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Sample records for basins north central

  1. Structural controls on a geothermal system in the Tarutung Basin, north central Sumatra

    Science.gov (United States)

    Nukman, Mochamad; Moeck, Inga

    2013-09-01

    The Sumatra Fault System provides a unique geologic setting to evaluate the influence of structural controls on geothermal activity. Whereas most of the geothermal systems in Indonesia are controlled by volcanic activity, geothermal systems at the Sumatra Fault System might be controlled by faults and fractures. Exploration strategies for these geothermal systems need to be verified because the typical pattern of heat source and alteration clays are missing so that conventional exploration with magnetotelluric surveys might not provide sufficient data to delineate favorable settings for drilling. We present field geological, structural and geomorphological evidence combined with mapping of geothermal manifestations to allow constraints between fault dynamics and geothermal activity in the Tarutung Basin in north central Sumatra. Our results indicate that the fault pattern in the Tarutung Basin is generated by a compressional stress direction acting at a high angle to the right-lateral Sumatra Fault System. NW-SE striking normal faults possibly related to negative flower structures and NNW-SSE to NNE-SSW oriented dilative Riedel shears are preferential fluid pathways whereas ENE-WSW striking faults act as barriers in this system. The dominant of geothermal manifestations at the eastern part of the basin indicates local extension due to clockwise block rotation in the Sumatra Fault System. Our results support the effort to integrate detailed field geological surveys to refined exploration strategies even in tropical areas where outcrops are limited.

  2. Gravity modeling constraints on the Gatun-Chagres Basin and tectonic evolution of north-central Panama

    Science.gov (United States)

    Mynhier, Kelci

    The Oligocene-Miocene collision between Panama and South America significantly influenced ocean currents, global climate, and species diversification. Intraplate deformation of the Panama Block also played an important role in the evolution of this tectonic system, but is not well understood. A high-resolution gravity survey, coupled with geologic observations, was conducted in north-central Panama to better constrain the processes responsible for the Isthmus' modern configuration. Approximately 110 gravity stations were collected from Colon to Nombre de Dios, Panama and merged with existing data. Subsequently, four 2.5-D gravity models were produced to constrain the geometry of the Gatun-Chagres Basin using different sedimentary densities (1.8, 2.0, and 2.2 g/cm 3) to produce a realistic range of basin thicknesses. Overall, models with an average basin density of 2.0 g/cm3 are most consistent with offshore seismic profiles and field evidence, suggesting basin thickness is ~3.0--3.5 km. Previous seismic reflection data and geochemical analyses of Miocene arc volcanic rocks delineate a zone of extension in the Panama Canal Region, and gravity analysis from this study supports this hypothesis. Field evidence of multiple NW-facing normal faults suggests that they separate the basin from uplifted arc basement rocks east of the Canal, resulting in a 60 mGal gravity gradient. Beneath the basin, gravity models indicate ~5--10 km of crustal thinning. 3-D reconstruction of the 2.5-D models show a northward thickening basin and two depocenters that correspond to the Rio Indio and Toro facies of the Chagres Formation. This analysis suggests two directional extension of the Gatun-Chagres Basin; an east-west direction corresponding to the initial formation of the basin, and a modern northwest-southeast direction. To the northeast, gravity modeling indicates that there is a ~150 m-thick, Cretaceous-Holocene sedimentary basin present from Portobelo to Nombre de Dios. Sedimentary

  3. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard

    2005-04-15

    The principal research effort for the first six months of Year 2 of the project has been petroleum system characterization. Understanding the burial and thermal maturation histories of the strata in the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas is important in petroleum system characterization. The underburden and overburden rocks in these basins and subbasins are a product of their rift-related geohistory. Petroleum source rock analysis and thermal maturation and hydrocarbon expulsion modeling indicate that an effective regional petroleum source rock in the onshore interior salt basins, the North Louisiana Salt Basin, Mississippi Interior Salt Basin, Manila Subbasin and Conecuh Subbasin, was the Upper Jurassic Smackover lime mudstone. The Upper Cretaceous Tuscaloosa shale was an effective local petroleum source rock in the Mississippi Interior Salt Basin and a possible local source bed in the North Louisiana Salt Basin. Hydrocarbon generation and expulsion was initiated in the Early Cretaceous and continued into the Tertiary in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin. Hydrocarbon generation and expulsion was initiated in the Late Cretaceous and continued into the Tertiary in the Manila Subbasin and Conecuh Subbasin. Reservoir rocks include Jurassic, Cretaceous and Tertiary siliciclastic and carbonate strata. Seal rocks include Jurassic, Cretaceous and Tertiary anhydrite and shale beds. Petroleum traps include structural and combination traps.

  4. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2005-10-28

    The principal research effort for Year 2 of the project has been petroleum system characterization and modeling. Understanding the burial, thermal maturation, and hydrocarbon expulsion histories of the strata in the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas is important in hydrocarbon resource assessment. The underburden and overburden rocks in these basins and subbasins are a product of their rift-related geohistory. Petroleum source rock analysis and initial thermal maturation and hydrocarbon expulsion modeling indicated that an effective regional petroleum source rock in the onshore interior salt basins and subbasins, the North Louisiana Salt Basin, Mississippi Interior Salt Basin, Manila Subbasin and Conecuh Subbasin, was Upper Jurassic Smackover lime mudstone. The initial modeling also indicated that hydrocarbon generation and expulsion were initiated in the Early Cretaceous and continued into the Tertiary in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin and that hydrocarbon generation and expulsion were initiated in the Late Cretaceous and continued into the Tertiary in the Manila Subbasin and Conecuh Subbasin. Refined thermal maturation and hydrocarbon expulsion modeling and additional petroleum source rock analysis have confirmed that the major source rock in the onshore interior salt basins and subbasins is Upper Jurassic Smackover lime mudstone. Hydrocarbon generation and expulsion were initiated in the Early to Late Cretaceous and continued into the Tertiary.

  5. Field based geothermal exploration: Structural controls in the Tarutung Basin/North Central Sumatra (Indonesia)

    Science.gov (United States)

    Nukman, M.; Moeck, I.

    2012-04-01

    The Tarutung Basin is one of several basins along the prominent Sumatra Fault System (SFS) which represents a dextral strike slip fault zone segmented into individual fault strands. The basins are located at right-stepping transfer. The Tarutung Basin hosts geothermal manifestations such as hot springs and travertines indicating a geothermal system with some decent potential in the subsurface. As part of geothermal exploration, field geology is investigated focusing on how the structural setting controls the thermal manifestation distribution. A complex fault pattern is now newly mapped and evidences sinistral faults striking E-W (Silangkitang), normal faults striking SE-NW at the eastern strand of Tarutung Basin (Sitompul) and normal faults striking NW-SE at the western strand of the basin (Sitaka). These structures form an angle greater than 450 with respect to the current maximum principal stress which is oriented in N-S. Secondary sinistral shear fractures identified as antithetic Riedel shears can be correlated with hot spring locations at Silangkitang, forming an angle of 500 with respect to the current maximum stress. A large angle of normal fault and antithetic Riedel shear trend with respect to the current maximum stress direction indicates that the structures have been rotated. Unidentified dextral strike slip faults might exist at the eastern strand of Tarutung Basin to accommodate the clockwise rotation between the eastern boundary of the basin and the NW-SE striking normal fault of Panabungan. Normal faults striking parallel with the SFS East of the basin are interpreted as dilatational jogs caused by the clockwise rotated block movement with respect to the NW-SE fault trend sinistral shear along ENE-WSW faults. Silicified pryroclastics in association with large discharge at hot springs at these NW-SE striking normal faults support this hypothesis. As proposed by Nivinkovich (1976) and Nishimura (1986) Sumatra has rotated 20° clockwise since the last

  6. Major Crustal Fault Zone Trends and Their Relation to Mineral Belts in the North-Central Great Basin, Nevada

    Science.gov (United States)

    Rodriguez, Brian D.; Sampson, Jay A.; Williams, Jackie M.

    2007-01-01

    The Great Basin physiographic province covers a large part of the western United States and contains one of the world's leading gold-producing areas, the Carlin Trend. In the Great Basin, many sedimentary-rock-hosted disseminated gold deposits occur along such linear mineral-occurrence trends. The distribution and genesis of these deposits is not fully understood, but most models indicate that regional tectonic structures play an important role in their spatial distribution. Over 100 magnetotelluric (MT) soundings were acquired between 1994 and 2001 by the U.S. Geological Survey to investigate crustal structures that may underlie the linear trends in north-central Nevada. MT sounding data were used to map changes in electrical resistivity as a function of depth that are related to subsurface lithologic and structural variations. Two-dimensional (2-D) resistivity modeling of the MT data reveals primarily northerly and northeasterly trending narrow 2-D conductors (1 to 30 ohm-m) extending to mid-crustal depths (5-20 km) that are interpreted to be major crustal fault zones. There are also a few westerly and northwesterly trending 2-D conductors. However, the great majority of the inferred crustal fault zones mapped using MT are perpendicular or oblique to the generally accepted trends. The correlation of strike of three crustal fault zones with the strike of the Carlin and Getchell trends and the Alligator Ridge district suggests they may have been the root fluid flow pathways that fed faults and fracture networks at shallower levels where gold precipitated in favorable host rocks. The abundant northeasterly crustal structures that do not correlate with the major trends may be structures that are open to fluid flow at the present time.

  7. Beyond Colorado's Front Range - A new look at Laramide basin subsidence, sedimentation, and deformation in north-central Colorado

    Science.gov (United States)

    Cole, James C.; Trexler, James H.; Cashman, Patricia H.; Miller, Ian M.; Shroba, Ralph R.; Cosca, Michael A.; Workman, Jeremiah B.

    2010-01-01

    This field trip highlights recent research into the Laramide uplift, erosion, and sedimentation on the western side of the northern Colorado Front Range. The Laramide history of the North Park?Middle Park basin (designated the Colorado Headwaters Basin in this paper) is distinctly different from that of the Denver basin on the eastern flank of the range. The Denver basin stratigraphy records the transition from Late Cretaceous marine shale to recessional shoreline sandstones to continental, fluvial, marsh, and coal mires environments, followed by orogenic sediments that span the K-T boundary. Upper Cretaceous and Paleogene strata in the Denver basin consist of two mega-fan complexes that are separated by a 9 million-year interval of erosion/non-deposition between about 63 and 54 Ma. In contrast, the marine shale unit on the western flank of the Front Range was deeply eroded over most of the area of the Colorado Headwaters Basin (approximately one km removed) prior to any orogenic sediment accumulation. New 40Ar-39Ar ages indicate the oldest sediments on the western flank of the Front Range were as young as about 61 Ma. They comprise the Windy Gap Volcanic Member of the Middle Park Formation, which consists of coarse, immature volcanic conglomerates derived from nearby alkalic-mafic volcanic edifices that were forming at about 65?61 Ma. Clasts of Proterozoic granite, pegmatite, and gneiss (eroded from the uplifted core of the Front Range) seem to arrive in the Colorado Headwaters Basin at different times in different places, but they become dominant in arkosic sandstones and conglomerates about one km above the base of the Colorado Headwaters Basin section. Paleocurrent trends suggest the southern end of the Colorado Headwaters Basin was structurally closed because all fluvial deposits show a northward component of transport. Lacustrine depositional environments are indicated by various sedimentological features in several sections within the >3 km of sediment

  8. Cenozoic stratigraphic development in the north Chilean forearc: Implications for basin development and uplift history of the Central Andean margin

    Science.gov (United States)

    Hartley, Adrian J.; Evenstar, Laura

    2010-11-01

    Analysis of the Cenozoic stratigraphic development of the forearc of northern Chile between 18°S and 23°30'S, allows constraints to be placed on the timing and nature of basin formation and the uplift history of the Central Andes. Chronostratigraphic charts have been constructed from 20 lithostratigraphic sections distributed throughout the forearc. Sections were taken from the Longitudinal Valley, Central Depression, Calama Basin, Salar de Atacama, Precordillera and the western flank of the Western Cordillera. Correlation and timing of events is largely based on the presence of dated volcanic horizons in all the studied sections. Three chronostratigraphic units are defined based upon the presence of regional unconformities. Deposition of the Late Eocene to Early Miocene chronostratigraphic unit (38-19 Ma) commenced across an irregular unconformity surface between ˜ 38 and 30 Ma with alluvial fan and fluvial sediments derived from the east interbedded with rhyolitic ignimbrites. Aggradation after 25 Ma resulted in development of a large broad basin over much of northern Chile that expanded eastwards through onlap onto basement. Deposition terminated around 19 Ma with the development of an angular unconformity over much, but not all of the study area. During deposition of the Early to Late Miocene chronostratigraphic unit (18-10 Ma) emergent volcanic source areas to the east provided catchments for large fluvial systems that drained westwards into endorheic ephemeral lacustrine basins. Fold growth affected sedimentation restricting accommodation space to small intra-thrust basins in the Precordillera and localised disruption and unconformity development in the Longitudinal Valley. The Late Miocene to present day chronostratigraphic unit (10-0 Ma) followed the development of a regional angular unconformity at 10 Ma. Sedimentation was restricted to a series of thrust-bounded endorheic basins in both the Central Depression and the Precordillera sourced from the east

  9. An integrated framework to assess adaptation options to climate change impacts in an irrigated basin in Central North Chile

    Science.gov (United States)

    Vicuna, S.; Melo, O.; Meza, F. J.; Alvarez, P.; Maureira, F.; Sanchez, A.; Tapia, A.; Cortes, M.; Dale, L. L.

    2013-12-01

    Future climate conditions could potentially affect water supply and demand on water basins throughout the world but especially on snowmelt-driven agriculture oriented basins that can be found throughout central Chile. Increasing temperature and reducing precipitation will affect both the magnitude and timing of water supply this part of the world. Different adaptation strategies could be implemented to reduce the impacts of such scenarios. Some could be incorporated as planned policies decided at the basin or Water Use Organization levels. Examples include changing large scale irrigation infrastructure (reservoirs and main channels) either physically or its operation. Complementing these strategies it is reasonable to think that at a disaggregated level, farmers would also react (adapt) to these new conditions using a mix of options to either modify their patterns of consumption (irrigation efficiency, crop mix, crop area reduction), increase their ability to access new sources of water (groundwater, water markets) or finally compensate their expected losses (insurance). We present a modeling framework developed to represent these issues using as a case study the Limarí basin located in Central Chile. This basin is a renowned example of how the development of reservoirs and irrigation infrastructure can reduce climate vulnerabilities allowing the economic development of a basin. Farmers in this basin tackle climate variability by adopting different strategies that depend first on the reservoir water volume allocation rule, on the type and size of investment they have at their farms and finally their potential access to water markets and other water supplies options. The framework developed can be used to study these strategies under current and future climate scenarios. The cornerstone of the framework is an hydrology and water resources model developed on the WEAP platform. This model is able to reproduce the large scale hydrologic features of the basin such as

  10. Holocene Paleoenvironment of the North-central Great Basin: Preliminary Results from Favre Lake, Northern Ruby Mountains, Nevada

    Science.gov (United States)

    Starratt, S.; Wahl, D.; Wan, E.; Anderson, L.; Wanket, J.; Olson, H.; Lloyd-Davies, T.; Kusler, J.

    2009-12-01

    Little is known about Holocene climate variability in north-central Nevada. This study aims to assess changes in watershed vegetation, fire history, lake levels and limnological conditions in order to understand secular to millennial-scale changes in regional climate. Favre Lake (2,899 m a.s.l.; 12 m deep; 7.7 hectares) is a flow-through lake in the northern Ruby Mountains. The primary sources of influent, both of which appear to be intermittent, are Castle Lake (2,989 m a.s.l.) and Liberty Lake (3,077 m a.s.l.). The bedrock of the three lake basins is early Paleozoic marble and Mesozoic granite and metamorphic rocks. Bathymetric maps and temperature, pH, salinity, and conductivity profiles have been generated for Favre Lake. Surface samples and a series of cores were also collected using a modified Livingstone piston corer. The presence of the Mazama ash in the basal sediment (~4 m below the sediment/water interface) indicates the record extends to ~7,700 cal yr B.P. Magnetic susceptibility (MS) and loss-on-ignition data indicate that the sediments in the lowest part of the core contain primary and reworked Mazama ash. About 2,000 years ago CaCO3 increased from 2 to 3% of the inorganic sediment. The upper 25 cm of the core are marked by an increase in MS which may indicate increased erosion due to grazing. Between about 7,700 and 6,000 cal yr B.P. the diatom flora is dominated by a diverse assemblage of benthic species. The remainder of the core is dominated by Fragilaria, suggesting that lake level rose and flooded the shelf that surrounds the depocenter of the lake. This is supported by changes in the abundance of the aquatic fern Isoetes. Pinus and Artemisia dominate the pollen record, followed by subordinate levels of Poaceae, Asteraceae, Amaranthaceae, and Sarcobatus. The late early Holocene (7,700-6,000 cal yr B.P.) is dominated by Pinus which is present in reduced amounts during the middle Holocene (6,000-3,000 cal yr B.P.) and then returns to dominance in

  11. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard

    2004-10-28

    The objectives of the study are: to perform resource assessment of the in-place deep (>15,000 ft) natural gas resource of the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas through petroleum system identification, characterization and modeling and to use the petroleum system based resource assessment to estimate the volume of the in-place deep gas resource that is potentially recoverable and to identify those areas in the interior salt basins with high potential to recover commercial quantities of the deep gas resource. The principal research effort for Year 1 of the project is data compilation and petroleum system identification. The research focus for the first nine (9) months of Year 1 is on data compilation and for the remainder of the year the emphasis is on petroleum system identification.

  12. The Early Miocene-Early Pliocene Vegetation and Climate Changes at the north to northwest Çankırı -Çorum Basin (Central Anatolian Plateau)

    Science.gov (United States)

    Atalar, Müge; Kováčová, Marianna; Sezgül Kayseri Ozer, Mine; Utescher, Torsten; Mazzini, Ilaria; Gliozzi, Elsa; Cosentino, Domenico

    2016-04-01

    The ALErT project targets on climate and tectonic hazards in the densely populated regions in the Central Anatolian Plateau (CAP), within the framework of the Marie Curie FP7-PEOPLE-2013-ITN program, The CAP extends in a wide area in between zone the Aegean extensional zone and Bitlis /Zagros compressional zone. Çankırı Basin (in the middle CAP) is a key to understand aridification plateau interior and it was a deep pelagic Basin from Late Cretaceous -Early Tertiary as a result of the closure of Neo- Tethyan till the Middle Eocene. North to south of the Çankırı Basin; the Plio - Quaternary Deǧim formation (fluvial deposits) consist of massive mudstones and sandstones and it unconformable overlies the Bozkır formation (lacustrine deposits). That is a Messinian succession mainly by a 200 m-thick cyclic sequence of continental gypsum layers, clays and sandy clays in gypsum with different thicknesses crops. Bozkır formation, the lower being the contact with the Süleymanlı formation. It is overlay the Tuǧlu formation with uncomformably, which is an Upper Miocene succession mainly composed of dark grey silty and organic rich clays. Following formation, which outcrops in the northwest of Çankırı basin, is Hançili formation. The unit is covered by grey sediments of the Hançili Formation, showing alternations of channel sandstones and clay stones over 100 m thick in Early - Middle Miocene in the Çankırı basin. In this study, samples were analyzed for biotic proxy data (palynology) to figure the paleo-environmental and paleoclimate changes. Additionally only for Bozkir formation (longest section in the study area) were sampled for geochemical (δ18O - δ13C isotopes analyses and CaCO3) analysis and the rest of the formations were interpreted using the previous study. In the most pollen spectra the herbs and shrubs prevail: in Deǧim formation (50%), in Bozkır formation (75%), in Süleymanlı formation (47%), in Tuǧlu formation (60%) and in Han

  13. RESOURCE ASSESSMENT OF THE IN-PLACE AND POTENTIALLY RECOVERABLE DEEP NATURAL GAS RESOURCE OF THE ONSHORE INTERIOR SALT BASINS, NORTH CENTRAL AND NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-04-16

    The University of Alabama and Louisiana State University have undertaken a cooperative 3-year, advanced subsurface methodology resource assessment project, involving petroleum system identification, characterization and modeling, to facilitate exploration for a potential major source of natural gas that is deeply buried (below 15,000 feet) in the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas. The project is designed to assist in the formulation of advanced exploration strategies for funding and maximizing the recovery from deep natural gas domestic resources at reduced costs and risks and with minimum impact. The results of the project should serve to enhance exploration efforts by domestic companies in their search for new petroleum resources, especially those deeply buried (below 15,000 feet) natural gas resources, and should support the domestic industry's endeavor to provide an increase in reliable and affordable supplies of fossil fuels. The principal research effort for Year 1 of the project is data compilation and petroleum system identification. The research focus for the first nine (9) months of Year 1 is on data compilation and for the remainder of the year the emphasis is on petroleum system identification. The objectives of the study are: to perform resource assessment of the in-place deep (>15,000 ft) natural gas resource of the onshore interior salt basins of the North Central and Northeastern Gulf of Mexico areas through petroleum system identification, characterization and modeling and to use the petroleum system based resource assessment to estimate the volume of the in-place deep gas resource that is potentially recoverable and to identify those areas in the interior salt basins with high potential to recover commercial quantities of the deep gas resource. The project objectives will be achieved through a 3-year effort. First, emphasis is on petroleum system identification and characterization in the

  14. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2006-09-30

    The objectives of the study were: (1) to perform resource assessment of the thermogenic gas resources in deeply buried (>15,000 ft) natural gas reservoirs of the onshore interior salt basins of the north central and northeastern Gulf of Mexico areas through petroleum system identification, characterization and modeling; and (2) to use the petroleum system based resource assessment to estimate the volume of the deep thermogenic gas resource that is available for potential recovery and to identify those areas in the interior salt basins with high potential for this thermogenic gas resource. Petroleum source rock analysis and petroleum system characterization and modeling, including thermal maturation and hydrocarbon expulsion modeling, have shown that the Upper Jurassic Smackover Formation served as the regional petroleum source rock in the North Louisiana Salt Basin, Mississippi Interior Salt Basin, Manila Subbasin and Conecuh Subbasin. Thus, the estimates of the total hydrocarbons, oil, and gas generated and expelled are based on the assumption that the Smackover Formation is the main petroleum source rock in these basins and subbasins. The estimate of the total hydrocarbons generated for the North Louisiana Salt Basin in this study using a petroleum system approach compares favorably with the total volume of hydrocarbons generated published by Zimmermann (1999). In this study, the estimate is 2,870 billion barrels of total hydrocarbons generated using the method of Schmoker (1994), and the estimate is 2,640 billion barrels of total hydrocarbons generated using the Platte River software application. The estimate of Zimmermann (1999) is 2,000 to 2,500 billion barrels of total hydrocarbons generated. The estimate of gas generated for this basin is 6,400 TCF using the Platte River software application, and 12,800 TCF using the method of Schmoker (1994). Barnaby (2006) estimated that the total gas volume generated for this basin ranges from 4,000 to 8,000 TCF. Seventy

  15. SHRIMP zircon dating and LA-ICPMS Hf analysis of early Precambrian rocks from drill holes into the basement beneath the Central Hebei Basin, North China Craton

    Institute of Scientific and Technical Information of China (English)

    Yusheng Wan; Runlong Fan; Huiyi Sun; Xianzheng Zhao; Zejiu Wang; Dunyi Liu; Alfred Kröner; Chunyan Dong; Hangqian Xie; Yuansheng Geng; Yuhai Zhang

    2014-01-01

    The Central Hebei Basin (CHB) is one of the largest sedimentary basins in the North China Craton, extending in a northeastesouthwest direction with an area of>350 km2. We carried out SHRIMP zircon dating, Hf-in-zircon isotopic analysis and a whole-rock geochemical study on igneous and metasedi-mentary rocks recovered from drill holes that penetrated into the basement of the CHB. Two samples of gneissic granodiorite (XG1-1) and gneissic quartz diorite (J48-1) have magmatic ages of 2500 and 2496 Ma, respectively. Their zircons also record metamorphic ages of 2.41e2.51 and w2.5 Ga, respec-tively. Compared with the gneissic granodiorite, the gneissic quartz diorite has higher SREE contents and lower Eu/Eu* and (La/Yb)n values. Two metasedimentary samples (MG1, H5) mainly contain w2.5 Ga detrital zircons as well as late Paleoproterozoic metamorphic grains. The zircons of different origins haveεHf (2.5 Ga) values and Hf crustal model ages ranging from 0 to 5 and 2.7 to 2.9 Ga, respectively. Therefore, w2.5 Ga magmatic and Paleoproterozoic metasedimentary rocks and late Neoarchean to early Paleoproterozoic and late Paleoproterozoic tectono-thermal events have been identified in the basement beneath the CHB. Based on regional comparisons, we conclude that the early Precambrian basement beneath the CHB is part of the North China Craton.

  16. The Central European Permian Basins; Rheological and structural controls on basin history and on inter-basin connectivity

    NARCIS (Netherlands)

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

    2014-01-01

    We analyse the relative importance of the major crustal-scale fault zones and crustal architecture in controlling basin formation, deformation and the structural connections between basins. The North and South Permian Basins of Central Europe are usually defined by the extend of Rotliegend sedimenta

  17. SHRIMP zircon dating and LA-ICPMS Hf analysis of early Precambrian rocks from drill holes into the basement beneath the Central Hebei Basin, North China Craton

    Directory of Open Access Journals (Sweden)

    Yusheng Wan

    2014-07-01

    Full Text Available The Central Hebei Basin (CHB is one of the largest sedimentary basins in the North China Craton, extending in a northeast–southwest direction with an area of >350 km2. We carried out SHRIMP zircon dating, Hf-in-zircon isotopic analysis and a whole-rock geochemical study on igneous and metasedimentary rocks recovered from drill holes that penetrated into the basement of the CHB. Two samples of gneissic granodiorite (XG1-1 and gneissic quartz diorite (J48-1 have magmatic ages of 2500 and 2496 Ma, respectively. Their zircons also record metamorphic ages of 2.41–2.51 and ∼2.5 Ga, respectively. Compared with the gneissic granodiorite, the gneissic quartz diorite has higher ΣREE contents and lower Eu/Eu* and (La/Ybn values. Two metasedimentary samples (MG1, H5 mainly contain ∼2.5 Ga detrital zircons as well as late Paleoproterozoic metamorphic grains. The zircons of different origins have εHf (2.5 Ga values and Hf crustal model ages ranging from 0 to 5 and 2.7 to 2.9 Ga, respectively. Therefore, ∼2.5 Ga magmatic and Paleoproterozoic metasedimentary rocks and late Neoarchean to early Paleoproterozoic and late Paleoproterozoic tectono-thermal events have been identified in the basement beneath the CHB. Based on regional comparisons, we conclude that the early Precambrian basement beneath the CHB is part of the North China Craton.

  18. Interaction of water components in the semi-arid Huasco and Limarí river basins, North Central Chile

    Directory of Open Access Journals (Sweden)

    G. Strauch

    2009-10-01

    Full Text Available For sustainable water resource management in semi-arid regions, sound information is required about interactions between the different components of the water system: rain/snow precipitation, surface/subsurface run-off, groundwater recharge. Exemplarily, the Huasco and Limarí river basins as water stressed river catchments have been studied by isotope and hydrochemical methods for (i the origin of water, (ii water quality, (iii relations of surface and groundwater.

    Applying the complex multi-isotopic and hydrochemical methodology to the water components of the Huasco and Limarí basins, a differentiation of water components concerning subsurface flow and river water along the catchment area and by anthropogenic impacts are detected. Sulphate and nitrate concentrations indicate remarkable input from mining and agricultural activities along the river catchment.

    The 2H-18O relations of river water and groundwater of both catchments point to the behaviour of river waters originated in an arid to semi-arid environment.

    Consequently, the groundwater from several production wells in the lower parts of the catchments is related to the rivers where the wells located, however, it can be distinguished from the river water. Using the hydrological water balance and the isotope mixing model, the interaction between surface and subsurface flows and river flow is estimated.

  19. Structural imprints at the front of the Chocó-Panamá indenter: Field data from the North Cauca Valley Basin, Central Colombia

    Science.gov (United States)

    Suter, F.; Sartori, M.; Neuwerth, R.; Gorin, G.

    2008-11-01

    The northern Andes are a complex area where tectonics is dominated by the interaction between three major plates and accessory blocks, in particular, the Chocó-Panamá and Northern Andes Blocks. The studied Cauca Valley Basin is located at the front of the Chocó-Panamá Indenter, where the major Romeral Fault System, active since the Cretaceous, changes its kinematics from right-lateral in the south to left-lateral in the north. Structural studies were performed at various scales: DEM observations in the Central Cordillera between 4 and 5.7°N, aerial photograph analyses, and field work in the folded Oligo-Miocene rocks of the Serranía de Santa Barbara and in the flat-lying, Pleistocene Quindío-Risaralda volcaniclastic sediments interfingering with the lacustrine to fluviatile sediments of the Zarzal Formation. The data acquired allowed the detection of structures with a similar orientation at every scale and in all lithologies. These families of structures are arranged similarly to Riedel shears in a right-lateral shear zone and are superimposed on the Cretaceous Romeral suture. They appear in the Central Cordillera north of 4.5°N, and define a broad zone where 060-oriented right-lateral distributed shear strain affects the continental crust. The Romeral Fault System stays active and strain partitioning occurs among both systems. The southern limit of the distributed shear strain affecting the Central Cordillera corresponds to the E-W trending Garrapatas-Ibagué shear zone, constituted by several right-stepping, en-échelon, right-lateral, active faults and some lineaments. North of this shear zone, the Romeral Fault System strike changes from NNE to N. Paleostress calculations gave a WNW-ESE trending, maximum horizontal stress, and 69% of compressive tensors. The orientation of σ1 is consistent with the orientation of the right-lateral distributed shear strain and the compressive state characterizing the Romeral Fault System in the area: it bisects the

  20. Resource Assessment of the In-Place and Potentially Recoverable Deep Natural Gas Resource of the Onshore Interior Salt Basins, North Central and Northeastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2006-04-26

    The principal research effort for the first half of Year 3 of the project has been resource assessment. Emphasis has been on estimating the total volume of hydrocarbons generated and the potential amount of this resource that is classified as deep (>15,000 ft) gas in the North Louisiana Salt Basin, the Mississippi Interior Salt Basin, the Manila Subbasin and the Conecuh Subbasin. The amount of this resource that has been expelled, migrated and entrapped is also the focus of the first half of Year 3 of this study.

  1. Transient shortening strain across an active extensional fault, Basin and Range Province, north-central Nevada, USA, based on geodetic and paleoseismologic data.

    Science.gov (United States)

    Friedrich, A.; Wernicke, B.; Lee, J.; Sieh, K.

    2003-04-01

    The northern Basin and Range province is one of the largest continental extensional regions on earth. At 40 degrees N latitude, the province is 800 km wide and consists of 15 and 20 N-S striking normal faults. These faults accommodated mainly east-west directed extension of tens of kilometers since Mid-Miocene time and recent geodetic surveys show that extension is still active today at a rate of ~1.5 cm/yr across the province (e.g., Bennett et al. 2000; Thatcher et al. 1999). The distribution of this geodetically measurable strain accumulation within the province, however, contradicts geologic observations across some of the active normal faults. For example, coordinated geologic and geodetic measurements across the Crescent Valley fault (CVF), north-central Nevada, reveal a profound mismatch in deformation rates. Since 1996, the two ranges on either side of the CVF have been moving toward each other at ca. 2 mm/yr, indicating shortening. In contrast, new reconnaissance mapping and paleoseismological analyses along the CVF also indicate that this fault is one of the more active normal faults of the Basin and Range province. The 50 km long Cortez Mountains range front is characterized by relief of up to 1.3 km, steep (up to 36 degrees) triangular facets, and young (late Pleistocene to late Holocene) alluvial fans cut by normal fault scarps. Vertical displacement across the CVF is ca. 3 km; since 15 Ma the average long-term vertical displacement rate is ca. 0.2 mm/yr. Topographic profiling shows that fault scarps, 2-7 m high, are the result of a single rupture event and cut late Holocene alluvial fans. A trench across a faulted alluvial fan at Fourmile Canyon reveals a vertical displacement of 4.5 m distributed across two normal faults. 14C analyses on charcoal from a buried offset surface in the hanging wall of the trench and from the base of the overlying colluvial wedge tightly bracket the age of the most recent earthquake to between 2.8 +- 0.1 and 2.7 +- 0.1 ka

  2. East Central Uplift Belt of Junggar Basin

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ Mosuowandong ( Z3 ) and Dongdaohaizi (Z4) are two bidding blocks located in the east part of central uplift Belt, the hinterland of Junggar Basin. Xinjiang Uygur Autonomous Region. It totally covers an area of 8 100km2. Topographically, the two blocks are quite gentle with elevation of 380-400 m on average. The north part is desert and the south area is good for farming. There are three ephemeral streams flowing across the desert from south to north. The ground water is buried at the depth ranging from 6 to 8 m. It belongs to continental climate with the annually averaged precipitation of 80 mm. The traffic is rather convenient in the south part of both blocks. There are several sand-paved roads and two asphalt roads connected with the highway from Karamay to Urumqi City.

  3. Vulnerability in north- central Vietnam

    DEFF Research Database (Denmark)

    Casse, Thorkil; Milhøj, Anders; Nguyen, Thao Phuong

    2015-01-01

    This article examines changes in livelihood strategies in response to flooding. It does so on the basis of a household survey which was undertaken in three provinces in north central Vietnam. All households in the survey were regularly affected by flooding, but only poor households experience...

  4. Mesozoic basins and associated palaeogeographic evolution in North China

    Institute of Scientific and Technical Information of China (English)

    Yong-Qing Liu; Hong-Wei Kuang; Nan Peng; Huan Xu; Peng Zhang; Neng-Sheng Wang; Wei An

    2015-01-01

    In North China, the Mesozoic terrestrial basins, sedimentary palaeogeography and tectonic settings involved ifve evolutionary stages:(1) the Early-Middle Triassic, (2) the Late Triassic to Early-Middle Jurassic, (3) the Late Jurassic to early Early Cretaceous, (4) the middle-late Early Cretaceous and (5) the Late Cretaceous. The regional punctuated tectonic events occurred during these evolutionary stages. During the Early-Middle Triassic (stage 1), the Xingmeng Orogenic Belt (XMOB, i.e., east-ern part of Central Asia Orogenic Belt, CAOB) of the northern North China was settled in the transition of tectonic environment from syn-orogenic compression to post-orogenic extension with intensive uplifting. It is a main provenance in the uniifed Ordos-North China Basin.The united continental plate of China and the Qinling-Dabie-Sulu Orogenic Belt formed due to convergence and collision between the North China Plate and the Yangtze Plate along two suture zones of the Mianlue and the Shangdan in the terminal Middle Triassic. During the Late Triassic to the Early-Middle Jurassic (stage 2), the Late Triassic maifc or alkaline rocks and intrusions occurred on the northern and southern margins of North China Craton (NCC) and XMOB, implying that intensiifed extension happened all over the North China (early phase of stage 2). Additionally, in the late phase of stage 2, the basic volcanic-iflling faulted basins were widely distributed in the northeastern North China during the Early-Middle Jurassic, including a series of small-to medium-sized basins with coal-bearing strata and some volcanic rocks in other areas of North China, which was the result of subduction of the Palaeo-Paciifc Plate during the Early-Middle Jurassic. An active continental margin with accretionary complex developed in the eastern Heilongjiang of China, Japan and the Far East of Russia at that time. However, in the end of the Early-Middle Jurassic, because of the Yan-shanian orogeny characterized by

  5. Tectonic and thermal history of the western Serrania del Interior foreland fold and thrust belt and Guarico Basin, north central Venezuela: Implications of new apatite fission track analysis and seismic interpretation

    Science.gov (United States)

    Perez de Armas, Jaime Gonzalo

    Structural analysis, interpretation of seismic reflection lines, and apatite fission-track analysis in the Western Serrania del Interior fold and thrust belt and in the Guarico basin of north-central Venezuela indicate that the area underwent Mesozoic and Tertiary-to-Recent deformation. Mesozoic deformation, related to the breakup of Pangea, resulted in the formation of the Espino graben in the southernmost portion of the Guarico basin and in the formation of the Proto-Caribbean lithosphere between the diverging North and South American plates. The northern margin of Venezuela became a northward facing passive margin. Minor normal faults formed in the Guarico basin. The most intense deformation took place in the Neogene when the Leeward Antilles volcanic island arc collided obliquely with South America. The inception of the basal foredeep unconformity in the Late Eocene-Early Oligocene marks the formation of a perisutural basin on top of a buried graben system. It is coeval with minor extension and possible reactivation of Cretaceous normal faults in the Guarico basin. It marks the deepening of the foredeep. Cooling ages derived from apatite fission-tracks suggest that the obduction of the fold and thrust belt in the study area occurred in the Late Oligocene through the Middle Miocene. Field data and seismic interpretations suggest also that contractional deformation began during the Neogene, and specifically during the Miocene. The most surprising results of the detrital apatite fission-track study are the ages acquired in the sedimentary rocks of the easternmost part of the study area in the foreland fold and thrust belt. They indicate an Eocene thermal event. This event may be related to the Eocene NW-SE convergence of the North and South American plates that must have caused the Proto-Caribbean lithosphere to be shortened. This event is not related to the collision of the arc with South America, as the arc was far to the west during the Eocene.

  6. Late Mesozoic and Cenozoic thermotectonic evolution of the central Brooks Range and adjacent North Slope foreland basin, Alaska: Including fission track results from the Trans-Alaska Crustal Transect (TACT)

    Science.gov (United States)

    O'Sullivan, P. B.; Murphy, J.M.; Blythe, A.E.

    1997-01-01

    Apatite fission track data are used to evaluate the thermal and tectonic history of the central Brooks Range and the North Slope foreland basin in northern Alaska along the northern leg of the Trans-Alaska Crustal Transect (TACT). Fission track analyses of the detrital apatite grains in most sedimentary units resolve the timing of structures and denudation within the Brooks Range, ranging in scale from the entire mountain range to relatively small-scale folds and faults. Interpretation of the results indicates that rocks exposed within the central Brooks Range cooled rapidly from paleotemperatures 110?? to 50??C during discrete episodes at ???100??5 Ma, ???60??4 Ma, and ???24??3 Ma, probably in response to kilometer-scale denudation. North of the mountain front, rocks in the southern half of the foreland basin were exposed to maximum paleotemperatures 110??C in the Late Cretaceous to early Paleocene as a result of burial by Upper Jurassic and Cretaceous sedimentary rocks. Rapid cooling from these elevated paleotemperatures also occurred due to distinct episodes of kilometer-scale denudation at ???60??4 Ma, 46??3 Ma, 35??2 Ma, and ???24??3 Ma. Combined, the apatite analyses indicate that rocks exposed along the TACT line through the central Brooks Range and foreland basin experienced episodic rapid cooling throughout the Late Cretaceous and Cenozoic in response to at least three distinct kilometer-scale denudation events. Future models explaining orogenic events in northern Alaska must consider these new constraints from fission track thermochronology. Copyright 1997 by the American Geophysical Union.

  7. Natural factors and mining activity bearings on the water quality of the Choapa basin, North Central Chile: insights on the role of mafic volcanic rocks in the buffering of the acid drainage process.

    Science.gov (United States)

    Parra, Amparo; Oyarzún, Jorge; Maturana, Hugo; Kretschmer, Nicole; Meza, Francisco; Oyarzún, Ricardo

    2011-10-01

    This contribution analyzes water chemical data for the Choapa basin, North Central Chile, for the period 1980-2004. The parameters considered are As, Cu Fe, pH, EC, SO₄⁻², Cl⁻¹, and HCO[Formula: see text], from samples taken in nine monitoring stations throughout the basin. Results show rather moderate contents of As, Cu, and Fe, with the exception of the Cuncumén River and the Aucó creek, explained by the influence of the huge porphyry copper deposit of Los Pelambres and by the presence of mining operations, respectively. When compared against results obtained in previous researches at the neighboring Elqui river basin, which host the El Indio Au-Cu-As district, a much reduced grade of pollution is recognized for the Choapa basin. Considering the effect of acid rock drainage (ARD)-related Cu contents on the fine fraction of the sediments of both river basins, the differences recorded are even more striking. Although the Los Pelambres porphyry copper deposit, on the headwaters of the Choapa river basin, is between one and two orders of magnitude bigger than El Indio, stream water and sediments of the former exhibit significantly lower copper contents than those of the latter. A main factor which may explain these results is the smaller degree of H( + )-metasomatism on the host rocks of the Los Pelambres deposit, where mafic andesitic volcanic rocks presenting propylitic hydrothermal alteration are dominant. This fact contrast with the highly altered host rocks of El Indio district, where most of them have lost their potential to neutralize ARD.

  8. REE Compositions of Lower Ordovician Dolomites in Central and North Tarim Basin, NW China: A Potential REE Proxy for Ancient Seawater

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xuefeng; HU Wenxuan; JIN Zhijun; ZHANG Juntao; QIAN Yixiong; ZHU Jingquan; ZHU Dongya; WANG Xiaolin; XIE Xiaomin

    2008-01-01

    Rare earth dement compositions of Lower Ordovician dolomites in the Central and Northern Tarim Basin are studied. Most dolomite samples are more or less contaminated by clay minerals. Their rare earth element compositions have been consequently changed, showing both seawater-like and non-seawater-like features. The clay contamination should be disposed before the REE data are used. Through ICP-MS and ICP-AES analyses, the REE features are well documented. The clay contamination is quantitatively determined by microscopic investigation, trace elements and REE contents. The dolomites, at least in the Tarim Basin, are thought to be pure when their total LREE contents are less than 3x10-6. Through comparison, the pure dolomites show similarities in REE patterns but differences in REE contents with co-existing pure limestone, which indicates that dolomitization may slightly change the REE compositions. Nevertheless, whatever the change is, the pure dolomites may act as a potential REE proxy for Ordovician seawater, which would be significant for ancient massive dolomite strata that lack limestone.

  9. Tectonic types of deepwater basins and structural segmentation of the North Atlantic

    Science.gov (United States)

    Pushcharovsky, Yu. M.

    2012-03-01

    Typification of tectonic structures is one of the important lines of tectonic research. Recently, I have published several articles, which are concerned with deepwater oceanic basins. This paper is focused on tectonic typification of deepwater basins of the North Atlantic. They are attributed to three types: perispreading, central thalassogenic, and pericontinental. The first type comprises the Irminger, Iceland, Greenland, and Lofoten basins. The first two basins are associated with the Reykjanes Ridge and the two others, with the Mohns Ridge. The central thalassogenic type is exemplified in the Norwegian Basin, while the pericontinental type in the Rockall Trough. Two systems of basins are distinguished by morphostructural and historical-geological features: the northern system of the Oligocene-Quaternary structures and the southern system of the Paleocene-Quaternary structures. The Greenland-Faroe tectonovolcanic zone serves as their tectonic interface. In the tectonic typology of their deepwater basins, the North Atlantic is closer to the Indian than to other oceans. The present-day configuration of the northern basins is determined by neotectonics. The tectonic movements in the northern system of basins at this stage were more contrasting than in the southern system. This explains the greater depth of the former basins. The spatial position of the deepwater basins belonging to different types determines the tectonic segmentation of the oceanic bottom. The southern, central, and northern latitudinal segments correspond to different geodynamic states of the Earth's interior.

  10. Tectonic control on turbiditic sedimentation: The Late Cretaceous-Eocene successions in the Sinop-Boyabat Basin of north-central Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Janbu, Nils Erik

    2004-07-01

    The aim of this study: Tectonics is widely recognized by geologists as the single most important factor controlling the development, filling and deformation of sedimentary basins. In general terms, the role of tectonics seems rather ''obvious'' to most geologists, because we know reasonably well as what tectonics ''can do'' as the agent of structural deformation. Therefore, the role of tectonics is often invoked as a kind of ballpark variable - as the obvious cause of ''subsidence'' or ''uplift'' - and seems to some authors even too obvious to mention. Relatively little attempt has been in sedimentological and stratigraphic studies to recognize as to what effects exactly the tectonic activity had on sedimentation in a particular basin. The principal aim of the present study has been to improve our understanding of how tectonic activity can affect deep-water turbiditic sedimentation in a particular basin, including its ''external'' influences (basin geometry, basin-margin configuration, sediment source/supply and relative sea-level change) and ''internal'' effects (basin-floor subsidence, seafloor deformation). Foreland basins are some of the most active tectonically, and the Sinop- Boyabat Basin is a fascinating case of a rift converted into a foreland basin and increasingly deformed. Summary of papers: The main part of the field study, concerned with the sedimentology and facies analysis of the turbiditic succession, is summarized in Papers 1-3, which put special emphasis on the physical character and morphodynamic evolution of the depositional systems and on the tectonic control on their development. Paper 4 focuses on the frequency distribution of bed thickness data collected by detailed logging of various turbiditic assemblages: siliciclastic deposits of nonchannelized currents (lobe and overbank facies); siliciclastic deposits of poorly

  11. Tectonic control on turbiditic sedimentation: The Late Cretaceous-Eocene successions in the Sinop-Boyabat Basin of north-central Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Janbu, Nils Erik

    2004-07-01

    The aim of this study: Tectonics is widely recognized by geologists as the single most important factor controlling the development, filling and deformation of sedimentary basins. In general terms, the role of tectonics seems rather ''obvious'' to most geologists, because we know reasonably well as what tectonics ''can do'' as the agent of structural deformation. Therefore, the role of tectonics is often invoked as a kind of ballpark variable - as the obvious cause of ''subsidence'' or ''uplift'' - and seems to some authors even too obvious to mention. Relatively little attempt has been in sedimentological and stratigraphic studies to recognize as to what effects exactly the tectonic activity had on sedimentation in a particular basin. The principal aim of the present study has been to improve our understanding of how tectonic activity can affect deep-water turbiditic sedimentation in a particular basin, including its ''external'' influences (basin geometry, basin-margin configuration, sediment source/supply and relative sea-level change) and ''internal'' effects (basin-floor subsidence, seafloor deformation). Foreland basins are some of the most active tectonically, and the Sinop- Boyabat Basin is a fascinating case of a rift converted into a foreland basin and increasingly deformed. Summary of papers: The main part of the field study, concerned with the sedimentology and facies analysis of the turbiditic succession, is summarized in Papers 1-3, which put special emphasis on the physical character and morphodynamic evolution of the depositional systems and on the tectonic control on their development. Paper 4 focuses on the frequency distribution of bed thickness data collected by detailed logging of various turbiditic assemblages: siliciclastic deposits of nonchannelized currents (lobe and overbank facies); siliciclastic deposits of poorly

  12. Ferrobasalts from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Mukhopadhyay, R.; Popko, D.C.

    The occurrence of ferrobasalts recovered from the Central Indian Ocean Basin crust generated at the Southeast Indian Ridge during a phase of moderate to fast spreading accretion (approx 110-190 mm/yr, full rate) is reported. FeO (13-19%), and Ti...

  13. Assessment of undiscovered shale gas and shale oil resources in the Mississippian Barnett Shale, Bend Arch–Fort Worth Basin Province, North-Central Texas

    Science.gov (United States)

    Marra, Kristen R.; Charpentier, Ronald R.; Schenk, Christopher J.; Lewan, Michael D.; Leathers-Miller, Heidi M.; Klett, Timothy R.; Gaswirth, Stephanie B.; Le, Phuong A.; Mercier, Tracey J.; Pitman, Janet K.; Tennyson, Marilyn E.

    2015-12-17

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated mean volumes of 53 trillion cubic feet of shale gas, 172 million barrels of shale oil, and 176 million barrels of natural gas liquids in the Barnett Shale of the Bend Arch–Fort Worth Basin Province of Texas.

  14. Structural Architecture and Evolution of Kumkuli Basin, North Tibet

    Institute of Scientific and Technical Information of China (English)

    He Bizhu; Xu Zhiqin; Jiao Cunli; Cui Junwen; Wang Shenglang; Wang Gonghuai; Li Zhaoyang; Qiu Zhuli

    2009-01-01

    Utilizing the new data of gravity, magnetic, and magnetotelluric survey, we analyzed the characteristics of the three geophysical attribute (gravity, magnetic, and resistivity) interfaces and the deep architecture and structure of Kumkuli basin. The research results can provide basic data for early basin structural study. From coupled basin and mountain system, analysis of the structure, and evolution of Knmknli basin, we found that there was zoning from north to south and from west to east. Kumkuli basin has three structural architecture layers including metamorphic crystallization basement, fold basement and sedimentary cover. Knmkuli basin can be divided into three structural units, two depressions, and one uplift. Structural evolution of the Kumkuli basin can be divided into five evolution stages, including Kumkuli microcontinent formed in Sinian-Ordovician, suture around Kumkuli basin formed in Eopaleozoic, retroarc foreland basin formed in Neopaleozoic, rejuvenated foreland hasin developed in Mesozoic, and strike slip and compression basin developed in Cenozoic.

  15. Salt movements within the Central European basin system

    Energy Technology Data Exchange (ETDEWEB)

    Maystrenko, Yuriy; Bayer, Ulf; Scheck-Wenderoth [GeoForschungsZentrum (GFZ), Potsdam (Germany); Littke, Ralf [RWTH Aachen (Germany). Lehrstuhl fuer Geologie, Geochemie und Lagerstaetten des Erdoels und der Kohle

    2010-04-15

    Evolution of salt structures in relation to tectonic events within central part of the Central European Basin System is described by summarizing results which have been obtained and published in frame of the research project DFG-SPP 1135. These results illustrate main phases of salt tectonics within the basin system from the Triassic to present day. During the Buntsandstein and Muschelkalk, extension triggered raft tectonics and salt movements within the Ems Trough, the Glueckstadt and the Horn Grabens. The next phase of salt movements occurred in response to a Middle-Late Keuper regional extensional event which was strongest within the Triassic depocenters of the Central European Basin System, such as the Horn Graben, the Glueckstadt Graben, the Ems and the Rheinsberg Troughs. Regional erosion truncated the study area during the Late Jurassic-Early Cretaceous time. The magnitude of Late Jurassic-Early Cretaceous erosion is declining towards southern margin of the basin system where a dextral transtensional regime was established in the Lower Saxony Basin and neighboring areas during the Late Jurassic-Early Cretaceous. The late Early Cretaceous-early Late Cretaceous is characterized by a relative tectonic quiescence without strong salt movements. The Late Cretaceous-Early Cenozoic inversion provocated renewed salt movements, causing the thick-skinned salt tectonics along the Elbe Fault System and the thin-skinned character of salt movements towards the north from the area of strain localisation. Post-inversion Cenozoic subsidence was accompanied by salt movements, related either to diapiric rise due to regional shortening and/or to local almost E-W directed extension. (orig.)

  16. Hydrocarbon Potential of Pre-cenozoic Strata in the North Yellow Sea Basin

    Institute of Scientific and Technical Information of China (English)

    CAI Feng; DAI Chunshan; CHEN Jianwen; LI Gang; SUN Ping

    2005-01-01

    The North Yellow Sea Basin ( NYSB ), which was developed on the basement of North China (Huabei) continental block, is a typical continental Mesozoic-Cenozoic sedimentary basin in the sea area. Its Mesozoic basin is a residual basin,below which there is probably a larger Paleozoic sedimentary basin. The North Yellow Sea Basin comprises four sags and three uplifts. Of them, the eastern sag is a Mesozoic-Cenozoic sedimentary sag in NYSB and has the biggest sediment thickness; the current Korean drilling wells are concentrated in the eastern sag. This sag is comparatively rich in oil and gas resources and thus has a relatively good petroleum prospect in the sea.The central sag has also accommodated thick Mesozoic-Cenozoic sediments. The latest research results show that there are three series of hydrocarbon source rocks in the North Yellow Sea Basin, namely, black shales of the Paleogene, Jurassic and Cretaceous. The principal hydrocarbon source rocks in NYSB are the Mesozoic black shale. According to the drilling data of Korea, the black shales of the Paleogene,Jurassic and Cretaceous have all come up to the standards of good and mature source rocks. The NYSB owns an intact system of oil generation, reservoir and capping rocks that can help hydrocarbon to form in the basin and thus it has the great potential of oil and gas. The vertical distribution of the hydrocarbon resources is mainly considered to be in the Cretaceous and then in the Jurassic.

  17. Ground-water use, locations of production wells, and areas irrigated using ground water in 1998, middle Humboldt River basin, north-central Nevada

    Science.gov (United States)

    Plume, Russell W.

    2003-01-01

    In 1998, ground water was being pumped from about 420 production wells in the middle Humboldt River Basin for a variety of uses. Principal uses were for agriculture, industry, mining, municipal, and power plant purposes. This report presents a compilation of the number and types of production wells, areas irrigated by ground water, and ground-water use in 14 hydrographic areas of the middle Humboldt River Basin in 1998. Annual pumping records for production wells usually are reported to the Nevada Division of Water Resources. However, operators of irrigation wells are not consistently required to report annual pumpage. Daily power-consumption and pump-discharge rates measured at 20 wells during the 1998 irrigation season and total power use at each well were used to estimate the amount of water, in feet of depth, applied to 20 alfalfa fields. These fields include about 10 percent of the total area, 36,700 acres, irrigated with ground water in the middle Humboldt River Basin. In 1998 an average of 2.0 feet of water was applied to 14 fields irrigated using center-pivot sprinkler systems, and an average of 2.6 feet of water was applied to 6 fields irrigated using wheel-line sprinkler systems. A similar approach was used to estimate the amount of water pumped at three wells using pumps powered by diesel engines. The two fields served by these three wells received 3.9 feet of water by flood irrigation during the 1998 irrigation season. The amount of water applied to the fields irrigated by center-pivot and wheel-line irrigation systems during the 1998 irrigation season was less than what would have been applied during a typical irrigation season because late winter and spring precipitation exceeded long-term monthly averages by as much as four times. As a result, the health of crops was affected by over-saturated soils, and most irrigation wells were only used sporadically in the first part of the irrigation season. Power consumption at 19 of the 20 wells in the 1994

  18. Thermal Evolution of the North-Central Gulf Coast

    Science.gov (United States)

    Nunn, Jeffrey A.; Scardina, Allan D.; Pilger, Rex H., Jr.

    1984-12-01

    The subsidence history of the North Louisiana Salt Basin, determined from well data, indicates that the region underwent extension during rifting and has since passively subsided due to conductive cooling of the lithosphere. Timing of the rifting event is consistent with opening of the Gulf of Mexico during Late Triassic to Early Jurassic time. Crustal extension by a factor of 1.5 to 2 was computed from "tectonic" subsidence curves. However, data from the early subsidence history are insufficient to distinguish between uniform and nonuniform extension of the lithosphere. The magnitude of extension is in good agreement with total sediment and crustal thicknesses from seismic refraction data in the adjacent Central Mississippi Salt Basin. The temperature distribution within the sediments is calculated using a simple heat conduction model. Temperature and subsidence effects of thermal insulation by overlying sediments are included. The computed temperature distribution is in good agreement with bottom hole temperatures measured in deep wells. Temperature histories predicted for selected stratigraphic horizons within the North Louisiana Salt Basin suggest that thermal conditions have been favorable for hydrocarbon generation in the older stata. Results from a two-dimensional heat conduction model suggest that a probable cause for the early formation of the adjacent uplifts is lateral heat conduction from the basin. Rapid extension of the lithosphere underneath areas with horizontal dimensions of 50-100 km produces extremely rapid early subsidence due to lateral heat conduction. The moderate subsidence rate observed in the North Louisiana Salt Basin during the Jurassic and Early Cretaceous suggests slow extension over a long period of time.

  19. Pull-apart origin of the Satpura Gondwana basin, central India

    Indian Academy of Sciences (India)

    Chandan Chakraborty; Sanjoy Kumar Ghosh

    2005-06-01

    The Gondwana basins of peninsular India are traditionally considered as extensional-rift basins due to the overwhelming evidence of fault-controlled synsedimentary subsidence. These basins indeed originated under a bulk extensional tectonic regime, due to failure of the attenuated crust along pre-existing zones of weakness inherited from Precambrian structural fabrics. However, disposition of the basins and their structural architecture indicate that the kinematics of all the basins cannot be extensional. To maintain kinematic compatibility with other basins as well as the bulk lateral extension, some basins ought to be of strike-slip origin. The disposition, shape and structural architecture of the Satpura basin, central India suggest that the basin could be a pull-apart basin that developed above a releasing jog of a left-stepping strike-slip fault system defined by the Son-Narmada south fault and Tapti north fault in consequence to sinistral displacement along WSW-ENE. Development of a sedimentary basin under the above-mentioned kinematic condition was simulated in model experiments with sandpack. The shape, relative size, stratigraphic and structural architecture of the experimental basin tally with that of the Satpura basin. The experimental results also provide insights into the tectono-sedimentary evolution of the Satpura basin in particular and pull-apart basins in general.

  20. THE LICHENS OF NORTH CENTRAL OKLAHOMA

    Directory of Open Access Journals (Sweden)

    DARVIN WENDELL KECK

    2006-12-01

    Full Text Available Over 1,000 specimens of lichens were collected at 78 collecting stations in 11 counties of North Central Oklahoma during 1959 and 1960. The objectives were to identify lichens collected in the area; to establish a record of lichen distribution for each county in the area; and to analyze the ecological relationships.

  1. Ferromanganese nodules from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Jauhari, P.; Pattan, J.N.

    In order to delineate a mine site for ferromanganese nodules, extensive surveys were conducted in Central Indian Ocean Basin. Mapping of the basin by multibeam swath bathymetry (Hydrosweep) has revealed many new bottom relief features...

  2. Landslide Inventory for the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This geodatabase is an inventory of existing landslides in the Little North Santiam River Basin, Oregon (2009). Each landslide feature shown has been classified...

  3. North Park Basin, Colorado, for 1999 National Coal Resource Assessment

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This ArcView shapefile contains a polygon representing the extent of the North Park coal basin boundary. This theme was created specifically for the National Coal...

  4. The Australian central Eromanga Basin project: An introduction

    Science.gov (United States)

    Moss, F. J.; Wake-Dyster, K. D.

    1983-12-01

    The Australian Bureau of Mineral Resources is carrying out a major multidisciplinary program of geological and geophysical studies in southwestern Queensland in cooperation with the Geological Survey of Queensland. The project is aimed at providing information on the regional structure and depositional history of the central Eromanga Basin and the underlying Adavale, Cooper and Galilee basins. The information being obtained is particularly relevant to a better understanding of the petroleum prospectivity of the area. The program includes geophysical surveys involving 1400 km of new six-fold CDP seismic reflection coverage on regional traverses up to 400 km long crossing the main structural elements of the area; gravity measurements along all new seismic reflection traverses; refraction surveys along two major east-west and north-south traverses and magnetotelluric soundings along the same major east-west traverse. LANDSAT imagery studies are providing new perspective on many regional structures when used in conjunction with seismic and gravity information. Wireline logs and synthetic seismograms are being used with the new seismic data to re-examine stratigraphic correlations. Palynologic and lithologic studies are underway to assist in determining depositional environments. Source rock, maturation, hydrological and geochemical studies are providing information on the generation and migration of hydrocarbons. A significant feature of the program is the extension of the recording time of all new reflection data to 20 s to obtain good quality deep crustal reflection information comparable to that obtained on COCORP programs in the United States. The reflection data is being interpreted with the refraction, gravity and magnetotelluric data to investigate the relationship of deep crustal and upper mantle features to the sedimentary basins in the central Eromanga Basin area.

  5. New insights into the North Taranaki Basin from New Zealand's first broadband 3D survey

    Science.gov (United States)

    Uzcategui, Marjosbet; Francis, Malcolm; Kong, Wai Tin Vincent; Patenall, Richard; Fell, Dominic; Paxton, Andrea; Allen, Tristan

    2016-06-01

    The Taranaki Basin is the only hydrocarbon producing basin in New Zealand. The North Taranaki Basin has widespread two-dimensional (2D) seismic coverage and numerous wells that have not encountered commercial accumulations. This is attributed to the structural complexity in the central graben and the absence of necessary information to help understand the basin's evolution. An active petroleum system has been confirmed by hydrocarbon shows and non-commercial oil and gas discoveries (Karewa-1 and Kora-1). A broadband long offset three-dimensional (3D) seismic survey was acquired and processed by Schlumberger in 2013 to evaluate the hydrocarbon potential of the North Taranaki Basin. Innovative acquisition techniques were combined with advanced processing and imaging methods. Raypath distortions and depth uncertainty were significantly reduced by processing through tilted transverse isotropy (TTI) anisotropic Kirchhoff prestack depth migration with a geologically constrained velocity model. The survey provided the necessary information to understand the petroleum system and provide evidence for material hydrocarbon accumulations. In this investigation, we assessed the hydrocarbon potential of the North Taranaki Basin using the newly acquired data. 3D seismic interpretation and amplitude-versus-offset (AVO) analysis support the renewed potential of the basin and demonstrate effectiveness of these technologies that together can achieve encouraging results for hydrocarbon exploration.

  6. Miocene sediments distribution in the central and northern parts of the Vienna Basin, central Europe

    Science.gov (United States)

    Lee, E.; Wagreich, M.; Decker, K.

    2012-12-01

    The Vienna Basin is a Miocene sedimentary basin situated at the Alpine-Carpathian transition and spreading from Austria in the South to the Czech Republic and Slovakia in the north. The basin primarily developed as a piggy-back basin during the Lower Miocene (~18 - 16 Ma) on top of the NW-ward moving Eastern Alpine and West Carpathians thrust sheets. In the late Lower Miocene, the local stress regime changed by the lateral extrusion of the Eastern Alps towards the Pannonian area. It leads to the developing of the basin between two left stepping sinistral strike-slip faults of the Vienna Basin faults system during the Middle and Upper Miocene (~16 - 8 Ma). Structures related with this pull-apart stage are extensional sinistral strike-slip duplexes connected with large scale listric normal fraults. Our study area mainly covers the central and northern Vienna Basin that is not yet studied well for the stratigraphy. The goal of this study is the characterization and distribution of the Miocene sediments. For this purpose we investigated approximately 200 wells in 17 well-groups in order to obtain details on the Miocene sediments. Among them 84 wells drilled down to the Northern Calcareous Alps and the flysch units in the pre-Neogene basin subcrop. The initial phase of the Miocene deposition was related to the transgression and is characterized by the deposition of coarse clastic and marly clay sediments. These sediments are distributed locally in the northern part of the basin. The overlying sediments are more widely distributed than the underlying ones. During the late Lower Miocene, the depocenters shifted towards the south and sedimentation was dominated by marly clay intercalated with sand. An unconformity depicted for the regional stage boundary fits well with the regressive phase and the subsequent transgression. From Middle to Upper Miocene, sediments were deposited over a wide area of the Vienna Basin. The sedimentation was governed by combination of pull

  7. Detailed bathymetric surveys in the central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Kodagali, V.N.; KameshRaju, K.A.; Ramprasad, T.; George, P.; Jaisankar, S.

    Over 420,000 line kilometers of echo-sounding data was collected in the Central Indian Basin. This data was digitized, merged with navigation data and a detailed bathymetric map of the Basin was prepared. The Basin can be broadly classified...

  8. Paleogene Sediment Character of Mountain Front Central Sumatra Basin

    Directory of Open Access Journals (Sweden)

    P. A. Suandhi

    2014-07-01

    Full Text Available DOI: 10.17014/ijog.v8i3.164The SE-NW trending Mountain Front of Central Sumatra Basin is located in the southern part of the basin. The Mountain Front is elongated parallel to the Bukit Barisan Mountain, extending from the Regencies of North Padang Lawas (Gunung Tua in the northwest, Rokan Hulu, Kampar, Kuantan Singingi, and Inderagiri Hulu Regency in the southeast. The Palaeogene sediments also represent potential exploration objectives in Central Sumatra Basin, especially in the mountain front area. Limited detailed Palaeogene sedimentology information cause difficulties in hydrocarbon exploration in this area. Latest age information and attractive sediment characters based on recent geological fieldwork (by chaining method infer Palaeogene sediment potential of the area. The Palaeogene sedimentary rock of the mountain front is elongated from northwest to southeast. Thickness of the sedimentary unit varies between 240 - 900 m. Palynology samples collected recently indicate that the oldest sedimentary unit is Middle Eocene and the youngest one is Late Oligocene. This latest age information will certainly cause significant changes to the existing surface geological map of the mountain front area. Generally, the Palaeogene sediments of the mountain front area are syn-rift sediments. The lower part of the Palaeogene deposit consists of fluvial facies of alluvial fan and braided river facies sediments. The middle part consists of fluvial meandering facies, lacustrine delta facies, and turbidity lacustrine facies sediments. The upper part consists of fluvial braided facies and transitional marine facies sediments. Volcanism in the area is detected from the occurrence of volcanic material as lithic material and spotted bentonite layers in the middle part of the mountain front area. Late rifting phase is indicated by the presence of transitional marine facies in the upper part of the Palaeogene sediments.

  9. Miocene transgression in the central and eastern parts of the Sivas Basin (Central Anatolia, Turkey) and the Cenozoic palaeogeographical evolution

    Science.gov (United States)

    Poisson, André; Vrielynck, Bruno; Wernli, Roland; Negri, Alessandra; Bassetti, Maria-Angela; Büyükmeriç, Yesim; Özer, Sacit; Guillou, Hervé; Kavak, Kaan S.; Temiz, Haluk; Orszag-Sperber, Fabienne

    2016-01-01

    We present here a reappraisal of the tectonic setting, stratigraphy and palaeogeography of the central part of the Sivas Basin from Palaeocene to late Miocene. The Sivas Basin is located in the collision zone between the Pontides (southern Eurasia) and Anatolia (a continental block rifted from Gondwana). The basin overlies ophiolites that were obducted onto Anatolia from Tethys to the north. The Central Anatolian Crystalline Complex (CACC) experienced similar ophiolite obduction during Campanian time, followed by exhumation and thrusting onto previously emplaced units during Maastrichtian time. To the east, crustal extension related to exhumation of the CACC created grabens during the early Tertiary, including the Sivas Basin. The Sivas Basin underwent several tectonic events during Paleogene-Neogene. The basin fill varies, with several sub-basins, each being characterised by a distinctive sequence, especially during Oligocene and Miocene. Evaporite deposition in the central part of the basin during early Oligocene was followed by mid-late Oligocene fluvio-lacustrine deposition. The weight of overlying fluvial sediments triggered salt tectonics and salt diapir formation. Lacustrine layers that are interbedded within the fluviatile sediments have locally yielded charophytes of late Oligocene age. Emergent areas including the pre-existing Sivas Basin and neighbouring areas were then flooded from the east by a shallow sea, giving rise to a range of open-marine sub-basins, coralgal reef barriers and subsiding, restricted-marine sub-basins. Utilising new data from foraminifera, molluscs, corals and nannoplankton, the age of the marine transgression is reassessed as Aquitanian. Specifically, age-diagnostic nannoplankton assemblages of classical type occur at the base of the transgressive sequence. However, classical stratigraphic markers have not been found within the planktic foraminiferal assemblages, even in the open-marine settings. In the restricted-marine sediments

  10. Tectono-stratigraphic evolution of an inverted extensional basin: the Cameros Basin (north of Spain)

    Science.gov (United States)

    Omodeo Salè, Silvia; Guimerà, Joan; Mas, Ramón; Arribas, José

    2014-09-01

    The Cameros Basin is a part of the Mesozoic Iberian Rift. It is an extensional basin formed during the late Jurassic and early Cretaceous, in the Mesozoic Iberian Rift context, and it was inverted in the Cenozoic as a result of the Alpine contraction. This work aims to reconstruct the tectono-stratigraphic evolution of the basin during the Mesozoic, using new and revised field, geophysical and subsurface data. The construction of a basin-wide balanced section with partial restorations herein offers new insights into the geometry of the syn-rift deposits. Field data, seismic lines and oil well data were used to identify the main structures of the basin and the basin-forming mechanisms. Mapping and cross-sectional data indicate the marked thickness variation of the depositional sequences across the basin, suggesting that the extension of the depositional area varied during the syn-rift stage and that the depocentres migrated towards the north. From field observation and seismic line interpretation, an onlap of the depositional sequences to the north, over the marine Jurassic substratum, can be deduced. In the last few decades, the structure and geometry of the basin have been strongly debated. The structure and geometry of the basin infill reconstructed herein strongly support the interpretation of the Cameros Basin as an extensional-ramp synclinal basin formed on a blind south-dipping extensional ramp. The gradual hanging-wall displacement to the south shifted the depocentres to the north over time, thus increasing the basin in size northwards, with onlap geometry on the pre-rift substratum. The basin was inverted by means of a main thrust located in a detachment located in the Upper Triassic beds (Keuper), which branched in depth with the Mesozoic extensional fault flat. The reconstruction of the tectono-stratigraphic evolution of the Cameros Basin proposed herein represents a synthesis and an integration of previous studies of the structure and geometry of the

  11. Soil indigenous knowledge in North Central Namibia

    Science.gov (United States)

    Prudat, Brice; Bloemertz, Lena; Kuhn, Nikolaus J.

    2016-04-01

    Mapping and classifying soils is part of an important learning process to improve soil management practices, soil quality and increase productivity. In order to assess soil quality improvement related to an ongoing land reform in North-Central Namibia, the characteristics that determine soil quality in the local land use context were determined in this study. To do so, we collated the indigenous soil knowledge in North-Central Namibia where the Ovakwanyama cultivate pearl millet for centuries. Local soil groups are defined mostly based on their productivity potential, which varies depending on the rainfall pattern. The morphological criteria used by the farmers to differentiate the soil groups (colour, consistence) were supported by a conventional analysis of soil physical and chemical properties. Now, they can be used to develop a soil quality assessment toolbox adapted to the regional use. The characteristics of the tool box do not directly indicate soil quality, but refer to local soils groups. The quality of these groups is relatively homogenous at the local scale. Our results show that understanding of indigenous soil knowledge has great potential to improve soil quality assessment with regards to land use. The integration of this knowledge with the conventional soil analysis improves the local meaning of such a "scientific" assessment and thus facilitates dialog between farmers and agronomists, but also scientists working in different regions of the world, but in similar conditions. Overall, the integration of indigenous knowledge in international classification systems (e.g. WRB) as attempted in this study has thus a major potential to improve soil mapping in the local context.

  12. Buried nodules and associated sediments from the central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R.; Iyer, S.D.; Dutta, P.

    Buried nodules from siliceous sediments in the central Indian Basin are morphologically variable and mineralogically consist of d-MnO2 incipient todorokite. Compositionally they are weakly diagenetic. The sediment coarse fractions ( 63 mu m...

  13. New occurrences of Australasian microtektites in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    ShyamPrasad, M.

    Thirty-three microtektites have been recovered from four different sites in the Central Indian Basin. Based on their physical properties, geographical occurrence and chemical composition, they are identified as belonging to the Australasian tektite...

  14. Geologic framework, age, and lithologic characteristics of the North Park Formation in North Park, north-central Colorado

    Science.gov (United States)

    Shroba, Ralph R.

    2016-10-18

    Deposits of the North Park Formation of late Oligocene and Miocene age are locally exposed at small, widely spaced outcrops along the margins of the roughly northwest-trending North Park syncline in the southern part of North Park, a large intermontane topographic basin in Jackson County in north-central Colorado. These outcrops suggest that rocks and sediments of the North Park Formation consist chiefly of poorly consolidated sand, weakly cemented sandstone, and pebbly sandstone; subordinate amounts of pebble conglomerate; minor amounts of cobbly pebble gravel, siltstone, and sandy limestone; and rare beds of cobble conglomerate and altered tuff. These deposits partly filled North Park as well as a few small nearby valleys and half grabens. In North Park, deposits of the North Park Formation probably once formed a broad and relatively thick sedimentary apron composed chiefly of alluvial slope deposits (mostly sheetwash and stream-channel alluvium) that extended, over a distance of at least 150 kilometers (km), northwestward from the Never Summer Mountains and northward from the Rabbit Ears Range across North Park and extended farther northwestward into the valley of the North Platte River slightly north of the Colorado-Wyoming border. The maximum preserved thickness of the formation in North Park is about 550 meters near the southeastern end of the North Park syncline.The deposition of the North Park Formation was coeval in part with local volcanism, extensional faulting, development of half grabens, and deposition of the Browns Park Formation and Troublesome Formation and was accompanied by post-Laramide regional epeirogenic uplift. Regional deposition of extensive eolian sand sheets and loess deposits, coeval with the deposition of the North Park Formation, suggests that semiarid climatic conditions prevailed during the deposition of the North Park Formation during the late Oligocene and Miocene.The North Park Formation locally contains a 28.1-mega-annum (Ma

  15. 75 FR 64691 - North Central Idaho Resource Advisory Committee

    Science.gov (United States)

    2010-10-20

    ... Forest Service North Central Idaho Resource Advisory Committee AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The North Central Idaho RAC will meet in Potlatch, Idaho. The committee is.... (PST). ADDRESSES: The meeting will be held at the Potlatch Public Library, 1010 Onaway Road,...

  16. 12 Blocks Open in North west China's Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    PetroChina Foreign Cooperation Administration Depa

    2006-01-01

    @@ After having opened up for 20 years, the field of oil/gas exploration and development in China is witnessing a new round of high tide to attract foreign investment.PetroChina, China's biggest oil/gas producer and supplier,decided to offer 12 blocks totaling an acreage of 110,000sq.km. in Tarim Basin to players of the industry globally.The project is the biggest oil/gas deal in China aiming at foreign cooperation for approximately 12 years, in which the 12 blocks that will be offered located mainly in southwestern, central and eastern Tarim Basin. It will enable PetroChina to combine its experience and cognition on the geological condition of Tarim Basin with the updated prospecting concept and advanced prospecting technique in the world, improve the proved degree of oil and gas resources in Tarim Basin and achieve a big breakthrough in oil and gas exploration.

  17. Strain localisation during basin inversion in the North German basin and the Donbas Fold Belt

    Energy Technology Data Exchange (ETDEWEB)

    Maystrenko, Y.; Bayer, U. [GFZ Potsdam (Germany); Gajewski, D. [Hamburg Univ. (Germany). Inst. fuer Geophysik

    2007-09-13

    The DEKORP Basin'96 and the DOBREflection-200 lines provide two world wide exceptional examples of successfully performed deep seismic lines. This is especially true for the inversion of the two basins by representing probably two stages in the amount of shortening accompanied by strain localization causing decoupling of the sedimentary fill from the deeper crust within the North East German basin and the Donbas Fold Belt. High-velocity bodies are observed in the DEKORP Basin'96 and DOBREflection-2000 reflection seismic lines. These bodies may have been essential in localizing strain localisation by counteracting compressive forces and causing folding and finally failure and faulting of the deep crust. (orig.)

  18. Petroleum geology and resources of the North Caspian Basin, Kazakhstan and Russia

    Science.gov (United States)

    Ulmishek, Gregory F.

    2001-01-01

    The North Caspian basin is a petroleum-rich but lightly explored basin located in Kazakhstan and Russia. It occupies the shallow northern portion of the Caspian Sea and a large plain to the north of the sea between the Volga and Ural Rivers and farther east to the Mugodzhary Highland, which is the southern continuation of the Ural foldbelt. The basin is bounded by the Paleozoic carbonate platform of the Volga-Ural province to the north and west and by the Ural, South Emba, and Karpinsky Hercynian foldbelts to the east and south. The basin was originated by pre-Late Devonian rifting and subsequent spreading that opened the oceanic crust, but the precise time of these tectonic events is not known. The sedimentary succession of the basin is more than 20 km thick in the central areas. The drilled Upper Devonian to Tertiary part of this succession includes a prominent thick Kungurian (uppermost Lower Permian) salt formation that separates strata into the subsalt and suprasalt sequences and played an important role in the formation of oil and gas fields. Shallow-shelf carbonate formations that contain various reefs and alternate with clastic wedges compose the subsalt sequence on the 1 basin margins. Basinward, these rocks grade into deep-water anoxic black shales and turbidites. The Kungurian salt formation is strongly deformed into domes and intervening depressions. The most active halokinesis occurred during Late Permian?Triassic time, but growth of salt domes continued later and some of them are exposed on the present-day surface. The suprasalt sequence is mostly composed of clastic rocks that are several kilometers thick in depressions between salt domes. A single total petroleum system is defined in the North Caspian basin. Discovered reserves are about 19.7 billion barrels of oil and natural gas liquids and 157 trillion cubic feet of gas. Much of the reserves are concentrated in the supergiant Tengiz, Karachaganak, and Astrakhan fields. A recent new oil discovery

  19. On Restoring Sedimentary Basins for Post-Depositional Deformation - Paleozoic Basins of the Central Andes

    Science.gov (United States)

    Bahlburg, H.

    2015-12-01

    The reconstruction and interpretation of sedimentary basins incorporated into folded and thrusted mountain belts is strongly limited by the style and intensity of shortening. This problem is exacerbated if deformation is polyphasic as is the case for the Paleozoic basins in the central Andes. Some of these have been deformed by folding and thrusting during at least 3 events in the Late Ordovician, the Late Paleozoic and Cenozoic. A realistic reconstruction of the original basin dimensions and geometries from outcrops and maps appears to be almost impossible. We present results of a stepwise reconstruction of the Paleozoic basins of the central Andes by restoring basin areas and fills accounting for crustal shortening. The structurally most prominent feature of the central Andes is the Bolivian Orocline which accomodated shortening in the last 45 Ma on the order of between 300 and 500 km. In a first step basins were restored by accounting for Cenozoic rotation and shortening by deconvolving the basins using an enhanced version of the oroclinal bending model of Ariagada et al. (2008). Results were then restored stepwise for older deformation. Constraints on these subsequent steps are significantly poorer as values of shortening can be derived only from folds and thusts apparent in outcrops. The amount of shortening accomodated on unexposed and therefore unknown thrusts can not be quantified and is a significant source of error very likely leading to an underestimation of the amount of shortening. Accepting these limitations, basin restoration results in an increase in basin area by ≥100%. The volumes of stratigraphically controlled basin fills can now be redistributed over the wider, restored area, translating into smaller rates of accumulation and hence required subsidence. The restored rates conform to those of equivalent modern basin settings and permit a more realistic and actualistic analysis of subsidence drivers and the respective tectonic framework.

  20. Development of basins in the Inner Moray Firth and the North Sea by crustal extension and dextral displacement of the Great Glen Fault

    Science.gov (United States)

    McQuillin, R.; Donato, J. A.; Tulstrup, J.

    1982-08-01

    Reflection seismic data provide evidence that Mesozoic dextral movements along the Great Glen Fault line have had an important influence on the development of the Inner Moray Firth Basin. Geophysical evidence further indicates that deep structure beneath the inner basin is dissimilar to that beneath the outer part and Viking and Central Grabens in the North Sea. Tectonic development of the inner basin can nevertheless be fitted into a pattern of North Sea extensional movements which led to the formation of the graben system with which the major North Sea hydrocarbon resources are associated.

  1. Conductivity models for the North Perth Basin, Western Australia

    Science.gov (United States)

    Hoskin, T. E.; Regenauer-Lieb, K.; Jones, A. G.

    2013-12-01

    Exploration for geothermal resources in the North Perth basin, Western Australia, led to acquisition of new, high resolution Magnetotelluric (MT) and Audio-Magnetotelluric (AMT) data, the first of its kind in the area. Electromagnetic (EM) techniques are widely used in geothermal exploration and ground water investigations and they are well suited for application in the Perth basin. Two east-west transects investigating the structure of the onshore basin and its eastern margin, the Darling Fault Zone, are compared with existing geological models and geophysical data. Down-hole temperature data and depth-to-basement models were used to define areas of investigation in the basin, but there are limited geophysical data available. 1D, 2D and 3D modeling of electromagnetic data have been used to produce new conductivity models using existing data to constrain modelling. EM data complement existing gravity and seismic data and support published models in the upper 4-6km. However in deeper parts of the basin, MT data provide additional information allowing for revision of depth-to-basement. In addition to this, we clearly identify a conductivity anomaly associated with the Darling Fault Zone and are able to image this anomaly penetrating into the upper mantle. Fault zone conductors have been imaged on other lithosphere faults around the world, with one explanation being fluids in the enhanced permeability of the damage zone. Evidence to explain the fault zone conductor of the Darling Fault is presented and discussed as it could have significant implications in the identification of new areas, prospective for geothermal resources in the basin.

  2. The Mesozoic rift basins of eastern North America: Potential reservoir or Explorationist's folly

    Energy Technology Data Exchange (ETDEWEB)

    Pyron, A.

    1991-08-01

    Mesozoic rift basins are found on the East Coast of North America from Georgia to Nova Scotia. The basins formed as a result of extensional activity associated with the breakup of Pangaea. The internal geometry of the basins includes a depositional sequence ranging from coarse fanglomerates to fine-grained siltstones and argillites. Since these Mesozoic rift basins were first studied, they have not been considered to be likely spots for hydrocarbon accumulations. Recently, geologists have reconsidered these Mesozoic basins and have developed a more synergistic approach that suggests that many of these rift basins might be suitable targets for exploration. By analogy, these Mesozoic basins are correlative to similar basins in northwestern Africa, where significant reserved of oil and natural gas have been developed. The similarity between the productive basins in northwestern Africa and the Mesozoic basins of North America and their proximity to major markets provides sufficient rationale to further investigate these basins.

  3. Division of Hydrocarbon Plays and Resources Evaluation in the North Ustyurt Basin,Central Asia%中亚北乌斯丘尔特盆地成藏组合划分与资源潜力评价

    Institute of Scientific and Technical Information of China (English)

    余一欣; 殷进垠; 郑俊章; 李锋; 陶崇智; 徐小龙; 吴航

    2016-01-01

    Based on the integrated analysis of the basic geological features an d oil and gas fields distribution, and cored by reservoirs,seven hydrocarbon plays are divided in the Eocene,Lower Cretaceous,Middle and Lower Jurassic,and Carboniferous reservoirs in the North Ustyurt basin.The undiscovered recoverable petrole-um resources of the plays have also been reevaluated by the Monte Carlo method.The result reveals that the to-tal amount of the undiscovered resources is about 2 102 MMboe,of which oil is 1 201 MMbbl and gas is 5 406 Bcf.Geological risks evaluation of key elements including reservoirs,traps,migration and preservation have also been completed.Then,the seven hydrocarbon plays are ranked by the double factors method of resources-risks.According to the classification criterion,there are one Ⅰ-class play,one Ⅱb-class play,two Ⅲ-class plays,two Ⅳa-class plays and one Ⅳc-class play in the North Ustyurt basin.The most favorable exploration ob-jectives in the Mesozoic should be faulted anticlinal traps in the northern slope and on the top of the North Buza-chi uplift,where the Paleozoic Bashkirian and Asselian carbonate reservoirs may also have potentials.In addi-tion,it is hopeful to find oil and gas reserves in the local Eocene and Middle Jurassic sandstone and the Carboni-ferous Visean carbonate reservoirs in the eastern basin.%根据北乌斯丘尔特盆地主要地质特征和油气聚集规律,并以储集层为核心,在始新统、下白垩统、中侏罗统、下侏罗统和石炭系等储集层内划分出7个成藏组合。然后采用蒙特卡洛模拟法对不同成藏组合中的石油和天然气的待发现可采资源量分别进行模拟计算。结果表明,北乌斯丘尔特盆地待发现可采资源量可达2102 MMboe,其中石油为1201 MMbbl,天然气为5406 Bcf。同时参考对储层、圈闭、运移和保存等成藏要素的地质风险评价结果,应用资源-地质风险概率双因素法进行有利区

  4. Ferromanganese oxides on sharks' teeth from Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.

    The mineralogy, composition and growth rates of ferromanganese (Fe-Mn) oxides over the sharks' teeth from the Central Indian Ocean Basin are presented. The trends of metal enrichment (Mn, Ni, Cu and Zn) and depletion (Fe and Co), the Mn/Fe ratio...

  5. Delaware basin/Central basin platform margin: The development of a subthrust deep-gas province in the Permian Basin

    Energy Technology Data Exchange (ETDEWEB)

    Purves, W.J. (Mobil Oil Corp., Midland, TX (USA)); Ting, S.C. (Mobil, Farmers Branch, TX (USA))

    1990-05-01

    A deep-gas-prone province was identified along the Delaware basin/Central Basin platform margin, a margin conventionally interpreted to be bounded by high-angle normal or high-angle reverse structures. Redefinition of the tectonic style between the Delaware basin and the adjacent platform resulted in the identification of this Delaware basin/Central Basin platform subthrust province and a giant prospect within it. Definition of a giant-sized gas prospect in northern Pecos County, Texas, revealed that portions of this margin may be characterized by shingled, low-angle, eastward-dipping, basement involved thrust faults. Interpretations suggest that hidden, subthrust footwall structures may trend discontinuously for greater than 100 mi along this structural margin. Subthrust footwall structures formed as basinal buttress points for the Central Basin platform to climb over the Delaware basin. In this area, structural relief of over 19,000 ft over a 10-mi width is believed due to stacking of low-angle thrust sheets. Seismic resolution of this subthrust margin has been complexed by allochtonous hanging-wall gravity-glide blocks and folds and by velocity changes in overlying syn- and posttectonic sediments associated with basin-to-shelf lithofacies changes. Statistical studies indicate that this deep-gas province has a play potential of greater than 10 tcf of gas, with individual prospect sizes exceeding 1 tcfg. The prospects defined along this trend are deep (approximately 20,000 ft) subthrust structural traps that are indigenously sourced and reservoired by dual-matrix porosity. Vitrinite supported maturation modeling suggests that these subthrust structures formed prior to catagenic conversion of the oldest source rocks to oil and later to gas. Tectonically fractured Ordovician Ellenburger and Devonian sediments are considered the principal reservoirs. Shales overlying reservoir intervals form vertical seals.

  6. Deep crustal reflection results from the central Eromanga Basin, Australia

    Science.gov (United States)

    Mathur, S. P.

    1983-12-01

    From 1980 to 1982 deep seismic reflection profiles were recorded across the central Eromanga Basin in eastern Australia to study the regional structure, stratigraphy and geological history of the Eromanga Basin and infra-basins. The reflection data were recorded to 20 s to obtain additional information on the nature and structure of the crust below the sediments and their relationship to the development of the basins. The seismic sections show good quality reflections from the deep crust as well as from the sedimentary layers. Based on the character, strength, coherence, continuity and spatial distribution of the reflections, the sections can be divided into four zones. The tope zone between 0 and 2.5 s shows fairly uniform, coherent and continuous events which correlate with the Mesozoic and Late Palaeozoic sediments. The zone from 2.5 to 8 s (4 to 22 km) does not show any primary reflections and is interpreted as the highly-deformed metasedimentary and metavolcanic rocks of the Early Palaeozoic Thomson Orogen underlying the sediments. Without any recognisable reflection or diffraction patterns in this zone, it is difficult to say whether the faulting and folding observed in the sediments extend into the upper crustal basement. The deeper zone of numerous reflection segments between 8 and 12.5 s (22 to 36 km) is interpreted as thin laminae of alternating low and high velocity (intermediate and basic) rocks, and correlates with the lower crust bounded by refraction velocity discontinuities. The lowest zone of no reflections below 12.5 s corresponds with the upper mantle. The reflection character and thickness as well as the refraction velocity structure of the crust under the central Eromanga Basin area are significantly different from those of the Precambrian crust under the Georgina Basin to the northwest. It is proposed that the crust under the Eromanga Basin is extensionally attenuated crust which had been intruded by sills of basaltic melt from the underlying

  7. Recent glacier variations at the Aconcagua basin, central Chilean Andes

    Science.gov (United States)

    Bown, Francisca; Rivera, Andrés; Acuña, César

    The majority of glaciers in central Chile have receded in recent decades, from >50 m to only a few meters per year, mainly in response to an increase in the 0°C isotherm altitude. The Aconcagua river basin (33° S) is one of the major glaciated basins in central Chile, with 121 km2 of ice in 2003. An earlier inventory using 1955 aerial photographs yielded a total surface area of 151 km2, implying a reduction in glacier area of 20% (0.63 km2 a-1) over the 48 years. Photographic stereo models, high-resolution satellite images (Landsat, ASTER) and SRTM data have been used to delineate glacier basins. A focus on Glaciar Juncal Norte, one of the largest glaciers in the basin, allows a more detailed analysis of changes. The glacier has exhibited a smaller reduction (14%) between 1955 and 2006, and the resulting elevation changes over this smaller period are not significant. The above reduction rates are lower than in other glaciers of central Chile and Argentina. This trend emphasizes water runoff availability in a river where most of the water in the dry summers is generated by glaciers and snowpack, and where most of the superficial water rights are already allocated. Ongoing hydrological research including modelling of future water runoff will improve our understanding.

  8. Magnetotelluric Data, North Central Yucca Flat, Nevada Test Site, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    J.M. Williams; B.D. Rodriguez, and T.H. Asch

    2005-11-23

    Nuclear weapons are integral to the defense of the United States. The U.S. Department of Energy, as the steward of these devices, must continue to gauge the efficacy of the individual weapons. This could be accomplished by occasional testing at the Nevada Test Site (NTS) in Nevada, northwest of Las Vegas. Yucca Flat Basin is one of the testing areas at the NTS. One issue of concern is the nature of the somewhat poorly constrained pre-Tertiary geology and its effects on ground-water flow in the area subsequent to a nuclear test. Ground-water modelers would like to know more about the hydrostratigraphy and geologic structure to support a hydrostratigraphic framework model that is under development for the Yucca Flat Corrective Action Unit (CAU). During 2003, the U.S. Geological Survey (USGS) collected and processed Magnetotelluric (MT) and Audio-magnetotelluric (AMT) data at the Nevada Test Site in and near Yucca Flat to help characterize this pre-Tertiary geology. That work will help to define the character, thickness, and lateral extent of pre-Tertiary confining units. In particular, a major goal has been to define the upper clastic confining unit (UCCU) in the Yucca Flat area. Interpretation will include a three-dimensional (3-D) character analysis and two-dimensional (2-D) resistivity model. The purpose of this report is to release the MT sounding data for north central Yucca Flat, Profile 7, as shown in Figure 1. No interpretation of the data is included here.

  9. Palaeoenvironmental changes across the Danian–Selandian boundary in the North Sea Basin

    DEFF Research Database (Denmark)

    Clemmensen, Anne; Thomsen, Erik

    2005-01-01

    and eastern part of the North Sea Basin resulted in a huge influx of reworked Cretaceous chalk and an almost complete stop of carbonate production. Finally, later in the early Selandian, in connection to a general sea-level rise and a reduction in the gateway between the North Sea Basin and the Tethys Sea...

  10. Suggestion of a dynamic model of North China basin-range system

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    It is found from preliminary studies that previous basin-range models have difficulties in explaining the formation of the Mesozoic North-China basin-range system. This work suggests a new model-"tectonic thermal erosion" model, which considers the North China basin of Late Mesozoic and its peripheral ranges as a unified system, identifies relationship between upwelling and lateral spreading of the asthenolith with horizontal movement and deformation of the upper crust in the system, clarifies the effects of underplating erosion on the crustal evolution, and tries to establish an earth-dynamic model of the North China Mesozoic basin-range supported by numerical simulation.

  11. Surface waters of North Boggy Creek basin in the Muddy Boggy Creek basin in Oklahoma

    Science.gov (United States)

    Laine, L.L.

    1958-01-01

    Analysis of short-term streamflow data in North Boggy Creek basin indicates that the average runoff in this region is substantial. The streamflow is highly variable from year to year and from month to month. The estimated total yield from the North Boggy Creek watershed of 231 square miles averages 155,000 acre-feet annually, equivalent to an average runoff depth of 12 1/2 inches. Almost a fourth of the annual volume is contributed by Chickasaw Creek basin, where about 35,000 acre-feet runs off from 46 square miles. Two years of records show a variation in runoff for the calendar year 1957 in comparison to 1956 in a ratio of 13 to 1 for the station on North Boggy Creek and a ratio of 18 to 1 for the station on Chickasaw Creek. In a longer-term record downstream on Muddy Boggy Creek near Farris, the corresponding range was 17 to 1, while the calendar years 1945 and 1956 show a 20-fold variation in runoff. Within a year the higher runoff tends to occur in the spring months, April to June, a 3-month period that, on the average, accounts for at least half of the annual flow. High runoff may occur during any month in the year, but in general, the streamflow is relatively small in the summer. Records for the gaging stations noted indicate that there is little or no base flow in the summer, and thus there will be periods of no flow at times in most years. The variation in runoff during a year is suggested by a frequency analysis of low flows at the reference station on Muddy Boggy Creek near Farris. Although the mean flow at that site is 955 cfs (cubic feet per second), the median daily flow is only 59 cfs and the lowest 30-day flow in a year will average less than 1 cfs in 4 out of 10 years on the average. The estimated mean flow on North Boggy Creek near Stringtown is 124 cfs, but the estimated median daily flow is only 3 1/2 cfs. Because of the high variability in streamflow, development of storage by impoundment will be necessary to attain maximum utilization of the

  12. New insights into the earliest Quaternary environments in the Central North Sea from 3D seismic

    Science.gov (United States)

    Lamb, Rachel; Huuse, Mads; Stewart, Margaret; Brocklehurst, Simon H.

    2014-05-01

    In the past the transition between an unconformable surface in the south to a conformable horizon towards the north has made identification and mapping the base-Quaternary in the central North Sea difficult (Sejrup et al 1991; Gatliff et al 1994). However recent integration of biostratigraphy, pollen analysis, paleomagnetism and amino acid analysis in the Dutch and Danish sectors (Rasmussen et al 2005; Kuhlmann et al 2006) has allowed greater confidence in the correlation to the region 3D seismic datasets and thus has allowed the base-Quaternary to be mapped across the entire basin. The base-Quaternary has been mapped using the PGS MegaSurvey dataset from wells in the Danish Sector along the initially unconformable horizon and down the delta front into the more conformable basin giving a high degree of confidence in the horizon pick. The revised base-Quaternary surface reaches a depth of 1248 ms TWT with an elongate basin shape which is significantly deeper than the traditionally mapped surface. Using RMS amplitudes and other seismic attributes the revised base-Quaternary has been investigated along the horizon and in time slice to interpret the environments of the earliest Quaternary prior to the onset of glaciation. Combined with analysis of aligned elongate furrows over 10 km long, 100 m wide and 100 m deep suggest a deep marine environment in an almost enclosed basin with persistent strong NW-SE bottom currents in the deepest parts. Pockmarks were formed by the escape of shallow gas on the sides of a small delta in the eastern part of the basin. The progradation of large deltas from both the north and south into the basin make up the majority of the deposition of sediment into the basin. Key Words: base-Quaternary; seismic interpretation; paleoenvironments References: Gatliff, R.W, Richards, P.C, Smith, K, Graham, C.C, McCormac, M, Smith, N.J.P, Long, D, Cameron, T.D.J, Evans, D, Stevenson, A.G, Bulat, J, Ritchie, J.D, (1994) 'United Kingdom offshore regional

  13. Ground-water resources of north-central Connecticut

    Science.gov (United States)

    Cushman, Robert Vittum

    1964-01-01

    The term 'north-central Connecticut' in this report refers to an area of about 640 square miles within the central lowland of the Connecticut River basin north of Middletown. The area is mostly a broad valley floor underlain by unconsolidated deposits of Pleistocene and Recent age which mantle an erosional surface formed on consolidated rocks of pre-Triassic and Triassic age. The mean annual precipitation at Hartford, near the center of the area, is 42.83 inches and is uniformly distributed throughout the year. The average annual streamflow from the area is about 22 inches or about half the precipitation. The consolidated water-bearing formations are crystalline rocks of pre-Triassic age and sedimentary and igneous rocks of the Newark group of Triassic age. The crystalline rocks include the Middletown gneiss, the Maromas granite gneiss, the Glastonbury granite-gneiss of Rice and Gregory (1906), and the Bolton schist which form the basement complex and the Eastern Upland of north-central Connecticut. Enough water for domestic, stock, and small commercial use generally can be obtained from the crystalline rocks. Recoverable ground water occurs in the interconnected joints and fracture zones and is yielded in amounts ranging from 29 to 35 gpm (gallons per minute) to wells ranging in depth from 29 to 550 feet. The sedimentary rocks of Triassic age underlie all the Connecticut River Lowland and are predominantly arkosic sandstone and shale. Water supplies sufficient for domestic, stock, and small commercial use can be obtained from shallow wells penetrating these rocks, and larger supplies sufficient for industries and smaller municipalities can probably be obtained from deeper wells. Reported yields range from ? to 578 gpm; the larger yields are generally obtained from wells between 300 and 600 feet in depth. Yields are larger where the overlying material is sand and gravel or where the rocks are well fractured. The igneous rocks of Triassic age are basalt and have

  14. Revised conceptualization of the North China Basin groundwater flow system: Groundwater age, heat and flow simulations

    Science.gov (United States)

    Cao, Guoliang; Han, Dongmei; Currell, Matthew J.; Zheng, Chunmiao

    2016-09-01

    Groundwater flow in deep sedimentary basins results from complex evolution processes on geological timescales. Groundwater flow systems conceptualized according to topography and/or groundwater table configuration generally assume a near-equilibrium state with the modern landscape. However, the time to reach such a steady state, and more generally the timescales of groundwater flow system evolution are key considerations for large sedimentary basins. This is true in the North China Basin (NCB), which has been studied for many years due to its importance as a groundwater supply. Despite many years of study, there remain contradictions between the generally accepted conceptual model of regional flow, and environmental tracer data. We seek to reconcile these contractions by conducting simulations of groundwater flow, age and heat transport in a three dimensional model, using an alternative conceptual model, based on geological, thermal, isotope and historical data. We infer flow patterns under modern hydraulic conditions using this new model and present the theoretical maximum groundwater ages under such a flow regime. The model results show that in contrast to previously accepted conceptualizations, most groundwater is discharged in the vicinity of the break-in-slope of topography at the boundary between the piedmont and central plain. Groundwater discharge to the ocean is in contrast small, and in general there are low rates of active flow in the eastern parts of the basin below the central and coastal plain. This conceptualization is more compatible with geochemical and geothermal data than the previous model. Simulated maximum groundwater ages of ∼1 Myrs below the central and coastal plain indicate that residual groundwater may be retained in the deep parts of the basin since being recharged during the last glacial period or earlier. The groundwater flow system has therefore probably not reached a new equilibrium state with modern-day hydraulic conditions. The

  15. Laramide structure of the central Sangre de Cristo Mountains and adjacent Raton Basin, southern Colorado

    Science.gov (United States)

    Lindsey, D.A.

    1998-01-01

    Laramide structure of the central Sangre de Cristo Mountains (Culebra Range) is interpreted as a system of west-dipping, basement-involved thrusts and reverse faults. The Culebra thrust is the dominant structure in the central part of the range; it dips 30 -55?? west and brings Precambrian metamorphic base-ment rocks over unmetamorphosed Paleozoic rocks. East of the Culebra thrust, thrusts and reverse faults break the basement and overlying cover rocks into north-trending fault blocks; these boundary faults probably dip 40-60?? westward. The orientation of fault slickensides indicates oblique (northeast) slip on the Culebra thrust and dip-slip (ranging from eastward to northward) movement on adjacent faults. In sedimentary cover rocks, east-vergent anticlines overlie and merge with thrusts and reverse faults; these anticlines are interpreted as fault-propagation folds. Minor east-dipping thrusts and reverse faults (backthrusts) occur in both the hanging walls and footwalls of thrusts. The easternmost faults and folds of the Culebra Range form a continuous structural boundary between the Laramide Sangre de Cristo highland and the Raton Basin. Boundary structures consist of west-dipping frontal thrusts flanked on the basinward side by poorly exposed, east-dipping backthrusts. The backthrusts are interpreted to overlie structural wedges that have been emplaced above blind thrusts in the basin margin. West-dipping frontal thrusts and blind thrusts are interpreted to involve basement, but backthrusts are rooted in basin-margin cover rocks. At shallow structural levels where erosion has not exposed a frontal thrust, the structural boundary of the basin is represented by an anticline or monocline. Based on both regional and local stratigraphic evidence, Laramide deformation in the Culebra Range and accompanying synorogenic sedimentation in the western Raton Basin probably took place from latest Cretaceous through early Eocene time. The earliest evidence of uplift and

  16. Stratigraphy, sedimentology and paleontology of lower Eocene San Jose formation, central San Juan basin, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, S.G.; Smith, L.N. (New Mexico Museum of Natural History, Albuquerque (USA))

    1989-09-01

    The lower Eocene San Jose Formation in the central portion of the San Juan basin (Gobernador-Vigas Canyon area) consists of the Cuba Mesa, Regina, Llaves, and Tapicitos Members. Well log data indicate that, from its 100-m thickness, the Cuba Mesa Member thins toward the basin center and pinches out to the northeast by lat. 36{degree}40'N, long. 107{degree}19'W. The Regina Member has the most extensive outcrops in the central basin, and it decreases in sandstone/mud rock ratio to the north. The Llaves and Tapicitos Members occur only at the highest elevations, are thin due to erosion, and are not mappable as separate units. Well log data and 1,275 m of measured stratigraphic section in the Regina, Llaves, and Tapicitos Members indicate these strata are composed of approximately 35% medium to coarse-grained sandstone and 65% fine-grained sandstone and mud rock. Sedimentology and sediment-dispersal patterns indicate deposition by generally south-flowing streams that had sources to the northwest, northeast, and east. Low-sinuosity, sand-bedded, braided( ) streams shifted laterally across about 1 km-wide channel belts to produce sheet sandstones that are prominent throughout the San Jose Formation. Subtle levees separated channel environments from floodplain and local lacustrine areas. Avulsion relocated channels periodically to areas on the floodplain, resulting in the typically disconnected sheet sandstones within muddy overbank deposits of the Regina Member.

  17. Micro and Macroscale Drivers of Nutrient Concentrations in Urban Streams in South, Central and North America

    Science.gov (United States)

    Loiselle, Steven A.; Gasparini Fernandes Cunha, Davi; Shupe, Scott; Valiente, Elsa; Rocha, Luciana; Heasley, Eleanore; Belmont, Patricia Pérez; Baruch, Avinoam

    2016-01-01

    Global metrics of land cover and land use provide a fundamental basis to examine the spatial variability of human-induced impacts on freshwater ecosystems. However, microscale processes and site specific conditions related to bank vegetation, pollution sources, adjacent land use and water uses can have important influences on ecosystem conditions, in particular in smaller tributary rivers. Compared to larger order rivers, these low-order streams and rivers are more numerous, yet often under-monitored. The present study explored the relationship of nutrient concentrations in 150 streams in 57 hydrological basins in South, Central and North America (Buenos Aires, Curitiba, São Paulo, Rio de Janeiro, Mexico City and Vancouver) with macroscale information available from global datasets and microscale data acquired by trained citizen scientists. Average sub-basin phosphate (P-PO4) concentrations were found to be well correlated with sub-basin attributes on both macro and microscales, while the relationships between sub-basin attributes and nitrate (N-NO3) concentrations were limited. A phosphate threshold for eutrophic conditions (>0.1 mg L-1 P-PO4) was exceeded in basins where microscale point source discharge points (eg. residential, industrial, urban/road) were identified in more than 86% of stream reaches monitored by citizen scientists. The presence of bankside vegetation covaried (rho = –0.53) with lower phosphate concentrations in the ecosystems studied. Macroscale information on nutrient loading allowed for a strong separation between basins with and without eutrophic conditions. Most importantly, the combination of macroscale and microscale information acquired increased our ability to explain sub-basin variability of P-PO4 concentrations. The identification of microscale point sources and bank vegetation conditions by citizen scientists provided important information that local authorities could use to improve their management of lower order river

  18. Slab roll-back and trench retreat as controlling factor for basin subsidence in southern Central America

    Science.gov (United States)

    Brandes, Christian; Winsemann, Jutta

    2015-04-01

    Slab roll-back and trench retreat are important factors for basin subsidence, magma generation and volcanism in arc-trench systems. Based on the sedimentary and tectonic record of the southern Central American island-arc we conclude that repeated phases of slab roll-back and trench retreats occurred the arc-trench system since the Late Cretaceous. These trench retreats were most probably related to the subduction of oceanic plateaus and seamounts and effected both the fore-arc and back-arc evolution. We used numerical basin modelling techniques to analyse the burial history of fore-arc and back-arc basins in Central America and combined the results with field data of the sedimentological evolution of the basin-fills. From the basin models, geohistory curves were extracted for the fore-arc and back-arc basins to derive the subsidence evolution. The Sandino Fore-arc Basin is characterized by low subsidence during the first 40 Myr. Since the Late Cretaceous the basin has a linear moderate subsidence with a phase of accelerated subsidence in the Oligocene. In the North and South Limón Back-arc Basin, subsidence started at approximately the same time as in the Sandino Fore-arc Basin. The North and South Limón Basins show a linear subsidence trend in the Paleocene and Eocene. Evidence for trench retreats is given by pulses of uplift in the outer-arc area, followed by subsidence in both the fore-arc and back-arc basins. The first slab roll-back probably occurred during the Early Paleocene. This is indicated by the collapse of carbonate platforms, and the re-deposition of large carbonate blocks into deep-water turbidites. A new pulse of uplift or decreased subsidence, respectively during the Late Eocene is attributed to subduction of rough crust. A subsequent slab detachment and the establishment of a new subduction zone further westward was described by Walther et al. (2000). Strong uplift affected the entire fore-arc area, which led to the deposition of very coarse

  19. Hydrology of the Estancia Basin, central New Mexico

    Science.gov (United States)

    White, R.R.

    1993-01-01

    The Estancia Basin of central New Mexico is a topographically closed basin that ranges in altitude from 6,000 feet to more than 10,000 feet above sea level. In the center of the basin a valley-fill aquifer of Quaternary age is as much as 400 feet thick. Limestone of the Madera Group of Pennsylvanian and Permian age crops out over most of the southwestern part of the basin. Large-scale ground-water withdrawals for irrigation began about 1950. Between 1950 and 1985, water levels declined 50 to 60 feet in a number of places. From 1985 to the present (1989), however, a small rise in water level has been measured in a number of wells; this rise can be attributed to decreased ground-water withdrawals resulting from a government crop- reduction program and also to several years of heavy winter snowfall. Continuous water-level recorders were placed on three wells from 1986 to 1988. Two of these wells showed short-term water-level changes characteristic of unconfined aquifers, whereas the other showed changes characteristic of confined aquifers. All three wells showed water-level changes caused by barometric-pressure changes. Six series of miscellaneous measurements and two gain-and-loss (seepage) studies were made in streams in the south- western part of the basin. These measurements showed an extreme variability in discharge under different climatic conditions. The specific conductance of water in much of the southwestern part of the basin ranges from 350 to 550 microsiemens per centimeter at 25 degrees Celsius. East of State Highway 41 in the area of the salt lakes, water quality is highly dependent on depth in the aquifer. Specific- conductance values ranging from about 4,000 to 6,000 microsiemens were measured in water samples from wells in the center of the basin during this study, but previous studies have identified water samples having specific-conductance values of as much as 187,000 microsiemens. A comparison of specific- conductance measurements and laboratory

  20. Synthesis of morphotectonics and volcanics of the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Mukherjee, A.D.; Iyer, S.D.

    The Central Indian Ocean Basin (CIOB) is an enigmatic ocean basin in the young and tectonically complex Indian Ocean. Major tectonic and volcanic forms identified are fracture zones, abyssal hills, seamounts and ridges and a unique zone...

  1. Well installation, single-well testing, and particle-size analysis for selected sites in and near the Lost Creek Designated Ground Water Basin, north-central Colorado, 2003-2004

    Science.gov (United States)

    Beck, Jennifer A.; Paschke, Suzanne S.; Arnold, L. Rick

    2011-01-01

    This report describes results from a groundwater data-collection program completed in 2003-2004 by the U.S. Geological Survey in support of the South Platte Decision Support System and in cooperation with the Colorado Water Conservation Board. Two monitoring wells were installed adjacent to existing water-table monitoring wells. These wells were installed as well pairs with existing wells to characterize the hydraulic properties of the alluvial aquifer and shallow Denver Formation sandstone aquifer in and near the Lost Creek Designated Ground Water Basin. Single-well tests were performed in the 2 newly installed wells and 12 selected existing monitoring wells. Sediment particle size was analyzed for samples collected from the screened interval depths of each of the 14 wells. Hydraulic-conductivity and transmissivity values were calculated after the completion of single-well tests on each of the selected wells. Recovering water-level data from the single-well tests were analyzed using the Bouwer and Rice method because test data most closely resembled those obtained from traditional slug tests. Results from the single-well test analyses for the alluvial aquifer indicate a median hydraulic-conductivity value of 3.8 x 10-5 feet per second and geometric mean hydraulic-conductivity value of 3.4 x 10-5 feet per second. Median and geometric mean transmissivity values in the alluvial aquifer were 8.6 x 10-4 feet squared per second and 4.9 x 10-4 feet squared per second, respectively. Single-well test results for the shallow Denver Formation sandstone aquifer indicate a median hydraulic-conductivity value of 5.4 x 10-6 feet per second and geometric mean value of 4.9 x 10-6 feet per second. Median and geometric mean transmissivity values for the shallow Denver Formation sandstone aquifer were 4.0 x 10-5 feet squared per second and 5.9 x 10-5 feet squared per second, respectively. Hydraulic-conductivity values for the alluvial aquifer in and near the Lost Creek Designated

  2. Structure of the Anayet Permian basin (Axial Zone, Central Pyrenees)

    Science.gov (United States)

    Rodriguez, L.; Cuevas, J.; Tubía, J. M.

    2012-04-01

    The Anayet Permian basin was generated by strike-slip tectonics that opened subsident basins with pull-apart geometries in the western Spanish Axial Zone (between the Aragon and Tena valleys). A continental succession of Permian age, that represents the first post-variscan deposits in the area, fills the basin and covers discordantly Devonian to Carboniferous limestones, sandstones and slates. Permian deposits have been classically divided in four main detrital groups, with three basic volcanic episodes interbedded (Gisbert, 1984, Bixel, 1987): the Grey Unit (50-120 m, Estefanian to Kungurian) with slates, conglomerates, tobaceous slates, coal and pyroclastic deposits, the Transition Unit (50 m maximum) showing grey and red sandstones and lutites with oolitic limestones intercalated, the Lower Red Unit (250 m) composed of cross-bedded red sandstones and andesitic volcanic rocks at the top, and finally the Upper Red Unit (400 m minimum, top eroded) formed by three fining up megasequences of carbonates, red sandstones and lutites with lacustrine carbonates intercalated and alkali basalts at the top. Increasingly older rocks are found towards the western part of the basin, where its depocenter is located. South-vergent angular folds deform the Permian sedimentary succession. Fold axes are N115 °E-trending, almost horizontal and are characterized by a remarkably constant orientation. Folds exhibit a long limb dipping slightly to the north and a short vertical limb, occasionally reversed. In the Anayet basin four main folds, with a wavelength of 400 m, can be distinguished, two anticlines and two synclines, with minor folds associated. Related to the angular folds an axial plane foliation, E-trending and dipping 40 to 60° to the north, is developed in the lutites. The more competent rocks, conglomerates and breccias, only locally show a spaced fracture cleavage. No main thrusts have been detected in Permian rocks. However, minor scale decollements, usually low angle

  3. Landslide Deposit Boundaries for the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This layer is an inventory of existing landslides deposits in the Little North Santiam River Basin, Oregon (2009). Each landslide deposit shown on this map has been...

  4. Timber Harvest Change in the Little North Santiam River Basin, Oregon, 1995 to 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Using available aerial photos from approximately a 15-year period, changes in timber harvest were mapped in the Little North Santiam River Basin, Oregon. Timber...

  5. Location of Photographs Showing Landslide Features in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data points represent locations of photographs taken of landslides in the Little North Santiam River Basin, Oregon. Photos were taken in spring of 2010 during field...

  6. Head Scarp Boundary for the Landslides in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Polygons represent head scarps and flank scarps associated with landslide deposits in the Little North Santiam River Basin, Oregon. This work was completed as part...

  7. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2006-05-26

    The principal research effort for Phase 1 (Concept Development) of the project has been data compilation; determination of the tectonic, depositional, burial, and thermal maturation histories of the North Louisiana Salt Basin; basin modeling (geohistory, thermal maturation, hydrocarbon expulsion); petroleum system identification; comparative basin evaluation; and resource assessment. Existing information on the North Louisiana Salt Basin has been evaluated, an electronic database has been developed, and regional cross sections have been prepared. Structure, isopach and formation lithology maps have been constructed, and burial history, thermal maturation history, and hydrocarbon expulsion profiles have been prepared. Seismic data, cross sections, subsurface maps and burial history, thermal maturation history, and hydrocarbon expulsion profiles have been used in evaluating the tectonic, depositional, burial and thermal maturation histories of the basin. Oil and gas reservoirs have been found to be associated with salt-supported anticlinal and domal features (salt pillows, turtle structures and piercement domes); with normal faulting associated with the northern basin margin and listric down-to-the-basin faults (state-line fault complex) and faulted salt features; and with combination structural and stratigraphic features (Sabine and Monroe Uplifts) and monoclinal features with lithologic variations. Petroleum reservoirs include Upper Jurassic and Cretaceous fluvial-deltaic sandstone facies; shoreline, marine bar and shallow shelf sandstone facies; and carbonate shoal, shelf and reef facies. Cretaceous unconformities significantly contribute to the hydrocarbon trapping mechanism capacity in the North Louisiana Salt Basin. The chief petroleum source rock in this basin is Upper Jurassic Smackover lime mudstone beds. The generation of hydrocarbons from Smackover lime mudstone was initiated during the Early Cretaceous and continued into the Tertiary. Hydrocarbon

  8. Paleoseismological investigations and Geomorphology on the Gaenserndorf Terrace in the central Vienna Basin (Austria)

    Science.gov (United States)

    Weissl, Michael; Hintersberger, Esther; Lomax, Johanna; Decker, Kurt

    2016-04-01

    In the central Vienna Basin normal faults define the eastern and western margins of Pleistocene Danube terraces north of Vienna. The terrace body is built up of coarse sandy gravel and sand. Locally the terrace surface is covered with eolian and alluvial sediments of the last glacial revealing OSL/IRSL ages of about 15-16 ka. High resolution digital terrain models (LIDAR) show relicts of a periglacial landscape in the northern part of the Middle Pleistocene (MIS 8) terrace. Large elongated depressions in the northern parts of the terrace are interpreted as the basins of former thermokarst lakes due to analogies in recent periglacial zones. Draining valleys corrugate the fault scarps indicating advanced subsidence of the Aderklaa and Obersiebenbrunn Quaternary basins before the last Glacial. Obviously the periglacial morphology is only preserved in the elevated parts of the terrace which is located in the footwall of the bounding normal faults. In the hanging wall Quaternary basins are filled with up to 40 m thick Pleistocene and Holocene growth strata. During the last decade three faults were investigated by trenching. In contrast to the earlier trench sites on the Markgrafneusiedl Fault and the Vienna Basin Transform Fault it was not possible to provide clear evidence for offset on the Aderklaa-Bockfliess fault because cryoturbation deformed the covering fluvial sediments together with the underlying Gaenserndorf terrace gravels. However it was possible to localize this fault precisely applying an electrical resistivity tomography. The resulting ERT-section shows an offset of the 200-300 ky old terrace and the underlying Miocene sediments of about 9-10 meters suggesting a vertical slip rate of 0.03 - 0.05 mm/a.

  9. The isolation of the Pannonian basin (Central Paratethys): New constraints from magnetostratigraphy and biostratigraphy

    NARCIS (Netherlands)

    Borgh, M.M. ter; Vasiliev, I.; Stoica, M.; Knežević, S.; Matenco, L.C.; Krijgsman, W.; Rundić, L.; Cloetingh, S.

    2013-01-01

    In this paper we establish when and how the Pannonian basin and associated Central Paratethys basins were isolated from the remainder of the Paratethys, a system of back-arc basins and inland seas that once extended over a large part of Europe. The isolation, which occurred at the beginning of the L

  10. A Darriwilian (Middle Ordovician bivalve-dominated molluscan fauna from the Stairway Sandstone, Amadeus Basin, central Australia

    Directory of Open Access Journals (Sweden)

    Kristian G. Jakobsen

    2016-12-01

    Full Text Available A bivalve-dominated molluscan fauna is described from the Darriwilian (Middle Ordovician Stairway Sandstone, Amadeus Basin, central Australia. The fauna comprises 16 species of bivalves and rostroconchs plus six gastropod species which are treated under open nomenclature. Two new bivalves, Sthenodonta paenesymmetrica sp. nov. and Modiolopsis pojetai sp. nov., are described. The relatively low-diverse molluscan fauna constitutes around 62% of the total benthic macrofauna. Approximately 75% of the molluscs comprise bivalves, especially nuculoids, which were biogeographically restricted to low latitudes during the Ordovician. The molluscan assemblage displays a very high degree of endemism at species level, though the bivalve Sthenodonta eastii also occurs in the Georgina Basin farther to the northeast. This indicates a possible marine connective seaway between the Georgina and Amadeus basins during the Darriwilian. Nuculites, Cyrtodonta, and Modiolopsis are cosmopolitan and previously reported from North China, Avalonia, and Southern Gondwana.

  11. Moisture transport from the Atlantic to the Pacific basin and its response to North Atlantic cooling and global warming

    Energy Technology Data Exchange (ETDEWEB)

    Richter, Ingo [University of Hawaii at Manoa, International Pacific Research Center, Honolulu, HI (United States); Xie, Shang-Ping [University of Hawaii at Manoa, Department of Meteorology, Honolulu, HI (United States)

    2010-08-15

    Atmospheric moisture transport from the Atlantic to the Pacific basin plays an important role in regulating North Atlantic salinity and thus the strength of the thermohaline circulation. Potential changes in the strength of this moisture transport are investigated for two different climate-change scenarios: North Atlantic cooling representative of Heinrich events, and increased greenhouse gas (GHG) forcing. The effect of North Atlantic cooling is studied using a coupled regional model with comparatively high resolution that successfully simulates Central American gap winds and other important aspects of the region. Cooler North Atlantic sea surface temperature (SST) in this model leads to a regional decrease of atmospheric moisture but also to an increase in wind speed across Central America via an anomalous pressure gradient. The latter effect dominates, resulting in a 0.13 Sv (1 Sv = 10{sup 6} m{sup 3} s{sup -1}) increase in overall moisture transport to the Pacific basin. In fresh water forcing simulations with four different general circulation models, the wind speed effect is also present but not strong enough to completely offset the effect of moisture decrease except in one model. The influence of GHG forcing is studied using simulations from the Intergovernmental Panel on Climate Change archive. In these simulations atmospheric moisture increases globally, resulting in an increase of moisture transport by 0.25 Sv from the Atlantic to Pacific. Thus, in both scenarios, moisture transport changes act to stabilize the thermohaline circulation. The notion that the Andes effectively block moisture transport from the Atlantic to the Pacific basin is not supported by the simulations and atmospheric reanalyses examined here. This indicates that such a blocking effect does not exist or else that higher resolution is needed to adequately represent the steep orography of the Andes. (orig.)

  12. BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard; Ronald K. Zimmerman

    2005-05-10

    The principal research effort for Year 2 of the project has been data compilation and the determination of the burial and thermal maturation histories of the North Louisiana Salt Basin and basin modeling and petroleum system identification. In the first nine (9) months of Year 2, the research focus was on the determination of the burial and thermal maturation histories, and during the remainder of the year the emphasis has basin modeling and petroleum system identification. Existing information on the North Louisiana Salt Basin has been evaluated, an electronic database has been developed, regional cross sections have been prepared, structure and isopach maps have been constructed, and burial history, thermal maturation history and hydrocarbon expulsion profiles have been prepared. Seismic data, cross sections, subsurface maps and related profiles have been used in evaluating the tectonic, depositional, burial and thermal maturation histories of the basin. Oil and gas reservoirs have been found to be associated with salt-supported anticlinal and domal features (salt pillows, turtle structures and piercement domes); with normal faulting associated with the northern basin margin and listric down-to-the-basin faults (state-line fault complex) and faulted salt features; and with combination structural and stratigraphic features (Sabine and Monroe Uplifts) and monoclinal features with lithologic variations. Petroleum reservoirs are mainly Upper Jurassic and Lower Cretaceous fluvial-deltaic sandstone facies and Lower Cretaceous and Upper Cretaceous shoreline, marine bar and shallow shelf sandstone facies. Cretaceous unconformities significantly contribute to the hydrocarbon trapping mechanism capacity in the North Louisiana Salt Basin. The chief petroleum source rock in this basin is Upper Jurassic Smackover lime mudstone beds. The generation of hydrocarbons from Smackover lime mudstone was initiated during the Early Cretaceous and continued into the Tertiary

  13. Geologic Assessment of Undiscovered Oil and Gas Resources of the North Cuba Basin, Cuba

    Science.gov (United States)

    Schenk, Christopher J.

    2010-01-01

    Petroleum generation in the North Cuba Basin is primarily the result of thrust loading of Jurassic and Cretaceous source rocks during formation of the North Cuba fold and thrust belt in the Late Cretaceous to Paleogene. The fold and thrust belt formed as Cuban arc-forearc rocks along the leading edge of the Caribbean plate translated northward during the opening of the Yucatan Basin and collided with the passive margin of southern North America in the Paleogene. Petroleum fluids generated during thrust loading migrated vertically into complex structures in the fold and thrust belt, into structures in the foreland basin, and possibly into carbonate reservoirs along the margins of the Yucatan and Bahama carbonate platforms. The U.S. Geological Survey (USGS) defined a Jurassic-Cretaceous Composite Total Petroleum System (TPS) and three assessment units (AU)-North Cuba Fold and Thrust Belt AU, North Cuba Foreland Basin AU, and the North Cuba Platform Margin Carbonate AU-within this TPS based mainly on structure and reservoir type (fig. 1). There is considerable geologic uncertainty as to the extent of petroleum migration that might have occurred within this TPS to form potential petroleum accumulations. Taking this geologic uncertainty into account, especially in the offshore area, the mean volumes of undiscovered resources in the composite TPS of the North Cuba Basin are estimated at (1) 4.6 billion barrels of oil (BBO), with means ranging from an F95 probability of 1 BBO to an F5 probability of 9 BBO; and (2) 8.6 trillion cubic feet of of gas (TCFG), of which 8.6 TCFG is associated with oil fields, and about 1.2 TCFG is in nonassociated gas fields in the North Cuba Foreland Basin AU.

  14. Tectonic inversion in the Wandel Sea Basin: A new structural model of Kilen (eastern North Greenland)

    Science.gov (United States)

    Svennevig, Kristian; Guarnieri, Pierpaolo; Stemmerik, Lars

    2016-12-01

    The seminunatak Kilen in eastern North Greenland, with its complexly deformed Carboniferous-Cretaceous strata, is a key area to understand the tectonic history of the transform plate boundary between eastern North Greenland and Svalbard. Detailed 3-D geological mapping from oblique photogrammetry along with limited ground fieldwork and interpretation of previously published data forms the basis for a new structural model of Kilen. Previous structural models interpreted rhombic-shaped fault patterns as the evidence for strike-slip tectonics. These structures are here interpreted to be the result of a post-Coniacian NE-SW extension with NW-SE trending normal faults followed by later, N-S compression of presumable Paleocene-Eocene age, folding the faults passively and suggesting the presence of a basal detachment. Furthermore, two thrust sheets have been distinguished on Kilen: a lower Kilen Thrust Sheet and an upper Hondal Elv Thrust Sheet separated by a subhorizontal fault: the Central Detachment. The style of deformation and the structures described are interpreted as the result of Paleocene-Eocene N-S directed compression resulting in basin inversion with strike-slip faults only having minor status. This indicates that the Greenland margin as exposed on Kilen and the conjugate Svalbard margin in the West Spitsbergen fold-and-thrust belt are more similar than previously anticipated.

  15. Systematic status of wild Canis in North-central Texas

    Science.gov (United States)

    Mech, L. David; Nowak, Ronald M.

    2010-01-01

    Skulls of wild Canis collected 2003–2004 in north-central Texas are morphometrically similar to a series taken there and in nearby areas in 1964–1971, which was considered to represent a population of Coyotes (C. latrans) modified through introgression from Red Wolves (C. rufus). A few of the new specimens closely resemble small examples of Red Wolves. Such affinity is supported by authoritative examination of living and videotaped animals. The persistence of influence of Red Wolves, long after presumed extirpation through hybridization and human persecution, may be relevant to wolf conservation.

  16. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2006-02-28

    The principal research effort for Year 3 of the project is basin modeling and petroleum system identification, comparative basin evaluation and resource assessment. In the first six (6) months of Year 3, the research focus is on basin modeling and petroleum system identification and the remainder of the year the emphasis is on the comparative basin evaluation and resource assessment. No major problems have been encountered to date, and the project is on schedule. The principal objectives of the project are to develop through basin analysis and modeling the concept that petroleum systems acting in a basin can be identified through basin modeling and to demonstrate that the information and analysis resulting from characterizing and modeling of these petroleum systems in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin can be used in providing a more reliable and advanced approach for targeting stratigraphic traps and specific reservoir facies within a geologic system and in providing a refined assessment of undiscovered and underdeveloped reservoirs and associated oil and gas resources.

  17. The Precambrian Structure of the Estancia Basin, Central New Mexico: New Seismic Images of the Mazatzal Province

    Science.gov (United States)

    Elebiju, O. O.; Miller, K. C.; Andronicos, C. L.

    2004-12-01

    The Estancia Basin, located between the Manzano Mountains and Pedernal Hills, in central New Mexico, provides an excellent location for studying the effects of Proterozoic structural grain on subsequent Phanerozoic tectonic events. The Estancia Basin lies within the Proterozoic Mazatzal province. In recent years, the National Science Foundation Continental Dynamics Program within the Rocky Mountains Project, (CD-ROM) group has been examining the boundary between the two broad northeast-trending tectonically-mixed Paleoproterozoic terranes in New Mexico: the Yavapai province to the north and the Mazatzal province to the south. Reflection data collected as part of the CD-ROM effort image a portion of the Mazatzal province at a location 100 km east of the Estancia Basin. In an effort to contribute to a deeper understanding of the CD-ROM seismic image and regional Precambrian geology, we are analyzing ten seismic reflection profiles, well-logs, magnetic and gravity data from the Estancia basin area. The seismic data show numerous dipping reflections within the Precambrian basement that may represent prominent Precambrian ductile shear zones similar to those exposed in the adjacent Manzano Mountains and Pedernal Hills. An earlier study that focused on the Paleozoic evolution of the Estancia Basin, by Barrow and Keller (1994) also noted these same reflectors and that a prominent gravity low observed in the vicinity of the basin could not be fully explained by the Paleozoic geology. We present a new interpretation of these data.

  18. Chapter 44: Geology and petroleum potential of the Lincoln Sea Basin, offshore North Greenland

    Science.gov (United States)

    Sorensen, K.; Gautier, D.; Pitman, J.; Ruth, Jackson H.; Dahl-Jensen, T.

    2011-01-01

    A seismic refraction line crossing the Lincoln Sea was acquired in 2006. It proves the existence of a deep sedimentary basin underlying the Lincoln Sea. This basin appears to be comparable in width and depth to the Sverdrup Basin of the Canadian Arctic Islands. The stratigraphy of the Lincoln Sea Basin is modelled in analogy to the Sverdrup Basin and the Central Spitsbergen Basin, two basins between which the Lincoln Sea intervened before the onset of seafloor spreading in the Eurasian Basin. The refraction data indicates that the Lincoln Sea Basin is capped by a kilometre-thick, low-velocity layer, which is taken to indicate an uplift history similar to, or even more favourable than, the fairway part of the Sverdrup Basin. Tectonic activity in the Palaeogene is likely to constitute the major basin scale risk. We conclude that the Lincoln Sea Basin is likely to be petroliferous and contains risked resources on the order of 1 ?? 109 barrels of oil, to which comes an equivalent amount of (associated and nonassociated) gas. ?? 2011 The Geological Society of London.

  19. A seismic gap at the central Vienna Basin Transfer Fault (Vienna Basin, Austria)?

    Science.gov (United States)

    Hintersberger, Esther; Decker, Kurt

    2014-05-01

    The Vienna Basin Transfer Fault (VBTF), a NNE-SSW striking left-lateral strike-slip fault, is the dominant active tectonic structure within the Vienna Basin (Austria), a pull-apart basin between the Alps and the Carpathians. Moderate seismicity (Imax/Mmax = 8-9/5.7) is focused along the southern and northern tips of the VBTF, whereas there are almost no earthquake records during the last ~ 500 years for the central part of the basin, the so-called Lassee segment close to the cities of Vienna (Austria) and Bratislava (Slovakia). Therefore, seismic slip rates calculated from cumulative scalar seismic moments for different segments along the fault are quite heterogeneous, varying from 0.5-1.1 mm/a at the southern and northern tips to the apparently seismically locked Lassee segment. Geological and morphological data, however, document horizontal Quaternary slip rates of 1-2 mm/a for the VBTF. In order to address the ambiguity between long-term and short-term slip rates at the Lassee segment, we concentrated on the tectonically controlled western margin of a Pleistocene Danube terrace (200-300 ka), where the VBTF has produced a ~ 25 m high scarp. Research presented here include interpretation of a LIDAR-based DEM, and paleoseismological trenching. Results from 3D trenching show several faults within the trenches dissecting the Pleistocene Danube gravel terrace. Based on displaced layers, tension cracks and colluvial wedges, at least 3 major earthquakes since ~ 20 ka can be determined, with the most recent one occurring after ~ 2500 years BP and reaching almost the present-day surface. In addition, channels from a small stream crossing the fault almost perpendicular are horizontally offset by ~ 2 m. Considering this offset being the result of the last earthquake, slip along the VBTF seem to be accomodated by earthquakes with estimated magnitudes of ~ 7 and return periods of several thousend years. Therefore, the apparently seismically locked Lassee segment might

  20. Regional geothermal exploration in north central New Mexico. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Icerman, L. (ed.)

    1984-02-01

    A broad-based geothermal resource reconnaissance study covering Bernalillo, Los Alamos, Rio Arriba, San Miguel, Sandoval, Santa Fe, Taos, Torrance, and Valencia counties in north central New Mexico was conducted from June 15, 1981, through September 30, 1983. Specific activities included the compilation of actual temperature, bottom-hole temperature gradient, and geotemperature data; tabulation of water chemistry data; field collection of temperature-depth data from existing wells; and drilling of temperature gradient holes in the Ojo Caliente, San Ysidro, Rio Puerco, and Polvadera areas. The data collected were used to perform: (1) a regional analysis of the geothermal energy potential of north central New Mexico; (2) two site-specific studies of the potential relationship between groundwater constrictions and geothermal resources; (3) an evaluation of the geothermal energy potential at Santa Ana Pueblo; (4) a general analysis of the geothermal energy resources of the Rio Grande Rift, including specific data on the Valles Caldera; and (5) an evaluation of the use of geothermometers on New Mexico groundwaters. Separate abstracts were prepared for individual chapters.

  1. Proceedings of the North Aleutian Basin information status and research planning meeting.

    Energy Technology Data Exchange (ETDEWEB)

    LaGory, K. E.; Krummel, J. R.; Hayse, J. W.; Hlohowskyj, I.; Stull, E. A.; Gorenflo, L.; Environmental Science Division

    2007-10-26

    The North Aleutian Basin Planning Area of the Minerals Management Service (MMS) is a large geographic area with significant ecological and natural resources. The Basin includes most of the southeastern part of the Bering Sea continental shelf including all of Bristol Bay. The area supports important habitat for a wide variety of species and globally significant habitat for birds and marine mammals including federally listed species. Villages and communities of the Alaska Peninsula and other areas bordering or near the Basin rely on its natural resources (especially commercial and subsistence fishing) for much of their sustenance and livelihood. The offshore area of the North Aleutian Basin is considered to have important hydrocarbon reserves, especially natural gas. In 2006, the MMS released a draft proposed program, Outer Continental Shelf Oil and Gas Leasing Program, 2007-2012 and an accompanying draft programmatic environmental impact statement (EIS). The draft proposed program identified two lease sales proposed in the North Aleutian Basin in 2010 and 2012, subject to restrictions. The area proposed for leasing in the Basin was restricted to the Sale 92 Area in the southwestern portion. Additional EISs will be needed to evaluate the potential effects of specific lease actions, exploration activities, and development and production plans in the Basin. A full range of updated multidisciplinary scientific information will be needed to address oceanography, fate and effects of oil spills, marine ecosystems, fish, fisheries, birds, marine mammals, socioeconomics, and subsistence in the Basin. Scientific staff at Argonne National Laboratory (Argonne) were contracted to assist the MMS Alaska Outer Continental Shelf (OCS) Region in identifying and prioritizing information needs related to the North Aleutian Basin and potential future oil and gas leasing and development activities. The overall approach focused on three related but separate tasks: (1) identification and

  2. Anatomy of a rift system: Triassic-Jurassic basins of eastern North America

    Energy Technology Data Exchange (ETDEWEB)

    Schlische, R.W. (Rutgers Univ., New Brunswick, NJ (United States)); Olsen, P.E. (Columbia Univ., Palisades, NY (United States))

    1991-03-01

    Basins containing the early Mesozoic Newark Supergroup formed during the incipient rifting of Pangaea. The basins are characterized by the following: (1) The border fault systems (BFS) represent reactivated older faults. (2) A regionally persistent northwest-southeast to west-northeast-east-southeast extension direction reactivated northeast- to north-striking structures as predominantly normal dip-slip faults. (3) The half-grabens are lozenge-shaped basins in which subsidence-fault slip was greatest at or near the center of the BFS and decreased to zero toward either end. (4) Transverse folds in the hanging walls immediately adjacent to the BFS formed as a result of higher-frequency variations in subsidence. (5) Subsidence also decreased in a direction perpendicular to the BFS. (6) Intrabasinal faults are overwhelmingly synthetic and predominantly post-depositional. (7) Younger strata progressively onlap prerift rocks of the hanging wall block; this indicates that the basins grew both in width and length as they filled. (8) In all basins initial sedimentation was fluvial, reflecting an oversupply of sediment with respect to basin capacity. (9) Sediments were derived largely from the hanging wall block, which sloped toward the basin, and from streams that entered the basin axially; a direct footwall source was minor, owing to footwall uplift. (10) In strike-slip-dominated basins, subsidence was considerably less than in dip-slip basins, and mosaics of strike- and dip-slip faults are common.

  3. Surface Area Variability of a North-Central Tanzanian Crater Lake

    Directory of Open Access Journals (Sweden)

    Lindsey Higgins

    2016-06-01

    Full Text Available A history of modern (1973–2015 surface area variability for Lake Basotu in north-central Tanzania has been reconstructed using archived Landsat images from the dry season between June and October. This record was compared to local weather data as well as larger scale weather patterns. The lake has been in a state of decline interrupted by major flood events since the beginning of the satellite record. From 1973 to 1997, the lake area was between 0.97 km2 and 4.28 km2. Lake extent abruptly increased to 13.86 km2 in 1998, when a co-occurrence of El Niño and a positive Indian Ocean Dipole led to extensive flooding. It is hypothesized that local agricultural practices leading to soil erosion and subsequent basin sedimentation have most likely increased the sensitivity of Lake Basotu to climatic fluctuations.

  4. Statistical Aspects of the North Atlantic Basin Tropical Cyclones: Trends, Natural Variability, and Global Warming

    Science.gov (United States)

    Wilson, Robert M.

    2007-01-01

    Statistical aspects of the North Atlantic basin tropical cyclones for the interval 1945- 2005 are examined, including the variation of the yearly frequency of occurrence for various subgroups of storms (all tropical cyclones, hurricanes, major hurricanes, U.S. landfalling hurricanes, and category 4/5 hurricanes); the yearly variation of the mean latitude and longitude (genesis location) of all tropical cyclones and hurricanes; and the yearly variation of the mean peak wind speeds, lowest pressures, and durations for all tropical cyclones, hurricanes, and major hurricanes. Also examined is the relationship between inferred trends found in the North Atlantic basin tropical cyclonic activity and natural variability and global warming, the latter described using surface air temperatures from the Armagh Observatory Armagh, Northern Ireland. Lastly, a simple statistical technique is employed to ascertain the expected level of North Atlantic basin tropical cyclonic activity for the upcoming 2007 season.

  5. Modes of sedimentary basin formation in the north-eastern Black Sea

    Science.gov (United States)

    Stephenson, Randell; Starostenko, Vitaly; Sydorenko, Grygoriy; Yegorova, Tamara

    2016-04-01

    The Greater Caucasus and Black Sea sedimentary basins developed in a Mesozoic back-arc setting, the former older than the latter (Jurassic v. Cretaceous). Compressional shortening of the former and accompanying ongoing development of marginal basin depocentres in the north-eastern Black Sea - which is closely tied to the formation of the Crimea-Greater Caucasus orogen - is a Cenozoic phenomenon, starting in the Eocene and proceeding until the present day. Recently, the sedimentary basin/crust/lithosphere geometry of the study area has been characterised across a range of scales using regional seismic reflection profiling, long-offset refraction/wide-angle reflection profiling and local earthquake tomography. These provide a new integrated image of the present-day crustal structure and sedimentary basin architecture of the northern margin of the eastern Black Sea, north across the Azov Sea and provide evidence of the deeper expression of sedimentary basins and the processes controlling the geometry of their inversion during the Cenozoic. It is inferred that the Greater Caucasus paleo-Basin, lying stratigraphically below the Black Sea and younger sedimentary successions, extends further to the west than previously known. This basin has significant thickness in the area between the Azov and Black seas and probably forms the deeper core of the Crimea-Caucasus inversion zone. The Crimea-Greater Caucasus orogenic belt is the expression of "basin inversion" of the Jurassic Greater Caucasus paleo-Basin, the degree of inversion of which varies along strike. The Greater Caucasus foredeep basins - Indolo-Kuban and Sorokin-Tuapse troughs -represent syn-inversional marginal troughs to the main inversion zone. The Shatsky Ridge - the northern flank of the main East Black Sea Basin - may also be mainly a syn-inversional structure, underlain by a blind thrust zone expressed as a northward dipping zone of seismicity on the northern margin of the eastern Black Sea.

  6. Magnetic anomalies across Bastar craton and Pranhita–Godavari basin in south of central India

    Indian Academy of Sciences (India)

    I V Radhakrishna Murthy; S Bangaru Babu

    2009-02-01

    Aeromagnetic anomalies over Bastar craton and Pranhita –Godavari (P –G)basin in the south of central India could be attributed to NW –SE striking mafic intrusives in both the areas at variable depths.Such intrusions can be explained considering the collision of the Bastar and Dharwar cratons by the end of the Archaean and the development of tensile regimes that followed in the Paleoproterozoic,facilitating intrusions of mafic dykes into the continental crust.The P –G basin area,being a zone of crustal weakness along the contact of the Bastar and Dharwar cratons, also experienced extensional tectonics.The inferred remanent magnetization of these dykes dips upwards and it is such that the dykes are oriented towards the east of the magnetic north at the time of their formation compared to their present NW –SE strike.Assuming that there was no imprint of magnetization of a later date,it is concluded that the Indian plate was located in the southern hemisphere,either independently or as part of a supercontinent,for some span of time during Paleoproterozoic and was involved in complex path of movement and rotation subsequently. The paper presents a case study of the utility of aeromagnetic anomalies in qualitatively deducing the palaeopositions of the landmasses from the interpreted remanent magnetism of buried intrusive bodies.

  7. Tectonic Evolution of the North Depression of the South Yellow Sea Basin Since Late Cretaceous

    Institute of Scientific and Technical Information of China (English)

    LI Nan; LI Weiran; LONG Haiyan

    2016-01-01

    On the basis of subsidence history analysis and balanced cross-section analysis, the vertical uplift/subsidence history and horizontal extension/compression history of the north depression of the south Yellow Sea basin are quantitatively studied. The results show that the tectonic evolution of the north depression of the south Yellow Sea basin since late Cretaceous can be divided into a rifting phase (late Cretaceous to Paleogene) and a post-rifting phase (Neogene to Quaternary). The rifting phase can be further subdivided into an initial rifting stage (late Cretaceous), an intensive rifting stage (Paleocene), a rifting termination stage (Eocene), and an inversion-uplifting stage (Oligocene). Together, this division shows the characteristics of an episodic-evolved intracontinental rift-depression basin. The deformation of the north depression of the south Yellow Sea basin since late Cretaceous was mainly fault-related. The horizontal extension and tectonic subsidence were controlled by the activity of faults. The differential evolution of faults also caused variations in local uplift/subsidence movements and the regional heterogeneity in extension. The late Cretaceous initial rifting of the north depression of the south Yellow Sea basin is related to the Pacific-Eurasia convergence. From the Paleocene intensive rifting stage to present, the Pacific-Eurasia convergence and India-Eurasia convergence have played important roles in the evolution of this region.

  8. Tectonic evolution of the north depression of the south Yellow Sea basin since late Cretaceous

    Science.gov (United States)

    Li, Nan; Li, Weiran; Long, Haiyan

    2016-12-01

    On the basis of subsidence history analysis and balanced cross-section analysis, the vertical uplift/subsidence history and horizontal extension/compression history of the north depression of the south Yellow Sea basin are quantitatively studied. The results show that the tectonic evolution of the north depression of the south Yellow Sea basin since late Cretaceous can be divided into a rifting phase (late Cretaceous to Paleogene) and a post-rifting phase (Neogene to Quaternary). The rifting phase can be further subdivided into an initial rifting stage (late Cretaceous), an intensive rifting stage (Paleocene), a rifting termination stage (Eocene), and an inversion-uplifting stage (Oligocene). Together, this division shows the characteristics of an episodic-evolved intracontinental rift-depression basin. The deformation of the north depression of the south Yellow Sea basin since late Cretaceous was mainly fault-related. The horizontal extension and tectonic subsidence were controlled by the activity of faults. The differential evolution of faults also caused variations in local uplift/subsidence movements and the regional heterogeneity in extension. The late Cretaceous initial rifting of the north depression of the south Yellow Sea basin is related to the Pacific-Eurasia convergence. From the Paleocene intensive rifting stage to present, the Pacific-Eurasia convergence and India-Eurasia convergence have played important roles in the evolution of this region.

  9. Evaporation from groundwater discharge playas, Estancia Basin, central New Mexico

    Science.gov (United States)

    Menking, Kirsten M.; Anderson, Roger Y.; Brunsell, Nathaniel A.; Allen, Bruce D.; Ellwein, Amy L.; Loveland, Thomas A.; Hostetler, Steven W.

    2000-07-01

    Bowen ratio meteorological stations have been deployed to measure rates of evaporation from groundwater discharge playas and from an adjacent vegetated bench in the Estancia Basin, in central New Mexico. The playas are remnants of late Pleistocene pluvial Lake Estancia and are discharge areas for groundwater originating as precipitation in the adjacent Manzano Mts. They also accumulate water during local precipitation events. Evaporation is calculated from measured values of net radiation, soil heat flux, atmospheric temperature, and relative humidity. Evaporation rates are strongly dependent on the presence or absence of standing water in the playas, with rates increasing more than 600% after individual rainstorms. Evaporation at site E-12, in the southeastern part of the playa complex, measured 74 cm over a yearlong period from mid-1997 through mid-1998. This value compares favorably to earlier estimates from northern Estancia playas, but is nearly three times greater than evaporation at a similar playa in western Utah. Differences in geographical position, salt crust composition, and physical properties may explain some of the difference in evaporation rates in these two geographic regions.

  10. Diagnostic Analysis on a Regional Rainstorm Weather in North-central Henan Province

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The research aimed to analyze a regional rainstorm weather process in north-central Henan Province. [Method] Based on the conventional meteorological observation data and the rainfall data of Henan Meteorological Station, the diagnostic analysis of atmospheric thermodynamics and dynamics on a rainstorm weather process in north-central Henan Province on July 19, 2010 was carried out. The characteristics of physical quantity field and the evolution of weather situation in north-central Henan Provi...

  11. Literature and information related to the natural resources of the North Aleutian Basin of Alaska.

    Energy Technology Data Exchange (ETDEWEB)

    Stull, E.A.; Hlohowskyj, I.; LaGory, K. E.; Environmental Science Division

    2008-01-31

    The North Aleutian Basin Planning Area of the Minerals Management Service (MMS) is a large geographic area with significant natural resources. The Basin includes most of the southeastern part of the Bering Sea Outer Continental Shelf, including all of Bristol Bay. The area supports important habitat for a wide variety of species and globally significant habitat for birds and marine mammals, including several federally listed species. Villages and communities of the Alaska Peninsula and other areas bordering or near the Basin rely on its natural resources (especially commercial and subsistence fishing) for much of their sustenance and livelihood. The offshore area of the North Aleutian Basin is considered to have important hydrocarbon reserves, especially natural gas. In 2006, the MMS released a draft proposed program, 'Outer Continental Shelf Oil and Gas Leasing Program, 2007-2012' and an accompanying draft programmatic environmental impact statement (EIS). The draft proposed program identified two lease sales proposed in the North Aleutian Basin in 2010 and 2012, subject to restrictions. The area proposed for leasing in the Basin was restricted to the Sale 92 Area in the southwestern portion. Additional EISs will be needed to evaluate the potential effects of specific lease actions, exploration activities, and development and production plans in the Basin. A full range of updated multidisciplinary scientific information will be needed to address oceanography, fate and effects of oil spills, marine ecosystems, fish, fisheries, birds, marine mammals, socioeconomics, and subsistence in the Basin. Scientific staff at Argonne National Laboratory were contracted to assist MMS with identifying and prioritizing information needs related to potential future oil and gas leasing and development activities in the North Aleutian Basin. Argonne focused on three related tasks: (1) identify and gather relevant literature published since 1996, (2) synthesize and

  12. Segmentation pattern and structural complexities in seismogenic extensional settings: The North Matese Fault System (Central Italy)

    Science.gov (United States)

    Ferrarini, Federica; Boncio, Paolo; de Nardis, Rita; Pappone, Gerardo; Cesarano, Massimo; Aucelli, Pietro P. C.; Lavecchia, Giusy

    2017-02-01

    We investigated the northern slope of the Matese Mts. (Molise, Central Italy) with the aim of characterizing the N- to NE-dipping active normal fault system in the Bojano basin, a sector of primary importance from a seismic hazard perspective. We collected field data to define the geometry and segmentation pattern of two sub-systems (Patalecchia-Colle di Mezzo and Bojano-Campochiaro). New evidence of late Quaternary faulting was obtained by exploiting well log interpretations. Kinematic analysis revealed the interaction of pre-Quaternary inherited (mainly E-W-striking) and newly formed (NW-SE-striking) normal faults. Slip accommodation through linkage was clearly noted in the case of the Patalecchia-Colle di Mezzo sub-system. Detailed topographic profiles across the active fault segments provided post-LGM (15 ± 3 kyr) slip rates up to ∼2 mm/yr which agree with the high deformation rates based on different approaches in the literature. Finally, the instrumental seismicity analysis constrained the bottom of the seismogenic layer to depths of 13-14 km, and the gathered information allowed us to reconstruct the North Matese seismogenic source. Its 3D geometry and dimensions agree with both the dimension-magnitude relationships and macroseismic information available for the 1805 earthquake (Mw 6.6), the main historical earthquake to have struck the Bojano basin.

  13. Geochemistry of late Quaternary tephra-sediment sequence from north-eastern Basin of Mexico (Mexico): implications to tephrochronology, chemical weathering and provenance

    OpenAIRE

    Priyadarsi D. Roy; José Luis Arce; Rufino Lozano; M.P. Jonathan; Elena Centeno; Socorro Lozano

    2012-01-01

    A ca.30 m thick tephra-sediment sequence from the north-eastern Basin of Mexico (Pachuca subbasin, central Mexico) is investigated for stratigraphy and multi-element geochemistry to understand the tephrochronology, provenance and conditions of chemical weathering during Late Quaternary. Chemical compositions of tephra layers are compared with products from surrounding volcanic structures (Apan- Tezontepece, Acoculco, Huichapan, Sierra de las Cruces and Tláloc) in order to identify their sourc...

  14. Basin Management under the Global Climate Change (Take North-East Asia Heilongjiang -Amur Basin and Taihu Basin For Example)

    Science.gov (United States)

    Liu, S.; Zhou, Z.; Zhong, G.; Zhang, X.

    2015-12-01

    The impact of global climate change on environment and society causes increasingly concern in different countries around the world. The main climate characteristic values, such as precipitation and temperature, have been changed, which leads to the variation of water resources, especially in large basins. Heilongjiang-Amur Basin and Taihu Basin are two large and important basins in China with large area and population. As global climate change and human activities have siganificant impacts on hydrology and water resources in two basins, the analysis of climate change are of great value. In this study, in Heilongjiang-Amur Basin, precipitation and temperature are investigated and their variation are predicted. And in Taihu Basin, precipitation including plum rain and typhoon, are studied and the variation trend of precipitation is predicted. Hence, the impacts of global climate change are assessed. From the result, it shows that the average temperature will continue to increase, and the precipitation will reduce first and then turn to increase in these two basins. It demonstrates that the water resources have been affected a lot by climate change as well as human activities. And these conclusions are provided as reference for policy makers and basin authorities in water resources management and natural hazards mitigation. Meanwhile, according to basins' particualr characters, the suggestions to future water resources management in two basins are given, and more scientific, comprehensive and sustained managements are required. Especially, in Heilongjiang-Amur River, which is a boundary river between China and Russia, it is very essential to enhance the cooperation between two countries.

  15. Quantitative radiolarian assemblages in surface sediments from the central Indian Basin and their paleomonsoonal significance

    Digital Repository Service at National Institute of Oceanography (India)

    Gupta, S.M.

    The percentage data of 47 radiolarian coarser taxonomic groups in the surface sediments from the central Indian Basin was subjected to cluster and factor analyses. The R-mode cluster analysis resulted in 3 dominant clusters which represent surface...

  16. Chemical characteristics of Central Indian Basin waters during the southern summer

    Digital Repository Service at National Institute of Oceanography (India)

    DeSousa, S.N.; Sardessai, S.; RameshBabu, V.; Murty, V.S.N.; Gupta, G.V.M.

    Chemical properties of the water column were examined at the Indian Deep-sea Environment Experiment (INDEX) site in the Central Indian Basin (CIB), as a part of baseline studies prior to the benthic disturbance experiment for the environmental...

  17. The origin of ferro-manganese oxide coated pumice from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Pearce, N.J.G.; Parthiban, G.; Smith, V.C.; Mudholkar, A.V.; Rao, N.R.

    Pumice clasts, partially and fully coated with ferro-manganese oxide from the Central Indian Ocean Basin (CIOB) were analysed for major, trace and rare earth elements; and glass and mineral grain chemistry to assess their possible source...

  18. Petrology of seamounts in the Central Indian Ocean Basin: Evidence for near-axis origin

    Digital Repository Service at National Institute of Oceanography (India)

    Mukhopadhyay, R.; Batiza, R.; Iyer, S.D.

    Previous studies on the distribution and morphology of ancient seamount chains (>50 Ma) in the Central Indian Ocean basin (CIOB) indicated their generation from the fast spreading Southeast Indian Ridge. The petrology of some of these seamounts...

  19. Ferromanganese nodules and their associated sediments from the Central Indian Ocean Basin: Rare earth element geochemistry

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Rao, Ch.M.; Migdisov, A.A.; Colley, S.; Higgs, N.C.; Demidenko, L.

    The rare earth element (REE) distribution in nine deep-sea ferromanganese nodules and their associated siliceous sediments from the Central Indian Ocean Basin (CIOB) have been studied to elucidate the REE relationship among them. Total REE...

  20. Rare earth element patterns of the Central Indian Basin sediments related to their lithology

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; Roelandts, I.; Sudhakar, M.; Pluger, W.L.

    Rare earth element (REE) concentration have been determined in terrigenous, siliceous (nodule barren and nodule bearing), calcareous, and red clay from the Central Indian Basin. The bulk distribution of REE, and in particular the relative cerium...

  1. Diagenetic remobilization of rare earth elements in a sediment core from the central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Banakar, V.K.

    Rare earth elements (REE) distribution in a 36 cm long sediment box core from the Central Indian Basin is studied. REE concentration is generally higher in the upper oxic zone than in intermediate suboxic zone suggesting REE diffusion upwards...

  2. Variation in size, morphology and chemical composition of polymetallic nodules from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Karisiddaiah, S.M.; Parthiban, G.

    Chemical composition of 613 polymetallic nodules from 150 stations in the Central Indian Ocean Basin (CIOB) are determined and variations in Mn, Fe, Cu, Ni, Co, Zn and moisture content are studied with respect to their size and surface texture...

  3. Categories used to classify the basin-fill deposits in the Central Valley

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset contains the categories used to classify the basin-fill deposits in the Central Valley as either coarse-grained or fine-grained deposits. This...

  4. HYDROLOGY OF CENTRAL GREAT BASIN MEADOW ECOSYSTEMS – EFFECTS OF STREAM INCISION

    Science.gov (United States)

    Riparian wet meadow complexes in the mountains of the central Great Basin are scarce, ecologically important systems that are threatened by stream incision. Our interdisciplinary group has investigated 1) the interrelationships of geomorphology, hydrology, and vegetation; and 2) ...

  5. Assessment of coalbed gas resources of the Central and South Sumatra Basin Provinces, Indonesia, 2016

    Science.gov (United States)

    Schenk, Christopher J.; Klett, Timothy R.; Tennyson, Marilyn E.; Mercier, Tracey J.; Brownfield, Michael E.; Pitman, Janet K.; Gaswirth, Stephanie B.; Finn, Thomas M.

    2016-12-09

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated a mean of 20 trillion cubic feet of undiscovered, technically recoverable coalbed gas resource in the Central and South Sumatra Basin Provinces of Indonesia.

  6. Benthic disturbance and monitoring experiment in the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.; Nath, B.N.

    Environmental impact assessment studies for deep-sea manganese nodule mining have been initiated in the Central indian Ocean Basin since 1995. As a part of the first phase for collecting the benthic baseline data, echosounding, subbottom profiling...

  7. Geochemistry of deep-sea sediment cores from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Mudholkar, A.V.; Pattan, J.N.; Parthiban, G.

    Four sediment cores from the Central Indian Ocean Basin (CIOB) were studied to characterise the coarse fraction (less than 63 mu), transition metal and major oxide contents. Transition metals (Mn, Cu, Ni, Zn) show enrichment towards the surface...

  8. Assessment of undiscovered oil and gas resources of the North Sakhalin Basin Province, Russia, 2011

    Science.gov (United States)

    Klett, T.R.; Schenk, Christopher J.; Wandrey, Craig J.; Charpentier, Ronald R.; Brownfield, Michael E.; Pitman, Janet K.; Pollastro, Richard M.; Cook, Troy A.; Tennyson, Marilyn E.

    2011-01-01

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated volumes of undiscovered, technically recoverable, conventional petroleum resources for the North Sakhalin Basin Province of Russia. The mean volumes were estimated at 5.3 billion barrels of crude oil, 43.8 trillion cubic feet of natural gas, and 0.8 billion barrels of natural gas liquids.

  9. Cultural Resource Investigation of the Goose River Basin, North Dakota

    Science.gov (United States)

    1978-05-12

    Upper Knife-Heart District, North Dakota. Plains Anthropologist, Vol. 17, No. 56, pp. 91-100. 1975, Brain Size and Hominid Evolution. Proceedings of...Scholarships: Associated Women Students of New Mexico State University (1976) Language Competency: Fair in reading, speaking, and writing Spanish Honors

  10. Assessment of undiscovered continuous oil and gas resources in the Dnieper-Donets Basin and North Carpathian Basin Provinces, Ukraine, Romania, Moldova, and Poland, 2015

    Science.gov (United States)

    Klett, Timothy R.; Schenk, Christopher J.; Brownfield, Michael E.; Charpentier, Ronald R.; Mercier, Tracey J.; Leathers-Miller, Heidi M.; Tennyson, Marilyn E.

    2016-11-30

    Using a geology-based methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resources of 13 million barrels of oil and 2,643 billion cubic feet of natural gas in the Dnieper-Donets Basin and North Carpathian Basin Provinces of Ukraine, Romania, Moldova, and Poland.

  11. Marine Ingressive Events Recorded in Epicontinental Sequences:Example from the Cretaceous Songliao Basin of NE China in Comparison with the Triassic Central Europe Basin of SW Germany

    Institute of Scientific and Technical Information of China (English)

    WANG Pujun; LIU Wanzhu; YIN Xiuzhen; SCHNEIDER Werner; MATTERN Frank

    2002-01-01

    Songliao Basin is filled predominantly with continental facies sediments including alluvial fan, fluvial plain, fan delta, lacustrine delta, shore - shallow lacustrine, beach salty flat, semi - deep to deep lacustrine, subaqueous gravity flow,lacustrine swamp and pyroclastic sediments. However, some event units were formed during lake - marine linking periods of the Mid - Cretaceous in the basin, which include black shales with high values for salinity (Sr/Ba) , alkalinity ( Ca + Mg)/(Si + Al) , reducibility (Ni + Zn)/Ga and sulfide sulfur as well as heavy isotopes. The Breitenholz -section to be represented for facies comparison with the Cretaceous evaporitic series in Northeast China is localized in Southwest Germany. Stratigraphically it belongs to the Crabfeld Formation of Keuper of the Germanic Triassic corresponding to Ladinian - Carnian of the international reference scale, and is generally called Lower Gipskeuper. The Germanic Triassic was deposited in the epicontinental (cratonic) central Europe Basin. It covered the area in between Great Britain, North Sea, Poland and Southern Germany. It is composed of cyclic deposits of multicolored mudstones, gypsum/anhydrite, and dolomite beds. The two cases of marine ingression - influenced sequences share some common features.

  12. A potential archive of Pleistocene uplift and erosion in the eastern Nete basin, Campine area, north-eastern Belgium

    Science.gov (United States)

    Beerten, Koen; Leterme, Bertrand

    2013-04-01

    From a geodynamic point of view, the Campine area is situated on the crossroads between distinctive tectonic settings: the subsiding North Sea basin and Roer Valley Graben in the north, and the uplifting Brabant Massif and Ardennes in the south. In general, this has led to overall Cenozoic subsidence of the area and sedimentation of unconsolidated marine sands. However, the morphology of the present-day Nete basin, which is situated in the central and eastern part of the Campine area, is a clear example of an erosional feature and shows evidence of up to 30 m of Quaternary erosion. However, the drivers, timing and rate of landscape development in the Nete basin are poorly constrained. Here, we present and describe geological and geomorphological remnants testifying to past landscape development in the Nete basin, that will help understanding the Quaternary geodynamic evolution (uplift) of the Campine area. The Nete basin is located in northern Belgium and is drained by two small rivers, the Kleine Nete and Grote Nete, that merge into the larger Nete river several km before entering the Lower Scheldt basin. The Nete basin can clearly be identified on topographical maps as a depression, ca. 40 km x 40 km, with valley floors ranging between 10-20 m above sea level (a.s.l.). It is bounded in the north, east and south by erosion resistant geological formations at altitudes between 30 m (north) and 60 m (south). The major direction of drainage is from ENE to WSW and the basin thus opens towards the west. The start of basin development is situated after deposition of Rhine sediments (~ 1 Ma) which form the erosion resistant eastern watershed with the Meuse basin at an altitude of ~ 50 m a.s.l. on top of the Campine Plateau. GIS-based landscape analysis of the topography and the contour map of the Quaternary base confirm the observation that the lowering of the relief from the Campine Plateau down to the floodplain of the Kleine Nete and Grote Nete shows a stepwise

  13. NDT education improvements through the North Central Collaboration for NDT

    Science.gov (United States)

    Larson, B. F.; Wormley, S. J.

    2001-04-01

    The North Central Collaboration for Education in NDE/NDT is an effort aimed at enhancing NDE education and improving articulation between community college technician programs and university technical degree programs. NDT instructors at four community colleges are working with the staff at the Center for NDE at Iowa State University. Through this arrangement, advanced teaching methods and new materials that allow students to learn concepts better and in less time are being developed. For example, materials have been developed that will facilitate the use of an X-ray inspection simulation program in teaching basic radiography. Course materials have been developed and posted on the Internet that allow instructors to use interactive Java applets to better illustrate and explain difficult to grasp concepts. Some of the materials introduce subjects that are not currently extensively taught such as real-time radiography and distance-amplitude-correction (DAC) through curved surfaces. This paper will review NDT technician education, discuss the need for improvement in the methods used to educate technicians and highlight some of the efforts of the collaboration.

  14. Reconstruction of North American drainage basins and river discharge since the Last Glacial Maximum

    Science.gov (United States)

    Wickert, Andrew D.

    2016-11-01

    Over the last glacial cycle, ice sheets and the resultant glacial isostatic adjustment (GIA) rearranged river systems. As these riverine threads that tied the ice sheets to the sea were stretched, severed, and restructured, they also shrank and swelled with the pulse of meltwater inputs and time-varying drainage basin areas, and sometimes delivered enough meltwater to the oceans in the right places to influence global climate. Here I present a general method to compute past river flow paths, drainage basin geometries, and river discharges, by combining models of past ice sheets, glacial isostatic adjustment, and climate. The result is a time series of synthetic paleohydrographs and drainage basin maps from the Last Glacial Maximum to present for nine major drainage basins - the Mississippi, Rio Grande, Colorado, Columbia, Mackenzie, Hudson Bay, Saint Lawrence, Hudson, and Susquehanna/Chesapeake Bay. These are based on five published reconstructions of the North American ice sheets. I compare these maps with drainage reconstructions and discharge histories based on a review of observational evidence, including river deposits and terraces, isotopic records, mineral provenance markers, glacial moraine histories, and evidence of ice stream and tunnel valley flow directions. The sharp boundaries of the reconstructed past drainage basins complement the flexurally smoothed GIA signal that is more often used to validate ice-sheet reconstructions, and provide a complementary framework to reduce nonuniqueness in model reconstructions of the North American ice-sheet complex.

  15. Geochemistry evidence for depositional settings and provenance of Jurassic argillaceous rocks of Jiyuan Basin, North China

    Indian Academy of Sciences (India)

    Yao Meng; Deshun Zheng; Minglong Li

    2017-02-01

    This paper aims to discuss the depositional settings and provenances for the Jurassic in Jiyuan basin, North China, based on the rare earth element (REE) and trace element features of 16 Jurassic argillaceous rock samples from the Anyao, Yangshuzhuang and Ma’ao Formations, respectively. Generally, geochemical analysis results show that chondrite-normalised REE distribution patterns of all the three formations are characterised by light-REE (LREE) enrichment, moderately negative Eu anomalies, slightly negative Ce anomalies, and strong fractionation between LREE and heavy-REE (HREE). Trace element proxies V/(V+Ni), Ceanom index, Ce/La, Sr/Ba, and Sr/Cu indicate a weak oxidation–reduction environment, progressively decreasing reducibility and water depth from the bottom up during Jurassic in Jiyuan basin. Palaeoclimate varied from humid in the Early Jurassic to arid in the Middle Jurassic, corresponding with the variations of palaeoredox and palaeosalinity. The provenances of Jurassic rocks in Jiyuan basin are mainly from felsic sources related to active continental margin and continental island arc. The Early–Middle Jurassic (Anyao and Yangshuzhuang Formations) provenances are mainly derived from North Qinling and partially from the eroded recycled felsic sedimentary covers of Taihang Mountain. In the late stage of Middle Jurassic (Ma’ao Formation), Taihang Mountain has been the primary source to Jiyuan basin. We conclude that the Jurassic rocks of Jiyuan basin reveal the progressive uplift and denudation processes of the Taihang Mountain.

  16. Folded Lithospheric Basins in Central Asia: Altai-Sayan and Tien Shan basins in a folding lithosphere

    Science.gov (United States)

    Delvaux, Damien; Cloetingh, Sierd; Beekman, Fred; Sokoutis, Dimitrios; Burov, Evguenii; Buslov, Misha; Abdrakhmatov, Kanatbeck

    2014-05-01

    Central Asia is a classic example for continental lithospheric folding. In particular, the Altay-Sayan belt in South-Siberia and the Kyrgyz Tien Shan display a special mode of lithospheric deformation, involving decoupled lithospheric mantle folding and upper crustal folding and faulting. A review of the paleostress data and tectono-stratigraphic evolution of the Kurai-Chuya basin in Siberian Altai, Zaisan basin in Kazakh South Altai and Issyk-Kul basin in Kyrgyz Tien Shan suggests that these basins were initiated in an extensional context and later inverted by a combination of fault-controlled deformation and flexural folding. They deformed by a combination of lithospheric buckling inducing surface tilting, uplift and subsidence, together with upper crustal fault-controlled deformation. They are good examples of Folded Lithospheric Basins (FLB) which typically form in a buckling lithosphere. Their characteristic basin fill and symmetry, inner structure, folding wavelength and amplitude, thermal regime and time frame are examined in relation to basement structure, stress field, strain rate, timing of deformation, and compared to existing modelling results. Both regions of active lithospheric folding have a heterogeneous crust with a long history of accretion-collision, subsequently reactivated as a far-field effect of the Indian-Eurasian collision. Thanks to the youthfulness of the tectonic deformation in this region (peak deformation in late Pliocene - early Pleistocene), the surface expression of lithospheric deformation is well documented by the surface topography and superficial tectonic structures.

  17. Pesticides detected in surface waters and fish of the Red River of the North drainage basin

    Science.gov (United States)

    Brigham, Mark E.

    1994-01-01

    The Red River of the North drainage basin (herein referred to as Red River Basin) within the United States is a study unit under the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) program. The overall goals of this program, initiated to better define the status and trends of the Nation’s water quality, are to address regional and national water-quality issues in a nationally consistent manner. Pesticide contamination of surface water and fish is one focus of this program.

  18. Tectono-stratigraphic evolution and crustal architecture of the Orphan Basin during North Atlantic rifting

    Science.gov (United States)

    Gouiza, Mohamed; Hall, Jeremy; Welford, J. Kim

    2016-06-01

    The Orphan Basin is located in the deep offshore of the Newfoundland margin, and it is bounded by the continental shelf to the west, the Grand Banks to the south, and the continental blocks of Orphan Knoll and Flemish Cap to the east. The Orphan Basin formed in Mesozoic time during the opening of the North Atlantic Ocean between eastern Canada and western Iberia-Europe. This work, based on well data and regional seismic reflection profiles across the basin, indicates that the continental crust was affected by several extensional episodes between the Jurassic and the Early Cretaceous, separated by events of uplift and erosion. The preserved tectono-stratigraphic sequences in the basin reveal that deformation initiated in the eastern part of the Orphan Basin in the Jurassic and spread towards the west in the Early Cretaceous, resulting in numerous rift structures filled with a Jurassic-Lower Cretaceous syn-rift succession and overlain by thick Upper Cretaceous to Cenozoic post-rift sediments. The seismic data show an extremely thinned crust (4-16 km thick) underneath the eastern and western parts of the Orphan Basin, forming two sub-basins separated by a wide structural high with a relatively thick crust (17 km thick). Quantifying the crustal architecture in the basin highlights the large discrepancy between brittle extension localized in the upper crust and the overall crustal thinning. This suggests that continental deformation in the Orphan Basin involved, in addition to the documented Jurassic and Early Cretaceous rifting, an earlier brittle rift phase which is unidentifiable in seismic data and a depth-dependent thinning of the crust driven by localized lower crust ductile flow.

  19. Hydrologic Setting and Conceptual Hydrologic Model of the Walker River Basin, West-Central Nevada

    Science.gov (United States)

    Lopes, Thomas J.; Allander, Kip K.

    2009-01-01

    The Walker River is the main source of inflow to Walker Lake, a closed-basin lake in west-central Nevada. Between 1882 and 2008, agricultural diversions resulted in a lake-level decline of more than 150 feet and storage loss of 7,400,000 acre-ft. Evaporative concentration increased dissolved solids from 2,500 to 17,000 milligrams per liter. The increase in salinity threatens the survival of the Lahontan cutthroat trout, a native species listed as threatened under the Endangered Species Act. This report describes the hydrologic setting of the Walker River basin and a conceptual hydrologic model of the relations among streams, groundwater, and Walker Lake with emphasis on the lower Walker River basin from Wabuska to Hawthorne, Nevada. The Walker River basin is about 3,950 square miles and straddles the California-Nevada border. Most streamflow originates as snowmelt in the Sierra Nevada. Spring runoff from the Sierra Nevada typically reaches its peak during late May to early June with as much as 2,800 cubic feet per second in the Walker River near Wabuska. Typically, 3 to 4 consecutive years of below average streamflow are followed by 1 or 2 years of average or above average streamflow. Mountain ranges are comprised of consolidated rocks with low hydraulic conductivities, but consolidated rocks transmit water where fractured. Unconsolidated sediments include fluvial deposits along the active channel of the Walker River, valley floors, alluvial slopes, and a playa. Sand and gravel deposited by the Walker River likely are discontinuous strata throughout the valley floor. Thick clay strata likely were deposited in Pleistocene Lake Lahontan and are horizontally continuous, except where strata have been eroded by the Walker River. At Walker Lake, sediments mostly are clay interbedded with alluvial slope, fluvial, and deltaic deposits along the lake margins. Coarse sediments form a multilayered, confined-aquifer system that could extend several miles from the shoreline

  20. Geophysical Evidence about of Continental Margin Central in the Basin of Cuba

    Directory of Open Access Journals (Sweden)

    María Caridad Rifá Hernández

    2013-06-01

    Full Text Available The Central basin of Cuba, bounded by the Zaza Tuinicú and La Trocha faults, is the site of threesmall oil fields and many showings, both at the surface and in wells. The petroleum is found mainlyin volcano-sedimentary rocks and sediments laid down during the Cuban progeny. With contrastswith petroleum on the north coast of the country in the intensely folded sediments of the continentalmargin in the Provinces of Havana, Mayabeque and Matanzas. The presence of these sedimentsbeneath the Cretaceous volcanic arc has been proposed based on geological evidence. Nevertheless,these sediments have yet to be encountered in the numerous drill holes present in the area. Thisstudy offers geophysical evidence pointing to the presence of the Placetas and Camajuaní tectonicstratigraphicunits at no great depths. The present analysis given here takes into account a geologicalinterpretation as well as both regional and local gravitational, magnetic and seismic studies; well datais also included as an integral part of the study. Finally, after presenting evidence based on seismicexploration and taking into account the limitations of this method applied to the Cuban fold belt, wepropose the use of more modern techniques to locate raised portions of the Placetas and Camajuanítectono-stratigraphic units.

  1. Miocene sediment dispersal in the central Española basin, Rio Grande rift, New Mexico, U.S.A.

    Science.gov (United States)

    Cavazza, William

    1986-12-01

    The central Española basin in north-central New Mexico represents one of the best opportunities to examine deposits related to the development of the Rio Grande rift. The Miocene Tesuque Formation represents the bulk of the Española basin fill. It is composed of a 2000-2500 m thick sequence of alluvial-fluvial and, subordinately, lacustrine deposits with numerous interbedded ash-fall tuff layers. The overall detrital composition of the Tesuque Formation is very similar throughout the central Española basin. Provenance is primarily from basement uplifts composed of Precambrian igneous and high-grade metamorphic rocks. Nevertheless, the combined use of paleocurrent analysis, and sandstone and conglomerate petrology allows a detailed reconstruction of the sediment paleodispersal system. Two sedimentary provinces are present within the Tesuque Formation: Province A, present in the eastern, central and southern portions of the study area, has a predominantly plutoniclastic and metamorphiclastic composition, and shows systematic paleocurrents toward the west. The sediments were derived from the Precambrian-cored Santa Fe block of the Sangre de Cristo Mountains, located directly to the east of the study area. Province B, present only in the northwestern portion of the study area, is characterized by a minor but significant amount of volcaniclastic and sedimentaclastic detritus, and shows consistent SSW-directed paleocurrents. The source area was possibly located in the area of the Taos Plateau and Latir volcanic fields. An intermediate narrow and discontinuous belt (province A + B) represents a hybrid province, where directional and compositional parameters are gradational.

  2. The genetic impact of the lake chad basin population in North Africa as documented by mitochondrial diversity and internal variation of the L3e5 haplogroup.

    Science.gov (United States)

    Podgorná, Eliška; Soares, Pedro; Pereira, Luísa; Cerný, Viktor

    2013-11-01

    The presence of sub-Saharan L-type mtDNA sequences in North Africa has traditionally been explained by the recent slave trade. However, gene flow between sub-Saharan and northern African populations would also have been made possible earlier through the greening of the Sahara resulting from Early Holocene climatic improvement. In this article, we examine human dispersals across the Sahara through the analysis of the sub-Saharan mtDNA haplogroup L3e5, which is not only commonly found in the Lake Chad Basin (∼17%), but which also attains nonnegligible frequencies (∼10%) in some Northwestern African populations. Age estimates point to its origin ∼10 ka, probably directly in the Lake Chad Basin, where the clade occurs across linguistic boundaries. The virtual absence of this specific haplogroup in Daza from Northern Chad and all West African populations suggests that its migration took place elsewhere, perhaps through Northern Niger. Interestingly, independent confirmation of Early Holocene contacts between North Africa and the Lake Chad Basin have been provided by craniofacial data from Central Niger, supporting our suggestion that the Early Holocene offered a suitable climatic window for genetic exchanges between North and sub-Saharan Africa. In view of its younger founder age in North Africa, the discontinuous distribution of L3e5 was probably caused by the Middle Holocene re-expansion of the Sahara desert, disrupting the clade's original continuous spread.

  3. Tropical Cyclone Exposure for U.S. waters within the North Atlantic Ocean basin, 1900-2013

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent modeled, historical exposure of U.S. offshore and coastal waters to tropical cyclone activity within the North Atlantic Ocean basin. BOEM Outer...

  4. Top of Head Scarp and Internal Scarps for Landslide Deposits in the Little North Santiam River Basin, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Data points represent head scarps, flank scarps, and minor internal scarps (linear) associated with landslide deposits in the Little North Santiam River Basin,...

  5. Structural Geology of Daba Shan and its Tectonic Relationships with the Sichuan Basin and Central China Orogen, China

    Science.gov (United States)

    Guo, X.; Kusky, T.; Li, Z.

    2008-12-01

    Daba Shan is a fold-and-thrust belt located on the northeastern margin of the Sichuan Basin, central China orogen. It is the transitional zone between the Sichuan Basin and Qinling orogenic belt, and it is located in the middle part of the Mianlu suture zone which is the boundary between the Qinling orogenic belt and Yangtze block. Numerous faults and fault-related folds are well preserved in Daba Shan. It is a natural laboratory to carry out fold-thrust belt research on relationships between the Qingling orogen and subsidence in the Sichuan basin. In this talk, I will introduce the general geologic background about and around Daba Shan, including the geologic history of the central China orogen, the formation and development of the Mianlue suture, and the most popular ideas about the geodynamic evolution of Daba Shan, as well as its geologic position between the Sichuan Basin and North China craton and its relative geodynamic relationship with Mianlue suture zone. Field investigations have shown the different fault-related structure styles, e.g. fault-bend fold, fault-propagation fold, duplex structure across the orogen. In addition, a major extensional detachment fault, the Chengkou fault, crops out in the center of the orogen and dips beneath northern Daba Shan fold-thrust belt and Mianlue suture. It is so impressive of the typical and complex geological structure scenarios there, which were mostly caused by the collisional and post-collisional activities between Qinling micro-continent and Yangtze block since mid-Triassic time. Daba Shan has very important tectonic and economic significance in China. Although geoscientists have been working on the Sichuan Basin and central China orogen for many years, Daba Shan has gained little attention. These years, with gas and oil exploration development in foreland basin and fold-thrust belt areas, especially after the discovery of carbonate strata in Daba Shan, its economic potential has become more prominent. This

  6. Understanding volcanism at the PETM: Abundant volcanic ash layers in the Central Tertiary Basin of Spitsbergen, Svalbard

    Science.gov (United States)

    Jones, Morgan; Eliassen, Gauti; Svensen, Henrik; Jochmann, Malte; Friis, Bjarki; Jerram, Dougal; Planke, Sverre

    2014-05-01

    During the early Tertiary, Svalbard developed a fold-thrust belt on its western margin with an associated foreland basin in the central-south of what is now Spitsbergen. This Central Tertiary Basin (CTB) is a syn-orogenic sedimentary basin in a strike-slip regime. The CTB contains the ~1900 m thick Van Mijenfjorden group, a dominantly sandstone-shale succession that was deposited in a North-South extending basin. Sediments in this group display evidence of major transgressive-regressive cycles related to local tectonics and eustatic sea level change. This basin is ideal for study as it has been extensively cored for coal prospecting, allowing a suite of sedimentary logs across the basin to be considered. Prominent marker beds in this sedimentary sequence are 1-30 cm thick bentonites, formed from the chemical weathering of volcanic tuff deposits. In this study, we focus on 8 sedimentary logs across the CTB, spanning the Palaeocene to lower Eocene in age. Bentonites are common in the Palaeocene cores (Basilika and Grumantbyen formations), while rarer but still occasionally present in the Eocene Frysjaodden formation. The cores had between 3-12 observable bentonite layers that showed large variations in preservation and subsequent reworking. Roots and other finer organic material were common, especially when the bentonites were found next to coal seams. Geochemical affinities between ash layers were investigated to identify basin-wide depositional events, with the aim of elucidating the provenance of these ashes. This sedimentary sequence is of broader interest as it covers the Palaeocene-Eocene thermal maximum (PETM), an extreme global warming event driven by large releases to the atmosphere of CO2 and/or CH4, evidenced by a negative carbon isotope excursion in both the ocean and atmosphere. Potential sources include volcanism and associated gas release from intruded sediments, CH4 hydrate dissociation, and/or the oxidation of organic matter. These formations are

  7. Modal Composition and Age of Intrusions in North-Central and Northeast Nevada

    Science.gov (United States)

    du Bray, Edward A.; Crafford, A. Elizabeth Jones

    2007-01-01

    Introduction Data presented in this report characterize igneous intrusions of north-central and northeast Nevada and were compiled as part of the Metallogeny of the Great Basin project conducted by the U.S. Geological Survey (USGS) between 2001 and 2007. The compilation pertains to the area bounded by lats 38.5 and 42 N., long 118.5 W., and the Nevada-Utah border (fig. 1). The area contains numerous large plutons and smaller stocks but also contains equally numerous smaller, shallowly emplaced intrusions, including dikes, sills, and endogenous dome complexes. Igneous intrusions (hereafter, intrusions) of multiple ages are major constituents of the geologic framework of north-central and northeast Nevada (Stewart and Carlson, 1978). Mesozoic and Cenozoic intrusions are particularly numerous and considered to be related to subduction along the west edge of the North American plate during this time. Henry and Ressel (2000) and Ressel and others (2000) have highlighted the association between magmatism and ore deposits along the Carlin trend. Similarly, Theodore (2000) has demonstrated the association between intrusions and ore deposits in the Battle Mountain area. Decades of geologic investigations in north-central and northeast Nevada (hereafter, the study area) demonstrate that most hydrothermal ore deposits are spatially, and probably temporally and genetically, associated with intrusions. Because of these associations, studies of many individual intrusions have been conducted, including those by a large number of Master's and Doctoral thesis students (particularly University of Nevada at Reno students and associated faculty), economic geologists working on behalf of exploration and mining companies, and USGS earth scientists. Although the volume of study area intrusions is large and many are associated with ore deposits, no synthesis of available data that characterize these rocks has been assembled. Compilations that have been produced for intrusions in Nevada

  8. Remote Sensing Observations of Snow and Soil Moisture for Snowmelt Flood Predictions in the Red River of the North Basin

    Science.gov (United States)

    Tuttle, S. E.; Jacobs, J. M.; Vuyovich, C.; Cho, E.; Restrepo, P. J.; Jia, X.; Cosh, M. H.; Deweese, M. M.; Connelly, B.; Buan, S.

    2015-12-01

    The northward-flowing Red River of the North Basin (RRB), located in eastern North Dakota and western Minnesota, is vulnerable to frequent floods due to its flat terrain and low permeability soil. A vast majority of floods in the basin occur during the snowmelt season, when the winter snowpack thaws and spring rains fall onto saturated soils. This causes the Red River to spill over shallow banks and across the floodplain. The region has sparse in situ observations of snow and soil moisture, making flood prediction in the RRB difficult. Remote sensing data can help to capture magnitude, timing, and spatial distribution of watershed scale snow, soil moisture, and snowmelt parameters in the RRB, which will allow for better characterization of the watershed's hydrologic state. This research examines snow water equivalent (SWE; from the AMSR-E, AMSR2, and SSM/I satellite instruments), soil moisture (from AMSR-E, SMOS, and SMAP), and snow covered area (SCA; from MODIS), along with modeled SWE and snow depth from NOAA's National Operational Hydrologic Remote Sensing Center (NOHRSC) SNOw Data Assimilation System (SNODAS). These data are compared with observations from local and federal snow surveys, NOHRSC Airborne Gamma Radiation Snow Survey Program flights, NOAA National Climate Data Center (NCDC) cooperative network sites, Natural Resource Conservation Service (NRCS) Soil Climate Analysis Network (SCAN) sites, and the North Central River Forecast Center's (NCRFC) model states, in order to determine data quality as well as strengths and weaknesses of satellite observations for RRB flood forecasting. Future analyses will include evaluation of freeze/thaw state information from the Soil Moisture Active-Passive (SMAP) satellite, and explore the potential for flood forecasting improvement by updating state variables of the NOAA National Weather Service (NWS) operational forecasting models with remotely sensed fields.

  9. Reexamination of the geological structure of the North German Basin in Lower Saxony

    Science.gov (United States)

    Rienäcker, Julia; Sattler, Sabine

    2016-04-01

    The North German Basin (NGB), as part of the Southern Permian Basin in Europe, extends from the North Sea, across Denmark, the Netherlands through Northern Germany, to Poland. It contains sediments from the Lower Permian to the Quaternary, and experienced a minimum subsidence of 2000 m from the Permian to the Mesozoic. This was followed by uplift during Late Cretaceous-Early Cenozoic inversion. The hundreds of meters thick and mobile Zechstein salt of Late Permian was remobilized in several phases to form complex salt structures. The salt moved laterally and vertically thus creating salt pillows and tall asymmetrical salt diapirs, some of which broke through the overburden until they were exposed at the paleo-surface. Salt structures influenced both the sedimentation and structural style throughout the NGB. Within the joint project TUNB (Deeper Underground North German Basin), 2-D/3-D seismic datasets, borehole data, structural maps and the existing 3-D geological model of Lower Saxony, will be used to create a new, detailed, geological 3-D model of the Lower Saxony part of the NGB. This allows new insights into the interplay between salt tectonics, sedimentation and tectonic movement, and in particular may help to resolve issues regarding the influence of the Zechstein salt on the sediment distribution. We show the different structural styles of important reservoir formations for, e.g., hydrocarbons, geothermal energy and gas storage, such as the Middle Buntsandstein, Rhaetkeuper, Middle Jurassic, and Lower Cretaceous, especially related to salt structures.

  10. Reservoir heterogeneity in Carter Sandstone, North Blowhorn Creek oil unit and vicinity, Black Warrior Basin, Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Kugler, R.L.; Pashin, J.C.

    1992-05-01

    This report presents accomplishments made in completing Task 3 of this project which involves development of criteria for recognizing reservoir heterogeneity in the Black Warrior basin. The report focuses on characterization of the Upper Mississippian Carter sandstone reservoir in North Blowhorn Creek and adjacent oil units in Lamar County, Alabama. This oil unit has produced more than 60 percent of total oil extracted from the Black Warrior basin of Alabama. The Carter sandstone in North Blowhorn Creek oil unit is typical of the most productive Carter oil reservoirs in the Black Warrior basin of Alabama. The first part of the report synthesizes data derived from geophysical well logs and cores from North Blowhorn Creek oil unit to develop a depositional model for the Carter sandstone reservoir. The second part of the report describes the detrital and diagenetic character of Carter sandstone utilizing data from petrographic and scanning electron microscopes and the electron microprobe. The third part synthesizes porosity and pore-throat-size-distribution data determined by high-pressure mercury porosimetry and commercial core analyses with results of the sedimentologic and petrographic studies. The final section of the report discusses reservoir heterogeneity within the context of the five-fold classification of Moore and Kugler (1990).

  11. Unconformity structures controlling stratigraphic reservoirs in the north-west margin of Junggar basin, North-west China

    Science.gov (United States)

    Wu, Kongyou; Paton, Douglas; Zha, Ming

    2013-03-01

    Tectonic movements formed several unconformities in the north-west margin of the Junggar basin. Based on data of outcrop, core, and samples, the unconformity is a structural body whose formation associates with weathering, leaching, and onlap. At the same time, the structural body may be divided into three layers, including upper layer, mid layer, and lower layer. The upper layer with good primary porosity serves as the hydrocarbon migration system, and also accumulates the hydrocarbon. The mid layer with compactness and ductility can play a role as cap rock, the strength of which increases with depth. The lower layer with good secondary porosity due to weathering and leaching can form the stratigraphic truncation traps. A typical stratigraphic reservoir lying in the unconformity between the Jurassic and Triassic in the north-west margin of the Junggar basin was meticulously analyzed in order to reveal the key controlling factors. The results showed that the hydrocarbon distribution in the stratigraphic onlap reservoirs was controlled by the onlap line, the hydrocarbon distribution in the stratigraphic truncation reservoirs was confined by the truncation line, and the mid layer acted as the key sealing rock. So a conclusion was drawn that "two lines (onlap line and truncation line) and a body (unconformity structural body)" control the formation and distribution of stratigraphic reservoirs.

  12. Unconformity structures controlling stratigraphic reservoirs in the north-west margin of Junggar basin, North-west China

    Institute of Scientific and Technical Information of China (English)

    Kongyou WU; Douglas PATON; Ming ZHA

    2013-01-01

    Tectonic movements formed several unconformities in the north-west margin of the Junggar basin.Based on data of outcrop,core,and samples,the unconformity is a structural body whose formation associates with weathering,leaching,and onlap.At the same time,the structural body may be divided into three layers,including upper layer,mid layer,and lower layer.The upper layer with good primary porosity serves as the hydrocarbon migration system,and also accumulates the hydrocarbon.The mid layer with compactness and ductility can play a role as cap rock,the strength of which increases with depth.The lower layer with good secondary porosity due to weathering and leaching can form the stratigraphic truncation traps.A typical stratigraphic reservoir lying in the unconformity between the Jurassic and Triassic in the north-west margin of the Junggar basin was meticulously analyzed in order to reveal the key controlling factors.The results showed that the hydrocarbon distribution in the stratigraphic onlap reservoirs was controlled by the onlap line,the hydrocarbon distribution in the stratigraphic truncation reservoirs was confined by the truncation line,and the mid layer acted as the key sealing rock.So a conclusion was drawn that "two lines (onlap line and truncation line) and a body (unconformity structural body)" control the formation and distribution of stratigraphic reservoirs.

  13. Two-stage formation model of the Junggar basin basement: Constraints to the growth style of Central Asian Orogenic Belt

    Science.gov (United States)

    He, Dengfa

    2016-04-01

    Junggar Basin is located in the central part of the Central Asian Orogenic Belt (CAOB). Its basement nature is a highly controversial scientific topic, involving the basic style and processes of crustal growth. Some researchers considered the basement of the Junggar Basin as a Precambrian continental crust, which is not consistent with the petrological compositions of the adjacent orogenic belts and the crust isotopic compositions revealed by the volcanic rocks in the basin. Others, on the contrary, proposed an oceanic crust basement model that does not match with the crustal thickness and geophysical characteristics of the Junggar area. Additionally, there are several viewponits, such as the duplex basement with the underlying Precambrian crystalline rocks and the overlying pre-Carboniferous folded basement, and the collaged basement by the Precambrian micro-continent block in the central part and the Hercynian accretionary folded belts circling it. Anyway, it is necessary to explain the property of basement rock, its strong inhomogeneous compositions as well as the geophysical features. In this paper, based on the borehole data from more than 300 industry wells drilled into the Carboniferous System, together with the high-resolution gravity and magnetic data (in a scale of 1:50,000), we made a detailed analysis of the basement structure, formation timing and processes and its later evolution on a basis of core geochemical and isotopic analysis. Firstly, we defined the Mahu Pre-Cambrian micro-continental block in the juvenile crust of Junggar Basin according to the Hf isotopic analysis of the Carboniferous volcanic rocks. Secondly, the results of the tectonic setting and basin analysis suggest that the Junggar area incorporates three approximately E-W trending island arc belts (from north to south: Yemaquan- Wulungu-Chingiz, Jiangjunmiao-Luliang-Darbut and Zhongguai-Mosuowan- Baijiahai-Qitai island arcs respectively) and intervened three approximately E-W trending

  14. FORMATIVE MECHANISM OF AKAISHI MOUNTAINS AND ENREI BASIN IN CENTRAL JAPAN

    Institute of Scientific and Technical Information of China (English)

    Yasu'uchi KUBOTA; Takao YANO

    2001-01-01

    @@ 1 Introduction It is common in mobile belts that uplifting mountains are neighbored by synchronously subsiding basins.The coupling mechanism of such subsidence and uplift is an important target to clarify the dynamics of mobile belts.We investigate the coupled mountain uplift and basin subsidence in the Central Japan highland,the junction of three island arcs (the Northeast Japan,the Southwest Japan and the Izu-Ogasawara arcs).The highland over 3 000 m in height is composed of mountain ranges,plateaus and intramountain basins (Fig.1).

  15. FORMATIVE MECHANISM OF AKAISHI MOUNTAINS AND ENREI BASIN IN CENTRAL JAPAN

    Institute of Scientific and Technical Information of China (English)

    Yasu'uchi; KUBOTA; Takao; YANO

    2001-01-01

    1 Introduction  It is common in mobile belts that uplifting mountains are neighbored by synchronously subsiding basins.The coupling mechanism of such subsidence and uplift is an important target to clarify the dynamics of mobile belts.We investigate the coupled mountain uplift and basin subsidence in the Central Japan highland,the junction of three island arcs (the Northeast Japan,the Southwest Japan and the Izu-Ogasawara arcs).The highland over 3 000 m in height is composed of mountain ranges,plateaus and intramountain basins (Fig.1).……

  16. Multiple provenance of rift sediments in the composite basin-mountain system: Constraints from detrital zircon U-Pb geochronology and heavy minerals of the early Eocene Jianghan Basin, central China

    Science.gov (United States)

    Wu, Lulu; Mei, Lianfu; Liu, Yunsheng; Luo, Jin; Min, Caizheng; Lu, Shengli; Li, Minghua; Guo, Libin

    2017-03-01

    Zircon U-Pb geochronology and heavy minerals are used in combination to provide valuable insights into the provenance of the early Eocene Jianghan Basin, central China. Five samples for zircon U-Pb dating and eighty-five samples for heavy mineral analysis were collected from drill cores or cuttings of the Xingouzui Formation. Most analyzed zircons are of magmatic origin, with oscillatory zoning. Detrital zircons from sample M96 located on eastern basin have two dominant age groups of 113-158 Ma and 400-500 Ma, and the other samples located on southern basin have three prominent age populations at 113-158 Ma, 400-500 Ma and 700-1000 Ma. Samples on different parts of the basin show distinct differences in heavy mineral compositions and they apparently divide into two groups according to the content of rutile (higher or lower than 4%). The spatial variations of zircon-tourmaline-rutile (ZTR) indices are marked by some noticeable increasing trends from basin margins to the inner part of the basin. Compared with the potential source areas, this study clarifies the multiple source characteristics of the Jianghan basin in the composite basin-mountain system. The majority of clastic material was supplied from the north source area through rift-trough sediment-transport pathways, and the eastern, southern and northwestern source areas also contributed detritus to the basin. This clastic material is broadly dispersed in the basin. The early Eocene paleogeography implies that rift architecture and rifting process had an important influence on sediment dispersal. This study shows that integrated zircon U-Pb geochronology and heavy mineral analysis is a useful and powerful method to identify sediment provenance.

  17. River Gain and Loss Studies for the Red River of the North Basin, North Dakota and Minnesota

    Science.gov (United States)

    Williams-Sether, Tara

    2004-01-01

    The Dakota Water Resources Act passed by the U.S. Congress in 2000 authorized the Secretary of the Interior to conduct a comprehensive study of future water-quantity and -quality needs of the Red River of the North (Red River) Basin in North Dakota and of possible options to meet those water needs. To obtain the river gain and loss information needed to properly account for available streamflow within the basin, available river gain and loss studies for the Sheyenne, Turtle, Forest, and Park Rivers in North Dakota and the Wild Rice, Sand Hill, Clearwater, South Branch Buffalo, and Otter Tail Rivers in Minnesota were reviewed. Ground-water discharges for the Sheyenne River in a reach between Lisbon and Kindred, N. Dak., were about 28.8 cubic feet per second in 1963 and about 45.0 cubic feet per second in 1986. Estimated monthly net evaporation losses for additional flows to the Sheyenne River from the Missouri River ranged from 1.4 cubic feet per second in 1963 to 51.0 cubic feet per second in 1976. Maximum water losses for a reach between Harvey and West Fargo, N. Dak., for 1956-96 ranged from about 161 cubic feet per second for 1976 to about 248 cubic feet per second for 1977. Streamflow gains of 1 to 1.5 cubic feet per second per mile were estimated for the Wild Rice, Sand Hill, and Clearwater Rivers in Minnesota. The average ground-water discharge for a 5.2-mile reach of the Otter Tail River in Minnesota was about 14.1 cubic feet per second in August 1994. The same reach lost about 14.1 cubic feet per second between February 1994 and June 1994 and about 21.2 cubic feet per second between August 1994 and August 1995.

  18. Life history of the striped newt at a north-central Florida breeding pond

    Science.gov (United States)

    Johnson, S.A.

    2002-01-01

    I studied the life history of Striped Newts (Notophthalmus perstriatus) at a breeding pond in north-central Florida. Newts were captured in pitfall traps at a drift-fence as they migrated into and out of the pond basin. During the 2-year study, I recorded 10,290 captures (8,127 individuals) of newts at the drift-fence. Newts were active during each month of the study, but there were four peak activity periods, each of which included immigration and emigration events. Immigration events were almost exclusively comprised of adults, whereas emigration events were comprised of adults and recently transformed larvae. I documented 5,296 recently transformed, immature larvae (efts) and 435 recently transformed mature larvae (paedomorphs) during four distinct periods of emigration. Efts matured in the uplands before returning to the pond to breed. In the uplands, male efts (n = 16) grew 0.0183 mm/day on average, whereas average female (n = 24) growth was 0.0167 mm/day. Immigrating adults of both sexes were significantly smaller than emigrating adults. Emigrating efts were smallest, followed by emigrating paedomorphs, immigrating adults, then emigrating adults. The overall adult sex ratio was 1:1.25 (m:f). Sex ratio of emigrating paedomorphs was highly skewed towards females, with one male for every 4.43 females. Newts tended to move during wetter periods, and captures were significantly correlated with rainfall, but rainfall was a poor predictor of the magnitude of newt movements.

  19. Evaluation of low-temperature geothermal potential in north-central Box Elder County, Utah

    Energy Technology Data Exchange (ETDEWEB)

    Davis, M.C.; Kolesar, P.T.

    1984-12-01

    The low-temperature geothermal resources of north-central Box Elder County, Utah were assessed. Exploration techniques used included chemical analyses of water from wells and springs, temperature surveys, and temperature-depth measurements in unused wells within the study area. The highest water temperatures (31/sup 0/, 30/sup 0/, and 29/sup 0/C) recorded in this research were located in three separate geographic regions, suggesting that no single warm water occurrence dominates the study area. Total dissolved solid (TDS) concentrations ranged from 294 to 11,590 mg/l. Areas of warm water occurrences generally had TDS values of greater than 1100 mg/l. Reservoir temperatures were estimated using chemical geothermometers. Calculated temperatures ranged between 50/sup 0/ and 100/sup 0/C. Temperature-depth measurements were logged in 16 unused wells. Thermal gradients calculated from the profiles ranged from isothermal to 267/sup 0/C/km. The background gradient for the study area appears to be slightly above the average Basin and Range gradient of 35/sup 0/C/km. The highest gradients were calculated for the area approximately eight kilometers west of Snowville, Utah, which is also an area of warm water. 61 refs., 15 figs., 6 tabs.

  20. Depositional sequence evolution, Paleozoic and early Mesozoic of the central Saharan platform, North Africa

    Energy Technology Data Exchange (ETDEWEB)

    Sprague, A.R.G. (Exxon Production Research Co., Houston, TX (United States))

    1991-08-01

    Over 30 depositional sequences have been identified in the Paleozoic and lower Mesozoic of the Ghadames basin of eastern Algeria, southern Tunisia, and western Libya. Well logs and lithologic information from more than 500 wells were used to correlate the 30 sequences throughout the basin (total area more than 1 million km{sup 2}). Based on systematic change in the log response of strata in successively younger sequences, five groups of sequences with distinctive characteristics have been identified: Cambro-Ordivician, Upper Silurian-Middle Devonian, Upper Devonian, Carboniferous, and Middle Triassic-Middle Jurassic. Each sequence group is terminated by a major, tectonically enhanced sequence boundary that is immediately overlain (except for the Carboniferous) by a shale-prone interval deposited in response to basin-wide flooding. The four Paleozoic sequence groups were deposited on the Saharan platform, a north facing, clastic-dominated shelf that covered most of North Africa during the Paleozoic. The sequence boundary at the top of the Carboniferous sequence group is one of several Permian-Carboniferous angular unconformities in North Africa related to the Hercynian orogeny. The youngest sequence group (Middle Triassic to Middle Jurassic) is a clastic-evaporite package that onlaps southward onto the top of Paleozoic sequence boundary. The progressive changes from the Cambrian to the Jurassic, in the nature of the Ghadames basin sequences is a reflection of the interplay between basin morphology and tectonics, vegetation, eustasy, climate, and sediment supply.

  1. Slope instability in the Bastardo Basin (Umbria, Central Italy – The landslide of Barattano

    Directory of Open Access Journals (Sweden)

    C. Cencetti

    2003-01-01

    Full Text Available The Bastardo Basin is one of the classics Apenninic intermontane basins of central Italy. They are en-closed tectonic basins (graben and semigraben with high anthropization, but with high vulnerability, too (seismic, hydrogeological and geomorphological. The paper concerns some aspects about slope instability in the Bastardo Basin as part of a wider research, which aims to actually define the characteristics of the liability to landslides of the Apenninic intermontane basins. In particular lithological, stratigraphical and hydrogeological conditions are analysed under which a landslide near village of Barattano has developed. This mass movement, at different times, produced partial or total occlusion of the torrent Puglia. Here geognostic investigations together with laboratory tests and subsequent monitoring of landslide area were carried out.  A back analysis, based on limit equilibrium solutions for the factor of safety of the slope, provided the residual strenght properties of the soil mass along the sliding surface.   The landslide of Barattano is representative of a very frequent situation (in terms of type, factors and causes of the movement, possible development of the movement not only within Bastardo Basin, but in general within Apenninic intermontane basins, too.  The study of landslide and the design of appropriate remedial measures are of great importance in terms of prevention and mitigation of geologic-hydraulic risk in Apenninic intermontane basins.

  2. South China connected to north India in Gondwana: sedimentary basin and detrital provenance analyses

    Science.gov (United States)

    Yao, W.; Li, Z. X.; Li, W. X.; Li, X. H.; Yang, J. H.

    2015-12-01

    The paleoposition of South China during the Ediacaran-Silurian is important for understanding the assembly of Gondwana. We report here the tectonostratigraphic evolution of the Ediacaran-Silurian Nanhua foreland basin in South China, and discuss South China's connection with Gondwana and potential tectonic triggers for both the Wuyi-Yunkai orogeny in South China and the Bhimphedian orogeny in north India. The Nanhua basin was involved in a three-stage evolution, which are: Stage 1 (the Ediacaran-Cambrian) recording the start of tectonic subsidence with turbiditic marine clastic deposition, fed by exotic orogens outboard South China; Stage 2 (the Ordovician to earliest-Silurian) featured by migrating depocentres with dominant shallow marine to deltaic clastic deposition, fed by the local Wuyi-Yunkai orogen; and Stage 3 (the Silurian) showing the arrival of depocentre in the Yangtze Block during the waning stage of the Wuyi-Yunkai orogeny with deltaic deposition in the remanent foreland basin. Detrital zircon analyses of the Ediacaran-Silurian sandstones across the Nanhua basin reveal a prominent age population of 1100-900 Ma (with a peak age at ~980 Ma) and moderate populations of Archean-Paleozoic ages, grossly matching that of crystalline and sedimentary rocks in northern India. Zircon isotopes of the Stage 1 samples suggest three Precambrian episodes of juvenile crustal growth at 3.0 Ga, 2.5 Ga and 1.0 Ga, and a major crustal reworking at 580-500 Ma for the source areas, which are constraint to be northwestern India and its surrounding orogens. Together with other evidence, we propose that South China likely collided with northwestern India during the Gondwana assembly, generated the Bhimphedian orogeny in north India and formed two foreland basins on both the north India and South China sides. Far-field stress of the collision triggered the Ordovician-Silurian Wuyi-Yunkai orogeny in South China. The Stage 2-3 samples in the Nanhua basin of South China were shed

  3. Clinoptilolite zeolitized tuff from Central Alborz Range, North Iran

    Science.gov (United States)

    Taghipour, Batoul

    2010-05-01

    Zeolites are hydrated alumino-silicates of the alkaline and alkaline earth cations, principally sodium, potassium, calcium, and magnesium (Iijima 1980; Hay 1981). Zeolites occur principally in unmetamorphosed sedimentary rocks and are particularly widespread in volcani-clastic strata (Hay, 1978). Clinoptilolite is a natural zeolite of the heulandite group with the simplified formula of (Na, K)6 Si30 Al6 O72 .nH2. It is the most common natural zeolite found mainly in sedimentary rocks of volcanic origin. Alborz zone is one of the important geological divisions in Iran. This zone is restricted to Kopeh dagh zone in North & Central Iranian zone in South and is a region of active deformation within the broad Arabian-Eurasia collision zone (Allen et al. 2003). The zeolitized green tuff belt from Central Alborz which introduce here are made of volcanoclastic sequence of Karaj Formation. This belt is about 40 km long along Alborz Range and is Eocene in age. Zeolites and associated minerals of this altered vitric tuff studied. Zeolitization took place in some beds of Karaj Formations, with average range of 3 to 300 meters thickness. There are several gypsum lenses which interbed with a widespread green tuff succession in the studied area. On the basis of chemical composition these tuffs are in the range of acid to intermediate volcanic rocks. Also magmatic affinity is calc-alkaline and geological setting of the area belongs to volcanic arc granitoid. Petrographic data has shown that various shape and size of shard glass are the main component of tuffs. Based on the field studies, detail microscopy, XRD and electron microprobe analysis (EMPA), the following main minerals are determined: Clinoptilolite+montmorillonite+crystobalite. Clinoptilolite and smectite are predominant minerals in all altered samples. Concerning the Si/Al ratio of 40 point analyses of glass shards the Alborz tuff has clinoptilolite composition. Otherwise the chemical composition of altered shard glass

  4. Some new observations on the intra-plate deformation in the Central Indian Basin (CIB)

    Digital Repository Service at National Institute of Oceanography (India)

    Murthy, K.S.R.; Neprochnov, O.V.; Levchenko, O.V.; Rao, T.C.S.; Milanovsky, V.E.; Lakshminarayana, S.

    ) 185-193 185 Elsevier Science Publishers B.V., Amsterdam Some new observations on the intra-plate deformation in the Central Indian Basin (CIB) K.S.R. Murthy a, Yu.P. Neprochnov b, O.V. Levchenko b, T.C.S. Rao a, V.E. Milanovsky b and S... accepted May 6, 1993) ABSTRACT Murthy, K.S.R., Neprochnov, Yu.P., Levchenko, O.V., Rao, T.C.S., Milanovsky, V.E. and Lakshminarayana, S., 1993. Some new observations on the intra-plate deformation in the Central Indian Basin (CIB). Mar. Geol., 114: 185...

  5. Active shortening and intermontane basin formation in the central Puna Plateau: Salar de Pocitos, NW Argentina (24°37'S, 67°03'W)

    Science.gov (United States)

    Strecker, Manfred; Bookhagen, Bodo; Freymark, Jessica; Pingel, Heiko; Alonso, Ricardo N.

    2015-04-01

    Similar to other Cenozoic orogenic plateaus, extensional tectonics associated with mafic volcanism typifies the Altiplano-Puna of the southern Central Andes, while the flanks of the plateau and adjacent foreland areas experience shortening. Extensional tectonism in the plateau region since the late Miocene has been explained with delamination of lithospheric mantle. However, new evidence for protracted basin-wide shortening in the Salar de Pocitos region in the south-central Puna documents that the kinematic changeover from shortening to extension is highly diachronous. In this study we assess the deformation and geomorphic history of the Salar de Pocitos region using DGPS surveys, CRN dating of deformed pediment surfaces, and U/Pb dating of volcanic ash horizons in deformed strata. With average elevations of about 3.7 km the Altiplano-Puna is a first-order morphotectonic province of the southern central Andes and constitutes the world's second largest orogenic plateau. With few exceptions the Andean plateau consists of internally drained, partly coalesced sedimentary basins that are mainly bordered by reverse-fault bounded ranges, 5 to 6 km high. While there are many unifying plateau characteristics in the Altiplano (north) and Puna (south), including internal drainage, semi-arid to arid climate and associated deposition of evaporites, there are notable differences between both plateau sectors. In contrast to the vast Altiplano basin of Bolivia, the Argentine Puna comprises numerous, smaller and partly coalesced basins that reflect continued comparmentalization by the combined effects of tectonism and volcanic activity. The N-S oriented Salar de Pocitos basin is the vestige of a formerly contiguous sedimentary basin within the Puna interior. Unlike many other basins in this region it is bordered by the limb of an anticline developed in Tertiary sedimentary rocks on the west, while the eastern border is a reverse-faulted range front. To the north and south the

  6. Temperature and zooplankton size structure: climate control and basin-scale comparison in the North Pacific.

    Science.gov (United States)

    Chiba, Sanae; Batten, Sonia D; Yoshiki, Tomoko; Sasaki, Yuka; Sasaoka, Kosei; Sugisaki, Hiroya; Ichikawa, Tadafumi

    2015-02-01

    The global distribution of zooplankton community structure is known to follow latitudinal temperature gradients: larger species in cooler, higher latitudinal regions. However, interspecific relationships between temperature and size in zooplankton communities have not been fully examined in terms of temporal variation. To re-examine the relationship on a temporal scale and the effects of climate control thereon, we investigated the variation in copepod size structure in the eastern and western subarctic North Pacific in 2000-2011. This report presents the first basin-scale comparison of zooplankton community changes in the North Pacific based on a fully standardized data set obtained from the Continuous Plankton Recorder (CPR) survey. We found an increase in copepod community size (CCS) after 2006-2007 in the both regions because of the increased dominance of large cold-water species. Sea surface temperature varied in an east-west dipole manner, showing the typical Pacific Decadal Oscillation pattern: cooling in the east and warming in the west after 2006-2007. The observed positive correlation between CCS and sea surface temperature in the western North Pacific was inconsistent with the conventional interspecific temperature-size relationship. We explained this discrepancy by the geographical shift of the upper boundary of the thermal niche, the 9°C isotherm, of large cold-water species. In the eastern North Pacific, the boundary stretched northeast, to cover a large part of the sampling area after 2006-2007. In contrast, in the western North Pacific, the isotherm location hardly changed and the sampling area remained within its thermal niche throughout the study period, despite the warming that occurred. Our study suggests that while a climate-induced basin-scale cool-warm cycle can alter copepod community size and might subsequently impact the functions of the marine ecosystem in the North Pacific, the interspecific temperature-size relationship is not

  7. Literature and information related to the natural resources of the North Aleutian Basin of Alaska.

    Energy Technology Data Exchange (ETDEWEB)

    Stull, E.A.; Hlohowskyj, I.; LaGory, K. E.; Environmental Science Division

    2008-01-31

    The North Aleutian Basin Planning Area of the Minerals Management Service (MMS) is a large geographic area with significant natural resources. The Basin includes most of the southeastern part of the Bering Sea Outer Continental Shelf, including all of Bristol Bay. The area supports important habitat for a wide variety of species and globally significant habitat for birds and marine mammals, including several federally listed species. Villages and communities of the Alaska Peninsula and other areas bordering or near the Basin rely on its natural resources (especially commercial and subsistence fishing) for much of their sustenance and livelihood. The offshore area of the North Aleutian Basin is considered to have important hydrocarbon reserves, especially natural gas. In 2006, the MMS released a draft proposed program, 'Outer Continental Shelf Oil and Gas Leasing Program, 2007-2012' and an accompanying draft programmatic environmental impact statement (EIS). The draft proposed program identified two lease sales proposed in the North Aleutian Basin in 2010 and 2012, subject to restrictions. The area proposed for leasing in the Basin was restricted to the Sale 92 Area in the southwestern portion. Additional EISs will be needed to evaluate the potential effects of specific lease actions, exploration activities, and development and production plans in the Basin. A full range of updated multidisciplinary scientific information will be needed to address oceanography, fate and effects of oil spills, marine ecosystems, fish, fisheries, birds, marine mammals, socioeconomics, and subsistence in the Basin. Scientific staff at Argonne National Laboratory were contracted to assist MMS with identifying and prioritizing information needs related to potential future oil and gas leasing and development activities in the North Aleutian Basin. Argonne focused on three related tasks: (1) identify and gather relevant literature published since 1996, (2) synthesize and

  8. Hydrological Modeling of Highly Glacierized Basins (Andes, Alps, and Central Asia

    Directory of Open Access Journals (Sweden)

    Nina Omani

    2017-02-01

    Full Text Available The Soil and Water Assessment Tool (SWAT was used to simulate five glacierized river basins that are global in coverage and vary in climate. The river basins included the Narayani (Nepal, Vakhsh (Central Asia, Rhone (Switzerland, Mendoza (Central Andes, Argentina, and Central Dry Andes (Chile, with a total area of 85,000 km2. A modified SWAT snow algorithm was applied in order to consider spatial variation of associated snowmelt/accumulation by elevation band across each subbasin. In previous studies, melt rates varied as a function of elevation because of an air temperature gradient while the snow parameters were constant throughout the entire basin. A major improvement of the new snow algorithm is the separation of the glaciers from seasonal snow based on their characteristics. Two SWAT snow algorithms were evaluated in simulation of monthly runoff from the glaciered watersheds: (1 the snow parameters are lumped (constant throughout the entire basin and (2 the snow parameters are spatially variable based on elevation bands of a subbasin (modified snow algorithm. Applying the distributed SWAT snow algorithm improved the model performance in simulation of monthly runoff with snow-glacial regime, so that mean RSR decreased to 0.49 from 0.55 and NSE increased to 0.75 from 0.69. Improvement of model performance was negligible in simulations of monthly runoff from the basins with a monsoon runoff regime.

  9. Comparative Study of Basins within Palaeogene Seaway in East China and Cretaceous Seaway in North America and Its Reservoir Significance

    Institute of Scientific and Technical Information of China (English)

    Wu Xiantao

    2007-01-01

    The well known Cretaceous seaway in North America was recognized in the middle of the last century and the Palaeogene seaway in East China was proposed by the author recently. The two seaways located on the opposite sides of North Pacific Ocean may be not a coincidence,and a comparative study was made in this paper. The results show that the two seaways inundated basins share several similarities particularly in basin origin,filling processes and reservoir facies. It is suggested that reservoir facies of estuarine sandstone and shelf bar sandstone related to sea level fluctuation,which are well developed in the Cretaceous seaway covered basins in North America might have been also developed here in Palaeogene seaway inundated basins in East China. Therefore it is worth paying more attention to finding these new reservoir facies on this side of the Pacific ocean. Evidences of sedimentology and ichnology indicate that good prospects are likely.

  10. The paleomagnetism and geological significance of Meso- proterozoic dyke swarms in the central North China Craton

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Mesoproterozoic mafic dyke swarms are extensively distributedin the central North China Craton(NCC) including North Shanxi, Wutai and Lüliang areas, which are not deformed and metamorphic but high magnetic, so the dyke swarms become the mark to compare the high meta-morphic rock areas in magnetism. Based on the analysis of paleomagnetism of mafic dyke swarms in North Shanxi, Wutai and Lüliang areas, NCC inclined southward about 18° so that North Shanxi lifted up and rotated 10° left to Wutai area. The dyke swarms in Lüliang developed later than in North Shanxi and Wutai area. The NNW-trending and WNW-trending dyke swarms developed in Lüliang while the North China Plate moved northward consistently so that the paleomagnetism of dyke swarms in Lüliang is greatly different from North Shanxi and Wutai area.

  11. Recovery of deep-sea meiofauna after artificial disturbance in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Ingole, B.S.; Goltekar, N.R.; Gonsalves, S.; Ansari, Z.A.

    -1 1 Recovery of Deep-sea Meiofauna after Artificial Disturbance in the Central Indian Basin INGOLE B.S*., R. GOLTEKAR, S. GONSALVES and Z. A. ANSARI Biological Oceanography Division, National Institute of Oceanography, Dona Paula, Goa; 403004... in the Central Indian Ocean under the Indian Deep- sea Environmental Experiment (INDEX). The seafloor bottom was physically disturbed by moving a benthic disturber in a 3000 m long x 200 m wide area. 3 Sharma (2001) described the location and characteristics...

  12. Assessing and addressing the re-eutrophication of Lake Erie: central basin hypoxia

    Science.gov (United States)

    Scavia, Donald; Allan, J. David; Arend, Kristin K.; Bartell, Steven; Beletsky, Dmitry; Bosch, Nate S.; Brandt, Stephen B.; Briland, Ruth D.; Daloğlu, Irem; DePinto, Joseph V.; Dolan, David M.; Evans, Mary Anne; Farmer, Troy M.; Goto, Daisuke; Han, Haejin; Höök, Tomas O.; Knight, Roger; Ludsin, Stuart A.; Mason, Doran; Michalak, Anna M.; Richards, R. Peter; Roberts, James J.; Rucinski, Daniel K.; Rutherford, Edward; Schwab, David J.; Sesterhenn, Timothy M.; Zhang, Hongyan; Zhou, Yuntao

    2014-01-01

    Relieving phosphorus loading is a key management tool for controlling Lake Erie eutrophication. During the 1960s and 1970s, increased phosphorus inputs degraded water quality and reduced central basin hypolimnetic oxygen levels which, in turn, eliminated thermal habitat vital to cold-water organisms and contributed to the extirpation of important benthic macroinvertebrate prey species for fishes. In response to load reductions initiated in 1972, Lake Erie responded quickly with reduced water-column phosphorus concentrations, phytoplankton biomass, and bottom-water hypoxia (dissolved oxygen 2) requires cutting total phosphorus loads by 46% from the 2003–2011 average or reducing dissolved reactive phosphorus loads by 78% from the 2005–2011 average. Reductions to these levels are also protective of fish habitat. We provide potential approaches for achieving those new loading targets, and suggest that recent load reduction recommendations focused on western basin cyanobacteria blooms may not be sufficient to reduce central basin hypoxia to 2000 km2.

  13. Seasonality of Groundwater Recharge in the Basin and Range Province, Western North America

    Science.gov (United States)

    Neff, K.; Meixner, T.; De La Cruz, L.

    2014-12-01

    Groundwater recharge is the primary source of aquifer replenishment, an important source of freshwater for human consumption and riparian area sustainability in semi-arid regions. It is critical to understand the current groundwater recharge regimes in groundwater basins throughout the Western U.S. and how those regimes might shift in the face of climate change, land use change and management manipulations that impact the availability and composition of groundwater resources. Watersheds in the Basin and Range Province are characterized by a variable precipitation regime of wet winters, and variable summer precipitation. The horst-graben structure of these basins lends itself to orographic and continental precipitation effects that make mountain block and mountain front recharge critical components of annual recharge. The current assumption is that the relative contributions to groundwater recharge by summer and winter precipitation vary throughout the province, with winter precipitation dominating in the northern parts of the region, and summer monsoonal precipitation playing a more significant role in the south, where the North American Monsoon extends its influence. To test this hypothesis, stable water isotope data of groundwater and precipitation from sites in Sonora, Mexico and the U.S. states of California, Nevada, Utah, Arizona, Colorado, New Mexico, and Texas were examined to characterize and compare groundwater recharge regimes throughout the region. Preliminary stable water isotope results from the southernmost Rio San Miguel Basin in Sonora, Mexico indicate that groundwater is composed of 64%±14% summer monsoon precipitation, in contrast to more northern basins where winter precipitation is the source of 79-90% of basin groundwater.

  14. Project plan-Surficial geologic mapping and hydrogeologic framework studies in the Greater Platte River Basins (Central Great Plains) in support of ecosystem and climate change research

    Science.gov (United States)

    Berry, Margaret E.; Lundstrom, Scott C.; Slate, Janet L.; Muhs, Daniel R.; Sawyer, David A.; VanSistine, D. Paco

    2011-01-01

    The Greater Platte River Basin area spans a central part of the Midcontinent and Great Plains from the Rocky Mountains on the west to the Missouri River on the east, and is defined to include drainage areas of the Platte, Niobrara, and Republican Rivers, the Rainwater Basin, and other adjoining areas overlying the northern High Plains aquifer. The Greater Platte River Basin contains abundant surficial deposits that were sensitive to, or are reflective of, the climate under which they formed: deposits from multiple glaciations in the mountain headwaters of the North and South Platte Rivers and from continental ice sheets in eastern Nebraska; fluvial terraces (ranging from Tertiary to Holocene in age) along the rivers and streams; vast areas of eolian sand in the Nebraska Sand Hills and other dune fields (recording multiple episodes of dune activity); thick sequences of windblown silt (loess); and sediment deposited in numerous lakes and wetlands. In addition, the Greater Platte River Basin overlies and contributes surface water to the High Plains aquifer, a nationally important groundwater system that underlies parts of eight states and sustains one of the major agricultural areas of the United States. The area also provides critical nesting habitat for birds such as plovers and terns, and roosting habitat for cranes and other migratory birds that travel through the Central Flyway of North America. This broad area, containing fragile ecosystems that could be further threatened by changes in climate and land use, has been identified by the USGS and the University of Nebraska-Lincoln as a region where intensive collaborative research could lead to a better understanding of climate change and what might be done to adapt to or mitigate its adverse effects to ecosystems and to humans. The need for robust data on the geologic framework of ecosystems in the Greater Platte River Basin has been acknowledged in proceedings from the 2008 Climate Change Workshop and in draft

  15. Middle Miocene chitons (Polyplacophora from the Slovak part of the Vienna Basin and the Danube Basin (Central Paratethys

    Directory of Open Access Journals (Sweden)

    Ruman Andrej

    2015-12-01

    Full Text Available We describe species-rich chiton assemblages from the Middle Miocene of the Slovak part of the Vienna Basin and the Danube Basin (Central Paratethys. They were found at five localities, including Devínska Nová Ves brickyard, Devínska Nová Ves-Útočnica, Rohožník clay pit, Kúty-45 borehole and Dubová. Thirteen species belong to eight genera from the families Leptochitonidae, Hanleyidae, Callochitonidae, Chitonidae, Tonicellidae and Acanthochitonidae. They occur predominantly in redeposited, moderately-sorted rhodolith-rich or well-sorted bioclastic layers of the Late Badenian age, and belong to lineages that presently inhabit warm-temperate and tropical regions.

  16. Slope angle studies from multibeam sonar data on three seamounts in Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Kodagali, V.N.

    is presented here. The slope angle grid can be used to create the slope angle map. Morphology of three seamounts from Central Indian Basin and the slope angle data on them are described. The seamounts are of the heights 1000-1200 m and occupy area up to 300 sq...

  17. Distribution of baroduric, psychrotrophic and culturable nitrifying and denitrifying bacteria in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.; PradeepRam, A.S.; Nair, S.; Nath, B.N.; Chandramohan, D.

    The abundance of baroduric, culturable nitrifying and denitrifying bacteria in the deep-sea cores of Central Indian Basin (CIB) at ca 5000 m depth was investigated. Analysis of 8 cores, sampled between 10 degrees 00 minutes S and 75 degrees 55...

  18. Magnetic lineations, fracture zones and seamounts in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    KameshRaju, K.A.

    Magnetic and bathymetric data collected in the Central Indian Basin, between 8 degrees S and 16 degrees S lat., and 71 degrees E and 82 degrees E long. have been studied. The inferred fracture zones at 73 degrees E, 76 degrees 30'E and 79 degrees E...

  19. Multibeam bathymetric, gravity and magnetic studies over 79 degrees E fracture zone, central Indian basin

    Digital Repository Service at National Institute of Oceanography (India)

    KameshRaju, K.A.; Ramprasad, T.; Kodagali, V.N.; Nair, R.R.

    A regional scale bathymetric map has been constructed for the 79 degrees E fracture zone (FZ) in the Central Indian Basin between 10 degrees 15'S and 14 degrees 45'S lat. and 78 degrees 55'E and 79 degrees 20'E long. using the high...

  20. Sedimentology and paleogeography of an Upper Cretaceous turbidite basin in the South-Central Pyrenees, Spain

    NARCIS (Netherlands)

    Hoorn, van B.

    1970-01-01

    The present study deals with the primary lithology, sedimentary structures, depositional history and paleogeography of an Upper Cretaceous turbidite basin in the south-central Pyrenees, and presents a brief review of the lithology and depositional environment of surrounding contemporaneous deposits.

  1. Rare earth element distribution and behaviour in buried manganese nodules from the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Banakar, V.K.

    Eight burried manganese nodules taken in the upper metre of a siliceous ooze sediment core in the Central Indian Basin at 14 degrees S and 74 degrees E were analysed for major, trace and rare earth (REE) elements. Interelemental correlation yields a...

  2. Response of sedimentary nucleic acids to benthic disturbance in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, C.E.G.; DeSouza, M.J.B.D.; Nair, S.; LokaBharathi, P.A.

    Information on the response of nucleic acids (i.e., DNA and RNA) to simulated benthic disturbance was obtained from samples collected from eight sediment cores (0-10 cm) located in the Central Indian Basin (CIB). In general the total sedimentary DNA...

  3. Deposition of Mn-Cu-Ni-enriched sediments during glacial period in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Borole, D.V.

    Two siliceous sediment cores collected from the Central Indian Basin have been analysed for organic carbon, biogenic silica, Al, Mn, Ni and Cu content. The concentrations of Mn, Cu and Ni showed one order of magnitude variation (an enrichment by a...

  4. Geological evolution, regional perspectives and hydrocarbon potential of the northwest Phu Khanh Basin, offshore Central Vietnam

    DEFF Research Database (Denmark)

    Fyhn, Michael Bryld Wessel; Nielsen, Lars H.; Boldreel, Lars Ole;

    2009-01-01

    and subsidence rates increased after the Middle Miocene times due to eastward tilting of Central Vietnam and the adjacent offshore area. Potential direct hydrocarbon indicators (DHIs) in the Phu Khanh Basin include common amplitude anomalies, gas chimney-like features and seafloor gas seeps. In addition, oil...

  5. Early Cretaceous decapod Crustacea from the Neuquén Basin, west-central Argentina

    NARCIS (Netherlands)

    Aguirre-Urreta, Maria Beatriz

    2003-01-01

    Marine deposits of the Neuquén Basin of west-central Argentina (southern South America) are richly fossiliferous; its Mesozoic invertebrate faunas, represented mostly by molluscs, have been extensively studied since the nineteenth century. However, Early Cretaceous decapod crustaceans are far less k

  6. Multiple ash layers in late Quaternary sediments from the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Mascarenhas-Pereira, M.B.L.; Nath, B.N.; Iyer, S.D.; Borole, D.V.; Parthiban, G.; Jijin, R.; Khedekar, V.D.

    We have investigated three sediment cores collected from water depths > 5000 m along the transect 76°30`E in close proximity to a fracture zone in the Central Indian Basin (CIB). The cores yielded five volcanic horizons of which four have visual...

  7. Hydrovolcanic activity in the Central Indian Ocean Basin. Does nature mimic laboratory experiments?

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; ShyamPrasad, M.; Gupta, S.M.; Charan, S.N; Mukherjee, A

    enigmatic and indeterminate. We present here the finding of volcanic magnetite spherules up to 475 mu m in diameter which were recovered from the base of a seamount (basement age approx 50 Ma) in the Central Indian Ocean Basin (CIOB). The spherules have...

  8. Assessment of shale-oil resources of the Central Sumatra Basin, Indonesia, 2015

    Science.gov (United States)

    Schenk, Christopher J.; Charpentier, Ronald R.; Klett, Timothy R.; Tennyson, Marilyn E.; Mercier, Tracey J.; Brownfield, Michael E.; Pitman, Janet K.; Gaswirth, Stephanie B.; Leathers-Miller, Heidi M.

    2015-11-12

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated means of 459 million barrels of shale oil, 275 billion cubic feet of associated gas, and 23 million barrels of natural gas liquids in the Central Sumatra Basin, Indonesia.

  9. Current structure and kinetic energy of the abyssal waters in the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, V.S.N.; RameshBabu, V.; Suryanarayana, A.; Beena, B.S.

    Analysis of abyssal currents measured at 7 levels viz., 4, 8, 15, 30, 50, 100 and 500 mab during October 1996-April 1997 at 10 degrees 01'S, 76 degrees E in the Benthic Disturbance Experiment Site (BDES) in the Central Indian Ocean Basin...

  10. Petrological Characteristics and Genesis of the Central Indian Ocean Basin Basalts

    Digital Repository Service at National Institute of Oceanography (India)

    Das, P.; Iyer, S.D.; Hazra, S.

    The Central Indian Ocean Basin (CIOB) basalts are plagioclase-rich, while olivine and pyroxene are very few. The analyses of 41 samples reveal high FeO sup(T) (approx. 10-18 wt percent) and TiO sub(2) (approx. 1.4-2.7 wt percent) indicating a...

  11. Middle Ordovician brachiopods from the Stairway Sandstone, Amadeus Basin, central Australia

    DEFF Research Database (Denmark)

    Jakobsen, Kristian Grube; Brock, Glenn A.; Nielsen, Arne Thorshøj;

    2014-01-01

    Middle Ordovician brachiopod faunas from the Amadeus Basin, central Australia are poorly known. The Darriwilian Stairway Sandstone was sampled stratigraphically for macrofossils in order to provide new information on marine benthic diversity in this clastic-dominated, shallow-water palaeoenvironm...

  12. Mineral deposit formation in Phanerozoic sedimentary basins of north-east Africa: the contribution of weathering

    Science.gov (United States)

    Germann, Klaus; Schwarz, Torsten; Wipki, Mario

    1994-12-01

    The intra- and epicontinental basins in north-east Africa (Egypt, Sudan) bear ample evidence of weathering processes repeatedly having contributed to the formation of mineral deposits throughout the Phanerozoic. The relict primary weathering mantle of Pan-African basement rocks consists of kaolinitic saprolite, laterite (in places bauxitic) and iron oxide crust. On the continent, the reaccumulation of eroded weathering-derived clay minerals (mainly kaolinite) occurred predominantly in fluvio-lacustrine environments, and floodplain and coastal plain deposits. Iron oxides, delivered from ferricretes, accumulated as oolitic ironstones in continental and marine sediments. Elements leached from weathering profiles accumulated in continental basins forming silcrete and alunite or in the marine environment contributing to the formation of attapulgite/saprolite and phosphorites. The Early Paleozoic Tawiga bauxitic laterite of northern Sudan gives a unique testimony of high latitude lateritic weathering under global greenhouse conditions. It formed in close spatial and temporal vicinity to the Late Ordovician glaciation in north Africa. The record of weathering products is essentially complete for the Late Cretaceous/Early Tertiary. From the continental sources in the south to the marine sinks in the north, an almost complete line of lateritic and laterite-derived deposits of bauxitic kaolin, kaolin, iron oxides and phosphates is well documented.

  13. Petrographically deduced triassic climate for the Deep River Basin, eastern piedmont of North Carolina

    Energy Technology Data Exchange (ETDEWEB)

    McCarn, S.T.; Mansfield, C.F.

    1985-01-01

    A petrographic comparison of Triassic, fluvial sandstones from the Deep River Basin in the eastern piedmont of North Carolina with nearby Holocene stream sands (1) indicates that he Triassic climate was more arid than today's and (2) distinguishes an eastern, more plutonic terrane from a western, more metamorphic source terrane. The paleoclimatic interpretation is based on differences in framework composition between modern and ancient sands of the same grain size, derived from the same rock type, transported similar distances and deposited in similar settings. The Triassic sandstones contain more lithic-fragments but less quartz than otherwise equivalent, modern sand in the Deep River Basin. Feldspar content is more complex, controlled by both source-rock composition and climate. Sand from the more plutonic terrane contains more feldspar and plutonic lithic-fragments than sand from the more metamorphic terrane, which contains more quartz and metamorphic lithic-fragments. This petrographic interpretation of the Triassic sandstones along with the presence of coal, limestone, chert and caliche in the middle of the section suggests that the Triassic climate was cyclic, changing from arid to humid and back to arid. Plate-tectonic reconstructions place the Deep River Basin between the Triassic equator and Tropic of cancer, where the easterly trade winds would predominate. Therefore, the arid portions of the cycle could have been due to a periodic, orographic, rain shadow formed as the result of intermittent movement along the Jonesboro Fault, creating a highland area east of the Deep River Basin.

  14. Aerosol optical depth over central north Asia based on MODIS-Aqua data

    Science.gov (United States)

    Avgousta Foutsi, Athina; Korras Carraca, Marios Bruno; Matsoukas, Christos; Biskos, George

    2016-04-01

    Atmospheric aerosols, both natural and anthropogenic, can affect the regional and global climate through their direct, indirect, and semi-direct effects on the radiative energy budget of the Earth-atmosphere system. To quantify these effects it is important to determine the aerosol load, and an effective way to do that is by measuring the aerosol optical depth (AOD). The central Asia region (mainly the Caspian and Aral sea basins), the arid and semi-arid regions of Western China as well as Siberia are of great interest due to the significant natural sources of mineral aerosols originating from local deserts and biomass burning from wildfires in boreal forests. What is of particular interest in the region is the phenomenal shrinking and desertification of the Aral Sea that drives an intense salt and dust transport from the exposed sea-bed to the surrounding regions with important implications in regional air quality. Anthropogenic particles are also observed due to fossil-fuel combustion occurring mainly at oil refineries in the Caspian Sea basin. Here we investigate the spatial and temporal variability of the AOD at 550 nm over central Asia, Siberia and western China, in the region located between 35° N - 65° N and 45° E - 110° E. For our analysis we use Level-3 daily MODIS - Aqua Dark Target - Deep Blue combined product, from the latest collection (006), available in a 1°×1° resolution (ca. 100 km × 100 km) over the period 2002-2014. Our results indicate a significant spatial variability of the aerosol load over the study region. The highest AODs are observed over the Aral Sea year-round, with extreme values reaching 2.1 during July. In the rest of our study region a clear seasonal cycle with highest AOD values (up to 1.2 over the Taklamakan Desert) during spring and summer is observed. The arid parts of central north Asia are characterized by larger aerosol loads during spring, lower but still high AOD in summer and much lower values in autumn and spring

  15. Micropaleontologic record of Quaternary paleoenvironments in the Central Albemarle Embayment, North Carolina, U.S.A.

    Science.gov (United States)

    Culver, Stephen J.; Farrell, Kathleen M.; Mallinson, David J.; Willard, Debra A.; Horton, Benjamin P.; Riggs, Stanley R.; Thieler, E. Robert; Wehmiller, John F.; Parham, Peter; Snyder, Scott W.; Hillier, Caroline

    2011-01-01

    To understand the temporal and spatial variation of eustatic sea-level fluctuations, glacio-hydro-isostacy, tectonics, subsidence, geologic environments and sedimentation patterns for the Quaternary of a passive continental margin, a nearly complete stratigraphic record that is fully integrated with a three dimensional chronostratigraphic framework, and paleoenvironmental information are necessary. The Albemarle Embayment, a Cenozoic regional depositional basin in eastern North Carolina located on the southeast Atlantic coast of the USA, is an ideal setting to unravel these dynamic, interrelated processes.Micropaleontological data, coupled with sedimentologic, chronostratigraphic and seismic data provide the bases for detailed interpretations of paleoenvironmental evolution and paleoclimates in the 90. m thick Quaternary record of the Albemarle Embayment. The data presented here come from a transect of cores drilled through a barrier island complex in the central Albemarle Embayment. This area sits in a ramp-like setting between late Pleistocene incised valleys.The data document the episodic infilling of the Albemarle Embayment throughout the Quaternary as a series of transgressive-regressive (T-R) cycles, characterized by inner shelf, midshelf, and shoreface assemblages, that overlie remnants of fluvial to estuarine valley-fill. Barrier island and marginal marine deposits have a low preservation potential. Inner to mid-shelf deposits of the early Pleistocene are overlain by similar middle Pleistocene shelf sediments in the south of the study area but entirely by inner shelf deposits in the north. Late Pleistocene marine sediments are of inner shelf origin and Holocene deposits are marginal marine in nature. Pleistocene marine sediments are incised, particularly in the northern half of the embayment by lowstand paleovalleys, partly filled by fluvial/floodplain deposits and in some cases, overlain by remnants of transgressive estuarine sediments. The shallowing

  16. Assessment of the sardine (Sardina pilchardus Walbaum, 1792 fishery in the eastern Mediterranean basin (North Aegean Sea

    Directory of Open Access Journals (Sweden)

    K. ANTONAKAKIS

    2012-12-01

    Full Text Available The aim of this study was to describe the biometric characteristics of the European sardine (Sardina pilchardus catches and assess the current status of sardine stock in North Aegean Sea based on population characteristics and abundance trends. The stock was dominated by age groups 1 and 2, not exceeding age group 4. The sardine stock in this area was assessed through an Integrated Catch-at-Age model which implements a separable Virtual Population Analysis on catch at age data with weighted tuning indices. Sardine landings data derived from the commercial purse seine fishery over the period 2000-2008 were combined with the age structure of the stock as resulted from fisheries independent acoustic surveys. Sensitivity analysis of the impact of natural mortality values on stock assessment results was applied. Additionally forecast of the sardine population parameters and catches under different exploitation scenarios was implemented in a medium term basis. Results indicated that the North Aegean Sea sardine stock is considered fully exploited with the fishery operating close but over the empirical exploitation level for sustainability. Finally, the status of the sardine stock in N. Aegean Sea is discussed in relation to the sardine stocks from the western and the central Mediterranean basin.

  17. Macrofaunal diversity in the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pavithran, S.; Ingole, B.S.; Nanajkar, M.; Nath, B.N.

    . For example, offshore oil and gas reserves now constitute a major portion of overall energy sources (IEA 1996); increasing demand for metals has turned global attention towards the deep-sea polymetallic nodules. Nodules occur in all oceans, including... study, which attempts to identify macrofauna up to the family/genus/species level in the Central Indian Ocean. This documentation of the deep-sea biodiversity will be useful in understanding the global species distribution and their role in different...

  18. Subsidence History of the Eastern Depression in the North Yellow Sea Basin

    Institute of Scientific and Technical Information of China (English)

    CAO Dai-yong; WANG Xin-guo; ZHAN Wen-feng; LI Wen-yong

    2007-01-01

    Using a back-stripping method, our paper simulated the subsidence history of the eastern depression in the North Yellow Sea Basin. The subsidence history curve pattern and the subsidence chorisogram during every subsiding period were exposed. Combining with the regional geologic background and the distribution features of the subsiding centers in every period, a contrasting study of the pattern and the classical subsidence history curves shows the subsidence history is made up of Mesozoic (J3-K1) and Cenozoic (E2-Q) subsiding cycles. The two subsiding cycles are separated by the late Cretaceous and Paleocene (K2-E1) uplift denudation. Both subsiding cycles have the characteristics of an extension basin. The rapid subsidence during the late Jurassic and Eocene is equivalent to the initial subsiding phases in both cycles.. The slow subsidence of both, the early Cretaceous and Neogene, can be regarded as thermal subsidence phases.

  19. Morphotectonics of the Jamini River basin, Bundelkhand Craton, Central India; using remote sensing and GIS technique

    Science.gov (United States)

    Prakash, K.; Mohanty, T.; Pati, J. K.; Singh, S.; Chaubey, K.

    2016-12-01

    Morphological and morphotectonic analyses have been used to obtain information that influence hydrographic basins, predominantly these are modifications of tectonic elements and the quantitative description of landforms. Discrimination of morphotectonic indices of active tectonics of the Jamini river basin consists the analyses of asymmetry factor, ruggedness number, basin relief, gradient, basin elongation ratio, drainage density analysis, and drainage pattern analysis, which have been completed for each drainage basin using remote sensing and GIS techniques. The Jamini river is one of the major tributaries of the Betwa river in central India. The Jamini river basin is divided into five subwatersheds viz. Jamrar, Onri, Sainam, Shahzad and Baragl subwatershed. The quantitative approach of watershed development of the Jamini river basin, and its four sixth (SW1-SW4) and one fifth (SW5) order subwatersheds, was carried out using Survey of India toposheets (parts of 54I, 54K, 54L, 54O, and 54P), Landsat 7 ETM+, ASTER (GDEM) data, and field data. The Jamini river has low bifurcation index which is a positive marker of tectonic imprint on the hydrographic network. The analyses show that the geomorphological progression of the study area was robustly influenced by tectonics. The analysis demonstrates to extensional tectonics system with the following alignments: NE-SW, NW-SE, NNE-SSW, ENE-WSW, E-W, and N-S. Three major trends are followed by lower order streams viz. NE-SW, NW-SE, and E-W directions which advocate that these tectonic trends were active at least up to the Late Pleistocene. The assessment of morphotectonic indices may be used to evaluate the control of active faults on the hydrographic system. The analysis points out westward tilting of the drainage basins with strong asymmetry in some reaches, marked elongation ratio of subwatersheds, and lower order streams having close alignment with lineaments (active faults). The study facilitated to considerate the

  20. Stratigraphic cross sections of the Niobrara interval of the Cody Shale and associated rocks in the Wind River Basin, central Wyoming

    Science.gov (United States)

    Finn, Thomas M.

    2017-02-07

    The Wind River Basin in Wyoming is one of many structural and sedimentary basins that formed in the Rocky Mountain foreland during the Laramide orogeny. The basin is nearly 200 miles long, 70 miles wide, and encompasses about 7,400 square miles in central Wyoming. The basin is bounded by the Washakie Range, Owl Creek uplift, and southern Bighorn Mountains on the north, the Casper arch on the east, the Granite Mountains on the south, and Wind River Range on the west.Many important conventional oil and gas fields producing from reservoirs ranging in age from Mississippian through Tertiary have been discovered in this basin. In addition, an extensive unconventional overpressured basin-centered gas accumulation has been identified in Cretaceous and Tertiary strata in the deeper parts of the basin. It has long been suggested that various Upper Cretaceous marine shales, including the Cody Shale, are the principal hydrocarbon source rocks for many of these accumulations. With recent advances and success in horizontal drilling and multistage fracture stimulation, there has been an increase in exploration and completion of wells in these marine shales in other Rocky Mountain Laramide basins that were traditionally thought of only as hydrocarbon source rocks.The two stratigraphic cross sections presented in this report were constructed as part of a project carried out by the U.S. Geological Survey to characterize and evaluate the undiscovered continuous (unconventional) oil and gas resources of the Niobrara interval of the Upper Cretaceous Cody Shale in the Wind River Basin in central Wyoming. The primary purpose of the cross sections is to show the stratigraphic relationship of the Niobrara equivalent strata and associated rocks in the lower part of the Cody Shale in the Wind River Basin. These two cross sections were constructed using borehole geophysical logs from 37 wells drilled for oil and gas exploration and production, and one surface section along East Sheep Creek

  1. Driving factors for runoff decline in the Upper Hanjiang basin, a major water source for the South-to-North Water Diversion Project in China

    OpenAIRE

    Zhang, S.; Yang, D.; Xu, X.

    2015-01-01

    With dramatic changes in climate and land-cover patterns around the world, it is of great significance to evaluate the corresponding influence on runoff change as water resources have become a strategic resource. We analysed the runoff change driven by landscape change and climate variation in Hanjiang River basin, which is the water source area of the central route of the South-to-North Water Diversion Project in China. Results show that the runoff decreased greatly from 1960 to 2012 in all ...

  2. Preliminary Results From the CAUGHT Experiment: Investigation of the North Central Andes Subsurface Using Receiver Functions and Ambient Noise Tomography

    Science.gov (United States)

    Ryan, J. C.; Ward, K. M.; Porter, R. C.; Beck, S. L.; Zandt, G.; Wagner, L. S.; Minaya, E.; Tavera, H.

    2011-12-01

    Jamie Ryan, Kevin M. Ward, Ryan Porter, Susan Beck, George Zandt, Lara Wagner, Estela Minaya, and Hernando Tavera The University of Arizona The University of North Carolina San Calixto Observatorio, La Paz, Bolivia IGP, Lima, Peru In order to investigate the interplay between crustal shortening, lithospheric removal, and surface uplift we have deployed 50 broadband seismometers in northwestern Bolivia and southern Peru as part of the interdisciplinary Central Andean Uplift and Geodynamics of High Topography (CAUGHT) project. The morphotectonic units of the central Andes from west to east, consist of the Western Cordillera, the active volcanic arc, the Altiplano, an internally drained basin (~4 km elevation), the Eastern Cordillera, the high peaks (~6 km elevation) of an older fold and thrust belt, the Subandean zone, the lower elevation active fold and thrust belt, and the foreland Beni basin. Between northwestern Bolivia and southern Peru, the Altiplano pinches out north of Lake Titicaca as the Andes narrow northward. The CAUGHT seismic instruments were deployed between 13° to 18° S latitudes to investigate the crust and mantle lithosphere of the central Andes in this transitional zone. In northwest Bolivia, perpendicular to the strike of the Andes, there is a total of 275 km of documented upper crustal shortening (15° to 17°S) (McQuarrie et al, 2008). Associated with the shortening is crustal thickening and possibly lithospheric removal as the thickening lithospheric root becomes unstable. An important first order study is to compare upper crustal shortening estimates with present day crustal thickness. To estimate crustal thickness, we have calculated receiver functions using an iterative deconvolution method and used common conversion point stacking along the same profile as the geologically based shortening estimates. In our preliminary results, we observed a strong P to S conversion corresponding to the Moho at approximately 60-65 km depth underneath the

  3. Finding the lost segment of the North Anatolian Fault in the Bursa Basin, Turkey

    Science.gov (United States)

    Kutoglu, S. H.; Deguchi, T.; Gundogdu, O.; Seker, D. Z.; Kuscu, S.

    2011-12-01

    After the 1999 Golcuk Mw=7.4, the seismic stress of the North Anatolian Fault has been transferred onto the segments in the Marmara Sea. The NAF is separated to three branches around the Marmara region; one branch runs into the Marmara Sea from the Yalova-Cinarcik location in the north, the second branch runs into the Marmara Sea from the Gemlik location in the south, and the last one goes toward the Bursa basin from the Sakarya-Pamukova location in the lower south. Some researchers consider that the south branch, which experienced the last major earthquake in the year 1064, poses a danger as much as the north branch.For that reason, this study has been conducted for monitoring the fault activities around the Bursa basin. In this respect, the four Palsar data having the best baseline condition have been obtained between the years 2007-2010. The processing of these data have been resulted in significant deformation interferograms for the data pairs of 31st Oct 2007-8th May 2010 and 31st Jan. 2008-24th Dec. 2010. There are seen deformation anomalies in the Bursa basin along 33 km long in E-W direction and 4.5 km long in N-S direction. The shape of the deformation fringes points out that there is a right lateral strike slip fault line passing through the Bursa basin. The geomorphologic characteristics in the region make us think this fault line may connect to the Sakarya-Geyve branch of the North Anatolian Fault system. The maximum amount of the deformation around the fault line has been determined 18 cm in three years. This amount is too much in comparison to 2.2 cm/yr slip rate of the NAF. As the deformation anomalies are investigated in detail a contraction draws attention, overlapping with a right lateral strike slip motion. Consequently, it can precociously be sad that there exits an uplifting combining with the lateral motion. In addition, significant deformation anomalies have been detected on the Gemlik location where the Iznik fault segment reaches the

  4. Central Wind Forecasting Programs in North America by Regional Transmission Organizations and Electric Utilities: Revised Edition

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, J.; Porter, K.

    2011-03-01

    The report and accompanying table addresses the implementation of central wind power forecasting by electric utilities and regional transmission organizations in North America. The first part of the table focuses on electric utilities and regional transmission organizations that have central wind power forecasting in place; the second part focuses on electric utilities and regional transmission organizations that plan to adopt central wind power forecasting in 2010. This is an update of the December 2009 report, NREL/SR-550-46763.

  5. Statistical Aspects of Tropical Cyclone Activity in the North Atlantic Basin, 1945-2010

    Science.gov (United States)

    Wilson, Robert M.

    2012-01-01

    Examined are statistical aspects of the 715 tropical cyclones that formed in the North Atlantic basin during the interval 1945-2010. These 715 tropical cyclones include 306 storms that attained only tropical storm strength, 409 hurricanes, 179 major or intense hurricanes, and 108 storms that struck the US coastline as hurricanes. Comparisons made using 10-year moving average (10-yma) values between tropical cyclone parametric values and surface air and ENSO-related parametric values indicate strong correlations to exist, in particular, against the Armagh Observatory (Northern Ireland) surface air temperature, the Atlantic Multi-decadal Oscillation (AMO) index, the Atlantic Meridional Mode (AMM) index, and the North Atlantic Oscillation (NAO) index, in addition to the Oceanic Ni o index (ONI) and Quasi-Biennial Oscillation (QBO) indices. Also examined are the decadal variations of the tropical cyclone parametric values and a look ahead towards the 2012 hurricane season and beyond.

  6. Is the extension of the Mexican Mesa Central (southern Basin & Range province) related to a gravitational collapse toward the Gulf of Mexico?

    Science.gov (United States)

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

    2009-04-01

    The middle to late Cenozoic extension that generated the Basin and Range province (western North America) is one of the most important tectonic events to affect the North American plate. The characteristics of this extension have been extensively studied, but its origin is equally extensively debated. Proposed origins can be broadly categorized into interplate mechanisms that focus on various interactions between the Pacific or Farallon and North American plates and intraplate mechanisms that interpret extension to result from the gravitational collapse of a previously overthickened crust. It is commonly admitted that the Basin and Range extension in western Mexico migrated from East to West toward the Gulf of California. Middle to late Miocene extension around the Gulf of California (Gulf Extensional Province) is commonly interpreted as resulting from partitioning of oblique Pacific-North American plate motion into strike-slip displacement along the margin and ENE extension perpendicular to the margin within the North American plate. It is generally assumed that this mechanism also applies to the kinematically similar, predominantly ENE extension that occurred at the same time throughout the southern Basin and Range province. However structural data we collected in the Mesa Central area, along the eastern part of the Mexican Basin and Range province, argue for a post-27My N130° extension toward the Gulf of Mexico that produced highly asymmetrical grabens, with a major motion along their western flanks. Our recent works, based on the interpretation of seismic profiles, also show that the late Oligocene to present deformation along the western margin of the Gulf of Mexico was generated by a crustal shortening. In spite of a low crustal thickness the Mesa Central is an uplifted plateau with a mean altitude of 1800m. This elevation of the Mesa Central is mainly due to the high thermal gradients that characterize the back arc domain. By contrast the crust of the Gulf

  7. Meso-Cenozoic Tectono-Thermal Evolution History in Bohai Bay Basin, North China

    Institute of Scientific and Technical Information of China (English)

    Yinhui Zuo; Nansheng Qiu; Jiawei Li; Qingqing Hao; Xiongqi Pang; Zhongying Zhao; Qi Zhu

    2015-01-01

    The thermal history of sedimentary basins is a key factor for hydrocarbon accumula-tion and resource assessment, and is critical in the exploration of lithospheric tectono-thermal evo-lution. In this paper, the Cenozoic thermal histories of nearly 200 wells and the Mesozoic thermal histories of 15 wells are modeled based on the vitrinite reflectance and apatite fission track data in Bohai Bay Basin, North China. The results show that the basin experienced Early Cretaceous and Paleogene heat flow peaks, which reveals two strong rift tectonic movements that occurred in the Cretaceous and the Paleogene in the basin, respectively. The thermal evolution history in Bohai Bay Basin can be divided into five stages including (1) the low and stable heat flow stage from the Trias-sic to the Jurassic, with the heat flow of 53 to 58 mW/m2;(2) the first heat flow peak from the Early Cretaceous to the middle of the Late Cretaceous, with a maximum heat flow of 81 to 87 mW/m2;(3) the first post-rift thermal subsidence stage from the middle of the Late Cretaceous to the Paleocene, with the heat flow of 65 to 74 mW/m2 at the end of the Cretaceous; (4) the second heat flow peak from the Eocene to the Oligocene, with a maximum heat flow of 81 to 88 mW/m2;and (5) the second thermal subsidence stage from the Neogene to present, with an average heat flow of 64 mW/m2.

  8. Constraints on post Mid-Jurassic basin evolution in the North Sea from 3D numerical modelling of basin initiation and subsidence.

    Science.gov (United States)

    Petersen, K. D.; Nielsen, S. B.

    2007-12-01

    The North Sea sedimentary basin contains more than 3km of post Mid-Jurassic sediments. These are located in a trilete graben system consisting of the Moray Firth and the Viking and Central grabens, but also in a broad region surrounding the grabens, corresponding to the post-mid Cretaceous sediment deposits During the Mid- Jurassic the area was exposed to volcanism, domal regional uplift and erosion, followed by crustal thinning and normal faulting in the grabens. We use a numerical model considering 3D thermal evolution, flexural isostasy, erosion, sedimentation and compaction together with isopach data to simulate the geodynamic evolution of the area since the Mid-Jurassic. Our modelling studies show that the broad distribution of post Jurassic sediments cannot be explained by uniform stretching in the graben areas alone. Regional Mid-Jurassic thinning of the subcrustal lithosphere producing first uplift and erosion and later accommodation space for Cretaceous and Cenozoic sediments is also required. The uniform crustal thinning factor in the grabens amounts to a maximum of 1.14. The required subcrustal lithospheric thinning amounts to about 15 km. Our results are in accordance with observations from recent rift systems such as the Rhine Graben, Eastern Africa and the Baikal Rift, which show that crustal thinning is restricted to the graben areas while thinning of the subcrustal lithosphere (up to 100 km) and the associated domal surface uplift are more regionally distributed.

  9. A case of Distributed Continental Collision: Late Cretaceous Intraplate Shortening from Central Europe to North Africa

    Science.gov (United States)

    Kley, J.; Voigt, T.; Jaehne, F.

    2008-12-01

    Intraplate thrusting and basin inversion affected west-central Europe in Late Cretaceous time. The timing of this event is fairly well constrained between c. 90 and 65 Ma. The dominantly NW-trending European intraplate structures were often interpreted to have been dextrally transpressive, reflecting a northward push induced by the early collision of the Adria microplate with Europe's southern margin. However, many fault kinematic and other structural data from central Europe indicate dip-slip contraction essentially perpendicular to the main faults, suggesting a push from the southwest. In addition, recent plate reconstructions of the Mediterranean around 85 Ma place Adria far to the southeast and roughly along strike of the central European intraplate structures. The early Alpine nappe stack on Adria's leading edge was still separated from Europe by subducting oceanic lithosphere and had entered a phase of extension after the first orogenic event. All this makes Alpine collision an unlikely cause for intraplate thrusting in Europe. Rather, the timing, kinematics and location of structures suggest that intraplate shortening in Europe was a direct effect of convergence with the Iberian and African plates, with stresses transmitted across the Azores-Gibraltar fracture zone. This hypothesis is supported by structures of Late Cretaceous age indicating SW-NE to S-N shortening in France, Spain (particularly the onset of convergence in the Pyrenees) and northwestern Africa. In contrast to other examples such as the Laramides, intraplate thrusting in this case was not a foreland phenomenon related to a coeval orogen. It does not reflect a transition from subduction to continental collision, but the beginning of convergence across two former transform boundaries. This system which included no strongly thickened and weakened crust was mostly governed by far-field stresses and therefore responded rapidly to plate reorganizations. Specifically, the onset of thrusting

  10. North-south palaeohydrological contrasts in the central Mediterranean during the Holocene: tentative synthesis and working hypotheses

    Science.gov (United States)

    Magny, M.; Combourieu-Nebout, N.; de Beaulieu, J. L.; Bout-Roumazeilles, V.; Colombaroli, D.; Desprat, S.; Francke, A.; Joannin, S.; Ortu, E.; Peyron, O.; Revel, M.; Sadori, L.; Siani, G.; Sicre, M. A.; Samartin, S.; Simonneau, A.; Tinner, W.; Vannière, B.; Wagner, B.; Zanchetta, G.; Anselmetti, F.; Brugiapaglia, E.; Chapron, E.; Debret, M.; Desmet, M.; Didier, J.; Essallami, L.; Galop, D.; Gilli, A.; Haas, J. N.; Kallel, N.; Millet, L.; Stock, A.; Turon, J. L.; Wirth, S.

    2013-09-01

    by two major climate changes around 7500 and 4500 cal BP. In the central Mediterranean, the Holocene palaeohydrological changes developed in response to a combination of orbital, ice-sheet and solar forcing factors. The maximum humidity interval in the south-central Mediterranean started ca. 10 300 cal BP, in correlation with the decline (1) of the possible blocking effects of the North Atlantic anticyclone linked to maximum insolation, and/or (2) of the influence of the remnant ice sheets and fresh water forcing in the North Atlantic Ocean. In the north-central Mediterranean, the lake-level minimum interval began only around 9000 cal BP when the Fennoscandian ice sheet disappeared and a prevailing positive NAO-(North Atlantic Oscillation) type circulation developed in the North Atlantic area. The major palaeohydrological oscillation around 4500-4000 cal BP may be a non-linear response to the gradual decrease in insolation, with additional key seasonal and interhemispheric changes. On a centennial scale, the successive climatic events which punctuated the entire Holocene in the central Mediterranean coincided with cooling events associated with deglacial outbursts in the North Atlantic area and decreases in solar activity during the interval 11 700-7000 cal BP, and to a possible combination of NAO-type circulation and solar forcing since ca. 7000 cal BP onwards. Thus, regarding the centennial-scale climatic oscillations, the Mediterranean Basin appears to have been strongly linked to the North Atlantic area and affected by solar activity over the entire Holocene. In addition to model experiments, a better understanding of forcing factors and past atmospheric circulation patterns behind the Holocene palaeohydrological changes in the Mediterranean area will require further investigation to establish additional high-resolution and well-dated records in selected locations around the Mediterranean Basin and in adjacent regions. Special attention should be paid to greater

  11. Thermal basin modelling of the Arauco forearc basin, south central Chile — Heat flow and active margin tectonics

    Science.gov (United States)

    Kuhn, Philipp P.; Echtler, Helmut; Littke, Ralf; Alfaro, Guillermo

    2010-11-01

    The Arauco basin is part of the coastal forearc domain in South-Central Chile. During its evolution since the Late Cretaceous it was subject to multiple deposition cycles and the erosion of lower bathyal to beach and lagoon sediments. These different environments were established in alternating accretional and erosive subduction tectonic settings along the South Andean active margin. Whereas the general development is well understood, inconsistencies arise regarding the origin of the high thermal maturity of Eocene coals and the estimates of vertical movements of the whole area during the Cenozoic. Thermal modelling of this forearc basin provides new insights regarding its thermal evolution and evaluation of the magnitudes of subsidence and inversion. Results are based on the analysis of coal samples from surface outcrops, mines and drill cores of ten onshore wells from ENAP/Sipetrol. Newly derived vitrinite reflectance (VR r) measurements indicated a temperature in the range of 135-150 °C for the oldest sediment unit of the Arauco basin, which was reached in post Eocene times. Furthermore, 1D basin modelling techniques indicate scenarios that could explain the coalification values in the basin's sediments. The models were calibrated against VR r data from drill core samples supplied by ENAP/Sipetrol. A Miocene and an Oligocene subsidence/inversion scenario were considered, while neither could be securely discarded based on the modelling results. Furthermore, it can be shown that the current thermal maturity was not reached by an increased heat flow (HF) or a deep subsidence only. Consequently, a structural inversion accompanied by the erosion of ~ 3.0 ± 0.4 km depending on the locality in combination with a high HF of ~ 64 ± 4 mW/m 2 is the best explanation of the available data. The HF, which is high for a forearc setting, can be attributed to the increased temperature of the relatively young subducted Nazca Plate and an additional influence of ascending hot

  12. Meteorological, stream-discharge, and water-quality data for 1986 through 1991 from two small basins in central Nevada

    Energy Technology Data Exchange (ETDEWEB)

    McKinley, P.W.; Oliver, T.A.

    1994-04-01

    The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, is investigating the volcanic tuffs of Yucca Mountain, Nevada, for their suitability as storage sites for nuclear waste. Two small basins, measuring less than 2 square miles, were studied to determine the volume of precipitation available for recharge to the ground water. The semiarid 3 Springs Basin is located to the east of Kawich Peak in the Kawich Range east of Tonopah, Nevada. Stewart Basin is a subalpine drainage basin north of Arc Dome in the Toiyabe Range north of Tonopah, Nevada. This publication presents the meteorological, stream-discharge, and water-quality data collected during the study. Meteorological data collected include air temperature, soil temperature, solar radiation, and relative humidity. Stream-discharge data were collected from the surface-water outlet of each basin. Water-quality data are chemical analyses of water samples collected from surface- and ground-water sources. Data were collected throughout the two basins. Each basin has a meteorological station located in the lower and upper reaches of the basin. Hydrologic records include stream-discharge and water-quality data from the lower meteorological site and water-quality data from springs within the basins. Meteorological data are available from the lower sites from the winter of 1986 through the fall of 1991. Periods of data collection were shorter for additional sites in the basin.

  13. Analysing the origin of rain- and subsurface water in seasonal wetlands of north-central Namibia

    Science.gov (United States)

    Hiyama, Tetsuya; Kanamori, Hironari; Kambatuku, Jack R.; Kotani, Ayumi; Asai, Kazuyoshi; Mizuochi, Hiroki; Fujioka, Yuichiro; Iijima, Morio

    2017-03-01

    We investigated the origins of rain- and subsurface waters of north-central Namibia’s seasonal wetlands, which are critical to the region’s water and food security. The region includes the southern part of the Cuvelai system seasonal wetlands (CSSWs) of the Cuvelai Basin, a transboundary river basin covering southern Angola and northern Namibia. We analysed stable water isotopes (SWIs) of hydrogen (HDO) and oxygen (H2 18O) in rainwater, surface water and shallow groundwater. Rainwater samples were collected during every rainfall event of the rainy season from October 2013 to April 2014. The isotopic ratios of HDO (δD) and oxygen H2 18O (δ 18O) were analysed in each rainwater sample and then used to derive the annual mean value of (δD, δ 18O) in precipitation weighted by each rainfall volume. Using delta diagrams (plotting δD vs. δ 18O), we showed that the annual mean value was a good indicator for determining the origins of subsurface waters in the CSSWs. To confirm the origins of rainwater and to explain the variations in isotopic ratios, we conducted atmospheric water budget analysis using Tropical Rainfall Measuring Mission (TRMM) multi-satellite precipitation analysis (TMPA) data and ERA-Interim atmospheric reanalysis data. The results showed that around three-fourths of rainwater was derived from recycled water at local–regional scales. Satellite-observed outgoing longwave radiation (OLR) and complementary satellite data from MODerate-resolution Imaging Spectroradiometer (MODIS) and Advanced Microwave Scanning Radiometer (AMSR) series implied that the isotopic ratios in rainwater were affected by evaporation of raindrops falling from convective clouds. Consequently, integrated SWI analysis of rain-, surface and subsurface waters, together with the atmospheric water budget analysis, revealed that shallow groundwater of small wetlands in this region was very likely to be recharged from surface waters originating from local rainfall, which was

  14. Hydrocarbon Source Rocks in the Deep River and Dan River Triassic Basins, North Carolina

    Science.gov (United States)

    Reid, Jeffrey C.; Milici, Robert C.

    2008-01-01

    This report presents an interpretation of the hydrocarbon source rock potential of the Triassic sedimentary rocks of the Deep River and Dan River basins, North Carolina, based on previously unpublished organic geochemistry data. The organic geochemical data, 87 samples from 28 drill holes, are from the Sanford sub-basin (Cumnock Formation) of the Deep River basin, and from the Dan River basin (Cow Branch Formation). The available organic geochemical data are biased, however, because many of the samples collected for analyses by industry were from drill holes that contained intrusive diabase dikes, sills, and sheets of early Mesozoic age. These intrusive rocks heated and metamorphosed the surrounding sediments and organic matter in the black shale and coal bed source rocks and, thus, masked the source rock potential that they would have had in an unaltered state. In places, heat from the intrusives generated over-mature vitrinite reflectance (%Ro) profiles and metamorphosed the coals to semi-anthracite, anthracite, and coke. The maximum burial depth of these coal beds is unknown, and depth of burial may also have contributed to elevated thermal maturation profiles. The organic geochemistry data show that potential source rocks exist in the Sanford sub-basin and Dan River basin and that the sediments are gas prone rather than oil prone, although both types of hydrocarbons were generated. Total organic carbon (TOC) data for 56 of the samples are greater than the conservative 1.4% TOC threshold necessary for hydrocarbon expulsion. Both the Cow Branch Formation (Dan River basin) and the Cumnock Formation (Deep River basin, Sanford sub-basin) contain potential source rocks for oil, but they are more likely to have yielded natural gas. The organic material in these formations was derived primarily from terrestrial Type III woody (coaly) material and secondarily from lacustrine Type I (algal) material. Both the thermal alteration index (TAI) and vitrinite reflectance data

  15. Influences of North Atlantic climate variability on low-flows in the Connecticut River Basin

    Science.gov (United States)

    Steinschneider, Scott; Brown, Casey

    2011-10-01

    SummaryConnections between summertime, ecologically relevant low-flow indicators and both winter and spring climate phenomena are explored for the Connecticut River Basin, with an emphasis on assessing forecast potential. Low-flow streamflow statistics deemed important for ecological health, including minimum 1-day mean flows, minimum 7-day mean flows, and monthly streamflow averages from June to September, are derived from 61 years of continuous, daily streamflow data at 15 United States Geological Survey streamflow gauging stations across the basin. Relationships between the ecological flow indicators with leading sea-surface temperature and sea-level pressure are investigated using correlation and composite analysis. Results suggest lagged relationships of up to 5 months between summer streamflow and the wintertime North Atlantic Oscillation, springtime east coast pressure trough, and springtime North Atlantic Tripole. These climate states have been linked to shifts between zonal and meridonal airflow as well as sea-surface temperature anomalies off the coast of the eastern US, both of which have implications for the movement of moisture systems over the study region. This study suggests that residual influences on airflow and sea-surface temperature persist into the summer following these earlier climate states, influencing low-flow hydrology in the region. As eco-hydrologic flow targets often conflict with other stakeholder objectives within a watershed, reservoir operators may utilize such lagged teleconnection patterns to predict annual low-flow characteristics in the region and help negotiate tradeoffs between traditional water management objectives and those emphasizing ecological conservation.

  16. Seasonality of Groundwater Recharge in the Basin and Range Province, Western North America

    Science.gov (United States)

    Neff, K. L.; Meixner, T.; Ajami, H.; De La Cruz, L.

    2015-12-01

    For water-scarce communities in the western U.S., it is critical to understand groundwater recharge regimes and how those regimes might shift in the face of climate change and impact groundwater resources. Watersheds in the Basin and Range Geological Province are characterized by a variable precipitation regime of wet winters and variable summer precipitation. The relative contributions to groundwater recharge by summer and winter precipitation vary throughout the province, with winter precipitation recharge dominant in the northern parts of the region, and recharge from summer monsoonal precipitation playing a more significant role in the south, where the North American Monsoon (NAM) extends its influence. Stable water isotope data of groundwater and seasonal precipitation from sites in Sonora, Mexico and the U.S. states of California, Nevada, Utah, Arizona, Colorado, New Mexico, and Texas were examined to estimate and compare groundwater recharge seasonality throughout the region. Contributions of winter precipitation to annual recharge vary from 69% ± 41% in the southernmost Río San Miguel Basin in Sonora, Mexico, to 100% ± 36% in the westernmost Mojave Desert of California. The Normalized Seasonal Wetness Index (NSWI), a simple water budget method for estimating recharge seasonality from climatic data, was shown to approximate recharge seasonality well in several winter precipitation-dominated systems, but less well in basins with significant summer precipitation.

  17. Evolution of physical and biological characteristics of mesoscale eddy in north-central Red Sea

    Science.gov (United States)

    Zarokanellos, Nikolaos; Jones, Burton

    2015-04-01

    Eddies appear to be important to both the physical and biogeochemical dynamics of the Red Sea. Numerical simulations of physical dynamics and remote sensing studies of chlorophyll concentration and sea surface height in the Red Sea indicate their importance to the upper portions of the sea (Raitsos et al., 2013; Yao et al., 2014; Zhan et al., 2014). Despite their apparent importance, process studies of these eddies have been lacking. In March 2013 we began an extended observational study of the north-central Red Sea (NCRS) where anticyclonic eddies have been observed. The study began with a ship-based characterization of the eddy and was followed by a three-month observational time series using an autonomous glider equipped with a CTD, oxygen sensor, and optical sensors for chlorophyll, CDOM and optical backscatter. The ship-based study captured an initial snapshot of an anticyclonic eddy and it's associated biological and bio-optical distributions. Initially, chlorophyll distributions tended to mirror the density distribution, with deeper isopycnals and chlorophyll maximum depth in the anticyclonic eddy center. The anticyclone eddy in March had an along basin diameter of 150 km, penetrated vertically less than 150 m and elevated near surface chlorophyll concentrations appeared along its outer boundary. The shallowing of the pycnocline of the outer boundaries of the anticyclone eddy on March may elevate nutrients into the lower euphotic zone, contributing to phytoplankton productivity and biomass within the eddy. This eddy contains most of the kinetic energy of the region with the maximum velocities up to 30 - 35 cm/s. The eddy appeared to interact with the coastal reefs where exchange particulate and dissolved matter may occur. The autonomous glider provided the spring-to-summer progression of the system with increasing stratification, shallowing of the subsurface chlorophyll maximum, and fluctuations in the position and intensity of the eddy. Our glider effort

  18. Evolution of physical and biological characteristics of mesoscale eddy in north-central Red Sea

    KAUST Repository

    Zarokanellos, Nikolaos

    2015-04-01

    Eddies appear to be important to both the physical and biogeochemical dynamics of the Red Sea. Numerical simulations of physical dynamics and remote sensing studies of chlorophyll concentration and sea surface height in the Red Sea indicate their importance to the upper portions of the sea (Raitsos et al., 2013; Yao et al., 2014; Zhan et al., 2014). Despite their apparent importance, process studies of these eddies have been lacking. In March 2013 we began an extended observational study of the north-central Red Sea (NCRS) where anticyclonic eddies have been observed. The study began with a ship-based characterization of the eddy and was followed by a three-month observational time series using an autonomous glider equipped with a CTD, oxygen sensor, and optical sensors for chlorophyll, CDOM and optical backscatter. The ship-based study captured an initial snapshot of an anticyclonic eddy and it\\'s associated biological and bio-optical distributions. Initially, chlorophyll distributions tended to mirror the density distribution, with deeper isopycnals and chlorophyll maximum depth in the anticyclonic eddy center. The anticyclone eddy in March had an along basin diameter of 150 km, penetrated vertically less than 150 m and elevated near surface chlorophyll concentrations appeared along its outer boundary. The shallowing of the pycnocline of the outer boundaries of the anticyclone eddy on March may elevate nutrients into the lower euphotic zone, contributing to phytoplankton productivity and biomass within the eddy. This eddy contains most of the kinetic energy of the region with the maximum velocities up to 30 - 35 cm/s. The eddy appeared to interact with the coastal reefs where exchange particulate and dissolved matter may occur. The autonomous glider provided the spring-to-summer progression of the system with increasing stratification, shallowing of the subsurface chlorophyll maximum, and fluctuations in the position and intensity of the eddy. Our glider effort

  19. CENTRAL OBESITY AND LIPID PROFILE IN NORTH INDIAN MALES

    OpenAIRE

    Nitesh Mishra; Manoj Kumar Sharma; Chandrasekhar, M.; Suresh, M; Ambareesha Kondam; Sanghishetty Vijay Prasad

    2012-01-01

    Obesity is a known risk factor for metabolic syndrome in adults. Metabolic syndrome includes agroup of cardiovascular disease risk factors namely impaired glucose tolerance, dyslipidaemia and hypertension.Central fat distribution, particularly intra-abdominal fat, is a greater risk factor than peripheral fat distribution.Anthropometric indices used to measure fat distribution have been shown to be associated with altered lipid profile.The objective of the present study was to compare the seru...

  20. A new species of Ischyodus (Chondrichthyes: Holocephali: Callorhynchidae) from Upper Maastrichtian Shallow marine facies of the Fox Hills and Hell Creek Formations, Williston basin, North Dakota, USA

    Science.gov (United States)

    Hoganson, J.W.; Erickson, J.M.

    2005-01-01

    A new species of chimaeroid, Ischyodus rayhaasi sp. nov., is described based primarily upon the number and configuration of tritors on palatine and mandibular tooth plates. This new species is named in honour of Mr Raymond Haas. Fossils of I. rayhaasi have been recovered from the Upper Maastrichtian Fox Hills Formation and the Breien Member and an unnamed member of the Hell Creek Formation at sites in south-central North Dakota and north-central South Dakota, USA. Ischyodus rayhaasi inhabited shallow marine waters in the central part of the Western Interior Seaway during the latest Cretaceous. Apparently it was also present in similar habitats at that time in the Volga region of Russia. Ischyodus rayhaasi is the youngest Cretaceous species Ischyodus known to exist before the Cretaceous/Tertiary extinction, and the species apparently did not survive that event. It was replaced by Ischyodus dolloi, which is found in the Paleocene Cannonball Formation of the Williston Basin region of North Dakota and is widely distributed elsewhere. ?? The Palaeontological Association.

  1. Nutrients, suspended sediment, and pesticides in waters of the Red River of the North Basin, Minnesota, North Dakota, and South Dakota, 1970-90

    Science.gov (United States)

    Tornes, L.H.; Brigham, M.E.

    1994-01-01

    Available data on nutrients (phosphorus and nitrogen), suspended sediment, and pesticides in the Red River of the North Basin, a study unit under the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program, are reviewed. These data were collected by several agencies during 1970-90. Nutrient concentrations in surface water are higher downgradient from agricultural and urban areas than in other areas, but generally do not exceed U.S. Environmental Protection Agency (USEPA) Maximum Contaminant Levels (MCLs). The 10 milligram per liter (mg/L) drinking water MCL for nitrate (as nitrogen) was rarely exceeded. Some of the largest nutrient inputs to the surface-water system appear to come from the Fargo-Moorhead area. The highest nitrogen concentrations usually were found in the Red River of the North. Nitrogen composition was mostly organic nitrogen with some nitrate. Ammonia nitrogen was negligible except during mid-winter, when concentrations could exceed 1.0 mg/L. Streams draining the corn-dominated cropland in the southern part of the basin had relatively high nitrogen concentrations compared to parts of the basin where small-grain crops, forests, and wetlands predominate. The Pembina River in the northern part of the basin had a large range in nitrogen concentrations that often exceeded those in the Red River of the North. The highest phosphorus concentrations generally were found in of the Red River of the North, although tributary streams occasionally had peak concentrations that exceeded those in the Red River of the North. Median nitrate concentrations in ground water were less than 1.0 mg/L as nitrogen in all counties in the basin except in Otter Tail and Decker Counties in Minnesota. Half of the wells in Otter Tail County had nitrate-nitrogen concentrations exceeding 2.8 mg/L. Shallow, surficial aquifers tended to have the highest nitrate concentrations.

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

    Science.gov (United States)

    Bahlburg, H.; Breitkreuz, C.

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

  3. Spatio-Temporal Identification of Areas Suitable for West Nile Disease in the Mediterranean Basin and Central Europe.

    Directory of Open Access Journals (Sweden)

    Annamaria Conte

    Full Text Available West Nile virus (WNV is a mosquito-transmitted Flavivirus belonging to the Japanese encephalitis antigenic complex of the Flaviviridae family. Its spread in the Mediterranean basin and the Balkans poses a significant risk to human health and forces public health officials to constantly monitor the virus transmission to ensure prompt application of preventive measures. In this context, predictive tools indicating the areas and periods at major risk of WNV transmission are of paramount importance. Spatial analysis approaches, which use environmental and climatic variables to find suitable habitats for WNV spread, can enhance predictive techniques. Using the Mahalanobis Distance statistic, areas ecologically most suitable for sustaining WNV transmission were identified in the Mediterranean basin and Central Europe. About 270 human and equine clinical cases notified in Italy, Greece, Portugal, Morocco, and Tunisia, between 2008 and 2012, have been considered. The environmental variables included in the model were altitude, slope, night time Land Surface Temperature, Normalized Difference Vegetation Index, Enhanced Vegetation Index, and daily temperature range. Seasonality of mosquito population has been modelled and included in the analyses to produce monthly maps of suitable areas for West Nile Disease. Between May and July, the most suitable areas are located in Tunisia, Libya, Egypt, and North Cyprus. Summer/Autumn months, particularly between August and October, characterize the suitability in Italy, France, Spain, the Balkan countries, Morocco, North Tunisia, the Mediterranean coast of Africa, and the Middle East. The persistence of suitable conditions in December is confined to the coastal areas of Morocco, Tunisia, Libya, Egypt, and Israel.

  4. Spatio-Temporal Identification of Areas Suitable for West Nile Disease in the Mediterranean Basin and Central Europe

    Science.gov (United States)

    Conte, Annamaria; Candeloro, Luca; Ippoliti, Carla; Monaco, Federica; De Massis, Fabrizio; Bruno, Rossana; Di Sabatino, Daria; Danzetta, Maria Luisa; Benjelloun, Abdennasser; Belkadi, Bouchra; El Harrak, Mehdi; Declich, Silvia; Rizzo, Caterina; Hammami, Salah; Ben Hassine, Thameur; Calistri, Paolo; Savini, Giovanni

    2015-01-01

    West Nile virus (WNV) is a mosquito-transmitted Flavivirus belonging to the Japanese encephalitis antigenic complex of the Flaviviridae family. Its spread in the Mediterranean basin and the Balkans poses a significant risk to human health and forces public health officials to constantly monitor the virus transmission to ensure prompt application of preventive measures. In this context, predictive tools indicating the areas and periods at major risk of WNV transmission are of paramount importance. Spatial analysis approaches, which use environmental and climatic variables to find suitable habitats for WNV spread, can enhance predictive techniques. Using the Mahalanobis Distance statistic, areas ecologically most suitable for sustaining WNV transmission were identified in the Mediterranean basin and Central Europe. About 270 human and equine clinical cases notified in Italy, Greece, Portugal, Morocco, and Tunisia, between 2008 and 2012, have been considered. The environmental variables included in the model were altitude, slope, night time Land Surface Temperature, Normalized Difference Vegetation Index, Enhanced Vegetation Index, and daily temperature range. Seasonality of mosquito population has been modelled and included in the analyses to produce monthly maps of suitable areas for West Nile Disease. Between May and July, the most suitable areas are located in Tunisia, Libya, Egypt, and North Cyprus. Summer/Autumn months, particularly between August and October, characterize the suitability in Italy, France, Spain, the Balkan countries, Morocco, North Tunisia, the Mediterranean coast of Africa, and the Middle East. The persistence of suitable conditions in December is confined to the coastal areas of Morocco, Tunisia, Libya, Egypt, and Israel. PMID:26717483

  5. Late Yanshan-Himalayan hydrocarbon reservoir adjustment and hydrotherrnal fluid activity in the central Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The adjustment of primary hydrocarbon reservoirs in marine formations is an important feature of the oil pools in the Tarim Basin. Large-scale hydrocarbon adjustment is related to the strong regional tectonic movements, which is always accompanied by extensive migration of basin fluids including diagenetic and mineralizing fluids. Organic fluid inclusions are well developed in hydrothermal minerals, such as fluorite, which have been found in the dissolution-enlarged fractures or karstification caves in the Ordovician in the central Tarim Basin. Proved by well drilling, the fluorite deposit is good reservoir for oil and gas. So the peculiar accompanied or superimposed relationship between fluorite hydrothermal fluid mineralization and hydrocarbon migration and accumulation exists in the Ordovician in the central Tarim Basin. Considering regional tectonic setting and mineralization condition,through different kinds of analytic methods including electron spin resonance dating, fluid inclusion laser Raman and colonial inclusions hydrocarbon fossil analysis, we proposed that extensive mineralizing fluids and hydrocarbon migration occurred in late Yanshan-Himalayan (110.4-30.8 Ma) period, and Himalayan, especially, is an important period for hydrocarbon accumulation from 34.3 Ma to present.

  6. Climate change adaptation in a highly urbanized snowmelt dominated basin in Central Chile

    Science.gov (United States)

    Vicuna, S.; Bustos, E.; Merino, P.; Henriquez Dole, L. E.; Jansen, S.; Gil, M.; Ocampo, A.; Poblete, D.; Tosoni, D.; Meza, F. J.; Donoso, G.; Melo, O.

    2015-12-01

    The Maipo river basin holds 40% of Chile's total population and produces almost half of the country's Gross Domestic Product. The basin is located in the semiarid and snowmelt dominated central region of the country and, aside from the typical pressures of growth in developing country basins, the Maipo river basin faces climate change impacts associated with a reduction in total runoff and changes in its seasonality. Surface water is the main water source for human settlements, natural ecosystems, and economic activities including agriculture, mining and hydropower production. In 2012 a research project, called MAPA (Maipo Plan de Adaptacion), began with the objective of articulating a climate variability and climate change adaptation plan for the Maipo river basin. The project engaged at the beginning a group of relevant water and land use stakeholders which allowed for a good representation of critical aspects of an adaptation plan such as the definition of objectives and performance indicators, future land use scenarios, modeling of the different components of the system and design of adaptation strategies. The presentation will highlight the main results of the research project with a special focus on the upper catchments of the basin. These results include the assessment of impacts associated with future climate and land use scenarios on key components of the hydrologic cycle including snowmelt and glacier contribution to runoff and subsequent impacts on water availability for the operation of hydropower facilities, satisfaction of instream (recreation and aquatic ecosystem) uses and provision of water for the city of Santiago (7 million people) and to irrigate more than 100,000 hectares of high value crops. The integrative approach followed in this project including different perspectives on the use of water in the basin provides a good opportunity to test the varying degree of impacts that could be associated with a given future scenario and also understand

  7. Mesozoic fill-sequences in Hefei Basin: Implication for Dabie Orogenesis, central China

    Institute of Scientific and Technical Information of China (English)

    LI; Zhong; SUN; Shu; LI; Renwei; JIANG; Maosheng

    2001-01-01

    A research on the Mesozoic fill-sequences of Hefei basin, located at the north foot of Dabie Mountains, shows two-phase evolution. The first phase, early- to mid-/late-Jurassic, is characterized by terrestrial clastic deposits, with four times of reverse-grading units at least, and forms greatly thick molass reconstruction in the mid-/late-phase, which reflects gradually strong thrusting-orogenesis in the north Dabie and flexural depression in the north foreland of Dabie Mountains. The second phase, late-Jurassic to Cretaceous, includes two-episode rifting processes. The first episode (J3) shows calc-alkalic and alkali volcanic rocks interstratified pyroclastic rocks, which may reflect upwelling igneous magma from mantle-source due to the Yangtze continent slab breakoff induced by deep subduction process. A suite of lacustrine, fluvial and piemount facies, about 3000?/FONT>3500 m in thickness, develops in the second episode (J3 -K1), which reflects regional extensional setting and intense elevator diversity of mountain-basin in the study area. This research renews and deepens cognition for the Mesozoic Dabie orogenesis.

  8. Mesozoic fill-sequences in Hefei Basin: Implication for Dabie Orogenesis, central China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A research on the Mesozoic fill-sequences of Hefei basin, locatedat the north foot of Dabie Mountains, shows two-phase evolution. The first phase, early- to mid-/late-Jurassic, is characterized by terrestrial clastic deposits, with four times of reverse-grading units at least, and forms greatly thick molass reconstruction in the mid-/late-phase, which reflects gradually strong thrusting-orogenesis in the north Dabie and flexural depression in the north foreland of Dabie Mountains. The second phase, late-Jurassic to Cretaceous, includes two-episode rifting processes. The first episode (J3) shows calc-alkalic and alkali volcanic rocks interstratified pyroclastic rocks, which may reflect upwelling igneous magma from mantle-source due to the Yangtze continent slab breakoff induced by deep subduction process. A suite of lacustrine, fluvial and piemount facies, about 3000?/FONT>3500 m in thickness, develops in the second episode (J3 -K1), which reflects regional extensional setting and intense elevator diversity of mountain-basin in the study area. This research renews and deepens cognition for the Mesozoic Dabie orogenesis.

  9. Late Permian Melt Percolation through the Crust of North-Central Africa and Its Possible Relationship to the African Large Low Shear Velocity Province

    Science.gov (United States)

    Shellnutt, J. G.; Lee, T. Y.; Yang, C. C.; Wu, J. C.; Wang, K. L.; Lo, C. H.

    2014-12-01

    The Doba gabbro was collected from an exploration well through the Cretaceous Doba Basin of Southern Chad. The gabbro is comprised mostly of plagioclase, clinopyroxene and Fe-Ti oxide minerals and displays cumulus mineral textures. Whole rock 40Ar/39Ar step-heating geochronology yielded a Late Permian plateau age of 257 ± 1 Ma. The major and trace elemental geochemistry shows that the gabbro is mildly alkalic to tholeiitic in composition and has trace element ratios (i.e. La/YbN > 7; Sm/YbPM > 3.4; Nb/Y > 1; Zr/Y > 5) indicative of a basaltic melt derived from a garnet-bearing sublithospheric mantle source. The moderately enriched Sr-Nd isotopes (i.e. ISr = 0.70495 to 0.70839; eNd(T) = -1.0 to -1.3) fall within the mantle array (i.e. OIB-like) and are similar to other Late Permian plutonic rocks of North-Central Africa (i.e. ISr = 0.7040 to 0.7070). The Late Permian plutonic igneous complexes of North-Central Africa are geologically associated with tectonic lineaments suggesting they acted as conduits for sublithospheric melts to migrate to middle/upper crustal levels. The source of the magmas may be related to the spatial-temporal association of North-Central Africa with the African large low shear velocity province (LLSVP). The African LLSVP has remained stable since the Late Carboniferous and was beneath the Doba basin during the Permian. We suggest that melts derived from deep seated sources related to the African LLSVP percolated through the North-Central African crust via older tectonic lineaments and form a discontiguous magmatic province.

  10. Petrographical indicators of petrogenesis: Examples from Central Indian Ocean Basin basalts

    Digital Repository Service at National Institute of Oceanography (India)

    Mislankar, P.G.; Iyer, S.D.

    crystals in glass, grades into the innermost holocrystalline zone C that has intergranular, intersertal and (Fig. 3d) flow (Fig. 3e) textures. Fig. 1Location of rock samples (solid dots) recovered from the Central Indian Ocean Basin and used... of alteration. The glassy portions in the groundmass form cholorophaeite, palagonite and smectite with the presence of reddish-brown globular structures (Fig. 4h). This is similar to the “red- feathery alteration” in which small plagioclase crystals form...

  11. Patterns of genetic diversity in Hepatozoon spp. infecting snakes from North Africa and the Mediterranean Basin.

    Science.gov (United States)

    Tomé, Beatriz; Maia, João P; Salvi, Daniele; Brito, José C; Carretero, Miguel A; Perera, Ana; Meimberg, Harald; Harris, David James

    2014-03-01

    Species of Hepatozoon Miller, 1908 are blood parasites most commonly found in snakes but some have been described from all tetrapod groups and a wide variety of hematophagous invertebrates. Previous studies have suggested possible associations between Hepatozoon spp. found in predators and prey. Particularly, some saurophagous snakes from North Africa and the Mediterranean region have been found to be infected with Hepatozoon spp. similar to those of various sympatric lizard hosts. In this study, we have screened tissue samples of 111 North African and Mediterranean snakes, using specific primers for the 18S rRNA gene. In the phylogenetic analysis, the newly-generated Hepatozoon spp. sequences grouped separately into five main clusters. Three of these clusters were composed by Hepatozoon spp. also found in snakes and other reptiles from the Mediterranean Basin and North Africa. In the other two clusters, the new sequences were not closely related to geographically proximate known sequences. The phylogeny of Hepatozoon spp. inferred here was not associated with intermediate host taxonomy or geographical distribution. From the other factors that could explain these evolutionary patterns, the most likely seems series of intermediate hosts providing similar ribotypes of Hepatozoon and a high prevalence of host shifts for Hepatozoon spp. This is indicated by ribotypes of high similarity found in different reptile families, as well as by divergent ribotypes found in the same host species. This potentially low host specificity has profound implications for the systematics of Hepatozoon spp.

  12. A tectonically controlled basin-fill within the Valle del Cauca, West-Central Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Rine, J.M.; Keith, J.F. Jr.; Alfonso, C.A.; Ballesteros, I.; Laverde, F.; Sacks, P.E.; Secor, D.T. Jr. (Univ. of South Carolina, Columbia (United States)); Perez, V.E.; Bernal, I.; Cordoba, F.; Numpaque, L.E. (Ecopetrol, Bogota (Colombia))

    1993-02-01

    Tertiary strata of the Valle del Cauca reflect a forearc/foreland basin tectonic history spanning a period from pre-uplift of the Cordillera Central to initiation of uplift of the Cordillera Occidental. Stratigraphy of the Valle del Cauca begins with Jurassic-Cretaceous rocks of exotic and/or volcanic provenance and of oceanic origin. Unconformably overlying these are Eocene to Oligocene basal quartz-rich sandstones, shallow marine algal limestones, and fine-grained fluvial/deltaic mudstones and sandstones with coalbeds. These Eocene to Oligocene deposits represent a period of low tectonic activity. During late Oligocene to early Miocene, increased tectonic activity produced conglomeratic sediments which were transported from east to west, apparently derived from uplift of the Cordillera Central, and deposited within a fluvial to deltaic setting. East-west shortening of the Valle del Cauca basin folded the Eocene to early Miocene units, and additional uplift of the Cordillera Central during the later Miocene resulted in syn-tectonic deposition of alluvial fans. After additional fold and thrust deformation of the total Eocene-Miocene basin-fill, tectonic activity abated and Pliocene-Quaternary alluvial and lacustrine strata were deposited. Within the framework of this depositional and tectonic history of the Valle del Cauca, hydrocarbon exploration strategies can be formulated and evaluated.

  13. Salar de Atacama basin: A record of compressional tectonics in the central Andes since the mid-Cretaceous

    OpenAIRE

    ARRIAGADA, César; Cobbold, Peter,; Roperch, Pierrick

    2006-01-01

    19 p.; International audience; The Salar de Atacama basin lies in the inner fore arc of northern Chile. Topographically and structurally, it is a first-order feature of the central Andes. The sedimentary fill of the basin constrains the timing and extent of crustal deformation since the mid-Cretaceous. We have studied good exposures along the western edge of the basin and have correlated them with seismic reflection sections and data from an exploration well. Throughout most of its history, t...

  14. Late Holocene Drought Record From Castor Lake, North-Central Washington State

    Science.gov (United States)

    Nelson, D. B.; Abbott, M. B.; Polissar, P. J.; Finney, B.

    2006-12-01

    The effects of recent and historic drought in the North American west provide motivation for understanding the natural variability and underlying causes of these events. We present a 6,000-year lake sediment record of water balance from Washington State in an effort to address these questions. A series of overlapping sediment cores were collected and chronological control was established through a combination of radiocarbon, tephrochronology, and cesium isotope activity. Modern basin morphometry and lake water oxygen and hydrogen isotope data indicate closed-basin hydrology and the strong influence of evaporative enrichment on lake water composition, and therefore sensitivity of the system to changes in regional water balance and drought. Samples of endogenic aragonite precipitates were isolated from sediment cores at an average sampling interval of 3.7mm, corresponding to a temporal resolution of approximately 7 years. Grayscale data were generated from digital images of the cores collected under controlled light conditions and are shown to track changes in oxygen isotope values, with darker layers corresponding to periods of increased isotopic composition. In addition to supporting the notion that oxygen isotope data are primarily recording changes in water balance as opposed to changes in water source or temperature, the increased resolution of the grayscale record improves the resolution of the climate signal to the sub-millimeter scale of the laminations. There is a significant correlation between the most recent portion of the Castor Lake grayscale record and a 1,500-yr Palmer Drought Severity Index (PDSI) reconstruction from central Washington (1). The strong association between changes in the Castor Lake record and changes in the PDSI reconstruction provides convincing method validation and strengthens the interpretation of both as drought signals. Spectral analyses of the grayscale record using singular spectrum analysis (SSA), maximum entropy method (MEM

  15. Geohydrology and numerical simulation of groundwater flow in the central Virgin River Basin of Iron and Washington Counties, Utah

    Science.gov (United States)

    Heilweil, V.M.; Freethey, G.W.; Wilkowske, C.D.; Stolp, B.J.; Wilberg, D.E.

    2000-01-01

    Because rapid growth of communities in Washington and Iron Counties, Utah, is expected to cause an increase in the future demand for water resources, a hydrologic investigation was done to better understand ground-water resources within the central Virgin River basin. This study focused on two of the principal ground-water reservoirs within the basin: the upper Ash Creek basin ground-water system and the Navajo and Kayenta aquifer system.The ground-water system of the upper Ash Creek drainage basin consists of three aquifers: the uppermost Quaternary basin-fill aquifer, the Tertiary alluvial-fan aquifer, and the Tertiary Pine Valley monzonite aquifer. These aquifers are naturally bounded by the Hurricane Fault and by drainage divides. On the basis of measurements, estimates, and numerical simulations of reasonable values for all inflow and outflow components, total water moving through the upper Ash Creek drainage basin ground-water system is estimated to be about 14,000 acre-feet per year. Recharge to the upper Ash Creek drainage basin ground-water system is mostly from infiltration of precipitation and seepage from ephemeral and perennial streams. The primary source of discharge is assumed to be evapotranspiration; however, subsurface discharge near Ash Creek Reservoir also may be important.The character of two of the hydrologic boundaries of the upper Ash Creek drainage basin ground-water system is speculative. The eastern boundary provided by the Hurricane Fault is assumed to be a no-flow boundary, and a substantial part of the ground-water discharge from the system is assumed to be subsurface outflow beneath Ash Creek Reservoir along the southern boundary. However, these assumptions might be incorrect because alternative numerical simulations that used different boundary conditions also proved to be feasible. The hydrogeologic character of the aquifers is uncertain because of limited data. Differences in well yield indicate that there is considerable

  16. Interactions between surface water and ground water and effects on mercury transport in the north-central Everglades

    Science.gov (United States)

    Harvey, Judson W.; Krupa, Steven L.; Gefvert, Cynthia; Mooney, Robert H.; Choi, Jungyill; King, Susan A.; Giddings, Jefferson B.

    2002-01-01

    The hydrology of the north-central Everglades was altered substantially in the past century by canal dredging, land subsidence, ground-water pumping, and levee construction. Vast areas of seasonal and perennial wetlands were converted to uses for agriculture, light industry, and suburban development. As the catchment area for the Everglades decreased, so did the sources of water from local precipitation and runoff from surrounding uplands. Partly in response to those alterations, water-resources managers compartmentalized the remaining wetlands in the north-central Everglades into large retention basins, called Water Conservation Areas (WCAs). In spite of efforts to improve how water resources are managed, the result has been frequent periods of excessive drying out or flooding of the WCAs because the managed system does not have the same water-storage capacity as the pre-drainage Everglades. Linked to the hydrological modifications are ecological changes including large-scale invasions of cattail, loss of tree islands, and diminishing bird populations in the Everglades. Complex interactions among numerous physical, chemical, and biological factors are responsible for the long-term degradation of the ecological character of the Everglades.Over the past 15 years, a new set of smaller wetland basins, called Stormwater Treatment Areas (STAs), have been designed and constructed by water-resources engineers on the former wetlands adjacent to WCAs. The purpose of STAs is to remove excess nutrients from agricultural drainage water prior to its input to WCAs. STAs tend to be about one-tenth the size of a WCA, and they are located on former wetlands on the northwestern side of WCAs on sites that were managed as farmland for much of the twentieth century in an area referred to as the Everglades Agricultural Area, or EAA. The objective of the present investigation was to quantify interactions between surface water and ground water in the Everglades Nutrient Removal Project

  17. Evolution of the central Walvis Basin / offshore NW Namibia - balancing onshore erosion and offshore sedimentation

    Science.gov (United States)

    Henk, A.; Kukulus, M.; Junker, R.

    2003-04-01

    Rifting and break-up of Gondwana in the Late Jurassic / Early Cretaceous led to formation of the South Atlantic. One of the associated passive margins, the Walvis Basin in NW Namibia, is used as a case study to investigate the mass and process balances which link uplift and erosion onshore to contemporaneous subsidence and sedimentation offshore. One of the main objectives of the project is to gain quantitative insights into the feedback mechanisms between surface processes and lithospheric processes during passive margin evolution. Modeling concentrates on a traverse across the central Walvis Basin and adjacent onshore areas. Mass balancing requires a reconstruction of the denudation history and the volumes eroded onshore as well as a quantification of the contemporaneous sedimentary record preserved offshore. In the offshore parts of the study area, seismic sections and well data are available to constrain the post-rift evolution of the Walvis basin. However, as none of the exploration wells has yet reached syn-rift deposits, the early margin evolution has to remain speculative. In the onshore part of the traverse, field evidence and published apatite fission track data are used to reconstruct the erosion history. Comparison of the eroded and deposited volumes and masses, respectively, reveals a misfit of about 50 %, i.e. only half of the sediments observed offshore can be attributed to nearby source areas onshore. This result is supported by provenance analysis on cuttings from an offshore well which indicate that a substantial part of the detritus was derived from sources to the south and transported to the central Walvis Basin by coast-parallel currents. Sediment supply rates derived from reconstruction of the onshore erosion history and subsidence rates based on lithospheric cooling models together with global sea level changes are then used to model quantitatively deposition and stratigraphic architectures of the post-rift succession in the central Walvis

  18. Tropical Cyclone Activity in the North Atlantic Basin During the Weather Satellite Era, 1960-2014

    Science.gov (United States)

    Wilson, Robert M.

    2016-01-01

    This Technical Publication (TP) represents an extension of previous work concerning the tropical cyclone activity in the North Atlantic basin during the weather satellite era, 1960-2014, in particular, that of an article published in The Journal of the Alabama Academy of Science. With the launch of the TIROS-1 polar-orbiting satellite in April 1960, a new era of global weather observation and monitoring began. Prior to this, the conditions of the North Atlantic basin were determined only from ship reports, island reports, and long-range aircraft reconnaissance. Consequently, storms that formed far from land, away from shipping lanes, and beyond the reach of aircraft possibly could be missed altogether, thereby leading to an underestimate of the true number of tropical cyclones forming in the basin. Additionally, new analysis techniques have come into use which sometimes has led to the inclusion of one or more storms at the end of a nominal hurricane season that otherwise would not have been included. In this TP, examined are the yearly (or seasonal) and 10-year moving average (10-year moving average) values of the (1) first storm day (FSD), last storm day (LSD), and length of season (LOS); (2) frequencies of tropical cyclones (by class); (3) average peak 1-minute sustained wind speed () and average lowest pressure (); (4) average genesis location in terms of north latitudinal () and west longitudinal () positions; (5) sum and average power dissipation index (); (6) sum and average accumulated cyclone energy (); (7) sum and average number of storm days (); (8) sum of the number of hurricane days (NHD) and number of major hurricane days (NMHD); (9) net tropical cyclone activity index (NTCA); (10) largest individual storm (LIS) PWS, LP, PDI, ACE, NSD, NHD, NMHD; and (11) number of category 4 and 5 hurricanes (N4/5). Also examined are the December-May (D-M) and June-November (J-N) averages and 10-year moving average values of several climatic factors, including the (1

  19. Seismicity surveying in central and north mexico region

    Science.gov (United States)

    Gómez, J. M.; Guzmán, M.; Nieto, A.; Zúñiga, R.; Alaniz, S.; Barboza, R.

    2003-04-01

    The seismic nature of Central Mexico is poorly understood due to insufficient sampling. This region is characterized by a very low deformation rate. The seismic activity is variable and ranges from microseismicity to large earthquakes. Some large earthquakes have occurred with an unknown returning period; structural studies show this recurrence could range from hundreds to thousands of years. Some authors argue that there is not connection between ancient and recent activity. We carried out several seismic surveys in part of the TransMexican Volcanic Belt (TMVB) and the Altiplano Central. We installed a temporal network, in order to record spatial seismic distribution. This network consists of 3-5 short period instruments, consisting of triaxial digital velocity recorders (0.01-4.5 Hz). We registered several swarms; one took place in Guanajuato and lasted for 2 weeks. Another crisis occurred at the northern limit of the TMVB at Sierra Gorda. Over five weeks several micro-earthquakes M < 2 were felt with anomaously high intensity. Relocated seismicity shows very shallow (< 10km) activity. The regional crust conditions appear to be roughly uniform even though the seismicity varies significantly. In some cases like seismic swarms, several microearthquakes are aligned, and seem to be quasi-parallel to the direction of the fault strike, some other times they are perpendicular. However, surface ruptures associated to earthquakes are not observed to confirm this. Then, a challenge is to locate the seismogenic structures, basically because of the surface structures are too old to be still active. Increased seismotectonic knowledge of this region may give further insight into the details of the interaction between surface structures driven by the regional stress field.

  20. Seismicity Surveying in Central and North Mexico Regions

    Science.gov (United States)

    Nieto-Samaniego, A.; Gomez-Gonzalez, J. M.; Guzman-Speziale, M.; Zuniga, R.; Alaniz-Alvarez, S.; Barboza, R.; Davalos, O.

    2003-12-01

    The seismic nature of Central Mexico is poorly understood due to insufficient sampling. We carried out a seismic survey in part of the TransMexican Volcanic Belt (TMVB) and the Central Altiplano. These regions are characterized by a very low deformation rates. Seismic activity is variable and ranges from microseismicity to large earthquakes, but no large historic earthquake has been instrumentally recorded. Only few direct observations such as intensity reconstructions and recent paleoseismic studies (e.g. the Acambay-Tixmadej earthquake of 1912) are available. Large earthquakes have occurred but their recurrence period is unknown; structural studies show this recurrence could range from hundreds to thousands of years. In order to understand the regional seismic behavior, we installed a temporal network. This network consists of 3-5 short period instruments, consisting of 16-bits triaxial digital velocity recorders (0.01-4.5 Hz). We registered several seismic sequences over a period of several months. One of them took place in Guanajuato within a graben structure in the TMVB and lasted for 2 weeks. Another sequence occurred at the northern limit of the TMVB in the Sierra Gorda. Over five weeks, several micro-earthquakes M Sierra Gorda, the event distribution is aligned along a small valley, but perpendicular to the main structural grain imposed by the Sierra Madre Oriental range. In no instances have surface ruptures been observed; those seismogenic structures could be blind ones. A challenge is to locate this structures which are may be too old to be still active. Increased seismotectonic knowledge of this region will yield further insight into the details of the interaction between surface structures driven by the regional stress field. Our results provide evidence that the region requires more intensive seismic surveying, and in some cases that some structures have been reactivated recently.

  1. Hydrogeologic Framework and Ground Water in Basin-Fill Deposits of the Diamond Valley Flow System, Central Nevada

    Science.gov (United States)

    Tumbusch, Mary L.; Plume, Russell W.

    2006-01-01

    The Diamond Valley flow system, an area of about 3,120 square miles in central Nevada, consists of five hydrographic areas: Monitor, Antelope, Kobeh, and Diamond Valleys and Stevens Basin. Although these five areas are in a remote part of Nevada, local government officials and citizens are concerned that the water resources of the flow system eventually could be further developed for irrigation or mining purposes or potentially for municipal use outside the study area. In order to better understand the flow system, the U.S. Geological Survey in cooperation with Eureka, Lander, and Nye Counties and the Nevada Division of Water Resources, is conducting a multi-phase study of the flow system. The principal aquifers of the Diamond Valley flow system are in basin-fill deposits that occupy structural basins comprised of carbonate rocks, siliciclastic sedimentary rocks, igneous intrusive rocks, and volcanic rocks. Carbonate rocks also function as aquifers, but their extent and interconnections with basin-fill aquifers are poorly understood. Ground-water flow in southern Monitor Valley is from the valley margins toward the valley axis and then northward to a large area of discharge by evapotranspiration (ET) that is formed south of a group of unnamed hills near the center of the valley. Ground-water flow from northern Monitor Valley, Antelope Valley, and northern and western parts of Kobeh Valley converges to an area of ground-water discharge by ET in central and eastern Kobeh Valley. Prior to irrigation development in the 1960s, ground-water flow in Diamond Valley was from valley margins toward the valley axis and then northward to a large discharge area at the north end of the valley. Stevens Basin is a small upland basin with internal drainage and is not connected with other parts of the flow system. After 40 years of irrigation pumping, a large area of ground-water decline has developed in southern Diamond Valley around the irrigated area. In this part of Diamond

  2. Bacterial standing stock, meiofauna and sediment-nutrient characteristics: Indicators of benthic disturbance in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; LokaBharathi, P.A.; Ansari, Z.A.; Nair, S.; Ingole, B.S.; Sheelu, G.; Mohandass, C.; Nath, B.N.; Rodrigues, N.

    As a part of the environmental impact assessment studies for polymetallic nodule mining, the effect of simulated "benthic disturbance" caused by a benthic hydraulic disturber was studied in the Central Indian Basin (CIB). The abundance...

  3. A study on the evolution of Indian Ocean triple junction and the process of deformation in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Murthy, K.S.R.; Rao, T.C.S.

    It is generally presumed that the intraplate deformation in the Central Indian Basin (CIB) is a direct consequence of spreading across the South East Indian Ridge and the resistance to shortening at the continental collision between India...

  4. The nitrogen budget for different forest types in the central Congo Basin

    Science.gov (United States)

    Bauters, Marijn; Verbeeck, Hans; Cizungu, Landry; Boeckx, Pascal

    2016-04-01

    Characterization of fundamental processes in different forest types is vital to understand the interaction of forests with their changing environment. Recent data analyses, as well as modeling activities have shown that the CO2 uptake by terrestrial ecosystems strongly depends on site fertility, i.e. nutrient availability. Accurate projections of future net forest growth and terrestrial CO2 uptake thus necessitate an improved understanding on nutrient cycles and how these are coupled to the carbon (C) cycle in forests. This holds especially for tropical forests, since they represent about 40-50% of the total carbon that is stored in terrestrial vegetation, with the Amazon basin and the Congo basin being the largest two contiguous blocks. However, due to political instability and reduced accessibility in the central Africa region, there is a strong bias in scientific research towards the Amazon basin. Consequently, central African forests are poorly characterized and their role in global change interactions shows distinct knowledge gaps, which is important bottleneck for all efforts to further optimize Earth system models explicitly including this region. Research in the Congo Basin region should combine assessments of both carbon stocks and the underlying nutrient cycles which directly impact the forest productivity. We set up a monitoring network for carbon stocks and nitrogen fluxes in four different forest types in the Congo Basin, which is now operative. With the preliminary data, we can get a glimpse of the differences in nitrogen budget and biogeochemistry of African mixed lowland rainforest, monodominant lowland forest, mixed montane forest and eucalypt plantations.

  5. Diazotroph Diversity in the Sea Ice, Melt Ponds, and Surface Waters of the Eurasian Basin of the Central Arctic Ocean.

    Science.gov (United States)

    Fernández-Méndez, Mar; Turk-Kubo, Kendra A; Buttigieg, Pier L; Rapp, Josephine Z; Krumpen, Thomas; Zehr, Jonathan P; Boetius, Antje

    2016-01-01

    The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which encodes the iron protein of the nitrogenase enzyme. We amplified 529 nifH sequences from 26 samples of Arctic melt ponds, sea ice and surface waters. These sequences resolved into 43 clusters at 92% amino acid sequence identity, most of which were non-cyanobacterial phylotypes from sea ice and water samples. One cyanobacterial phylotype related to Nodularia sp. was retrieved from sea ice, suggesting that this important functional group is rare in the Central Arctic Ocean. The diazotrophic community in sea-ice environments appear distinct from other cold-adapted diazotrophic communities, such as those present in the coastal Canadian Arctic, the Arctic tundra and glacial Antarctic lakes. Molecular fingerprinting of nifH and the intergenic spacer region of the rRNA operon revealed differences between the communities from river-influenced Laptev Sea waters and those from ice-related environments pointing toward a marine origin for sea-ice diazotrophs. Our results provide the first record of diazotrophs in the Central Arctic and suggest that microbial nitrogen fixation may occur north of 77°N. To assess the significance of nitrogen fixation for the nitrogen budget of the Arctic Ocean and to identify the active nitrogen fixers, further biogeochemical and molecular biological studies are needed.

  6. Diazotroph diversity in the sea ice, melt ponds and surface waters of the Eurasian Basin of the Central Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Mar Fernández-Méndez

    2016-11-01

    Full Text Available The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which encodes the iron protein of the nitrogenase enzyme. We amplified 529 nifH sequences from 26 samples of Arctic melt ponds, sea ice and surface waters. These sequences resolved into 43 clusters at 92% amino acid sequence identity, most of which were non-cyanobacterial phylotypes from sea ice and water samples. One cyanobacterial phylotype related to Nodularia sp. was retrieved from sea ice, suggesting that this important functional group is rare in the Central Arctic Ocean. The diazotrophic community in sea-ice environments appear distinct from other cold-adapted diazotrophic communities, such as those present in the coastal Canadian Arctic, the Arctic tundra and glacial Antarctic lakes. Molecular fingerprinting of nifH and the intergenic spacer region of the rRNA operon revealed differences between the communities from river-influenced Laptev Sea waters and those from ice-related environments pointing towards a marine origin for sea-ice diazotrophs. Our results provide the first record of diazotrophs in the Central Arctic and suggest that microbial nitrogen fixation may occur north of 77ºN. To assess the significance of nitrogen fixation for the nitrogen budget of the Arctic Ocean and to identify the active nitrogen fixers, further biogeochemical and molecular biological studies are needed.

  7. Diazotroph Diversity in the Sea Ice, Melt Ponds, and Surface Waters of the Eurasian Basin of the Central Arctic Ocean

    Science.gov (United States)

    Fernández-Méndez, Mar; Turk-Kubo, Kendra A.; Buttigieg, Pier L.; Rapp, Josephine Z.; Krumpen, Thomas; Zehr, Jonathan P.; Boetius, Antje

    2016-01-01

    The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which encodes the iron protein of the nitrogenase enzyme. We amplified 529 nifH sequences from 26 samples of Arctic melt ponds, sea ice and surface waters. These sequences resolved into 43 clusters at 92% amino acid sequence identity, most of which were non-cyanobacterial phylotypes from sea ice and water samples. One cyanobacterial phylotype related to Nodularia sp. was retrieved from sea ice, suggesting that this important functional group is rare in the Central Arctic Ocean. The diazotrophic community in sea-ice environments appear distinct from other cold-adapted diazotrophic communities, such as those present in the coastal Canadian Arctic, the Arctic tundra and glacial Antarctic lakes. Molecular fingerprinting of nifH and the intergenic spacer region of the rRNA operon revealed differences between the communities from river-influenced Laptev Sea waters and those from ice-related environments pointing toward a marine origin for sea-ice diazotrophs. Our results provide the first record of diazotrophs in the Central Arctic and suggest that microbial nitrogen fixation may occur north of 77°N. To assess the significance of nitrogen fixation for the nitrogen budget of the Arctic Ocean and to identify the active nitrogen fixers, further biogeochemical and molecular biological studies are needed. PMID:27933047

  8. Southern North Sea Basin in Europe: Biodiversity of the Marine Fürstenau Formation Including Early White and Megatooth Sharks

    Directory of Open Access Journals (Sweden)

    C. G. Diedrich

    2012-01-01

    Full Text Available The Fürstenau Formation (Lutetian, Paleogene, Eocene is based on type sections near Fürstenau in Germany (central Europe and is built of 22 meter thick marine glauconitic and strongly bioturbated sands, clays, and a vertebrate-rich conglomerate bed. The conglomerate layer from the Early Lutetian transgression reworked Lower Cretaceous, and Paleogene marine sediments. It is dominated by pebbles from the locally mountains which must have been transported by an ancient river in a delta fan. Marine reworked Lower Cretaceous and Paleogen pebbles/fossils, were derived from the underlying deposits of northern Germany (= southern pre North Sea basin. The benthic macrofauna is cold upwelling water influenced and non-tropical, and medium divers. The vertebrate fish fauna is extremely rich in shark teeth, with about 5,000 teeth per cubic meter of gravel. The most dominant forms are teeth from sand shark ancestors Striatolamia macrota, followed by white shark ancestors Carcharodon auriculatus. Even teeth from the magatooth shark ancestor Carcharocles sokolovi are present in a moderately diverse and condensed Paleogene fish fauna that also includes rays, chimaeras, and more then 80 different bony fish. Fragmentary turtle remains are present, and few terrestrial vertebrates and even marine mammals with phocids, sirenians and possibly whales.

  9. North Central Climate Science Center--science agenda 2012-2017

    Science.gov (United States)

    Morisette, Jeffrey T.

    2012-01-01

    The information presented here provides the five-year science agenda for the North Central Climate Science Center. It is meant to be a high-level guide that describes the spatial context of the center, the primary partners and stakeholders, and the strategic framework the center will use in applying climate science to inform management.

  10. An Inventory of Natural, Human, and Social Overhead Capital Resources in North-Central New Mexico.

    Science.gov (United States)

    Carruthers, Garrey; Eastman, Clyde

    Concerned with the north-central area of New Mexico (Rio Arriba, Taos, Colfax, Mora, Santa Fe, and San Miguel counties), this inventory describes the situation and delineation of the region, the natural resources (physical characteristics, land, land-ownership patterns, land-use patterns, land-title problems, water resources, and minerals); human…

  11. Use and breeding of forage grasses in the North Central USA

    Science.gov (United States)

    Forage grasses are used for conservation harvesting, usually hay or balage, and for grazing within the North Central region of the USA. Historically, smooth bromegrass, timothy, reed canarygrass, and orchardgrass have been important species and they still exist in many old hay fields. Tall fescue, m...

  12. A Year of Transition: North Central Regional Center for Rural Development Annual Report 2009

    Science.gov (United States)

    North Central Regional Center for Rural Development, 2009

    2009-01-01

    The North Central Regional Center for Rural Development (NCRCRD) is one of four centers in the United States that work to improve opportunities and quality of life in rural communities. With funding from the USDA National Institute of Food and Agriculture and the land-grant universities in its 12-state region, the NCRCRD engages Extension…

  13. Lawn Weeds and Their Control. North Central Regional Extension Publication No. 26.

    Science.gov (United States)

    Purdue Univ., Lafayette, IN. Cooperative Extension Service.

    This publication discusses lawn weed control for the twelve state north central region of the country. Written for use by homeowners, the publication focuses on weed identification and proper herbicide selection and application. Identification of weeds and safe and appropriate herbicide use are emphasized. Forty-six weed and turf plants are…

  14. Predictors of Successful Nursing Education Outcomes: A Study of the North Carolina Central University's Nursing Program

    Science.gov (United States)

    Ukpabi, Chinasa Victor

    2008-01-01

    The primary purpose of this study was to specify the variables that would play the greatest role in predicting success of North Carolina Central University (NCCU) nursing graduates in the National Certification Licensure Examination for Registered Nurses (NCLEX-RN). Participants for this study include a convenience sample of 39 students who…

  15. North Central Region 4-H Volunteers: Documenting Their Contributions and Volunteer Development

    Science.gov (United States)

    Nippolt, Pamela Larson; Pleskac, Sue; Schwartz, Vicki; Swanson, Doug

    2012-01-01

    Documenting volunteer contributions strengthens Extension partnerships with volunteers. A team of North Central Region 4-H volunteer specialists collaborated to conduct a study of 4-H volunteer contributions and impacts related to working with youth within the 4-H program. Over three thousand (3,332) 4-H volunteers from throughout the 12-state…

  16. Stratigraphical and structural setting of the Palaeogene siliciclastic sediments in the Dutch part of the North Sea Basin

    NARCIS (Netherlands)

    Lugt, I.R. de

    2007-01-01

    In this thesis, a detailed tectonic and stratigraphic reconstruction of the development of the southern part of the Late Palaeocene - Oligocene Dutch North Sea Basin is presented. The research concentrates on fault geometry and sedimentary architecture in response to tectonic activity. The aim of th

  17. Georesistivity structure in the central part of North-Eastern Japan Arc; Tohoku chiho chubu chiiki no denki dendodo kozo

    Energy Technology Data Exchange (ETDEWEB)

    Fujinawa, Y. [National Research Institute for Disaster Prevention, Tsukuba (Japan); Kawakami, N. [GERD Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan); Ueshima, M. [The University of Tokyo, Tokyo (Japan). Earthquake Research Institute; Honkura, Y. [Tokyo Institute of Technology, Tokyo (Japan)

    1998-03-13

    MT measurement of transects was made in the central part of North-Eastern Japan Arc to clarify tectonics of subduction zones. 1-D, 2-D and 3-D resistivity structures are observed in surface layers, and zones shallower and deeper than a Conrad surface, respectively. A main structure direction is S-N or NNE-SSW. Ishinomaki-Chokai tectonic line and low- resistivity zones due to Quaternary volcanos (Naruko, Onikobe) exist in a backbone range region. Resistivity is 100{Omega}{center_dot}m or less by Bostick Inversion except Mesozoic and Palaeozoic layers in the southern Kitakami mountainous region, resulting in a good agreement with previous results in a north transect. Resistivity is several {Omega}{center_dot}m and depth is several km around Shinjo basin and in surface layers of Kitakami River region. The backbone range region shows complex resistivity structures because of volcanic activity and wide-area hot water activity. High-resistivity layers correspond to stable Mesozoic and Palaeozoic land layers. Seismic velocity increases in the low-resistivity zone. Earthquake generally occurs at the boundary between resistivity structures. 68 refs., 9 figs., 2 tabs.

  18. A new age model for the early-middle Miocene in the North Alpine Foreland Basin

    Science.gov (United States)

    Reichenbacher, Bettina; Krijgsman, Wout; Pippèrr, Martina; Sant, Karin; Kirscher, Uwe

    2016-04-01

    The establishment of high-resolution age models for sedimentary successions is crucial for numerous research questions in the geosciences and related disciplines. Such models provide an absolute chronology that permits precise dating of depositional episodes and related processes such as mountain uplift or climate change. Recently, our work in the Miocene sediments of the North Alpine Foreland Basin (NAFB) has revealed a significantly younger age (16.6 Myr) for sediments that were thought to have been deposited 18 Myr ago. This implies that a fundamentally revised new age model is needed for the entire suite of lower-middle Miocene sedimentary rocks in the NAFB (20 to 15-Myr). Our new data also indicate that previously published reconstructions of early-middle Miocene palaeogeography, sedimentation dynamics, mountain uplift and climate change in the NAFB all require a critical review and revision. Further, the time-span addressed is of special interest, since it encompasses the onset of a global warming phase. However, it appears that a fundamentally revised new age model for the entire suite of lower-middle Miocene sedimentary rocks in the NAFB can only be achieved based on a 500 m deep drilling in the NAFB for which we currently seek collaboration partners to develop a grant application to the International Continental Deep Drilling Program (ICDP). Reference: Reichenbacher, B., W. Krijgsman, Y. Lataster, M. Pippèrr, C. G. C. Van Baak, L. Chang, D. Kälin, J. Jost, G. Doppler, D. Jung, J. Prieto, H. Abdul Aziz, M. Böhme, J. Garnish, U. Kirscher, and V. Bachtadse. 2013. A new magnetostratigraphic framework for the Lower Miocene (Burdigalian/Ottnangian, Karpatian) in the North Alpine Foreland Basin. Swiss Journal of Geosciences 106:309-334.

  19. Study on relationship between deep and shallow structures along north boundary fault of Yanqing-Fanshan basin

    Institute of Scientific and Technical Information of China (English)

    于贵华; 徐锡伟; 朱艾澜; 马文涛; 刁桂苓; 张四昌; 张先康; 刘保金; 孙振国

    2004-01-01

    Based on the results of surface geology, shallow and deep seismic survey, features of micro-earthquake activity along the north boundary fault of Yanqing-Fanshan sub-basin and their relationship with the surface active faults and the deep-seated crustal structure are analyzed using the recordings from the high-resolution digital seismic network. The focal mechanism solutions of micro-earthquakes, whose locations are precisely determined by the seismic network, have confirmed the structural characteristics to be the rotational planar normal fault and demonstrated the surface traces of the north boundary fault of Yanqing-Fanshan sub-basin. By using the digital recordings of earthquakes with the high resolutions and analyzing the mechanism solutions, our study has revealed the relationship between the geological phenomena in the shallow and deep structures in Yanqing-Huailai basin and the transition features from the brittle to ductile deformation with the crustal depth.

  20. TRANSGRESSIVE SEQUENCES ON FORELAND MARGINS: A CASE STUDY OF THE NEOGENE CENTRAL GUADALQUIVIR BASIN, SOUTHERN SPAIN

    Directory of Open Access Journals (Sweden)

    J. GABRIEL PENDÓN

    2004-07-01

    Full Text Available The Guadalquivir foreland basin, located between the Iberian basement northward and the Betic orogen to the South, represents the western sector of the earlier foredeep basin of the Betic Cordillera. Along the northern foreland margin, the sedimentary fill of this basin includes a Tortonian Basal Transgressive Complex (BTC, composed of five internal sequences bounded by transgressive surfaces. Two main parts are distinguished within each sequence: the lower transgressive lag deposits, and the upper stillstand/prograding sediments. Three facies associations were distinguished within this stratigraphic succession along the central sector of this basin margin: unfossiliferous conglomerates and coarse-grained sands (A, fossiliferous conglomerates and coarse-grained sands (B, and yellow medium-coarse-grained fossiliferous sands (C. A fourth facies association (D: blue silty marlstones and shales overlies the BTC. Deposits of alluvial sediments (facies association A and shallow-marine/foreshore sediments (facies association C, were recurrently interrupted by transgressive pulses (facies associations B and C. Every pulse is recorded by an erosional, cemented sandy-conglomerate bar with bivalves (Ostreidae, Isognomon, balanids, gastropods and other marine bioclasts; or their transgressive equivalents. The lateral facies changes in each individual sequence of the BTC are related to: (1 the influence on the northern foreland margin of the tectonic activity of the southern orogenic margin; (2 the palaeorelief formed by irregularities of the substrate which controls the sediment dispersal; and (3 the evolution stages of the sedimentary systems. 

  1. Holocene mammalian change in the central Columbia Basin of eastern Washington state, USA

    Science.gov (United States)

    Lyman, R. Lee

    2016-08-01

    Predictions of changes in the Holocene mammalian fauna of the central Columbia Basin in eastern Washington (USA) based on environmental changes are largely met. Taxonomic richness is greatest during periods of cool-moist climate. Rates of input of faunal remains to the paleozoological record may suggest greater mammalian biomass during periods of greater moisture but are difficult to interpret without data on sampling intensity in the form of volume of sediment excavated. Abundances of leporids and grazing ungulates fluctuate in concert with abundance of grass. Several biogeographic records are tantalizing but require additional study and data before being accepted as valid. Records of red fox (Vulpes vulpes) indicate this species was present in the central basin during the Holocene contrary to historic records and recent suggestions modern foxes there are escapees from fur farms. Bison (Bison bison) and bighorn sheep (Ovis canadensis) underwent diminution of body size during the Holocene. Modern efforts to conserve the Columbia Basin ecosystem are advised to consider the Holocene record as indicative of what may happen to that ecosystem in the future.

  2. Effective Stress-Porosity Relationship above and Within the Oil Window in the North Sea Basin

    Directory of Open Access Journals (Sweden)

    Kenneth S. Okiongbo

    2011-01-01

    Full Text Available This study investigates the effective stress - porosity relationship above and within the oil window in the Kimmeridge Clay Formation (KCF in the North Sea Basin (UK using effective stress and porosity determined from wireline logs and pore pressure data. Porosity was determined from an empirical porosity - sonic transit - time transform, calibrated using shale and mudstone core porosity measurements from Jurassic shales in the North Sea. Effective stress was determined from the total overburden stress and pore pressure. The total overburden stress was calculated by integration of the density log. The results show that porosity range between ~11-20% in the pre-generation zone but decreased to <5% within the oil window. Compaction coefficient ($ values above the oil window vary from ~0.08-0.09 M/Pa, but vary from ~0.05-0.06 M/Pa within the oil window implying that deeper burial and a high degree of chemical precipitation and cementation has created a stiff matrix giving rise to low $ values. The effective stress-porosity relationship above and within the oil window reflects a possible decrease in effective stress occasioned by increase in porosity in the pregeneration zone.

  3. Impact of subsurface drainage on streamflows in the Red River of the North basin

    Science.gov (United States)

    Rahman, Mohammed M.; Lin, Zhulu; Jia, Xinhua; Steele, Dean D.; DeSutter, Thomas M.

    2014-04-01

    The debate about subsurface drainage effects on streamflows has been reignited in the Red River of the North basin in North America, after a decades-long abnormally wet weather pattern in the region. Our study evaluated the applicability of the Soil and Water Assessment Tool (SWAT) in modeling subsurface drainage in a cold environment; we then employed streamflow response analyses to assess the potential impacts of the extensive subsurface drainage development in the Red River Valley (RRV) on streamflows in the Red River. The results showed that extensive subsurface drainage in the RRV would likely increase the magnitude of smaller peak flows while decreasing the magnitude of larger peak flows. Discharge reduction of large peak flows was mainly caused by reducing the flow volumes rather than increasing the time-to-peak of the hydrograph. Our analysis also suggested that extensive subsurface drainage could move more water from the watershed to the rivers in the fall season, creating more storage capacity in the soils. However, such increase in storage capacity in soils would have a negligible effect in reducing the monthly flow volumes in the following spring. The proposed method of coupling a watershed model with streamflow response analysis can be readily adopted by other researchers to evaluate the streamflow impact of land-use and climate changes around the world.

  4. Tectonic control of offshore sedimentary basins to the North and West of Ireland

    Energy Technology Data Exchange (ETDEWEB)

    Max, M.D.

    1978-07-01

    A newly compiled tectonic map of Ireland and part of the offshore area can be used to show that a pattern of rejuvenated Caledonian structures was superseded by newly imposed structures at about the time of the opening of the northern North Atlantic Ocean. There are three distinct patterns of structural control: 1. Older Caledonian structures, 2. Younger Caledonian structures, and 3. Oceanic structures. Younger structural patterns are each superimposed on older, so that locally interference patterns are developed. Each of the structural regimes has controlled sedimentation in particular zones, and where superimposition has occurred, mixed shelf-continental and oceanic sedimentation can be expected at different structural levels. One of the major control structures in and immediately off NW Ireland is the Great Glen Fault system, which has been repeatedly rejuvenated since its development in Caledonian times. Other major control structures are associated with the Porcupine Seabight, which probably developed during the initiation of the immediately adjacent North Atlantic Ocean basin. Where these structural systems intersect at the head of the Seabight, sedimentational provinces can be defined. A poorly defined E-W structural line at about 53/sup 0/ 25' across the northern part of the Seabight may reflect deep wrench faulting related to a subjacent transform. Major structures along this line would have influenced sedimentation and consequent growth structures. This line may be an eastward analogue of the Gibbs Fracture Zone against which the axial zone of quasi-oceanic or attenuated continental crust in the Porcupine Seabight could terminate. 3 figures.

  5. Sedimentary geochemistry depicts 2700 years of regional climate and land use change in the Rieti Basin, Central Italy

    Science.gov (United States)

    Archer, C.; Noble, P. J.; Mensing, S. A.; Tunno, I.; Sagnotti, L.; Florindo, F.; Cifnani, G.; Zimmerman, S. R. H.; Piovesan, G.

    2014-12-01

    A 14.4 m thick sedimentary sequence was recovered in multiple cores from Lago Lungo in the Rieti Basin, an intrapenninic extensional basin ~80 km north of Rome, Italy. This sequence provides a high-resolution record of environmental change related to climatic influence and anthropogenic landscape alteration. Pollen analyses, corroborated with historical records of land-use change, define the major shifts in forest composition and their historical context. An age model of the sequence was built using ties to regional cultigen datums and archaeomagnetic reference curves. Here we focus on sedimentologic and geochemical data (scanning XRF) from the Roman Period through the Little Ice Age (LIA). The base of the sequence (ca. 680 BCE- 1 CE) is marked by a steady increase in fine-grained detrital elements Ti, Rb, and K, and corresponding decrease in Ca, representing a transition from the unaltered system after the Romans constructed a channel that the basin. The Medieval Period (MP; 900-1350 CE) is lithologically distinct, composed of varicolored bands of alternating silt, clay, and calcareous concretions. Low counts of Ca, high detrital elements and frequent abrupt peaks in levels of the redox elements Fe and Mn indicate episodic clastic influx. Pollen data indicate that the greatest degree of deforestation and erosion occurred during the MP, supported by mean sedimentation rates of ca. 1cm/year, over twice the rate of the underlying interval. The Medieval climate was warmer and more stable, population increased, and elevations >1000 m were exploited for agriculture. The influence of the Velino River on the lake appears to increase during the MP through channel migration, increased flooding, or increased overland flow. The next transition (1350 CE) marks the start of the LIA and is coincident with the Black Plague. Historical records document a large earthquake in 1349 that severely struck Central Italy, with possible effects on the lake's depositional and hydrochemical

  6. Megascopic lithologic studies of coals in the Powder River basin in Wyoming and in adjacent basins in Wyoming and North Dakota

    Science.gov (United States)

    Trippi, Michael H.; Stricker, Gary D.; Flores, Romeo M.; Stanton, Ronald W.; Chiehowsky, Lora A.; Moore, Timothy A.

    2010-01-01

    Between 1999 and 2007, the U.S. Geological Survey (USGS) investigated coalbed methane (CBM) resources in the Wyoming portion of the Powder River Basin. The study also included the CBM resources in the North Dakota portion of the Williston Basin of North Dakota and the Wyoming portion of the Green River Basin of Wyoming. This project involved the cooperation of the State Office, Reservoir Management Group (RMG) of the Bureau of Land Management (BLM) in Casper, Wyo., and 16 independent gas operators in the Powder River, Williston, and Green River Basins. The USGS and BLM entered into agreements with these CBM operators to supply samples for the USGS to analyze and provide the RMG with rapid, timely results of total gas desorbed, coal quality, and high-pressure methane adsorption isotherm data. This program resulted in the collection of 963 cored coal samples from 37 core holes. This report presents megascopic lithologic descriptive data collected from canister samples extracted from the 37 wells cored for this project.

  7. Preliminary description of hydrologic characteristics and contaminant transport potential of rocks in the Pasco Basin, south-central Washington

    Energy Technology Data Exchange (ETDEWEB)

    Deju, R.A.; Fecht, K.R.

    1979-03-01

    This report aims at consolidating existing data useful in defining the hydrologic characteristics of the Pasco Basin within south-central Washington. It also aims at compiling the properties required to evaluate contaminant transport potential within individual subsurface strata in this basin. The Pasco Basin itself is a tract of semi-arid land covering about 2,000 square miles in south-central Washington. The regional geology of this basin is dominated by tholeiitic flood basalts of the Columbia Plateau. The surface hydrology of the basin is dominated by the Yakima, Snake, and Columbia rivers. Short-lived ephemeral streams may flow for a short period of time after a heavy rainfall or snowmelt. The subsurface hydrology of the Pasco Basin is characterized by an unconfined aquifer carrying the bulk of the water discharged within the basin. This aquifer overlies a series of confined aquifers carrying progressively smaller amounts of groundwater as a function of depth. The hydraulic properties of the various aquifers and non-water-bearing strata are characterized and reported. A summary of the basic properties is tabulated. The hydrochemical data obtained are summarized. The contaminant transport properties of the rocks in the Pasco Basin are analyzed with emphasis on the dispersion and sorption coefficients and the characteristics of the potential reactions between emplaced waste and the surrounding medium. Some basic modeling considerations of the hydrogeologic systems in the basin with a brief discussion of model input requirements and their relationship to available data are presented.

  8. Age, extent and carbon storage of the central Congo Basin peatland complex.

    Science.gov (United States)

    Dargie, Greta C; Lewis, Simon L; Lawson, Ian T; Mitchard, Edward T A; Page, Susan E; Bocko, Yannick E; Ifo, Suspense A

    2017-02-02

    Peatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world's most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin. We find extensive peat deposits beneath the swamp forest vegetation (peat defined as material with an organic matter content of at least 65 per cent to a depth of at least 0.3 metres). Radiocarbon dates indicate that peat began accumulating from about 10,600 years ago, coincident with the onset of more humid conditions in central Africa at the beginning of the Holocene. The peatlands occupy large interfluvial basins, and seem to be largely rain-fed and ombrotrophic-like (of low nutrient status) systems. Although the peat layer is relatively shallow (with a maximum depth of 5.9 metres and a median depth of 2.0 metres), by combining in situ and remotely sensed data, we estimate the area of peat to be approximately 145,500 square kilometres (95 per cent confidence interval of 131,900-156,400 square kilometres), making the Cuvette Centrale the most extensive peatland complex in the tropics. This area is more than five times the maximum possible area reported for the Congo Basin in a recent synthesis of pantropical peat extent. We estimate that the peatlands store approximately 30.6 petagrams (30.6 × 10(15) grams) of carbon belowground (95 per cent confidence interval of 6.3-46.8 petagrams of carbon)-a quantity that is similar to the above-ground carbon stocks of the tropical forests of the entire Congo Basin. Our result for the Cuvette Centrale increases the best estimate of global tropical peatland carbon stocks by

  9. Age, extent and carbon storage of the central Congo Basin peatland complex

    Science.gov (United States)

    Dargie, Greta C.; Lewis, Simon L.; Lawson, Ian T.; Mitchard, Edward T. A.; Page, Susan E.; Bocko, Yannick E.; Ifo, Suspense A.

    2017-01-01

    Peatlands are carbon-rich ecosystems that cover just three per cent of Earth’s land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world’s most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin. We find extensive peat deposits beneath the swamp forest vegetation (peat defined as material with an organic matter content of at least 65 per cent to a depth of at least 0.3 metres). Radiocarbon dates indicate that peat began accumulating from about 10,600 years ago, coincident with the onset of more humid conditions in central Africa at the beginning of the Holocene. The peatlands occupy large interfluvial basins, and seem to be largely rain-fed and ombrotrophic-like (of low nutrient status) systems. Although the peat layer is relatively shallow (with a maximum depth of 5.9 metres and a median depth of 2.0 metres), by combining in situ and remotely sensed data, we estimate the area of peat to be approximately 145,500 square kilometres (95 per cent confidence interval of 131,900–156,400 square kilometres), making the Cuvette Centrale the most extensive peatland complex in the tropics. This area is more than five times the maximum possible area reported for the Congo Basin in a recent synthesis of pantropical peat extent. We estimate that the peatlands store approximately 30.6 petagrams (30.6 × 1015 grams) of carbon belowground (95 per cent confidence interval of 6.3–46.8 petagrams of carbon)—a quantity that is similar to the above-ground carbon stocks of the tropical forests of the entire Congo Basin. Our result for the Cuvette Centrale increases the best estimate of global tropical peatland carbon

  10. Watcr Security Situation in Haihc Rivcr Basin after South-to-North Watcr Transfer Project

    Institute of Scientific and Technical Information of China (English)

    JIA Shaofeng; YAN Tingting; LUE Aifeng

    2012-01-01

    The over-exploitation of water resources in the Haihe River Basin (HRB) has now become a serious problem. This is clearly evidenced by the fact that many local rivers and lakes are drying up and the total amount of over-exploited groundwater has reached over 1000×10^8m^3. It is important to note that the exploitation of water resources in HRB was reasonable before 1979. After 1980, however, over-exploitation happened with an annual average amount of 40×10^8m^3. Both the dry season and rapid economic growth in HRB took place at the same time. Therefore, the over-exploitation of water in HRB was actually the negative result of the conjunction of a continuous dry season and rapid economic growth. So the over-exploitation would not be as serious as it is today if either of the above two stopped. After the first stage of south-to-north water transfer project, the water shortage problem in HRB could be eased for the following reasons: firstly, water transfer project will bring to the Basin 60x108m3 water resources; secondly, a wet season will come back eventually according to natural law of climate variability; finally, its agricultural and industrial use and total water consumption all have decreased from the peak value, so that the groundwater table will raise certainly and ecological water in rivers and lakes that were dried-up will be partly restored. In the future, the main problem of water resources security in HRB will include water pollution, operation risk of the south-to-north water transfer project, groundwater pollution and engineering geological hazards that may be brought by groundwater rise. The proposed countermeasures are as follows: keeping strengthening water demand management, raising water price as well as subsidies for the low- income family and improving other water related policies, preventing and dealing with water pollution seriously and getting fully prepared for the operation of south-to-north water transfer project.

  11. Compositional heterogeneity of central peaks within the South Pole-Aitken Basin

    Science.gov (United States)

    Moriarty, D. P.; Pieters, C. M.; Isaacson, P. J.

    2013-11-01

    high-spectral and -spatial resolution Moon Mineralogy Mapper data, we investigate compositional variations across the central peak structures of four impact craters within the South Pole-Aitken Basin (SPA). Two distinct causes of spectral diversity are observed. Spectral variations across the central peaks of Bhabha, Finsen, and Lyman are dominated by soil development, including the effects of space weathering and mixing with local materials. For these craters, the central peak structure is homogeneous in composition, although small compositional differences between the craters are observed. This group of craters is located within the estimated transient cavity of SPA, and their central uplifts exhibit similar mafic abundances. Therefore, it is plausible that they have all uplifted material associated with melts of the lower crust or upper mantle produced during the SPA impact. Compositional differences observed between the peaks of these craters reflect heterogeneities in the SPA subsurface, although the origin of this heterogeneity is uncertain. In contrast to these craters, Leeuwenhoek exhibits compositional heterogeneity across its central peak structure. The peak is areally dominated by feldspathic materials, interspersed with several smaller exposures exhibiting a mafic spectral signature. Leeuwenhoek is the largest crater included in the study and is located in a region of complex stratigraphy involving both crustal (feldspathic) and SPA (mafic melt and ejecta) materials. The compositional diversity observed in Leeuwenhoek's central peak indicates that kilometer-scale heterogeneities persist to depths of more than 10 km in this region.

  12. Nutrients, suspended sediment, and pesticides in streams in the Red River of the North basin, Minnesota, North Dakota, and South Dakota, 1993-95

    Science.gov (United States)

    Tornes, L.H.; Brigham, M.E.; Lorenz, D.L.

    1997-01-01

    Fifteen stream sites in the Red River of the North Basin were sampled during 1993-95 to assess levels of nutrients, organic carbon, and suspended sediment, and five sites were sampled for pesticides. Concentrations varied seasonally and were related to periods of fertilizer and pesticide application, and to runoff. Concentrations of several constituents were related to the physiographic area the stream drains, but other factors such as local land use frequently complicated that relation.

  13. Long term spatial and temporal rainfall trends and homogeneity analysis in Wainganga basin, Central India

    Directory of Open Access Journals (Sweden)

    Arun Kumar Taxak

    2014-08-01

    Full Text Available Gridded rainfall data of 0.5×0.5° resolution (CRU TS 3.21 was analysed to study long term spatial and temporal trends on annual and seasonal scales in Wainganga river basin located in Central India during 1901–2012. After testing the presence of autocorrelation, Mann–Kendall (Modified Mann–Kendall test was applied to non-auto correlated (auto correlated series to detect the trends in rainfall data. Theil and Sen׳s slope estimator test was used for finding the magnitude of change over a time period. For detecting the most probable change year, Pettitt–Mann–Whitney test was applied. The Rainfall series was then divided into two partial duration series for finding changes in trends before and after the change year. Arc GIS was used to explore spatial patterns of the trends over the entire basin. Though most of the grid points shows a decreasing trend in annual rainfall, only seven grids has a significant decreasing trend during 1901–2012. On the basis of seasonal trend analysis, non-significant increasing trend is observed only in post monsoon season while seven grid points show significant decreasing trend in monsoon rainfall and non-significant in pre-monsoon and winter rainfall over the last 112 years. During the study period, overall a 8.45% decrease in annual rainfall is estimated. The most probable year of change was found to be 1948 in annual and monsoonal rainfall. There is an increasing rainfall trend in the basin during the period 1901–1948, which is reversed during the period 1949–2012 resulting in decreasing rainfall trend in the basin. Homogeneous trends in annual and seasonal rainfall over a grid points is exhibited in the basin by van Belle and Hughes׳ homogeneity trend test.

  14. The central Vienna Basin Transfer Fault - lack of knowledge or seismic gap?

    Science.gov (United States)

    Hintersberger, E.; Decker, K.

    2012-12-01

    The Vienna Pull-Apart Basin between the Alps and the Carpathians is characterized by a moderate level of historical seismicity (Imax/Mmax = 8/5.2) focused along the NNE-SSW striking left-lateral Vienna Basin Transfer Fault (VBTF) that delimits the basin towards the east. Displacement rates determined from GPS geodesy and geological markers range between 1.5 - 2.0 mm/a. However, seismic slip rates calculated from cumulative scalar seismic moments for different segments along the fault are quite heterogeneous, varying from 0.5-1.1 mm/a at the southern and northern tips to an apparently seismically totally locked segment in the central part of the basin, the so-called Lassee segment, close to the city of Vienna. Only two small earthquakes in the M3 to M4 range have been observed along this segment, in contrast to geomorphic and subsurface geophysical data that indicate that this fault segment has sustained horizontal Quaternary displacements of several tens of meters, generated by several subfaults associated with a negative flower structure. The seismic potential of this segment, which is the closest to both the Austrian capital of Vienna and the Slovak capital Bratislava, is therefore one of the key questions for the seismic hazard for those cities. Our new data from a paleoseismological trench at the Lassee segment of the VBTF is located at the tectonically controlled western margin of a Pleistocene Danube terrace (200-300 ka). Here, the VBTF has produced a ~ 25 m high scarp. The main fault within the trench displaces the coarse Pleistocene gravels and intercalated sand lenses, whose layering dips towards the fault and against the direction of flow, based on paleo-current indicators. In addition, several smaller faults are observed to have vertical displacements of up to 0.5 m. The hanging wall consists of colluvial sediments and sandy layers from extreme flooding events. As a preliminary result, at least three different colluvial wedges can be distinguished at the

  15. Linking carbon storage with functional diversity in tropical rainforest in the central Congo Basin

    Science.gov (United States)

    Verbeeck, Hans; Kearsley, Elizabeth; Bauters, Marijn; Beeckman, Hans; Huygens, Dries; Steppe, Kathy; Boeckx, Pascal

    2015-04-01

    This presentation will show an overview of results of the COBIMFO project (Congo basin integrated monitoring for forest carbon mitigation and biodiversity). In the framework of this project we have established 21 permanent 1 ha sampling plots in different forest types in the Yangambi reserve. This UNESCO Man and Biosphere reserve has an area of more than 6000 km² and is located in the heart of the Congo Basin near the Yangambi research station (DR Congo). Analysis of the inventory data of these plots revealed that carbon stocks in mature forests in this area of the Congo Basin are significantly lower (24%) than stocks recorded in the outer regions of the basin. These lower stocks are attributed to a lower maximal tree height (Kearsley et al. 2013). In addition to the carbon inventories we collected leaf and wood samples on all species within 95% basal area of each of the Yangambi plots. A total of 995 individuals were sampled, covering 123 tree species. On the samples we measured 15 traits related to leaf and wood morphology and functioning. In the presented study, relationships between the observed functional diversity and biomass are analysed. One of the remarkable results of our analysis is that species with a high functional distinctiveness have a low contribution to the basal area and the carbon stocks. In contrast, species with a high contribution to the carbon stock have a low contribution to the functional diversity. Similar patterns have been observed elsewhere (e.g. Amazon basin), but are now for the first time confirmed for central African rainforest. Finally, we also present the first results of an analysis of carbons stocks and functional diversity in tropical plantations from a unique 70-years old tree diversity experiment that was established during the colonial period at the Yangambi research station. Kearsley, E., de Haulleville, T., Hufkens, K., Kidimbu, A., Toirambe, B., Baert, G., Huygens, D., Kebede, Y., Defourny, P., Bogaert, J., Beeckman, H

  16. Origin and time-space distribution of hydrothermal systems in east-central Australian sedimentary basins: Constraints from illite geochronology and isotope geochemistry.

    Science.gov (United States)

    Uysal, I. Tonguç

    2016-04-01

    Some well-known precious mineral deposits and hydrocarbon resources occur extensively in east-central Australian sedimentary Basins. The metal occurrences are abundant in northwestern and eastern part of Queensland, whereas no significant deposits are known in large areas further south, which may, however, be hidden beneath the Jurassic-Cretaceous sedimentary basins. Important hydrocarbon resources exist within the Jurassic-Cretaceous sedimentary rocks at relatively shallow depths, of which the distribution represent zones of high paleo-geothermal gradients. This study examines the time-space distribution in relation to the regional tectonic history of concealed metal deposits and areas of high paleo-geothermal gradient leading to hydrocarbon maturation. To this end, authigenic illitic clay minerals representing various locations and stratigraphic depths in east-central Australia were investigated, of which the Rb-Sr and Ar-Ar geochronology and stable isotope geochemistry assist in delineating zones of hydrothermal systems responsible for hydro-carbon maturation/migration and potentially ore deposition. The Late Carboniferous - Early Permian crustal extension that affected large areas of eastern Australia and led to the epithermal mineralisations (e.g., the Drummond Basin) is also recorded in northern South Australia and southwest Queensland. A Late Triassic - Early Jurassic tectonic event being responsible for coal maturation and gas generation in the Bowen Basin and the epithermal mineralisation in the North Arm goldfield in SE Queensland likewise affected the areas much further west in Queensland. Some illites from the basement in outback Queensland and fault gouges from the Demon Fault in NE New South Wales yield younger Rb-Sr and Ar-Ar ages indicating the effect of hydrothermal processes as a result of a Middle-Upper Jurassic tectonic event. The majority of illite samples from the crystalline basement rocks, Permian Cooper Basin, and Jurassic

  17. Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2015

    Science.gov (United States)

    Beman, Joseph E.; Bryant, Christina F.

    2016-10-27

    The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is hydrologically defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift between San Acacia to the south and Cochiti Lake to the north. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when the Albuquerque Bernalillo County Water Utility Authority (ABCWUA) began treatment and distribution of surface water from the Rio Grande through the San Juan-Chama Drinking Water Project. A 20-percent population increase in the basin from 1990 to 2000 and a 22-percent population increase from 2000 to 2010 may have resulted in an increased demand for water in areas within the basin.An initial network of wells was established by the U.S. Geological Survey (USGS) in cooperation with the City of Albuquerque from April 1982 through September 1983 to monitor changes in groundwater levels throughout the Albuquerque Basin. In 1983, this network consisted of 6 wells with analog-to-digital recorders and 27 wells where water levels were measured monthly. The network currently (2015) consists of 124 wells and piezometers. (A piezometer is a specialized well open to a specific depth in the aquifer, often of small diameter and nested with other piezometers open to different depths.) The USGS, in cooperation with the ABCWUA, currently (2015) measures and reports water levels from the 124 wells and piezometers in the network; this report presents water-level data collected by USGS personnel at those 124 sites through water year 2015 (October 1, 2014, through September 30, 2015).

  18. BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard

    2005-08-01

    The principal research effort for Year 3 of the project is basin modeling and petroleum system identification, comparative basin evaluation and resource assessment. In the first six (6) months of Year 3, the research focus is on basin modeling and petroleum system identification and the remainder of the year the emphasis is on the comparative basin evaluation and resource assessment. No major problems have been encountered to date, and the project is on schedule.

  19. The nonmarine Lower Cretaceous of the North American Western Interior foreland basin: New biostratigraphic results from ostracod correlations and early mammals, and their implications for paleontology and geology of the basin—An overview

    Science.gov (United States)

    Sames, Benjamin; Cifelli, Richard L.; Schudack, Michael E.

    2010-08-01

    The timespan represented by the hiatus between nonmarine Upper Jurassic (Early Berriasian?) and unconformably overlying Lower Cretaceous deposits throughout the North American Western Interior foreland basin has been under discussion for the entire 20th century and remains controversial to date. Ongoing research in revision of Early Cretaceous nonmarine ostracods of some respective North American formations leads to a breakthrough concerning the verification of their biostratigraphic utility as well as their subsequent application. These ostracods are not as endemic as hitherto believed and can be used for supraregional and regional correlation, as well as improvement of the age determination of North American units. New results strongly suggest a maximum age of Late Berriasian to Valanginian (˜ 142-138 Ma) for the lower part of the Lakota (Black Hills area, South Dakota) and Cedar Mountain (Utah) formations. A pre-Aptian maximum age for the Lakota Formation is supported by early mammals. These biostratigraphic results affect the correlatable formations as well, and therefore have broad implications on basin-related geologic and paleontologic topics that are overviewed and discussed herein. The central issue hampering an integrated synthesis of the foreland basin is its yet imprecise chronostratigraphic framework and documentation. Temporal relationships between the gologic processes of the basin and their control factors are still insufficiently calibrated or controversial. Detailed ongoing revision of North American Early Cretaceous nonmarine ostracods demonstrates their applicability, utility, and further potential as tool for improvement of the chronostratigraphy of the Western Interior foreland basin at both small and large scales. These ostracods also foster understanding of animal (e.g. early mammals and dinosaurs) and plant (angiosperms) evolution on the North American continent and show promise of providing age determinations for single-sample horizons in

  20. A Plan for Continuing Education in Nursing in Five North Central States (Michigan, Minnesota, Montana, North Dakota, and Wisconsin): A Proposal for Discussion and Action.

    Science.gov (United States)

    Cooper, Signe W.; Byrns, Helene Hestad

    The purpose of the paper is to provide recommendations and suggest approaches for the coordination of continuing education in the North Central States of Michigan, Minnesota, Montana, North Dakota, and Wisconsin. The document is directed to non-credit continuing education exclusively and does not consider inservice education within its scope.…

  1. INTEGRATING GEOPHYSICS, GEOLOGY, AND HYDROLOGY TO DETERMINE BEDROCK GEOMETRY CONTROLS ON THE ORIGIN OF ISOLATED MEADOW COMPLEXES WITHIN THE CENTRAL GREAT BASIN, NEVADA

    Science.gov (United States)

    Riparian meadow complexes found in mountain ranges of the Central Great Basin physiographic region (western United States) are of interest to researchers as they contain significant biodiversity relative to the surrounding basin areas. These meadow complexes are currently degradi...

  2. Gas Source Research of the Central Gasfield in Shaan-Gan-Ning Basin

    Institute of Scientific and Technical Information of China (English)

    Pei Xigu

    1995-01-01

    @@ The major producing formation of the Central Gasfield in ShaanGan-Ning Basin is a reservoir of weathered crust carbonate rock in the top of Ordovician, which lies below a Caledonian unconformable contact. Above the unconformable contact a set of coal-measure hydrocarbon source rock having strong ability of generation exists with contintentaloffshore interaction at Carboniferous-Permian stage.While below it, there is a set of hydrocarbon source rock of marine carbonate facies. Between them,there is accumulation in weathered crust of the top of Ordovician, making one of the focuses for common concerned that, from which stratum the gas does generate.

  3. Updated precipitation reconstruction (AD 1482-2012) for Huashan, north-central China

    Science.gov (United States)

    Chen, Feng; Zhang, Ruibo; Wang, Huiqin; Qin, Li; Yuan, Yujiang

    2016-02-01

    We developed a tree-ring width chronology from pine trees ( Pinus tabulaeformis and Pinus armandii) stand near the peaks of Huashan, Shaanxi, north-central China. Growth-climate response analyses showed that the radial growth of pine trees is mainly influenced by April-June precipitation. A model to reconstruct precipitation based on tree widths was constructed, accounting for 55 % of the instrumental variance during the period 1953-2012. Spatial correlation analyses between the reconstruction and observed gridded precipitation data shows that the seasonal precipitation reconstruction captures regional climatic variations over north China. Compared with the historical archives and other tree-ring records in north China, many large-scale drought events, linked to the El Niño-Southern Oscillation (ENSO), were found. Many of these events have had profound impacts on the people of north China over the past several centuries. Composite maps of sea surface temperatures and 500 hPa geopotential heights for selected extremely dry and wet years in Huashan show characteristics similar to those related to the ENSO patterns, particularly with regard to ocean and atmospheric conditions in the equatorial and north Pacific. Our 531-year precipitation reconstruction for Huashan provides a long-term perspective on current and 20th century wet and dry events in north China, and is useful to guide expectations of future variability, and helps us to address climate change.

  4. Sedimentary response to orogenic exhumation in the northern rocky mountain basin and range province, flint creek basin, west-central Montana

    Science.gov (United States)

    Portner, R.A.; Hendrix, M.S.; Stalker, J.C.; Miggins, D.P.; Sheriff, S.D.

    2011-01-01

    Middle Eocene through Upper Miocene sedimentary and volcanic rocks of the Flint Creek basin in western Montana accumulated during a period of significant paleoclimatic change and extension across the northern Rocky Mountain Basin and Range province. Gravity modelling, borehole data, and geologic mapping from the Flint Creek basin indicate that subsidence was focused along an extensionally reactivated Sevier thrust fault, which accommodated up to 800 m of basin fill while relaying stress between the dextral transtensional Lewis and Clark lineament to the north and the Anaconda core complex to the south. Northwesterly paleocurrent indicators, foliated metamorphic lithics, 64 Ma (40Ar/39Ar) muscovite grains, and 76 Ma (U-Pb) zircons in a ca. 27 Ma arkosic sandstone are consistent with Oligocene exhumation and erosion of the Anaconda core complex. The core complex and volcanic and magmatic rocks in its hangingwall created an important drainage divide during the Paleogene shedding detritus to the NNW and ESE. Following a major period of Early Miocene tectonism and erosion, regional drainage networks were reorganized such that paleoflow in the Flint Creek basin flowed east into an internally drained saline lake system. Renewed tectonism during Middle to Late Miocene time reestablished a west-directed drainage that is recorded by fluvial strata within a Late Miocene paleovalley. These tectonic reorganizations and associated drainage divide explain observed discrepancies in provenance studies across the province. Regional correlation of unconformities and lithofacies mapping in the Flint Creek basin suggest that localized tectonism and relative base level fluctuations controlled lithostratigraphic architecture.

  5. Status and Understanding of Groundwater Quality in the Central-Eastside San Joaquin Basin, 2006: California GAMA Priority Basin Project

    Science.gov (United States)

    Landon, Matthew K.; Belitz, Kenneth; Jurgens, Bryant C.; Justin T. Kulongoski, Justin T.; Johnson, Tyler D.

    2010-01-01

    Groundwater quality in the approximately 1,695-square-mile Central Eastside San Joaquin Basin (Central Eastside) study unit was investigated as part of the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA PBP was developed in response to the California Groundwater Quality Monitoring Act of 2001, and is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey and the Lawrence Livermore National Laboratory. The GAMA Central Eastside study unit was designed to provide a spatially unbiased assessment of untreated-groundwater quality, as well as a statistically consistent basis for comparing water quality throughout California. During March through June 2006, samples were collected from 78 wells in Stanislaus and Merced Counties, 58 of which were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells), and 20 of which were sampled to evaluate changes in water chemistry along groundwater-flow paths (understanding wells). Water-quality data from the California Department of Public Health (CDPH) database also were used for the assessment. An assessment of the current status of the groundwater quality included collecting samples from wells for analysis of anthropogenic constituents such as volatile organic compounds (VOCs) and pesticides, as well as naturally occurring constituents such as major ions and trace elements. The assessment of status is intended to characterize the quality of untreated-groundwater resources within the primary aquifer system, not the treated drinking water delivered to consumers by water purveyors. The primary aquifer system (hereinafter, primary aquifer) is defined as that part of the aquifer corresponding to the perforation interval of wells listed in the CDPH database for the Central Eastside study unit. The quality of groundwater in shallower or

  6. Body wave attenuation characteristics in the crust of Alborz region and North Central Iran

    Science.gov (United States)

    Farrokhi, M.; Hamzehloo, H.

    2016-11-01

    Attenuation of P and S waves has been investigated in Alborz and north central part of Iran using the data recorded by two permanent and one temporary networks during October 20, 2009, to December 22, 2010. The dataset consists of 14,000 waveforms from 380 local earthquakes (2 Iran, respectively. These relations for Q S for Alborz region and North Central Iran have estimated as (83 ± 8)f (0.99 ± 0.07) and (68 ± 5)f (0.96 ± 0.05), respectively. The observed low Q values could be the results of thermoelastic effects and/or existing fracture. The estimated frequency-dependent relationships are comparable with tectonically active regions.

  7. Late Pleistocene to Holocene alluvial tableland formation in an intra-mountainous basin in a tectonically active mountain belt - A case study in the Puli Basin, central Taiwan

    NARCIS (Netherlands)

    Tseng, Chia Han; Lüthgens, Christopher; Tsukamoto, Sumiko; Reimann, Tony; Frechen, Manfred; Böse, Margot

    2016-01-01

    The morphology in Taiwan is a product of high tectonic activity at the convergent margin and East Asian monsoon climate. Tablelands are prominent geomorphic features in the Puli Basin in central Taiwan. These tablelands provide an archive to understand links between past climatic evolution and te

  8. Water-quality assessment of the Central Arizona Basins, Arizona and northern Mexico; environmental setting and overview of water quality

    Science.gov (United States)

    Cordy, Gail E.; Rees, Julie A.; Edmonds, Robert J.; Gebler, Joseph B.; Wirt, Laurie; Gellenbeck, Dorinda J.; Anning, David W.

    1998-01-01

    The Central Arizona Basins study area in central and southern Arizona and northern Mexico is one of 60 study units that are part of the U.S. Geological Survey's National Water-Quality Assessment program. The purpose of this report is to describe the physical, chemical, and environmental characteristics that may affect water quality in the Central Arizona Basins study area and present an overview of water quality. Covering 34,700 square miles, the study area is characterized by generally north to northwestward-trending mountain ranges separated by broad, gently sloping alluvial valleys. Most of the perennial rivers and streams are in the northern part of the study area. Rivers and streams in the south are predominantly intermittent or ephemeral and flow in response to precipitation such as summer thunderstorms. Effluent-dependent streams do provide perennial flow in some reaches. The major aquifers in the study area are in the basin-fill deposits that may be as much as 12,000 feet thick. The 1990 population in the study area was about 3.45 million, and about 61 percent of the total was in Maricopa County (Phoenix and surrounding cities). Extensive population growth over the past decade has resulted in a twofold increase in urban land areas and increased municipal water use; however, agriculture remains the major water use. Seventy-three percent of all water with drawn in the study area during 1990 was used for agricultural purposes. The largest rivers in the study area-the Gila, Salt, and Verde-are perennial near their headwaters but become intermittent downstream because of impoundments and artificial diversions. As a result, the Central Arizona Basins study area is unique compared to less arid basins because the mean surface-water outflow is only 528 cubic feet per second from a total drainage area of 49,650 square miles. Peak flows in the northern part of the study area are the result of snowmelt runoff; whereas, summer thunderstorms account for the peak flows in

  9. Ethiopian Central Rift Valley basin hydrologic modelling using HEC-HMS and ArcSWAT

    Science.gov (United States)

    Pascual-Ferrer, Jordi; Candela, Lucila; Pérez-Foguet, Agustí

    2013-04-01

    An Integrated Water Resources Management (IWRM) shall be applied to achieve a sustainable development, to increase population incomes without affecting lives of those who are highly dependent on the environment. First step should be to understand water dynamics at basin level, starting by modeling the basin water resources. For model implementation, a large number of data and parameters are required, but those are not always available, especially in some developing countries where different sources may have different data, there is lack of information on data collection, etc. The Ethiopian Central Rift Valley (CRV) is an endorheic basin covering an area of approximately 10,000 km2. For the period 1996-2005, the average annual volume of rainfall accounted for 9.1 Mm3, and evapotranspiration for 8 Mm3 (Jansen et al., 2007). From the environmental point of view, basin ecosystems are endangered due to human activities. Also, poverty is widespread all over the basin, with population mainly living from agriculture on a subsistence economy. Hence, there is an urgent need to set an IWRM, but datasets required for water dynamics simulation are not too reliable. In order to reduce uncertainty of numerical simulation, two semi-distributed open software hydrologic models were implemented: HEC-HMS and ArcSWAT. HEC-HMS was developed by the United States Army Corps of Engineers (USACoE) Hydrologic Engineering Center (HEC) to run precipitation-runoff simulations for a variety of applications in dendritic watershed systems. ArcSWAT includes the SWAT (Soil and Water Assessment Tool, Arnold et al., 1998) model developed for the USDA Agricultural Research Service into ArcGIS (ESRI®). SWAT was developed to assess the impact of land management practices on large complex watersheds with varying soils, land use and management conditions over long periods of time (Neitsch et al., 2005). According to this, ArcSWAT would be the best option for IWRM implementation in the basin. However

  10. Difference in full-filled time and its controlling factors in the Central Canyon of the Qiongdongnan Basin

    Institute of Scientific and Technical Information of China (English)

    SHANG Zhilei; XIE Xinong; LI Xushen; ZHANG Daojun; HE Yunlong; YANG Xing; CUI Mingzhe

    2015-01-01

    Based on the interpretation of high resolution 2D/3D seismic data, sedimentary filling characteristics and full-filled time of the Central Canyon in different segments in the Qiongdongnan Basin of northwestern South China Sea have been studied. The research results indicate that the initial formation age of the Central Canyon is traced back to 11.6 Ma (T40), at which the canyon began to develop due to the scouring of turbidity currents from west to east. During the period of 11.6–8.2 Ma (T40–T31), strong downcutting by gravity flow occurred, which led to the formation of the canyon. The canyon fillings began to form since 8.2 Ma (T31) and were dominated by turbidite deposits, which constituted of lateral migration and vertical superposition of turbidity channels during the time of 8.2–5.5 Ma. The interbeds of turbidity currents deposits and mass transport deposits (MTDs) were developed in the period of 5.5–3.8 Ma (T30–T28). After then, the canyon fillings were primarily made up of large scale MTDs, interrupted by small scale turbidity channels and thin pelagic mudstones. The Central Canyon can be divided into three types according to the main controlling factors, geomorphology-controlled, fault-controlled and intrusion-modified canyons. Among them, the geomorphology-controlled canyon is developed at the Ledong, Lingshui, Songnan and western Baodao Depressions, situated in a confined basin center between the northern slope and the South Uplift Belt along the Central Depression Belt. The fault-controlled canyon is developed mainly along the deep-seated faults in the Changchang Depression and eastern Baodao Depression. Intrusion-modified canyon is only occurred in the Songnan Low Uplift, which is still mainly controlled by geomorphology, the intrusion just modified seabed morphology. The full-filled time of the Central Canyon differs from west to east, displaying a tendency of being successively late eastward. The geomorphology-controlled canyon was

  11. Crater palaeolakes in the Tibesti mountains (Central Sahara, North Chad) - New insights into past Saharan climates

    Science.gov (United States)

    Kröpelin, Stefan; Dinies, Michèle; Sylvestre, Florence; Hoelzmann, Philipp

    2016-04-01

    For the first time continuous lacustrine sections were sampled from the volcanic Tibesti Mountains (Chad): In the 900 m deep crater of Trou au Natron at Pic Toussidé (3,315 m a.s.l.) and from the 800 m deep Era Kohor, the major sub-caldera of Emi Koussi (3,445 m a.s.l.). The remnant diatomites on their slopes are located 360 m (Trou au Natron) and 125 m (Era Kohor) above the present day bottom of the calderas. These sediments from highly continental positions in the central Sahara are keys for the reconstruction of the last climatic cycles (Kröpelin et al. 2015). We report first results from sedimentary-geochemical (total organic and total inorganic carbon contents; total nitrogen; major elements; mineralogy) and palynological analyses for palaeo-environmental interpretations. The diatomites from the Trou au Natron comprise 330 cm of mostly calcitic sediments with relatively low organic carbon (fern stands. Regional pollen rain-e.g. grasses and wormwood-is scarcely represented. Golden algae dominate in the lower section. The results of the first palynological samples suggest a small sedimentation basin. Two 14C-dated charcoals out of the upper part of the section indicate mid-Holocene ages and a linear extrapolation based on a sediment accumulation rate of 1.4mma-1 would lead to tentative dates of ~8650 cal a BP for basal lacustrine sediments and ~4450 cal a BP for the cessation of this lacustrine sequence. The diatomites from the Era Kohor reflect a suite of sections that in total sum up to 145 cm of mostly silica-based sediments with very low carbon contents (< 2% TC). Calcite dominated sediments are only present in the topmost 15 cm. Grasses and wormword are dominating throughout the sequence, probably reflecting the main constituents of the regional vegetation. Cattail (Typha/Sparganium) and especially milfoil (Myriophyllum) are recorded abundantly and continuously throughout the sequence. In combination with green algae like Pediastrum the first pollen

  12. Spatio-temporal competition dynamics of larch species in North Central Siberia

    OpenAIRE

    2016-01-01

    In North Central Siberia larch trees dominate huge parts of the prevailing light-coniferous taiga. In this unique ecosystem, permafrost limits the soil layer that thaws in summer and hence the supply of nutrients and water available for plants. Two larch species dominate the forest and build the tree line: Siberian larch (Larix sibirica LEDEB.) and Dahurian larch (Larix gmelinii (RUPr.) RUPR.). In changing climatic conditions, the distribution areas of both species will shift and overlap more...

  13. Regional subsidence history and 3D visualization with MATLAB of the Vienna Basin, central Europe

    Science.gov (United States)

    Lee, E.; Novotny, J.; Wagreich, M.

    2013-12-01

    This study reconstructed the subsidence history by the backstripping and 3D visualization techniques, to understand tectonic evolution of the Neogene Vienna Basin. The backstripping removes the compaction effect of sediment loading and quantifies the tectonic subsidence. The amount of decompaction was calculated by porosity-depth relationships evaluated from seismic velocity data acquired from two boreholes. About 100 wells have been investigated to quantify the subsidence history of the Vienna Basin. The wells have been sorted into 10 groups; N1-4 in the northern part, C1-4 in the central part and L1-2 in the northernmost and easternmost parts, based on their position within the same block bordered by major faults. To visualize 3D subsidence maps, the wells were arranged to a set of 3D points based on their map location (x, y) and depths (z1, z2, z3 ...). The division of the stratigraphic column and age range was arranged based on the Central Paratethys regional Stages. In this study, MATLAB, a numerical computing environment, was used to calculate the TPS interpolation function. The Thin-Plate Spline (TPS) can be employed to reconstruct a smooth surface from a set of 3D points. The basic physical model of the TPS is based on the bending behavior of a thin metal sheet that is constrained only by a sparse set of fixed points. In the Lower Miocene, 3D subsidence maps show strong evidence that the pre-Neogene basement of the Vienna Basin was subsiding along borders of the Alpine-Carpathian nappes. This subsidence event is represented by a piggy-back basin developed on top of the NW-ward moving thrust sheets. In the late Lower Miocene, Group C and N display a typical subsidence pattern for the pull-apart basin with a very high subsidence event (0.2 - 1.0 km/Ma). After the event, Group N shows remarkably decreasing subsidence, following the thin-skinned extension which was regarded as the extension model of the Vienna Basin in the literature. But the subsidence in

  14. Polyphase tectonic subsidence evolution of the Vienna Basin inferred from quantitative subsidence analysis of the northern and central parts

    Science.gov (United States)

    Lee, Eun Young; Wagreich, Michael

    2016-04-01

    The Vienna Basin is a tectonically complex Neogene basin situated at the Alpine-Carpathian transition. This study analyzes a detailed quantification of subsidence in the northern and central parts of the Vienna Basin to understand its tectonic subsidence evolution. About 200 wells were used to arrange stratigraphic setting, and wells reaching the pre-Neogene basement were analyzed for subsidence. To enhance the understanding of the regional subsidences, the wells were sorted into ten groups based on their position on major fault blocks. In the Early Miocene, subsidence was slow and along E-W to NE-SW trending axis, indicating the development of thrust-controlled piggyback basins. During the late Early Miocene data show abruptly increasing subsidence, making the initiation of the Vienna pull-apart basin system. From the Middle Miocene, the tectonic subsidence curves show regionally different patterns. The tectonic subsidence during the Middle Miocene varies laterally across the Vienna Basin, and the differential subsidence can be related to the changing tensional regime of weakening transtension and strengthening extension toward the late Middle Miocene. From the late Middle Miocene to the Late Miocene, the tectonic subsidence occurred dominantly along the regional active faults, and corresponds to the axis of E-W trending extension of the western parts of the Pannonian Basin system. In the Quaternary the Vienna Basin has been reactivated, and resulted in subsidence along the NE-SW trending Vienna Basin transfer fault system.

  15. Cenozoic Sedimentation and Tectonic Deformation in the Central Part of the Potiguar Basin

    Directory of Open Access Journals (Sweden)

    Elissandra Nascimento Moura-Lima

    2010-03-01

    Full Text Available Neogene and Quaternary sedimentary covers occur along the Brazilian coast and have been frequently describedtogether as a single unit. The study of Brazilian sedimentary basins concentrates on their rift phase, whereas the post-riftphase has been considered a tectonic quiescent period. In the Potiguar basin, although post-rift Cretaceous units are wellinvestigated, the Neogene and Quaternary sedimentary covers, as well as their identifi cation and differentiation, are still poorly known. A few previous studies have demonstrated that post-rift sedimentary units with no apparent deformation have a complexdeformation pattern in all scales of observation. The study of this deformation, however, did not include Neogene and Quaternary units.The main aim of the present study is the characterization of Neogene and Quaternary sedimentary units that outcrop in the central partof the Potiguar Basin, State of Rio Grande do Norte, Brazil, and related tectonics. The study has concentrated on the description ofthe Barreiras Formation and overlying Quaternary alluvial, marine, and aeolian deposits at 1:100,000 scale. Facies analyses, grain sizestudies, and luminescence dating were carried out. Ten informal and formal lithostratigraphic sedimentary units were described, inaddition to the Precambrian crystalline basement. The main results indicate that several Quaternary alluvial deposits were previouslymapped as the Miocene Barreiras Formation. It was possible to locate the new boundaries of the Quaternary sedimentary deposits andtheir stratigraphic relationships with older units. In addition, it was possible to identify the major fault systems in the basin that show NW- and NE-trending directions, which coincide with macro landforms. It follows that these major fault systems, mainly the NW trending system, control the deposition of Neogene and Quaternary sedimentary units.

  16. Minibasins and salt canopy in foreland fold-and-thrust belts: The central Sivas Basin, Turkey

    Science.gov (United States)

    Kergaravat, Charlie; Ribes, Charlotte; Legeay, Etienne; Callot, Jean-Paul; Kavak, Kaan Sevki; Ringenbach, Jean-Claude

    2016-06-01

    The Sivas Basin in the Central Anatolian Plateau (Turkey), which formed in the context of a foreland fold-and-thrust belt (FTB), exhibits a typical wall and basin (WAB) province characterized by symmetric minibasins separated by continuous steep-flanked walls and diapirs. Extensive fieldwork including regional and detailed local mapping of the contacts and margins of minibasins, and interpretation of a set of 2-D regional seismic lines, provide evidence for the development of a shallow evaporite level separating two generations of minibasins within the WAB province. Here beds of symmetric exposed minibasins along diapir flank are younger than minibasins observed over autochthonous evaporites. Laterally away from the WAB province, increase in wavelength of the tectonic structures suggests a deepening of the decollement level. We interpret that a shallower evaporite level developed in the form of an evaporite canopy, triggered by significant lateral shortening. The Upper Eocene-Lower Oligocene autochthonous Tuzhisar evaporite level was remobilized by the northward migrating sedimentary load and the tilting of the southern basin margin during propagation of the foreland fold-and-thrust belt. Asymmetric and symmetric primary minibasins were overrun by an allochthonous sheet forming a canopy. A second generation of salt withdrawal minibasins subsided into the allochthonous salt sheet. The polygonal pattern of the WAB province influences the growing fold-and-thrust belt system during the late stage of the secondary minibasins development. The Sivas FTB basin is the result of the interaction between fold-and-thrust belt propagation, evaporite remobilization, and interaction between evaporite flow and sedimentation in the minibasins.

  17. Central Appalachian basin natural gas database: distribution, composition, and origin of natural gases

    Science.gov (United States)

    Román Colón, Yomayra A.; Ruppert, Leslie F.

    2015-01-01

    The U.S. Geological Survey (USGS) has compiled a database consisting of three worksheets of central Appalachian basin natural gas analyses and isotopic compositions from published and unpublished sources of 1,282 gas samples from Kentucky, Maryland, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West Virginia. The database includes field and reservoir names, well and State identification number, selected geologic reservoir properties, and the composition of natural gases (methane; ethane; propane; butane, iso-butane [i-butane]; normal butane [n-butane]; iso-pentane [i-pentane]; normal pentane [n-pentane]; cyclohexane, and hexanes). In the first worksheet, location and American Petroleum Institute (API) numbers from public or published sources are provided for 1,231 of the 1,282 gas samples. A second worksheet of 186 gas samples was compiled from published sources and augmented with public location information and contains carbon, hydrogen, and nitrogen isotopic measurements of natural gas. The third worksheet is a key for all abbreviations in the database. The database can be used to better constrain the stratigraphic distribution, composition, and origin of natural gas in the central Appalachian basin.

  18. The changing climate and human vulnerability in north-central Namibia

    Directory of Open Access Journals (Sweden)

    Margaret N. Angula

    2016-01-01

    Full Text Available North-central Namibia is more vulnerable to effects of climate change and variability. Combined effects of environmental degradation, social vulnerability to poverty and a changing climate will compromise subsistence farming in north-central Namibia (NCN. This will make subsistence and small-scale farmers in the region more vulnerable to projected changes in the climate system. Thus, the aim of this article was to examine factors contributing to subsistence farmers’ vulnerability to impacts of climate change. The article further discusses different aspects of human vulnerability and existing adaptation strategies in response to impacts of climate related disasters experienced over the past three to four decades in NCN. Qualitative and quantitative research approaches and methodology were employed to obtain information from subsistence farmers in north-central Namibia. The sociodemographic characteristics of Ohangwena, Oshana and Omusati Region reveals high levels of unemployment, high adult and elderly population and high dependency on agricultural livelihood system. These indicators help understand levels of household vulnerability. The study concludes that households interviewed revealed low levels of adaptive capacity due to exposure to climate risks and combined effects of social, political and cultural factors. This article provided an understanding that is required to inform the adaptation pathways relevant for NCN.

  19. Summer variability of Saharan dust transport events in mountain areas north and south of Po basin

    Science.gov (United States)

    Landi, Tony C.; Marinoni, Angela; Cristofanelli, Paolo; Putero, Davide; Duchi, Rocco; Alborghetti, Marcello; Bonafè, Ubaldo; Calzolari, Francescopiero; Pietro Verza, Gian; Bonasoni, Paolo

    2013-04-01

    Mineral dust intrusions from northern African desert regions have a strong impact on the Mediterranean areas and Italian peninsula as they can cause an anomalous increase of aerosol concentrations in the tropospheric column and often an increase of particulate matter at ground level. The estimate of Saharan dust contribution to aerosols concentrations is therefore a key issue in air quality assessment and policy formulation, since can cause air quality exceedances of the PM10 daily limits (50 μg m-3) set by the European Union (EU/2008/50). This study presents a first identification and characterization of Saharan dust outbreaks observed during summer season at two high mountain stations located both South (Mt. Cimone, 2165 m asl) and North (Rifugio Guasti, Stelvio National Park, 3285 m asl) of Po valley. An estimation of their impact on PM10 concentrations in both sites, and in urban and rural areas of the Po basin is provided. Joining specific measurements (ground and satellite based) and numerical modeling, an investigation into the vertical structure of dust load will be presented. Actually, methodologies conceived for distinguishing dust outbreaks transported above the boundary layer without any impact at the ground level from those causing deposition are currently still lacking. Basically, the approach proposed in this work includes a deep analysis of in-situ measurements starting from long-term observation of Saharan dust carried out at the Mt. Cimone and more recent measurements performed in the framework of SHARE Stelvio Project, as well as the usage of ad hoc model chain (meteorological processor, chemical transport model, and aerosols optical properties calculation) to describe emission, transport and deposition dynamics of mineral dust that - in summertime - often affect the North Italy.

  20. Modeling the Nd isotopic composition in the North Atlantic basin using an eddy-permitting model

    Science.gov (United States)

    Arsouze, T.; Treguier, A. M.; Peronne, S.; Dutay, J.-C.; Lacan, F.; Jeandel, C.

    2010-09-01

    Boundary Exchange (BE - exchange of elements between continental margins and the open ocean) has been emphasized as a key process in the oceanic cycle of neodymium (Nd) (Lacan and Jeandel, 2005a). Here, we use a regional eddy-permitting resolution Ocean General Circulation Model (1/4°) of the North Atlantic basin to simulate the distribution of the Nd isotopic composition, considering BE as the only source. Results show good agreement with the data, confirming previous results obtained using the same parameterization of the source in a coarse resolution global model (Arsouze et al., 2007), and therefore the major control played by the BE processes in the Nd cycle on the regional scale. We quantified the exchange rate of the BE, and found that the time needed for the continental margins to significantly imprint the chemical composition of the surrounding seawater (further referred as characteristic exchange time) is of the order of 0.2 years. However, the timescale of the BE may be subject to large variations as a very short exchange time (a few days) is needed to reproduce the highly negative values of surface waters in the Labrador Sea, whereas a longer one (up to 0.5 years) is required to simulate the radiogenic influence of basaltic margins and distinguish the negative isotopic signatures of North Atlantic Deep Water from the more radiogenic southern origin water masses. This likely represents geographical variations in erosion fluxes and the subsequent particle load onto the continental margins. Although the parameterization of the BE is the same in both configurations of the model, the characteristic exchange time in the eddy-permitting configuration is significantly lower than the previous evaluations using a low resolution configuration (6 months to 10 years), but however in agreement with the available seawater Nd isotope data. This results highlights the importance of the model dynamics in simulating the BE process.

  1. Inversion tectonics in the Anayet Permian basin (Axial Zone, Central Pyrenees)

    Science.gov (United States)

    Rodriguez, L.; Cuevas, J.; Tubía, J. M.

    2012-04-01

    During Permian times the Pyrenees were characterized by extensional tectonics that opened subsident basins with pull-apart geometries. The Anayet Permian basin crops out in the western Spanish Axial Zone between the Aragon and Tena valleys. It is WNW-trending and it is filled by a continental Permian succession that represents the first post-variscan deposits in the area. Permian deposits rest discordantly over Devonian to Carboniferous limestones, sandstones and slates. In the Anayet basin, Permian deposits have been classically divided in four main detrital groups, mainly composed of sandstones and conglomerates, with three basic volcanic episodes interbedded (Gisbert, 1984, Bixel, 1987). Due to the lithological characteristics of the Permian rocks in this region, there are almost no accurate age constraints for these units. A detailed structural study of the area, including mapping and balanced cross-sections, shows increasingly older rocks to the west of the Anayet basin. Moreover, it can be deduced a mean slope of around 11 % to the west for the basin. These data confirm that the basin depocenter was located to the west and that the Anayet basin was partitioned by N10 °E-trending normal faults. Although the contacts between the Permian and the Devono-Carboniferous rocks are covered by quaternary deposits in most of its extent, a fault contact can also be recognized. The fault contact is a 3 m thick shear zone oriented N120 ° E and dipping 60° to the North. It develops breccias, fault gouges and sigmoidal S-C tectonites indicating a reverse motion. The contact places Permian slates and sandstones over Carboniferous limestones and is almost parallel to the alpine cleavage deforming Permian rocks. The slope of the contact together with the presence of younger rocks in the hangingwall of the reverse fault points out that the original contact was a normal fault reactivated as a high-angle reverse fault during the positive inversion tectonics induced by the

  2. Along-strike segmentation of the Abanico Basin, central Chile: New chronological, geochemical and structural constraints

    Science.gov (United States)

    Piquer, Jose; Hollings, Pete; Rivera, Orlando; Cooke, David R.; Baker, Michael; Testa, Francisco

    2017-01-01

    The Andes of central Chile are composed mostly of Cenozoic volcanic rocks, erupted during the opening and subsequent inversion of the intra-arc volcano-tectonic Abanico Basin. Until recently, the internal segmentation of this inverted basin was poorly understood. Based on a combination of U-Pb geochronology, (U-Th)/He thermochronology, whole rock geochemistry and structural data, we propose that the Abanico Basin can be divided into two main segments, separated by the NW-striking Piuquencillo fault and conjugate, NE-striking faults. Stratigraphic units defined in the northern segment (Abanico and Farellones formations) cannot be correlated with the rocks of the southern segment (Coya-Machali Formation and Teniente Volcanic Complex) in terms of lithofacies, depositional ages and geochemistry. The northern and southern segments also show temporal differences in their tectonic evolution. An early deformation event beginning at 22 Ma affected only the northern segment and is associated with the formation of progressive unconformities between the Abanico and Farellones formations, and also with crustal thickening as reflected in the geochemistry of the Farellones Formation. A second stage of crustal thickening and exhumation began at 12 Ma, as suggested by a sharp increase of the La/Yb ratios in the northern segment. In the southern segment, this event is reflected by only a moderate increase of La/Yb ratios, and by the transition between the Coya-Machali Formation and the Teniente Volcanic Complex. Finally, a third stage of exhumation and crustal thickening beginning at 7 Ma affected both the northern and southern segments. This last stage was the main exhumation event affecting the rocks of the Andes of central Chile, and is recorded in the geochemistry of igneous rocks by a sharp increase in the La/Yb ratios in the southern segment.

  3. Palynology, geochemistry and Re-Os age of the Lower-Middle Pennsylvanian stage boundary, central Appalachian basin, USA

    Science.gov (United States)

    Geboy, N.; Tripathy, G. R.; Ruppert, L. F.; Eble, C. F.; Blake, B. M.; Hannah, J. L.; Stein, H. J.

    2014-12-01

    The central Appalachian basin (CAB) in the eastern United States contains complicated sedimentary sequences often with thin and discontinuous strata. As an economically important coal-producing region, the basin's architectural framework and depositional history are important to understand. Typically, eustatic marine incursions, marked with black shale deposits, are used for basin-wide correlation. The Betsie Shale Member of the Kanawha Formation represents one of these relatively thick and laterally extensive marine zones. This study examines the palynoflora of the Matewan coalbed, which conformably underlies the Betsie, in the context of a new Re-Os date for the Betsie Shale Member and additional geochemical measures. At its base, the Matewan contains abundant lycopsid tree spores, indicative of a submerged, flooded paleomire. Upsection, biodiversity increases to include small fern and calamite spores as well as cordaite pollen. Combined with an observed increase of inertinite, the diversification of palynoflora suggests surficial peat exposure and drying out of the paleomire. A S-rich (28 wt. %) shaley parting separates these lower and upper benches of the Matewan and may represent an initial marine pulse prior to the glacioeustatic incursion that ultimately flooded the Matewan and deposited the overlying Betsie Shale. The Betsie is organic-rich (3.05 - 4.89 wt. % TOC) with Re and Os content ranging from 320 - 1,200 ppb and 1.5 - 5.3 ppb, respectively. The highly enriched Re values result in notably high parent:daughter ratios (187Re/188Os = 3,644 - 5,737). The Re-Os isotopic data yield a Model 1 age of 323 ± 7.8 Ma (n = 7; MSWD = 0.63) with evidence that the true age lies closer to the younger end of the uncertainty. This age is consistent with previous paleontologic-based interpretations but represents the first directly measured radiometric date for the Betsie. An absolute age for the Betsie is a critical result, as the member is correlated with units in

  4. Assessment of undiscovered oil and gas resources of the Williston Basin Province of North Dakota, Montana, and South Dakota, 2010

    Science.gov (United States)

    ,

    2011-01-01

    Using a geology-based assessment method, the U.S. Geological Survey estimated mean undiscovered volumes of 3.8 billion barrels of undiscovered oil, 3.7 trillion cubic feet of associated/dissolved natural gas, and 0.2 billion barrels of undiscovered natural gas liquids in the Williston Basin Province, North Dakota, Montana, and South Dakota. The U.S. Geological Survey (USGS) recently completed a comprehensive oil and gas assessment of the Williston Basin, which encompasses more than 90 million acres in parts of North Dakota, eastern Montana, and northern South Dakota. The assessment is based on the geologic elements of each total petroleum system (TPS) defined in the province, including hydrocarbon source rocks (source-rock maturation, hydrocarbon generation, and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). Using this geologic framework, the USGS defined 11 TPS and 19 Assessment Units (AU).

  5. Dry and wet rainy seasons in the Mantaro river basin (Central Peruvian Andes

    Directory of Open Access Journals (Sweden)

    Y. Silva

    2008-04-01

    Full Text Available Monthly precipitation data from the period of 1970 to 2004 from 38 meteorological stations in the Mantaro river basin were used to classify the rainy seasons (September–April of each year into anomalously dry or wet, and to determine the basin-wide extent of the anomalies based on the Standardized Precipitation Index (SPI. The wet periods mostly occurred in the early 1970's and during the first half of the 1980's, except for the event that occurred in the 1993/94 period which was the strongest and most generalized in the analyzed period. The dry periods occurred mostly during the second half of the 1980's and the 1990's. Consistent with this, a negative trend in precipitation of 2% per decade was found for the rainy season, due mainly to a stronger trend (−4%/decade during the peak phase (January–March.

    Despite previously reported significant negative correlations between El Niño-Southern Oscillation (ENSO and rainfall during the peak of the rainfall season, the similar amplitude variability of precipitation during the onset phase of the rainfall season (September–December, which is uncorrelated with ENSO, participate to the reduction of the absolute correlation for the full rainfall season. Correlations between rainfall in the Mantaro basin and sea surface temperature (SST in the tropical Atlantic are significant only near the end of the rainy season, with more rain associated with a weaker north-south difference in SST in the tropical Atlantic.

  6. Jurassic and Cretaceous clays of the northern and central North Sea hydrocarbon reservoirs reviewed

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, M.; Haszeldine, R.S.; Fallick, A.E.

    2006-03-15

    The principal clays of the northern and central North Sea are illite (sometimes with interlayered smectite) and kaolin. Chlorite is only locally important. Although it has been proposed that kaolin within North Sea sandstones is detrital in origin, the majority of workers have concluded that it is authigenic, largely the product of feldspar alteration. Kaolin is found within a wide range of sedimentary settings (and within shales) apparently defying the notion that kaolin is an indicator of meteoric water deposition. Within sandstones, the earliest authigenic kaolin has a vermiform morphology, the distribution of which is controlled by the availability of detrital mica to act as a nucleus, and the composition of the post-depositional porewaters. This vermiform kaolin formed in meteoric water, the presence of which is easily accounted for below sub-aerial exposure surfaces in non-marine formations, and below unconformities over marine units. In fully marine sands, and even marine shale units, kaolin still occurs. It has therefore been suggested that even these locations have been flushed with meteoric water. Early vermiform kaolin recrystallizes to a more blocky morphology as burial proceeds, at least in the Brent Group. Blocky kaolin has been reported as growing before, synchronously with, and after the formation of quartz overgrowths, though oxygen isotope studies support low-temperature growth, pre-quartz. Blocky kaolin may form during meteoric flushing associated with lower Cretaceous uplift and erosion, though it is found in fault blocks that are thought to have remained below sea level. Here, the kaolin may form in stagnant meteoric water, relics of the post-depositional porewater. It has also been proposed that the blocky kaolin grew in ascending basinal waters charged with carboxylic acids and CO{sub 2}, though this hypothesis is not supported by stable oxygen isotope data. Some of the blocky kaolin is dickite, the stable polymorph above 100{sup o}C. Fibrous

  7. Genetic and morphological divergence among Cooper's Hawk (Accipiter cooperii) populations breeding in north-central and western North America

    Science.gov (United States)

    Sonsthagen, Sarah A.; Rosenfield, Robert N.; Bielefeldt, John; Murphy, Robert K.; Stewart, Andrew C.; Stout, William C.; Driscoll, Timothy G.; Bozek, Michael A.; Sloss, Brian L.; Talbot, Sandra L.

    2012-01-01

    Cooper's Hawk (Accipiter cooperii) populations breeding in the northern portion of the species' range exhibit variation in morphological traits that conforms to predictions based on differences in prey size, tree stand density, and migratory behavior. We examined genetic structure and gene flow and compared divergence at morphological traits (PST) and genetic markers (FST) to elucidate mechanisms (selection or genetic drift) that promote morphological diversification among Cooper's Hawk populations. Cooper's Hawks appear to conform to the genetic pattern of an east-west divide. Populations in British Columbia are genetically differentiated from north-central populations (Wisconsin, Minnesota, and North Dakota; pairwise microsatellite FST= 0.031-0.050; mitochondrial DNA ΦST = 0.177-0.204), which suggests that Cooper's Hawks were restricted to at least two Pleistocene glacial refugia. The strength of the Rocky Mountains—Great Plains area as a barrier to dispersal is further supported by restricted gene-flow rates between British Columbia and other sampled breeding populations. Divergence in morphological traits (PST) was also observed across study areas, but with British Columbia and North Dakota differentiated from Wisconsin and Minnesota, a pattern not predicted on the basis of FST and ΦST interpopulation estimates. Comparison of PSTand FSTestimates suggests that heterogeneous selection may be acting on Cooper's Hawks in the northern portion of their distribution, which is consistent with hypotheses that variation in prey mass and migratory behavior among populations may be influencing overall body size and wing chord. We were unable to distinguish between the effects of genetic drift and selection on tail length in the study populations.

  8. Geomechanical Characteristics of Gas Shales: A Case Study in the North Perth Basin

    Science.gov (United States)

    Rasouli, Vamegh; Sutherland, Andrew

    2014-11-01

    Gas shales are one type of unconventional reservoirs which have attracted significant attention for gas production in recent years. Gas production from very tight shales requires employment of hydraulic fracturing as a stimulation technique. To design hydraulic fracture operation the mechanical properties of the targeted and surrounding formations should be estimated. Also, the magnitude and orientation of in situ stresses in the field need to be known to estimate the fracture initiation and propagation pressures. This study focuses on gas shale characteristics in the North Perth Basin and uses data corresponding to well Arrowsmith-2 (AS-2) which is the first dedicated shale gas well drilled in Western Australia. A log-based analysis was used to build the rock mechanical model (RMM). The RMM results were used to set up a hydraulic fracturing laboratory experiment. The test was done in the presence of three principal stresses to mimic the real field stress conditions. The test results include the pressure-time curve which was used to estimate the initiation and propagation pressure at that depth. The results were used to draw some practical conclusions related to hydraulic fracturing operation in the field.

  9. Numerical modeling of fracking fluid migration through fault zones and fractures in the North German Basin

    Science.gov (United States)

    Pfunt, Helena; Houben, Georg; Himmelsbach, Thomas

    2016-09-01

    Gas production from shale formations by hydraulic fracturing has raised concerns about the effects on the quality of fresh groundwater. The migration of injected fracking fluids towards the surface was investigated in the North German Basin, based on the known standard lithology. This included cases with natural preferential pathways such as permeable fault zones and fracture networks. Conservative assumptions were applied in the simulation of flow and mass transport triggered by a high pressure boundary of up to 50 MPa excess pressure. The results show no significant fluid migration for a case with undisturbed cap rocks and a maximum of 41 m vertical transport within a permeable fault zone during the pressurization. Open fractures, if present, strongly control the flow field and migration; here vertical transport of fracking fluids reaches up to 200 m during hydraulic fracturing simulation. Long-term transport of the injected water was simulated for 300 years. The fracking fluid rises vertically within the fault zone up to 485 m due to buoyancy. Progressively, it is transported horizontally into sandstone layers, following the natural groundwater flow direction. In the long-term, the injected fluids are diluted to minor concentrations. Despite the presence of permeable pathways, the injected fracking fluids in the reported model did not reach near-surface aquifers, either during the hydraulic fracturing or in the long term. Therefore, the probability of impacts on shallow groundwater by the rise of fracking fluids from a deep shale-gas formation through the geological underground to the surface is small.

  10. Deciphering the depositional environment of the laminated Crato fossil beds (Early Cretaceous, Araripe Basin, North-eastern Brazil)

    DEFF Research Database (Denmark)

    Heimhofer, Ulrich; Ariztegui, Daniel; Lenniger, Marc

    2010-01-01

    The laminated limestones of the Early Cretaceous Crato Formation of the Araripe Basin (North-eastern Brazil) are world-famous for their exceptionally well-preserved and taxonomically diverse fossil fauna and flora. Whereas the fossil biota has received considerable attention, only a few studies...... bedded, pale to dark lamination. To obtain information on palaeoenvironmental conditions, sample slabs derived from three local stratigraphic sections within the Araripe Basin were studied using high-resolution multiproxy techniques including detailed logging, petrography, mu-XRF scanning and stable......-poor meteoric water source and support a continental freshwater setting for the Nova Olinda Member. The delta C-13 values, which are comparatively rich in C-13 (between -0.1 and +1.9 parts per thousand), are interpreted to reflect reduced throughflow of water in a restricted basin, promoting...

  11. Two-dimensional basement modeling of central loop transient electromagnetic data from the central Azraq basin area, Jordan

    Science.gov (United States)

    Yogeshwar, P.; Tezkan, B.

    2017-01-01

    Thick sedimentary sequences are deposited in the central area of the Azraq basin in Jordan consisting mostly of hyper-saline clay and various evaporates. These sediment successions form the 10 km × 10 km large Azraq mudflat and are promising archives for a palaeoclimatical reconstruction. Besides palaeoclimatical research, the Azraq area is of tremendous importance to Jordan due to groundwater and mineral resources. The heavy exploitation of groundwater has lead to a drastic decline of the water table and drying out of the former Azraq Oasis. Two 7 and 5 km long transects were investigated from the periphery of the mudflat across its center using a total of 150 central loop transient electromagnetic (TEM) soundings. The scope of the survey was to detect the thickness of sedimentary deposits along both transects and to provide a basis for future drilling activities. We derive a two-dimensional model which can explain the TEM data for all soundings along each profile simultaneously. Previously uncertain depths of geological boundaries were determined along both transects. Particularly the thickness of the deposited mudflat sediments was identified and ranges from 40 m towards the periphery down to approximately 130 m at the deepest location. Besides that, the depth and lateral extent of a buried basalt layer was identified. In the basin center the groundwater is hyper-saline. The lateral extent of the saline water body was determined precisely along both transects. In order to investigate the detectability of the basement below the high conductive mudflat sediments an elaborate two-dimensional modeling study was performed. Both, the resistivity and depth of the basement were varied systematically. The basement resistivity cannot be determined precisely in most zones and may range roughly between 1 and 100 Ωm without deteriorating the misfit. In contrast to that, the depth down to the basement is detected accurately in most zones and along both transects. Varying

  12. Uplifting of the Jiamusi Block in the eastern Central Asian Orogenic Belt, NE China: evidence from basin provenance and geochronology

    Science.gov (United States)

    Liu, Yongjiang; Wen, Quanbo; Han, Guoqing; Li, Wei

    2010-05-01

    The main part of Jiamusi Block, named as Huanan-Uplift, is located in the northeastern Heilongjiang, China. The Huanan-Uplift is surrounded by many relatively small Mesozoic-Cenozoic basins, e.g. Sanjiang Basin, Hulin Basin, Boli Basin, Jixi Basin, Shuangyashan Basin and Shuanghua Basin. However previous research works were mainly focused on stratigraphy and palaeontology of the basins, therefore, the coupling relation between the uplift and the surrounding basins have not been clear. Based on the field investigations, conglomerate provenance studies of the Houshigou Formation in Boli Basin, geochronology of the Huanan-Uplift basement, we have been studied the relationships between Huanan-Uplift and the surrounding basins. The regional stratigraphic correlations indicates that the isolated basins in the area experienced the same evolution during the period of the Chengzihe and the Muling Formations (the Early Cretaceous). The paleogeography reconstructions suggest that the area had been a large-scale basin as a whole during the Early Cretaceous. The Huanan-Uplift did not exist. The paleocurrent directions, sandstone and conglomerate provenance analyses show that the Huanan-Uplift started to be the source area of the surrounding basins during the period of Houshigou Formation (early Late Cretaceous), therefore, it suggests that the Jiamusi Block commenced uplift in the early Late Cretaceous. The granitic gneisses in Huanan-Uplift give 494-415 Ma monazite U-Th-total Pb ages, 262-259 Ma biotite and 246-241 Ma K-feldspar 40Ar/39Ar ages. The cooling rates of 1-2 ℃/Ma from 500-260 Ma and 10-11 ℃/Ma from 260-240 Ma have been calculated based on the ages. This suggests that the Jiamusi Block had a rapid exhumation during late Permian, which should be related to the closure of the Paleo-Asian Ocean between the Siberian and North China continents. It is concluded that during the late Paleozoic the Jiamusi Block was stable with a very slow uplifting. With the closure of

  13. Phylogeographic Analysis of Blastomyces dermatitidis and Blastomyces gilchristii Reveals an Association with North American Freshwater Drainage Basins.

    Directory of Open Access Journals (Sweden)

    Lisa R McTaggart

    Full Text Available Blastomyces dermatitidis and Blastomyces gilchristii are dimorphic fungal pathogens that cause serious pulmonary and systemic infections in humans. Although their natural habitat is in the environment, little is known about their specific ecologic niche(s. Here, we analyzed 25 microsatellite loci from 169 strains collected from various regions throughout their known endemic range in North America, representing the largest and most geographically diverse collection of isolates studied to date. Genetic analysis of multilocus microsatellite data divided the strains into four populations of B. dermatitidis and four populations of B. gilchristii. B. dermatitidis isolates were recovered from areas throughout North America, while the B. gilchristii strains were restricted to Canada and some northern US states. Furthermore, the populations of both species were associated with major freshwater drainage basins. The four B. dermatitidis populations were partitioned among (1 the Nelson River drainage basin, (2 the St. Lawrence River and northeast Atlantic Ocean Seaboard drainage basins, (3 the Mississippi River System drainage basin, and (4 the Gulf of Mexico Seaboard and southeast Atlantic Ocean Seaboard drainage basins. A similar partitioning of the B. gilchristii populations was observed among the more northerly drainage basins only. These associations suggest that the ecologic niche where the sexual reproduction, growth, and dispersal of B. dermatitidis and B. gilchristii occur is intimately linked to freshwater systems. For most populations, sexual reproduction was rare enough to produce significant linkage disequilibrium among loci but frequent enough that mating-type idiomorphic ratios were not skewed from 1:1. Furthermore, the evolutionary divergence of B. dermatitidis and B. gilchristii was estimated at 1.9 MYA during the Pleistocene epoch. We suggest that repeated glaciations during the Pleistocene period and resulting biotic refugia may have

  14. Circulation characteristics of persistent cold spells in central-eastern North America

    Science.gov (United States)

    Li, Zhenhua; Manson, Alan H.; Li, Yanping; Meek, Chris

    2017-02-01

    The circulation patterns of persistent cold weather spells with durations longer than 10 days in central-eastern North America (United States and Canada; 32°-52°N, 95°-65°W) are investigated by using NCEP reanalysis data from 1948 to 2014. The criteria for the persistent cold spells are: (1) three-day averaged temperature anomalies for the regional average over the central-eastern United States and Canada must be below the 10th percentile, and (2) such extreme cold spells must last at least 10 days. The circulation patterns associated with these cold spells are examined to find the common signals of these events. The circulation anomaly patterns of these cold spells are categorized based on the El Niño-Southern Oscillation, Arctic Oscillation (AO), and other climate indices. The atmospheric circulation patterns that favor the cold spells are identified through composites of geopotential height maps for the cold spells. Negative AO phases favor persistent cold spells. Phases of sea surface temperature (SST) modes that are associated with warm SSTs in the eastern extratropical Pacific also favor persistent cold events in the study region. Stratospheric polar vortex breakdown alone is not a good predictor for the regional extreme cold spells in central-eastern North America. The meridional dispersions of quasi-stationary Rossby waves in the Pacific-North America sector in terms of cut-off zonal wavenumber modulated by background flow are analyzed to provide insight into the difference in evolution of the cold spells under different mean AO phases. The waveguide for AO > 1 is in a narrow latitudinal band centered on 40°N, whereas the waveguide for AO <-1 is in a broader latitudinal band from 40° to 65°N. The circulation patterns and lower boundary conditions favorable for persistent cold spells identified by this study can be a stepping-stone for improving winter subseasonal forecasting in North America.

  15. Structural control of the basement in the central portion of the Santos Basin-Brazil; Controle estrutural do embasamento na porcao central da Bacia de Santos

    Energy Technology Data Exchange (ETDEWEB)

    Izeli, Maira G.B.; Morales, Norberto; Souza, Iata A. de [Universidade Estadual Paulista (UNESP), Rio Claro, SP (Brazil). Inst. de Geociencias e Ciencias Exatas

    2008-07-01

    New discoveries of oil in deep water and ultra-deep water in Santos Basin suggest that it needs to be studied to better understanding of basement structures and their role in the basin control and configuration. This study characterizes the main tectonic structures of a portion at the central area of this basin, looking for their relation to the geological basement framework. The study is based on the integration of the geological and geophysical data from subsurface (offshore) and surface of the adjacent continent. These analyses include the continental structures that continue in direction of this basin (Guapiara Lineament and Ponta Grossa Arc), checking their possible influence on the basin evolution and deformation. To achieve the proposed goals, the Precambrian basement lineaments were extracted from the offshore area using remote sensing, as result was obtained strong NW-SE structural trend. According to the interpretation of seismic sections, it is possible to observe that this portion of the basin presents main NE-SW structural trend, and most of the structures are typical of passive margin and halokintics process. It is possible to see that some recognized faults in the rift deposits may be coinciding with the main continental guidelines which are projected into the basin. (author)

  16. From Flysch to Molasse-Sedimentary and Tectonic Evolution of Late Caledonian-Early Hercynian Foreland Basin in North Qilian Mountains

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The Late Caledonian to Early Hercynian North Qilian orogenic belt in northwestern China is an elongate tectonic unit situated between the North China plate in the north and the Qaidam plate in the south. North Qilian started in the latest Proterozoic to Cambrian as a rift basin on the southern margin of North China, and evolved later to an archipelagic ocean and active continental margin during the Ordovician and a foreland basin from Silurian to the Early and Middle Devonian. The Early Silurian flysch and submarine alluvial fan, the Middle to Late Silurian shallow marine to tidal flat deposits and the Early and Middle Devonian terrestrial molasse are developed along the corridor Nanshan. The shallowing-upward succession from subabyssal flysch, shallow marine, tidal flat to terrestrial molasse and its gradually narrowed regional distribution demonstrate that the foreland basin experienced the transition from flysch stage to molasse stage during the Silurian and Devonian time.

  17. 78 FR 33891 - North Central Railway Association, Inc.-Abandonment Exemption-in Franklin and Hardin Counties, Iowa

    Science.gov (United States)

    2013-06-05

    ... (Sub-No. 3X)] North Central Railway Association, Inc.--Abandonment Exemption-- in Franklin and Hardin... milepost 201.46 at or near Ackley, and milepost 191.0 at or near Geneva, in Franklin and Hardin...

  18. Accumulation rates from central North Greenland during the past 700 year

    Science.gov (United States)

    Karlsson, Nanna B.; Eisen, Olaf; Nielsen, Lisbeth T.; Kipfstuhl, Sepp; Freitag, Johannes; Paden, John D.; Dahl-Jensen, Dorthe; Winter, Anna; Wilhelms, Frank

    2016-04-01

    A key variable when interpreting the evolution and mass loss from polar ice sheets is the input from the surface mass balance. While ice core records contain information on past accumulation rates, they always only provide information for a single location. Here, we present spatially distributed accumulation rates from central northern Greenland, specifically the area between the NEEM (North Greenland Eemian Drilling) and NGRIP (North Greenland Ice Core Project) ice core drill sites. The accumulation rates have been reconstructed using ice-penetrating radar, firn core measurements and inverse methods, and we are able to retrieve both spatial and temporal changes in the accumulation over an area spanning 300 km by 300 km. We investigate the stability of the accumulation pattern over the past several hundred years, and we address the question of how well the measured accumulation rates at the ice core sites capture the regional variations in accumulation. We find that while the accumulation rates at NEEM have been stable for the past 700 years, the NGRIP site has experienced fluctuations in accumulation rate. We interpret this as an indication of shifts in the dominating weather pattern over the ice divide in central North Greenland.

  19. New sedimentological and palynological data from surface Miocene strata in the central Amazonas Basin area

    Directory of Open Access Journals (Sweden)

    Emílio Alberto Amaral Soares

    Full Text Available ABSTRACT The scarcity of stratigraphic data has hindered the demarcation of the outcropping area of Miocene deposits of the Amazon Basin, represented informally by the Novo Remanso Formation. Moreover, this unit is characterized by a sparse and irregular geographic distribution due to its sedimentological features and rare fossil content. Miocene deposits cropping out in central Amazonas Basin area were described in sedimentological terms and analyzed palynologically. All analyses were undertaken in samples collected at the Uatumã River banks (Itapiranga and São Sebastião do Uatumã cities. Lithostratigraphic data shows that Novo Remanso Formation consists of sandstones, with subordinate conglomerates and pelites, characteristic of a meandering fluvial paleosystem, with fluvial channel, point bar, floodplain and crevasse splay facies. The palynoflora retrieved from five samples consists exclusively of continental-origin palynomorphs dominated by angiosperms species. Trilete spores are well represented, while gymnosperms pollen grains are minor components. The presence of Psilastephanoporites tesseroporus, Syncolporites poricostatus, Jandufouria seamrogiformis and Polypodiaceoisporites potoniei ensure these deposits fits into the Grimsdalea magnaclavata palynozone (Regali et al. 1974a, b, and the Grimsdalea magnaclavata/Crassoretitriletes vanraadshooveni palynozones of Jaramillo et al. (2011 considered Middle Miocene age. This age is confirmed by the zonation of Jaramillo et al. (2011, based on the LADs of Bombacacidites baumfalki (11.57Ma and Crototricolpites annemariae (12.91Ma; and the FAD of Psilastephanoporites tesseroporus (14.00Ma. With these new data presented herein, it is possible to assume that the Miocene strata represented by the Novo Remanso Formation covers a larger area in the basin than previously considered, and that it may be extended for about 300 km until the Manacapuru village, indicating a Miocene subsidence phase.

  20. Water resources in the Big Lost River Basin, south-central Idaho

    Science.gov (United States)

    Crosthwaite, E.G.; Thomas, C.A.; Dyer, K.L.

    1970-01-01

    The Big Lost River basin occupies about 1,400 square miles in south-central Idaho and drains to the Snake River Plain. The economy in the area is based on irrigation agriculture and stockraising. The basin is underlain by a diverse-assemblage of rocks which range, in age from Precambrian to Holocene. The assemblage is divided into five groups on the basis of their hydrologic characteristics. Carbonate rocks, noncarbonate rocks, cemented alluvial deposits, unconsolidated alluvial deposits, and basalt. The principal aquifer is unconsolidated alluvial fill that is several thousand feet thick in the main valley. The carbonate rocks are the major bedrock aquifer. They absorb a significant amount of precipitation and, in places, are very permeable as evidenced by large springs discharging from or near exposures of carbonate rocks. Only the alluvium, carbonate rock and locally the basalt yield significant amounts of water. A total of about 67,000 acres is irrigated with water diverted from the Big Lost River. The annual flow of the river is highly variable and water-supply deficiencies are common. About 1 out of every 2 years is considered a drought year. In the period 1955-68, about 175 irrigation wells were drilled to provide a supplemental water supply to land irrigated from the canal system and to irrigate an additional 8,500 acres of new land. Average. annual precipitation ranged from 8 inches on the valley floor to about 50 inches at some higher elevations during the base period 1944-68. The estimated water yield of the Big Lost River basin averaged 650 cfs (cubic feet per second) for the base period. Of this amount, 150 cfs was transpired by crops, 75 cfs left the basin as streamflow, and 425 cfs left as ground-water flow. A map of precipitation and estimated values of evapotranspiration were used to construct a water-yield map. A distinctive feature of the Big Lost River basin, is the large interchange of water from surface streams into the ground and from the

  1. Quaternary Geology and Geomorphology of Terna River Basin in West Central India

    Directory of Open Access Journals (Sweden)

    Mohammad Babar

    2012-12-01

    Full Text Available This paper presents the morphostratigraphy, lithostratigraphy and sedimentary structures of Terna River basin in the Deccan Basaltic Province (DBP of West Central India. These Quaternary deposits have been divided into three informal formations (i dark grey silt formation – Late Holocene, (ii Light grey silt formations – Early Holocene, (iii Dark grayish brown silt formation – Late Pleistocene with the older Quaternary Alluvial deposits of Upper Pleistocene age. The fine clay and silt formations in the lower reaches reflect that the streams are of low gradient and more sinuous. The river shows evidences of channel movement by avulsion, largely controlled by lineaments. Palaeo-levees, in the form 4–5 m high ridges exist along the Terna River floodplain, specifically in the Ter, Killari, Sastur, Dhuta and Makni villages. Several lineaments occur along NE-SW, NW-SE, E-W and WNW-ESE directions, which control the basement structure in the study area. The values of the Topographic Sinuosity Index (TSI indicate rejuvenation of the area leading to the dominance of topography on the sinuosity of the river channels. The break in slope in the long profile is also indication of the Quaternary tectonic uplift of the area. Radiocarbon dating of some charcoal fragments collected from folded beddings indicates that paleoseismic activity might have taken place along the basin between AD 120 and AD 1671.

  2. Upper Jurassic basin axial turbidites within the Gertrud Graben, Danish Central Graben

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, E.S.; Jepsen, A.M.; Maver, K.G.

    1998-10-01

    Fore more than twenty years, the Jurassic succession in the Danish Central Graben has been subject to intense exploration for hydrocarbons. Approximately 43 wildcats have been drilled and most of these tested were structural traps located on footwall crests. The reservoirs encountered were Middle and Upper Jurassic sandstones deposited mainly in near shore depositional environments. Some of these wells penetrated thin turbidites of Late Jurassic to Early Cretaceous age. Within the Gertrud Graben distinct seismic anomalies indicate the presence of basin floor turbidites, which can be correlated to fan fringe turbites encountered in the Jeppe-1, Gwen-2 and Mona-1 wells. Within the Gertrud Graben, seismic anomalies characterized by high amplitude reflections with in an otherwise transparent reflection pattern have been recognized. The zone with high amplitude reflections correlates with thin turbidites with oil shows encountered in the Jeppe-1 well. The turbiditic sandstone succession has a gross thickness of 25 m and a net to gross of 75%, with porosity up to 10%. The presence of oil shows in the thin turbiditic sandstones in the Jeppe-1 well, drilled on a footwall crest, suggests the possibility of thicker sandstones in the basinal areas. The aim of this study is to map the distribution of the seismic anomalies by performing seismic inversion. Seismic inversion is used to derive acoustic impedance as a lithology indicator and to establish a geological model that is a likely prediction of the lithology and architecture of the depositional system. (EG) 2 fig., 17 refs.

  3. Correlation of the oldest Toba Tuff to sediments in the central Indian Ocean Basin

    Indian Academy of Sciences (India)

    J N Pattan; M Shyam Prasad; E V S S K Babu

    2010-08-01

    We have identified an ash layer in association with Australasian microtektites of ∼0.77Ma old in two sediment cores which are ∼450 km apart in the central Indian Ocean Basin (CIOB). Morphology and chemical composition of glass shards and associated microtektites have been used to trace their provenance. In ODP site 758 from Ninetyeast Ridge, ash layer-D (13 cm thick, 0.73–0.75 Ma) and layer-E (5 cm thick, 0.77–0.78 Ma) were previously correlated to the oldest Toba Tuff (OTT) eruptions of the Toba caldera, Sumatra. In this investigation, we found tephra ∼3100 km to the southwest of Toba caldera that is chemically identical to layer D of ODP site 758 and ash in the South China Sea correlated to the OTT. Layer E is not present in the CIOB or other ocean basins. The occurrence of tephra correlating to layer D suggests a widespread distribution of OTT tephra (∼3.6 × 107 km2), an ash volume of at least ∼1800 km3, a total OTT volume of 2300 km3, and classification of the OTT eruption as a super-eruption.

  4. Deep Structure and Evolution of The Central Graben, North Sea: Constraints From Seismic Observations and Numerical Dynamic Modelling.

    Science.gov (United States)

    Balling, N.; Frederiksen, S.; Nielsen, L.; Nørmark, E.; Nielsen, S. B.; Jacobsen, B. H.

    The Central Graben forms the southern arm of a three-arm rift system in the North Sea, with the Viking Graben as the northern arm and the Moray Firth Basin as the western arm. It is a 70-130 km wide graben with a length of about 550 km. High qual- ity normal-incidence and wide-angle seismic data from the MONA LISA deep seismic experiment across the Central Graben show crustal thinning by a factor of 2 in areas of thickest sedimentary sequences and localized seismic reflectivity in the upper mantle dipping away from the deepest parts of the graben. A numerical dynamic lithospheric model with significant Triassic and Late Jurassic extensional phases as well as Mid- dle Jurassic thermal doming accounts for the observed up to 8 km of Late Permian to Cenozoic sediments in the deepest parts of the Graben, for most of the observed lateral thickness variation of sedimentary formations and is consistent with both the deep-seismic data, present-day heat-flow and gravity data. The detailed crustal model produced by joint inverse modelling of seimic refraction data and gravity data shows a distinct thinning of the crust and local elevation of Moho by up to 5 km in a 40 km narrow zone below areas of thick upper Jurassic sediments. This Moho structure suggests that a relatively shallow and otherwise strong uppermost mantle has been interrupted, perhaps by mantle shear zones induced by strain softening as in our nu- merical model. The integrated seismic observational and numerical modelling results indicate that an initially pure-shear donimated extensional regime changed into an ex- tensional regime where simple shear played an important part with mantle shear zones developed during the Late Jurassic extension.

  5. Postwildfire preliminary debris flow hazard assessment for the area burned by the 2011 Las Conchas Fire in north-central New Mexico

    Science.gov (United States)

    Tillery, Anne C.; Darr, Michael J.; Cannon, Susan H.; Michael, John A.

    2011-01-01

    The Las Conchas Fire during the summer of 2011 was the largest in recorded history for the state of New Mexico, burning 634 square kilometers in the Jemez Mountains of north-central New Mexico. The burned landscape is now at risk of damage from postwildfire erosion, such as that caused by debris flows and flash floods. This report presents a preliminary hazard assessment of the debris-flow potential from 321 basins burned by the Las Conchas Fire. A pair of empirical hazard-assessment models developed using data from recently burned basins throughout the intermountain western United States was used to estimate the probability of debris-flow occurrence and volume of debris flows at the outlets of selected drainage basins within the burned area. The models incorporate measures of burn severity, topography, soils, and storm rainfall to estimate the probability and volume of debris flows following the fire. In response to a design storm of 28.0 millimeters of rain in 30 minutes (10-year recurrence interval), the probabilities of debris flows estimated for basins burned by the Las Conchas Fire were greater than 80 percent for two-thirds (67 percent) of the modeled basins. Basins with a high (greater than 80 percent) probability of debris-flow occurrence were concentrated in tributaries to Santa Clara and Rio del Oso Canyons in the northeastern part of the burned area; some steep areas in the Valles Caldera National Preserve, Los Alamos, and Guaje Canyons in the east-central part of the burned area; tributaries to Peralta, Colle, Bland, and Cochiti canyons in the southwestern part of the burned area; and tributaries to Frijoles, Alamo, and Capulin Canyons in the southeastern part of the burned area (within Bandelier National Monument). Estimated debris-flow volumes ranged from 400 cubic meters to greater than 72,000 cubic meters. The largest volumes (greater than 40,000 cubic meters) were estimated for basins in Santa Clara, Los Alamos, and Water Canyons, and for two

  6. Composition and Genesis of Zeolitic Claystones from the Central Indian Ocean Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We examined more than fifty indurated sediments recovered from the Central Indian Ocean Basin (CIOB) during the course of collection for manganese nodules and crusts. The samples occur as slabs either over which ferromanganese oxides are present or over a substrate of altered oceanic basalt in conjunction with palagonite or within the nucleus of manganese nodules.Mineralogically and compositionally, the samples show a mixture of phillipsite, palagonite and montmorillonite. We suggest that the volcanogenic precursors occurring in the CIOB were subjected to varying degrees of alteration under the influence of low temperature conditions, resulting in the formation of zeolitic claystones. The CIOB samples have similarities to those reported from various sites in the world oceans.

  7. Physical characteristics of stream subbasins in the Pomme de Terre River Basin, west-central Minnesota

    Science.gov (United States)

    Lorenz, D.L.; Payne, G.A.

    1994-01-01

    Data describing the physical characteristics of stream subbasins upstream from selected points on streams in the Pomme de Terre River Basin, located in west-central Minnesota, are presented in this report. The physical characteristics are the drainage area of the subbasin, the percentage area of the subbasin covered only by lakes, the percentage area of the subbasin covered by both lakes and wetlands, the main-channel length, and the main-channel slope. The points on the stream include outlets of subbasins of at least 5 square miles, outfalls of sewage treatment plants, and locations of U.S. Geological Survey low-flow, high-flow, and continuous-record gaging stations.

  8. Jinning granodiorite and diorite deeply concealed in the central Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    LI; Yuejun; SONG; Wenjie; WU; Genyao; WANG; Yifen; LI; Yupi

    2005-01-01

    The 7200-m-deep Well Tacan 1 in the central Tarim Basin is the deepest in China. Purplish gray medium-grained granodiorite containing dark gray fine-grained diorite xenolith is revealed at the base of the well (7169―7200 m), and they are results of the Jinning magmatic activities. Trace-element geochemistry and REE profiles of both rock types are similar, indicating that they are calc-alkaline series I-type granitoid. Proxies of diorite signify the development of a magmatic arc due to subduction at ca. 1200 Ma. The granodiorite was formed before 890―932 Ma. However, more study is needed to clarify if the arc diorite represents a ca. 300 Ma extension of the subduction or a reactivation during the orogenic collision event at ca. 900 Ma.

  9. Group classification of mixed oils in central Junggar Basin, Northwest China and their migration

    Institute of Scientific and Technical Information of China (English)

    WANG Xulong; SHI Xinpu; CAO Jian; LAN Wenfang; TAO Guoliang; HU Wenxuan; YAO Suping

    2010-01-01

    The produced oils in central Junggar Basin are commonly mixed in origin. In this paper, in order to reveal this complexity and thereby provide valuable clues to the study of oil source and formation mechanism, genetic groups of the mixed oils were classified and their migration/accumulation was investigated. Based on the artificial oil mixing experiments, some representative biomarkers of the mixed oils showed varying tendencies according to mixing ratios of the oils. Hence, these biomarkers are useful for determining the origin of the mixed oils. According to the criteria, oils in the area were divided into four basic groups, i.e., the Lower Permian Fengcheng oil, the Middle Permian Lower Wuerhe oil, the Jurassic source derived oil, and the mixed oil (including the Lower and Middle Permian mixed oil and the Permian and Jurassic mixed oil). Oil migration and accumulation were discussed in combination with the geological background.

  10. Extensional Basins in a Convergent Margin: Oligocene-Early Miocene Salar de Atacama and Calama basins, Central Andes

    Science.gov (United States)

    Jordan, T. E.; Mpodozis, C.; Blanco, N.; Pananont, P.; Dávila, F.

    2004-12-01

    The Salar de Atacama Basin (SdAB) is the largest and most persistent sedimentary basin of northern Chile, accumulating nonmarine sediment from Cretaceous to modern times. Its northwestern neighbor, the Calama, was a Cenozoic basin. Although SdAB was in the backarc zone early in the Andean orogeny, both are now forearc basins. Others demonstrated that the basins overlie anomalously cold, strong, and dense crust and lithosphere. We focus on an extensional Oligocene basin stage. Interpretation of the basin-controlling faults is based on seismic reflection studies supported by field relations. The SdAB is limited to the west by the NNE-trending, steeply east-dipping, Paciencia Fault (PF). The PF experienced 5-7 km of down-to-the-east offset during the Oligocene-early Miocene. Syntectonic strata, an arid succession of siliciclastics and evaporites, are asymmetric, with thicknesses of 5000 m and abundant halite adjacent to the PF, and of 1000 m with fine detrital clastic strata 25 km farther east. Relations in conglomeratic growth strata that overlap the PF also demonstrate normal displacement during sediment accumulation. Seismic data reveal that a buried normal fault with 1-1.5 km down-to-the-east displacement limits the western margin of the Oligocene-Miocene Calama siliciclastic basin fill. Regionally, Oligocene-early Miocene margin-parallel strike-slip deformation dominated northwest of the basins, contributing sinistral offset (West Fissure Fault) to the northern segment of the long-lived Domeyko Fault System. The new SdAB and Calama data reveal that a 20,000 km2 domain of extensional basins existed within the dominantly strike-slip region. Even if PF and the fault in the Calama Basin were transtensional, the proportion of extension to strike-slip displacement is much greater in these basins than elsewhere in northern Chile. Further study is required to understand what combination of factors caused this kinematic distinction as well as delayed the onset of CVZ

  11. Wet and dry nitrogen deposition in the central Sichuan Basin of China

    Science.gov (United States)

    Kuang, Fuhong; Liu, Xuejun; Zhu, Bo; Shen, Jianlin; Pan, Yuepeng; Su, Minmin; Goulding, Keith

    2016-10-01

    Reactive nitrogen (Nr) plays a key role in the atmospheric environment and its deposition has induced large negative impacts on ecosystem health and services. Five-year continuous in-situ monitoring of N deposition, including wet (total nitrogen (WTN), total dissolved nitrogen (WTDN), dissolved organic nitrogen (WDON), ammonium nitrogen (WAN) and nitrate nitrogen (WNN)) and dry (DNH3, DHNO3, DpNH4+, DpNO3- and DNO2) deposition, had been conducted since August 2008 to December 2013 (wet) and May 2011 to December 2013 (dry) in Yan-ting, China, a typical agricultural area in the central Sichuan Basin. Mean annual total N deposition from 2011 to 2013 was 30.8 kg N ha-1 yr-1, and speculated that of 2009 and 2010 was averaged 28.2 kg N ha-1 yr-1, respectively. Wet and dry N deposition accounted for 76.3% and 23.7% of annual N deposition, respectively. Reduced N (WAN, DNH3 and DpNH4+) was 1.7 times of oxidized N (WNN, DHNO3, DNO2 and DpNO3-) which accounted for 50.9% and 30.3% of TN, respectively. Maximum loadings of all N forms of wet deposition, gaseous NH3, HNO3 and particulate NH4+ in dry deposition occurred in summer and minimum loadings in winter. Whether monthly, seasonal or annual averaged, dissolved N accounted for more than 70% of the total. N deposition in the central Sichuan Basin increased during the sampling period, especially that of ammonium compounds, and has become a serious threat to local aquatic ecosystems, the surrounding forest and other natural or semi-natural ecosystems in the upper reaches of the Yangtze River.

  12. Permian and Triassic microfloral assemblages from the Blue Nile Basin, central Ethiopia

    Science.gov (United States)

    Dawit, Enkurie L.

    2014-11-01

    Palynological investigation was carried out on surface samples from up to 400 m thick continental siliciclastic sediments, here referred to as “Fincha Sandstone”, in the Blue Nile Basin, central Ethiopia. One hundred sixty species were identified from 15 productive samples collected along a continuous road-cut exposure. Six informal palynological assemblage zones have been identified. These assemblage zones, in ascending order, are: “Central Ethiopian Permian Assemblage Zone - CEPAZ I”, earliest Permian (Asselian-Sakmarian); “CEPAZ II”, late Early Permian (Artinskian-Kungurian); CEPAZ III - Late Permian (Kazanian-Tatarian); “CETAZ IV”, Lower Triassic (Olenekian Induan); “CETAZ V”, Middle Triassic (Anisian Ladinian); “CETAZ VI”, Late Triassic (Carnian Norian). Tentative age ranges proposed herein are compared with faunally calibrated palynological zones in Gondwana. The overall composition and vertical distribution of miospores throughout the studied section reveals a wide variation both qualitatively and quantitatively. The high frequency of monosaccate pollen in CEPAZ I may reflect a Glossopterid-dominated upland flora in the earliest Permian. The succeeding zone is dominated by straite/taeniate disaccate pollen and polyplicates, suggesting a notable increase in diversity of glossopterids. The decline in the diversity of taeniate disaccate pollen and the concomitant rise in abundance of non-taeniate disaccates in CEPAZ III may suggest the decline in Glossopteris diversity, though no additional evidence is available to equate this change with End-Permian extinction. More diverse and dominant non-taeniate, disaccate, seed fern pollen assignable to FalcisporitesAlisporites in CETAZ IV may represent an earliest Triassic recovery flora. The introduction of new disaccate forms with thick, rigid sacci, such as Staurosaccites and Cuneatisporites, in CETAZ V and VI may indicate the emergence of new gymnospermous plants that might have favourably

  13. Characterisation of the bacterial populations in a saline heat storage aquifer in the North German Basin

    Science.gov (United States)

    Alawi, M.; Lerm, S.; Vetter, A.; Vieth, A.; Mangelsdorf, K.; Seibt, A.; Wolfgramm, M.; Würdemann, H.

    2009-04-01

    The colonization and the ecology of microorganisms in the deep biosphere arouse increasing interest of scientists because of utilizing the subsurface for e.g. energy storage and recovery. The research project AquiScreen investigates the operational reliability of eight geothermally used groundwater systems in Germany under microbial, geochemical, mineralogical, and petrological aspects. This study shows the results of the heat storage in Neubrandenburg (depth: 1250 m), a typical site for saline fluids in the North German Basin. The seasonal alternation in charge and discharge mode enabled sampling the warm (75˚ C) and the cold (45˚ C) side of the geothermal doublet. The analyses focus on microbially induced corrosion on plant components and scaling resulting in filter and/or formation clogging. Microbiological analyses were carried out with fluid and solid phase samples by 16S rDNA based Single Strand Conformation Polymorphism (SSCP) fingerprinting. The analyses are utilized to evaluate the impact of microbial populations on such systems. The genetic fingerprinting revealed significant differences in the bacterial community structure between the warm and cold side of the heat storage. Since the geochemical analyses revealed no remarkable differences, the temperature might be crucial for the different community structures. At the warm side of the aquifer the identified bacteria are closely related to Variovorax and Sphingomonas. At the cold side of the heat storage sulphate reducing and fermentative bacteria were detected. These results correspond with locally observed iron sulphide precipitation and corrosion processes on plant components. Particularly the bacterial population of the cold side was studied over a period of two years. Thereby seasonal changes in the abundance of the identified bacteria, depending on the operational mode of the geothermal plant, were observed. After a malfunction in the pump system of the cold side of the heat storage changes in

  14. The implications of geology, soils, and vegetation on landscape morphology: Inferences from semi-arid basins with complex vegetation patterns in Central New Mexico, USA

    Science.gov (United States)

    Yetemen, Omer; Istanbulluoglu, Erkan; Vivoni, Enrique R.

    2010-04-01

    This paper examines the relationship between land surface properties (e.g. soil, vegetation, and lithology) and landscape morphology quantified by the catchment descriptors: the slope-area (S-A) relation, curvature-area (C-A) relation, and the cumulative area distribution (CAD), in two semi-arid basins in central New Mexico. The first site is composed of several basins located in today's desert elevations with mesic north-facing and xeric south-facing hillslopes underlain by different lithological formations. The second site is a mountainous basin exhibiting vegetation gradients from shrublands in the lower elevations to grasslands and forests at higher elevations. All three land surface properties were found to have significant influences on the S-A and C- A relations, while the power-law exponents of the CADs for these properties did not show any significant deviations from the narrow range of universal scaling exponents reported in the literature. Among the three different surface properties we investigated, vegetation had the most profound impact on the catchment descriptors. In the S-A diagrams of the aspect-controlled ecosystems, we found steeper slopes in north-facing aspects than south-facing aspects for a given drainage area. In elevation-controlled ecosystems, forested landscapes exhibited the steepest slopes for the range of drainage areas examined, followed by shrublands and grasslands in all soil textures and lithologies. In the C-A diagrams, steeper slopes led to a higher degree of divergence on hillslopes and a higher degree of convergence in the valleys than shallower slopes. The influence of functional types of vegetation detected on observed topography provided some initial understanding of the potential impacts of life on the organization of topography. This finding also emphasizes the critical role of climate in catchment development. We suggest that climatic fluctuations that are capable of replacing vegetation communities could lead to highly

  15. Evaluating regional differences in macroinvertebrate communities from forested depressional wetlands across eastern and central North America.

    Energy Technology Data Exchange (ETDEWEB)

    Batzer, Darold, P.; Dietz-Brantley, Susan E.; Taylor, Barbera E.; DeBiase, Adrienne E.

    2005-02-12

    Batzer, Darold, P., Susan E. Dietz-Brantley, Barbera E. Taylor, and Adrienne E. DeBiase. 2005. Evaluating regional differences in macroinvertebrate communities from forested depressional wetlands across eastern and central North America. J. N. Am. Benthol. Soc. 24(2):403-414. Abstract. Forested depressional wetlands are an important seasonal wetland type across eastern and central North America. Macroinvertebrates are crucial ecosystem components of most forested depressional wetlands, but community compositions can vary widely across the region. We evaluated variation in macroinvertebrate faunas across eastern and central North America using 5 published taxa lists from forested depressional wetlands in Michigan, Ontario, Wisconsin, Florida, and Georgia. We supplemented those data with quantitative community descriptions generated from 17 forested depressional wetlands in South Carolina and 74 of these wetlands in Minnesota. Cluster analysis of presence/absence data from these 7 locations indicated that distinct macroinvertebrate communities existed in northern and southern areas. Taxa characteristic of northern forested depressionalwetlands included Sphaeriidae, Lumbriculidae, Lymnaeidae, Physidae, Limnephilidae, Chirocephalidae, and Hirudinea (Glossophoniidae and/or Erpodbellidae) and taxa characteristic of southern sites included Asellidae, Crangonyctidae, Noteridae, and Cambaridae. Quantitative sampling in South Carolina and Minnesota indicated that regionally characteristic taxa included some of the most abundant organisms, with Sphaeriidae being the 2nd most abundant macroinvertebrate in Minnesota wetlands and Asellidae being the 2nd most abundant macroinvertebrate in South Carolina wetlands. Mollusks, in general, were restricted to forested depressional wetlands of northern latitudes, a pattern that may reflect a lack of Ca needed for shell formation in acidic southern sites. Differences in community composition probably translate into region

  16. Implementation of MAR within the Rio Grande Basin of Central New Mexico, USA

    Science.gov (United States)

    Marley, Robert; Blandford, T. Neil; Ewing, Amy; Webb, Larry; Yuhas, Katherine

    2014-05-01

    The U.S. Bureau of Reclamation has identified the Rio Grande basin within Central New Mexico as one of several regions where water supplies are over-allocated and future conflicts over the inadequate resource are highly likely. Local water providers have consistently identified managed aquifer recharge (MAR) as an important tool to provide conjunctive management of surface-water, groundwater, and reclaimed water sources in order to extend the useful life of existing water sources. However, MAR projects have been slow to take root partly due to rigorous demonstration requirements, groundwater quality protection concerns, and ongoing water right uncertainties. At first glance the several thousand meters of unconsolidated basin-fill sediments hosting the regional aquifer appear to provide an ideal environment for the subsurface storage of surplus water. However, the basin has a complex structural and depositional history that impacts the siting and overall effectiveness of MAR systems. Several recharge projects are now in various stages of implementation and are overcoming site specific challenges including source water and ambient groundwater compatibility, low-permeability sediments and compartmentalization of the aquifer by extensive faulting, well clogging, and overall water quality management. This presentation will highlight ongoing efforts of these water providers to develop full-scale recharge facilities. The performance of natural in-channel infiltration, engineered infiltration galleries, and direct injection systems designed to introduce from 500 to 5,000 mega-liters per annum to target intervals present from 150 to 600 meters below ground surface will be described. Source waters for recharge operations include inter-basin transferred surface water and highly treated reclaimed water sources requiring from minor to extensive treatment pre-recharge and post-recovery. Operational complexities have raised concerns related to long-term operation and maintenance

  17. Diazotroph diversity in the sea ice, melt ponds and surface waters of the Eurasian Basin of the Central Arctic Ocean

    OpenAIRE

    Fernández-Méndez, Mar; Turk-Kubo, Kendra A.; Rapp, Josephine Z.; Buttigieg, Pier Luigi; Krumpen, Thomas; Jonathan P Zehr; Boetius, Antje

    2016-01-01

    The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which ...

  18. A preliminary classification of wetland plant communities in north-central Minnesota

    Science.gov (United States)

    Cowardin, L.M.; Johnson, D.H.

    1973-01-01

    A classification of wetland plant communities was developed for a study area in north-central Minnesota in order to analyze data on waterfowl use of habitat that were gathered by radio telemetry. The classification employs features of several earlier classifications in addition to new classes for bogs and lakeshore communities. Brief descriptions are given for each community, and the important plant species are listed. Discriminant function analysis was used for 40 plant species. Seventy-five percent of the stands studied were classified correctly by this technique. Average probabilities of assignment to communities were calculated and helped to identify distinct and poorly defined communities as well as the relationship among communities.

  19. Deleterious Emission Abatement through Structured Energy Use Pattern: A North Central Nigeria Perspective

    OpenAIRE

    Ajayi-Banji Ademola; Omotosho Olayinka; Amori Anthony; Alao Damilola; Igbode Imoisime; Abimbola Olufemi

    2016-01-01

    Holistic view of household energy consumption based on greenhouse gas emissions in the North Central cities of Nigeria was examined in this study. Scenarios considered were based on income level of energy users (low and high) and energy metering system (i.e. pre-paid and post-paid energy billing systems). Strong direct nexus was observed between energy use and emissions pattern. Energy utilization by post-paid category had higher weekly average value of 35.09 and 41.70 kWh as against 23.18 an...

  20. Hydrology and geochemistry of thermal ground water in southwestern Idaho and north-central Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Young, H.W.; Lewis, R.E.

    1980-12-01

    The study area occupies about 14,500 square miles in southwestern Idaho and north-central Nevada. Thermal ground water occurs under artesian conditions, in discontinuous or compartmented zones, in igneous or sedimentary rocks of Tertiary age. Ground-water movement is generally northward. Temperatures of the ground water range from about 30/sup 0/ to more than 80/sup 0/C. Chemical analyses of water from 12 wells and 9 springs indicate that nonthermal waters are a calcium bicarbonate type; thermal waters are a sodium bicarbonate type. Chemical geothermometers indicate probable maximum reservoir temperatures are near 100/sup 0/C. Concentration of tritium in the thermal water water is near zero.

  1. Transport and Retention of Nitrogen, Phosphorus and Carbon in North America’s Largest River Swamp Basin, the Atchafalaya River Basin

    Directory of Open Access Journals (Sweden)

    Y. Jun Xu

    2013-04-01

    Full Text Available Floodplains and river corridor wetlands may be effectively managed for reducing nutrients and carbon. However, our understanding is limited to the reduction potential of these natural riverine systems. This study utilized the long-term (1978–2004 river discharge and water quality records from an upriver and a downriver location of the Atchafalaya River to quantify the inflow, outflow, and inflow–outflow mass balance of total Kjeldahl nitrogen (TKN = organic nitrogen + ammonia nitrogen, nitrate + nitrite nitrogen (NO3 + NO2, total phosphorous (TP, and total organic carbon (TOC through the largest river swamp basin in North America. The study found that, over the past 27 years, the Atchafalaya River Basin (ARB acted as a significant sink for TKN (annual retention: 24%, TP (41%, and TOC (12%, but a source for NO3 + NO2 nitrogen (6%. On an annual basis, ARB retained 48,500 t TKN, 16,900 t TP, and 167,100 t TOC from the river water. The retention rates were closely and positively related to the river discharge with highs during the winter and spring and lows in the late summer. The higher NO3 + NO2 mass outflow occurred throughout spring and summer, indicating an active role of biological processes on nitrogen as water and air temperatures in the basin rise.

  2. Spreading rate dependent seafloor deformation in response to India-Eurasia collision: results of a hydrosweep survey in the Central Indian Ocean basin

    Digital Repository Service at National Institute of Oceanography (India)

    Mukhopadhyay, R.; George, P.; Ranade, G.

    ; spreading rate dependence; effect of plate collision; stress regime; CIOB 1. Introduction The Central Indian Ocean Basin (CIOB) is the largest basin in the Indian Ocean, and covers an area of about 7 million km2 (Fig. la). This basin is underlain... from the central part of the CIOB (Kamesh Raju and Ramprasad, 1989; Mukhopadhyay and Khadge, 1992, 1994; Kodagali et al., 1992) call for a thorough analysis of the effect of the stress regime (Weissel et al., 1980; Zoback et al., 1989...

  3. A note on chemical composition and origin of ferromanganese oxide coated and uncoated pumice samples from central Indian Ocean basin

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Parthiban, G.; Moraes, C.; Rajalakshmi, R.; Lekshmi, S.; Athira, S.; JaiSankar, S.

    Pumice are explosive volcanic product, occur as uncoated or coated with ferromanganese (Fe-Mn) oxide and resides in association with ferromanganese nodules on the seabed in Central Indian Ocean Basin (CIOB). The older Fe-Mn oxide coated and younger...

  4. Coexistence of pumice and manganese nodule fields-evidence for submarine silicic volcanism in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Sudhakar, M.

    Pumice, of various shapes and sizes, uncoated or coatEd. by ferromanganese oxides, have been recovered from deeper parts of the Central Indian Basin (CIB). The pumice field covers an area of 600,000 km sup(2), approximately encompassing one...

  5. Depositional history and clay minerals of the Upper Cretaceous basin in the South-Central Pyrenees, Spain

    NARCIS (Netherlands)

    Nagtegaal, P.J.C.

    1972-01-01

    An ordered sequence of well-defined sedimentary environments reflects the deepening and shallowing stages in the depositional history of the Upper Cretaceous basin in the South-Central Pyrenees, Spain. The sequence, which has a Santonian age at its base, starts with a calcarenite barrier system on w

  6. The ant (Hymenoptera: Formicidae) fauna of the cedar glades and xeric limestone prairies of the Central Basin of Tennessee

    Science.gov (United States)

    Ants may be the most thoroughly documented group of insects inhabiting the cedar glades of the Central Basin of Tennessee with two studies conducted in the late 1930s reporting ants found in cedar glades of the region. To compare the ant fauna of modern cedar glades with the lists produced in earlie...

  7. Coarse fraction components in a red-clay sedimemt core, Central Indian Ocean Basin: Their occurrence and significance

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Fernandes, G.Q.; Mahender, K.

    Coarse Fractions Components of a sediment core (268 cm from a water depth of 5120 m) collected at 18 degrees S and 80 degrees E from the red clay domain in the Central Indian Ocean Basin (CIOB), comprises mineral grains, basaltic fragments...

  8. Mineral chemistry, bulk composition and source of the ferromanganese nodules nuclei from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R.; Miura, H.

    Nuclei of ferromanganses nodules from the Central Indian Ocean Basin show the presence of abundant plagioclase feldspars (1-3 mm diameter). They are indentified as calcic plagioclase (peak at 3.20 A). Plagioclase chemical composition (CaO 6...

  9. A Literature Review of Archaeological, Historical, and Paleontological Resources of the Sheyenne River Basin in North Dakota

    Science.gov (United States)

    1977-01-01

    Archaeology, Lithic Analysis , North American Indians, Culture Change, Archaeological Methods. POSITIONS: Assistant Professor, University of Wisconsin- La Crosse...American Indians. W- ,1W’ ejj V : RESEARCH INTERESTS: Plains Prehistory (specifically Southern and Central Plains), Lithic Analysis , Early Man in the New

  10. Provenance analysis of the Guaritas Group (RS conglomeratic sandstones: implications for the paleoclimate and paleogeography of the Eocambrian Central Camaquã sub-basin

    Directory of Open Access Journals (Sweden)

    Antonio Romalino Santos Fragoso-Cesar

    2013-06-01

    Full Text Available The Camaquã Supergroup, located in the central-south region of Rio Grande do Sul, Brazil, constitutes a rift-type post-orogenicsedimentary basin, whose deposition occurred in a continental environment between the Ediacaran and the Eocambrian.The upper succession of the Camaquã Supergroup is represented by the Guaritas Group, a unit formed by fluvial, eolian andalluvial fan deposits that keeps important records of the sedimentation right after the end of the neoproterozoic orogenesis thatgave rise to the Gondwana supercontinent. The objective of the present work was to apply sedimentary provenance analysis inconglomeratic arenites and conglomerates of the Guaritas Group, in order to explore the climatic and tectonic evolution historyof this unit. Based on the pebble compositional data, two main source areas were recognized for the deposits of this unit,a more distal one located to the north, related with a trunk river system parallel to the basin main axis, and a more proximalone located to the east, related to transversal fluvial systems and alluvial fans at the border of the basin. The comparison of theprovenance data with previous studies on facies and paleocurrents suggests that, during the entire evolution of the east borderof the basin, there was a same transversal fluvial system, whose catchment area suffered significative reductions due to thereactivation of the east border fault during the deposition of the Varzinha and Pedra Pintada Formations. The Serra do ApertadoFormation, the upper unit of Guaritas Group, shows a high correlation between the variation of quartzose and non quartzosepebbles composition, and it was attributed to a variation between more humid and more arid climatic conditions.

  11. Morphostructural characterization of the Charco basin and its surrounding areas in the Chihuahua segment of north Mexican Basin and Range Province

    Science.gov (United States)

    Troiani, Francesco; Menichetti, Marco

    2014-05-01

    The Chihuahua Basin and Range (CBR) is the eastern branch of the northern Mexican Basin and Range Province that, from a morphostructural point of view, presently is one amongst the lesser-known zones of the southern portion of the North America Basin and Range Province. The study area covers an approximately 800 km2-wide portion of the CBR and encompasses the fault-bounded Charco basin and its surrounding areas. The bedrock of the area pertains to the large siliceous-igneous province of the Sierra Madre Occidental and consists of volcanoclastic rocks including Oligocene dacite, rhyolite, rhyolitic tuffs, and polimitic conglomerates. The region is characterized by a series of NW-SE oriented valleys delimited by tilted monoclinal blocks bounded by high angle, SW-dipping, normal faults. Abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins are the main morphological elements of the area. The valleys correspond to structural grabens filled with Plio-Pleistocene continental sediments. These grabens are about 10 km wide, while the extensional fault system extend over a distance of more than 15 km. The mountain ranges are in most cases continuous over distances that range from 10 to 70 km including different branches of the extensional and transfer faults. The morphogenesis is mainly erosive in character: erosional landforms (such as rocky scarps, ridges, strath-terraces, erosional pediment, reverse slopes, landslide scar zones, litho-structural flat surfaces) dominate the landscape. In contrast, Quaternary depositional landforms are mainly concentrated within the flat valleys or basins. The Quaternary deposits consist of wide alluvial fans extending to the foot of the main ridges, fluvial and debris-slope deposits. The morphostructural characterization of the area integrated different methodologies, including: i) geomorphological and structural field analyses; ii) remote sensing and geo-morphometric investigations

  12. Monitoring and Modelling Glacier Melt and Runoff on Juncal Norte Glacier, Aconcagua River Basin, Central Chile

    Science.gov (United States)

    Pellicciotti, F.; Helbing, J. F.; Araos, J.; Favier, V.; Rivera, A.; Corripio, J.; Sicart, J. M.

    2006-12-01

    Results from a recent glacio-meteorological experiment on the Juncal Norte glacier, in central Chile, are presented. Melt water is a crucial resource in the Central Andes, as it provides drinking water, water for agriculture and for industrial uses. There is also increasing competition for water use and allocation, as water demands from mining and industry are rising. Assessing water availability in this region and its relation with climatic variations is therefore crucial. The Dry Central Andes are characterised by a climatic setting different from that of the Alps and the subtropical Andes of Bolivia and Peru. Summers are very dry and stable, with precipitation close to zero and low relative humidity. Solar radiation is very intense, and plays a key role in the energy balance of snow covers and glaciers. The main aim of this study is to investigate the glacier-climate interaction in this area, with particular attention devoted to advanced modelling techniques for the spatial redistribution of meteorological variables, in order to gain an accurate picture of the ablation processes typical of these latitudes. During the ablation season 2005/2006, an extensive field campaign was conducted on the Juncal Norte glacier, aimed at monitoring the melt and runoff generation processes on this remote glacier in the dry Andes. Melt rates, runoff at the snout, meteorological variables over and near the glacier, GPS data and glacier topography were recorded over the entire ablation season. Using this extensive and accurate data set, the spatial and temporal variability of the meteorological variables that drive the melt process on the glacier is investigated, together with the process of runoff generation. An energy balance model is used to simulate melt across the glacier, and special attention is devoted to the modelling of the solar radiation energy flux. The components of the energy balance are compared with those of Alpine basins. The validity of parameterisations of the

  13. The late Holocene dry period: multiproxy evidence for an extended drought between 2800 and 1850 cal yr BP across the central Great Basin, USA

    Science.gov (United States)

    Mensing, Scott A.; Sharpe, Saxon E.; Tunno, Irene; Sada, Don W.; Thomas, Jim M.; Starratt, Scott W.; Smith, Jeremy

    2013-01-01

    Evidence of a multi-centennial scale dry period between ∼2800 and 1850 cal yr BP is documented by pollen, mollusks, diatoms, and sediment in spring sediments from Stonehouse Meadow in Spring Valley, eastern central Nevada, U.S. We refer to this period as the Late Holocene Dry Period. Based on sediment recovered, Stonehouse Meadow was either absent or severely restricted in size at ∼8000 cal yr BP. Beginning ∼7500 cal yr BP, the meadow became established and persisted to ∼3000 cal yr BP when it began to dry. Comparison of the timing of this late Holocene drought record to multiple records extending from the eastern Sierra Nevada across the central Great Basin to the Great Salt Lake support the interpretation that this dry period was regional. The beginning and ending dates vary among sites, but all sites record multiple centuries of dry climate between 2500 and 1900 cal yr BP. This duration makes it the longest persistent dry period within the late Holocene. In contrast, sites in the northern Great Basin record either no clear evidence of drought, or have wetter than average climate during this period, suggesting that the northern boundary between wet and dry climates may have been between about 40° and 42° N latitude. This dry in the southwest and wet in the northwest precipitation pattern across the Great Basin is supported by large-scale spatial climate pattern hypotheses involving ENSO, PDO, AMO, and the position of the Aleutian Low and North Pacific High, particularly during winter.

  14. Effectiveness of two common antivenoms for North, Central, and South American Micrurus envenomations.

    Science.gov (United States)

    de Roodt, Adolfo R; Paniagua-Solis, Jorge F; Dolab, Jorge A; Estévez-Ramiréz, Judith; Ramos-Cerrillo, Blanca; Litwin, Silvana; Dokmetjian, José C; Alagón, Alejandro

    2004-01-01

    Micrurus snakes (coral snakes) may produce severe envenomation that can lead to death by peripheral respiratory paralysis. Only few laboratories produce specific antivenoms, and despite the cross-reactivity found in some Micrurus species venoms, the treatment is not always effective. To test two therapeutic antivenoms against the venom of four species of Micrurus from Southern America, North of South America, Central America, and North America, the determination of the lethal potency of the venoms, the study of some biochemical and immunochemical characteristics, and the determination of the neutralizing activity of both antivenoms were studied. North American and South American antivenoms neutralized well venoms from Micrurus species of the corresponding hemisphere but displayed lower effectiveness against venoms of species from different hemispheres. It was concluded that the neutralization of Micrurus venoms by regional antivenoms could be useful to treat the envenomation by some Micrurus snakes but is necessary to evaluate carefully the antivenoms to be used with the venoms from the snakes of the region. Also, considering the difficulties for coral snake antivenom production, the development of a polyvalent antivenom is useful to treat the envenomation by coral snakes from different regions is necessary.

  15. Neospora caninum infection in beef cattle reared under grazing conditions in north-central Mexico

    Directory of Open Access Journals (Sweden)

    Karina Mondragón-Zavala

    2011-05-01

    Full Text Available Objetive. To determine the seroprevalence of N. caninum antibodies and prevalence of parasite DNA in blood, and estimate the association between seroprevalence and the potential risk of some factors in beef cattle under grazing conditions in north-central Mexico. Materials and methods. Blood samples from 139 cows and only 10 bulls belonging to 13 farms were collected and evaluated by ELISA test to detect antibodies against N. caninum. Furthermore, to determine the presence of parasite DNA, nested PCR probe was performed on blood samples. Association between potential risk factors and seroprevalence was estimated. Results. Overall seroprevalence was 23% (35/149 samples, while the prevalence of parasite DNA in blood was 28% (42/149 samples. Of the 149 animals examined 28 (19% were positive to both tests (25 cows and 3 bulls. Concordance between tests was k = 0.63. All herds had seropositive animals with positive parasite DNA detection in blood. The only risk factor identified was the presence of dogs (OR= 2.65. Conclusions. This study showed that bovine neospososis should be considered as an important infectious disease in north-central Mexico herds. Therefore, an epidemiological control should be taken into consideration to avoid the negative effect of this disease on mexican beef industry.

  16. Forest Owners’ Organizations in North and Central Portugal – Assessment of Success

    Directory of Open Access Journals (Sweden)

    Diana Feliciano

    2011-06-01

    Full Text Available Background and Purpose: The emergence of forest owners’ organizations (FOOs in Portugal occurred in the 1990s. Fifteen years later there were 173 FOOs providing services to the private forest owners and also to the whole of society. This study aims to evaluate the success of FOOs in increasing their membership and the quantity of services provided. Material and Methods: Eight FOOs from the North and Central Portugal were chosen as case studies. Quantitative data on membership numbers and number of services provided by the eight case studies were collected from the archives of FORESTIS or directly at the FOOs headquarters. Qualitative data from newsletters, annual reports, local newspapers and letters were also collected to be further analysed. Secondary data collected cover a period of ten years (1994-2005. In addition, eight interviews to members of staff or FOOs directors were conducted in 2005. It was hypothesised that the number of members and the quantity of services provided may be interrelated and that the turnover of staff and their productivity influence the success of FOOs in increasing their membership and providing technical advice services. Results and Conclusion: The study showed that although most FOOs were successful in making their membership grow, there were big differences in the number of members, in the forest area covered by them and in the quantity of services provided. It was concluded that human capital, financial capital and path dependence were the factors that most constrained the success FOOs in North and Central Portugal.

  17. A synoptic climatology of derecho producing mesoscale convective systems in the North-Central Plains

    Science.gov (United States)

    Bentley, Mace L.; Mote, Thomas L.; Byrd, Stephen F.

    2000-09-01

    Synoptic-scale environments favourable for producing derechos, or widespread convectively induced windstorms, in the North-Central Plains are examined with the goal of providing pattern-recognition/diagnosis techniques. Fifteen derechos were identified across the North-Central Plains region during 1986-1995. The synoptic environment at the initiation, mid-point and decay of each derecho was then evaluated using surface, upper-air and National Center for Atmospheric Research (NCAR)/National Center for Environmental Prediction (NCEP) reanalysis datasets.Results suggest that the synoptic environment is critical in maintaining derecho producing mesoscale convective systems (DMCSs). The synoptic environment in place downstream of the MCS initiation region determines the movement and potential strength of the system. Circulation around surface low pressure increased the instability gradient and maximized leading edge convergence in the initiation region of nearly all events regardless of DMCS location or movement. Other commonalities in the environments of these events include the presence of a weak thermal boundary, high convective instability and a layer of dry low-to-mid-tropospheric air. Of the two corridors sampled, northeastward moving derechos tend to initiate east of synoptic-scale troughs, while southeastward moving derechos form on the northeast periphery of a synoptic-scale ridge. Other differences between these two DMCS events are also discussed.

  18. CULTURAL TOURISM POTENTIAL IN THE NORTH CENTRAL PROVINCE OF SRI LANKA

    Directory of Open Access Journals (Sweden)

    Wijitapure Wimalaratana

    2016-04-01

    Full Text Available International tourism has recorded a tremendous growth in the past and this trend will continue further uninterruptedly. Sri Lanka has been one of the major tourist attractions since antiquity. The end of a protracted civil war has been a blessing for the tourist industry and the consequent rapid expansion of tourist infrastructure in the island. Although the island is a small one, it is rich in religious and cultural diversity. Buddhism is the main religion of the majority of people, while Hinduism, Christianity and Islam are also practiced by portions of the population. The resultant rich cultural heritage of the island has been constructed around religious practices, historical monuments and ancient cities, meditation, yoga, folk music and dances, festivities, ceremonies and rituals. Special sites with multi religious attractions reflect the diversity and uniqueness of a rich culture. The North Central Province of Sri Lanka is especially rich in cultural resources owing largely to it housing two cities that served as the island’s capital for more than 1000 years in ancient times. Only a small fraction of this vast amount of resources has been utilized by the tourism industry so far. The paper argues that the promotion of religious and cultural tourism products in the North Central Province of Sri Lanka will open up new avenues of engagement for tourists and income generation for the island. Ancient monuments and religious sites, segments of culture tourism, would be magnates to overseas archeologists and Buddhist communities.

  19. Use of bioindicators and passive sampling devices to evaluate ambient ozone concentrations in north central Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    Yuska, D.E.; Skelly, J.M.; Ferdinand, J.A.; Stevenson, R.E.; Savage, J.E.; Mulik, J.D.; Hines, A

    2003-09-01

    Passive samplers and bioindicator plants detect ozone air pollution in north central Pennsylvania. - Ambient concentrations of tropospheric ozone and ozone-induced injury to black cherry (Prunus serotina) and common milkweed (Asclepias syriaca) were determined in north central Pennsylvania from 29 May to 5 September 2000 and from 28 May to 18 September 2001. Ogawa passive ozone samplers were utilized within openings at 15 forested sites of which six were co-located with TECO model 49 continuous ozone monitors. A significant positive correlation was observed between the Ogawa passive samplers and the TECO model 49 continuous ozone monitors for the 2000 (r=0.959) and 2001 (r=0.979) seasons. In addition, a significant positive correlation existed in 2000 and 2001 between ozone concentration and elevation (r=0.720) and (r=0.802), respectively. Classic ozone-induced symptoms were observed on black cherry and common milkweed. In 2000, initial injury was observed in early June, whereas for the 2001 season, initial injury was initially observed in late June. During both seasons, injury was noted at most sites by mid- to late-July. Soil moisture potential was measured for the 2001 season and a significant positive relationship (P<0.001) showed that injury to black cherry was a function of cumulative ozone concentrations and available soil moisture.

  20. Optimum combination of water drainage, water supply and eco-environment protection in coal-accumulated basin of North China

    Institute of Scientific and Technical Information of China (English)

    武强; 董东林; 石占华; 武雄; 孙卫东; 叶责钧; 李树文; 刘金韬

    2000-01-01

    The conflict among water drainage, water supply and eco-environment protection is getting more and more serious due to the irrational drainage and exploitation of ground water resources in coal-accumulated basins of North China. Efficient solutions to the conflict are to maintain long-term dynamic balance between input and output of the ground water basins, and to try to improve resourcification of the mine water. All solutions must guarantee the eco-environment quality. This paper presents a new idea of optimum combination of water drainage, water supply and eco-environment protection so as to solve the problem of unstable mine water supply, which is caused by the changeable water drainage for the whole combination system. Both the management of hydraulic techniques and constraints in economy, society, ecology, environment, industrial structural adjustments and sustainable developments have been taken into account. Since the traditional and separate management of different departments of water drainage,

  1. Factors controlling the sedimentary evolution of the Kimmeridgian ramp in the north Iberian Basin (NE Spain

    Directory of Open Access Journals (Sweden)

    Bádenas, B.

    1994-04-01

    Full Text Available The aim of this paper is to summarize the present knowledge reached by the authors on the carbonate ramp which developed in the iberian basin during Kimmeridgian times. Our results were obtained from a combined field analysis and computer modelling carried out in the north Iberian Chain (NE Spain. Extensive field analysis in the Ricia area (Zaragoza, NE Spain, resulted in a detailed mapping of the transition from inner to outerramp facies on this carbonate rampo Three facies belts may be distinguished in this rampo The outer ramp facies consists of marls and mudstones rhythmic facies. The inner ramp facies, located aboye fair-weather wave base, are dominated by coral patch reef growing. The middle ramp facies are represented by marls and micrites bearing skeletal and oolitic tempestite levels which sharply grade into high-amplitude o'olitic sandwave. Factors such as resedimentation by storms, carbonate production and relative variation of sea level acting in the Kimmeridgian ramp are also quantiphied and discussed. Most of the mud accumulated in outer-ramp areas was produced in the coral «carbonate factory» located in inner areas. Off-shore resedimentation by storm was the main agent of basinward transport of this mudo The deduced accommodation curve consists of three elements: a linear rise which satisfactorily matches the normal subsidence figures observed in intracratonic basins; a third-order cycle, that may have a regional cause and higher order cycles in the Milanckovich band, that may be eustatic in origin.La sedimentación en la cuenca ibérica septentrional durante el Kimmeridgiense tuvo lugar en una extensa rampa carbonatada de bajo ángulo. Las facies de rampa externa, acumuladas por debajo del nivel de base del oleaje debido a tormentas (i.e., C. 50 to 80 m de profundidad, están formadas por una ritmita de margas y calizas (i.e., Fm Loriguilla. Las facies de rampa interna, localizadas por encima del nivel de base del oleaje de

  2. Improved Algorithm of SCS-CN Model Parameters in Typical Inland River Basin in Central Asia

    Science.gov (United States)

    Wang, Jin J.; Ding, Jian L.; Zhang, Zhe; Chen, Wen Q.

    2017-02-01

    Rainfall-runoff relationship is the most important factor for hydrological structures, social and economic development on the background of global warmer, especially in arid regions. The aim of this paper is find the suitable method to simulate the runoff in arid area. The Soil Conservation Service Curve Number (SCS-CN) is the most popular and widely applied model for direct runoff estimation. In this paper, we will focus on Wen-quan Basin in source regions of Boertala River. It is a typical valley of inland in Central Asia. First time to use the 16m resolution remote sensing image about high-definition earth observation satellite “Gaofen-1” to provide a high degree accuracy data for land use classification determine the curve number. Use surface temperature/vegetation index (TS/VI) construct 2D scatter plot combine with the soil moisture absorption balance principle calculate the moisture-holding capacity of soil. Using original and parameter algorithm improved SCS-CN model respectively to simulation the runoff. The simulation results show that the improved model is better than original model. Both of them in calibration and validation periods Nash-Sutcliffe efficiency were 0.79, 0.71 and 0.66,038. And relative error were3%, 12% and 17%, 27%. It shows that the simulation accuracy should be further improved and using remote sensing information technology to improve the basic geographic data for the hydrological model has the following advantages: 1) Remote sensing data having a planar characteristic, comprehensive and representative. 2) To get around the bottleneck about lack of data, provide reference to simulation the runoff in similar basin conditions and data-lacking regions.

  3. Simulation of groundwater flow and the interaction of groundwater and surface water in the Willamette Basin and Central Willamette subbasin, Oregon

    Science.gov (United States)

    Herrera, Nora B.; Burns, Erick R.; Conlon, Terrence D.

    2014-01-01

    Full appropriation of tributary streamflow during summer, a growing population, and agricultural needs are increasing the demand for groundwater in the Willamette Basin. Greater groundwater use could diminish streamflow and create seasonal and long-term declines in groundwater levels. The U.S. Geological Survey (USGS) and the Oregon Water Resources Department (OWRD) cooperated in a study to develop a conceptual and quantitative understanding of the groundwater-flow system of the Willamette Basin with an emphasis on the Central Willamette subbasin. This final report from the cooperative study describes numerical models of the regional and local groundwater-flow systems and evaluates the effects of pumping on groundwater and surface‑water resources. The models described in this report can be used to evaluate spatial and temporal effects of pumping on groundwater, base flow, and stream capture. The regional model covers about 6,700 square miles of the 12,000-square mile Willamette and Sandy River drainage basins in northwestern Oregon—referred to as the Willamette Basin in this report. The Willamette Basin is a topographic and structural trough that lies between the Coast Range and the Cascade Range and is divided into five sedimentary subbasins underlain and separated by basalts of the Columbia River Basalt Group (Columbia River basalt) that crop out as local uplands. From north to south, these five subbasins are the Portland subbasin, the Tualatin subbasin, the Central Willamette subbasin, the Stayton subbasin, and the Southern Willamette subbasin. Recharge in the Willamette Basin is primarily from precipitation in the uplands of the Cascade Range, Coast Range, and western Cascades areas. Groundwater moves downward and laterally through sedimentary or basalt units until it discharges locally to wells, evapotranspiration, or streams. Mean annual groundwater withdrawal for water years 1995 and 1996 was about 400 cubic feet per second; irrigation withdrawals

  4. A key continental archive for the last 2 Ma of climatic history of the central Mediterranean region: A pilot drilling in the Fucino Basin, central Italy

    Science.gov (United States)

    Giaccio, B.; Regattieri, E.; Zanchetta, G.; Wagner, B.; Galli, P.; Mannella, G.; Niespolo, E.; Peronace, E.; Renne, P. R.; Nomade, S.; Cavinato, G. P.; Messina, P.; Sposato, A.; Boschi, C.; Florindo, F.; Marra, F.; Sadori, L.

    2015-12-01

    An 82 m long sedimentary succession was retrieved from the Fucino Basin, the largest intermountain tectonic depression of the central Apennines. The basin hosts a succession of fine-grained lacustrine sediments (ca. 900 m-thick) possibly continuously spanning the last 2 Ma. A preliminary tephrostratigraphy study allows us to ascribe the drilled 82 m long record to the last 180 ka. Multi-proxy geochemical analyses (XRF scanning, total organic/inorganic carbon, nitrogen and sulfur, oxygen isotopes) reveal noticeable variations, which are interpreted as paleohydrological and paleoenvironmental expressions related to classical glacial-interglacial cycles from the marine isotope stage (MIS) 6 to present day. In light of the preliminary results, the Fucino sedimentary succession is likely to provide a long, continuous, sensitive, and independently dated paleoclimatic archive of the central Mediterranean area.

  5. Hydrological impact of rainwater harvesting in the Modder river basin of central South Africa

    Directory of Open Access Journals (Sweden)

    W. A. Welderufael

    2011-05-01

    Full Text Available Along the path of water flowing in a river basin are many water-related human interventions that modify the natural systems. Rainwater harvesting is one such intervention that involves harnessing of water in the upstream catchment. Increased water usage at upstream level is an issue of concern for downstream water availability to sustain ecosystem services. The upstream Modder River basin, located in a semi arid region in the central South Africa, is experiencing intermittent meteorological droughts causing water shortages for agriculture, livestock and domestic purpose. To address this problem a technique was developed for small scale farmers with the objective of harnessing rainwater for crop production. However, the hydrological impact of a wider adoption of this technique by farmers has not been well quantified. In this regard, the SWAT hydrological model was used to simulate the hydrological impact of such practices. The scenarios studied were: (1 Baseline scenario, based on the actual land use of 2000, which is dominated by pasture (combination of natural and some improved grass lands (PAST; (2 Partial conversion of Land use 2000 (PAST to conventional agriculture (Agri-CON; and (3 Partial conversion of Land use 2000 (PAST to in-field rainwater harvesting which was aimed at improving the precipitation use efficiency (Agri-IRWH.

    SWAT was calibrated using observed daily mean stream flow data of a sub-catchment (419 km2 in the study area. SWAT performed well in simulating the stream flow giving Nash and Sutcliffe (1970 efficiency index of 0.57 for the monthly stream flow calibration. The simulated water balance results showed that the highest peak mean monthly direct flow was obtained on Agri-CON land use (18 mm, followed by PAST (12 mm and Agri-IRWH land use (9 mm. These were 19 %, 13 % and 11 % of the mean annual rainfall, respectively. The Agri-IRWH scenario reduced direct flow by 38 % compared to Agri-CON. On the other

  6. Regional implications of new chronostratigraphic and paleogeographic data from the Early Permian Darwin Basin, east-central California

    Science.gov (United States)

    Stevens, Calvin H.; Stone, Paul; Magginetti, Robert T.

    2015-01-01

    The Darwin Basin developed in response to episodic subsidence of the western margin of the Cordilleran continental shelf from Late Pennsylvanian (Gzhelian) to Early Permian (late Artinskian) time. Subsidence of the basin was initiated in response to continental truncation farther to the west and was later augmented by thrust emplacement of the Last Chance allochthon. This deep-water basin was filled by voluminous fine-grained siliciclastic turbidites and coarse-grained limestone-gravity-flow deposits. Most of this sediment was derived from the Bird Spring carbonate shelf and cratonal platform to the northeast or east, but some came from an offshore tectonic ridge (Conglomerate Mesa Uplift) to the west that formed at the toe of the Last Chance allochthon. At one point in the late Artinskian the influx of extrabasinal sediment was temporarily cut off, resulting in deposition of a unique black limestone that allows precise correlation throughout the basin. Deep-water sedimentation in the Darwin Basin ended by Kungurian time when complex shallow-water to continental sedimentary facies spread across the region. Major expansion of the Darwin Basin occurred soon after the middle Sakmarian emplacement of the Last Chance allochthon. This tectonic event was approximately coeval with deformation in northeastern Nevada that formed the deep-water Dry Mountain Trough. We herein interpret the two basins to have been structurally continuous. Deposition of the unique black limestone is interpreted to mark a eustatic sea level rise that also can be recognized in Lower Permian sections in east-central Nevada and central Arizona.

  7. Preliminary interpretation of industry two-dimensional seismic data from Susitna Basin, south-central Alaska

    Science.gov (United States)

    Lewis, Kristen A.; Potter, Christopher J.; Shah, Anjana K.; Stanley, Richard G.; Haeussler, Peter J.; Saltus, Richard W.

    2015-07-30

    Located approximately 80 kilometers northwest of Anchorage, Alaska, the Susitna Basin is a complex sedimentary basin whose tectonic history has been poorly understood. Recent interpretation of two-dimensional seismic reflection data integrated with well, aeromagnetic, and gravity data provides new insights into the structural and stratigraphic nature of the basin.

  8. Investigaton of ÇINARCIK Basin and North Anatolian Fault Within the Sea of Marmara with Multichannel Seismic Reflection Data

    Science.gov (United States)

    Atgın, O.; Çifçi, G.; Sorlien, C.; Seeber, L.; Steckler, M.; Sillington, D.; Kurt, H.; Dondurur, D.; Okay, S.; Gürçay, S.; Sarıtaş, H.; Küçük, H. M.

    2012-04-01

    The Sea of Marmara is becoming a natural laboratory for structure, sedimentation, and fluid flow within the North Anatolian fault (NAF) system. Much marine geological and geophysical data has been collected there since the deadly 1999 M=7.2. Izmit earthquake. The Sea of Marmara occupies 3 major basins, with the study area located in the eastern Cinarcik basin near Istanbul. These basins are the results of an extensional component in releasing segments between bends in this right-lateral tranmsform. It is controversial whether the extensional component is taken up by partitioned normal slip on separate faults, or instead by oblique right-normal slip on the non-vertical main northern branch of the NAF. High resolution multichannel seismic reflection (MCS) and multibeam bathymetry data collected by R/V K.Piri Reis and R/V Le-Suroit as part of two different projects respectively entitled "SeisMarmara", "TAMAM" and "ESONET". 3000 km of multichannel seismic reflection profiles were collected in 2008 and 2010 using 72, 111, and 240 channels of streamer with a 6.25 m group interval. The generator-injector airgun was fired every 12.5 or 18.75 m and the resulting MCS data has 10-230 Hz frequency band. The aim of the study is to investigate continuation of North Anatolian Fault along the Sea of Marmara, in order to investigate migration of depo-centers past a fault bend. We also test and extend a recently-published age model, quantify extension across short normal faults, and investigate whether a major surface fault exists along the southern edge of Çınarcık Basin. MCS profiles indicate that main NAF strand is located at the northern boundary of Çınarcık Basin and has a large vertical component of slip. The geometry of the eastern (Tuzla) bend and estimated right-lateral slip rates from GPS data requires as much of ten mm/yr of extension across Çınarcık Basin. Based on the published age model, we calculate about 2 mm/yr of extension on short normal faults in the

  9. Overpressure development and oil charging in the central Junggar Basin,Northwest China:Implication for petroleum exploration

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Junggar Basin is one of the largest and most petroliferous superimposed petroleum basins in China. The central depression area has become the frontier field for petroleum exploration. The characteristics of potential source rocks and reservoir sandstones, and the pressure regime in the central Junggar Basin were studied. Permian shales are dominated by hydrogen-rich, oil-prone algal organic matter, and Jurassic mudstones are dominated by hydrogen-poor, higher-plant derived organic matter. These source rocks are widespread and have been mature for hydrocarbon generation, suggesting good to excellent exploration potential, both for crude oils and for natural gases. The deeply buried Jurassic sandstones usually have low porosity and permeability. However, sandstones beneath the Jurassic/Cretaceous unconformity display relatively high porosity and permeability, suggesting that meteoric water leaching had improved the quality of the sandstones. Overpressure developed over much of the central Junggar Basin. The overpressured rocks are characterized by slightly increased interval transit time, low sandstone permeability, increased organic matter maturity, and high relative hydrocarbon-gas contents. Mudstones in the overpressured system have quite the same clay mineral compositions as mudstones in the lower part of the normally pressured system. Overpressure generation in the central Junggar Basin is best to be explained as the result of hydrocarbon generation and fluid retention in low-permeability rocks. Petroleum generated from Permian and Jurassic source rocks could migrate laterally through preferential petroleum migration pathways and accumulated in structural traps or lithological traps in the overpressured system, or migrate vertically through faults/ hydraulic fractures into the overlying, normally pressured system and accumulate in structural or lithological traps. Therefore, commercial petroleum reservoirs could be potentially found in both the overpressured

  10. Overpressure development and oil charging in the central Junggar Basin,Northwest China:Implication for petroleum exploration

    Institute of Scientific and Technical Information of China (English)

    CAI XiYuan

    2009-01-01

    The Junggar Basin is one of the largest and most petroliferous superimposed petroleum basins in China.The central depression area has become the frontier field for petroleum exploration.The characteristics of potential source rocks end reservoir sandstones,and the pressure regime in the central Junggar Basin were studied.Permian shales are dominated by hydrogen-rich,oil-prone algal organic matter,and Jurassic mudstones are dominated by hydrogen-poor,higher-plant derived organic matter.These source rocks are widespread and have been mature for hydrocarbon generation,suggesting good to excellent exploration potential,both for crude oils and for natural gases.The deeply buried Jurassic sandstones usually have low porosity and permeability.However,sandstones beneath the Jurassic/Cretaceous unconformity display relatively high porosity and permeability,suggesting that meteoric water leaching had improved the quality of the sandstones.Overpressure developed over much of the central Junggar Basin.The overpressured rocks are characterized by slightly increased interval transit time,low sandstone permeability,increased organic matter maturity,and high relative hydrocarbon-gas contents.Mudstones in the overpressured system have quite the same clay mineral compositions as mudstones in the lower part of the normally pressured system.Overpressure generation in the central Junggar Basin is best-to be explained as the result of hydrocarbon generation and fluid retention in low-permeability rocks.Petroleum generated from Permian and Jurassic source rocks could migrate laterally through preferential petroleum migration pathways and accumulated in structural traps or lithological traps in the overpressured system,or migrate vertically through faults/hydraulic fractures into the overlying,normally pressured system and accumulate in structural or lithological traps.Therefore,commercial petroleum reservoirs could be potentially found in both the overpressured system,and in the normally

  11. THE OLIGOCENE MOLLUSC FAUNA OF THE PIEDMONT BASIN (NORTH-WESTERN ITALY I. SCAPHOPODA AND ARCHAEOGASTROPODA

    Directory of Open Access Journals (Sweden)

    M. CRISTINA BONCI

    2000-07-01

    Full Text Available The aim of the present work is to study the Oligocene Scaphopoda and Archaeogastropoda of the Tertiary Piedmont Basin (T.P.B., aiming towards an overall revision of the Oligocene mollusc fauna of this Basin. Five taxa of Scaphopoda and twenty-eight taxa of Archaeogastropoda have been analysed; among these a new species of Nerita (Theliostyla is proposed. 

  12. Parascolymia (Scleractinia: Lobophylliidae in the Central Paratethys Sea (Vienna Basin, Austria and its possible biogeographic implications.

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    Markus Reuter

    Full Text Available Palaeobiogeographical and palaeodiversity patterns of scleractinian reef corals are generally biased due to uncertain taxonomy and a loss of taxonomic characters through dissolution and recrystallization of the skeletal aragonite in shallow marine limestones. Herein, we describe a fossil lobophylliid coral in mouldic preservation from the early middle Miocene Leitha Limestone of the Central Paratethys Sea (Vienna Basin, Austria. By using grey-scale image inversion and silicone rubber casts for the visualization of the original skeletal anatomy and the detection of distinct micromorphological characters (i.e. shape of septal teeth, granulation of septocostae Parascolymia bracherti has been identified as a new species in spite of the dissolved skeleton. In the recent era, Parascolymia like all Lobophylliidae is restricted to the Indo-Pacific region, where it is represented by a single species. The new species proves the genus also in the Miocene Mediterranean reef coral province. A review of the spatio-temporal relationships of fossil corals related to Parascolymia indicates that the genus was probably rooted in the Eastern Atlantic‒Western Tethys region during the Paleocene to Eocene and reached the Indo-Pacific region not before the Oligocene. The revealed palaeobiogeographical pattern shows an obvious congruence with that of Acropora and tridacnine bivalves reflecting a gradual equatorwards retreat of the marine biodiversity center parallel to the Cenozoic climate deterioration.

  13. Evolution of the Moxizhuang Oil Field, Central Junggar Basin, Northwest China

    Institute of Scientific and Technical Information of China (English)

    Zou Huayao; Zhang Yuanchun; Liu Jianzhang; Shi Jiannan

    2008-01-01

    Current oil saturation in the Moxizhuang (莫西庄) Oil Field in central Janggar (准噶尔) basin was evaluated by logging interpretation and measured on core samples, and the paleo-oil saturation in both the pay zones and water zones was investigated by graln-containing-oil inclusion (GOI) analysis.The pay zones in this field have low oil saturation and display low resistivity and small contrast between pay zones and water zones, and are classified as low-porosity, low oil saturation, and low resistivity reservoirs. Both the current low oil-saturation pay zones and the water zones above 4 365 m have high GOI values (up to 38%), suggesting high paleo-oil saturation. The significant difference between current oil saturation from both logging interpretation and core sample measurement and paleo-oil saturation indicated by GOI analysis suggests that this low oil-saturation field evolved from a high oil-saturation pool. Lateral re-migration and spill of formally trapped oil owing to changes in structural configuration since Neogene was the most plausible mechanism for oil loss in the Moxizhuang Oil Field.The combined effects of differential accumulation in the charge phase and the differential re-migration and spill of accumulated oil in Neogene are responsible for the complicated correlation between residual oil saturation and porosity/permeability of the reservoir sandstones and the distribution of low oil-saturation pay zones and paleo-oil zones (current water zones).

  14. Sedimentary characteristics of tide-dominated estuary in Donghetang Formation(Upper Devonian), central Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The Donghetang Formation (Upper Devonian) in central Tarim Basin has been thought an important oil and gas reservoir since the abundant oil and gas resources were found in the wells W16, W20, W34, and other fields. However, the sedimentary environment of the Donghetang Formation has been disputed because it suffered from both tidal and fluvial actions and there were not rich fossils in the sandstone. After the authors analyzed sedimentary features by means of drill cores, well logging data, paleosols, and with SEM obseruations, three kinds of sedimentary environments were distinguished: alluvial fan, tide-dominated estuary, and shelf. Particularly, the sedimentary features of tide-dominated estuary were studied in detail. Besides, the authors discussed sedimentary characteristics of the Donghetang Formation which was divided into two fourth-order sequences and five system tracts. At the same time, according to the forming process of five system tracts, the whole vertical evolution and lateral transition of tide-dominated estuary were illustrated clearly. Finally, the reservoir quality was evaluated based on porosity and permeability.

  15. Changes in Diversity of Fish Fauna of the Chu River Basin (Central Asia

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    Eleonora Byrlykzhanovna Kozhabaeva

    2015-11-01

    Full Text Available The Chu River originates in the Central Tien Shan Mountains and dissipates into the Muyunkum desert. The first information about the fish of the river was received in the middle 19-th century. Several expeditions collected data during 20-th century. Results of our investigations last decade in comparison with previous data allow tracking changes in the fish fauna after growing human impact. In the main, our data concern of the Kazakhstan part of the river. About 34 species and subspecies were discovered here; about 19 species between them are native. Origin or taxonomy of some species are disputable. In the last publications of the XX-th century 38 fish species and subspecies were mentioned. Native fish species as Aral barbel Barbus brachycephalus and Bulatmai barbel Barbus capito, Chu sharpray Capoetobrama kuschakewitschii and alien Sea trout Salmo trutta, Sevan trout Salmo ischchan were not found last decade in the Kazakhstan part of the river. Distribution area of native Balkhash marinka Schizothorax argentatus and alien Balkhash perch Perca schrenkii were reduced. The most widespread and numerous fish species are native roach, carp, dace, gudgeon and alien stone moroco. Native fishes like pike, asp, Aral ide, striped bystranka, golden spiny loach, southern ninespine stickleback and others were found only in certain sites. Fish species composition for each investigated site was not stable during recent years. Significant variations in fish composition were observed between different water bodies of the basin too. It reflects diversity of human impacts and unsteady water regimen here.

  16. Spatio-Temporal Variations and Source Apportionment of Water Pollution in Danjiangkou Reservoir Basin, Central China

    Directory of Open Access Journals (Sweden)

    Pan Chen

    2015-05-01

    Full Text Available Understanding the spatio-temporal variation and the potential source of water pollution could greatly improve our knowledge of human impacts on the environment. In this work, data of 11 water quality indices were collected during 2012–2014 at 10 monitoring sites in the mainstream and major tributaries of the Danjiangkou Reservoir Basin, Central China. The fuzzy comprehensive assessment (FCA, the cluster analysis (CA and the discriminant analysis (DA were used to assess the water pollution status and analyze its spatio-temporal variation. Ten sites were classified by the high pollution (HP region and the low pollution (LP region, while 12 months were divided into the wet season and the dry season. It was found that the HP region was mainly in the small tributaries with small drainage areas and low average annual discharges, and it was also found that most of these rivers went through urban areas with industrial and domestic sewages input into the water body. Principal component analysis/factor analysis (PCA/FA was applied to reveal potential pollution sources, whereas absolute principal component score-multiple linear regression (APCS-MLR was used to identify their contributions to each water quality variable. The study area was found as being generally affected by industrial and domestic sewage. Furthermore, the HP region was polluted by chemical industries, and the LP region was influenced by agricultural and livestock sewage.

  17. Hydrogeochemical investigations in a drained lake area: the case of Xynias basin (Central Greece).

    Science.gov (United States)

    Charizopoulos, Nikos; Zagana, Eleni; Stamatis, Georgios

    2016-08-01

    In Xynias drained Lake Basin's area, central Greece, a hydrogeochemical research took place including groundwater sampling from 30 sampling sites, chemical analysis, and statistical analysis. Groundwaters present Ca-Mg-HCO3 as the dominant hydrochemical type, while their majority is mixed waters with non-dominant ion. They are classified as moderately hard to hard and are characterized by oxidizing conditions. They are undersaturated with respect to gypsum, anhydrite, fluorite, siderite, and magnesite and oversaturated in respect to calcite, aragonite, and dolomite. Nitrate concentration ranges from 4.4 to 107.4 mg/L, meanwhile 13.3 % of the samples exceed the European Community (E.C.) drinking water permissible limit. The trace elements Fe, Ni, Cr, and Cd present values of 30, 80, 57, and 50 %, respectively, above the maximum permissible limit set by E.C. Accordingly, the majority of the groundwaters are considered unsuitable for drinking water needs. Sodium adsorption ratio values (0.04-3.98) and the electrical conductivity (227-1200 μS/cm) classify groundwaters as suitable for irrigation uses, presenting low risk and medium soil alkalization risk. Factor analysis shows that geogenic processes associated with the former lacustrine environment and anthropogenic influences with the use of fertilizers are the major factors that characterized the chemical composition of the groundwaters.

  18. Extension structural records in the Qinshui basin (North China) since the Late Mesozoic

    Science.gov (United States)

    Wang, Ying; Zhang, Qinglong; Zhu, Wenbin; Wang, Liangshu; Xie, Guoai; Liu, Chao; Zou, Xu

    2014-11-01

    Qinshui basin has abundant coal-bed methane resources and has been undergoing intensive intracontinental rifting and extensional tectonics since the Late Mesozoic. Some fractures, which were previously considered as conjugate shear fractures, are interpreted as joint sets with extension characteristics, for the first time in the Qinshui basin. The widely distributed joint sets with stable attitudes can be divided into four sets. This paper presents updated results of fault-slip datasets collected in different zones of the Qinshui basin and addresses the changes in the direction of extensional stresses since the Late Mesozoic. Based on the analysis results of the slickenline of normal faults, joint sets in the field, and focal mechanism solutions data from the Shanxi Province, we identified four main directions of extension since the Late Mesozoic in the Qinshui basin: (1) Early Cenozoic ENE-WSW (85 ± 15°) extension; (2) Palaeogene NNE-SSW (30 ± 5°) extension; (3) Miocene NW-SE (135 ± 15°) extension; and (4) Late Pliocene-quaternary NNW-SSE (170 ± 5°) extension. The principal extension directions in the Qinshui basin seem to have undergone a counterclockwise rotation from the Early Cenozoic to the Miocene. We prefer that the extension deformation events in the Qinshui basin since the Late Mesozoic were mainly related to the back-arc spreading induced by westward subduction of the paleo-Pacific plate under the Eurasian continent.

  19. HPHT reservoir evolution: a case study from Jade and Judy fields, Central Graben, UK North Sea

    Science.gov (United States)

    di Primio, Rolando; Neumann, Volkmar

    2008-09-01

    3D basin modelling of a study area in Quadrant 30, UK North Sea was performed in order to elucidate the burial, thermal, pressure and hydrocarbon generation, migration and accumulation history in the Jurassic and Triassic high pressure high temperature sequences. Calibration data, including reservoir temperatures, pressures, petroleum compositional data, vitrinite reflectance profiles and published fluid inclusion data were used to constrain model predictions. The comparison of different pressure generating processes indicated that only when gas generation is taken into account as a pressure generating mechanism, both the predicted present day as well as palaeo-pressure evolution matches the available calibration data. Compositional modelling of hydrocarbon generation, migration and accumulation also reproduced present and palaeo bulk fluid properties such as the reservoir fluid gas to oil ratios. The reconstruction of the filling histories of both reservoirs indicates that both were first charged around 100 Ma ago and contained initially a two-phase system in which gas dominated volumetrically. Upon burial reservoir fluid composition evolved to higher GORs and became undersaturated as a function of increasing pore pressure up to the present day situation. Our results indicate that gas compositions must be taken into account when calculating the volumetric effect of gas generation on overpressure.

  20. Ecological and environmental water demand of the lakes in the Haihe-Luanhe Basin of North China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe-Luanhe Basin of North China was analyzed. The calculating method of the ecological and environmental water demand of the lake basis on the water body and the calculating method of the ecological and environmental water demand of the lake basis on the aquatic ecosystem, wetland and vegetation were compared and discussed. As the examples of Baiyangdian Lake and Beidagang Lake in Haihe-Luanhe river basin, the ecological and environmental water demand of the two lakes was calculated to be 27× 108m3 . It is 6.75 times to the water demand according to the calculating method of the ecological and environmental water demand of the lake basis on the water body. The research result indicated: ( 1 ) The calculating methods of the ecological and environmental water demand of the lake basis on the aquatic ecosystem should be better than only basis on the water body of lake. (2) The data, such as area of the vegetation kind around and in the lake, the vegetation coefficient, the evaporating amount of the vegetation and the vegetation water demand itself around and in the lake are lack and urgent need. Some suggestions for controlling and regulating the water resource of the lake in North China were proposed.

  1. Water quality of Lake Arlington on Village Creek, north-central Texas; 1973 to 1981

    Science.gov (United States)

    Andrews, Freeman L.; Gibbons, Willard J.

    1983-01-01

    Water in Lake Arlington on Village Creek in north-central Texas had volume-weighted average concentrations of less than 240 milligrams per liter of dissolved solids, less than 30 milligrams per liter of dissolved chloride, and less than 40 milligrams per liter of dissolved sulfate between January 29, 1973, and August 20, 1981. The water was moderately hard (hardness greater than 60 but less than 120 milligrams per liter as calcium carbonate). The concentrations of each of these constituents were usually greatest during winter, especially during the first few years of the study, but decreased significantly as discharges of municipal wastes were systematically and progressively diverted to treatment facilities downstream from the reservoir.

  2. Influence of solar activity on the precipitation in the North-central China

    Science.gov (United States)

    Zhai, Qian

    2017-02-01

    The time series of sunspot number and the precipitation in the north-central China (108° ∼ 115° E, 33° ∼ 41° N) over the past 500 years (1470-2002) are investigated, through periodicity analysis, cross wavelet transform and ensemble empirical mode decomposition analysis. The results are as follows: the solar activity periods are determined in the precipitation time series of weak statistical significance, but are found in decomposed components of the series with statistically significance; the Quasi Biennial Oscillation (QBO) is determined to significantly exist in the time series, and its action on precipitation is opposite to the solar activity; the sun is inferred to act on precipitation in two ways, with one lagging the other by half of the solar activity period.

  3. Hydrology of Prairie Dog Creek Valley, Norton Dam to state line, north-central Kansas

    Science.gov (United States)

    Stullken, L.E.

    1984-01-01

    Development of water resources has been a major factor in the economy of Prairie Dog Creek Valley in north-central Kansas. Releases from Norton Reservoir to the Almena Irrigation District averaged 6,900 acre-feet per year during 1967-76. The number of irrigation wells increased from 4 to 147 during 1947-78. Ground water in the valley is derived mostly from the alluvial aquifer. The effects of irrigation on the aquifer are indicated by water-level changes. The water in storage increased from 130,000 to 136,000 acre-feet during 1947-78 due to recharge from surface-water irrigation. A steady-state model of the aquifer prior to irrigation (1947) indicated that most recharge was from precipitation (88 percent) and most discharge was to streams (54 percent) and reparian transpiration (26 percent). Although aquifer storage increased in this area, storage generally decreased in other areas of western Kansas. (USGS)

  4. Genetic Variation of Sclerotinia sclerotiorum from Multiple Crops in the North Central United States.

    Science.gov (United States)

    Aldrich-Wolfe, Laura; Travers, Steven; Nelson, Berlin D

    2015-01-01

    Sclerotinia sclerotiorum is an important pathogen of numerous crops in the North Central region of the United States. The objective of this study was to examine the genetic diversity of 145 isolates of the pathogen from multiple hosts in the region. Mycelial compatibility groups (MCG) and microsatellite haplotypes were determined and analyzed for standard estimates of population genetic diversity and the importance of host and distance for genetic variation was examined. MCG tests indicated there were 49 different MCGs in the population and 52 unique microsatellite haplotypes were identified. There was an association between MCG and haplotype such that isolates belonging to the same MCG either shared identical haplotypes or differed at no more than 2 of the 12 polymorphic loci. For the majority of isolates, there was a one-to-one correspondence between MCG and haplotype. Eleven MCGs shared haplotypes. A single haplotype was found to be prevalent throughout the region. The majority of genetic variation in the isolate collection was found within rather than among host crops, suggesting little genetic divergence of S. sclerotiorum among hosts. There was only weak evidence of isolation by distance. Pairwise population comparisons among isolates from canola, dry bean, soybean and sunflower suggested that gene flow between host-populations is more common for some crops than others. Analysis of linkage disequilibrium in the isolates from the four major crops indicated primarily clonal reproduction, but also evidence of genetic recombination for isolates from canola and sunflower. Accordingly, genetic diversity was highest for populations from canola and sunflower. Distribution of microsatellite haplotypes across the study region strongly suggest that specific haplotypes of S. sclerotiorum are often found on multiple crops, movement of individual haplotypes among crops is common and host identity is not a barrier to gene flow for S. sclerotiorum in the north central United

  5. Bedload exports in a forest catchment following wildfire and terracing, north-central Portugal

    Science.gov (United States)

    Martins, Martinho A. S.; Machado, Ana I.; Serpa, Dalila; Prats, Sergio A.; Faria, Sílvia R.; Varela, María E. T.; González-Pelayo, Óscar; Keizer, J. Jacob

    2014-05-01

    In Portugal, the occurrences of wildfires are frequently, on average, affects some 100.000 ha of rural lands each year, but in extreme years such as 2003 and 2005 the burnt areas can go over 300.000 ha. Studies in various parts of the world, including Portugal, have well-documented a strong and sometimes extreme response in overland flow generation and associated soil losses following wildfire. Over the last two decades, the construction of terraces in preparation of a new eucalypt plantation has become increasingly common in the mountain areas of north-central Portugal, including in recently burnt areas. Terraces are traditionally viewed as a soil conservation technique, however, the present authors have measured high splash and inter-rill erosion on recent terraces and have frequently observed gully formation connecting the terraces over the full hill slope length, as well as within the adjacent unsealed roads. The present study was carried out in a forest catchment in the north-central Portugal that was burnt by a wildfire during the summer of 2010 and logged and then terraced with a bulldozer during the winter 2010. The burnt catchment of roughly 25 ha was instrumented with two subsequent flumes with maximum discharge capacities of 120 and 1700 l sec-1. The bed load that deposited in the smallest flume was removed and weighted in the field at regular intervals during the subsequent three years. The records are being now analyzed, nonetheless preliminary results suggested that, besides the wildfire effects, also post-fire land management played an important role on bedload exports.

  6. Estimation of the marine boundary layer height over the central North Pacific using GPS radio occultation

    Science.gov (United States)

    Winning, Thomas E.; Chen, Yi-Leng; Xie, Feiqin

    2017-01-01

    Global positioning system radio occultation (GPS RO) refractivity data obtained from the first Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) for the years 2007 to 2012 were used to estimate an overall climatology for the height of the marine boundary layer (MBL) over the central North Pacific Ocean including the Hawaiian Island region (10°N-45°N; 125°W-175°W). The trade wind days are identified based on the six-year National Centers for Environmental Prediction (NCEP) global analysis for the same period. About 87% of the RO soundings in summer (June-July-August, JJA) and 47% in winter (December-January-February, DJF) are under trade wind conditions. The MBL height climatology under trade wind conditions is derived and compared to the overall climatology. In general, MBL heights are lowest adjacent to the southern coast of California and gradually increase to the south and west. During the summer (JJA) when the northeasterly trade winds are the dominant surface flow, the median MBL height decreases from 2.0 km over Kauai to 1.9 km over the Big Island with an approximate 2 km maximum that progresses from southwest to northeast throughout the year. If the surface flow is restricted to trade winds only, the maximum MBL heights are located over the same areas, but they increase to a median height of 1.8 km during DJF and 2.1 km during JJA. For the first time, the GPS RO technique allows the depiction of the spatial variations of the MBL height climatology over the central North Pacific.

  7. Seismic hazard map of North and Central America and the Caribbean

    Directory of Open Access Journals (Sweden)

    K. M. Shedlock

    1999-06-01

    Full Text Available Minimization of the loss of life, property damage, and social and economic disruption due to earthquakes depends on reliable estimates of seismic hazard. National, state, and local governments, decision makers, engineers, planners, emergency response organizations, builders, universities, and the general public require seismic hazard estimates for land use planning, improved building design and construction (including adoption of building construction codes, emergency response preparedness plans, economic forecasts, housing and employment decisions, and many more types of risk mitigation. The seismic hazard map of North and Central America and the Caribbean is the concatenation of various national and regional maps, involving a suite of approaches. The combined maps and documentation provide a useful regional seismic hazard framework and serve as a resource for any national or regional agency for further detailed studies applicable to their needs. This seismic hazard map depicts Peak Ground Acceleration (PGA with a 10% chance of exceedance in 50 years. PGA, a short-period ground motion parameter that is proportional to force, is the most commonly mapped ground motion parameter because current building codes that include seismic provisions specify the horizontal force a building should be able to withstand during an earthquake. This seismic hazard map of North and Central America and the Caribbean depicts the likely level of short-period ground motion from earthquakes in a fifty-year window. Short-period ground motions effect short-period structures (e.g., one-to-two story buildings. The highest seismic hazard values in the region generally occur in areas that have been, or are likely to be, the sites of the largest plate boundary earthquakes.

  8. Greenhouse gas fluxes of a shallow lake in south-central North Dakota, USA

    Science.gov (United States)

    Tangen, Brian; Finocchiaro, Raymond; Gleason, Robert A.; Dahl, Charles F.

    2016-01-01

    Greenhouse gas (GHG) fluxes of aquatic ecosystems in the northern Great Plains of the U.S. represent a significant data gap. Consequently, a 3-year study was conducted in south-central North Dakota, USA, to provide an initial estimate of GHG fluxes from a large, shallow lake. Mean GHG fluxes were 0.02 g carbon dioxide (CO2) m−2 h−1, 0.0009 g methane (CH4) m−2 h−1, and 0.0005 mg nitrous oxide (N2O) m−2 h−1. Fluxes of CO2 and CH4 displayed temporal and spatial variability which is characteristic of aquatic ecosystems, while fluxes of N2O were consistently low throughout the study. Comparisons between results of this study and published values suggest that mean daily fluxes of CO2, CH4, and N2O fromLong Lakewere low, particularly when compared to the well-studied prairie pothole wetlands of the region. Similarly, cumulative seasonal CH4 fluxes, which ranged from 2.68–7.58 g CH4 m−2, were relatively low compared to other wetland systems of North America. The observed variability among aquatic ecosystems underscores the need for further research.

  9. Potential field studies of the central San Luis Basin and San Juan Mountains, Colorado and New Mexico, and southern and western Afghanistan

    Science.gov (United States)

    Drenth, Benjamin John

    This dissertation includes three separate chapters, each demonstrating the interpretive utility of potential field (gravity and magnetic) geophysical datasets at various scales and in various geologic environments. The locations of these studies are the central San Luis Basin of Colorado and New Mexico, the San Juan Mountains of southwestern Colorado, and southern and western Afghanistan. The San Luis Basin is the northernmost of the major basins that make up the Rio Grande rift, and interpretation of gravity and aeromagnetic data reveals patterns of rifting, rift-sediment thicknesses, distribution of pre-rift volcanic and sedimentary rocks, and distribution of syn-rift volcanic rocks. Syn-rift Santa Fe Group sediments have a maximum thickness of ˜2 km in the Sanchez graben near the eastern margin of the basin along the central Sangre de Cristo fault zone. Under the Costilla Plains, thickness of these sediments is estimated to reach ˜1.3 km. The Santa Fe Group sediments also reach a thickness of nearly 1 km within the Monte Vista graben near the western basin margin along the San Juan Mountains. A narrow, north-south-trending structural high beneath San Pedro Mesa separates the graben from the structural depression beneath the Costilla Plains. Aeromagnetic anomalies are interpreted to mainly reflect variations of remanent magnetic polarity and burial depth of the 5.3-3.7 Ma Servilleta basalt of the Taos Plateau volcanic field. Magnetic-source depth estimates indicate patterns of subsidence following eruption of the basalt and show that the Sanchez graben has been the site of maximum subsidence. One of the largest and most pronounced gravity lows in North America lies over the rugged San Juan Mountains in southwestern Colorado. A buried, low-density silicic batholith related to an Oligocene volcanic field coincident with the San Juan Mountains has been the accepted interpretation of the source of the gravity low since the 1970s. However, this interpretation was

  10. Palynostratigraphy of the Sanganeh Formation at the East and Central Kopeh-Dagh Basin based on dinoflagellate cysts

    Directory of Open Access Journals (Sweden)

    Narges Shokri

    2015-05-01

    Full Text Available The Sanganeh Formation (Lower Cretaceous has cropped out across the Kopeh-Dagh Basin. The formation conformably overly the Aptian Sarcheshmeh Formation and is in turn overlain conformably by glauconitic sandstone of the Aitamir Formation. The considered formation in eastern and central parts of the basin comprises predominantly dark shale with some interbeds of limestone and siltstone. In order to analyse dinoflagellate content of this rock unit , four stratigraphic sections from east to the center of the basin including Karizak (320m, Mozduran (355m, Sanganeh (550m, and Qarah-Su (580m were measured and sampled palynologically. A total of 370 rock samples taken from the four sections were processed palynologically and scanned under a light microscope. Of these, two sections including Karizak and Mozduran were barren of any preserved dinocysts while, the samples from other two sections (Sanganeh and Qarah-Su yielded a relatively diverse and well preserved assemblage. According to the recognized dinocysts, two zones DZ1 and DZ2 were established in Sanganeh and Qarah-Su sections. The differentiated dinozones were coincident to Odontochitina operculata and Pseudoceratium turneri which are index for late Aptian-early Albian for the Sanganeh Formation at the mentioned stratigraphic sections. In addition, distribution and dispersion of dinoflagellate cyst contents indicate an increasing trend of the depth from east to the central parts of the Kopeh-Dagh Basin.

  11. Digital model of the seabed geomorphology of southern-central Espirito Santo basin and northern Campos basin; Modelo digital da geomorfologia do fundo oceanico do centro-sul da bacia do Espirito Santo e norte da bacia de Campos

    Energy Technology Data Exchange (ETDEWEB)

    Schreiner, Simone; Souza, Mariana Beatriz Ferraz Mendonca de; Migliorelli, Joana Paiva Robalo [Petroleo Brasileiro S. A. (PETROBRAS), Rio de Janeiro, RJ (Brazil). Unidade de Servicos de Exploracao e Producao], Emails: schreiner@petrobras.com.br, mbfms.fototerra@petrobras.com.br, joanamigli.fototerra@petrobras.com.br

    2009-05-15

    That communication brings the result of a bathymetric mosaic of converted in a digital model of the ocean topography, consisting of 17 seismic projects 3D, besides 17 multibeam bathymetry surveys of South-Central Espirito Santo Basin and Northern Campos Basin.

  12. Sedimentology and hydrocarbon habitat of the submarine-fan deposits of the Central Carpathian Paleogene Basin (NE Slovakia)

    Energy Technology Data Exchange (ETDEWEB)

    Sotak, J. [Slovak Academy of Sciences, Banska Bystrica (Slovakia). Geological Institute; Pereszlenyi, M. [VVNP Research Oil Company for Exploration and Production, Bratislava (Slovakia); Marschalko, R.; Starek, D. [Slovak Academy of Sciences, Bratislava (Slovakia). Geological Institute; Milicka, J. [Comenius University, Bratislava (Slovakia). Dept. of Geochemistry

    2001-01-01

    The Central Carpathian Paleogene Basin accommodates a subsiding area of the destructive plate-margin. The basin history comprises marginal faulting and alluvial fan accumulation (E{sub 2}); transgressive onlap by shoreface sediments and carbonate platform deposits (E{sub 2}); glacio-eustatic regression induced by cooling (Terminal Eocene Event); forced regression, tectonic subsidence and growth-fault accumulation of basin-floor and slope fans (E{sub 3}); decelerating subsidence, aggradation and sea-level rising during the mud-rich deposition (O{sub 1}); high-magnitude drop in sea-level (Mid-Oligocene Event), retroarc backstep of depocenters and lowstand accumulation of sand-rich fans and suprafans (O{sub 2}-M{sub 1}); subduction-related shortening and basin inversion along the northern margins affected by backthrusting and transpressional deformation (O{sub 2}-M{sub 1}). The basin-fill sequence has poor (TOC {<=} 0.5%) to fair (TOC < 1.0%) quality of source rocks. Maturity of OM ranges from initial to relic stage of HC generation. Paleogene rock-extracts display a good correlation with scarce trapped oils. 'The presence of solid bitumens and HC-rich fluid inclusions indicates overpressure conditions during HC generation and migration. Potential HC reservoirs can be expected in porous lithologies (scarp breccias), in basement highs and traps related to backthrusting, fault-propagation folding and strike-slip tectonics. (author)

  13. Petrogenesis of the crater-facies Tokapal kimberlite pipe, Indrāvati Basin, Central India

    Directory of Open Access Journals (Sweden)

    N.V. Chalapathi Rao

    2014-11-01

    Full Text Available New geochemical data of the crater-facies Tokapal kimberlite system sandwiched between the lower and upper stratigraphic horizons of the Mesoproterozoic Indrāvati Basin are presented. The kimberlite has been subjected to extensive and pervasive low-temperature alteration. Spinel is the only primary phase identifiable, while olivine macrocrysts and juvenile lapilli are largely pseudomorphed (talc-serpentine-carbonate alteration. However, with the exception of the alkalies, major element oxides display systematic fractionation trends; likewise, HFSE patterns are well correlated and allow petrogenetic interpretation. Various crustal contamination indices such as (SiO2 + Al2O3 + Na2O/(MgO + K2O and Si/Mg are close to those of uncontaminated kimberlites. Similar La/Yb (79–109 of the Tokapal samples with those from the kimberlites of Wajrakarur (73–145 and Narayanpet (72–156, Eastern Dharwar craton, southern India implies a similarity in their genesis. In the discriminant plots involving HFSE the Tokapal samples display strong affinities to Group II kimberlites from southern Africa and central India as well as to ‘transitional kimberlites’ from the Eastern Dharwar craton, southern India, and those from the Prieska and Kuruman provinces of southern Africa. There is a striking similarity in the depleted-mantle (TDM Nd model ages of the Tokapal kimberlite system, Bastar craton, the kimberlites from NKF and WKF, Eastern Dharwar craton, and the Majhgawan diatreme, Bundelkhand craton, with the emplacement age of some of the lamproites from within and around the Palaeo-Mesoproterozoic Cuddapah basin, southern India. These similar ages imply a major tectonomagmatic event, possibly related to the break-up of the supercontinent of Columbia, at 1.3–1.5 Ga across the three cratons. The ‘transitional’ geochemical features displayed by many of the Mesoproterozoic potassic-ultrapotassic rocks, across these Indian cratons are inferred to be

  14. Petrogenesis of the crater-facies Tokapal kimberlite pipe, Indrāvati Basin, Central India

    Institute of Scientific and Technical Information of China (English)

    N.V. Chalapathi Rao; B. Lehmann; B.K. Panwar; Alok Kumar; D. Mainkar

    2014-01-01

    New geochemical data of the crater-facies Tokapal kimberlite system sandwiched between the lower and upper stratigraphic horizons of the Mesoproterozoic Indrāvati Basin are presented. The kimberlite has been subjected to extensive and pervasive low-temperature alteration. Spinel is the only primary phase identifiable, while olivine macrocrysts and juvenile lapilli are largely pseudomorphed (talc-serpentine-carbonate alteration). However, with the exception of the alkalies, major element oxides display systematic fractionation trends; likewise, HFSE patterns are well correlated and allow petrogenetic interpretation. Various crustal contamination indices such as (SiO2 þ Al2O3 þ Na2O)/(MgO þ K2O) and Si/Mg are close to those of uncontaminated kimberlites. Similar La/Yb (79e109) of the Tokapal samples with those from the kimberlites of Wajrakarur (73e145) and Narayanpet (72e156), Eastern Dharwar craton, southern India implies a similarity in their genesis. In the discriminant plots involving HFSE the Tokapal samples display strong affinities to Group II kimberlites from southern Africa and central India as well as to‘transitional kimberlites’ from the Eastern Dharwar craton, southern India, and those from the Prieska and Kuruman provinces of southern Africa. There is a striking similarity in the depleted-mantle (TDM) Nd model ages of the Tokapal kimberlite system, Bastar craton, the kimberlites from NKF and WKF, Eastern Dharwar craton, and the Majhgawan diatreme, Bundelkhand craton, with the emplacement age of some of the lamproites from within and around the Palaeo-Mesoproterozoic Cuddapah basin, southern India. These similar ages imply a major tectonomagmatic event, possibly related to the break-up of the supercontinent of Columbia, at 1.3e1.5 Ga across the three cratons. The ‘transitional’ geochemical features displayed by many of the Mesoproterozoic potassic-ultrapotassic rocks, across these Indian cratons are inferred to be memories of the

  15. Naturalization of central European plants in North America: species traits, habitats, propagule pressure, residence time.

    Science.gov (United States)

    Pyšek, Petr; Manceur, Ameur M; Alba, Christina; McGregor, Kirsty F; Pergl, Jan; Stajerová, Katerina; Chytrý, Milan; Danihelka, Jiří; Kartesz, John; Klimesova, Jitka; Lucanova, Magdalena; Moravcová, Lenka; Nishino, Misako; Sadlo, Jiri; Suda, Jan; Tichy, Lubomir; Kühn, Ingolf

    2015-03-01

    The factors that promote invasive behavior in introduced plant species occur across many scales of biological and ecological organization. Factors that act at relatively small scales, for example, the evolution of biological traits associated with invasiveness, scale up to shape species distributions among different climates and habitats, as well as other characteristics linked to invasion, such as attractiveness for cultivation (and by extension propagule pressure). To identify drivers of invasion it is therefore necessary to disentangle the contribution of multiple factors that are interdependent. To this end, we formulated a conceptual model describing the process of invasion of central European species into North America based on a sequence of "drivers." We then used confirmatory path analysis to test whether the conceptual model is supported by a statistical model inferred from a comprehensive database containing 466 species. The path analysis revealed that naturalization of central European plants in North America, in terms of the number of North American regions invaded, most strongly depends on residence time in the invaded range and the number of habitats occupied by species in their native range. In addition to the confirmatory path analysis, we identified the effects of various biological traits on several important drivers of the conceptualized invasion process. The data supported a model that included indirect effects of biological traits on invasion via their effect on the number of native range habitats occupied and cultivation in the native range. For example, persistent seed banks and longer flowering periods are positively correlated with number of native habitats, while a stress-tolerant life strategy is negatively correlated with native range cultivation. However, the importance of the biological traits is nearly an order of magnitude less than that of the larger scale drivers and highly dependent on the invasion stage (traits were associated

  16. Aminostratigraphy of Middle and Late Pleistocene deposits in The Netherlands and the southern part of the North Sea Basin

    Science.gov (United States)

    Meijer, T.; Cleveringa, P.

    2009-09-01

    A review of all available amino acid racemization D (alloisoleucine)/L (isoleucine) data from the whole shell of four molluscan species from Late and late Middle Pleistocene deposits of the Netherlands is presented. The data allow the distinction of 5 aminostratigraphical units, NAZ (Netherlands Amino Zone) A-E, each representing a temperate stage. The zones are correlated with marine isotope stages 1, 5e, 7, 9, and 11 respectively. Apart from NAZ-D (MIS 9), in all aminozones the marine transgression reached the present-day onshore area of the Netherlands. The transgression during NAZ-C (Oostermeer Interglacial: MIS 7) seems to be at least as widespread as its counterpart during NAZ-B (Eemian: MIS 5e) in the southern bight of the North Sea Basin. The stratigraphic position of the Oostermeer Interglacial is just below deposits of the Drente phase of the Saalian and because of this position the interglacial marine deposits have formerly erroneously considered to be of Holsteinian age. Neede, the 'classic' Dutch Holsteinian site, is dated in NAZ-E (MIS 11), like Noordbergum. Although the validity of these zones has been checked with independent data, some overlap between succeeding zones may occur. The relation between amino acid data from elsewhere in the North Sea Basin and the Netherlands amino zonation is discussed. The deposits at the Holsteinian stratotype Hummelsbüttel in North West Germany are dated in NAZ-D. This interglacial correlates with MIS 9. The Belvédère Interglacial, which is of importance for its archaeology, is in NAZ-D (MIS 9) and therefore of Holsteinian age as well. The lacustroglacial 'pottery clays' in the Noordbergum area are deposits from two glacial stages, which can be correlated with MIS 8 and 10 (the Elsterian). The pottery clay that is considered equivalent to the German 'Lauenburger Ton' correlates with MIS 10.

  17. Landscape Based Modeling of Nonpoint Source Nitrogen Loading in the Neuse River Basin, North Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Garten, C.T.

    2001-01-11

    The objective of this research was to arrive at a quantitative and qualitative assessment of nonpoint sources of potential excess N under different land use/land cover (LULC) categories in the Neuse River Basin on a seasonal time scale. This assessment is being supplied to EPA's Landscape Characterization Branch, National Exposure Research Laboratory, in Research Triangle Park, NC, for inclusion in a hydrologic model to predict seasonal fluxes of N from the terrestrial landscape to surface receiving waters and groundwater in the Neuse River Basin. The analysis was performed in the following five steps: (1) development of a conceptual model to predict potential excess N on land, (2) a literature review to parameterize N fluxes under LULC categories found in the Neuse River Basin, (3) acquisition of high resolution (15-m pixel) LULC data from EPA's Landscape Characterization Branch, National Exposure Research Laboratory, in Research Triangle Park, NC, (4) acquisition of a soil N inventory map for the Neuse River Basin, (5) calculations of potential excess N on a seasonal basis for the entire Neuse River Basin.

  18. Upper Jurassic - Lower Cretaceous turbidite sandstones in the Central Graben, North Sea; with special focus on the Danish Gertrud Graben

    Energy Technology Data Exchange (ETDEWEB)

    Johannessen, P.

    1998-10-01

    Thick Late Jurassic - Early cretaceous turbidite sandstone successions in the Central Graben are uncommon except from the Moray Firth and Viking Graven north of the Central Graben, where several important hydrocarbon producing turbidite sandstone fields are known. The only hydrocarbon producing turbidite reservoir sandstones in the Central Graben is the up to 55 m thick Ribble Sandstone Member located in the British South-west Central Graben, where it is lying above thick shoreface reservoir sandstones of the Fulmar Formation, separated by offshore claystones of the Kimmeridge Clay Formation. The turbidite sandstones of the Ribble Sandstone Member derived from the more proximal thick reservoir sandstones of the Fulmar Formation located near the Mid North Sea High. It has not yet been possible to correlate thick shoreface sandstones of the Norwegian Ula Formation or the Danish Heno Formation to more distal thick turbidite sandstones derived from the shoreface sandstones. (au) 60 fig., 85 refs.

  19. Organic petrology and geochemistry of Eocene Suzak bituminous marl, north-central Afghanistan: Depositional environment and source rock potential

    Science.gov (United States)

    Hackley, Paul C.; Sanfilipo, John

    2016-01-01

    Organic geochemistry and petrology of Eocene Suzak bituminous marl outcrop samples from Madr village in north-central Afghanistan were characterized via an integrated analytical approach to evaluate depositional environment and source rock potential. Multiple proxies suggest the organic-rich (TOC ∼6 wt.%) bituminous marls are ‘immature’ for oil generation (e.g., vitrinite Ro rock sulfur content is ∼2.3 wt.% whereas sulfur content is ∼5.0–5.6 wt.% in whole rock extracts with high polar components, consistent with extraction from S-rich Type IIs organic matter which could generate hydrocarbons at low thermal maturity. Low Fe-sulfide mineral abundance and comparison of Pr/Ph ratios between saturate and whole extracts suggest limited Fe concentration resulted in sulfurization of organic matter during early diagenesis. From these observations, we infer that a Type IIs kerogen in ‘immature’ bituminous marl at Madr could be generating high sulfur viscous oil which is seeping from outcrop. However, oil-seep samples were not collected for correlation studies. Aluminum-normalized trace element concentrations indicate enrichment of redox sensitive trace elements Mo, U and V and suggest anoxic-euxinic conditions during sediment deposition. The bulk of organic matter observed via optical microscopy is strongly fluorescent amorphous bituminite grading to lamalginite, possibly representing microbial mat facies. Short chain n-alkanes peak at C14–C16 (n-C17/n-C29 > 1) indicating organic input from marine algae and/or bacterial biomass, and sterane/hopane ratios are low (0.12–0.14). Monoaromatic steroids are dominated by C28clearly indicating a marine setting. High gammacerane index values (∼0.9) are consistent with anoxia stratification and may indicate intermittent saline-hypersaline conditions. Stable C isotope ratios also suggest a marine depositional scenario for the Suzak samples, consistent with the presence of marine foraminifera including

  20. A Study Of Fluid Pressure Migration Within The North-Central Oklahoma Seismic Gap

    Science.gov (United States)

    Lambert, C.; Keranen, K. M.; Sickbert, T.

    2015-12-01

    The rise in seismicity in Oklahoma since 2008 provides an unusual opportunity to study fluid migration and the interaction of fluids with faults. One unique area in north-central Oklahoma is a current seismic gap between large clusters in northern and central Oklahoma, providing a window into the temporal evolution of local seismicity. The gap in seismicity occurs across the NNE-SSW trending Nemaha uplift, with long faults relatively well-oriented in the regional stress field. Wastewater disposal occurs both within and on either side of the gap, and seismicity approached both sides of the uplift in 2014. To record seismicity and seismic migration through time within the uplift and along the bounding faults on either side, we deployed a ten station array of broadband sensors in April 2015. Our goal is to detect possible seismic signals related to fluid pressure migration and to ultimately increase our understanding of the fault response to perturbations in fluid pressure. Here we present local earthquake locations from the first months of data and initial focal mechanisms. We detect higher numbers of earthquakes happening within the Nemaha uplift than recorded in existing catalogs. The seismicity is typically events. This pattern of seismicity may represent deformation on small faults as the pressure perturbation migrates into the Nemaha uplift from either side and away from wells within the uplift.

  1. Vectors and malaria transmission in deforested, rural communities in north-central Vietnam

    Directory of Open Access Journals (Sweden)

    Do Manh Cuong

    2010-09-01

    Full Text Available Abstract Background Malaria is still prevalent in rural communities of central Vietnam even though, due to deforestation, the primary vector Anopheles dirus is uncommon. In these situations little is known about the secondary vectors which are responsible for maintaining transmission. Basic information on the identification of the species in these rural communities is required so that transmission parameters, such as ecology, behaviour and vectorial status can be assigned to the appropriate species. Methods In two rural villages - Khe Ngang and Hang Chuon - in Truong Xuan Commune, Quang Binh Province, north central Vietnam, a series of longitudinal entomological surveys were conducted during the wet and dry seasons from 2003 - 2007. In these surveys anopheline mosquitoes were collected in human landing catches, paired human and animal bait collections, and from larval surveys. Specimens belonging to species complexes were identified by PCR and sequence analysis, incrimination of vectors was by detection of circumsporozoite protein using an enzyme-linked immunosorbent assay. Results Over 80% of the anopheline fauna was made up of Anopheles sinensis, Anopheles aconitus, Anopheles harrisoni, Anopheles maculatus, Anopheles sawadwongporni, and Anopheles philippinensis. PCR and sequence analysis resolved identification issues in the Funestus Group, Maculatus Group, Hyrcanus Group and Dirus Complex. Most species were zoophilic and while all species could be collected biting humans significantly higher densities were attracted to cattle and buffalo. Anopheles dirus was the most anthropophilic species but was uncommon making up only 1.24% of all anophelines collected. Anopheles sinensis, An. aconitus, An. harrisoni, An. maculatus, An. sawadwongporni, Anopheles peditaeniatus and An. philippinensis were all found positive for circumsporozoite protein. Heterogeneity in oviposition site preference between species enabled vector densities to be high in both

  2. Geohydrology and numerical simulation of ground-water flow in the central Virgin River basin of Iron and Washington Countries, Utah

    Science.gov (United States)

    Heilweil, V.M.; Freethey, G.W.; Wilkowske, C.D.; Stolp, B.J.; Wilberg, D.E.

    2000-01-01

    Because rapid growth of communities in Washington and Iron Counties, Utah, is expected to cause an increase in the future demand for water resources, a hydrologic investigation was done to better understand ground-water resources within the central Virgin River basin. This study focused on two of the principal ground-water reservoirs within the basin: the upper Ash Creek basin ground-water system and the Navajo and Kayenta aquifer system. The ground-water system of the upper Ash Creek drainage basin consists of three aquifers: the uppermost Quaternary basin-fill aquifer, the Tertiary alluvial-fan aquifer, and the Tertiary Pine Valley monzonite aquifer. These aquifers are naturally bounded by the Hurricane Fault and by drainage divides. On the basis of measurements, estimates, and numerical simulations of reasonable values for all inflow and outflow components, total water moving through the upper Ash Creek drainage basin ground-water system is estimated to be about 14,000 acre-feet per year. Recharge to the upper Ash Creek drainage basin ground-water system is mostly from infiltration of precipitation and seepage from ephemeral and perennial streams. The primary source of discharge is assumed to be evapotranspiration; however, subsurface discharge near Ash Creek Reservoir also may be important. The character of two of the hydrologic boundaries of the upper Ash Creek drainage basin ground-water system is speculative. The eastern boundary provided by the Hurricane Fault is assumed to be a no-flow boundary, and a substantial part of the ground-water discharge from the system is assumed to be subsurface outflow beneath Ash Creek Reservoir along the southern boundary. However, these assumptions might be incorrect because alternative numerical simulations that used different boundary conditions also proved to be feasible. The hydrogeologic character of the aquifers is uncertain because of limited data. Difference in well yield indicate that there is considerable

  3. Implications for Fault and Basin Geometry in the Central California Coast Ranges from Preliminary Gravity and Magnetic Data

    Science.gov (United States)

    Langenheim, V. E.; Jachens, R. C.; Graymer, R. W.; Wentworth, C. M.

    2008-12-01

    Preliminary aeromagnetic and newly processed gravity data help define block-bounding faults and deep sedimentary basins in the central California Coast Ranges, ranging from the Hosgri fault east to the San Andreas fault and from Monterey Bay south to Pt. Conception. Interpretation of these data results in an improved framework for seismic hazard and groundwater studies. Aeromagnetic data include a new survey with a flight-line spacing of 800 m at a nominal 300 m above ground and covering 15,000 km2. More than 11,500 gravity measurements, reprocessed with terrain corrections calculated from 30-m DEMs, form a roughly 2-km grid over most of the study area. Combined potential-field data and existing geologic mapping, delineate major fault-bounded blocks in the central California Coast Ranges. Main block-bounding faults from west to east include the San Gregorio- Hosgri, San Luis-Willmar-Santa Maria River-Little Pine, Oceanic-West Huasna, Nacimiento, Rinconada-South Cuyama, San Juan-Chimineas-Morales, and San Andreas faults. Most of these faults have evidence of Quaternary activity. Gravity gradients indicate that the reach of the San Andreas fault bounding the Gabilan Range and the northern extension of the Rinconada fault bounding the Santa Lucia Range dip steeply southwestward and have a reverse component of slip. Magnetic and microseismicity data suggest that the northern reach of the Hosgri fault dips eastward. The potential-field data also delineate several deep sedimentary basins, such as the 3-4 km deep Cuyama basin, the Santa Maria basin, and several basins along and possibly offset by the Rinconada fault. Gravity data show that the main west-northwest-striking faults bounding the Cuyama basin dip away from the basin, indicating compression adjacent to the big bend in the San Andreas fault. Prominent gravity and magnetic highs northeast of the San Andreas fault immediately east of Cuyama Valley suggest that there the San Andreas fault dips southwest. Such dip

  4. The Holocene palaeogeography and relative sea level for two tidal basins of the German North Sea coast

    Science.gov (United States)

    Bungenstock, Friederike; Wartenberg, Wolfram; Mauz, Barbara; Freund, Holger; Frechen, Manfred; Weerts, Henk J. T.; Berner, Heinrich

    2014-05-01

    The response of coasts to global sea-level rise is highly variable. Knowledge of driving coastal parameters alongside the regional sea-level history is therefore indispensable when the response to global sea-level rise is to be assessed. Here, we study the Holocene relative sea-level of the south coast of the North Sea which is controlled by a number of very local parameters, as well as by regional glacio-isostatic adjustments. It is therefore crucial to restrict the data acquisition and evaluation to small coastal sections, ideally to single tidal basins, to minimize the sources of uncertainties (Bungenstock & Weerts 2010, 2012). We present data from two tidal basins, Langeoog and Jade Bay. For Langeoog a database derived from 600 cores, 68 km of Boomer seismic data, 33 radiocarbon ages and 8 OSL dates is available. (Bungenstock & Schäfer 2009, Mauz & Bungenstock 2007). For the Jade bay, the database comprises sedimentary markers, pollen and macro remains derived from 68 cores. The sedentary chronology is based on 54 radiocarbon ages and pollen constraints (Wartenberg & Freund 2011, Wartenberg et al. 2013). For both tidal basins the sedimentological record was interpreted in terms of the local paleogeographical development since about 7000 cal BP and its influence on the local relative sea-level curve. While the trend of the relative sea level is similar for both tidal basins, it shows a different altitude. The timing of the main marine transgression within the Langeoog area takes place ~3000 cal. BP whereas the sedimentological record of the Jade Bay shows two prominent transgressions, one for ~5000 cal. BP and one for ~3000 cal. BP. The Langeoog palaeo-environment is continuously characterised by marine influence. Within the Jade Bay two different palaeo-environments could be identified, documenting that from the West to the centre the landscape development in the Jade Bay was drainage driven feeding the associated fen peat with minerogenic water but being

  5. Tomographic images of subducted oceans matched to the accretionary records of orogens - Case study of North America and relevance to Central Asia

    Science.gov (United States)

    Sigloch, Karin; Mihalynuk, Mitchell G.; Hosseini, Kasra

    2016-04-01

    Accretionary orogens are the surface record of subduction on the 100-million-year timescale; they aggregate buoyant crustal welts that resisted subduction. The other record of subduction is found in the deep subsurface: oceanic lithosphere preserved in the mantle that records ocean basin closure between successive generations of arcs. Seismic tomography maps out these crumpled paleo-oceans down to the core-mantle boundary, where slab accumulates. One such accumulation of enormous scale is under Eastern Asia, recording the assembly of the Central Asian Orogenic Belt (CAOB). Deep CAOB slab has hardly been explored because tomographic image resolution in the lowermost mantle is limited, but this is rapidly improving. We present new images of the CAOB slabs from our P-wave tomography that includes core-diffracted waves as a technical novelty. The previous slab blur sharpens into the type of elongated geometries expected to trace paleo-trench lines. Since the North American Cordillera is younger than the CAOB (mostly 10,000 km long. North America converged on the two microcontinents by westward subduction of two intervening basins (which we name Mezcalera and Angayucham oceans), culminating in diachronous suturing between ~150 Ma and ~50 Ma. Hence geophysical subsurface evidence negates the widely accepted "Andean-style" model of Farallon-beneath-continent subduction since at least 180 Ma, and supports a Jura-Cretaceous paleogeography closer to today's Southwestern Pacific, or to the Paleozoic CAOB. Though advocated since the 1970's by a minority of geologists, this scenario had not gained wide acceptance due to a record obscured by overprinting, margin-parallel translation, and oroclinal bending. The new subsurface evidence provides specific indications where to seek the decisive Mezcalera-Angayucham suture. The suture is evident in a trail of collapsed Jura-Cretaceous basin relics that run the length of the Cordillera. Reference: Sigloch, K., & Mihalynuk, M. G. (2013

  6. Geomorphic analysis of transient landscapes in the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    Science.gov (United States)

    Andreani, L.; Gloaguen, R.

    2016-01-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. We intend to characterize and understand the complex tectonic setting that produced an intricate pattern of landscapes using tectonic geomorphology, as well as available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in a transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low-amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes. Lower reaches adjust to new base-level conditions and are characterized by multiple knickpoints. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos forearc sliver and (2) the compression along the northern tip of the Central American volcanic arc. Although most of the shortening between the Cocos forearc sliver and the North American Plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén Basin.

  7. Geomorphic analysis of transient landscapes from the Sierra Madre de Chiapas and Maya Mountains (northern Central America): implications for the North American-Caribbean-Cocos plate boundary

    Science.gov (United States)

    Andreani, L.; Gloaguen, R.

    2015-09-01

    We use a geomorphic approach in order to unravel the recent evolution of the diffuse triple junction between the North American, Caribbean, and Cocos plates in northern Central America. The complex tectonic setting produced an intricate pattern of landscapes that we try to systemize using remote sensing tectonic geomorphology and available geological and geophysical data. We classify regions with specific relief characteristics and highlight uplifted relict landscapes in northern Central America. We also analyze the drainage network from the Sierra Madre de Chiapas and Maya Mountains in order to extract information about potential vertical displacements. Our results suggest that most of the landscapes of the Sierra Madre de Chiapas and Maya Mountains are in transient stage. Topographic profiles and morphometric maps highlight elevated relict surfaces that are characterized by a low amplitude relief. The river longitudinal profiles display upper reaches witnessing these relict landscapes while lower segments characterized by multiple knickpoints, that adjust to new base-level conditions. These results backed by published GPS and seismotectonic data allow us to refine and extend existing geodynamic models of the triple junction. Relict landscapes are delimited by faults and thus result from a tectonic control. The topography of the Sierra Madre de Chiapas evolved as the result of (1) the inland migration of deformation related to the coupling between the Chiapas Massif and the Cocos fore-arc sliver, and (2) the compression along the northern tip of the Central America Volcanic Arc. Although most of the shortening between the Cocos fore-arc sliver and the North American plate is accommodated within the Sierra de Chiapas and Sierra de los Cuchumatanes, a small part may be still transmitted to the Maya Mountains and the Belize margin through a "rigid" Petén basin.

  8. Thermocline mixing and vertical oxygen fluxes in the stratified central North Sea

    Directory of Open Access Journals (Sweden)

    L. Rovelli

    2015-07-01

    Full Text Available In recent decades, the central North Sea has been experiencing a general trend of decreasing dissolved oxygen (O2 levels during summer. To understand the potential causes driving lower O2, we investigated summertime turbulence and O2 dynamics in the thermocline and bottom boundary layer (BBL. The study focuses on coupling biogeochemical processes with physical transport processes to identify key drivers of the O2 and organic carbon turnover within the BBL. Combining our flux observations with an analytical process-oriented approach, we resolve the key drivers that ultimately determine the BBL O2 levels. We report substantial tidally-driven turbulent O2 fluxes from the thermocline into the otherwise isolated bottom water. This contribution to the local bottom water O2 and carbon budgets has been largely overlooked and might be a central factor maintaining relatively high O2 levels in the bottom water throughout the stratification period. With the current climate warming projections, we propose that higher water temperature and reduced turbulence could favour migrating algal species that could out-compete other species for light and nutrients, and shift the oxygen production zone higher up within the thermocline while maintaining similar organic carbon export to the bottom water. Due to the substantially lower turbulence levels in the central region of the thermocline as compared to the higher turbulence observed at the thermocline-BBL interface, such a shift in the production layer could lead to further isolation of the bottom water and promote the seasonal occurrence of lower O2 concentrations.

  9. Statistical prediction of seasonal discharge in the Naryn basin for water resources planning in Central Asia

    Science.gov (United States)

    Apel, Heiko; Gafurov, Abror; Gerlitz, Lars; Unger-Shayesteh, Katy; Vorogushyn, Sergiy; Merkushkin, Aleksandr; Merz, Bruno

    2016-04-01

    The semi-arid regions of Central Asia crucially depend on the water resources supplied by the mountainous areas of the Tien-Shan and Pamirs. During the summer months the snow and glacier melt water of the rivers originating in the mountains provides the only water resource available for agricultural production but also for water collection in reservoirs for energy production in winter months. Thus a reliable seasonal forecast of the water resources is crucial for a sustainable management and planning of water resources.. In fact, seasonal forecasts are mandatory tasks of national hydro-meteorological services in the region. Thus this study aims at a statistical forecast of the seasonal water availability, whereas the focus is put on the usage of freely available data in order to facilitate an operational use without data access limitations. The study takes the Naryn basin as a test case, at which outlet the Toktogul reservoir stores the discharge of the Naryn River. As most of the water originates form snow and glacier melt, a statistical forecast model should use data sets that can serve as proxy data for the snow masses and snow water equivalent in late spring, which essentially determines the bulk of the seasonal discharge. CRU climate data describing the precipitation and temperature in the basin during winter and spring was used as base information, which was complemented by MODIS snow cover data processed through ModSnow tool, discharge during the spring and also GRACE gravimetry anomalies. For the construction of linear forecast models monthly as well as multi-monthly means over the period January to April were used to predict the seasonal mean discharge of May-September at the station Uchterek. An automatic model selection was performed in multiple steps, whereas the best models were selected according to several performance measures and their robustness in a leave-one-out cross validation. It could be shown that the seasonal discharge can be predicted with

  10. Sources and the flux pattern of dissolved carbon in rivers of the Yenisey basin draining the Central Siberian Plateau

    Science.gov (United States)

    Prokushkin, A. S.; Pokrovsky, O. S.; Shirokova, L. S.; Korets, M. A.; Viers, J.; Prokushkin, S. G.; Amon, R. M. W.; Guggenberger, G.; McDowell, W. H.

    2011-10-01

    Frequent measurements of dissolved organic (DOC) and inorganic (DIC) carbon concentrations in rivers during snowmelt, the entire ice-free season, and winter were made in five large watersheds (15 000-174 000 km2) of the Central Siberian Plateau (Yenisey River basin). These differ in the degree of continuous permafrost coverage, mean annual air temperature, and the proportion of tundra and forest vegetation. With an annual DOC export from the catchment areas of 2.8-4.7 gC m - 2 as compared to an annual DIC export of 1.0-2.8 gC m - 2, DOC was the dominant component of terrigenous C released to rivers. There was strong temporal variation in the discharge of DOC and DIC. Like for other rivers of the pan-arctic and boreal zones, snowmelt dominated annual fluxes, being 55-71% for water runoff, 64-82% for DOC and 37-41% for DIC. Likewise, DOC and DIC exhibited also a strong spatial variation in C fluxes, with both dissolved C species decreasing from south to north. The rivers of the southern part of the plateau had the largest flow-weighted DOC concentrations among those previously reported for Siberian rivers, but the smallest flow-weighted DIC concentrations. In the study area, DOC and DIC fluxes were negatively correlated with the distribution of continuous permafrost and positively correlated with mean annual air temperature. A synthesis of literature data shows similar trends from west to east, with an eastward decrease of dissolved C concentrations and an increased proportion of DOC in the total dissolved C flux. It appears that there are two contemporary limitations for river export of terrigenous C across Siberia: (1) low productivity of ecosystems with respect to potentially mobilizable organic C, slow weathering rates with concomitant small formation of bicarbonate, and/or wildfire disturbance limit the pools of organic and inorganic C that can be mobilized for transport in rivers (source-limited), and (2) mobilization of available pools of C is constrained by

  11. Miocene Bahean stratigraphy in the Longzhong Basin,northern central China and its implications in environmental change

    Institute of Scientific and Technical Information of China (English)

    LI; Jijun; ZHANG; Jun; SONG; Chunhui; ZHAO; Zhijun; ZHANG; Yong; WANG; Xiuxi; ZHANG; Jianming; CUI; Qiaoyu

    2006-01-01

    Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui,Gansu Province,northern central China.Hipparion weihoense,a typical member of late Middle Miocene Bahean stage,was recently excavated at Yaodian along a well-exposed outcrop.Owing to the importance of the Bahean stage in the mammalian evolution and its potential for environmental change,we suggested a name of Yaodian Formation for the stratigraphy,which is correlated to the Bahe Formation at Lantian,Shaanxi.High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 11.67 Ma and 7.43 Ma,with the site bearing Hipparion weihoense being estimated at about 10.54-10.30 Ma,providing first magnetostratigraphic chronology for the Bahean Stage.The Yaodian Formation consists of fluvial channel deposits (11.67-10.40 Ma) at the bottom,floodplain deposits in the middle (10.40-9.23 Ma) and shallow lake sediments at the top (9.23-7.43 Ma).This upward fining sequence suggests that the relief in nearby mountain ranges such as West Qinling to the south and Huajia Ling to the north was greatly reduced after long-term denudation,fluvial transport capacity was low,and finally the drainage system was disintegrated,replaced with broad-shallow lakes in which only fine sediments like mud and marlite were deposited,indicating an old stage of development of a planation surface.A remarkable shift in ecology and climatic environment was found at 7.4-7.7 Ma when paleoclimate changed from early warm humid to late dry as indicated by sedimentary facies changed from early shallow lake sequence to late eolian red clays and a former coniferous-deciduous mixed forest was replaced by grassland,leading to great growth of Hipparion Fauna of Baodean stage in the region.Therefore,it is estimated that the present high relief of Qinling and drainage pattern did not come into being until Late Pliocene in response to intensive

  12. Relationship between chemical composition and magnetic susceptibility in sediment cores from Central Indian Ocean Basin

    Indian Academy of Sciences (India)

    J N Pattan; G Parthiban; V K Banakar; A Tomer; M Kulkarni

    2008-04-01

    Three sediment cores in a north–south transect (3°N to 13°S) from different sediment types of the Central Indian Ocean Basin (CIOB) are studied to understand the possible relationship between magnetic susceptibility () and Al, Fe, Ti and Mn concentrations. The calcareous ooze core exhibit lowest (12.32 × 10-7m3 kg−1), Al (2.84%), Fe (1.63%) and Ti (0.14%), terrigenous clay core with moderate (29.9 × 10-7 m3 kg−1) but highest Al (6.84%), Fe (5.20%) and Ti (0.44%), and siliceous ooze core with highest (38.06 × 10-7 m3 kg−1) but moderate Al (4.49%), Fe (2.80%) and Ti (0.19%) contents. The distribution of and detrital proxy elements (Al, Fe, and Ti) are identical in both calcareous and siliceous ooze. Interestingly, in terrigenous core, the behaviour of is identical to only Ti content but not with Al and Fe suggesting possibility of Al and Fe having a non-detrital source. The occurrence of phillipsite in terrigenous clay is evident by the Al-K scatter plot where trend line intersects K axis at more than 50% of total K suggesting excess K in the form of phillipsite. Therefore, the presence of phillipsite might be responsible for negative correlation between and Al ( = −0.52). In siliceous ooze the strong positive correlations among , Alexc and Feexc suggest the presence of authigenic Fe-rich smectite. High Mn content (0.5%) probably in the form of manganese micronodules is also contributing to in both calcareous and siliceous ooze but not in the terrigenous core where mean Mn content (0.1%) is similar to crustal abundance. Thus, systematically records the terrigenous variation in both the biogenic sediments but in terrigenous clay it indirectly suggests the presence of authigenic minerals.

  13. Long-term agroecosystem research in the central Mississippi river basin: introduction, establishment, and overview.

    Science.gov (United States)

    Sadler, E John; Lerch, Robert N; Kitchen, Newell R; Anderson, Stephen H; Baffaut, Claire; Sudduth, Kenneth A; Prato, Anthony A; Kremer, Robert J; Vories, Earl D; Myers, D Brent; Broz, Robert; Miles, Randall J; Young, Fred J

    2015-01-01

    Many challenges currently facing agriculture require long-term data on landscape-scale hydrologic responses to weather, such as from the Goodwater Creek Experimental Watershed (GCEW), located in northeastern Missouri, USA. This watershed is prone to surface runoff despite shallow slopes, as a result of a significant smectitic clay layer 30 to 50 cm deep that restricts downward flow of water and gives rise to a periodic perched water table. This paper is the first in a series that documents the database developed from GCEW. The objectives of this paper are to (i) establish the context of long-term data and the federal infrastructure that provides it, (ii) describe the GCEW/ Central Mississippi River Basin (CMRB) establishment and the geophysical and anthropogenic context, (iii) summarize in brief the collected research results published using data from within GCEW, (iv) describe the series of papers this work introduces, and (v) identify knowledge gaps and research needs. The rationale for the collection derives from converging trends in data from long-term research, integration of multiple disciplines, and increasing public awareness of increasingly larger problems. The outcome of those trends includes being selected as the CMRB site in the USDA-ARS Long-Term Agro-Ecosystem Research (LTAR) network. Research needs include quantifying watershed scale fluxes of N, P, K, sediment, and energy, accounting for fluxes involving forest, livestock, and anthropogenic sources, scaling from near-term point-scale results to increasingly long and broad scales, and considering whole-system interactions. This special section informs the scientific community about this database and provides support for its future use in research to solve natural resource problems important to US agricultural, environmental, and science policy.

  14. Geothermal energy from deep sedimentary basins: The Valley of Mexico (Central Mexico)

    Science.gov (United States)

    Lenhardt, Nils; Götz, Annette E.

    2015-04-01

    The geothermal potential of the Valley of Mexico has not been addressed in the past, although volcaniclastic settings in other parts of the world contain promising target reservoir formations. A first assessment of the geothermal potential of the Valley of Mexico is based on thermophysical data gained from outcrop analogues, covering all lithofacies types, and evaluation of groundwater temperature and heat flow values from literature. Furthermore, the volumetric approach of Muffler and Cataldi (1978) leads to a first estimation of ca. 4000 TWh (14.4 EJ) of power generation from Neogene volcanic rocks within the Valley of Mexico. Comparison with data from other sedimentary basins where deep geothermal reservoirs are identified shows the high potential of the Valley of Mexico for future geothermal reservoir utilization. The mainly low permeable lithotypes may be operated as stimulated systems, depending on the fracture porosity in the deeper subsurface. In some areas also auto-convective thermal water circulation might be expected and direct heat use without artificial stimulation becomes reasonable. Thermophysical properties of tuffs and siliciclastic rocks qualify them as promising target horizons (Lenhardt and Götz, 2015). The here presented data serve to identify exploration areas and are valuable attributes for reservoir modelling, contributing to (1) a reliable reservoir prognosis, (2) the decision of potential reservoir stimulation, and (3) the planning of long-term efficient reservoir utilization. References Lenhardt, N., Götz, A.E., 2015. Geothermal reservoir potential of volcaniclastic settings: The Valley of Mexico, Central Mexico. Renewable Energy. [in press] Muffler, P., Cataldi, R., 1978. Methods for regional assessment of geothermal resources. Geothermics, 7, 53-89.

  15. Herpetofauna of the cedar glades and associated habitats of the Inner Central Basin of middle Tennessee

    Science.gov (United States)

    Niemiller, M.L.; Graham, Reynolds R.; Glorioso, B.M.; Spiess, J.; Miller, B.T.

    2011-01-01

    The cedar glades and barrens of the Inner Central Basin (ICB) of middle Tennessee support a unique and diverse flora and fauna and represent some of the state's most valued natural areas. We conducted herpetofaunal inventories of the cedar glades, associated barrens, cedar-hardwood forest, and adjacent aquatic habitats of the Stones River drainage of Middle Tennessee, focusing our sampling effort primarily at seven state- or federally owned properties in Rutherford and Wilson counties. These properties included Stones River National Battlefield (SRNB), Flat Rock State Natural Area (FRSNA), Vesta Cedar Glade State Natural Area (VSNA), Fall Creek Recreation Area (FCRA) on J. Percy Priest Wildlife Management Area, Cedars of Lebanon State Forest (CLSF), Cedars of Lebanon State Forest Natural Area (CLSNA), and Cedars of Lebanon State Park (CLSP). We used a variety of inventory techniques in terrestrial, aquatic, and subterranean habitats to survey these properties periodically from 1989 to 2010. We documented 49 species (22 amphibian and 27 reptile) accounting for 75.4% of the 65 herpetofaunal species thought to occur in the ICB, including records for Cemophora coccinea, Aneides aeneus, Gyrinophilus palleucus, Ambystoma barbouri, and Pseudotriton montanus. We found differences in alpha and beta diversity between sites, with the CLSF complex containing a high of 41 herpetofaunal species and FRSNA containing a low of 23 species. Beta diversity comparisons indicated similarity in amphibian species composition between FRSNA and CLSF and between SRNB and CLSF (9 shared species), and in reptile species composition between VSNA and the CLSF complex (16 shared species). We compare the results of our inventory with two previous studies conducted in the area and discuss the relative abundance, conservation, and threats to the herpetofaunal community of these habitats.

  16. Monoterpene Compositions of Three Forested Ecosystems in the Central Amazon Basin

    Science.gov (United States)

    Jardine, A.; Fuentes, J. D.; Manzi, A. O.; Higuchi, N.; Chambers, J. Q.; Jardine, K.

    2014-12-01

    Monoterpenes play fundamental roles as secondary metabolites in forested ecosystems and as gas and liquid phase secondary organic aerosol (SOA) precursors in their surrounding atmospheres. While the chemical pathways involved in ozonolysis driven SOA formation from individual monoterpene precursors is known, local and regional chemical transport models are still lacking observations of speciated monoterpenes from forested atmospheres. Here, we present high vertically resolved mixing ratio profiles of speciated monoterpenes from the ambient air of three neighboring forested ecosystems in the central Amazon Basin. Two well-drained plateau primary forests and one seasonally flooded valley forest were sampled during the afternoon hours (13:00 - 16:30) on walkup towers from the initiation of the 2013-14 wet season through the onset of the 2014 dry season (Nov 2013 - Jul 2014). Ambient mixing ratios in all three ecosystems were greatest in the upper canopy with secondary sources of some monoterpenes within the sub-canopies. Relative vertical compositions of monoterpenes did not change significantly throughout the seasons for either ecosystem type. Both ecosystem types were dominated by d-limonene (up to 1.6 ppb) with equally strong mixing ratios of alpha-pinene in the valley compared to the much weaker a-pinene mixing ratios on the plateaus (up to 200 ppt). The highly reactive cis- and trans-beta-ocimene were consistently present in both ecosystems (up to 250 ppt) with the addition of equally high camphene mixing ratios in the valley forest (up to 200 ppt) which is present in the plateau ecosystems in low quantities (50 ppt). With respect to clean atmosphere mixing ratios of 10 ppb ozone, lifetimes are below 2 hours for camphene and below 30 minutes for ocimene, suggesting a potentially large impact on local and possibly regional ozonolysis and subsequent SOA composition.

  17. A pair of seamount chains in the Central Indian Basin, identified from multibeam mapping

    Digital Repository Service at National Institute of Oceanography (India)

    Kodagali, V.N.

    Indian Basin. The average depth in this basin is around 5,100 m. Height of these features range from 200 to 1700 m, with varying morphologies ranging from pointed cones to flat tops and cratered tops. Two distinct chains of seamounts and abyssal hills...

  18. Glacier contribution to flow in two high-altitude streams of the semi-arid Huasco Basin, northern-central Chile

    Science.gov (United States)

    Gascoin, Simon; Ponce, Rodrigo; Kinnard, Christophe; MacDonell, Shelley

    2010-05-01

    In the semi-arid north-central Chile, populated lowlands rely on runoff and groundwater recharge generated in the high altitude areas of the Andes mountain range. In spite of its importance in terms of water resources, the water balance in these areas is poorly known. In particular, the relative contribution of the cryosphere components (snowpack, glaciers, rock glaciers) to the regional water balance has not been thoroughly evaluated yet. We examine the hydrological importance of glaciers in the case of two well-monitored high-altitude watersheds of the Huasco Basin in northern-central Chile (29°S). We use data from a five years glaciological monitoring program to assess the quantity of water that comes from glaciers fusion per watershed. Then, we compare it with the measured discharge at five stream gauge stations located between 2620 m and 3980 m. The results reveal a substantial contribution of the glaciers to the hydrological balance of the study area. At the regional scale, the water balance is dominated by the snowpack dynamics.

  19. Integrated well log and 2-D seismic data interpretation to image the subsurface stratigraphy and structure in north-eastern Bornu (Chad) basin

    Science.gov (United States)

    Isyaku, Aminu A.; Rust, Derek; Teeuw, Richard; Whitworth, Malcolm

    2016-09-01

    Structural and stratigraphic mapping within the Bornu Basin in north east Nigeria was commonly carried out using traditional field geological methods. However, such traditional approaches remain inadequate in the semi-arid region characterised by topographically flat areas and lack of continuous bedrock outcrops that are mostly concealed beneath sand cover. Previous studies in the north-eastern part of the basin carried out using ditch cuttings from few wells and disconnected seismic data were largely inadequate and the resulting stratigraphic analyses were more often generalised. This paper presents an integrated structural and stratigraphic study of the basin using combined subsurface geophysical datasets. A Combined Log Pattern (CLP) method is a well log analysis, which utilises various well log data including gamma ray, resistivity, bulk density and sonic logs to identify lithology and stratigraphic boundaries of subsurface formations. This method is applied to constrain the subsurface stratigraphy of the north-eastern part of the Bornu Basin bordering the Lake Chad. In addition to qualitative combined well log analysis, the time-depth relationship of the sonic log and seismic data was quantitatively determined by tying a well with an intersecting seismic section to validate the stratigraphic facies horizons identified. Four well log facies and their environments of deposition were characterised from the combined well log analysis of the different log types. It is discovered that the Cretaceous basement structural features controlled the deposition of overlying formations in the basin. Without intact core data, the shallower wells were discovered to have bottomed over subsurface horst features while deeper wells penetrated into the basal facies contained mainly within the grabens. Main subsurface structural lineaments in the area include NW-SE, NE-SW and NNW-SSE trending faults, which mainly formed the horst and graben features. Some stratigraphic formations

  20. Palaeogene hardgrounds and associated intraclast lag deposits as the substrates of ferromanganese crusts and nuclei of nodules: Inferences of abyssal current in the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Gupta, S.M.

    The Palaeogene substrates of ferromanganese crusts and nuclei of nodules collected from the Central Indian Basin chiefly consist of incipient to younger pelagic hard grounds and associated intraclast lag deposits. The clayey lumps, ferromanganese...

  1. HYDROGEOMORPHIC SETTING, CHARACTERISTICS, AND RESPONSE TO STREAM INCISION OF MONTANA RIPARIAN MEADOWS IN THE CENTRAL GREAT BASIN--IMPLICATIONS FOR RESTORATION

    Science.gov (United States)

    Riparian wet meadow complexes in the mountains of the central Great Basin are scarce, ecologically important systems that are threatened by stream incision. An interdisciplinary group has investigated 1) the origin, characteristics, and controls on the evolution of these riparian...

  2. Structure and age of the Lower Magdalena Valley basin basement, northern Colombia: New reflection-seismic and U-Pb-Hf insights into the termination of the central andes against the Caribbean basin

    Science.gov (United States)

    Mora-Bohórquez, J. Alejandro; Ibánez-Mejia, Mauricio; Oncken, Onno; de Freitas, Mario; Vélez, Vickye; Mesa, Andrés; Serna, Lina

    2017-03-01

    Detailed interpretations of reflection seismic data and new U-Pb and Hf isotope geochemistry in zircon, reveal that the basement of the Lower Magdalena Valley basin is the northward continuation of the basement terranes of the northern Central Cordillera, and thus that the Lower Magdalena experienced a similar pre-Cenozoic tectonic history as the latter. New U-Pb and Hf analyses of zircon from borehole basement samples retrieved in the basin show that the southeastern region consists of Permo-Triassic (232-300Ma) metasediments, which were intruded by Late Cretaceous (75-89 Ma) granitoids. In the northern Central Cordillera, west of the Palestina Fault System, similar Permo-Triassic terranes are also intruded by Late Cretaceous felsic plutons and display ESE-WNW-trending structures. Therefore, our new data and analyses prove not only the extension of the Permo-Triassic Tahamí-Panzenú terrane into the western Lower Magdalena, but also the along-strike continuity of the Upper Cretaceous magmatic arc of the northern Central Cordillera, which includes the Antioquia Batholith and related plutons. Hf isotopic analyses from the Upper Cretaceous Bonga pluton suggest that it intruded new crust with oceanic affinity, which we interpret as the northern continuation of a Lower Cretaceous oceanic terrane (Quebradagrande?) into the westernmost Lower Magdalena. Volcanic andesitic basement predominates in the northwestern Lower Magdalena while Cretaceous low-grade metamorphic rocks that correlate with similar terranes in the Sierra Nevada de Santa Marta and Guajira are dominant in the northeast, suggesting that the Tahamí-Panzenú terrane does not extend into the northern Lower Magdalena. Although the northeastern region of the Lower Magdalena has a similar NE-SW fabric as the San Lucas Ridge of the northeastern Central Cordillera and the Sierra Nevada de Santa Marta, lithologic and geochronologic data suggest that the San Lucas terrane terminates to the north against the

  3. Brittle Deformation in the Ordos Basin in response to the Mesozoic destruction of the North China Craton

    Science.gov (United States)

    Wang, Q.; Jiang, L.

    2012-12-01

    Craton is continental block that has been tectonically stable since at least Proterozoic. Some cratons, however, become unstable for some geodynamic reasons. The North China Craton (NCC) is an example. Structure geological, geochemical, and geophysical works have revealed that the NCC was destructed in Cretaceous and that lithosphere thickness beneath the eastern NCC were thinned by 120 km. The present study will focus on deformation of the western NCC, and to understand the effect of the Mesozoic destruction of the North China Craton (NCC). Structural partitioning of the Ordos Basin, which is located in the western NCC, from the eastern NCC occurred during the Mesozoic. Unlike the eastern NCC where many Cretaceous metamorphic core complexes developed, sedimentary cover of the NCC remains nearly horizontal and deformation is manifested by joint. We visited 216 sites of outcrops and got 1928 joints measurements, among which 270 from Jurassic sandstones, 1378 from the Upper Triassic sandstones, 124 from the Middle and Lower Triassic sandstones, and 156 from Paleozoic sandstones. In the interior of the Ordos Basin, joints developed quite well in the Triassic strata, while joints in the Jurassic stata developed weakly and no joint in the Cretaceous strata. The Mesozoic stratigraphic thickness are: 1000 meters for the Lower Triassic, the Middle Triassic sandstone with thickness of 800 meters, 3000 meters for the Upper Triassic, 4000 meters for the Jurassic, and 1100 meters for the Lower Cretaceous. The vertical difference in joint development might be related to the burying depth of the strata: the higher the strata, the smaller the lithostatic stress, and then the weaker the joint. Joints in all stratigraphic levels showed a similar strain direction with the sigma 1 (the maximum pressure stress) vertical and the sigma 3 (the minimum pressure stress) horizontal and running N-S. The unconformity below the Cretaceous further indicates that joints in Jurassic and Triassic

  4. Shallow geothermal investigations into the existence of the Valles Caldera outflow plume near Ponderosa and Jemez Pueblo, north-central, New Mexico

    Science.gov (United States)

    Salaz, Robert Ezekiel

    Geothermal research within the Jemez Mountains spans several decades and is documented in many papers. This study serves to extend the research boundary to the south and east outside of Valles caldera and Canon de San Diego, where the main occurrences of geothermal activity are located. The focus of this investigation is to test for a deep ~900 m, stratigraphically-bound thermal aquifer within the Madera Limestone along the western margin of the Santo Domingo basin transition zone near Ponderosa and Jemez Pueblo, in north-central New Mexico. Numerous springs were sampled for aqueous geochemistry to identify leakage of a deeper geothermal aquifer into shallow aquifers. Wells were sampled for temperature anomalies. In addition, two travertine deposits were analyzed for stable isotope composition and one deposit was dated using U-Series techniques to assess the timing and origin of deposition. This study is important because researchers in other extensional basins have identified reasonably good geothermal reservoirs in deep carbonate aquifers that are similar in geologic setting to the Madera Limestone aquifer of this study. The existence of a deep geothermal aquifer near Ponderosa and Jemez Pueblo, New Mexico could prove to be another prospect for geothermal exploration in the Jemez Mountains. Aqueous geochemistry of springs are plotted on ternary Piper diagrams to help classify similar geochemical trends and group these trends into recognizable patterns. These data indicate calcium carbonate rich waters in the north that may gradationally change to alkaline type waters as they flow south through the study area. Contrasting this data, SiO2 and TDS concentrations show two separate systems that may indicate separate confined aquifers. Two distinct TDS regions are observed, one with higher concentrations (>1000 ppm) shows a decrease from N-S and one with lower concentrations (ProQuest.).

  5. Magnetostratigraphic dating of the Huojiadi Paleolithic site in the Nihewan Basin, North China

    NARCIS (Netherlands)

    Liu, Ping; Deng, Chenglong; Li, Shihu; Zhu, Rixiang

    2010-01-01

    The fluvio-lacustrine sequences in the Nihewan Basin, northern China provide important terrestrial archives of paleoclimate and paleoenvironment as well as an important source of Paleolithic settlements and therefore early human occupation in the eastern Old World. Magnetostratigraphic dating of the

  6. Geological evolution of the North Sea: Cross-border basin modeling study on the schillground high

    NARCIS (Netherlands)

    Heim, S.; Lutz, R.; Nelskamp, S.; Verweij, J.M.; Kaufmann, D.; Reinhardt, L.

    2013-01-01

    This study presents the results of a basin modeling study covering the cross-border area of the southern Schillground High in the Dutch-German offshore area. A high resolution petroleum system model has been constructed with the aim to evaluate the hydrocarbon generation potential of Carboniferous s

  7. Nutrient mass balance for the Albemarle-Pamlico Drainage Basin, North Carolina and Virginia, 1990

    Science.gov (United States)

    McMahon, G.; Woodside, M.D.

    1997-01-01

    A 1990 nitrogen and phosphorus mass balance calculated for eight National Stream Quality Accounting Network (NASQAN) basins in the Albemarle-Pamlico Drainage Basin indicated the importance of agricultural nonpoint sources of nitrogen and phosphorus and watershed nitrogen retention and processing capabilities. Basin total nitrogen and phosphorus input estimates were calculated for atmospheric deposition (which averaged 27 percent of total nitrogen inputs and 22 percent of total phosphorus inputs); crop fertilizer (27 and 25 percent); animal-waste (22 and 50 percent, respectively); point sources (3 percent each of total nitrogen and total phosphorus inputs); and biological nitrogen fixation (21 percent of total nitrogen inputs). Highest in-stream nitrogen and phosphorus loads were measured in predominantly agricultural drainage areas. Intermediate loads were observed in mixed agricultural/urban drainage areas; the lowest loads were measured in mixed agricultural/forested drainage areas. The difference between the sum of the nutrient input categories and the sum of the instream nutrient loads and crop-harvest nutrient removal was assigned to a residual category for the basin. The residual category averaged 51 percent of total nitrogen inputs and 54 percent of total phosphorus inputs.

  8. Source rocks and related petroleum systems of the Chelif Basin, (western Tellian domain, north Algeria)

    NARCIS (Netherlands)

    Arab, Mohamed; Bracène, Rabah; Roure, François; Zazoun, Réda Samy; Mahdjoub, Yamina; Badji, Rabie

    2015-01-01

    In the Chelif basin, the geochemical characterization reveals that the Upper Cretaceous and Messinian shales have a high generation potential. The former exhibits fair to good TOC values ranging from 0.5 to 1.2% with a max. of 7%. The Messinian series show TOC values comprised between 0.5 and 2.3% a

  9. The issues of the self-fill aquifer in the north Bohemian brown coal basin

    Energy Technology Data Exchange (ETDEWEB)

    Halir, J.; Zizka, L. [Brown Coal Research Inst., Most (Czech Republic)

    2010-07-01

    The brown coal basin in the Czech Republic is located in the northwestern region of the country. Mining activities in the region have led to the flooding of various underground areas. This paper described the dewatering activities conducted as a safety procedure in a mine located in the brown coal basin. Pumping stations were established in various parts of the basin to collect inflows. Average annual pumping for the stations is approximately 990,000 m{sup 3} of mine water. The deepest pumping station in the basin is 90 meters under sea level. The activities are being conducted to ensure that a self-fill system is established to create a large self-filling water horizon after mining activities have stopped. Depressions in the mine will be successively flooded to create reservoirs of self-filling water. A computerized model of the water fluctuation rates in the mine is being prepare to accurately characterize the filling process. 6 refs., 2 figs.

  10. Impact of Sustainable Agriculture on Secondary School Agricultural Education Teachers and Programs in the North Central Region.

    Science.gov (United States)

    Agbaje, Kehinde Aderemi Ajaiyeoba; Martin, Robert A.; Williams, David L.

    2001-01-01

    Responses from 298 of 600 secondary agriculture teachers in north central United States revealed limited impact of sustainable agriculture. Most teachers had neutral perceptions; a moderate number taught it, but not from a systems perspective. However, related agronomy topics were taught, providing a possible foundation for future inclusion of…

  11. "El Miedo y El Hambre": Understanding the Familial, Social, and Educational Realities of Undocumented Latino Families in North Central Indiana

    Science.gov (United States)

    Viramontez Anguiano, Ruben P.; Lopez, Anayeli

    2012-01-01

    This study explored how different ecological factors, within and outside the family, affected the educational success of the children of undocumented families. The sample consisted of 63 immigrant Latino parents (40 families) who resided in North Central Indiana. This study utilized an ethnographic research design. Findings demonstrated that…

  12. 78 FR 50441 - Iowa Wetland Management District, 35 Counties in North-Central and Northwest Iowa; Environmental...

    Science.gov (United States)

    2013-08-19

    ... comprehensive conservation plan (CCP) for the Iowa Wetland Management District (district, WMD) for public review... sound principles of fish and wildlife management, conservation, legal mandates, and Service policies. In... Fish and Wildlife Service Iowa Wetland Management District, 35 Counties in North-Central and...

  13. Working Together to Make a Difference in Rural America: North Central Regional Center for Rural Development, 2010 Annual Report

    Science.gov (United States)

    North Central Regional Center for Rural Development, 2011

    2011-01-01

    The North Central Regional Center for Rural Development (NCRCRD) is one of four regional centers in the United States that have worked to improve the quality of life in rural communities for nearly 40 years. With funding from the USDA National Institute of Food and Agriculture and the land-grant universities in our 12-state region, the NCRCRD…

  14. Spring distribution and density of minke whale Balaenoptera acutorostrata along an offshore bank in the central North Sea

    NARCIS (Netherlands)

    Boer, de M.N.

    2010-01-01

    Minke whales were recorded in the central North Sea in an area characterised by frontal features and high productivity northeast of the Dogger Bank (4677 km2). Survey efforts were carried out from 28 March to 2 July 2007, at a finer scale than in earlier studies in the region, using 2 vessels as pla

  15. Anopheline (Diptera:Culicidae) breeding in a traditional tank-based village ecosystem in north central Sri Lanka

    DEFF Research Database (Denmark)

    Amerasinghe, F P; Konradsen, F; Fonseka, K T;

    1997-01-01

    A 13-mo survey of immature anopheline mosquitoes breeding in surface water habitats was done at Mahameegaswewa village within the Huruluwewa watershed in north central Sri Lanka as part of a multidisciplinary study on malaria epidemiology. The watershed is representative of the ancient small tank...

  16. Re-Engineering Vocational and Technical Education (VTE) for Sustainable Development in North Central Geo-Political Zone, Nigeria

    Science.gov (United States)

    Sofoluwe, Abayomi Olumade

    2013-01-01

    The purpose of the study is to re-engineer vocational and technical education for sustainable development in the North Central Geo-Political Zone in Nigeria. The research design adopted was a survey inferential type. Stratified random was used to select 36 schools out of 98 schools while 920 students out of 3680 students were sampled. The data…

  17. Application of ICT (Information and Communication Technology) in the Management of Universities in the North-Central State of Nigeria

    Science.gov (United States)

    Oboegbulem, Angie Ijeoma; Godwin, Ochai

    2013-01-01

    This study investigated the application of ICT (information and communication technology) in the management of universities in the north-central Nigeria. The study was a descriptive survey. The population of the study comprised 1,294 respondents in federal and state universities (763 in federal and 531 in state universities). The sample size…

  18. Estimating regional pore pressure distribution using 3D seismic velocities in the Dutch Central North Sea Graben

    NARCIS (Netherlands)

    Winthaegen, P.L.A.; Verweij, J.M.

    2003-01-01

    The application of the empirical Eaton method to calibrated sonic well information and 3D seismic interval velocity data in the southeastern part of the Central North Sea Graben, using the Japsen (Glob. Planet. Change 24 (2000) 189) normal velocitydepth trend, resulted in the identification of an un

  19. The Baltic Klint beneath the central Baltic Sea and its comparison with the North Estonian Klint

    Science.gov (United States)

    Tuuling, Igor; Flodén, Tom

    2016-06-01

    Along its contact with the Baltic Shield, the margin of the East European Platform reveals a well-developed, flooded terraced relief. The most striking and consistent set of escarpments at the contact of the Lower Palaeozoic calcareous and terrigenous rocks, known as the Baltic Klint (BK), extends from northwest of Russia to the Swedish island of Öland. Marine seismic reflection profiling in 1990-2004 revealed the central Baltic Sea Klint (BSK) section in detail and enabled comparison of its geology/geomorphology with a classical klint-section onshore, namely the North Estonian Klint (NEK). The conception of the BK onshore, which is based on the land-sea separating terraced relief in northern Estonia, is not fully applicable beneath the sea. Therefore, we consider that the BSK includes the entire terraced Cambrian outcrop. We suggest the term "Baltic Klint Complex" to include the well-terraced margin of the Ordovician limestone outcrop, which is weakly developed in Estonia. Because of a steady lithological framework of the bedrock layers across the southern slope of the Fennoscandian Shield, the central BSK in the western and the NEK in the eastern part of the Baltic Homocline have largely identical morphologies. The North Estonian Ordovician limestone plateau with the calcareous crest of the BK extends across the central Baltic Sea, whereas morphological changes/variations along the Klint base occur due to the east-westerly lithostratigraphic/thickness changes in the siliciclastic Cambrian sequence. The verge of the NEK, located some 30-50 m above sea level, starts to drop in altitude as its east-westerly course turns to northeast-southwest in western Estonia. Further westwards, the BK shifts gradually into southerly deepening (0.1-0.2°) layers as its crest drops to c. 150 m below sea level (b.s.l.) near Gotska Sandön. This course change is accompanied by a considerable decrease in thickness of the platform sedimentary cover, as below the central Baltic Sea the

  20. Reconstructing multiple arc-basin systems in the Altai-Junggar area (NW China): Implications for the architecture and evolution of the western Central Asian Orogenic Belt

    Science.gov (United States)

    Li, Di; He, Dengfa; Tang, Yong

    2016-05-01

    The Altai-Junggar area in northwestern China is a critical region to gain insights on the tectonic framework and geological evolution of the western Central Asian Orogenic Belt (CAOB). In this study, we report results from integrated geological, geochemical and geophysical investigations on the Wulungu Depression of the Junggar Basin to determine the basement nature of the basin and understand its amalgamation history with the Chinese Altai, within the broad tectonic evolution of the Altai-Junggar area. Based on borehole and seismic data, the Wulungu Depression is subdivided into two NW-trending tectonic units (Suosuoquan Sag and Hongyan High) by southward-vergent thrust faults. The Suosuoquan Sag consists of the Middle-Late Devonian basaltic andesite, andesite, dacite, tuff, tuffaceous sandstone and tuffite, and the overlying Early Carboniferous volcano-sedimentary sequence with lava flows and shallow marine sediments from a proximal juvenile provenance (zircon εHf(t) = 6.0-14.9), compared to the Late Carboniferous andesite and rhyolite in the Hongyan High. Zircon SIMS U-Pb ages for dacites and andesites indicate that these volcanics in the Suosuoquan Sag and Hongyan High erupted at 376.3 Ma and 313.4 Ma, respectively. The Middle-Late Devonian basaltic andesites from well LC1 are calc-alkaline and exhibit primitive magma-like MgO contents (7.9-8.6%) and Mg# values (66-68), with low initial 87Sr/86Sr (0.703269-0.704808) and positive εNd(t) values (6.6-7.6), and relatively high Zr abundance (98.2-116.0 ppm) and Zr/Y ratios (5.1-5.4), enrichment in LREEs and LILEs (e.g., Th and U) and depletion in Nb, Ta and Ti, suggesting that they were probably derived from a metasomatized depleted mantle in a retro-arc extensional setting. The well LC1 andesitic tuffs, well L8 dacites, well WL1 dacitic tuffs and well L5 andesites belong to calc-alkaline and metaluminous to peraluminous (A/CNK = 0.8-1.7) series, and display low Mg# values (35-46) and variably positive εNd(t) (4

  1. Structure and isostatic compensation of the Comorin Ridge, north central Indian Ocean

    Science.gov (United States)

    Sreejith, K. M.; Krishna, K. S.; Bansal, A. R.

    2008-11-01

    Bathymetry, gravity and magnetic data (about 9200 lkm) of the Comorin Ridge, north central Indian Ocean were investigated using the transfer function and forward model techniques to understand the mode of isostatic compensation and origin of the ridge. The ridge extends for about 500 km in NNW-SSE direction and associates with low-amplitude gravity anomalies ranging from 25 to 30 mGal compared to the ridge relief, suggesting that the anomalies are compensated at deeper depths. From Admittance analysis an Airy model or local compensation with an elastic plate thickness (Te) of about 3 km and crust thickness (t) of 15-20 km are suggested for the southern part of the Comorin Ridge (south of 5°N), whereas for the northern part a flexural plate model with an elastic thickness of about 15 km is obtained. Admittance analysis together with the results from gravity forward modelling reveal that the south part was emplaced on relatively weak oceanic crust with both surface and subsurface loading, while the north part was emplaced on the continental crust. Based on present studies and published plate kinematic models we interpret that the Comorin Ridge was evolved at about 90 Ma during the rift stage of Madagascar from the southwest of India. We have also demarcated the continent-ocean boundary (COB) west of Sri Lanka and southern tip of India, which runs across the strike of the ridge, placing the northern part of the ridge on continent and southern part on oceanic crust. On the southern part of the ridge eastern flank is steep-faulted up to 0.6 km and is controlled by the 79°E FZ and then by COB.

  2. Oxygen and Hydrogen Isotopes of Waters in the Ordos Basin,China: Implications for Recharge of Groundwater in the North of Cretaceous Groundwater Basin

    Institute of Scientific and Technical Information of China (English)

    YANG Yuncheng; SHEN Zhaoli; WENG Dongguang; HOU Guangcai; ZHAO Zhenhong; WANG Dong; PANG Zhonghe

    2009-01-01

    Hundreds of precipitation samples collected from meteorological stations in the Ordos Basin from January 1988 to December 2005 were used to set up a local meteoric water line and to calculate weighted average isotopic compositions of modern precipitation.Oxygen and hydrogen isotopes, with and gradually decrease in summer and fall,illustrating that the seasonal effect is considerable.They also show that the isotopic difference between south portion and north portion of the Ordos Basin are not obvious.and the isotope in the middle portion iS normally depleted.The isotope compositions of 32 samples collected from shallow groundwater(less than a depth of 150 m)in desert plateau range from for JD.Most of them are identical with modern precipitation.The isotope compositions of 22 middle and deep groundwaters(greater than a depth of 275 m)fall in ranges from-11.6‰to-8.8‰with an average of-10.2‰ for £18O and from-89‰ to-63‰ with an average of-76‰ for £D.The average values are significantly less than those of modern precipitation,illustrating that the middle and deep groundwaters were recharged at comparatively lower air temperatures.Primary analysis of 14C shows that the recharge of the middle and deep groundwaters started at late Pleistocene.The isotopes of 13 lake water samples collected from eight lakes define a local evaporation trend,with a relatively flat slope of 3.77,and show that the lake waters were mainly fed by modern precipitation and shallow groundwater.

  3. Exhumation of the Panama basement complex and basins: Implications for the closure of the Central American seaway

    Science.gov (United States)

    Ramírez, Diego A.; Foster, David A.; Min, Kyoungwon; Montes, Camilo; Cardona, Agustín.; Sadove, Gephen

    2016-05-01

    The emergence of the Central American isthmus occurred episodically from Eocene to Pliocene time and was caused by a series of tectonic and volcanic processes. Results from zircon U-Pb geochronology, zircon (U-Th)/He (ZHe) and apatite (U-Th)/He (AHe) thermochronology, and zircon Lu-Hf isotopic data from sedimentary (sandstones and recent river sands) and plutonic rocks from the Azuero Peninsula and Central Panama document the exhumation and uplift history of the Panamanian basement complex. Our data support previous paleobotanical and thermochronological studies that suggest that by middle Eocene time some areas of Central Panama and Azuero Peninsula were exposed above sea level as a series of islands surrounded by shallow open marine waters. The Gatuncillo, Cobachón and Tonosí formations were deposited during this partial emergence. Transtension in the Oligocene-early Miocene produced various pull-apart basins (e.g., the Canal Basin) and local uplift that exhumed the Eocene strata (Gatuncillo and Cobachón formations). This event probably reduced circulation between the Pacific Ocean and the Caribbean Sea. The Tonosí Formation records late Miocene to Pleistocene cooling and exhumation, which may be related to uplift above the subducting Coiba Ridge. These results suggest that the emergence of the Isthmus of Panama followed a series of diachronous events that led to the final closure of the Central American seaway.

  4. Marine vertebrates from the Santonian coastal carbonates of northwestern Germany - a tool for the reconstruction of a Proto- North Sea Basin intertidal dinosaur-exchange bridge

    Science.gov (United States)

    Diedrich, Cajus G.; Scheer, Udo

    2015-09-01

    A diverse vertebrate fauna, dominated by shark teeth, is recorded from conglomerates within the limestones of the Upper Cretaceous (Santonian) Burgsteinfurt Formation of northwestern Germany. The conglomerate beds comprise carbonatic, glauconitic and phosphate nodules, as well as Triassic, Jurassic and Cretaceous extraclasts. The Burgsteinfurt Formation conglomerates contain fining-upwards parasequences 2-20 cm in thickness, interpreted as tempestite layers within a unit formed by larger-scale Milankovitch Cycles. The presence of the inoceramid Sphenoceramus patootensis and belemnite Gonioteuthis granulata indicate a late Santonian age for the unit. The studied vertebrate fauna from the Weiner Esch locality consists of 20 selachian species (14 macroselachians and 6 microselachians), a few teleosts, rare marine mosasaur remains, and one tooth from a theropod dinosaur. 95% of the vertebrates in the assemblage are depositionally autochthonous, with the remaining material reworked from older underlying Cenomanian-Coniacian (lower Upper Cretaceous) limestones. On the basis of observed sedimentary structures, the scarcity of deep-sea selachians, and the dominance of the Mitsukurinidae (59% of the preserved shark fauna) in the fossil assemblage, the unit is interpreted as a shallow (0-3 metres deep), subtidal, nearshore environment, or even subaerial carbonate-sand islands, located on the southern margin of a submarine swell. The presence of a Santonian theropod in this deposit, and other dinosaur records in northern Germany, together support the interpretation of a short-lived uplift event with strong upwelling influence for the Northwestphalian-Lippe submarine swell north of the Rhenish Massif in the southern Proto- North Sea Basin. A new migration model for dinosaurs moving along carbonate coasts or intertidal zones of shallow carbonate-sand islands in Central Europe is presented, which may explain the scattered distribution of dinosaur remains across Europe in the

  5. Petroleum geological investigations in East greenland: project `Resources of the sedimentary basins of North and East Greenland`

    Energy Technology Data Exchange (ETDEWEB)

    Stemmerik, L.; Clausen, O.R.; Larsen, M.; Piasecki, S.; Therkelsen, J. [Geological Survey of Denmark and Greenland, Copenhagen (Denmark); Korstgaard, J. [Univ. of Aarhus, Geological Inst., Aarhus (Denmark); Seidler, L.; Surlyk, F. [Univ. of Copenhagen, Geological Inst., Copenhagen (Denmark)

    1997-12-31

    The multidisciplinary research project `Resources of the sedimentary basins of North and East Greenland` was initiated in 1995. The 1996 field work in East Greenland concentrated on integrated structural, sedimentological and biostratigraphical studies of the Upper Permian and Mesozoic successions. The most important new results arising from the 1996 field work are: 1) Re-interpretation of the Upper Permian Schuchert Dal Formation as a low stand turbidite unit within the Ravnefjeld Formation; 2) Recognition of Middle Jurassic deposits and thick lowermost Cretaceous sandstones on Hold with Hope; 3) Interpretation of a full spectrum of scarp-derived coarse-clastic mass movement deposits inter-bedded with Cretaceous shales on eastern Traill Oe; 4) The presence of a thick sand-rich Cretaceous turbidite succession on eastern Traill Oe; 5) Re-interpretation of the Mesozoic-Cenozoic fault systems on Traill Oe and Geographical Society Oe. (EG) 24 refs.

  6. Provenance of the Lower Triassic Bunter Sandstone Formation: implications for distribution and architecture of aeolian vs. fluvial reservoirs in the North German Basin

    DEFF Research Database (Denmark)

    Olivarius, Mette; Weibel, Rikke; Friis, Henrik

    2017-01-01

    Zircon U–Pb geochronometry, heavy mineral analyses and conventional seismic reflection data were used to interpret the provenance of the Lower Triassic Bunter Sandstone Formation. The succession was sampled in five Danish wells in the northern part of the North German Basin. The results show that s...

  7. Revised Upper Cenozoic stratigraphy of the Dutch sector of the North Sea Basin: towards an integrated lithostratigraphic, seismostratigraphic and allostratigraphic approach

    NARCIS (Netherlands)

    Rijsdijk, K.F.; Passchier, S.; Weerts, H.J.T.; Laban, C.; Leeuwen, R.J.W. van; Ebbing, J.H.J.

    2005-01-01

    A revised Upper Cenozoic stratigraphic framework of the Dutch sector of the North Sea Basin is presented whereby offshore stratigraphic units are integrated or correlated with onshore units. The framework is based on an integrated stratigraphic approach that combines elements of lithostratigraphy, s

  8. Revised Upper Cenozoic stratigraphy of the Dutch sector of the North Sea Basin: Towards an integrated lithostratigraphic, seismostratigraphic and allostratigraphic approach

    NARCIS (Netherlands)

    Rijsdijk, K.F.; Passchier, S.; Weerts, H.J.T.; Laban, C.; Leeuwen, R.J.W. van; Ebbing, J.H.J.

    2005-01-01

    A revised Upper Cenozoic stratigraphic framework of the Dutch sector of the North Sea Basin is presented whereby offshore stratigraphic units are integrated or correlated with onshore units. The framework is based on an integrated stratigraphic approach that combines elements of lithostratigraphy, s

  9. Late Pleistocene evolution of the Rhine-Meuse system in the southern North Sea basin: imprints of climate change, sea-level oscillation and glacio-isostacy

    NARCIS (Netherlands)

    Busschers, F.S.; Kasse, C.; Balen, R.T. van; Berghe, J. van den; Cohen, K.M.; Weerts, H.J.T.; Wallinga, J.; Johns, C.; Cleveringa, P.; Bunnik, F.P.M.

    2007-01-01

    High-resolution continuous core material, geophysical measurements, and hundreds of archived core descriptions enabled to identify 13 Late Pleistocene Rhine-Meuse sedimentary units in the infill of the southern part of the North Sea basin (the Netherlands, northwestern Europe). This sediment record

  10. Late Pleistocene evolution of the Rhine in the southern North-Sea Basin: imprints of climate change, sea-level oscillations and glacio-isostacy

    NARCIS (Netherlands)

    Busschers, F.S.; Kasse, C.; van Balen, R.T.; Vandenberghe, J.; Cohen, K.M.; Weerts, H.J.T.; Wallinga, J.

    2007-01-01

    High-resolution continuous core material, geophysical measurements, and hundreds of archived core descriptions enabled to identify 13 Late Pleistocene Rhine-Meuse sedimentary units in the infill of the southern part of the North Sea basin (the Netherlands, northwestern Europe). This sediment record

  11. Organic matter provenance, palaeoproductivity and bottom water anoxia during the Cenomanian/Turonian oceanic anoxic event in the Newfoundland Basin (northern proto North Atlantic Ocean)

    NARCIS (Netherlands)

    van Bentum, E.C.; Reichart, G.J.; Sinninghe Damsté, J.S.

    2012-01-01

    Free and sulfur-bound biomarkers in sediments deposited in the northern proto North Atlantic (Newfoundland Basin, ODP Site 1276) during the Cenomanian-Turonian oceanic anoxic event 2 (OAE-2) were studied. The delta C-13 records of phytane and lycopane confirmed the stratigraphic position of the posi

  12. Organic matter provenance, palaeoproductivity and bottom water anoxia during the Cenomanian/Turonian oceanic anoxic event in the Newfoundland Basin (northern proto North Atlantic Ocean)

    NARCIS (Netherlands)

    Bentum, E.C. van; Reichart, G.-J.; Sinninghe Damsté, J.S.

    2012-01-01

    Free and sulfur-bound biomarkers in sediments deposited in the northern proto North Atlantic (Newfoundland Basin, ODP Site 1276) during the Cenomanian-Turonian oceanic anoxic event 2 (OAE-2) were studied. The δ 13C records of phytane and lycopane confirmed the stratigraphic position of the positive

  13. Fluvial evolution of the Rhine during the last interglacial-glacial cycle in the southern North Sea basin: A review and look forward

    NARCIS (Netherlands)

    Peeters, J.; Busschers, F.S.; Stouthamer, E.

    2015-01-01

    This paper presents the current state of knowledge on the evolution and depositional history of the River Rhine in the southern part of the North Sea basin during the upper Middle and Late Pleistocene, and its response to climate change, sea-level oscillation and glacio-isostasy. The study focuses o

  14. Hydrogeology and hydrogeochemistry at a site of strategic importance: the Pareja Limno-reservoir drainage basin (Guadalajara, central Spain)

    Science.gov (United States)

    Molina-Navarro, Eugenio; Sastre-Merlín, Antonio; Vicente, Rosa; Martínez-Pérez, Silvia

    2014-08-01

    A small calcareous basin in central Spain was studied to establish the role of groundwater in the Pareja Limno-reservoir. Limno-reservoirs aim to preserve a constant water level in the riverine zone of large reservoirs to mitigate the impacts arising from their construction. Groundwater flow contribution (mean 60 %) was derived by recharge estimation. In situ measurements (spring discharge, electrical conductivity and sulfate) were undertaken and spring discharge was compared with a drought index. Twenty-eight springs were monitored and three hydrogeological units (HGUs) were defined: a carbonate plateau (HGU1), the underlying aquitard (HGU2), and the gypsum-enriched HGU3. HGU1 is the main aquifer and may play a role in the preservation of the limno-reservoir water level. Hydrogeochemical sampling was conducted and the code PHREEQC used to describe the main geochemical processes. Weathering and dissolution of calcite and gypsum seem to control the hydrogeochemical processes in the basin. Water progresses from Ca2+-HCO3 - in the upper basin to Ca2+-SO4 2- in the lower basin, where HGU3 outcrops. A clear temporal pattern was observed in the limno-reservoir, with salinity decreasing in winter and increasing in summer. This variation was wider at the river outlet, but the mixing of the river discharge with limno-reservoir water buffered it.

  15. Paleomagnetic and Anisotropy of Magnetic Susceptibility (AMS analyses of the Plio-Pleistocene extensional Todi basin, Central Italy

    Directory of Open Access Journals (Sweden)

    L. Alfonsi

    1997-06-01

    Full Text Available In the last few years paleomagnetic investigations within the Apennine chain have revealed that the area is characterized by a complex pattern of deformation, not linkable to a simple and homogeneous process. In order to estimate the amount, sense and timing of vertical axis rotations within the Central Apennines, Neogene continental basins have been investigated for paleomagnetic studies. The paleomagnetic results obtained in the Plio-Pleistocene Todi basin showed that the Upper Pliocene-Lower Pleistocene evolution, associated with major dip-slip tectonics, has not involved vertical axis rotation since that time. The Anisotropy of Magnetic Susceptibility analysis (AMS, carried out on the same samples treated for paleomagnetic determination, revealed the presence of two groups of specimens characterized by different magnetic lineation directions. One direction trends NE-SW and is parallel to the orientation of the regional extension stress typical of the area. This direction is observed throughout the northern basin. The other, restricted to the southern basin, trends N-S and shows no links with the tectonic, hydrological-sedimentary conditions of the area. The results of the AMS analysis will be presented and discussed in the light of the rock magnetic results and the tectonic framework of the area.

  16. Water-level data for the Albuquerque Basin and adjacent areas, central New Mexico, period of record through September 30, 2014

    Science.gov (United States)

    Beman, Joseph E.

    2015-10-21

    The Albuquerque Basin, located in central New Mexico, is about 100 miles long and 25–40 miles wide. The basin is hydrologically defined as the extent of consolidated and unconsolidated deposits of Tertiary and Quaternary age that encompasses the structural Rio Grande Rift. Drinking-water supplies throughout the basin were obtained solely from groundwater resources until December 2008, when treatment and distribution of surface water from the Rio Grande through the San Juan-Chama Drinking Water Project began. A 20-percent population increase in the basin from 1990 to 2000 and a 22-percent population increase from 2000 to 2010 resulted in an increased demand for water.

  17. ESR dating of the Majuangou and Banshan Paleolithic sites in the Nihewan Basin, North China.

    Science.gov (United States)

    Liu, Chun-Ru; Yin, Gong-Ming; Deng, Cheng-Long; Han, Fei; Song, Wei-Juan

    2014-08-01

    The fluvio-lacustrine sequences in the Nihewan Basin, northern China provide an important source of Paleolithic settlements and therefore early human occupation in the eastern Old World. Here we present electron spin resonance (ESR) chronology for the Majuangou (MJG-III, MJG-II and MJG-I) and Banshan (BS) Paleolithic sites in this basin by the quartz Ti-Li center ESR dating. Results show that the ages of MJG-III and MJG-II could be estimated to be ∼1.70 Ma (millions of years ago); of MJG-I, ∼1.40 Ma; and BS, ∼1.35 Ma. This ESR chronology is consistent with the previous magnetochronology, thus providing strong support for the earliest human presence at the high northern latitudes of Northeast Asia.

  18. Groundwater flowing the forefield of the CSA mine (North Bohemian Brown Coal Basin in the Czech Republic)

    Energy Technology Data Exchange (ETDEWEB)

    Zizka, L.; Halir, J. [Brown Coal Research Inst., Most (Czech Republic)

    2010-07-01

    The North Bohemian Brown Coal Basin is home to one of the largest active open cast mines in the Czech Republic. Groundwater flow in the quaternary sediments is causing stability problems in the upper overburden at the mine. A 3-D geological model was used to simulate groundwater flow in the area. The lithological characteristics and hydrogeological conditions of the mine were also considered in order to identify areas that may pose risks during the extraction of mineral resources. The simulation focused on the characterization of the quaternary and crystalline aquifer collectors located in the region of the mine. The study showed that groundwater flow is influenced by the configuration of the quaternary floor, as well as by the deposition and character of the basin sediments and crystalline rocks. The donation area corresponds with the mountain slopes. Groundwater flow is influenced by disruptions in the crystalline roof with quaternary sediments. The quaternary aquifer will be dewatered in order to ensure the future safety of the mine. 3 refs., 2 figs.

  19. Hydro engineering Feasibility Study of Surface Runoff Water Harvesting in Al-Ajeej Basin, North West Iraq

    Directory of Open Access Journals (Sweden)

    Thair M. Al-Taiee

    2013-04-01

    Full Text Available The hydro engineering  characteristics of Al-Ajeej basin which was located within south Sinjar plain north west Iraq was analyzed to predict the possibility of surface runoff harvesting during rainfall season in the upstream sites in this basin using watershed modeling system (WMS. The hydrological feasibility of constructing small dam on Al-Ajeej valley with some preliminary design calculations were presented. The best optimum dam site was selected to be located (3.95 km downstream the confluence of Al-Badee branch with Al-Ajeej valley (35° 46¢ 6² Latitude and Longitude 41° 36¢ 11² having a catchment's area of (3043km2. The proposed dam  height was (12.5 meter with a dam length of (1277m, while the normal storage volume of the reservoir is (38.8 million m3. Construction a dams in such sites characterized by water shortage during all  around the year will give an aid in the sustainable development of such area by increasing  the cultivation lands, the agricultural products and also modify the income of the villagers living  in this area leading to prevent them leaving their lands to other places

  20. A regional ocean circulation model for the mid-Cretaceous North Atlantic Basin: implications for black shale formation

    Directory of Open Access Journals (Sweden)

    R. P. M. Topper

    2011-03-01

    Full Text Available High concentrations of organic matter accumulated in marine sediments during Oceanic Anoxic Events (OAEs in the Cretaceous. Model studies examining these events invariably make use of global ocean circulation models. In this study, a regional model for the North Atlantic Basin during OAE2 at the Cenomanian-Turonian boundary has been developed. A first order check of the results has been performed by comparison with the results of a recent global Cenomanian CCSM3 run, from which boundary and initial conditions were obtained. The regional model is able to maintain tracer patterns and to produce velocity patterns similar to the global model. The sensitivity of the basin tracer and circulation patterns to changes in the geometry of the connections with the global ocean is examined with three experiments with different bathymetries near the sponges. Different geometries turn out to have little effect on tracer distribution, but do affect circulation and upwelling patterns. The regional model is also used to test the hypothesis that ocean circulation may have been behind the deposition of black shales during OAEs. Three scenarios are tested which are thought to represent pre-OAE, OAE and post-OAE situations. Model results confirm that Pacific intermediate inflow together with coastal upwelling could have enhanced primary production during OAE2. A low sea level in the pre-OAE scenario could have inhibited large scale black shale formation, as could have the opening of the Equatorial Atlantic Seaway in the post-OAE scenario.

  1. Drought Analysis of Haihe Basin in North China based on the Community Land Model, 1960-2010

    Science.gov (United States)

    Qin, Y.; Yang, D.; Lei, H.

    2014-12-01

    Drought severity not only depends on weather anomaly, but is also related to terrestrial hydrological condition to a large extent. In this study, we analyzed droughts using indices based on precipitation and soil moisture during the period of 1960-2010 in Haihe basin, which is a typical drought-prone region in North China. The Soil Moisture Drought Severity (SMDS) and Standardized Precipitation Index (SPI) are used to evaluate drought severity. SMDS is calculated based on the monthly soil moisture of upper 50cm from the simulation by Community Land Model (CLM 4.0) and SPI is calculated based on gridded precipitation at 0.05° resolution (5 km × 5 km approximately), which is spatially interpolated from observations. During the last 51 years, 36 severe drought events (affecting areas greater than 20,000 km2 and durations longer than 3 months) have been identified based on SMDS, and 41 drought events identified based on SPI. Results derived from SMDS indicate that there is a significant increasing trend in the drought affected area, and that the drought event occurred in 1999 has the largest affected area. Compared with the drought events derived from SMDS, the events derived from SPI have shorter durations but larger affected areas on average. Although the mean NDVI of the whole basin has been increasing since the 1980s, the two declining periods of 1992-1994 and 1999-2003 show fairly good agreement with the drought events identified in the same periods. Comparison between SMDS and SPI shows the superiority of SMDS for drought assessment in the perspective of terrestrial ecosystem. Keywords: Drought analysis; Standardized Precipitation Index (SPI); Soil Moisture Drought Severity (SMDS); Community Land Model; Haihe basin

  2. Shallow ground-water quality beneath cropland in the Red River of the North Basin, Minnesota and North Dakota, 1993-95

    Science.gov (United States)

    Cowdery, Timothy K.

    1997-01-01

    During 1993-95, the agriculture on two sandy, surficial aquifers in the Red River of the North Basin affected the quality of shallow ground water in each aquifer differently. The Sheyenne Delta aquifer, in the western part of the basin, had land-use, hydrogeological, and rainfall characteristics that allowed few agricultural chemicals to reach or remain in the shallow ground water. The Otter Tail outwash aquifer, in the eastern part of the basin, had characteristics that caused significant amounts of nutrients and pesticides to reach and remain in the shallow ground water. Shallow ground water from both aquifers is dominated by calcium, magnesium, and bicarbonate ions. During the respective sampling periods, water from the Sheyenne Delta aquifer was mostly anoxic and water from the Otter Tail outwash aquifer had a median dissolved oxygen concentration of 3.6 mg/L (milligrams per liter). The median nitrate concentration was 0.03 mg/L as nitrogen (mg/L-N) in shallow ground water from the Sheyenne Delta aquifer and 6.1 mg/L-N in that from the Otter Tail outwash aquifer. Of 18 herbicides and 4 insecticides commonly used in the aquifer areas and for which analyses were done, 5 herbicides and 1 herbicide metabolite were detected in the shallow ground water from the Sheyenne Delta aquifer and 8 herbicides and 2 metabolites were detected in that from the Otter Tail outwash aquifer. The total herbicide concentration median was less than the detection limit in shallow ground water from the Sheyenne Delta aquifer and 0.023 μg/L (micorgrams per liter) in that from the Otter Tail outwash aquifer. Triazine herbicides were the most commonly detected herbicides and were detected at the highest concentrations in the shallow ground water from both study areas. One sample from the Sheyenne Delta aquifer contained a high concentration of picloram. Agricultural chemicals in both aquifers were stratified vertically and their concentration correlated inversely with ground-water age. The

  3. Mountain Meadows Dacite: Oligocene intrusive complex that welds together the Los Angeles Basin, northwestern Peninsular Ranges, and central Transverse Ranges, California

    Science.gov (United States)

    McCulloh, Thane H.; Beyer, Larry A.; Morin, Ronald W.

    2001-01-01

    southwest of the San Andreas Fault Zone is proposed. Our reconstruction incorporates 20° of clockwise rotation of tracts north of the Raymond Fault from the easternmost Santa Monica Mountains to the Vasquez Creek Fault (San Gabriel south branch). We interpret the Vasquez Creek Fault as a reverse and right-lateral tear fault. Right slip on the tear becomes reverse dip slip on the northeast-striking Clamshell-Sawpit fault complex, interpreted as an offset part of the Mount Lukens Fault. This explains the absence of evidence for lateral offset of the Glendora Volcanics and associated younger marine strata where those are broken farther east by the eastern Sierra Madre reverse fault system. About 34 km of right slip is suggested for all breaks of the San Gabriel fault system. New paleogeographic maps of the Paleogene basin margin and of a Middle Miocene marine embayment and strandline derive in part from our palinspastic reconstruction. These appealingly simple maps fit well with data from the central Los Angeles Basin to the south and southwest.

  4. Airborne pollen and fungal spores in Garki, Abuja (North-Central Nigeria).

    Science.gov (United States)

    Ezike, Dimphna Nneka; Nnamani, Catherine V; Ogundipe, Oluwatoyin T; Adekanmbi, Olushola H

    2016-01-01

    The ambient atmosphere is dominated with pollen and spores, which trigger allergic reactions and diseases and impact negatively on human health. A survey of pollen and fungal spores constituents of the atmosphere of Garki, Abuja (North-Central Nigeria) was carried out for 1 year (June 1, 2011-May 31, 2012). The aim of the study was to determine the prevalence and abundance of pollen and fungal spores in the atmosphere and their relationship with meteorological parameters. Airborne samples were trapped using modified Tauber-like pollen trap, and the recipient solutions were subjected to acetolysis. Results revealed the abundance of fungal spores, pollen, fern spores, algal cysts and diatoms in decreasing order of dominance. The atmosphere was qualitatively and quantitatively dominated by pollen during the period of late rainy/harmattan season than the rainy season. Numerous fungal spores were trapped throughout the sampling periods among which Alternaria spp., Fusarium spp., Cladosporium spp. and Curvularia spp. dominated. These fungi have been implicated in allergic diseases and are dermatophytic, causing diverse skin diseases. Other pathogenic fungi found in the studied aeroflora were Dreschlera spp., Helminthosporium spp., Torula spp., Pithomyces spp., Tetraploa spp., Nigrospora ssp., Spadicoides spp., Puccinia spp. and Erysiphe graminis. Total pollen and fungal spores counts do not show significant correlation with meteorological parameters.

  5. Sociodemographic Correlates of Choice of Health Care Services in Six Rural Communities in North Central Nigeria

    Directory of Open Access Journals (Sweden)

    Onyemocho Audu

    2014-01-01

    Full Text Available Household expenditure on health has increasingly remained a major source of health care financing in Nigeria despite the introduction of several social health scheme policies provided by the government for meeting the health care costs of patients. Recognizing these limitations, this study assessed the type of health care services people commonly use in various illnesses and the sociodemographic correlates of the preferred health care services by household heads in six rural communities of North Central Nigeria. A cross-sectional community-based descriptive study design was used to study 154 household heads in the settlements using a multistage sampling method. Multiple logistic regressions were performed to investigate independent predictors that had significant chi-square at P<0.05. The leading causes of illness experienced by respondents were medical conditions (42.0% and 41.7% of them sought treatment from patent medicine vendors. The dominant reasons for health-seeking preferences were financial access (53.7% and proximity (48.6%. Age had a higher impact (Beta = 0.892 on the health-seeking preferences of the respondents as compared to their occupation and religion (Beta = 0.368 and −0.746, resp.. Therefore, in order to meet the health care of patients, it is pertinent that the unmet needs of patients are properly addressed by appropriate agencies.

  6. Hydrology and geochemistry of thermal ground water in southwestern Idaho and north-central Nevada<