. Sequence identity in nt was 68 % with CVYV, 59-60 % with SqVYV, cassava brown streak virus and Ugandan cassava brown streak virus, and less than 50 % with other members of the family Potyviridae. Preliminary biological and epidemiological studies indicate that CocMoV has a narrow natural host range and a low prevalence. PMID:27430562

  16. The Impact of Conflict on Forests in South Sudan

    NASA Astrophysics Data System (ADS)

    Gorsevski, V.; Kasischke, E. S.; Dempewolf, J.; Loboda, T. V.; Geores, M.

    2014-12-01

    The impacts of armed conflict on ecosystems are complex and difficult to assess due to restricted access to affected areas making satellite remote sensing a useful tool for studying direct and indirect effects of conflict on the landscape. The Imatong Central Forest Reserve (ICFR) in South Sudan together with the nearby Dongotana Hills and the Agoro-Agu Forest Reserve (AFR) in Northern Uganda share a boundary and encompass a biologically diverse montane ecosystem. This study used satellite data combined with general human population trends to examine the impact of armed conflict and its outcome on similar forest ecosystems both during and after hostilities. A Disturbance Index (DI) was used to investigate the location and extent of forest cover loss and gain in three areas for two key time periods. Results indicate that the rate of forest recovery was significantly higher than the rate of disturbance both during and after wartime in and around the ICFR. In contrast, the nearby Dongotana Hills experienced relatively high rates of disturbance during both periods; however, post war period losses were largely offset by some gains in forest cover. Discussions with local inhabitants confirmed these findings and provided further insights into the underlying causes impacting forest cover and wildlife. South Sudan is the latest nation to join the Global Environment Facility (GEF). While the GEF does not explicitly address conflict, many of the projects it supports occur in conflict and post-conflict zones with wide-ranging repercussions for both people and the environment. In an effort to assess best practices for working in conflict and post-conflict areas, the GEF Scientific and Technical Advisory Panel (STAP) will undertake an analysis of GEF-funded projects over the last two decades to identify where the GEF has promoted cooperation between groups and states, and/or made a positive contribution toward conflict avoidance resulting in shared environmental benefits.

  17. International Aid as Informal Educator: Exploring Political Attitudes and Engagement in Southern Sudan

    ERIC Educational Resources Information Center

    Pagen, Christine Mary

    2010-01-01

    Scholarship has isolated internal economic conditions and political institutions as essential factors in political development and democracy-building, this research suggests that external influences are at play. During times of civil war and post-conflict reconstruction, governmental and socioeconomic structures are likely weak or nonexistent, and…

  18. Education in Emergencies and Early Reconstruction: UNICEF Interventions in Colombia, Liberia, and Southern Sudan

    ERIC Educational Resources Information Center

    Beleli, Ozsel; Chang, Victoria; Feigelson, Michael J.; Kopel-Bailey, Jules A.; Maak, Sheila A.; Mnookin, Jacob P.; Nguyen, Thu H.; Salazar, Mariana; Sinderbrand, Joy E.; Tafoya, Simon N.

    2007-01-01

    Broad access to quality, child-friendly education in emergencies is a critical component of early reconstruction and development. As a class of graduate students at the Woodrow Wilson School of Public and International Affairs at Princeton University, our goal is to make a modest contribution to the field of education in emergencies by working…

  19. 78 FR 68500 - In the Matter of the Designation of Jama'atu Ansarul Muslimina Fi Biladis-Sudan Also Known as...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... as Ansarul Muslimina Fi Biladis Sudan Also Known as Vanguards for the Protection of Muslims in Black... known as Ansarul Muslimina Fi Biladis Sudan, also known as Vanguards for the Protection of Muslims...

  20. Guayape-Papalutla fault system: A continuous Cretaceous structure from southern Mexico to the Chortís block? Tectonic implications

    NASA Astrophysics Data System (ADS)

    Silva-Romo, G.

    2008-01-01

    Recent papers have opened the debate over whether the Chortísblock was located off the coast of southern Mexico or in a moreoutboard position, and this led me to explore whether correlationswith older structures could be established to determine theevolution of the southwest corner of the North America plate.In this paper I hypothesize that the Papalutla fault of Mexicoand the Guayape fault system of Honduras, both considered tobe terrane boundaries, were roughly continuous in the Cretaceous,extending from southern Mexico to the Chortís block.They influenced Early Cretaceous clastic sedimentation of theZicapa Formation on the Guerrero-Morelos Platform (southernMexico) and the Tepemechin Formation of the Central Chortísterrane (Honduras). The units accumulated in fault-bounded basinsassociated with left-lateral slip. The basins developed in theCentral Chortís terrane and Guerrero-Morelos Platform.Both geological entities appear to represent a continuous Cretaceousgeologic province characterized by a trangression that occurredearlier in Honduras than in southern Mexico. This nonrotationalhypothesis for the location of the Chortís block adjacentto southern Mexico during the Cretaceous is consistent withnortheastward displacement of the Caribbean plate during Cretaceoustime and implies 1500 km of Chortís block displacementduring the Cenozoic.

  1. Hydrological, socio-economic and reservoir alterations of Er Roseires Dam in Sudan.

    PubMed

    Alrajoula, Mohammad Taher; Al Zayed, Islam Sabry; Elagib, Nadir Ahmed; Hamdi, Moshrik R

    2016-10-01

    Er Roseires Dam plays a key role in controlling the Blue Nile flow in Sudan. This study explores the influence of the dam on the hydrological regimes, which in turn have implications for the ecosystem. The Range of Variability Approach (RVA) - based on a set of 32 indicators - was applied over the period 1965 to 2014 to establish a safe range of river flow. Moreover, remotely-sensed data of the Normalized Difference Vegetation Index (NDVI) was used to analyse the spatio-temporal variation of the dam's reservoir area over the period 2000-2014. Significant influence on the dry-season hydrological indicators is expressed by high negative hydrological alteration of the range from -47% to -100%, but the dam contributes positively through flow regulation during the flood season. Impounding water procedure and fluctuation of water flow caused by the dam are found to induce significant alterations. Releasing less water during the dry season and more gradual impounding process, which are not expected to affect the power generation or irrigation practices, are recommended for better ecological restoration. The total surface area of the reservoir has changed post the implementation of the dam heightening project. Since 2012, the lake surface area has expanded by 250%. Relationships between the lake size and the head have been developed to help in the monitoring of the hydrological conditions and, accordingly, in managing the dam operation. A field survey showed that the dam plays a positive social role as the reservoir supports local activities, such as fishery, farming, and collection of wood and fruits. But increased humidity and health problems have also been noted. The Grand Ethiopian Renaissance Dam (GERD) would have a direct effect on Er Roseires Dam and the river flow downstream. High level of coordination among the riparian countries is recommended for better river water management. PMID:27288976

  2. Extraction of Sudan dyes from environmental water by hemimicelles-based magnetic titanium dioxide nanoparticles.

    PubMed

    Li, Chenyu; Chen, Ligang; You, Xiaoxiao

    2014-11-01

    A novel method for the extraction of Sudan dyes including Sudan I, II, III, and IV from environmental water by magnetic titanium dioxide nanoparticles (Fe3O4@TiO2) coated with sodium dodecylsulfate (SDS) as adsorbent was reported. Fe3O4@TiO2 was synthesized by a simple method and was characterized by transmission electron microscopy, Fourier-transform infrared spectrometry, and vibrating sample magnetometer. The magnetic separation was quite efficient for the adsorption and desorption of Sudan dyes. The effect of the amount of SDS, extraction time, pH, desorption condition, maximal extraction volume, and humic acid on the extraction process were investigated. This method was employed to analyze three environmental water samples. The results demonstrated that our proposed method had wide linear range (25-5,000 ng L(-1)) with a good linearity (R (2) > 0.999) and low detection limits (2.9-7.3 ng L(-1)). An enrichment factor of 1,000 was achieved. In all three spiked levels (25, 250, and 2,500 ng L(-1)), the recoveries of Sudan dyes were in the range of 86.9-93.6 %. The relative standard deviations obtained were ranging from 2.5 to 9.3 %. That is to say, the new method was fast and effective for the extraction of Sudan dye from environmental water. PMID:24938811

  3. Development of an enzyme-linked immunosorbent assay specific to Sudan red I.

    PubMed

    Xu, Ting; Wei, Ke Yi; Wang, Jia; Eremin, Sergei A; Liu, Shang Zhong; Li, Qing X; Li, Ji

    2010-10-01

    To obtain antibodies to develop an enzyme-linked immunosorbent assay (ELISA) for the analysis of Sudan red I, haptens were designed and synthesized via four different strategies: (i) attachment of a spacer at the para position of the benzene ring, (ii) attachment of a spacer at the naphthol part, (iii) attachment of a spacer at the hydroxyl group of the Sudan red I molecule, and (iv) use of a fragment of the target molecule. A total of 10 haptens were used to generate immunogens, coating antigens, and polyclonal antibodies. One of the heterologous ELISAs developed exhibited an IC(50) of 1.6 ng/ml, a limit of detection (LOD) of 0.03 ng/ml, and a dynamic range between 0.1 and 14 ng/ml. The assay had 13% cross-reactivity with Para red and negligible cross-reactivity with other structure-related compounds. This ELISA was much more specific than those published previously. This assay was used to determine Sudan red I residues in tomato sauce and chili powder samples after simple pretreatment. The results were validated by comparison with high-performance liquid chromatography (HPLC). The average recoveries of Sudan red I by ELISA and HPLC were in ranges of 70-97% and 82-114%, respectively, indicating suitability of the developed ELISA for screening of Sudan red I in foods. PMID:20522332

  4. The Relationship between Leadership Style and Motivation among Faculty Members in Two Public Universities in the Republic of South Sudan

    ERIC Educational Resources Information Center

    Malok, Malok N.

    2012-01-01

    The purpose of this study was to investigate the relationship between leadership style and motivation among faculty members in two public universities in the Republic of the South Sudan. The researcher examined this issue by surveying and interviewing faculty members in two public universities in the Republic of South Sudan, a total of 67 for…

  5. 76 FR 63635 - Extension of the Designation of Sudan for Temporary Protected Status and Automatic Extension of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ... extraordinary and temporary conditions within that country. See 62 FR 59737; section 244(a)(b)(1)(A), (C) of the... redesignated Sudan for TPS a total of 12 times, including this extension. See 74 FR 69355 (Dec. 31, 2009.... 69 FR 60168 (Oct. 7, 2004). The last extension of TPS for Sudan was announced on December 31,...

  6. Modelling of sedimentation processes inside Roseires Reservoir (Sudan)

    NASA Astrophysics Data System (ADS)

    Omer, A. Y. A.; Ali, Y. S. A.; Roelvink, J. A.; Dastgheib, A.; Paron, P.; Crosato, A.

    2015-04-01

    Roseires Reservoir, located on the Blue Nile River in Sudan, is the first trap to the sediments coming from the vast upper river catchment in Ethiopia, which suffers from high erosion and desertification problems. The reservoir has already lost more than one-third of its storage capacity due to sedimentation in the last four decades. Appropriate management of the eroded soils in the upper basin could mitigate this problem. In order to do that, the areas providing the highest sediment volumes to the river have to be identified, since they should have priority with respect to the application of erosion control practices. This requires studying the sedimentation record inside Roseires Reservoir in order to assess when and how much sediment is deposited and to identify its source. This paper deals with the identification of deposition time and soil stratification inside the reservoir, based on historical bathymetric data, numerical modelling and newly acquired soil data. The remoteness of the study area and the extreme climate result in coring campaigns being expensive and difficult. Therefore, these activities need to be optimised and coring locations selected beforehand. This was done by combining bathymetric data and the results of a depth-averaged morphodynamic model recording the vertical stratification in sediment deposits. The model allowed for recognising the areas that are potentially subject to neither net erosion nor bar migration during the lifespan of the reservoir. Verification of these results was carried out by analysing sediment stratification from the data collected during the subsequent field campaign.

  7. Rift basins of interior Sudan: petroleum exploration and discovery

    SciTech Connect

    Schull, T.J.

    1988-10-01

    The sedimentary basins of interior Sudan are characterized by thick nonmarine clastic sequences of Jurassic(.)-Cretaceous and Tertiary age. Over 45,000 ft (13,716 m) of sediment was deposited in the deepest trough and extensive basinal areas are underlain by more than 20,000 ft (6096 m) of sedimentary rocks. The depositional sequences include thick lacustrine shales and claystones, flood plain claystones, and lacustrine, fluvial, and alluvial sandstones and conglomerates. Those lacustrine claystones deposited in a suboxic environment provide good oil-prone source rocks. Reservoir sandstones have been found in a wide variety of nonmarine sandstone facies. The extensional tectonism that formed these basins began in the Jurassic(.)-Early Cretaceous. Movement along major fault trends continued intermittently into the Miocene. This deformation resulted in a complex structural history that led to the formation of several deep fault-bounded troughs, major interbasinal highs, and complex basin flanks. This tectonism has created a wide variety of structures, many of which have become effective hydrocarbon traps. During the past eight years, several important oil discoveries have been made. Significant accumulations have been delineated in the Heglig and Unity areas, where estimated recoverable reserves are 250-300 million bbl of oil. 14 figures.

  8. Economic development and the allocation of petroleum products in Sudan

    SciTech Connect

    Cain, M. ); Yousif, M.A.R. )

    1991-01-01

    The Sudanese economy has been characterized in recent years by severe energy shortages which have affected all economic activity. More than 94% of the commercial energy is imported and the level of such imports is seriously limited by the current foreign exchange crisis. However, the problem is not just one of foreign exchange; there is also the problem of utilization of resources to avoid bottleneck problems of supply. The allocation of petroleum products in Sudan has had a severe effect on all aspects of economic life. The aim of this paper is to highlight the problem and to build a model to optimize the distribution of petroleum products in order to achieve at least a minimal supply in all regions. A large linear programming model has been developed and the solution indicates that current facilities should be able to satisfy 96% of the 1986 demand, about 30% more than the actual supply. Furthermore, with a little investment in storage facilities and extra trucks, the supply could satisfy total demand in the immediate future.

  9. Epidemiology of Substance Use among University Students in Sudan.

    PubMed

    Osman, Tarig; Victor, Cathrine; Abdulmoneim, Alaa; Mohammed, Hala; Abdalla, Fatima; Ahmed, Asma; Ali, Eiman; Mohammed, Wael

    2016-01-01

    Background. Youth populations are vulnerable to substance use particularly in developing countries where circumstances may be favorable for it. There is no published data on substance use among the youth in Sudan other than on tobacco use. Objectives. The aim of this study was to investigate the prevalence, circumstances, and factors associated with substance use. Methods. An institution-based survey was conducted on a sample of 500 students. Data was collected using a questionnaire designed by the WHO for student drug surveys and analyzed using IBM SPSS version 20. Results. The overall prevalence of substance use is 31%. The current prevalence of tobacco, cannabis, alcohol, amphetamines, tranquilizers, inhalants, opiates, cocaine, and heroin use was 13.7%, 4.9%, 2.7%, 2.4%, 3.2%, 1%, 1.2%, 0.7%, and 0.5%, respectively. Curiosity (33.1%) was the main reason for initiation of substance use. The main adverse effects reported were health problems (19.7%) and theft (19.7%). Peers (40.9%) were the prime source of substance use. On multivariate analysis, male sex was the principle predictor for substance use (AOR: 5.55; 95% CI: 3.38, 9.17). Conclusion. Strategies to control substance use should encompass the role of the university and parents in observing and providing education to improve awareness of substances and their consequences. PMID:27006856

  10. Ocular disorders among schoolchildren in Khartoum State, Sudan.

    PubMed

    Rushood, A A; Azmat, S; Shariq, M; Khamis, A; Lakho, K A; Jadoon, M Z; Sial, N; Rushood, A A; Kamil, E A

    2013-03-01

    From December 2005 to June 2007, a total screening of all 1418 government primary schools in Khartoum State, Sudan, was performed to estimate ocular problems among children aged 6-15 years. We screened 671,119 children (56.7% males) for significant refractive error and other eye ailments. Ocular problems were found in 20,321 (3.03%) children. The 3 localities with highest ocular pathology were Karary (26.2%), Ummbada (21.0%) and Jabal Awlia (15.7%). The overall prevalence of refractive error was 2.19%. Myopia was found in 10,064 (1.50%) children while 4661 (0.70%) were hyperopic. Other ocular problems included vernal keratoconjunctivitis, vitamin A deficiency, microbial conjunctivitis, strabismus and corneal opacity. Only 288 (0.04%) children were diagnosed with active trachoma: 86.5% of these were from Ummbada locality, on the periphery ofthe State, where transportation facilities are poor and poverty is widespread. Overall, 99% of the eye ailments identified are either treatable or preventable. To reduce these and to achieve the goals of Vision 2020, an effective and efficient school health programme is needed. PMID:23879081

  11. Agricultural pesticide exposure and perinatal mortality in central Sudan.

    PubMed Central

    Taha, T. E.; Gray, R. H.

    1993-01-01

    Hospital- and community-based studies were conducted in central Sudan to investigate the association between pesticide exposure and perinatal mortality. The cases were 197 stillbirths in the hospital and 36 perinatal deaths in the community; the controls were 812 liveborn, normal-birth-weight infants in the hospital, and 1505 liveborn infants who survived for the first 7 days after birth in the community. The odds ratio (OR) of perinatal death associated with pesticide exposure was estimated using multiple logistic regression. There was a consistent and significant association between pesticide exposure and perinatal mortality in the hospital (adjusted OR = 1.9; 95% confidence interval (CI): 1.3-2.8) and the community populations (adjusted OR = 2.7; 95% CI: 1.1-6.4). The OR was significantly higher among women engaged in farming (3.6; 95% CI: 1.6-8.0), but not among women in nonfarming occupations (1.6; 95% CI: 0.8-3.3). The estimated attributable risks of perinatal death owing to pesticide exposure were 22.6% for hospital stillbirths and 15.7% for community perinatal deaths; but among women engaged in farming in the hospital population the attributable risks were substantially higher (34.5%). PMID:8324850

  12. Epidemiology of Substance Use among University Students in Sudan

    PubMed Central

    Osman, Tarig; Victor, Cathrine; Abdulmoneim, Alaa; Mohammed, Hala; Abdalla, Fatima; Ahmed, Asma; Ali, Eiman; Mohammed, Wael

    2016-01-01

    Background. Youth populations are vulnerable to substance use particularly in developing countries where circumstances may be favorable for it. There is no published data on substance use among the youth in Sudan other than on tobacco use. Objectives. The aim of this study was to investigate the prevalence, circumstances, and factors associated with substance use. Methods. An institution-based survey was conducted on a sample of 500 students. Data was collected using a questionnaire designed by the WHO for student drug surveys and analyzed using IBM SPSS version 20. Results. The overall prevalence of substance use is 31%. The current prevalence of tobacco, cannabis, alcohol, amphetamines, tranquilizers, inhalants, opiates, cocaine, and heroin use was 13.7%, 4.9%, 2.7%, 2.4%, 3.2%, 1%, 1.2%, 0.7%, and 0.5%, respectively. Curiosity (33.1%) was the main reason for initiation of substance use. The main adverse effects reported were health problems (19.7%) and theft (19.7%). Peers (40.9%) were the prime source of substance use. On multivariate analysis, male sex was the principle predictor for substance use (AOR: 5.55; 95% CI: 3.38, 9.17). Conclusion. Strategies to control substance use should encompass the role of the university and parents in observing and providing education to improve awareness of substances and their consequences. PMID:27006856

  13. Ethical, legal and social aspects of the approach in Sudan

    PubMed Central

    El Sayed, Badria B; Malcolm, Colin A; Babiker, Ahmed; Malik, Elfatih M; El Tayeb, Mohammed AH; Saeed, Nageeb S; Nugud, Abdel Hameed D; Knols, Bart GJ

    2009-01-01

    The global malaria situation, especially in Africa, and the problems frequently encountered in chemical control of vectors such as insecticide resistance, emphasize the urgency of research, development and implementation of new vector control technologies that are applicable at regional and local levels. The successful application of the sterile insect technique (SIT) for the control of the New World screwworm Cochliomyia hominivorax and several species of fruit flies has given impetus to the use of this method for suppression or elimination of malaria vectors in some areas of Africa including Northern State of Sudan. The research and development phase of the Northern State feasibility study has been started. Sudanese stakeholders are working side-by-side with the International Atomic Energy Agency in the activities of this important phase. Several ethical, legal and social issues associated with this approach arose during this phase of the project. They need to be seriously considered and handled with care. In this paper, these issues are described, and the current and proposed activities to overcome potential hurdles to ensure success of the project are listed. PMID:19917073

  14. Cenozoic tectonic and climatic events in southern Iberian Peninsula: Implications for the evolutionary history of freshwater fish of the genus Squalius (Actinopterygii, Cyprinidae).

    PubMed

    Perea, Silvia; Cobo-Simon, Marta; Doadrio, Ignacio

    2016-04-01

    Southern Iberian freshwater ecosystems located at the border between the European and African plates represent a tectonically complex region spanning several geological ages, from the uplifting of the Betic Mountains in the Serravalian-Tortonian periods to the present. This area has also been subjected to the influence of changing climate conditions since the Middle-Upper Pliocene when seasonal weather patterns were established. Consequently, the ichthyofauna of southern Iberia is an interesting model system for analyzing the influence of Cenozoic tectonic and climatic events on its evolutionary history. The cyprinids Squalius malacitanus and Squalius pyrenaicus are allopatrically distributed in southern Iberia and their evolutionary history may have been defined by Cenozoic tectonic and climatic events. We analyzed MT-CYB (510 specimens) and RAG1 (140 specimens) genes of both species to reconstruct phylogenetic relationships and to estimate divergence times and ancestral distribution ranges of the species and their populations. We also assessed their levels of genetic structure and diversity as well as the amount of gene flow between populations. To investigate recent paleogeographical and climatic factors in southern Iberia, we modeled changes-through-time in sea level from the LGM to the present. Phylogenetic, geographic and population structure analyses revealed two well-supported species (S. malacitanus and S. pyrenaicus) in southern Iberia and two subclades (Atlantic and Mediterranean) within S. malacitanus. The origin of S. malacitanus and the separation of its Atlantic and Mediterranean populations occurred during the Serravalian-Tortonian and Miocene-Pliocene periods, respectively. These divergence events occurred in the Middle Pliocene and Pleistocene in S. pyrenaicus. In both species, Atlantic basins possessed populations with higher genetic diversity than Mediterranean, which may be explained by the Janda Lagoon. The isolation of S. malacitanus was

  15. Right-lateral displacements and the Holocene slip rate associated with prehistoric earthquakes along the southern Panamint Valley fault zone: Implications for southern Basin and Range tectonics and coastal California deformation

    SciTech Connect

    Peizhen Zhang; Ellis, M.; Slemmons, D.B.; Fengying Mao )

    1990-04-10

    The N 20{degree}W-trending Panamint Valley fault zone is linked to the N 60{degree}W-trending Hunter Mountain strike-slip fault and the Saline Valley fault system, which represents on of the three major fault systems accommodating active crustal extension in the southern Great Basin. The displacement associated with the most recent event, determined through six detailed topographic maps of offset features, is 3.2 {plus minus} 0.5 m, and a number of larger offsets, in range of 6-7 m and 12 m, are also observed. If the larger displacements represent, respectively, two and three events, each of {approximately} 3 m, then the fault zone appears to be associated with a characteristic earthquake, which the authors estimate from the length of the rupture zone and the displacement to be between (Ms) 6.5 and 7.2. The Holocene slip rate is 2.36 {plus minus} 0.79 mm/yr, is determined from the displacement of two alluvial features whose maximum age is estimated from pluvial shorelines. Assuming a characterisitc earthquake model, the recurrence interval is between 860 and 2,360 years. The total slip vector of the southern Panamint Valley fault system is oriented toward {approximately} N 35{degree}W, making this a predominately strike-slip fault. In conjunction with the N 60{degree}W orientation of the Hunter mountain strike-slip fault, the authors suggest that the displacement vector for the southern Great Basin is toward the NW, consistent with results from VLBI data, rather than WNW as determined by combining VLBI and geological data. This is turn suggests that the coastal California deformation component involves, respectively, less shortening and more strike-slip displacement perpendicular and parallel to the San Andreas fault than is currently proposed.

  16. Electrochemical determination of Sudan I in food products using a carbon nanotube-ionic liquid composite modified electrode.

    PubMed

    Liu, Benzhi; Yin, Chuntao; Wang, Min

    2014-01-01

    A sensitive and convenient electrochemical method was developed for the determination of Sudan I using a carbon nanotube-ionic liquid composite modified electrode with the enhancement effect of cetyltrimethyl ammonium bromide (CTAB). The modified electrode exhibited an obvious electrocatalytic activity towards the oxidation of Sudan I, and the oxidation peak current significantly increased in the presence of CTAB. The experimental parameters, such as solution pH, concentration of CTAB and accumulation time, were optimised for Sudan I determination. The oxidation peak current showed a linear relationship with the concentration of Sudan I in the range of 3.0 × 10(-8) to 3.1 × 10(-6) mol l(-1), with a detection limit of 8.0 × 10(-9) mol l(-1). The proposed method was successfully applied for the determination of Sudan I in food products of ketchup and chilli sauce. PMID:25254422

  17. Can differences in heat flow between east and southern Africa be easily interpreted?: Implications for understanding regional variability in continental heat flow

    NASA Astrophysics Data System (ADS)

    Nyblade, Andrew A.; Pollack, Henry N.

    1993-03-01

    We address the extent to which regional variations in continental heat flow can be interpreted, making use of a heat flow data set from east and southern Africa. The first-order observation deriving from these heat flow measurements is a common pattern characterized in both regions by low heat flow in Archean cratons and higher heat flow in younger mobile belts. Two regional differences between east and southern Africa are superimposed on this common heat flow pattern: (1) heat flow in the Tanzania Craton is about 13 mW m -2 lower than in the Kalahari Craton, and (2) heat flow in the Mozambique Belt in east Africa is about 9 mW m -2 lower than in the southern African mobile belts, within about 250 km of the respective Archean cratons. The differences in heat flow between east and southern Africa suggest that the thermal structure of the lithosphere beneath these regions differs somewhat, and we attempt to resolve these differences in lithospheric thermal structure by examining four explanations that could account for the heat flow observations: (1) diminished heat flow in shallow boreholes in east Africa; (2) less crustal heat production in the regions of lower heat flow; (3) thicker lithosphere beneath the regions of lower heat flow; (4) cooler mantle beneath the areas of lower heat flow. We find it difficult to interpret uniquely the heat flow differences between east and southern Africa because available constraints on crustal heat production, crustal structure, lithospheric thickness and mantle temperatures are insufficient to discriminate among the possible explanations. Hence, extracting significant information about lithospheric thermal structure from regional heat flow variations requires more ancillary geochemical and geophysical information than Africa presently offers.

  18. Molecular identification of different Theileria and Babesia species infecting sheep in Sudan.

    PubMed

    El Imam, Ahmed H; Hassan, Shawgi M; Gameel, Ahmed A; El Hussein, Abdelrahim M; Taha, Khalid M; Oosthuizen, Marinda C

    2016-01-01

    The epidemiological aspects of sheep piroplasmosis in Sudan are poorly studied, and further investigations using sensitive and precise techniques are required. In this study, the Reverse Line Blot (RLB) hybridization assay was used to detect and simultaneously differentiate between Theileria and Babesia species. DNA was extracted from blood collected on filter paper (n=219) from apparently healthy sheep from six different geographical localities in Sudan. Results indicated that Theileria ovis (88.6%), T. separata (20.1%), T. lestoquardi (16.4%) and T. annulata (16.4%) DNA could be detected in the blood samples. Single and mixed Theileria infections were detected in 74 (33.8%) and 124 (56.6%) respectively and T. ovis being the most prevalent species in the country. T. ovis and T. separata were reported for the first time in sheep in Sudan. PMID:27262957

  19. A new genus for a rare African vespertilionid bat: insights from South Sudan

    PubMed Central

    Reeder, DeeAnn M.; Helgen, Kristofer M.; Vodzak, Megan E.; Lunde, Darrin P.; Ejotre, Imran

    2013-01-01

    Abstract A new genus is proposed for the strikingly patterned African vespertilionid “Glauconycteris” superba Hayman, 1939 on the basis of cranial and external morphological comparisons. A review of the attributes of a newly collected specimen from South Sudan (a new country record) and other museum specimens of “Glauconycteris” superba suggests that “Glauconycteris” superba is markedly distinct ecomorphologically from other species classified in Glauconycteris and is likely the sister taxon to Glauconycteris sensu stricto. The recent capture of this rarely collected but widespread bat highlights the need for continued research in tropical sub-Saharan Africa and in particular, for more work in western South Sudan, which has received very little scientific attention. New country records for Glauconycteris cf. poensis (South Sudan) and Glauconycteris curryae (Gabon) are also reported. PMID:23805046

  20. Southern Africa

    Atmospheric Science Data Center

    2013-04-16

    article title:  Southern Africa     View larger JPEG image ... These Multi-angle Imaging SpectroRadiometer (MISR) images of Africa were acquired on August 25, 2000, during Terra orbit 3655. The left ... of smoke plumes and haze. The southern tip of South Africa is at the bottom of the image, and Zambia is at the top. Distinctive ...

  1. Genetic Diversity of the Outer Surface Protein C Gene of Southern Borrelia Isolates and Its Possible Epidemiological, Clinical, and Pathogenetic Implications

    PubMed Central

    Lin, Tao; Oliver, Jr., James H.; Gao, Lihui

    2002-01-01

    The ospC genes of 20 southern Borrelia strains were sequenced. The strains consisted of B. burgdorferi sensu stricto, B. andersonii, B. bissettii, one undescribed genospecies, MI-8, and one probably new Borrelia species, TXW-1. A high degree of similarity exists between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Lateral transfers of the ospC gene probably occurred between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Internal gene recombination appears to occur among them. The highest degree of genetic diversity among them was observed in the two variable domains (V1 and V2), semivariable domain (SV), and the species-specific epitopes (between amino acids 28 and 31). Differences in ospC sequences among southern strains reflect diversity at the strain and genospecies levels. MI-8, which was recognized as an undescribed genospecies in our previous reports, remains distinguishable in our current analysis of ospC genes and is distinct from B. burgdorferi sensu stricto. Interestingly, another undescribed southern isolate, TXW-1, was not amplified under various PCR conditions. Compared to European B. burgdorferi sensu stricto strains, American B. burgdorferi sensu stricto strains show greater genetic heterogeneity. Southern B. burgdorferi sensu stricto, B. andersonii, and B. bissettii isolates were intermixed with each other in the phylogenetic trees. In the derived trees in our work, at least one southeastern strain of B. burgdorferi, MI-2, most closely aligns with a so-called invasive cluster that possesses many proven human-invasive strains. Transmission experiments show that MI-2 and the strains in this group of southern spirochetes are able to infect mice and hamsters and that the typical vector of Lyme disease, Ixodes scapularis, can acquire the spirochetes from infected mammals. Currently, strain MI-2 appears to be the only southern isolate among the 20 we analyzed that

  2. A comparison of the physics of the northern and southern shelves of the eastern Bering Sea and some implications for the ecosystem

    NASA Astrophysics Data System (ADS)

    Stabeno, Phyllis J.; Farley, Edward V., Jr.; Kachel, Nancy B.; Moore, Sue; Mordy, Calvin W.; Napp, Jeffrey M.; Overland, James E.; Pinchuk, Alexei I.; Sigler, Michael F.

    2012-06-01

    Sufficient oceanographic measurements have been made in recent years to describe the latitudinal variation in the physics of the eastern Bering Sea shelf and the potential impact of climate change on the species assemblages in the two ecosystems (north and south). Many of the predicted ecosystem changes will result from alterations in the timing and extent of sea ice. It is predicted that the sea ice in the northern Bering Sea will be less common in May, but will continue to be extensive through April. In contrast, the southern shelf will have, on average, much less sea ice than currently observed, but with large interannual and multiyear variability until at least 2050. Thus, even under current climate warming scenarios, bottom temperatures on the northern shelf will remain cold. Based on biophysical measurements, the southern and northern ecosystems were divided by a North-South Transition at ˜60°N. The northern middle shelf was characterized by a freshwater lens at the surface, cold bottom temperatures, and a thicker pycnocline than found on the southern shelf. Subsurface phytoplankton blooms were common. In contrast, the southern shelf stratification was largely determined by temperature alone; the pycnocline was thin (often<3 m) and subsurface blooms were uncommon. Biological responses to climate warming could include greater north-south differences in zooplankton community structure, the transport of large Outer Shelf Domain crustacean zooplankton to the middle shelf, and the disappearance of two principal prey taxa (Calanus spp. and Thysanoessa spp.) of planktivorous fish, seabirds and whales. The response of commercially and ecologically important fish species is predicted to vary. Some species of fish (e.g., juvenile sockeye salmon, Oncorhynchus nerka) may expand their summer range into the northern Bering Sea; some (e.g., pink salmon, O. gorbuscha) may increase in abundance while still other species (e.g., walleye pollock and arrowtooth flounder

  3. Using apatite (U-Th)/He thermochronometry to resolve regional unroofing patterns across the interior of the southern African Plateau and implications for mantle dynamics

    NASA Astrophysics Data System (ADS)

    Stanley, J. R.; Flowers, R. M.

    2011-12-01

    The southern African Plateau is a long wavelength physiographic feature characterized by elevated Archean and Proterozoic cratonic lithosphere surrounded by a horseshoe shaped "Great Escarpment" which drops to the coastal plane. The average elevation of the plateau interior is ~1 km, ~0.5 km higher than average cratons. Unlike other major continental plateaus, southern Africa is surrounded by divergent margins which formed during the Jurassic breakup of Gondwana. The mechanisms for plateau uplift are intensely debated and include mantle drivers such as shallow convection or dynamic topography related to the southern African superplume. Constraining the timing and patterns of uplift can help to differentiate these competing explanations for the high topography. Thermochronological studies can yield critical information regarding unroofing histories to help decipher the timing and causes of plateau elevation gain. Previous studies using apatite fission-track (AFT) thermochronology mostly focused on transects across southern portions of the Great Escarpment. However, despite its importance for resolving large-scale unroofing patterns, there is limited thermochronological information from the plateau interior. This is in part because the temperature sensitivity of the AFT system may be somewhat higher than that required to tightly resolve the lower magnitudes of unroofing in the plateau interior relative to the coastal plain. The (U-Th)/He system in apatite (AHe) is particularly well-suited to this problem because its sensitivity to temperatures as low as ~30°C allows unroofing events in the upper 1-2 km of crust to be detected. Here we present the first AHe dataset from a broad swath across the interior of the plateau from northern South Africa and Botswana. New AHe data for eight Proterozoic diabase samples yield Cretaceous dates that display an interesting bimodal distribution of data. These results suggest at least 1.5 km of unroofing across this portion of the

  4. Characterization of epidemic and nonepidemic Neisseria meningitidis serogroup A strains from Sudan and Sweden.

    PubMed Central

    Salih, M A; Danielsson, D; Bäckman, A; Caugant, D A; Achtman, M; Olcén, P

    1990-01-01

    A random selection of 25 strains isolated during an epidemic caused by serogroup A Neisseria meningitidis in Sudan (1988), 3 preepidemic meningococcal strains (1985), and 26 serogroup A strains isolated from sporadic cases of meningitis in Sweden (1973 to 1987) were assessed for multilocus enzyme genotypes (ETs), DNA restriction enzyme patterns, outer membrane proteins, lipopolysaccharides, pilus formation, and antibiograms. All of the 25 Sudanese epidemic isolates and 22 of the Swedish strains were of the same or closely related ETs (ETs 3, 4, and 5), corresponding to clone III-1, which has been responsible for two pandemic waves in the last three decades. The earlier pandemic involved Scandinavia, and the last one caused an outbreak during the pilgrimage to Mecca, Saudi Arabia (August 1987), spreading to Sudan, Chad, and Ethiopia. The three Sudanese preepidemic isolates (1985) were clone IV-1 (sulfonamide susceptible), which has been resident in the African meningitis belt for the last 25 years. The uniformity of clone III-1 strains (all sulfonamide resistant) from Sudan and Sweden was confirmed by DNA restriction enzyme patterns. ETs 3, 4, and 5 from Sudan and Sweden had 86 to 100% similarity to a Swedish clone III-1 reference strain, whereas ETs 1, 2, 6, and 7 showed 50 to 80% similarity. Class 1 protein for clone III-1 showed serosubtype antigens P1.9 and P1.x, whereas ET6 strains (clone IV-1) had serosubtype P1.7. Lipopolysaccharides were variable in the Sudanese and Swedish strains. Pili were expressed in all clone III-1 isolates from Sudan and Sweden but in none of the clone IV-1 isolates (Sudan, 1985). Images PMID:1975593

  5. Drug-resistant malaria in Sudan: A review of evidence and scenarios for the future

    PubMed Central

    Adeel, Ahmed Awad

    2012-01-01

    Resistance of falciparum malaria to chloroquine (CQ) has gradually emerged in the late 1970s, reaching unacceptably high proportions over the following three decades of use as frst line treatment in Sudan. By 2004–2006 CQ was replaced by artemisinin-based combination treatment (ACTs), with combination of sulfadoxine-pyrimethamine (SP) and artesunate (AS) deployed as frst-line drug against falciparum malaria. The present review follows the evolution of CQ resistance in Sudan and the available evidence on the response to the present frst-line drugs. The fndings in Sudan are analyzed in view of developments in other African countries and at the global level, with the hope of elucidating possible scenarios for the course of events in the Sudan. Northern Sudan has been one of the areas where signals indicating the emergence of drug resistant malaria parasites have frst originated in Africa. The pattern of low endemicity and low population immunity to malaria, together with massive deployment and improper use of anti-malarial drugs created the ideal environment for creation of anti-malarial drug resistance. Such an environment existed in certain areas in South East Asia that had historically been the epicenter from which falciparum malaria parasites resistant to pyrimethamine and chloroquine have spread to the rest of the world. The alarming recent reports about the emergence of artemisinin (ART) resistance in South East Asia have lead WHO to take specifc measures for prevention, early detection and containment of drug resistance. What could be applicable in Sudan in these measures is discussed here.

  6. Towards global Guinea worm eradication in 2015: the experience of South Sudan.

    PubMed

    Awofeso, Niyi

    2013-08-01

    For centuries, the Guinea worm parasite (Dracunculus medinensis) has caused disabling misery, infecting people who drink stagnant water contaminated with the worm's larvae. In 2012, there were 542 cases of Guinea worm reported globally, of which 521 (96.1%) were reported in South Sudan. Protracted civil wars, an inadequate workforce, neglect of potable water provision programs, suboptimal Guinea worm surveillance and case containment, and fragmented health systems account for many of the structural and operational factors encumbering South Sudan's Guinea worm eradication efforts. This article reviews the impacts of six established Guinea worm control strategies in South Sudan: (1) surveillance to determine actual caseload distribution and trends in response to control measures; (2) educating community members from whom worms are emerging to avoid immersing affected parts in sources of drinking water; (3) filtering potentially contaminated drinking water using cloth filters or filtered drinking straws; (4) treating potentially contaminated surface water with the copepod larvicide temephos (Abate); (5) providing safe drinking water from boreholes or hand-dug wells; and (6) containment of transmission through voluntary isolation of each patient to prevent contamination of drinking water sources, provision of first aid, and manual extraction of the worm. Surveillance, community education, potable water provision, and case containment remain weak facets of the program. Abate pesticide is not a viable option for Guinea worm control in South Sudan. In light of current case detection and containment trends, as well as capacity building efforts for Guinea worm eradication, South Sudan is more likely to eradicate Guinea worm by 2020, rather than by 2015. The author highlights areas in which substantial improvements are required in South Sudan's Guinea worm eradication program, and suggests improvement strategies. PMID:23623648

  7. Seasonal variation of carbon fluxes in a sparse savanna in semi arid Sudan

    PubMed Central

    Ardö, Jonas; Mölder, Meelis; El-Tahir, Bashir Awad; Elkhidir, Hatim Abdalla Mohammed

    2008-01-01

    both during the dry and wet season 2005. The small sink during the dry season is surprising and similar dry season sinks have not to our knowledge been reported from other similar savanna ecosystems and could have potential management implications for agroforestry. A strong response of NEE versus small changes in plant available soil water content was found. Collection and analysis of flux data for several consecutive years including variations in precipitation, available soil moisture and labile soil carbon are needed for understanding the year to year variation of the carbon budget of this grass land/sparse savanna site in semi arid Sudan. PMID:19046418

  8. The curious case of the date of introduction of leaded fuel to Australia: Implications for the history of Southern Hemisphere atmospheric lead pollution

    NASA Astrophysics Data System (ADS)

    Cook, D. E.; Gale, S. J.

    By comparison with the Northern Hemisphere, the history of atmospheric lead pollution in the Southern Hemisphere is still poorly understood. Until recently, the main source of atmospheric lead fallout in the Southern Hemisphere was tetraethyl lead from motor fuel and for most of the 20th century the most important single source of this pollutant was Australia. Yet there is little agreement over when leaded fuel made its first appearance in Australia. Reported dates range from the early 1920s to the late 1940s. A study of oil company advertisements and reports in motoring and oil company journals shows that leaded petrol first became available in Australia in August 1932. This date is important both for the reconstruction of lead pollution histories and in the use of lead stratigraphies to determine chronology.

  9. Gravity anomalies, Quaternary vents, and Quaternary faults in the southern Cascade Range, Oregon and California: Implications for arc and backarc evolution

    NASA Astrophysics Data System (ADS)

    Blakely, Richard J.; Christiansen, Robert L.; Guffanti, Marianne; Wells, Ray E.; Donnelly-Nolan, Julie M.; Muffler, L. J. Patrick; Clynne, Michael A.; Smith, James G.

    1997-10-01

    Isostatic residual gravity anomalies in the southern Cascade Range of northern California and southern Oregon are spatially correlated with broad zones of Quaternary magmatism as reflected by the total volume of Quaternary volcanic products, the distribution of Quaternary vents, and the anomalously low teleseismic P wave velocities in the upper 30 km of crust. The orientation of Quaternary faults also appears to be related to gravity anomalies and volcanism in this area, trending generally north-south within the magmatic regions and northwest-southeast as they enter the neighboring amagmatic zones to the north and south. The relationship between gravity anomalies, vent density, and fault orientations may indicate in a broad sense the strength of the middle and upper crust. The southern Cascade Range occupies a transition zone where horizontal stress is transferred from the northwest-southeast dextral shear of the Walker Lane belt to the east-west extension characteristic of the Cascade arc in central Oregon. Faulting along north-south strikes in the volcanically active areas indicates the east-west extensional stresses in thermally weakened crust, whereas northwest faulting between the volcanically active areas reflects the northwest trending, right lateral shear strain of the Walker Lane belt. The segmentation of the arc reflected in Quaternary magmatism may be caused by differential extension behind crustal blocks of the forearc rotating clockwise with respect to North America. In this view the volcanic centers at Mount Shasta, Medicine Lake volcano, and Lassen Peak in northern California are situated along the southern parts of the trailing edges of two distinct segments of the forearc where additional extension is implied by their differential clockwise rotation.

  10. Marriage pattern in the Sudan and its interrelation with fertility.

    PubMed

    Khalifa, M

    1986-06-01

    The marriage pattern is an aspect of the social, economic and cultural conditions of a population. Recent changes taking place in Sudanese society are associated with a slight increase in the mean age at 1st marriage for females. Demographic and economic factors may be responsible for the change. The migration of Sudanese males at marriageable ages to the rich oil countries resulted in an unbalanced sex ratio which may be responsible for a marriage squeeze. The same effect is taking place as a result of high rural-urban migration. Increasing economic pressure has created a need for employment of women outside the home. This phenomenon has helped to change the role concept of both sexes and provided an alternative to early marriage. There has been a remarkable expansion of women's education in the Sudan since independence in 1956. Economic pressure has also affected the age at marriage by making marriage less feasible. Financial preparations for a marriage, in both urban and rural areas, appear to exert a significant pressure towards marital postponement. Postponement of marriage is associated with more marital stability and reductions in the amount of lost reproductive time. Also, the fertility of the women who marry late is only slightly less than that of those who marry young. Late marriers catch up with those who married young and the slight excess experienced by the young marriers takes place towards the end of the reproductive life. Changes in the Sudanese birth rate are not expected to accompany the process of development. The current level and effectiveness of birth control are not enough to affect fertility especially as it is not aimed at reducing the number of births. Reductions in the level of Sudanese fertility can be achieved only through improvement of the effectiveness of family planning programs. PMID:12280549

  11. The Holocene Geoarchaeology of the Desert Nile in Northern Sudan

    NASA Astrophysics Data System (ADS)

    Woodward, Jamie; Macklin, Mark; Spencer, Neal; Welsby, Derek; Dalton, Matthew; Hay, Sophie; Hardy, Andrew

    2016-04-01

    Invited Paper Forty years ago Colin Renfrew declared that "every archaeological problem starts as a problem in geoarchaeology" (Renfrew, 1976 p. 2). With this assertion in mind, this paper draws upon the findings from field research in two sectors of the Nile Valley of Northern Sudan dedicated to the exploration of human-environment interactions during the middle and late Holocene. This part of the Nile corridor contains a rich cultural record and an exceptionally well preserved Holocene fluvial archive. A distinctive feature of these records is the variety of evidence for interaction between desert and river over a range of spatial and temporal scales. This interaction presented both challenges and opportunities for its ancient inhabitants. This paper will present evidence for large-scale landscape changes driven by shifts in global climate. It will also show how we have integrated the archaeological and geological records in the Northern Dongola Reach and at Amara West - where long-term field projects led by archaeologists from the British Museum have recognised the importance of a sustained commitment to interdisciplinary research to achieve a fully integrated geoarchaeological approach across a range of scales. The former project is a large-scale landscape survey with multiple sites across an 80 km reach of the Nile whilst the latter has a strong focus on a single New Kingdom town site and changes in its environmental setting. By combining multiple archaeological and geological datasets - and pioneering the use of OSL dating and strontium isotope analysis in the Desert Nile - we have developed a new understanding of human responses to Holocene climate and landscape change in this region. Renfrew, C. (1976) Archaeology and the earth sciences. In: D.A. Davidson and M.I. Shackley (eds) Geoarchaeology: Earth Science and the Past, Duckworth, London, 1-5.

  12. Neonatal respiratory distress in Omdurman Maternity Hospital, Sudan

    PubMed Central

    Hamed, Selma MA; Nasr, Abdelhaleem

    2014-01-01

    Neonatal respiratory distress (NRD) is a common neonatal problem, which is responsible for high morbidity and mortality. There are few published studies in developing countries addressing neonatal respiratory distress. There is no previously published study in Sudan on this problem. The objective of the study is to determine the frequency, different causes, immediate outcome. It was a prospective, descriptive, cross sectional hospital-based study which was carried out in neonatal intensive care unit (NICU) of Omdurman Maternity Hospital, between February-March 2013. The study enrolled all Sudanese newborns from 0-28 days including normal, low and high birth weight of different gestational ages admitted to the neonatal intensive care unit and diagnosed as neonatal respiratory distress. The frequency of NRD was calculated, the causes and immediate outcome were determined. Results showed that the frequency rate of NRD was (4.83%) among the total number of hospital (2071) live births during the period of the study. The commonest causes were transient tachypnoea of the newborn (TTN) in 28% of cases, sepsis in 24% of cases and hyaline membrane disease (HMD) in 15% of cases. The outcome of NRD was: cure in 56% of cases, death in 36% of cases, and patients discharged with complications in 8% of cases. In conclusion, the study confirmed the importance of NRD with a frequency rate of 4.83%, morbidity of 8% and mortality of 36% of cases. The causes and immediate outcome were determined and discussed. Some recommendations were suggested in order to reduce its frequency, morbidity and mortality. PMID:27493392

  13. A New Model for Management of Mycetoma in the Sudan

    PubMed Central

    Fahal, Ahmed; Mahgoub, El Sheikh; EL Hassan, Ahmed Mohamed; Abdel-Rahman, Manar Elsheikh; Alshambaty, Yassir; Hashim, Ahmed; Hago, Ali; Zijlstra, Eduard E.

    2014-01-01

    Patients with mycetoma usually present late with advanced disease, which is attributed to lack of medical and health facilities in endemic areas, poor health education and low socio-economic status. With this background, an integrated patient management model at the village level was designed to address the various problems associated with mycetoma. The model was launched in an endemic village in the Sudan, between 2010 and 2013. This model is described in a prospective, descriptive, community-based study, aimed to collect epidemiological, ecological, and clinical data and to assess knowledge, attitude and practice (KAP) in order to design effective and efficient management measures. In this study, the prevalence of mycetoma was 14.5 per 1,000 inhabitants. The patients were farmers, housewives and children of low socio-economic status, and no obvious risk group was detected. All had surgery performed in a mobile surgical unit in the village which encouraged patients to present early with small early lesion leading to a good clinical outcome. The close contact with the Acacia tree thorns, animals and animal dung, walking bare footed and practising poor hygiene may all have contributed to the development of mycetoma in the village. Knowledge of mycetoma was poor in 96.3% of the study population, 70% had appropriate attitudes and beliefs towards interaction with mycetoma patients and treatment methods, and 49% used satisfactory or good practices in the management of mycetoma. Knowledge and practices on mycetoma were found to be significantly associated with age. Based on the KAP and epidemiological data, several health education sessions were conducted in the village for different target groups. The integrated management approach adopted in this study is unique and appeared successful and seems suitable as an immediate intervention. While for the longer term, establishment of local health facilities with trained health staff remains a priority. PMID:25356640

  14. Association of tomato leaf curl Sudan virus with leaf curl disease of tomato in Jeddah, Saudi Arabia.

    PubMed

    Sohrab, Sayed Sartaj; Yasir, Muhammad; El-Kafrawy, Sherif Ali; Abbas, Ayman T; Mousa, Magdi Ali Ahmed; Bakhashwain, Ahmed A

    2016-06-01

    Tomato is an important vegetable crop and its production is adversely affected by leaf curl disease caused by begomovirus. Leaf curl disease is a serious concern for tomato crops caused by begomovirus in Jeddah, Kingdom of Saudi Arabia. Tomato leaf curl disease has been shown to be mainly caused either by tomato leaf curl Sudan virus or tomato yellow leaf curl virus as well as tomato leaf curl Oman virus. Many tomato plants infected with monopartite begomoviruses were also found to harbor a symptom enhancing betasatellites. Here we report the association of tomato leaf curl Sudan virus causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia. The complete genome sequence analysis showed highest (99.9 %) identity with tomato leaf curl Sudan virus causing leaf curl disease in Arabian Peninsula. In phylogenetic relationships analysis, the identified virus formed closest cluster with tomato leaf curl Sudan virus. In recombination analysis study, the major parent was identified as tomato leaf curl Sudan virus. Findings of this study strongly supports the associated virus is a variant of tomato leaf curl Sudan virus causing disease in Sudan, Yemen and Arabian Peninsula. The betasatellites sequence analysis showed highest identity (99.8 %) with tomato leaf curl betasatellites-Amaranthus-Jeddah. The phylogenetic analysis result based on betasatellites formed closed cluster with tomato yellow leaf curl Oman betasatellites. The importance of these findings and occurrence of begomovirus in new geographic regions causing leaf curl disease of tomato in Jeddah, Kingdom of Saudi Arabia are discussed. PMID:27366765

  15. Gender differences in the prevalence and determinants of tobacco use among school-aged adolescents (11 – 17 years) in Sudan and South Sudan

    PubMed Central

    Atari, Dominic Odwa

    2014-01-01

    Introduction Tobacco use is one of the leading and preventable causes of global morbidities and premature mortalities. The study explores gender differences in the prevalence and determinants of tobacco use among school-aged adolescents (11-17years) in Sudan and South Sudan. Methods The study utilized the national Global Youth Tobacco Survey (GYTS) data collected in 2005 for Sudan (4,277 unweighted; 131,631 weighted). Univariate and bivariate analyses were conducted to examine the associations between the dependent (tobacco use status) and independent variables. Logistic regression analyses were performed to identify the key factors which influence tobacco consumption among adolescents in the 2 Sudans for ever cigarette users, current cigarette users, and users of noncigarette tobacco products. Results There were significant gender differences in the prevalence of ever cigarette users (21.8%; male=13.1%, female=6.5%, p<0.05) and current cigarette users (6.9%; male=4.9%, female = 1.3%, p<0.05) but not among users of noncigarette tobacco products (14.7%; male=6.8%, female=6.1%). Adolescent tobacco use was significantly associated with availability of monthly income or allowance, exposure to tobacco industry promotions, and tobacco-use behavior of familial relations. Knowledge about the harmful effects of secondhand smoke was related with decreased likelihood of tobacco use. Conclusion School programs that focus on health messages alone may not work for the adolescent population. Legislations that ban all types of tobacco advertisements, promotions, and sponsorships among adolescents are needed in the 2 countries. PMID:25404978

  16. Hydrocarbon potential evaluation of the source rocks from the Abu Gabra Formation in the Sufyan Sag, Muglad Basin, Sudan

    NASA Astrophysics Data System (ADS)

    Qiao, Jinqi; Liu, Luofu; An, Fuli; Xiao, Fei; Wang, Ying; Wu, Kangjun; Zhao, Yuanyuan

    2016-06-01

    The Sufyan Sag is one of the low-exploration areas in the Muglad Basin (Sudan), and hydrocarbon potential evaluation of source rocks is the basis for its further exploration. The Abu Gabra Formation consisting of three members (AG3, AG2 and AG1 from bottom to top) was thought to be the main source rock formation, but detailed studies on its petroleum geology and geochemical characteristics are still insufficient. Through systematic analysis on distribution, organic matter abundance, organic matter type, organic matter maturity and characteristics of hydrocarbon generation and expulsion of the source rocks from the Abu Gabra Formation, the main source rock members were determined and the petroleum resource extent was estimated in the study area. The results show that dark mudstones are the thickest in the AG2 member while the thinnest in the AG1 member, and the thickness of the AG3 dark mudstone is not small either. The AG3 member have developed good-excellent source rock mainly with Type I kerogen. In the Southern Sub-sag, the AG3 source rock began to generate hydrocarbons in the middle period of Bentiu. In the early period of Darfur, it reached the hydrocarbon generation and expulsion peak. It is in late mature stage currently. The AG2 member developed good-excellent source rock mainly with Types II1 and I kerogen, and has lower organic matter abundance than the AG3 member. In the Southern Sub-sag, the AG2 source rock began to generate hydrocarbons in the late period of Bentiu. In the late period of Darfur, it reached the peak of hydrocarbon generation and its expulsion. It is in middle mature stage currently. The AG1 member developed fair-good source rock mainly with Types II and III kerogen. Throughout the geological evolution history, the AG1 source rock has no effective hydrocarbon generation or expulsion processes. Combined with basin modeling results, we have concluded that the AG3 and AG2 members are the main source rock layers and the Southern Sub-sag is

  17. Southern Rains

    Atmospheric Science Data Center

    2014-05-15

    ...   View Larger image Vigorous vegetation growth in the Southern United States after heavy rains fell during April and ... for atmospheric scattering and absorption effects, and use plant canopy structural models to determine the partitioning of solar ...

  18. A cosmogenic 10Be chronology for the local last glacial maximum and termination in the Cordillera Oriental, southern Peruvian Andes: Implications for the tropical role in global climate

    NASA Astrophysics Data System (ADS)

    Bromley, Gordon R. M.; Schaefer, Joerg M.; Hall, Brenda L.; Rademaker, Kurt M.; Putnam, Aaron E.; Todd, Claire E.; Hegland, Matthew; Winckler, Gisela; Jackson, Margaret S.; Strand, Peter D.

    2016-09-01

    Resolving patterns of tropical climate variability during and since the last glacial maximum (LGM) is fundamental to assessing the role of the tropics in global change, both on ice-age and sub-millennial timescales. Here, we present a10Be moraine chronology from the Cordillera Carabaya (14.3°S), a sub-range of the Cordillera Oriental in southern Peru, covering the LGM and the first half of the last glacial termination. Additionally, we recalculate existing 10Be ages using a new tropical high-altitude production rate in order to put our record into broader spatial context. Our results indicate that glaciers deposited a series of moraines during marine isotope stage 2, broadly synchronous with global glacier maxima, but that maximum glacier extent may have occurred prior to stage 2. Thereafter, atmospheric warming drove widespread deglaciation of the Cordillera Carabaya. A subsequent glacier resurgence culminated at ∼16,100 yrs, followed by a second period of glacier recession. Together, the observed deglaciation corresponds to Heinrich Stadial 1 (HS1: ∼18,000-14,600 yrs), during which pluvial lakes on the adjacent Peruvian-Bolivian altiplano rose to their highest levels of the late Pleistocene as a consequence of southward displacement of the inter-tropical convergence zone and intensification of the South American summer monsoon. Deglaciation in the Cordillera Carabaya also coincided with the retreat of higher-latitude mountain glaciers in the Southern Hemisphere. Our findings suggest that HS1 was characterised by atmospheric warming and indicate that deglaciation of the southern Peruvian Andes was driven by rising temperatures, despite increased precipitation. Recalculated 10Be data from other tropical Andean sites support this model. Finally, we suggest that the broadly uniform response during the LGM and termination of the glaciers examined here involved equatorial Pacific sea-surface temperature anomalies and propose a framework for testing the viability

  19. Spatio-temporal spawning and larval dynamics of a zebra mussel (Dreissena polymorpha) population in a North Texas Reservoir: implications for invasions in the southern United States

    USGS Publications Warehouse

    Churchill, Christopher John

    2013-01-01

    Zebra mussels were first observed in Texas in 2009 in a reservoir (Lake Texoma) on the Texas-Oklahoma border. In 2012, an established population was found in a near-by reservoir, Ray Roberts Lake, and in June 2013, settled mussels were detected in a third north Texas reservoir, Lake Lewisville. An established population was detected in Belton Lake in September 2013. With the exception of Louisiana, these occurrences in Texas mark the current southern extent of the range of this species in the United States. Previous studies indicate that zebra mussel populations could be affected by environmental conditions, especially increased temperatures and extreme droughts, which are characteristic of surface waters of the southern and southwestern United States. Data collected during the first three years (2010–12) of a long-term monitoring program were analyzed to determine if spatio-temporal zebra mussel spawning and larval dynamics were related to physicochemical water properties in Lake Texoma. Reproductive output of the local population was significantly related to water temperature and lake elevation. Estimated mean date of first spawn in Lake Texoma was approximately 1.5 months earlier and peak veliger densities were observed two months earlier than in Lake Erie. Annual maximum veliger density declined significantly during the study period (p < 0.0001). A population crash occurred as a result of thermal stress and variability of lake elevation. In summer 2011, water temperatures peaked at 34.3°C and lake elevation declined to the lowest level recorded during the previous 18 years, which resulted in desiccation of substantial numbers of settled mussels in littoral zones. Veliger spatial distributions were associated with physicochemical stratification characteristics. Veligers were observed in the deepest oxygenated water after lake stratification, which occurred in late spring. Results of this study indicate environmental conditions can influence variability of

  20. Provenance of the Passo Feio complex, Dom Feliciano Belt: Implications for the age of supracrustal rocks of the São Gabriel Arc, southern Brazil

    NASA Astrophysics Data System (ADS)

    Lopes, Carina Graciniana; Pimentel, Marcio Martins; Philipp, Ruy Paulo; Gruber, Leonardo; Armstrong, Richard; Junges, Sergio

    2015-03-01

    The Passo Feio complex (PFC) is a sequence of metapelite, amphibolite, metavolcanic/metavolcanoclastic rocks, marble, calc-silicate rocks, quartzite and magnesium schist. It is part of the São Gabriel Terrane, a Neoproterozoic juvenile arc formed during the early stages of evolution of the Neoproterozoic Dom Feliciano Belt (DFB), in southern Brazil. This belt corresponds to the southernmost portion of the Mantiqueira Province, an important Neoproterozoic orogenic system exposed in the NNE direction along the southeastern coast of Brazil. The geotectonic significance of the original Passo Feio basin in the tectonic evolution of São Gabriel Terrene is not well understood. It has been considered as part of a passive margin sequence or as a back-arc sequence. Geochronological and isotopic data are very scarse for the Passo Feio rocks and this has hampered the better understanding of its significance in the Neoproterozoic tectonic evolution of southern Brazil. In the present study the age and significance of metasedimentary rocks of the PFC were investigated. The provenance study was carried out in four metapelite samples from the southern and northern Passo Feio complex, using U-Pb dating of detrital zircon. The results showed varied provenance patterns and zircon ages range from 3637 to 803 Ma. Paleo- and Mesoproterozoic detrital zircon grains are present in all samples, but an important Neoproterozoic population has been identified in one of them. 3.5 Ga old zircon grains form the oldest population of detrital zircon ever reported in southern Brazil. Paleoproterozoic/Archean terranes within the Rio de la Plata Craton may represent the main source of detrital sediments and this suggests that part of the Passo Feio complex might have been a passive margin sequence, developed along the northeastern margin of that paleocontinent. However, the presence of a Neoproterozoic zircon population is not consistent with derivation solely from the craton and indicates

  1. Organochlorine contaminants in blubber from stranded marine mammals collected from the Northern Oregon and Southern Washington coasts: implications for re-introducing California Condors, Gymnogyps californianus, in Oregon.

    PubMed

    Gundersen, Deke T; Duffield, Deborah A; Randall, Tina; Wintle, Nate; D'Alessandro, Dalin N; Rice, James M; Shepherdson, David

    2013-03-01

    Re-introduction of California Condors into Oregon is currently being considered, but there are concerns about the safety of potential food sources of this species. Condors are opportunistic feeders and a largely available food source for this species will be stranded marine mammal carcasses. We analyzed 37 blubber samples from 7 different marine mammal species collected from the Oregon and Southern Washington coasts for 18 organochlorine (OC) pesticides and 16 polychlorinated biphenyls (PCBs). Dichlorodiphenyldichloroethylene (DDE) was the most prevalent OC contaminant, making up more than 58 % of the total OC concentration measured. There were no significant differences in OC content between species or sexes. PMID:23275975

  2. Record of Cenozoic sedimentation from the Amanos Mountains, Southern Turkey: implications for the inception and evolution of the Arabia-Eurasia continental collision

    NASA Astrophysics Data System (ADS)

    Boulton, S. J.

    2009-04-01

    The sedimentary succession of the southern Amanos Mountains, bordering the eastern margin of the Karasu Rift in south central Turkey, provides a record of environmental change from the Eocene (Lutetian) to the Upper Miocene (Tortonian) charting the final evolution of the northern Arabian plate margin prior to, and during, continental collision. Eocene shallow-marine carbonates (Hacıdağı Formation) are interpreted as the youngest unit of the Arabian passive margin succession deposited on a northwards facing carbonate ramp. Subsequent deformation and uplift took place during the Oligocene represented by folding of the Eocene and older strata. Unconformably overlying the Eocene limestone are Lower Miocene conglomerates, sandstones and palaeosols up to 150 m thick (Kıcı Formation). These were deposited in a range of marginal marine settings consisting of alluvial fan, flood plain and shallow marine/lower shoreface environments interpreted as a ‘fan-delta' prograding from the uplifted proto-Amanos into a marine embayment. Subsequently, during the Middle Miocene, local patch reefs developed in restricted areas (Kepez Formation) followed by Upper Miocene sediments (Gökdere Formation) composed of deeper water marine marl, with clastic interbeds, which represents a transgression during this period. The Upper Miocene becomes sandier upwards, this records the regression from the relatively deep water facies to coastal sediments. Water depth gradually became shallower until during the Pliocene the area became continental. By the Quaternary rifting had resulted in the development of the Karasu Rift with active alluvial fans along the margins and braided rivers depositing coarse conglomerates in the axial zone. These conglomerates are interbedded with basaltic lava flows that resulted from the regional extension across the area. This research shows that initial continental collision occurred in this area after the Lutetian (40.4 Ma) and before the Aquitanian (23.03 Ma

  3. Record of Cenozoic sedimentation from the Amanos Mountains, Southern Turkey: Implications for the inception and evolution of the Arabia-Eurasia continental collision

    NASA Astrophysics Data System (ADS)

    Boulton, Sarah J.

    2009-04-01

    The sedimentary succession of the southern Amanos Mountains, bordering the eastern margin of the Karasu Rift in south central Turkey, provides a record of environmental change from the Eocene (Lutetian) to the Upper Miocene (Tortonian) that charts the final evolution of the northern margin of the Arabian plate prior to and during continental collision. Eocene shallow-marine carbonates (Hacıdağı Formation) are interpreted as the youngest unit of the Arabian passive margin succession deposited on a northwards facing carbonate ramp. Subsequent deformation and uplift took place during the Oligocene represented by folding of the Eocene and older strata. This is interpreted to be the result of initial continental collision between Arabia and Eurasia. Unconformably overlying the Eocene limestone are Lower Miocene conglomerates, sandstones and palaeosols up to 150 m thick (Kıcı Formation). These were deposited in a range of marginal marine settings consisting of alluvial fan/fan delta facies, flood plain as well as basinal facies. Subsequently, during the Middle Miocene, local patch reefs developed in restricted areas (Kepez Formation) followed by Upper Miocene sediments (Gökdere Formation) composed of relatively deep water hemipelagic marl, with clastic interbeds, which represent a transgression during this period. The Upper Miocene becomes sandier upwards, this records the regression from the relatively deep water facies to coastal sediments. Water depth gradually became shallower until during Pliocene time the area became continental in nature. By the Quaternary rifting had resulted in the development of the Karasu Rift with active alluvial fans along the margins and braided rivers depositing coarse conglomerates in the axial zone. These conglomerates are interbedded with basaltic lava flows that resulted from the region extension across the area. This research shows that initial continental collision occurred in this area after the Lutetian (40.4 Ma) and before

  4. Feasibility of health systems strengthening in South Sudan: a qualitative study of international practitioner perspectives

    PubMed Central

    Jones, Abigail; Legido-Quigley, Helena

    2015-01-01

    Objective To explore the feasibility of health systems strengthening from the perspective of international healthcare implementers and donors in South Sudan. Design A qualitative interview study, with thematic analysis using the WHO health system building blocks framework. Setting South Sudan. Participants 17 health system practitioners, working for international agencies in South Sudan, were purposively sampled for their knowledge and experiences of health systems strengthening, services delivery, health policy and politics in South Sudan. Results Participants universally reported the health workforce as insufficient and of low capacity and service delivery as poor, while access to medicines was restricted by governmental lack of commitment in undertaking procurement and supply. However, progress was clear in improved county health department governance, health management information system functionality, increased health worker salary harmonisation and strengthened financial management. Conclusions Resurgent conflict and political tensions have negatively impacted all health system components and maintaining or continuing health system strengthening has become extremely challenging. A coordinated approach to balancing humanitarian need particularly in conflict-affected areas, with longer term development is required so as not to lose improvements gained. PMID:26700280

  5. Urbanization, Culture, and Helpfulness: Cross-Cultural Studies in England and the Sudan.

    ERIC Educational Resources Information Center

    Yousif, Yousif; Korte, Charles

    1995-01-01

    Studies the "urban unhelpfulness" effect in England and the Sudan and the validity of cultural and dispositional explanations that have been put forward to explain it. Responses from 270 participants show the urban unhelpfulness effect to be quite equivalent in both countries. Additionally, the dispositional explanation was not supported in light…

  6. Population-Level Effect of Cholera Vaccine on Displaced Populations, South Sudan, 2014

    PubMed Central

    Rumunu, John; Abubakar, Abdinasir; West, Haley; Ciglenecki, Iza; Helderman, Trina; Wamala, Joseph Francis; Vázquez, Olimpia de la Rosa; Perea, William; Sack, David A.; Legros, Dominique; Martin, Stephen; Lessler, Justin; Luquero, Francisco J.

    2016-01-01

    Following mass population displacements in South Sudan, preventive cholera vaccination campaigns were conducted in displaced persons camps before a 2014 cholera outbreak. We compare cholera transmission in vaccinated and unvaccinated areas and show vaccination likely halted transmission within vaccinated areas, illustrating the potential for oral cholera vaccine to stop cholera transmission in vulnerable populations. PMID:27192187

  7. 48 CFR 52.225-20 - Prohibition on Conducting Restricted Business Operations in Sudan-Certification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Restricted Business Operations in Sudan-Certification. 52.225-20 Section 52.225-20 Federal Acquisition... Operations in Sudan—Certification. As prescribed at 25.1103(d), insert the following provision: Prohibition on Conducting Restricted Business Operations in Sudan—Certification (AUG 2009) (a) Definitions....

  8. 48 CFR 52.225-20 - Prohibition on Conducting Restricted Business Operations in Sudan-Certification.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Restricted Business Operations in Sudan-Certification. 52.225-20 Section 52.225-20 Federal Acquisition... Operations in Sudan—Certification. As prescribed at 25.1103(d), insert the following provision: Prohibition on Conducting Restricted Business Operations in Sudan—Certification (AUG 2009) (a) Definitions....

  9. 48 CFR 52.225-20 - Prohibition on Conducting Restricted Business Operations in Sudan-Certification.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Restricted Business Operations in Sudan-Certification. 52.225-20 Section 52.225-20 Federal Acquisition... Operations in Sudan—Certification. As prescribed at 25.1103(d), insert the following provision: Prohibition on Conducting Restricted Business Operations in Sudan—Certification (AUG 2009) (a) Definitions....

  10. The Sociolinguistics of Nationalism in the Sudan: The Politicisation of Arabic and the Arabicisation of Politics

    ERIC Educational Resources Information Center

    Abdelhay, Ashraf; Makoni, Busi; Makoni, Sinfree; Mugaddam, Abdel Rahim

    2011-01-01

    This monograph describes the historiography of language ideologies that led to the politicisation of Arabic and the Arabicisation of politics in the Sudan, starting from British colonial rule until the Comprehensive Peace Agreement that was a precursor to the separation of the South as an independent state. The monograph shows that the…

  11. 48 CFR 52.225-20 - Prohibition on Conducting Restricted Business Operations in Sudan-Certification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Restricted Business Operations in Sudan-Certification. 52.225-20 Section 52.225-20 Federal Acquisition... Operations in Sudan—Certification. As prescribed at 25.1103(d), insert the following provision: Prohibition on Conducting Restricted Business Operations in Sudan—Certification (AUG 2009) (a) Definitions....

  12. A Basic Hybrid Library Support Model to Distance Learners in Sudan

    ERIC Educational Resources Information Center

    Abdelrahman, Omer Hassan

    2012-01-01

    Distance learning has flourished in Sudan during the last two decades; more and more higher education institutions offer distance learning programmes to off-campus students. Like on-campus students, distance learners should have access to appropriate library and information support services. They also have specific needs for library and…

  13. The Naivasha Language Policy: The Language of Politics and the Politics of Language in the Sudan

    ERIC Educational Resources Information Center

    Abdelhay, Ashraf Kamal; Makoni, Busi; Makoni, Sinfree Bullock

    2011-01-01

    This article provides a textual analysis of the Naivasha language provisions in Sudan in an attempt to explore how political discourse is manifested in each policy statement. Using Critical Discourse Analysis (CDA) as an analytic and interpretive framework, the article argues that the Naivasha language provisions as political discourse are shaped…

  14. 48 CFR 52.225-20 - Prohibition on Conducting Restricted Business Operations in Sudan-Certification.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Restricted Business Operations in Sudan-Certification. 52.225-20 Section 52.225-20 Federal Acquisition... Operations in Sudan—Certification. As prescribed at 25.1103(d), insert the following provision: Prohibition on Conducting Restricted Business Operations in Sudan—Certification (AUG 2009) (a) Definitions....

  15. Reaching out and Partnering in the Sudan through Integrated Community-Oriented Teaching

    ERIC Educational Resources Information Center

    Abdelrahman, Samira; Al Fadil, Sumaia

    2011-01-01

    Community-university partnerships, if they are to be successful, must be firmly grounded in the context in which they take place. This paper describes the ways in which the University of Gezira in the Sudan from its very beginning was built on an understanding of rural communities. The university's Faculty of Medicine built its training around…

  16. 3 CFR - Certification Concerning U.S. Participation in the United Nations Mission in South Sudan...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 3 The President 1 2013-01-01 2013-01-01 false Certification Concerning U.S. Participation in the United Nations Mission in South Sudan Consistent With Section 2005 of the American Servicemembers' Protection Act Presidential Documents Other Presidential Documents Memorandum of January 10, 2012 Certification Concerning U.S. Participation in...

  17. South Sudan: Stakeholders' Views of Technical and Vocational Education and Training and a Framework for Action

    ERIC Educational Resources Information Center

    Atari, Dominic Odwa; McKague, Kevin

    2015-01-01

    The Republic of South Sudan, recently emerging from the longest civil war in contemporary African history, has set goals towards post-conflict reconstruction in many areas of social services. However, the educational infrastructure continues to struggle, and many stakeholders in government and international and local organisations are not…

  18. Risk Factors for Sustained Cholera Transmission, Juba County, South Sudan, 2014.

    PubMed

    Ujjiga, Thomas T A; Wamala, Joseph F; Mogga, Juma J H; Othwonh, Thabo O; Mutonga, David; Kone-Coulibaly, Asta; Shaikh, Masood Ali; Mpairwe, Allan M; Abdinasir, Abubaker; Abdi, Mohamed A; Yoti, Zabulon; Olushayo, Olu; Nyimol, Pinyi; Lul, Riek; Lako, Richard L; Rumunu, John

    2015-10-01

    We conducted a case-control study to identify risk factors for the 2014 cholera outbreak in Juba County, South Sudan. Illness was associated with traveling or eating away from home; treating drinking water and receiving oral cholera vaccination were protective. Oral cholera vaccination should be used to complement cholera prevention efforts. PMID:26402715

  19. Resilience and Culture/Ethnicity Examples from Sudan, Namibia, and Armenia.

    ERIC Educational Resources Information Center

    Grotberg, Edith H.

    This study examined cultural/ethnic similarities and differences in ways to promote resilience in children identified in the International Resilience Research Project (IRRP), focusing on Sudan, Namibia, and Armenia. Child resilience was assessed through the child's responses to a hypothetical situation in which a child is teased and frightened by…

  20. Flow injection chemiluminescence determination of sudan I in hot chilli sauce.

    PubMed

    Liu, Yanhong; Song, Zhenghua; Dong, Faxin; Zhang, Lin

    2007-02-01

    A chemiluminescence method based on the luminol-H2O2 system with flow injection technology was proposed for the determination of sudan I in hot chilli sauce. It was found that sudan I could enhance chemiluminescence intensity generated from the luminol-H2O2 system. The increment of chemiluminescence intensity was proportional to the concentration of sudan I, giving a calibration graph linear over the concentration from 10 pg mL-1 to 7 ng mL-1 (R 2 = 0.9980) with the detection limit of 3 pg mL-1 (3sigma) and the quantification limit of 7.5 pg mL-1. At a flow rate of 2.0 mL min-1, one analysis cycle, including sampling and washing, could be accomplished in 60 s with a relative standard deviation of <5.0%. The method has been applied successfully to the determination of sudan I in Pixian douban, Golden Mark guilin chilli sauce, and Golden Mark satay sauce, and the recovery was 90.6-110.0%. PMID:17263450

  1. Sub-regional integration in Sudan: the key to food security and recovery.

    PubMed

    D'Silva, Brian; Tecosky, Olivia

    2007-03-01

    The signing of the Comprehensive Peace Agreement (CPA) in Sudan has created a new opportunity for peace. Approaches to food security must now be reoriented based on the agro-ecological diversity in Sudan. WFP is in a unique position to catalyse an approach to food security that meets immediate needs and contributes to long-term recovery, in collaboration with the Government of National Unity (GNU) and the Government of South Sudan (GOSS). Aggregate food production in Sudan has increased in the past decade. At sub-regional levels, however, many areas remain food insecure. Major research must be undertaken to identify optimum levels of food production and barriers to access to food at sub-regional levels as a first step towards linking deficit areas with areas of surplus. Initiatives must also be undertaken to facilitate increased integration between sub-regions. Increased sub-regional linkages could ensure more efficient delivery of food in the short term as well as recovery and economic growth in the long term. PMID:17349002

  2. Geologic assessment of the fossil energy and geothermal potential of the Sudan

    SciTech Connect

    Setlow, L.W.

    1983-01-01

    This preliminary report provides geological input to the consideration of appropriate activities that can enhance the exploration and development of fossil-fuel and possible geothermal energy resources of the Sudan, and is based on study of available literature in early 1982. 59 references, 16 figures, 7 tables.

  3. 3 CFR - Continuation of the National Emergency With Respect to Sudan

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false Continuation of the National Emergency With Respect... of the National Emergency With Respect to Sudan On November 3, 1997, by Executive Order 13067, the... November 3, 1997, as expanded on April 26, 2006, and with respect to which additional steps were taken...

  4. Fluorescent nanomicelles for selective detection of Sudan dye in Pluronic F127 aqueous media.

    PubMed

    Ye, Xinliang; Zhang, Jie; Chen, Hui; Wang, Xiaohui; Huang, Fei

    2014-04-01

    Novel self-assembled water-soluble nanomicelles that contain fluorescent conjugated polymers (poly(9,9-dioctylfluorene) (PFO) or poly[2,7-(9,9-dihexylfluorene)-alt-4,4'-phenylether] (PF-PE)) have been obtained and used as the highly sensitive/selective platform for Sudan dye detection. The Fluorescent nanomicelles exhibited a highly selective fluorescence quenching by the prohibited food additive Sudan I, while not for the natural pigments: Capsanthin and Beta-carotene, due to the more suitable matching of the LUMOs (lowest unoccupied molecular orbital) of the conjugated polymers with that of Sudan I molecules. The Stern-Volmer constants (K(SV)) of PF-PE/F127 and PFO/F127 for Sudan I were 1,040,480 and 665,000 M(-1), respectively, which were more than 100 times higher than those of the same conjugated polymers in the orgainc solvents. The significantly enhanced sensitivity was due to the collective effect of the F127 micelles to both chromophore and analyte, through which the fluorophone-analyte binding interaction is significantly strengthened and efficient photoinduced charge transfer occurs. The as-proposed materials and approach may be potentially applied in the real-time food safety screening. PMID:24625370

  5. Research On: Motivation to Learn English among College Students in Sudan

    ERIC Educational Resources Information Center

    Humaida, Ibrahim Abdelrahim Ibrahim

    2012-01-01

    This research was conducted to achieve the following objectives: to examine motivation to learn English language among students of faculty of arts, Islamic University-Sudan, to find out if there were significant statistical differences on motivation scores related to both student level and age. To pursue these objectives, the researcher used the…

  6. 31 CFR 538.209 - Prohibited transportation-related transactions involving Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited transportation-related transactions involving Sudan. 538.209 Section 538.209 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY...

  7. 31 CFR 538.205 - Prohibited exportation and reexportation of goods, technology, or services to Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited exportation and reexportation of goods, technology, or services to Sudan. 538.205 Section 538.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF...

  8. 31 CFR 538.204 - Prohibited importation of goods or services from Sudan.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Prohibited importation of goods or services from Sudan. 538.204 Section 538.204 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY SUDANESE...

  9. 78 FR 8360 - Addition of South Sudan to the Restricted Destinations List

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-06

    .... FOR FURTHER INFORMATION CONTACT: Brooke G. Smith, Senior International Policy Analyst, Office of International Programs, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; telephone: 301-415- 2347... support for acts of international terrorism does not apply to South Sudan. In light of the foregoing,...

  10. Civic Education and Peacebuilding: Examples from Iraq and Sudan. Special Report 254

    ERIC Educational Resources Information Center

    Levine, Daniel H.; Bishai, Linda S.

    2010-01-01

    Between 2006 and 2010, the United States Institute of Peace developed several civic education programs for Iraq and Sudan as part of broader efforts to promote postconflict stability and development and help prevent a return to violence. This report describes those programs after first examining the conceptual bases for civic education and how…

  11. Examining the Contemporary Status of an Education System: The Case of the Republic of South Sudan

    ERIC Educational Resources Information Center

    Banraba, Boboya James Edimond

    2015-01-01

    This paper attempts to examine the contemporary status of an education system. The paper takes the case of the Republic of South Sudan. The key issues the paper will examine are the education enrollment and completion rates while paying particular attention to inequalities in both access and quality among racial or ethnic groups, males and…

  12. Population-Level Effect of Cholera Vaccine on Displaced Populations, South Sudan, 2014.

    PubMed

    Azman, Andrew S; Rumunu, John; Abubakar, Abdinasir; West, Haley; Ciglenecki, Iza; Helderman, Trina; Wamala, Joseph Francis; Vázquez, Olimpia de la Rosa; Perea, William; Sack, David A; Legros, Dominique; Martin, Stephen; Lessler, Justin; Luquero, Francisco J

    2016-06-01

    Following mass population displacements in South Sudan, preventive cholera vaccination campaigns were conducted in displaced persons camps before a 2014 cholera outbreak. We compare cholera transmission in vaccinated and unvaccinated areas and show vaccination likely halted transmission within vaccinated areas, illustrating the potential for oral cholera vaccine to stop cholera transmission in vulnerable populations. PMID:27192187

  13. Hyalomma ticks on northward migrating birds in southern Spain: Implications for the risk of entry of Crimean-Congo haemorrhagic fever virus to Great Britain.

    PubMed

    England, Marion E; Phipps, Paul; Medlock, Jolyon M; Atkinson, Peter M; Atkinson, Barry; Hewson, Roger; Gale, Paul

    2016-06-01

    Crimean-Congo haemorrhagic fever virus (CCHFV) is a zoonotic virus transmitted by Hyalomma ticks, the immature stages of which may be carried by migratory birds. In this study, a total of 12 Hyalomma ticks were recovered from five of 228 migratory birds trapped in Spring, 2012 in southern Spain along the East Atlantic flyway. All collected ticks tested negative for CCHFV. While most birds had zero Hyalomma ticks, two individuals had four and five ticks each and the statistical distribution of Hyalomma tick counts per bird is over-dispersed compared to the Poisson distribution, demonstrating the need for intensive sampling studies to avoid underestimating the total number of ticks. Rates of tick exchange on migratory birds during their northwards migration will affect the probability that a Hyalomma tick entering Great Britain is positive for CCHFV. Drawing on published data, evidence is presented that the latitude of a European country affects the probability of entry of Hyalomma ticks on wild birds. Further data on Hyalomma infestation rates and tick exchange rates are required along the East Atlantic flyway to further our understanding of the origin of Hyalomma ticks (i.e., Africa or southern Europe) and hence the probability of entry of CCHFV into GB. PMID:27232135

  14. Carbonate saturation state of surface waters in the Ross Sea and Southern Ocean: controls and implications for the onset of aragonite undersaturation

    NASA Astrophysics Data System (ADS)

    DeJong, H. B.; Dunbar, R. B.; Mucciarone, D.; Koweek, D. A.

    2015-12-01

    Predicting when surface waters of the Ross Sea and Southern Ocean will become undersaturated with respect to biogenic carbonate minerals is challenging in part due to the lack of baseline high-resolution carbon system data. Here we present ~ 1700 surface total alkalinity measurements from the Ross Sea and along a transect between the Ross Sea and southern Chile from the austral autumn (February-March 2013). We calculate the saturation state of aragonite (ΩAr) and calcite (Ω Ca) using measured total alkalinity and pCO2. In the Ross Sea and south of the Polar Front, variability in carbonate saturation state (Ω) is mainly driven by algal photosynthesis. Freshwater dilution and calcification have minimal influence on Ω variability. We estimate an early spring surface water ΩAr value of ~ 1.2 for the Ross Sea using a total alkalinity-salinity relationship and historical pCO2 measurements. Our results suggest that the Ross Sea is not likely to become undersaturated with respect to aragonite until the year 2070.

  15. Combined structural interventions for gender equality and livelihood security: a critical review of the evidence from southern and eastern Africa and the implications for young people

    PubMed Central

    Gibbs, Andrew; Willan, Samantha; Misselhorn, Alison; Mangoma, Jaqualine

    2012-01-01

    Background Young people in southern and eastern Africa remain disproportionately vulnerable to HIV with gender inequalities and livelihood insecurities being key drivers of this. Behavioural HIV prevention interventions have had weak outcomes and a new generation of structural interventions have emerged seeking to challenge the wider drivers of the HIV epidemic, including gender inequalities and livelihood insecurities. Methods We searched key academic data bases to identify interventions that simultaneously sought to strengthen people's livelihoods and transform gender relationships that had been evaluated in southern and eastern Africa. Our initial search identified 468 articles. We manually reviewed these and identified nine interventions that met our criteria for inclusion. Results We clustered the nine interventions into three groups: microfinance and gender empowerment interventions; supporting greater participation of women and girls in primary and secondary education; and gender empowerment and financial literacy interventions. We summarise the strengths and limitations of these interventions, with a particular focus on what lessons may be learnt for young people (18–24). Conclusions Our review identified three major lessons for structural interventions that sought to transform gender relationships and strengthen livelihoods: 1) interventions have a narrow conceptualisation of livelihoods, 2) there is limited involvement of men and boys in such interventions, 3) studies have typically been done in stable populations. We discuss what this means for future interventions that target young people through these methods. PMID:22713350

  16. Late Cretaceous protolith age and provenance of the Pelona and Orocopia Schists, southern California: Implications for evolution of the Cordilleran margin

    SciTech Connect

    Jacobson, C.E.; Barth, A.P.; Grove, M.

    2000-03-01

    The Pelona and Orocopia Schists are southern members of a eugeoclinal terrane that structurally underlies a large part of southwestern North America. Ion-microprobe U-Pb ages of >100 detrital zircons from three widely spaced samples of these two units indicate that deposition occurred after 70--80 Ma. Moreover, the distribution of zircon ages, including a significant peak centered ca. 1.7 Ga, implies a major contribution f detritus from the Mojave Desert and Transverse Ranges of southern California. Recrystallization of the schists at depths of 20--35 km occurred within 10--15 m.y. of deposition, which requires underthrusting at minimum rates of {approximately}4--12 mm/yr for reasonable thrust dips. Considering that similar processes formed the more northern Rand Schist at somewhat earlier times, results indicate a southward progression in timing of deformation for the schists' protoliths. This result is at odds with northward migration of deformation implied by the Baja British Columbia hypothesis. The age and provenance of the schist's protoliths are consistent with models that derive the schists from either the Franciscan Complex or Great Valley Group.

  17. Late Holocene Environmental Change at Amara West: A New Kingdom Town on the Desert Nile in Northern Sudan

    NASA Astrophysics Data System (ADS)

    Spencer, Neal; Woodward, Jamie; Macklin, Mark; Dalton, Matthew

    2014-05-01

    Amara West is a well-preserved town of the late New Kingdom downstream of Sai Island in Northern Sudan. The town has being identified as the seat of the pharaonic administration of Kush (Upper Nubia) in the Ramesside Period (c. 1306-1070 BC). This region fell under Egyptian control after about 1500 BC. The modern Nile (flowing eastwards in this reach) lies to the south of the town and a well preserved palaeochannel lies immediately to the north. Following the Egypt Exploration Society excavations of 1938-39 and 1947-48, it was argued that the ancient town was once located upon an island in the Nile. Renewed archaeological excavations allied to geomorphological work on the ancient river environment are attempting to establish the nature of the local and regional landscape before, during, and after the occupation of the town. This paper presents new OSL and radiocarbon dates on the sedimentary fill from the palaeochannel system to establish when the channel system ceased to flow on a permanent basis. Micromorphological work on the sedimentary records within the town provide additional insights into the nature of the local environment during the period of occupation. We discuss the implications of the new palaeoenvironmental data for our understanding of Amara West and we set out the wider significance of these new geoarchaeological data.

  18. Antibody Treatment of Ebola and Sudan Virus Infection via a Uniquely Exposed Epitope within the Glycoprotein Receptor-Binding Site.

    PubMed

    Howell, Katie A; Qiu, Xiangguo; Brannan, Jennifer M; Bryan, Christopher; Davidson, Edgar; Holtsberg, Frederick W; Wec, Anna Z; Shulenin, Sergey; Biggins, Julia E; Douglas, Robin; Enterlein, Sven G; Turner, Hannah L; Pallesen, Jesper; Murin, Charles D; He, Shihua; Kroeker, Andrea; Vu, Hong; Herbert, Andrew S; Fusco, Marnie L; Nyakatura, Elisabeth K; Lai, Jonathan R; Keck, Zhen-Yong; Foung, Steven K H; Saphire, Erica Ollmann; Zeitlin, Larry; Ward, Andrew B; Chandran, Kartik; Doranz, Benjamin J; Kobinger, Gary P; Dye, John M; Aman, M Javad

    2016-05-17

    Previous efforts to identify cross-neutralizing antibodies to the receptor-binding site (RBS) of ebolavirus glycoproteins have been unsuccessful, largely because the RBS is occluded on the viral surface. We report a monoclonal antibody (FVM04) that targets a uniquely exposed epitope within the RBS; cross-neutralizes Ebola (EBOV), Sudan (SUDV), and, to a lesser extent, Bundibugyo viruses; and shows protection against EBOV and SUDV in mice and guinea pigs. The antibody cocktail ZMapp™ is remarkably effective against EBOV (Zaire) but does not cross-neutralize other ebolaviruses. By replacing one of the ZMapp™ components with FVM04, we retained the anti-EBOV efficacy while extending the breadth of protection to SUDV, thereby generating a cross-protective antibody cocktail. In addition, we report several mutations at the base of the ebolavirus glycoprotein that enhance the binding of FVM04 and other cross-reactive antibodies. These findings have important implications for pan-ebolavirus vaccine development and defining broadly protective antibody cocktails. PMID:27160900

  19. Disability associated with exposure to traumatic events: results from a cross-sectional community survey in South Sudan

    PubMed Central

    2013-01-01

    Background There is a general lack of knowledge regarding disability and especially factors that are associated with disability in low-income countries. We aimed to study the overall and gender-specific prevalence of disability, and the association between exposure to traumatic events and disability in a post-conflict setting. Methods We conducted a cross-sectional community based study of four Greater Bahr el Ghazal States, South Sudan (n = 1200). The Harvard Trauma Questionnaire (HTQ) was applied to investigate exposure to trauma events. Disability was measured using the Washington Group Short Measurement Set on Disability, which is an activity-based scale derived from the WHO’s International Classification of Disability, Functioning and Health. Results The estimated prevalence of disability (with severe difficulty) was 3.6% and 13.4% for disability with moderate difficulties. No gender differences were found in disability prevalence. Almost all participants reported exposure to at least one war-related traumatic event. The result of a hierarchical regression analysis showed that, for both men and women, exposure to traumatic events, older age and living in a polygamous marriage increased the likelihood of having a disability. Conclusions The finding of association between traumatic experience and disability underlines the precariousness of the human rights situation for individuals with disability in low-income countries. It also has possible implications for the construction of disability services and for the provision of health services to individuals exposed to traumatic events. PMID:23672785

  20. Petrogenesis of Cretaceous adakite-like intrusions of the Gangdese Plutonic Belt, southern Tibet: Implications for mid-ocean ridge subduction and crustal growth

    NASA Astrophysics Data System (ADS)

    Zheng, Yuan-chuan; Hou, Zeng-qian; Gong, Ying-li; Liang, Wei; Sun, Qing-Zhong; Zhang, Song; Fu, Qiang; Huang, Ke-Xian; Li, Qiu-Yun; Li, Wei

    2014-03-01

    We have conducted a whole-rock geochemical, U-Pb zircon geochronological, and in situ zircon Hf-O isotopic compositional study of rocks in southern Tibet from the Langxian igneous suite (including a lamprophyre dyke, mafic enclaves, a granodiorite, and a two-mica granite) and the Nuri igneous suite (a quartz-diorite). U-Pb zircon dating indicates that the timing of crystallization of the mafic enclaves and host granodiorite of the Langxian suite are ca. 105 Ma and 102 Ma, respectively, that the Langxian lamprophyre dyke and the two-mica granite were emplaced at ca. 96 Ma and 80-76 Ma, respectively, and that the Nuri quartz-diorite was emplaced at ca. 95 Ma. With the exception of the lamprophyre dyke and mafic enclaves in the Langxian area, felsic rocks from the Langxian and Nuri igneous suites all show signs of a geochemical affinity with adakite-like rocks. The high Mg-numbers, high abundance of compatible elements, high ɛNd(t) (2.7 and 2.8) and δ18O (8.9 and 9.2‰) values, elevated zircon ɛHf(t) (11.0-17.0) values, and low 87Sr/86Sr(i) ratios (0.7040), collectively indicate that the Nuri adakite-like quartz-diorite was derived from partial melting of the low temperature altered Neo-Tethyan oceanic crust, and that these dioritic magmas subsequently interacted with peridotite as they rose upwards through the overlying mantle wedge. The observation of identical differentiation trends, similar whole-rock Sr-Nd and zircon Hf isotopic compositions, and consistently low (Dy/Yb)N ratios among the Langxian igneous suite rocks, indicates that the adakite-like granodiorite was produced by low-pressure fractional crystallization of precursor magmas now represented by the (relict) mafic enclaves. However, relatively high Al2O3 contents, low MgO, Cr and Ni contents, and low (La/Yb)N and (Dy/Yb)N values indicate that the two-mica granite was derived from partial melting of the southern Tibetan mafic lower crust in the absence of garnet, while isotopic data suggest that at

  1. Hepatitis C Virus Epidemiology in Djibouti, Somalia, Sudan, and Yemen: Systematic Review and Meta-Analysis

    PubMed Central

    Chaabna, Karima; Kouyoumjian, Silva P.; Abu-Raddad, Laith J.

    2016-01-01

    Objectives To characterize hepatitis C virus (HCV) epidemiology and assess country-specific population-level HCV prevalence in four countries in the Middle East and North Africa (MENA) region: Djibouti, Somalia, Sudan, and Yemen. Methods Reports of HCV prevalence were systematically reviewed as per PRISMA guidelines. Pooled HCV prevalence estimates in different risk populations were conducted when the number of measures per risk category was at least five. Results We identified 101 prevalence estimates. Pooled HCV antibody prevalence in the general population in Somalia, Sudan and Yemen was 0.9% (95% confidence interval [95%CI]: 0.3%–1.9%), 1.0% (95%CI: 0.3%–1.9%) and 1.9% (95%CI: 1.4%–2.6%), respectively. The only general population study from Djibouti reported a prevalence of 0.3% (CI: 0.2%–0.4%) in blood donors. In high-risk populations (e.g., haemodialysis and haemophilia patients), pooled HCV prevalence was 17.3% (95%CI: 8.6%–28.2%) in Sudan. In Yemen, three studies of haemodialysis patients reported HCV prevalence between 40.0%-62.7%. In intermediate-risk populations (e.g.. healthcare workers, in patients and men who have sex with men), pooled HCV prevalence was 1.7% (95%CI: 0.0%–4.9%) in Somalia and 0.6% (95%CI: 0.4%–0.8%) in Sudan. Conclusion National HCV prevalence in Yemen appears to be higher than in Djibouti, Somalia, and Sudan as well as most other MENA countries; but otherwise prevalence levels in this subregion are comparable to global levels. The high HCV prevalence in patients who have undergone clinical care appears to reflect ongoing transmission in clinical settings. HCV prevalence in people who inject drugs remains unknown. PMID:26900839

  2. Malaria control in South Sudan, 2006–2013: strategies, progress and challenges

    PubMed Central

    2013-01-01

    Background South Sudan has borne the brunt of years of chronic warfare and probably has the highest malaria burden in sub-Saharan Africa. However, effective malaria control in post-conflict settings is hampered by a multiplicity of challenges. This manuscript reports on the strategies, progress and challenges of malaria control in South Sudan and serves as an example epitome for programmes operating in similar environments and provides a window for leveraging resources. Case description To evaluate progress and challenges of the national malaria control programme an in-depth appraisal was undertaken according to the World Health Organization standard procedures for malaria programme performance review. Methodical analysis of published and unpublished documents on malaria control in South Sudan was conducted. To ensure completeness, findings of internal thematic desk assessments were triangulated in the field and updated by external review teams. Discussion and evaluation South Sudan has strived to make progress in implementing the WHO recommended malaria control interventions as set out in the 2006–2013 National Malaria Strategic Plan. The country has faced enormous programmatic constraints including infrastructure, human and financial resource and a weak health system compounded by an increasing number of refugees, returnees and internally displaced people. The findings present a platform on which to tailor an evidence-based 2014–2018 national malaria strategic plan for the country and a unique opportunity for providing a model for countries in a post-conflict situation. Conclusions The prospects for effective malaria control and elimination are huge in South Sudan. Nevertheless, strengthened coordination, infrastructure and human resource capacity, monitoring and evaluation are required. To achieve all this, allocation of adequate local funding would be critical. PMID:24160336

  3. Henry Solomon Wellcome: A philanthropist and a pioneer sponsor of medical research in the Sudan

    PubMed Central

    Adeel, Ahmed Awad A.

    2013-01-01

    Henry Solomon Wellcome, the famous drug manufacturer had a fascinating association with the Sudan. Besides supporting tropical medicine research in this country, he established an extensive project in the Sudan that aimed at combining archeological excavations, philanthropy and social reform. This article is an archives-based account on this side of Wellcome’s association with the Sudan. The article starts with Wellcome’s early years in the American Midwest and the evolution of his career and his rise as a world-renowned drug manufacturer. After the battle of Omdurman, Wellcome visited Sudan in 1900 – 1901 where he offered to support the establishment of the research laboratories which later came to be known as the Wellcome Tropical Research Laboratories in Khartoum. He then became directly involved in the planning and running of extensive archeological excavations in the central Sudan. This project served as a field in which Wellcome found an outlet for his philanthropy. More than 4000 labourers were employed in Jebel Moya. Professional archeologists and anatomists were recruited by Wellcome to supervise the work, and all the requirements in terms of equipment were catered for. Wellcome devised a Savings Bank System whereby part of the earnings of each labourer were saved to him till the end of the season. He also introduced one of his innovations: aerial photography using box kite which was used for the first time in archeology. Wellcome made it a rule that no applicant should be turned away. The Camp Commandant had to find suitable work for each applicant, including the handicapped who were assigned to appropriate jobs like mending baskets or cutting grass for building huts. Wellcome’s welfare work had a significant impact on the local inhabitants of Jebel Moya. Henry Solomon Wellcome, 1906. Oil painting by Hugh Goldwin Riviere. Credit: Wellcome Library PMID:27493379

  4. Differential gene expression in Staphylococcus aureus exposed to Orange II and Sudan III azo dyes.

    PubMed

    Pan, Hongmiao; Xu, Joshua; Kweon, Oh-Gew; Zou, Wen; Feng, Jinhui; He, Gui-Xin; Cerniglia, Carl E; Chen, Huizhong

    2015-05-01

    We previously demonstrated the effects of azo dyes and their reduction metabolites on bacterial cell growth and cell viability. In this report, the effects of Orange II and Sudan III on gene expression profiling in Staphylococcus aureus ATCC BAA 1556 were analyzed using microarray and quantitative RT-PCR technology. Upon exposure to 6 μg/ml Orange II for 18 h, 21 genes were found to be differently expressed. Among them, 8 and 13 genes were up- and down-regulated, respectively. Most proteins encoded by these differentially expressed genes involve stress response caused by drug metabolism, oxidation, and alkaline shock indicating that S. aureus could adapt to Orange II exposure through a balance between up and down regulated gene expression. Whereas, after exposure to 6 μg/ml Sudan III for 18 h, 57 genes were differentially expressed. In which, 51 genes were up-regulated and 6 were down-regulated. Most proteins encoded by these differentially expressed genes involve in cell wall/membrane biogenesis and biosynthesis, nutrient uptake, transport and metabolite, and stress response, suggesting that Sudan III damages the bacterial cell wall or/and membrane due to binding of the dye. Further analysis indicated that all differentially expressed genes encoded membrane proteins were up-regulated and most of them serve as transporters. The result suggested that these genes might contribute to survival, persistence and growth in the presence of Sudan III. Only one gene msrA, which plays an important role in oxidative stress resistance, was found to be down-regulated after exposure to both Orange II and Sudan III. The present results suggested that both these two azo dyes can cause stress in S. aureus and the response of the bacterium to the stress is mainly related to characteristics of the azo dyes. PMID:25720844

  5. Petroleum maturation modelling, Abu Gabra Sharaf area, Muglad Basin, Sudan

    NASA Astrophysics Data System (ADS)

    Mohamed, Abdalla Y.; Pearson, Michael J.; Ashcroft, William A.; Whiteman, A. J.

    2002-08-01

    Structural and maturation studies in the northwest of the Muglad Basin, Sudan showed a thick sedimentary section up to 9000 m in the deep sub-basins and an average of about 6000 m in the Sharaf-Abu Gabra Ridge. The isopach map of the Lower Cretaceous Abu Gabra-Sharaf formations, which contain source rocks, showed a thickness of sedimentary section between 2000 and 5000 m. The burial history showed high subsidence rates during the first rifting phase with relatively low subsidence rates during the following two phases in this part of the basin. Significant erosion of the sedimentary section occurred in the ridge area during Miocene and Cenomanian-Albian times. The geothermal gradients in the modelled wells range between 18 and 27.5 °C/km corresponding to the relatively wide range of present day heat flow of between 37 and 63 mW/m 2, averaging 50 mW/m 2. Heat flow history curves consistent with vitrinite reflectance data were adopted with elevated high heat flow (75 mW/m 2) during the first rifting phase followed by minor peaks (average 60 mW/m 2) during the second and the third rifting phases. Application of a kinetic vitrinite maturation model resulted in a present day oil window between 2000 and 4500 m. The source rock of the Abu Gabra (AG) and Sharaf (SH) formations, which has an average total organic carbon of 1.0% and hydrogen index (HI) of 280, was modelled for hydrocarbon generation. The section was divided into four layers; AG-1 (Albian), AG-2 (Aptian), SH-1 (Barremian) and SH-2 (Neocomian). Conditions for hydrocarbon generation are present throughout the Sharaf formation and in AG-2. The generation model suggests an average generation amount of 4 mgHC/g rock in the lower three modelled layers with a timing range between 120 Ma and the present. Total calculated oil volume is about 370 US billion bbls and the expected volume expelled and migrated (40%) is 150 US billion bbls. The total gas expelled and migrated (90%) is 1600 US trillion cu ft. Retention of

  6. Magnetic Prospection at the Archaeological Site of Jebel Barkal, Sudan

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed A. Mohamed; Goldmann, Thomas; Wolf, Pawel; Wützler, Ronny; Goldmann, Lukas; Hobbs, Richard; Kendall, Timothy

    2010-05-01

    One of most important archaeological sites in northern Sudan is Jebel Barkal, an isolated sandstone butte, which became the chief cult center of the ancient Sudanese kingdom of Kush (ca. 800 BC-400 AD). Located on the western edge of the modern town of Karima, just downstream from the Nile's fourth cataract, Jebel Barkal is the site of numerous ruined palaces, temples, and pyramids. In 2006 and 2007, we carried out a magnetic survey of about 3.5 hectares of the temple area using an Overhauser magnetometer GSM 19. Our objective was to prospect some of the unexcavated areas of the site to try to image the sub-soil remains, and our resulting map clearly shows a number of magnetic anomalies of mud-brick, fired brick and stone-block walls belonging to different ancient buildings. Our initial magnetic results successfully revealed one corner of the wall of the early Meroitic palace B 100, which had been "lost" after its excavation in 1916, since it buried by later excavation debris before it had been precisely located on any site map. Prospection in the same area also revealed other (earlier?) massive mud walls of unknown function and character. A second area we chose for examination was that in front of the Great Amun Temple (B 500). Here we found two or three small rectangular anomalies that suggested a series of small chapels built at right angles to the paved way leading into the Great Temple; the layout was identical to chapels in front of the Great Amun Temple at Meroe. Another magnetic anomaly in front of B 500 seemed to be a predictable type of stepped podium, well-known from other Kushite temples. A third area we chose to examine was that northeast of B 500. Here we found the clear outline of a multi-chambered building (B 1700) parallel to the Great Temple, which appeared to have all the characteristics of a smaller temple fronted by a pylon. Far less clear were the complex magnetic anomalies we found northeast of B 1700. These appeared to belong to a series of

  7. Women's income generation activities in Merowe Province, Northern State, Sudan.

    PubMed

    Pitamber, S; Osama, S

    1994-06-01

    Merowe province in rural northern Sudan has been divided into three local government council areas: Merowe, Karima, and Ed Debba. A government program was instituted to increase the welfare of residents and food production. A baseline survey of 490 respondents was conducted in order to ascertain how illiterate women viewed development in the area and to provide useful information for program design and implementation. Women from 24 villages were administered questionnaires, observed in their daily activities, and engaged in discussion in a local meeting place. Discussions were also held with members of the local Popular Committee. Demographic information was very sketchy about age, and 48% had no formal education in writing and reading. General reading and writing skills of the remainder were very poor. There were 500 female children and 502 male children, and the sex ratio varied among the 3 council areas. 52% were married and 14% were divorced or widowed and living with relatives. The average monthly income was from Ls. 700 to Ls. 3000 based on reports from only 59.3% of respondents. Most of the women had skills in food processing and 25.7% were skilled in handicrafts. Water was obtained primarily from local wells and not decontaminated before use. Pit latrines were the standard. One bathing facility was available in the compound for the entire council area. Health units were either in each village or within 20-30 minutes walk. Child mortality was 4.3% in Merowe province. 77 children 0-5 years old died out of a total of 1002 live births. Life expectancy was 41-50 years for women and 61-70 years for men. Cleanliness and healthful eating were observed. 58% owned no land; plots were under 5 feddans and usually half a feddan. 92.1% had no bank account and 90% had no experience with loans. 70.2% were indifferent about involvement in an income generation program. 26% were interested in part-time participation. Only 3.9% desired full-time participation. 8.6% said they

  8. On the development of Antarctic katabatic winds and their impact on ocean and ice processes in the coastal Southern Ocean with implications for primary productivity

    NASA Astrophysics Data System (ADS)

    Goodrick, Scott Lawrence

    1997-10-01

    As a first step toward improving the present understanding of the physics that control air-sea CO2 exchange in the Southern Ocean, a coupled mesoscale atmosphere-ocean-sea ice model is described and used to examine the interaction of Antarctic katabatic winds with coastal ocean and sea ice processes. These winds are a dominant factor in shaping the climatology of Antarctica, particularly during the austral winter. Simulations are presented for winter and early spring conditions. For the spring case a simple primary productivity model is used to examine the early stages of phytoplankton bloom development. Latent heat polynyas are a common feature along the Antarctic coast. These ice-free regions are maintained by a balance between wind driven ice divergence and ice production. For the winter simulation the coupled model creates an initial polynya that closes after 4 days of simulation. The closing of the polynya is linked to the adjustment of the katabatic winds to the alongshore direction which forces shoreward Ekman transport of the sea ice, closing the polynya. Seasonal variations in the magnitude of the katabatic flows are linked to variations in the strength of the East Wind Drift. During the winter, the offshore directed katabtic winds adjust geostrophically, contributing to the strong polar easterlies of high southern latitudes. Shoreward Ekman transport associated with these easterlies supports a barotropic coastal current, the East Wind Drift. During spring the adjustment process is interrupted by the diurnal cycle, weakening the Ekman transport and the coastal current. Phytoplankton blooms in the Southern Ocean are typically linked to the retreat of the seasonal ice cover. As the sea ice melts the associated input of fresh water stabilizes the surface layer of the ocean limiting the depth of turbulent mixing. In early spring, sea ice coverage, incoming solar irradiance and wind stress are shown to be the major factors contributing to early bloom

  9. Co-diagenesis of iron and phosphorus in hydrothermal sediments from the southern East Pacific Rise: Implications for the evaluation of paleoseawater phosphate concentrations

    NASA Astrophysics Data System (ADS)

    Poulton, Simon W.; Canfield, Donald E.

    2006-12-01

    We present a detailed study of the co-diagenesis of Fe and P in hydrothermal plume fallout sediments from ˜19°S on the southern East Pacific Rise. Three distal sediment cores from 340-1130 km from the ridge crest, collected during DSDP Leg 92, were analysed for solid phase Fe and P associations using sequential chemical extraction techniques. The sediments at all sites are enriched in hydrothermal Fe (oxyhydr)oxides, but during diagenesis a large proportion of the primary ferrihydrite precipitates are transformed to the more stable mineral form of goethite and to a lesser extent to clay minerals, resulting in the release to solution of scavenged P. However, a significant proportion of this P is retained within the sediment, by incorporation into secondary goethite, by precipitation as authigenic apatite, and by readsorption to Fe (oxyhydr)oxides. Molar P/Fe ratios for these sediments are significantly lower than those measured in plume particles from more northern localities along the southern East Pacific Rise, and show a distinct downcore decrease to a depth of ˜12 m. Molar P/Fe ratios are then relatively constant to a depth of ˜35 m. The Fe and P speciation data indicate that diagenetic modification of the sediments is largely complete by a depth of 2.5 m, and thus depth trends in molar P/Fe ratios can not solely be explained by losses of P from the sediment by diffusion to the overlying water column during early diagenesis. Instead, these sediments are likely recording changes in dissolved P concentrations off the SEPR, possibly as a result of redistribution of nutrients in response to changes in oceanic circulation over the last 10 million years. Furthermore, the relatively low molar P/Fe ratios observed throughout these sediments are not necessarily solely due to losses of scavenged P by diffusion to the overlying water column during diagenesis, but may also reflect post-depositional oxidation of pyrite originating from the volatile-rich vents of the

  10. Kinematic Evolution of fold-and-thrust Belts in the Yubei Area: Implications for the Tectonic Events of Ordovician at the Southern Tarim Basin

    NASA Astrophysics Data System (ADS)

    Zhang, Y.

    2015-12-01

    As a response to tecto-orogenic processes of the South Altun and the West Kunlun (Monlar P, 1975; He Bizhu, 2011), early Paleozoic tectonic evolution of the southern Tarim craton was distinctively one of the extensions and was followed by compression (Morris W.Leighton, 1990; Gao Zhiqian, 2015). From the late Ordovician, the Yubei area developed distinctively NE-SW trending fold-and-thrust belts in rows which were eroded and deformed through multiphase tectonic movement (Dengfa He, 2007), with similarities and dissimilarities between each other rows in many aspects, at the Southern Tarim inner basin (Fig. 1). The northern of Hetian paleo-uplift and the northwestern of NE-trending folds zone on Caledonian in Tangguzibasi depression should be favorable to the potential exploration area for the first large-scale period of hydrocarbon migration and accumulation (Brown LF, 1979). In this contribution, based on geophysical log, core and 2D/3D seismic data, we constructed its tectonic geometry morphology, controlled by detailed chronostratigraphic framework. According to the fault-related fold theory, rows of asymmetric fault-propagation folds grew in the Yubei area during the late Caledonian period, with the evidence of interpreted growth strata from the high resolution 3D seismic data (Suppe J et al., 1990). That intercontinental tecto-orogenic events from southern Tarim basin, leading to the transformation of its margins, affected inner basin at that time, modified the basin into the Tarim metacraton (Jean-Paul Liégeois, 2013; Zieglar P.A., 1998). Correlating the four tectonic groups of the identified with the axis variation of strata and fold amplitude distribution showed that fault evolution progressed in several superimposed stages: Precambrian, late Ordovician to early Carboniferous (Zhao Zongju, 2009), Carboniferous to Permian, Cenozoic. Analyzing the sedimentary development and structure evolution the tectonic paleo-geographic setting is reconstructed, providing

  11. Field geology, geochronology and geochemistry of mafic-ultramafic rocks from Alxa, China: Implications for Late Permian accretionary tectonics in the southern Altaids

    NASA Astrophysics Data System (ADS)

    Feng, Jianyun; Xiao, Wenjiao; Windley, Brian; Han, Chunming; Wan, Bo; Zhang, Ji'en; Ao, Songjian; Zhang, Zhiyong; Lin, Lina

    2013-12-01

    The time of termination of orogenesis for the southern Altaids has been controversial. Systematic investigations of field geology, geochronology and geochemistry on newly discriminated mafic-ultramafic rocks from northern Alxa in the southern Altaids were conducted to address the termination problem. The mafic-ultramafic rocks are located in the Bijiertai, Honggueryulin, and Qinggele areas, stretching from west to east for about 100 km. All rocks occur high-grade gneisses as tectonic lenses that are composed of peridotite, pyroxenite, gabbro, and serpentinite, most of which have undergone pronounced alteration, i.e., serpentinization and chloritization. Geochemically, the rocks are characterized by uniform compositional trends, i.e., with low SiO2-contents (42.51-52.21 wt.%) and alkalinity (Na2O + K2O) (0.01-5.45 wt.%, mostly less than 0.8 wt.%), and enrichments in MgO (7.37-43.36 wt.%), with Mg# = 52.75-91.87. As the rocks have been strongly altered and have a wide range of loss-on-ignition (LOI: 0.44-14.07 wt.%) values, they may have been subjected to considerable alteration by either seawater or metamorphic fluids. The REE and trace element patterns show a relatively fractionated trend with LILE enrichment and HFSE depletion, similar to that of T-MORB between N-MORB and E-MORB, indicating that the parental melt resulted from the partial melting of oceanic lithospheric mantle overprinted by fluid alteration of island-arc origin. The ultramafic rocks are relics derived from the magma after a large degree of partial melting of oceanic lithospheric mantle with superposed island arc processes under the influence of mid-ocean-ridge magmatism. LA-ICP MS U-Pb zircon ages of gabbros from three spots are 274 ± 3 Ma (MSWD = 0.35), 306 ± 3 Ma (MSWD = 0.49), 262 ± 5 Ma (MSWD = 1.2), respectively, representing the formation ages of the mafic-ultramafic rocks. Therefore, considering other previously published data, we suggest that the mafic-ultramafic rocks were products of

  12. Field geology, geochronology and geochemistry of mafic-ultramafic rocks from Alxa, China: Implications for Late Permian accretionary tectonics in the southern Altaids

    NASA Astrophysics Data System (ADS)

    Jianyun, Feng; Wenjiao, Xiao

    2013-04-01

    The termination of orogenesis for the southern Altaids has been controversial. Systematical investigations of field geology, geochronology and geochemistry on mafic-ultramafic rocks from the northern Alxa of the southern Altaids were conducted to address the termination controversy. The newly discriminated mafic-ultramafic rocks belt is located at Bijiertai, Honggueryulin, and Qinggele areas, stretching from west to east for about 100 km in length. All of the three rock associations contact tectonically with the adjacent metamorphic and deformed Precambrian rocks as tectonic blocks or lenses, and are composed of peridotite, pyroxenite, gabbro, and serpentinite, most of which have subjected to pronounced alteration, i.e., serpentinization and chloritization. Geochemically, the rocks are characterized by a uniform trend of compositional distribution, e.g., with low SiO2-contents (42.51-52.21 wt.%) and alkalinity (Na2O+K2O) (0.01-5.45 wt.%, mostly less than 0.8 wt.%), and enriched in MgO (7.37-43.36 wt.%), with Mg# = 52.75-91.87. As the rocks have had strong alteration and have a wide range of loss-on-ignition (LOI: 0.44-14.07 wt.%), the rocks may be subjected to considerable alteration by either sea-water or metamorphic fluid. The REE and trace element patterns for the rocks show a relatively fractionated trend with LILE enrichment and HFSE depletion, similar to that of T-MORB between N-MORB and E-MORB, indicating that the parental melt resulted from the partial melting of oceanic lithospheric mantle overprinted by fluid alteration of island-arc subsequently. The ultramafic rocks are relics derived from the magma after large degree of partial melting of the oceanic lithospheric mantle with overprinted by island-arc processes under the influence of mid-ocean-ridge magmatism. LA - ICP MS U - Pb zircon ages of gabbros from the three spots are 274 ± 3 Ma (MSWD = 0.35), 306 ± 3 Ma (MSWD = 0.49), 262 ± 5 Ma (MSWD = 1.2), respectively, representing the formation ages of

  13. Uranium series disequilibria in ground waters from a fractured bedrock aquifer (Morungaba Granitoids--Southern Brazil): implications to the hydrochemical behavior of dissolved U and Ra.

    PubMed

    Reyes, Erika; Marques, Leila S

    2008-10-01

    Activity concentrations of dissolved (234)U, (238)U, (226)Ra and (228)Ra were determined in ground waters from two deep wells drilled in Morungaba Granitoids (Southern Brazil). Sampling was done monthly for little longer than 1 year. Significant disequilibrium between (238)U, (234)U and (226)Ra were observed in all samples. The variation of (238)U and (234)U activity concentrations and (234)U/(238)U activity ratios is related to seasonal changes. Although the distance between the two wells is short (about 900 m), systematic differences of activity concentrations of U isotopes, as well as of (234)U/(238)U, (226)Ra/(234)U and (228)Ra/(226)Ra activity ratios were noticed, indicating distinct host rock-water interactions. Slightly acidic ground water percolation through heterogeneous host rock, associated with different recharge processes, may explain uranium and radium isotope behavior. PMID:18514535

  14. A New Estimate for Total Offset on the Southern San Andreas Fault: Implications for Cumulative Plate Boundary Shear in the Northern Gulf of California

    NASA Astrophysics Data System (ADS)

    Darin, M. H.; Dorsey, R. J.

    2012-12-01

    Development of a consistent and balanced tectonic reconstruction for the late Cenozoic San Andreas fault (SAF) in southern California has been hindered for decades by incompatible estimates of total dextral offset based on different geologic cross-fault markers. The older estimate of 240-270 km is based on offset fluvial conglomerates of the middle Miocene Mint Canyon and Caliente Formations west of the SAF from their presumed source area in the northern Chocolate Mountains NE of the SAF (Ehlig et al., 1975; Ehlert, 2003). The second widely cited offset marker is a distinctive Triassic megaporphyritic monzogranite that has been offset 160 ± 10 km between Liebre Mountain west of the SAF and the San Bernadino Mountains (Matti and Morton, 1993). In this analysis we use existing paleocurrent data and late Miocene clockwise rotation in the eastern Transverse Ranges (ETR) to re-assess the orientation of the piercing line used in the 240 km-correlation, and present a palinspastic reconstruction that satisfies all existing geologic constraints. Our reconstruction of the Mint Canyon piercing line reduces the original estimate of 240-270 km to 195 ± 15 km of cumulative right-lateral slip on the southern SAF (sensu stricto), which is consistent with other published estimates of 185 ± 20 km based on correlative basement terranes in the Salton Trough region. Our estimate of ~195 km is consistent with the lower estimate of ~160 km on the Mojave segment because transform-parallel extension along the southwestern boundary of the ETR during transrotation produces ~25-40 km of displacement that does not affect offset markers of the Liebre/San Bernadino correlation located northwest of the ETR rotating domain. Reconciliation of these disparate estimates places an important new constraint on the total plate boundary shear that is likely accommodated in the adjacent northern Gulf of California. Global plate circuit models require ~650 km of cumulative Pacific-North America (PAC

  15. Crustal rheology of the Santorini-Amorgos zone: Implications for the nucleation depth and rupture extent of the 9 July 1956 Amorgos earthquake, southern Aegean

    NASA Astrophysics Data System (ADS)

    Konstantinou, K. I.

    2010-12-01

    The 9 July 1956 Amorgos earthquake (Mw 7.6) was the largest event that hit Greece during the last century followed by a tsunami that inundated the coastal areas of the southern Aegean. This study investigates the rheological properties of the 1956 rupture zone between Amorgos and Santorini islands, in an effort to place some constraints on the nucleation depth and rupture extent of this large event. The seismic velocities inferred from tomographic and surface wave dispersion studies of the area are first correlated with laboratory determined velocities of known rock types. It is found that the lithosphere in the southern Aegean can be approximated by three layers representing the upper/lower crust and upper mantle consisting of quartzite, diabase and peridotite, respectively. Geotherms are calculated by using an analytical solution to the one-dimensional heat conduction equation, while Yield Strength Envelopes (YSEs) are produced after assuming laboratory estimated parameters of brittle and ductile deformation for each rock type. The depth frequency of earthquakes in the area, as well as other independent observations favour the YSE calculated for a wet upper crust/upper mantle, a dry lower crust and a geotherm corresponding to a surface heat flow of 62 mW m -2. In this YSE, the upper mantle exhibits maximum strength at 33 km becoming more ductile at greater depths. The lower crust retains significant strength and therefore cannot flow as it did during the early stages of extension, but it is relatively weaker than the upper mantle confirming the 'jelly sandwich' model previously proposed for the continental lithosphere. The downdip rupture width of the Amorgos event can be estimated from empirical relationships to be 26 km which means that its rupture may have extended from the depth of peak strength in the upper mantle (33 km) to 7 km upwards. Such a scenario agrees well with recent modelling results indicating that the Amorgos tsunami was probably caused by

  16. Late Carboniferous adakitic granodiorites in the Qiongkusitai area, western Tianshan, NW China: Implications for partial melting of lower crust in the southern Central Asian Orogenic Belt

    NASA Astrophysics Data System (ADS)

    Yin, Jiyuan; Chen, Wen; Xiao, Wenjiao; Yuan, Chao; Long, Xiaoping; Cai, Keda; Zhang, Bin

    2016-07-01

    Carboniferous granitic rocks are wide spread in the western Tianshan, but their tectonic contexts remain controversial. We present zircon U-Pb age, major element, trace element, and in situ zircon Hf isotopic data for the Qiongkusitai granodiorites from the southern part of the Yili block in the western Tianshan. The granodiorites were emplaced in the Late Carboniferous (ca. 314 Ma) and are characterized by high SiO2 (62.1-65.7 wt.%), high Sr (376-485 ppm), low Y (13.7-17.7 ppm) and low Yb (1.34-1.81 ppm) with Sr/Y ratios of 23-34. Such characteristics imply adakitic affinities. Their low concentrations of Cr (3.85-6.75 ppm), Co (7.63-10.7 ppm) and Ni (2.94-6.80 ppm) suggest little, if any, interaction with a mantle source. Compared to the thickened lower crustal-derived adakitic rocks, the relatively low Nb/Ta ratios of the Qiongkusitai adakitic granodiorites indicate that they were probably generated by partial melting of amphibolite facies rocks, but not eclogite facies rocks. The Qiongkusitai adakitic granodiorites have positive zircon εHf(t) values of +0.7 to +5.1 and TDM2 of 1.28-1.68 Ga, and they are interpreted as being derived from remelting of amphibolite facies Mesoproterozoic basement with an input of juvenile material. Late Carboniferous magmatism in the western Tianshan was possibly triggered by asthenospheric upwelling as a result of the roll-back of the subducted southern Tianshan oceanic lithosphere.

  17. New [sup 40]Ar/[sup 39]Ar mica ages from eastern New Hampshire and southern Maine: Implications for the exhumation history of the region

    SciTech Connect

    Lux, D.R.; West, D.P. Jr. . Dept. of Geological Science)

    1993-03-01

    It has long been recognized that micas from the high-grade metamorphic terrane of Maine and New Hampshire have anomalously young K-Ar ages. Furthermore, ages show systematic spatial patterns. Samples from western New Hampshire are youngest and become progressively older towards the east. In the Kearsarge-Central Maine Synclinorium (KCMS) of western Maine, ages are oldest along the northern terminus of high grade metamorphism and become progressively younger towards the southwest. In order to understand this peculiar relationship, micas from 20 sites in eastern New Hampshire and southern Maine were dated by the [sup 40]Ar/[sup 39]Ar method. The following relationships are observed: (1) Micas from the KCMS of southern New Hampshire have Permo-Carboniferous ages and coexisting micas are highly discordant, (2) micas from within or very near the Massabesic Gneiss Complex have young ages ([approximately]240--250 Ma) and show little to no discordance, (3) with one exception, micas from south of the Sebago batholith in Maine are also young ([approximately]240--250 Ma) and show little to no discordance. North of the Sebago batholith the transition to older micas is gradual. Mica ages from the Massabesic Gneiss Complex are younger than in surrounding regions and the transition to older ages roughly coincides with the Campbell Hill and Flint Hill faults. Outside the zone of young micas, cooling curves are concave upward for the same temperature interval. The young micas are concordant indicating rapid cooling but they are [approximately]40 Ma younger than the time of Late Paleozoic metamorphism. Therefore the young ages cannot be explained by rapid post-metamorphic cooling. The authors believe the accelerated cooling is the result of regional tectonic exhumation related to the earliest stages of rifting associated with opening of the Atlantic.

  18. Petrogenesis of early Jurassic basalts in southern Jiangxi Province, South China: Implications for the thermal state of the Mesozoic mantle beneath South China

    NASA Astrophysics Data System (ADS)

    Cen, Tao; Li, Wu-xian; Wang, Xuan-ce; Pang, Chong-jin; Li, Zheng-xiang; Xing, Guang-fu; Zhao, Xi-lin; Tao, Jihua

    2016-07-01

    Early Jurassic bimodal volcanic and intrusive rocks in southern South China show distinct associations and distribution patterns in comparison with those of the Middle Jurassic and Cretaceous rocks in the area. It is widely accepted that these rocks formed in an extensional setting, although the timing of the onset and the tectonic driver for extension are debated. Here, we present systematic LA-ICP-MS zircon U-Pb ages, whole-rock geochemistry and Sr-Nd isotope data for bimodal volcanic rocks from the Changpu Formation in the Changpu-Baimianshi and Dongkeng-Linjiang basins in southern Jiangxi Province, South China. Zircon U-Pb ages indicate that the bimodal volcanic rocks erupted at ca. 190 Ma, contemporaneous with the Fankeng basalts (~ 183 Ma). A compilation of geochronological results demonstrates that basin-scale basaltic eruptions occurred during the Early Jurassic within a relatively short interval (< 5 Ma). These Early Jurassic basalts have tholeiitic compositions and OIB-like trace element distribution patterns. Geochemical analyses show that the basalts were derived from depleted asthenospheric mantle, dominated by a volatile-free peridotite source. The calculated primary melt compositions suggest that the basalts formed at 1.9-2.1 GPa, with melting temperatures of 1378 °C-1405 °C and a mantle potential temperature (TP) ranging from 1383 °C to 1407 °C. The temperature range is somewhat hotter than normal mid-ocean-basalt (MORB) mantle but similar to an intra-plate continental mantle setting, such as the Basin and Range Province in western North America. This study provides an important constraint on the Early Jurassic mantle thermal state beneath South China.

  19. Nd- and Sr-isotopic compositions of lavas from the northern Mariana and southern Volcano arcs: implications for the origin of island arc melts

    NASA Astrophysics Data System (ADS)

    Lin, P. N.; Stern, R. J.; Morris, J.; Bloomer, S. H.

    1990-09-01

    Nd- and Sr-isotopic data are reported for lavas from 23 submarine and 3 subaerial volcanoes in the northern Mariana and southern Volcano arcs. Values of ɛNd range from +2.4 to +9.5 whereas 87Sr/86Sr ranges from 0.70319 to 0.70392; these vary systematically between and sometimes within arc segments. The Nd-and Sr-isotopic compositions fall in the field of ocean island basalt (OIB) and extend along the mantle array. Lavas from the Volcano arc, Mariana Central Island Province and the southern part of the Northern Seamount Province have ɛNd to +10 and 87Sr/86Sr=0.7032 to 0.7039. These are often slightly displaced toward higher 87Sr/86Sr at similar ɛNd. In contrast, those lavas from the northern part of the Mariana Northern Seamount Province as far north as Iwo Jima show OIB isotopic characteristics, with ɛNd and 87Sr/86Sr=0.7035 to 0.7039. Plots of 87Sr/86Sr and ɛNd versus Ba/La and (La/Yb)n support a model in which melts from the Mariana and Volcano arcs are derived by mixing of OIB-type mantle (or melts therefrom) and a metasomatized MORB-type mantle (or melts therefrom). An alternate interpretation is that anomalous trends on the plots of Nd- and Sr-isotopic composition versus incompatible-element ratios, found in some S-NSP lavas, suggest that the addition of a sedimentary component may be locally superimposed on the two-component mixing of mantle end-members.

  20. Southern Ocean air-sea heat flux, SST spatial anomalies, and implications for multi-decadal upper ocean heat content trends.

    NASA Astrophysics Data System (ADS)

    Tamsitt, V. M.; Talley, L. D.; Mazloff, M. R.

    2014-12-01

    The Southern Ocean displays a zonal dipole (wavenumber one) pattern in sea surface temperature (SST), with a cool zonal anomaly in the Atlantic and Indian sectors and a warm zonal anomaly in the Pacific sector, associated with the large northward excursion of the Malvinas and southeastward flow of the Antarctic Circumpolar Current (ACC). To the north of the cool Indian sector is the warm, narrow Agulhas Return Current (ARC). Air-sea heat flux is largely the inverse of this SST pattern, with ocean heat gain in the Atlantic/Indian, cooling in the southeastward-flowing ARC, and cooling in the Pacific, based on adjusted fluxes from the Southern Ocean State Estimate (SOSE), a ⅙° eddy permitting model constrained to all available in situ data. This heat flux pattern is dominated by turbulent heat loss from the ocean (latent and sensible), proportional to perturbations in the difference between SST and surface air temperature, which are maintained by ocean advection. Locally in the Indian sector, intense heat loss along the ARC is contrasted by ocean heat gain of 0.11 PW south of the ARC. The IPCC AR5 50 year depth-averaged 0-700 m temperature trend shows surprising similarities in its spatial pattern, with upper ocean warming in the ARC contrasted by cooling to the south. Using diagnosed heat budget terms from the most recent (June 2014) 6-year run of the SOSE we find that surface cooling in the ARC is balanced by heating from south-eastward advection by the current whereas heat gain in the ACC is balanced by cooling due to northward Ekman transport driven by strong westerly winds. These results suggest that spatial patterns in multi-decadal upper ocean temperature trends depend on regional variations in upper ocean dynamics.

  1. Impact of moisture flux convergence and soil moisture on precipitation: a case study for the southern United States with implications for the globe

    NASA Astrophysics Data System (ADS)

    Wei, Jiangfeng; Su, Hua; Yang, Zong-Liang

    2016-01-01

    Interactions between soil moisture, evapotranspiration (ET), atmospheric moisture fluxes and precipitation are complex. It is difficult to attribute the variations of one variable to another. In this study, we investigate the influence of atmospheric moisture fluxes and land surface soil moisture on local precipitation, with a focus on the southern United States (U.S.), a region with a strong humidity gradient and intense moisture fluxes. Experiments with the Weather Research and Forecasting model show that the variation of moisture flux convergence (MFC) is more important than that of soil moisture for precipitation variation over the southern U.S. Further analyses decompose the precipitation change into several contributing factors and show that MFC affects precipitation both directly through changing moisture inflow (wet areas) and indirectly by changing the precipitation efficiency (transitional zones). Soil moisture affects precipitation mainly by changing the precipitation efficiency, and secondly through direct surface ET contribution. The greatest soil moisture effects are over transitional zones. MFC is more important for the probability of heavier rainfall; soil moisture has much weaker impact on rainfall probability and its roles are similar for the probability of intermediate-to-heavy rainfall (>10 mm day-1). Although MFC is more important than soil moisture for precipitation over most regions, the impact of soil moisture could be large over certain transitional regions. At the submonthly time scale, the African Sahel appears to be the only major region where soil moisture has a greater impact than MFC on precipitation. This study provides guidance to understanding and further investigation of the roles of local land surface processes and large-scale circulations on precipitation.

  2. Geology of the Eel River basin and adjacent region: Implications for late Cenozoic tectonics of the southern Cascadia subduction zone and Mendocino triple junction

    SciTech Connect

    Clarke, S.H. Jr. )

    1992-02-01

    Two upper Cenozoic depositional sequences of principally marine strata about 4,000 m thick overlie accreted basement terranes of the Central and Coastal belts of the Franciscan Complex in the onshore-offshore Eel River basin of northwestern California. The older depositional sequence is early to middle Miocene in age and represents slope basin and slope-blanket deposition, whereas the younger sequence, later Miocene to middle Pleistocene in age, consists largely of forearc basin deposits. Youthful tectonic activity related to Gorda-North American plate convergence indicates an active Cascadia subduction zone and strong partial coupling between these plates. Structures of the northeastern margin of the Eel River basin are principally north-northwest-trending, east-northeast-dipping thrust and reverse faults that form imbricate thrust fans. The Coastal belt fault, the early Tertiary accretionary suture between the Franciscan Central and Coastal belts, can be traced from Arcata Bay northward offshore to the southern Oregon border. It is tentatively extended farther northward based on aeromagnetic data to an offshore position west of Cape Blanco. Thereafter, it may coincide with the offshore Fulmar fault. The Cascadia subduction zone (CSZ) does not join the Mendocino transform fault at the commonly depicted offshore location of the Mendocino triple junction (MTJ). Instead, the CSZ extends southeastward around the southern Eel River basin and shoreward along Mendocino Canyon to join the Petrolia shear zone. Similarly, the Mendocino fault may extend shoreward via Mattole Canyon and join the Cooskie shear zone. These two shear zones intersect onshore north of the King Range, and the area of their intersection is the probable location of the MTJ.

  3. The upper lithostratigraphic unit of ANDRILL AND-2A core (Southern McMurdo Sound, Antarctica): local Pleistocene volcanic sources, paleoenvironmental implications and subsidence in the southern Victoria Land Basin

    NASA Astrophysics Data System (ADS)

    Del Carlo, P.; Panter, K. S.; Bassett, K. N.; Bracciali, L.; di Vincenzo, G.; Rocchi, S.

    2009-12-01

    We report results from the study of the uppermost 37 meters of the Southern McMurdo Sound (SMS) AND-2A drillcore, corresponding to the lithostratigraphic unit 1 (LSU 1), the most volcanogenic unit within the core. Nearly all of LSU 1 consists of volcanic breccia and sandstone that is a mixture of near primary volcanic material dominated by lava and vitric clasts with minor exotic material derived from distal basement sources. Lava clasts and glass are mafic and range from strongly alkaline (basanite, tephrite) to moderately alkaline (alkali basalt, hawaiite) compositions that are similar to nearby land deposits. 40Ar-39Ar laser step-heating analyses on groundmass separated from lava clasts yield Pleistocene ages (692±38 and 793±63, ±2σ internal errors). Volcanoes of the Dailey Island group, located ~13 km SW of the drillsite, are a possible source for the volcanic materials based on their close proximity, similar composition and age. A basanite lava flow on Juergens Island yields a comparable Pleistocene age of 775±22 ka. Yet there is evidence to suggest that the volcanic source is much closer to the drillsite and that the sediments were deposited in much shallower water relative to the present-day water depth of 384 mbsl. Evidence for local volcanic activity is based in part on the common occurrence of delicate vitriclasts (e.g. glass shards and Pele’s hair) and a minimally reworked ~2 meter thick monomict breccia that is interpreted to have formed by autobrecciating lava. In addition, conical-shaped seamounts and high frequency magnetic anomalies encompass the drillsite and extend south including the volcanoes of the Dailey Islands. Sedimentary features and structures indicate shallow water sedimentation for the whole of LSU 1. Rippled asymmetric cross-laminated sands and hummocky cross-stratification occur intermittently throughout LSU 1 and indicate water depths shallower than 100 meters. The occurrence of ooliths and layers containing siderite and Fe

  4. Representation of drought frequency in Southern South America performed by 14 CMIP5 models. Drought risk implications and perspectives towards future projections

    NASA Astrophysics Data System (ADS)

    Rivera, J. A.; Penalba, O. C.

    2012-12-01

    Drought frequency estimation is a key variable for drought risk assessment. The aim of this research is to evaluate how well the global climate models (GCMs) represent the drought frequencies in Southern South America (south of 20°S). For that purpose, we used the Standardized Precipitation Index (SPI), which quantifies the number of standard deviations that the accumulated rainfall in a given time scale deviates from the average value of a location in a particular period. The SPI is one of the drought indices most widely used worldwide, and one of the best suited for the study area. In order to build this index, monthly rainfall data were obtained from the CLARIS LPB Data Base for 120 of its stations, which were subjected to quality control procedures and have less than 10% of missing values. The SPI was computed for the period 1979-2008 on a time scale of 12 months, which represents long-term droughts. This procedure was also applied to the simulated precipitation from 14 CMIP5 GCMs over the study area. Two types of comparisons were performed, the first one for drought frequencies without taking into account the different drought classes and the second one for the frequencies of moderate, severe and extreme drought events. This second comparison is important given that drought risk was evaluated through a weighted index based in drought frequencies, which was constructed as a sum of drought classes -moderate, severe and extreme- with a weighting scheme. Most of the regions with moderate to high observed drought frequencies are located in the western and southern portions of La Plata Basin and over Patagonia region, while lower observed drought frequencies were obtained for Northern Argentina, Southern Brazil and Paraguay. This spatial pattern is barely reproduced by the modeled frequencies, and in some cases major differences exist. In order to analyze these differences, we performed a regional assessment of the SPI time series, which showed that the time series

  5. Comprehensive Waveform Cross-correlation of Southern California Seismograms: Part 1. Refined Hypocenters Obtained Using the Double-difference Method and Tectonic Implications

    NASA Astrophysics Data System (ADS)

    Hauksson, E.; Chi, W.; Shearer, P.

    2003-12-01

    We present preliminary results applying waveform cross-correlation to southern California seismograms for over 380,000 events between 1984 and 2002. Waveforms recorded by the SCSN are first extracted from the SCEDC data center in 50 s windows that include both P and S waves. The resulting online waveform archive uses about 0.5 TB on a RAID system. The traces are then re-sampled to a uniform 100 Hz sample rate and band-pass filtered to between 1 and 10 Hz. Next, we apply time domain waveform cross-correlation for P and S waves between each event and 100 neighboring events (identified from the catalog based on a 3-D velocity model of Hauksson (2000). We identify and save differential times from the peaks in the cross-correlation functions and use a spline interpolation method to achieve a nominal timing precision of 0.001 s. These differential times, together with existing P and S phase picks, are input to the double-difference program of Waldhauser and Ellsworth (2000). We define a grid across southern California and locate hypocenters near each grid node. Because some events may be located many times as hypocenters are calculated near successive grid-points, we assign a weight to each hypocenter and calculate a weighted average hypo-center for each earthquake. The new HypoDD hypocenters show improved clustering both horizontally and vertically, creating a more focused picture of the previously identified, spatially complex distributions of seismicity. In many cases, the late Quaternary faults, such as the Elsinore and Hollywood-Santa Monica faults appear to bracket the seismicity distributions; in other cases, the faults trace the median within a symmetric distribution of hypocenters. The depth distribution of the seismicity shows sudden changes across some of the major strike-slip faults, while regions of dip-slip faulting are often bound by dipping surfaces that are clearly defined by the deepest hypocenters. The seismicity around the southern San Andreas fault

  6. A lithofacies terrain model for the Blantyre Region: Implications for the interpretation of palaeosavanna depositional systems and for environmental geology and economic geology in southern Malawi

    NASA Astrophysics Data System (ADS)

    Dill, H. G.; Ludwig, R.-R.; Kathewera, A.; Mwenelupembe, J.

    2005-06-01

    The Blantyre City Area is part of the African savanna in southern Malawi. Sedimentological, geomorphological, chemical and mineralogical studies were conducted to create a lithofacies terrain model. The project involves mapping, cross-sectioning, grain size, heavy mineral analysis, XRD and the study of sedimentary textures under the petrographic microscope. These classical techniques were combined with GIS-based field and office works. The combined efforts led to 2-D maps and 3-D block diagrams that illustrate the geomorphological and sedimentological evolution of the landscape in southern Malawi during the late Mesozoic and Cenozoic. The results obtained through integrated geomorphological-sedimentological studies form the basis for land management (planning of residential areas, waste disposal sites, assessment of bearing capacity of rocks), geohazard prediction (delineation of high risk zones in terms of mass flow and inundation) and the evaluation of high-place (ceramic raw materials) and high-unit value (placers of precious metals and gemstones) mineral commodities in the study area. The study addresses regional and general aspects alike. In regional terms, the study aimed at unraveling the evolution of landforms at the southern end of the East African Rift System during the most recent parts of the geological past. Four stages of peneplanation were established in the working area. Planation was active from the Cretaceous to the Quaternary (stage I: early to mid-Cretaceous, stage II: early Tertiary, stage III: early to mid-Tertiary, stage IV: mid- to late Tertiary). During the most recent parts of the Quaternary, strong fluvial incision was triggered by the base-level lowering of the Shire River. Geomorphological alteration of the landscape goes along with a phyllosilicate-sesquioxide transformation from minerals indicative of more acidic meteoric fluids (e.g., gibbsite, kaolinite) to those typical of more alkaline conditions (e.g. smectite, vermiculite

  7. Influence of climate and land use in carbon biogeochemistry in lower reaches of rivers in central southern Chile: Implications for the carbonate system in river-influenced rocky shore environments

    NASA Astrophysics Data System (ADS)

    Pérez, Claudia A.; DeGrandpre, Michael D.; Lagos, Nelson A.; Saldías, Gonzalo S.; Cascales, Emma-Karin; Vargas, Cristian A.

    2015-04-01

    Freshwater discharge affects the biogeochemistry of river-influenced nearshore environments by contributing with carbon and nutrients. An increase in human activities in river basins may alter the natural riverine nutrients and carbon export to coastal ecosystems. Along a wide latitudinal range (32°55'S-40°10'S), this study explores the role of climate and land use in determining the nutrient and carbon concentrations in the river mouth and fluxes to adjacent coastal areas. Between winter 2011 and fall 2012, we collected monthly samples in five river mouths in central southern Chile and at rocky shore sites affected by river plumes. Basins were characterized by different land uses and meteorological conditions along this latitudinal range. Water samples were collected for pH measurements, nutrients, dissolved organic and inorganic carbon, particulate organic carbon, and isotopic signatures (δ13C). Our results show a north-south gradient in concentrations of nutrients and carbon. The highest concentrations were observed in the Maipo basin, which presents the highest percentage of urban-industrial activities. Nutrients and carbon contributions, in most cases, were lowest in the southern Valdivia basin, which has the least human intervention and a greater percentage of vegetation. The Biobío River had the highest nutrient and carbon fluxes, in most cases, due to its high river discharge. Our results show the influence of river plume effects on carbon and nitrogen concentrations in river-influenced rocky shore sites. Moreover, our study suggests that land use might influence some parameters of carbonate system in rivers and river-influenced rocky shore environments. River-influenced rocky shore environments may exhibit suppression in aragonite saturation state with implications for calcifiers inhabiting these marine environments.

  8. 1.4 kyrs of flash flood events in the Southern European Alps: implications for extreme precipitation patterns and forcing over the north-western Mediterranean area

    NASA Astrophysics Data System (ADS)

    Wilhelm, B.; Arnaud, F.; Sabatier, P.; Crouzet, C.; Brisset, E.; Guiter, F.; Reyss, J. L.; Chaumillon, E.; Tachikawa, K.; Bard, E.; Delannoy, J. J.

    2012-04-01

    Extreme precipitation events trigger flash floods causing large human and economic losses. Their frequency and/or intensity are expected to increase in the context of global warming, especially in the Mediterranean region. However, the relationship between such events and past climate change remains difficult to assess. Indeed, the stochastic nature of extreme event occurrence precludes the identification of trends. This is reinforced by a lack in long-term instrumental data. It is hence essential to reconstruct long-term geological records of intense events to extend documented records beyond the observational data. This will enable a better understanding of local to regional flood hazard patterns in the context of global warming and hence improve predictive models. In the framework of Pygmalion research program, a multiproxy investigation of the Lake Allos (2230 m a.s.l., Southern French Alps) sediment sequence revealed the presence of 160 flood-triggered interbedded layers within a 1400-long sequence. Owing to sedimentary and geochemical characteristics and the frequent occurrence, such deposits were interpreted as the result of high-energy sediment inputs during intense torrential floods (i.e. flash-floods), related to extreme precipitation events. Furthermore the significant relationship between the thickness and the basal grain size of the graded beds allowed using the thickness as a proxy of the flood intensity. Trough the comparison with local historic flood reconstructions over the last 400 years, we argue that these flash floods were mostly triggered by autumnal meso-scale intense precipitation events. Since the Medieval Climate Anomaly (MCA), the absence of major change in erosion processes and local vegetation dynamics linked to anthropogenic impact led us to interpret the Allos flood record as the proxy for the occurrence of such extreme precipitation events over the last millennium. The frequency of Allos flash-flood events appeared consistent with

  9. Early Cretaceous low-Mg# adakitic rocks in the southern margin of the central North China Craton: Partial melting of thickened lower continental crust and tectonic implications

    NASA Astrophysics Data System (ADS)

    Yang, D.

    2015-12-01

    This paper reports new whole-rock geochemical, Sr-Nd-Pb isotopic, and zircon U-Pb and Hf isotopic data for Early Cretaceous intrusive rocks in the Sanmenxia-Houma area of central China, and uses these data to constrain the petrogenesis of low-Mg adakitic rocks (LMAR) and the spatial extent of the influence of the deeply subducted Yangtze slab during the Triassic evolution of this region. New zircon LA-ICP-MS U-Pb data indicate that the early- and late-stage southern Quli, Qiligou, and Gaomiao porphyritic quartz diorites, the Canfang granodiorite, and the northern Wangmao porphyritic quartz monzodiorite were emplaced during the Early Cretaceous (~130 Ma) and the late Early Cretaceous (116 Ma). These rocks are characterized by high Na2O/K2O, Sr/Y, and (La/Yb)n ratios as well as high Sr concentrations, low Mg# values, and low heavy rare earth element and Y concentrations, all of which indicate an LMAR affinity. The samples have relatively high initial 87Sr/86Sr ratios (0.7054-0.7095), and low eNd(t) (-11.90 to -22.20) and eHf(t) (-16.7 to -32.7) values, indicative of a lower continental crust origin. The presence of Neoproterozoic (754-542 Ma) and inherited Late Triassic (220 Ma) metamorphic zircons within the late Early Cretaceous LMAR and the relatively high 206Pb/204Pb ratios of these rocks suggest that they formed from primary magmas derived from partial melting of Yangtze Craton (YC) basement material that had undergone ultrahigh-pressure metamorphism. In contrast, the presence of Paleoproterozoic and Archean inherited zircons within early Early Cretaceous LMAR in this area and the relatively low 206Pb/204Pb ratios of these rocks are indicative of derivation from primary magmas generated by partial melting of the thickened lower continental crust of the North China Craton (NCC). These rocks may have formed in an extensional environment associated with the upwelling of asthenospheric mantle material. The presence of YC basement material within the NCC in the

  10. Elemental and Sr Nd isotopic systematics of the early Mesozoic volcanic sequence in southern Jiangxi Province, South China: petrogenesis and tectonic implications

    NASA Astrophysics Data System (ADS)

    Wang, Yuejun; Fan, Weiming; Peng, Touping; Guo, Feng

    2005-02-01

    Elemental and Sr Nd isotopic results are presented for the early Mesozoic volcanic sequence (~172 Ma) in southern Jiangxi Province, South China. The sequence is voluminously composed of ~45% subalkaline basaltic rocks (group 1), <5% high-mg andesite dacites (group 2) and ~50% rhyolites (group 3). The group 1 rocks are characterized by (La/Yb)cn = 3.8 7.2, Eu/Eu* = 0.65 1.15, Nb/La = 0.64 0.99, 87Sr/86Sr(t) = 0.70602~0.70822 and ɛNd(t) = -1.63 to +0.11, similar to those of an EMII-like source. The group 2 rocks have mg=0.42~0.60, SiO2=60.24~66.71%, MgO=2.65~ 5.54%, Ni=24~102 ppm and Cr=84~266 ppm, classified as high-mg andesitic rocks. These rocks are more enriched in LILEs and LREE with more significant negative Eu anomaly (0.63~0.79), are more depleted in HFSEs with Nb/La ratios of 0.40 0.56 and have lower ɛNd(t) (-9.44 to -7.78) and higher 87Sr/86Sr(t) (0.70985~0.71016), in comparison with the group 1 rocks. They most likely originated from metasomatised veins in the lithospheric mantle. The origination of the group 1 and group 2 magma suggests the development of a peridotite-plus-vein lithospheric mantle during early Mesozoic era beneath the interior of the Cathaysian block. The group 3 rhyolites are characterized by high SiO2 (72.75~77.97%), Zr (99~290 ppm), Hf (3.9~9.7 ppm) and Ga/Al (2.76~3.87) and significant Nb Ta, Ba Sr and P Ti depletions. These rhyolites exhibit Sr Nd isotopic compositions (87Sr/86Sr(t) = 0.70962~0.71104, ɛNd(t) = -4.63 to -5.80) similar to the contemporaneous Zhaibei and Pitou A-type granites in the area. Such characteristics suggest that they might be derived from the underplating basaltic magma contaminated by crustal materials. Therefore, an early Mesozoic rifting model in response to intracontinental lithospheric extension is proposed to account for the early Mesozoic volcanism in southern Jiangxi Province, South China.

  11. Northern versus southern gateways control on ocean overturning circulation at the Eocene-Oligocene transition and possible implications to global cooling

    NASA Astrophysics Data System (ADS)

    Abelson, M.; Erez, J.

    2013-12-01

    There is a growing body of evidence indicating reorganization in the ocean overturning circulation during the transition from the Eocene to the Oligocene, in particular, the initiation of the northern-sourced overturning circulation that comprises the northern component water (NCW) and northward flowing intermediate water. This evidence includes Nd isotopes from the Southern Hemisphere, δ13C from intermediate water in the subtropical North Atlantic, and increasing difference in the benthic δ18O between the Northern and Southern Hemispheres. We compare all these sets of proxies and show that the increasing trends have been conjugated throughout most of the Oligocene indicating enhancement of the northern-sourced overturning circulation that began around the Eocene-Oligocene transition (EOT). This reorganization was attributed mainly to the development of the wind-driven Antarctic circumpolar current (ACC). Based on variety of geological inferences, we suggest that the shift to interhemispheric bipolar overturning circulation was initiated by buoyancy fluxes formed by the development of anti-estuarine circulation between the Nordic Seas and the North Atlantic around the EOT, which significantly intensified the NCW. The Nordic anti-estuarine circulation began at a critical threshold during rapid tectonic subsidence of the Greenland-Scotland Ridge (GSR) triggered by the suppression of the Iceland mantle plume. We show that the development of northern-sourced circulation cell during the Oligocene correlates compellingly with the histories of the GSR subsidence and the activity of the Iceland mantle plume, and to a lesser degree with the ACC history. Accordingly, this circulation was enhanced as long as the GSR subsided rapidly. The onset of the northern-sourced overturning circulation, which is the biologically productive circulation domain, has probably triggered the marked increase in the ocean productivity during the EOT. The relationship between the EOT climatic

  12. Habitat overlap between southern bluefin tuna and yellowfin tuna in the east coast longline fishery - implications for present and future spatial management

    NASA Astrophysics Data System (ADS)

    Hartog, Jason R.; Hobday, Alistair J.; Matear, Richard; Feng, Ming

    2011-03-01

    Southern bluefin tuna (SBT) are presently a quota-managed species in the multi-species eastern Australian tuna and billfish longline fishery (ETBF). Capture of SBT is regulated by quota, as is access to regions likely to contain SBT. A habitat prediction model combining data from an ocean model and pop-up satellite archival tags is used to define habitat zones based on the probability of SBT occurrence. These habitat zones are used by fishery managers to restrict access by ETBF fishers to SBT habitat during a May-November management season. The zones display a distinct seasonal cycle driven by the seasonal southward expansion and northward contraction of the East Australia Current (EAC) and as a result access by fishers to particular ocean regions changes seasonally. This species also overlaps with the commercially valuable yellowfin tuna (YFT), thus, we modified the SBT model to generate YFT habitat predictions in order to investigate habitat overlap between SBT and YFT. There is seasonal variation in the overlap of the core habitat between these two species, with overlap early (May-Jul) in the management season and habitat separation occurring towards the end (Aug-Nov). The EAC is one of the fastest warming ocean regions in the southern hemisphere. To consider the future change in distribution of these two species compared to the present and to explore the potential impact on fishers and managers of the future, we use future ocean predictions from the CSIRO Bluelink ocean model for the year 2064 to generate habitat predictions. As the ocean warms on the east coast of Australia and the EAC extends southward, our model predicts the suitable habitat for SBT and YFT will move further south. There was an increase in the overlap of SBT and YFT habitat throughout the management season, due to regional variation of each species' habitat. These results illustrate that a management tradeoff exists between restricting fisher access to SBT habitat and allowing access to YFT

  13. Provenance Ages of Protoliths From the Chiapas Massif Complex and Adjacent Strata of the Southern Maya Block - Implications on the Paleozoic Reconstruction of Middle America.

    NASA Astrophysics Data System (ADS)

    Weber, B.; Schaaf, P.; Valencia, V. A.; Lopez-Martinez, M.; Ortega-Gutierrez, F.

    2007-05-01

    The basement of the Maya block is exposed in the Maya Mountains of Belize, the Chuacús Complex of Guatemala, and in the Chiapas Massif Complex (CMC) of SE Mexico. In the CMC medium- to high-grade metasedimentary rocks occur as isolated domains in mostly metaigneous crystalline rocks. The most important tectonothermal event in the entire CMC is of late Permian age, culminating in partial anatexis and the intrusion of the Chiapas batholith. In this work we present U-Pb data obtained by LA-MC-ICPMS from detrital zircon cores of metasediments from the CMC and from detrital zircons of Paleozoic strata exposed in SE Chiapas. The Pennsylvanian-Permian Santa Rosa Formation (SRF) contains mostly Pan-African (500-650 Ma) zircons, minor populations of Silurian-Early Devonian (400-420 Ma) and Grenville (1.0-1.25 Ga) zircons, and few Paleoproterozoic and Archean grains. The maximum sedimentation age is documented by ~320 Ma old zircons. Metagreywacke and metasandstones of the central CMC have inherited detrital zircon cores with age distributions indistinguishable from those of the SRF. High-grade metapelites and para-amphibolites from the CMC, instead, have inherited zircon cores with one single population of 1.0 Ga or with populations at 1.0, 1.2, and 1.5 Ga. In the southern part of the CMC leucocratic granites intrude sedimentary rocks whose detrital zircons yielded mostly 1.53 Ga ages with some grains in the range of 1.6-1.7 Ga, but no younger zircons. White mica grown in contact with the leucogranite has a 40Ar- 39Ar age of 406 ± 4 Ma, defining a minimum age for both deposition of the sediments and intrusion of the leucogranite. Our data indicate that the CMC has a composite pre-metamorphic basement, containing sedimentary protoliths from the Pennsylvanian-Permian SRF and from early Paleozoic strata intruded by Silurian-Early Devonian granites. This favors a similar pre-Permian geologic history for the CMC as for the Maya Mountains of Belize. The early Paleozoic

  14. Early evolution of the southern margin of the Neuquén Basin, Argentina: Tectono-stratigraphic implications for rift evolution and exploration of hydrocarbon plays

    NASA Astrophysics Data System (ADS)

    D'Elia, Leandro; Bilmes, Andrés; Franzese, Juan R.; Veiga, Gonzalo D.; Hernández, Mariano; Muravchik, Martín

    2015-12-01

    Long-lived rift basins are characterized by a complex structural and tectonic evolution. They present significant lateral and vertical stratigraphic variations that determine diverse basin-patterns at different timing, scale and location. These issues cause difficulties to establish facies models, correlations and stratal stacking patterns of the fault-related stratigraphy, specially when exploration of hydrocarbon plays proceeds on the subsurface of a basin. The present case study corresponds to the rift-successions of the Neuquén Basin. This basin formed in response to continental extension that took place at the western margin of Gondwana during the Late Triassic-Early Jurassic. A tectono-stratigraphic analysis of the initial successions of the southern part of the Neuquén Basin was carried out. Three syn-rift sequences were determined. These syn-rift sequences were located in different extensional depocentres during the rifting phases. The specific periods of rifting show distinctly different structural and stratigraphic styles: from non-volcanic to volcanic successions and/or from continental to marine sedimentation. The results were compared with surface and subsurface interpretations performed for other depocentres of the basin, devising an integrated rifting scheme for the whole basin. The more accepted tectono-stratigraphic scheme that assumes the deposits of the first marine transgression (Cuyo Cycle) as indicative of the onset of a post-rift phase is reconsidered. In the southern part of the basin, the marine deposits (lower Cuyo Cycle) were integrated into the syn-rift phase, implying the existence of different tectonic signatures for Cuyo Cycle along the basin. The rift climax becomes younger from north to south along the basin. The post-rift initiation followed the diachronic ending of the main syn-rift phase throughout the Neuquén Basin. Thus, initiation of the post-rift stage started in the north and proceeded towards the south, constituting a

  15. Tectonic geomorphology and paleoseismology of strike-slip faults in Jamaica: Implications for distribution of strain and seismic hazard along the southern edge of the Gonave microplate

    NASA Astrophysics Data System (ADS)

    Koehler, R. D.; Mann, P.; Brown, L. A.

    2009-12-01

    The east-west, left lateral strike-slip fault system forming the southern edge of the Gonave microplate crosses the110-km-long and 70-km-wide island of Jamaica. GPS measurements in the northeastern Caribbean are supportive of the microplate interpretation and indicate that ~ half of the Caribbean-North America left-lateral plate motion (8-14 mm/yr) is carried by the Plantain Garden (PGFZ) and associated faults in Jamaica. We performed Neotectonic mapping of the Plantain Garden fault along the southern rangefront of the Blue Mountains and conducted a paleoseismic study of the fault at Morant River. Between Holland Bay and Morant River, the fault is characterized by a steep, faceted, linear mountain front, prominent linear valleys and depressions, shutter ridges, and springs. At the eastern end of the island, the PGFZ is characterized by a left-stepping fault geometry that includes a major, active hot spring. The river cut exposure at Morant River exposes a 1.5-m-wide, sub-vertical fault zone juxtaposing sheared alluvium and faulted Cretaceous basement rocks. This section is overlain by an, unfaulted 3-m-thick fluvial terrace inset into a late Pleistocene terrace that is culturally modified. Upward fault terminations indicate the occurrence of three paleoearthquakes that occurred prior to deposition of the flat lying inset terrace around 341-628 cal yr BP. At this time, our radiocarbon results suggest that we can rule out the PGFZ as the source of the 1907 Kingston earthquake 102 years ago, as well as, the 1692 event that destroyed Port Royal 317 years ago and produced a major landslide at Yallahs. Pending OSL ages will constrain the age of the penultimate and most recent ruptures. Gently to steeply dipping rocks as young as Pliocene exposed in roadcuts within the low coastal hills south of and parallel to the Plantain Garden fault may indicate active folding and blind thrust faulting. These structures are poorly characterized and may accommodate an unknown amount of

  16. Surface exposure chronology of the Waimakariri glacial sequence in the Southern Alps of New Zealand: Implications for MIS-2 ice extent and LGM glacial mass balance

    NASA Astrophysics Data System (ADS)

    Rother, Henrik; Shulmeister, James; Fink, David; Alexander, David; Bell, David

    2015-11-01

    During the late Quaternary, the Southern Alps of New Zealand experienced multiple episodes of glaciation with large piedmont glaciers reaching the coastal plains in the west and expanding into the eastern alpine forelands. Here, we present a new 10Be exposure age chronology for a moraine sequence in the Waimakariri Valley (N-Canterbury), which has long been used as a reference record for correlating glacial events across New Zealand and the wider Southern Hemisphere. Our data indicate that the Waimakariri glacier reached its maximum last glaciation extent prior to ∼26 ka well before the global last glaciation maximum (LGM). This was followed by a gradual reduction in ice volume and the abandonment of the innermost LGM moraines at about 17.5 ka. Significantly, we find that during its maximum extent, the Waimakariri glacier overflowed the Avoca Plateau, previously believed to represent a mid-Pleistocene glacial surface (i.e. MIS 8). At the same time, the glacier extended to a position downstream of the Waimakariri Gorge, some 15 km beyond the previously mapped LGM ice limit. We use a simple steady-state mass balance model to test the sensitivity of past glacial accumulation to various climatic parameters, and to evaluate possible climate scenarios capable of generating the ice volume required to reach the full local-LGM extent. Model outcomes indicate that under New Zealand's oceanic setting, a cooling of 5 °C, assuming modern precipitation levels, or a cooling of 6.5 °C, assuming a one third reduction in precipitation, would suffice to drive the Waimakariri glacier to the eastern alpine forelands (Canterbury Plains). Our findings demonstrate that the scale of LGM glaciation in the Waimakariri Valley and adjacent major catchments, both in terms of ice volume and downvalley ice extent, has been significantly underestimated. Our observation that high-lying glacial surfaces, so far believed to represent much older glacial episodes, were glaciated during the LGM

  17. Paleoseismologic evidence for late Holocene earthquakes on the Southern Panamint Valley fault zone: Implications for earthquake clustering in the Eastern California Shear Zone north of the Garlock fault

    NASA Astrophysics Data System (ADS)

    McAuliffe, L. J.; Dolan, J. F.; Kirby, E.; Haravitch, B.; Alm, S.

    2010-12-01

    New paleoseismological data from two trenches excavated across the southern end of the Panamint Valley fault (PVF), the most active of the three major faults in the eastern California shear zone (ECSZ) north of the Garlock fault, reveal the occurrence of at least two, and probably three, surface ruptures during the late Holocene. These trenches were designed to test the hypothesis that the earthquake clusters and intervening seismic lulls observed in the Mojave section of the ECSZ (Rockwell et al. 2000, Ganev et al. 2010) at 8-9.5 ka, 5-6 ka and during the past ~1-1.5 ka, also involved the fault systems of the ECSZ north of the Garlock fault. Well stratified playa sands, silts and clays exposed in the trench allowed precise identification of two event horizons; a likely third event horizon occurred during a period of soil development across the playa. Calibrated radiocarbon dates from 25 charcoal samples constrain the dates of the most recent event (MRE) to ~1450-1500 AD and the ante-penultimate event at 3.2-3.6 ka. The penultimate event occurred during a period of soil development spanning ~350-1400 AD. The presence of large blocks of soil in what appears to be scarp-derived colluvium in a large fissure opened during this event require that it occurred late during soil development, probably only a few hundred years before the MRE. The timing of the three events indicate that the southern PVF has ruptured at least once, and probably twice during the ongoing seismic cluster in the Mojave region. The PVF earthquakes also are similar in age to the 1872 Owens Valley earthquakes and the geomorphically youthful, but undated MRE in central Death Valley. Although we were unable to excavate deeply enough at this site to expose mid-to lower - Holocene playa strata, the timing of the ante-penultimate earthquake at our site shows that the PVF has ruptured at least once during the well-defined 2-5 ka seismic lull in the Mojave section of the ECSZ. Interestingly the 3.2-3.6 ka

  18. Regional variations in upper mantle compressional velocities beneath southern California 1. Post-shock temperatures: Their experimental determination, calculation, and implications, 2.. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Raikes, S. A.

    1978-01-01

    The compressional velocity within the upper mantle beneath Southern California is investigated through observations of the dependence of teleseismic P-delays at all stations of the array on the distance and azimuth to the event. The variation of residuals with azimuth was found to be as large as 1.3 sec at a single station; the delays were stable as a function of time, and no evidence was found for temporal velocity variations related to seismic activity in the area. These delays were used in the construction of models for the upper mantle P-velocity structure to depths of 150 km, both by ray tracing and inversion techniques. The models exhibit considerable lateral heterogeneity including a region of low velocity beneath the Imperial Valley, and regions of increased velocity beneath the Sierra Nevada and much of the Transverse Ranges. The development is described of a technique for the experimental determination of post-shock temperatures, and its application to several metals and silicates shocked to pressures in the range 5 to 30 GPa. The technique utilizes an infra-red radiation detector to determine the brightness temperature of the free surface of the sample after the shock wave has passed through it.

  19. Illite-smectite patterns in sheared Pleistocene mudstones of the Southern Apennines and their implications regarding the process of illitization: A multiscale analysis

    NASA Astrophysics Data System (ADS)

    Casciello, Emilio; Cosgrove, John W.; Cesarano, Massimo; Romero, Enrique; Queralt, Ignasi; Vergés, Jaume

    2011-11-01

    The transformation of water-rich smectite clay minerals into relatively anhydrous illite is a common reaction in sedimentary basins. It is commonly thought to be driven by temperature increase with increasing burial depth. This mineral transformation is also observed in the gouge of large faults, and because it releases bound water from smectite, it is thought to be a key control in hydrologic and mechanical processes at subduction complexes. In this work, the distribution of smectite and illite within a large fault zone of the Southern Apennines of Italy is analysed at scales varying from outcrop to sub millimetre. X-ray diffraction analyses indicate a direct link between the darkening in colour of the sheared mudstone and the illitization of smectite. The heterogeneous distribution of illite and smectite within this shear zone was studied by integrating outcrop-scale observations with a peeling technique that allows microscope and SEM observations to be made over areas in excess of 60 cm2. The observed patterns of smectite illitization suggest that temperature is not the primary cause of the mineral transformation inside the fault. The distribution of illite along planes of the P foliation and in the infill of shears indicates that shear stress facilitates the mineral transformation.

  20. The AyiaTriadha Cave, Southern Euboea Finds and Implications of the Earliest Human Habitation in the Area (A Preliminary Report).

    NASA Astrophysics Data System (ADS)

    Mavridis, F.; Tankosić, Ž.

    The Ayia Triadha cave excavation project aims to explore early maritime connections in the Aegean during the Late Neolithic I and II and the Early Bronze Age. The cave lies in a strategic position close to the crossroads that connect insular regions and the mainland. We also aim to explore the manifestations of the so-called Saliagos culture of the Cyclades and the Aegean. This culture is connected to the White-on-Dark pottery horizon (late sixth to early fifth millennium B.C.) found in the cave. The Final Neolithic/LNIIa material is also present in the cave in large quantities. It is closely connected to the Attica-Kephala horizon (late fifth/fourth millennium B.C.) known from the Cyclades and the southern part of mainland Greece. Of great importance is the identification of an Early Bronze Age context, located inside a small chamber, off the main entrance corridor. In this paper we present our preliminary results from the 2007 field season and some aspects of the 2008 campaign together with research strategies we plan to apply in the future.