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Sample records for junggar basin northwest

  1. Geochemistry of oils from the Junggar basin, northwest China

    USGS Publications Warehouse

    Clayton, J.L.; Yang, J.; King, J.D.; Lillis, P.G.; Warden, A.

    1997-01-01

    The Junggar basin of northwestern China is a structural basin containing a thick sequence of Paleozoic-Pleistocene rocks with estimated oil reserves of as much as 5 billion bbl. Analyses of 19 oil samples from nine producing fields and two oil-stained cores in the Junggar basin revealed the presence of at least five genetic oil types. The geochemistry of the oils indicates source organic matter deposited in fresh to brackish lake and marine environments, including coaly organic matter sources. The volumetrically most important oil type discovered to date is produced from Late Carboniferous-Middle Triassic reservoirs in the giant Karamay field and nearby fields located along the northwestern margin of the Junggar basin. Oil produced from the Mahu field, located downdip in a depression east of the Karamay field, is from a different source than Karamay oils. Unique oil types are also produced from an upper Permian reservoir at Jimusar field in the southeastern part of the basin, and from Tertiary (Oligocene) rocks at Dushanzi field and Lower Jurassic rocks at Qigu field, both located along the southern margin of the basin. Previous studies have demonstrated the presence of Upper Permian source rocks, and the possibility of Mesozoic or Tertiary sources has been proposed, but not tested by geochemical analysis, although analyses of some possible Jurassic coal source rocks have been reported. Our findings indicate that several effective source rocks are present in the basin, including local sources of Mesozoic or younger age for oil accumulations along the southern and southeastern margins of the basin. Future exploration or assessment of petroleum potential of the basin can be improved by considering the geological relationships among oil types, possible oil source rocks, and reservoirs.

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Mesozoic tectonically driven climatic partitioning of the south Junggar and north Tarim basins, northwest China

    SciTech Connect

    Hendrix, M.S.; Graham, S.A.; Brassell, S.C. )

    1991-03-01

    Detailed basin analysis of Mesozoic strata exposed in the south Junggar and north Tarim foreland basin Mesozoic depocenters, northwest China, has documented periodic structural reactivation of the intervening Tian Shan during that era. Coarse alluvial pulses, contained in an otherwise relatively fine-grained section of fluvial lacustrine sediments, were shed off both the north and south flanks of the Tian Shan during the Late Triassic, Latest Jurassic, and late Cretaceous. The lofty modern Tian Shan and associated rain shadow cast over the Tarim basin to the south reflect deformation associated with the early Cenozoic Himalayan collision; so too were the two basins climatically partitioned during the Mesozoic in response to relief produced by orogenesis. During prolonged episodes of relative tectonic quiescence, it appears that Tian Shan relief was too low to confine moisture to the windward side of the range. Most notable is the Middle Jurassic section that is dominated in both basins by a relatively fine-grained series of organic-rich, meandering fluvial, and lacustrine sediments. Pyrolytic analyses of organic-rich mudstones associated with these sediments document high H.I. kerogens, suggesting algal-dominated organic matter typical of anoxic lacustrine settings. However, detailed GC-MS biomarker analysis of the alipaphatic fraction also suggests substantial input from higher land plants in addition to algal sources. Not only are n-alkane distributions typically dominated by high molecular weight compounds with an odd-over-even preference typical of higher land plants, but the abundance of specific diterpenoid biomarker compounds strongly suggests the development of widespread coniferous forests on either side of the range during the Middle Jurassic.

  4. Petroleum source rocks of the Junggar, Tarim, and Turpan basins, northwest China

    SciTech Connect

    Graham, S.A.; Brassell, S.; Carroll, A.R.; McKnight, C.L.; Chu, J.; Hendrix, M.S. ); Xiao, X. ); Demaison, G. ); Liang, Y. )

    1990-05-01

    The sedimentary basins of Xinjiang Uygur Autonomous Region, China, are poorly explored for petroleum. Volumetric adequacy of petroleum source rocks is a critical exploration risk in these basins, particularly because source rock data are limited. However, recent studies provide new source rock data and permit speculative assessment of source rock potential of Xinjiang basins. The Junggar basin, best explored of Xinjiang basins and containing a giant oil field, is underlain over much of its extent by an Upper Permian lacustrine oil-shale sequence that is known for its organic richness and oil source quality. Depending on position in the basin, the Permian section ranges from immature to overmature and is inferred to be the principal source of oil in the basin. Upper Triassic-Middle Jurassic coal measures, including lacustrine rocks, constitute a secondary source rock sequence in the Junggar basin. The smaller intermontane Turpan basin contains a very similar Upper Triassic-Middle Jurassic sequence, which, where sufficiently deeply buried, probably comprises the only significant oil source sequence in the basin. The vast Tarim basin offers the greatest potential variety of petroleum source rocks of all Xinjiang basins, but remains the least well documented. From limited, but geologically planned and focused sampling, Cambrian, Carboniferous, and Permian strata are considered unlikely to be major oil source contributors in the dominantly shallow-marine Paleozoic section of the northern Tarim basin. Only Ordovician black shales appear to have significant oil source potential, and a lower Paleozoic source is confirmed for some Tarim oils by gas chromatography-mass spectrometry analysis. The Upper Triassic-Middle Jurassic sequence of northern Tarim basin, similar to that of the Junggar and Turpan basins in comprising a section rich in coal and lacustrine shale, constitutes another, potentially significant oil source.

  5. Sedimentary record and climatic implications of recurrent deformation in the Tian Shan: Evidence from Mesozoic strata of the north Tarim, south Junggar, and Turpan basins, northwest China

    SciTech Connect

    Hendrix, M.S.; Graham, S.A.; Sobel, E.R.

    1992-01-01

    Detailed stratigraphic, sedimentologic, paleocurrent, and subsidence analyses were conducted on Mesozoic nonmarine sedimentary sections of the south Junggar, north Tarim, and Turpan basins, Xinjang Uygur Autonomous Region, northwest China. These three basins have been foreland basins throughout the Mesozoic and Cenozoic eras, as demonstrated by asymmetrically distributed basinwide sediment accumulations, foreland-style subsidence profiles, and a variety of outcrop and subsurface facies data. Mesozoic paleocurrent indicators measured in the south Junggar and north Tarim basins, as well as Mesozoic sandstone compositions from both basins, indicate that the intervening Tian Shan has existed as a positive physiographic feature partitioning the two basins throughout Mesozoic and Cenozoic time. Paleocurrent, facies, and subsurface isopach data suggest that the Turpan basin was established as a discrete feature by the Early Jurassic period. The timing and style of depositional systems within the north Tarim Mesozoic depocenter, the south Junggar Mesozoic depocenter, and the central Turpan basin are remarkably similar. Upper Triassic strata of each basin consist of alluvial conglomerate and associated braided-fluvial sandstone and siltstone which fine upward into lower through Middle Jurassic, locally organic-rich, meandering-fluvial, and lacustrine strata. Upper Jurassic braided-fluvial red beds in each basin are overlain by a distinct pulse of uppermost Jurassic alluvial conglomerate. Lower Cretaceous exposures consist of fine-grained red beds in north Tarim and Turpan and interbedded red and gray shale with local silty carbonates in south Junggar. Upper Cretaceous strata of the north Tarim and south Junggar basins are composed of alluvial conglomerate with associated braided-fluvial sandstone and siltstone. 94 refs., 17 figs.

  6. Paleo-environment from isotopes and hydrochemistry of groundwater in East Junggar Basin, Northwest China

    NASA Astrophysics Data System (ADS)

    Li, Jie; Pang, Zhonghe; Froehlich, Klaus; Huang, Tianming; Kong, Yanlong; Song, Wenhui; Yun, Hongxiang

    2015-10-01

    Isotopic and geochemical evidence of paleoclimatic conditions from the Pleistocene (∼30ka BP) has been obtained from groundwater in a non-monsoon area in the East Junggar Basin, NW China. The major ion chemistry of groundwater is controlled by some processes including ion exchange in clay minerals and dissolution of gypsum as well as other evaporites in the desert groundwater, while carbonate minerals seem to be essentially absent in the aquifers. The water chemistry, oxygen and deuterium, deuterium excess, and stable carbon isotopes of groundwater show distinctive excursions inferred to be related to environmental variations such as air temperature and land cover change. Shallow groundwater bears an isotopic signature similar to that of the mean annual rainfall in Urumqi, suggesting recharge under warm climate conditions in the Holocene. Deep groundwater in the central part of the basin is characterized by depleted heavy isotopes, lower deuterium excess and low 14C content, indicating lower air temperature in the late Pleistocene, after correction for altitude effect. Old groundwater with enriched 13C indicates the higher proportion of C4 species in the late Pleistocene.

  7. Structural geology and tectonic significance of foreland thrust belts, Tarim and Junggar basins, northwest China

    SciTech Connect

    McKnight, C.L.; Chu, J.; Corroll, A.R.; Hendrix, M.S.; Wang, X.; Graham, S.A.; Liang, Y.H.; Wang, Z.X.; Xiao, X.

    1989-03-01

    The Kalpin uplift, located on the northwestern margin of the Tarim basin is characterized by a series of thin, southeast-vergent thrust plates modified by strike-slip faults. Each thrust plate repeats a sedimentary sequence consisting of upper Proterozoic through Permian shallow marine to nonmarine carbonates and clastics. Tertiary rocks as young as Neogene are affected by the deformation. The most basinward thrust sheet abuts the Bachu uplift, an older structural feature trending almost perpendicular to the thrusts. Sedimentary rocks as old as late Proterozoic are exposed in the Bachu uplift, which apparently represents a west-vergent Late Silurian to Early Devonian thrust belt. An unconformable Silurian-Devonian contact, the presence of Devonian red beds, and another unconformable contact separating Devonian from Upper Carboniferous strata support the interpretation of a middle Paleozoic deformational event. Another unconformity, at the Carboniferous-Permian boundary, apparently coincides with the time of collision of the Tarim craton with the southern margin of central Asia. The Shihezi fold trend, located in the southern Junggar basin, consists of three lines of surface anticlines trending parallel to the axis of the Urumqi foredeep. A thick sequence of Mesozoic and Cenozoic nonmarine sedimentary rocks accumulated in the growing foredeep. Mesozoic and Paleogene strata are deformed in the southern foldbelt, with Jurassic rocks forming the cores of these thrusted anticlines. The Qigu oil field is located in this southern belt. Deformed Neogene and Quaternary strata are exposed in the thrusted anticlines of the middle and northern foldbelts. The Dushanzi oil field is located in the northern belt. The episodic development of compressional structures in northwestern China documents the accretion of a number of tectonic units to the growing southern margin of central Asia through time.

  8. Chemical speciation of redox sensitive elements during hydrocarbon leaching in the Junggar Basin, Northwest China

    NASA Astrophysics Data System (ADS)

    Zheng, Guodong; Fu, Bihong; Takahashi, Yoshio; Kuno, Akihito; Matsuo, Motoyuki; Zhang, Jindong

    2010-11-01

    Bleaching related to seepage of petroleum fluids and subsurface migration of crude oil and natural gas can alter the chemical and mineralogical properties of rocks, while concurrently depleting hydrocarbon reservoirs. Mud volcanoes constitute one type of petroleum seepage present in several areas on the southern margin of the Junggar Basin in the Xinjiang Uygur Autonomous Region, NW China. The results of XRD, XRF, XANES, and Mössbauer spectroscopy on rock samples collected from areas affected by these mud volcanoes revealed an enrichment of certain minerals and elements, as well changes in mineralogical, molecular, or ionic carrier ("species"). After bleaching, reddish sedimentary rocks showed depletion in silica and enrichment of calcium, magnesium, manganese, and iron. Other elements, including aluminum, potassium, sodium, and titanium, were largely unchanged. Reduced iron and sulfur compounds predominated in the bleached rocks, producing changes in color from the original reddish into green, deep gray, and black. Iron and calcium were associated with carbonates, indicating carbonation of these elements during the bleaching processes. Manganese also appeared to be associated with carbonate, though not with sulfate even though sulfate was present in the bleached rocks. Alkaline conditions were apparently the dominant because reduced manganese would have been absent under acidic condition. The alteration of certain minerals, clay minerals in particular, was also observed in bleached rocks, the alteration of smectite-group minerals to chlorite and muscovite, for example. Mineralogical and geochemical changes in rocks bleached by hydrocarbon fluids could provide a better overall understanding of bleaching processes, and may have applications in surface geochemical exploitation and remote imaging.

  9. Cation exchange capacity (Qv) estimation in shaly sand reservoirs: case studies in the Junggar Basin, northwest China

    NASA Astrophysics Data System (ADS)

    Wang, Liang; Mao, Zhi-Qiang; Sun, Zhong-Chun; Luo, Xing-Ping; Deng, Ren-Shuang; Zhang, Ya-Hui; Ren, Bing

    2015-10-01

    Cation exchange capacity (Qv) is a key parameter in resistivity-based water saturation models of shaly sand reservoirs, and the accuracy of Qv calculation is crucial to the prediction of saturations of oil and gas. In this study, a theoretical expression of Qv in terms of shaly sand permeability (Kshaly-sand), total porosity (ϕt), and salinity of formation water (S) is deduced based on the capillary tube model and the physics volume model. Meanwhile, the classical Schlumberger-Doll research (SDR) model has been introduced to estimate Kshaly-sand. On this basis, a novel technique to estimate Qv from nuclear magnetic resonance (NMR) logs is proposed, and the corresponding model is also established, whose model parameters are calibrated by laboratory Qv and NMR measurements of 15 core samples from the Toutunhe formation of the Junggar Basin, northwest China. Based on the experimental data sets, this technique can be extended to reservoir conditions to estimate continuous Qv along the intervals. The processing results of field examples illustrate that the Qv calculated from field NMR logs are consistent with the analyzed results, with the absolute errors within the scope of  ±0.1 mmol cm-3 for the majority of core samples.

  10. Sedimentology, organic geochemistry, and petroleum potential of Jurassic coal measures: Tarim, Junggar, and Turpan Basins, Northwest China

    SciTech Connect

    Hendrix, M.S.; Brassell, S.C.; Carroll, A.R.

    1995-07-01

    Lower and Middle Jurassic coal-bearing strata occur widely throughout central Asia and are well developed in northwestern China, where their thicknesses in the southern Junggar, northern Tarim, and Turpan basins exceed 2500, 2300, and 1500 m, respectively. Examination of these strata along 13 transacts across basin margin outcrop belts indicates that they are entirely nonmarine meandering fluvial deposits with local development of braided fluvial and lacustrine deltaic facies. Chinese subsurface data suggest that regional Jurassic lacustrine facies are present down depositional dip, consistent with predictions from global circulation modeling of Early and Middle Jurassic monsoonal precipitation. Laboratory analyses of coals and organic-rich shales show a dominance of terrestrial, higher plant components. Visual kerogen analysis indicates that vitrinite, inertinite, and exinite are the dominant macerals, and elemental analysis characterizes most kerogens as type III. Rock-Eval analyses yield moderate hydrogen index values (50-300) and very low oxygen index values (<20). Jurassic source rock extracts are characterized by odd-over-even normal alkane distributions, high pristane/phytane and high hopane/sterane ratios, dominance of C{sub 29} sterane homologs, local abundance of diterpenoid compounds, and low abundance of tricyclic terpanes. Geochemical correlation with four petroleums from the Junggar, Tarim, and Turpan basins strongly suggests that the Jurassic coaly deposits and their lacustrine equivalents downdip are petroleum source rocks. Pyrolysis-gas chromatography of selected Jurassic samples suggests that they possess potential for liquid hydrocarbon generation. Expulsion of C{sub 15+}, hydrocarbons from Jurassic source rocks appears likely, despite the traditional view that bituminous coals are incapable of expelling long-chain hydrocarbons.

  11. Genesis analysis of high-gamma ray sandstone reservoir and its log evaluation techniques: a case study from the Junggar basin, northwest China.

    PubMed

    Wang, Liang; Mao, Zhiqiang; Sun, Zhongchun; Luo, Xingping; Song, Yong; Liu, Zhen

    2013-01-01

    In the Junggar basin, northwest China, many high gamma-ray (GR) sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs' recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation's high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR) logs is proposed and proved to be useful in reservoir recognition and physical property evaluation.

  12. Genesis Analysis of High-Gamma Ray Sandstone Reservoir and Its Log Evaluation Techniques: A Case Study from the Junggar Basin, Northwest China

    PubMed Central

    Wang, Liang; Mao, Zhiqiang; Sun, Zhongchun; Luo, Xingping; Song, Yong; Liu, Zhen

    2013-01-01

    In the Junggar basin, northwest China, many high gamma-ray (GR) sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs' recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation's high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR) logs is proposed and proved to be useful in reservoir recognition and physical property evaluation. PMID:24078797

  13. Diagenesis and secondary porosity enhancement from dissolution of analcime cement in reservoir sandstones: The Upper Permian Pingdiquan Formation, Junggar basin, northwest China

    SciTech Connect

    Zhaohui, T.; Longstaffe, F.J. ); Parnell, J. )

    1996-01-01

    The Junggar Basin is one of the largest and most important oil-producing basins in China, in which Upper Permian lacustrine oil shales are among the thickest and richest petroleum source rocks in the world. The Upper Permian Pingdiquan Formation was deposited predominantly in fan-delta sequences within a lacustrine setting. The Pingdiquan Formation sandstones constitute the principal oil reservoirs, whereas the interbedded black shales are the predominant oil source rocks. The early diagenetic mineral assemblage in the sandstones comprises siderite, pyrite, analcime, albite, calcite and authigenic quartz as well as trace amount of halite; By contrast, the late diagenetic minerals are characterized by authigenic K-feldspar, ankerite, and minor amounts of mixed-layer clay minerals. Petrographic, mineralogical and available paleoecological data suggest that early authigenic minerals in the sandstones were controlled by alternating periodic fresh water and saline/alkaline water episodes in a lacustrine environment. The cementation of siderite, analcime, calcite and albite occluded the substantial porosity in the sandstones at an early diagenetic stage. However, extensive dissolution of analcime cement and labile detrital feldspars occurred during burial diagenesis, resulting in a significant secondary porosity enhancement in the sandstones and making them very good quality oil reservoirs. The origin of secondary porosity is related to the generation of various organic acids due to organic maturation of the interbedded exceptionally organic-rich oil shales.

  14. Diagenesis and secondary porosity enhancement from dissolution of analcime cement in reservoir sandstones: The Upper Permian Pingdiquan Formation, Junggar basin, northwest China

    SciTech Connect

    Zhaohui, T.; Longstaffe, F.J.; Parnell, J.

    1996-12-31

    The Junggar Basin is one of the largest and most important oil-producing basins in China, in which Upper Permian lacustrine oil shales are among the thickest and richest petroleum source rocks in the world. The Upper Permian Pingdiquan Formation was deposited predominantly in fan-delta sequences within a lacustrine setting. The Pingdiquan Formation sandstones constitute the principal oil reservoirs, whereas the interbedded black shales are the predominant oil source rocks. The early diagenetic mineral assemblage in the sandstones comprises siderite, pyrite, analcime, albite, calcite and authigenic quartz as well as trace amount of halite; By contrast, the late diagenetic minerals are characterized by authigenic K-feldspar, ankerite, and minor amounts of mixed-layer clay minerals. Petrographic, mineralogical and available paleoecological data suggest that early authigenic minerals in the sandstones were controlled by alternating periodic fresh water and saline/alkaline water episodes in a lacustrine environment. The cementation of siderite, analcime, calcite and albite occluded the substantial porosity in the sandstones at an early diagenetic stage. However, extensive dissolution of analcime cement and labile detrital feldspars occurred during burial diagenesis, resulting in a significant secondary porosity enhancement in the sandstones and making them very good quality oil reservoirs. The origin of secondary porosity is related to the generation of various organic acids due to organic maturation of the interbedded exceptionally organic-rich oil shales.

  15. Basin-mountain structures and hydrocarbon exploration potential of west Junggar orogen in China

    NASA Astrophysics Data System (ADS)

    Wu, X.; Qi, X.; Zheng, M.

    2015-12-01

    Situated in northern Xinjiang, China, in NE-SW trend, West Junggar Orogen is adjacent to Altai fold belt on the north with the Ertix Fault as the boundary, North Tianshan fold belt on the south with the Ebinur Lake Strike-slip Fault as the boundary, and the Junggar Basin on the southeast with Zaire-Genghis Khan-Hala'alat fold belt as the boundary. Covering an area of about 10×104 km2 in China, there are medium and small intermontane basins, Burqin-Fuhai, Tacheng, Hefeng and Hoxtolgay, distributing inside the orogen. Tectonically West Junggar Orogen lies in the middle section of the Palaeo-Asian tectonic domain where the Siberia, Kazakhstan and Tarim Plates converge, and is the only orogen trending NE-SW in the Palaeo-Asian tectonic domain. Since the Paleozoic, the orogen experienced pre-Permian plate tectonic evolution and post-Permian intra-plate basin evolution. Complex tectonic evolution and multi-stage structural superimposition not only give rise to long term controversial over the basin basement property but also complex basin-mountain coupling relations, structures and basin superimposition modes. According to analysis of several kinds of geological and geophysical data, the orogen was dominated by compressive folding and thrust napping from the Siberia plate in the north since the Late Paleozoic. Compressive stress weakened from north to south, corresponding to subdued vertical movement and enhanced horizontal movement of crustal surface from north to south, and finally faded in the overthrust-nappe belt at the northwest margin of the Junggar Basin. The variation in compressive stress is consistent with the surface relief of the orogen, which is high in the north and low in the south. There are two kinds of basin-mountain coupling relationships, i.e. high angle thrusting and overthrusting and napping, and two kinds of basin superimposition modes, i.e. inherited and progressive, and migrating and convulsionary modes. West Junggar orogen has rich oil and gas

  16. Basin-mountain structures and hydrocarbon exploration potential of west Junggar orogen in China

    NASA Astrophysics Data System (ADS)

    Wu, Xiaozhi; He, Dengfa; Qi, Xuefeng

    2016-04-01

    Situated in northern Xinjiang, China, in NE-SW trend, West Junggar Orogen is adjacent to Altai fold belt on the north with the Ertix Fault as the boundary, North Tianshan fold belt on the south with the Ebinur Lake Strike-slip Fault as the boundary, and the Junggar Basin on the southeast with Zaire-Genghis Khan-Hala'alat fold belt as the boundary. Covering an area of about 10×104 km2 in China, there are medium and small intermontane basins, Burqin-Fuhai, Tacheng, Hefeng and Hoxtolgay, distributing inside the orogen. Tectonically West Junggar Orogen lies in the middle section of the Palaeo-Asian tectonic domain where the Siberia, Kazakhstan and Tarim Plates converge, and is the only orogen trending NE-SW in the Palaeo-Asian tectonic domain. Since the Paleozoic, the orogen experienced pre-Permian plate tectonic evolution and post-Permian intra-plate basin evolution. Complex tectonic evolution and multi-stage structural superimposition not only give rise to long term controversial over the basin basement property but also complex basin-mountain coupling relations, structures and basin superimposition modes. According to analysis of several kinds of geological and geophysical data, the orogen was dominated by compressive folding and thrust napping from the Siberia plate in the north since the Late Paleozoic. Compressive stress weakened from north to south, corresponding to subdued vertical movement and enhanced horizontal movement of crustal surface from north to south, and finally faded in the overthrust-nappe belt at the northwest margin of the Junggar Basin. The variation in compressive stress is consistent with the surface relief of the orogen, which is high in the north and low in the south. There are two kinds of basin-mountain coupling relationships, i.e. high angle thrusting and overthrusting and napping, and two kinds of basin superimposition modes, i.e. inherited and progressive, and migrating and convulsionary modes. West Junggar orogen has rich oil and gas

  17. Formation and Evolution of the Junggar basin basement

    NASA Astrophysics Data System (ADS)

    He, D.

    2015-12-01

    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.Based on the borehole data from over 300 wells drilled into the Carboniferous System, together with the high-resolution gravity and magnetic data (in a 1:50,000 scale), we made a detailed analysis of the basement structure, formation timing and process and later evolution on basis of core geochemical and isotopic analysis. Firstly, we defined the Mahu Precambrian 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 respectively) and intervened three approximately E-W trending retro-arc or inter-arc basin belts from north to south, such as Santanghu-Suosuoquan-Emin, Wucaiwan-Dongdaohaizi-Mahu (Mahu block sunk as a bathyal basin during this phase) and Fukang-western well Pen1 accordingly. Thirdly, the closure of these retro-arc or inter-arc basins gradually toward the south led to the occurrence of collision and amalgamation of the above-mentioned island arcs during the Carboniferous, constituting the basic framework of the Junggar "block". Fourthly, the emplacement of large-scale mantle-derived magmas occurred in the latest Carboniferous or Early Permian. For instance, the well Mahu 5 penetrate the latest Carboniferous basalts with a thickness of over 20m, and these mantle-derived magmas concreted the above-mentioned island arc-collaged body. Therefore, the Junggar basin basement mainly comprises pre-Carboniferous collaged basement, and its formation is characterized by two-stage growth model, involving the

  18. Fluvial sedimentology of a Mesozoic petrified forest assemblage, Shishu Formation, Junggar foreland basin, Xinjiang, China

    SciTech Connect

    McKnight, C.L.; Gan, O.; Carroll, A.R.; Dilcher, D.; Zhao, M.; Liang, Y.H.; Graham, S.A.

    1988-02-01

    The Upper Jurassic(.) Shishu Formation of the eastern Junggar basin, Xinjiang, northwest China, is a fluvial sand unit containing an important assemblage of well-preserved, silicified tree trunks and rooted stumps. Numerous logs, up to 83 ft (25.5 m) long, occur at several levels within a 33.6-ft (10.3 m) stratigraphic section of fluvial sand, gravel, and mud and several paleosol horizons. The uppermost logbearing layer includes a number of rooted tree stumps in growth position, with diameters of up to 8 ft (2.5 m). The maximum root length observed is 40 ft (12.3 m). The trees have been identified by Chinese paleontologists as Cupressinoxylon. The petrified forest assemblage is preserved on the northeast margin of the Mesozoic Junggar foreland basin, a large continental basin subsiding under thrust loading from the south. Logs found within channel gravel units are oriented with their log axes parallel to the channel axis. Sedimentary structures, including epsilon and trough cross-stratification and imbricated channel gravels, indicate paleocurrent flow generally to the south, toward the basin center. The size of the logs suggests the presence of a major fluvial system. The epsilon cross-sets suggest a channel depth of 26 ft (8 m). The oriented silicified logs and their enclosing clastic sediments provide important information on the depositional systems active on the northeastern margin of the Junggar basin in the Late Jurassic(.) time. Hopefully, further detailed study of the fossil trees, including the spacing of the rooted stumps, will provide new information on the paleoecology of Mesozoic forests and the climatic conditions prevailing in the region at the time of deposition.

  19. Tectonic controls on Upper Permian lacustrine oil shales in the Junggar basin, NW China

    SciTech Connect

    Carroll, A.R.; Brassell, S.C.; Graham, S.A. )

    1991-03-01

    Collision of the Tarim craton with the southern margin of Asia during the Late Carboniferous-Early Permian resulted in uplift of an ancestral Tian Shan range and geographic isolation of the previously marine Junggar basin. Dramatic shifts from marine to nonmarine sedimentation took place in both the southern Junggar and northern Tarim basins during the Permina. Paleocurrent analysis indicate that by the Late Permian, coarse-grained sediments in both basins were being supplied predominantly from the area of the Tian Shan. During the Late Permian, the southern Junggar received in excess of 5,000 m of nonmarine sediments, including approximately 1,000 m of laminated, highly organic-rich lacustrine mudstones (oil shales). These deposits commonly have TOCs of 20-30%, and Rock-Eval pyrolitic yields reaching 2,000 mg/g, ranking them among the most prolific petroleum source rocks in the world. Based on a comparison of the distribution of steranes and extended tricyclic terpanes, these Upper Permian oil shales appear to be the primary source of oils in the giant Karamay field in the northwestern Junggar basin. Ancestral uplift of the Tian Shan thus produced a complex tectono-hydrologic partitioning of the Late Permina Junggar basin, which exerted a strong influence on the character of petroleum source rocks deposited within the basin.

  20. Paleomagnetic Results From Triassic Rock Formations of Junggar Basin, NW China

    NASA Astrophysics Data System (ADS)

    Zhao, X.; Li, J.; Guo, R.; Zhang, W.; Yuan, W.

    2015-12-01

    Our knowledge of the kinematics and duration of collisional events between the Chinese blocks and Siberia is still inadequate. Likewise, the accretionary history of the Central Asian fold belt itself is contentious. The primary goal for this study was to address key questions about the geographic positions of the Junggar Basin in Paleozoic and Mesozoic times and its tectonic relationship with other major Asian blocks by generating high-quality paleomagnetically inferred paleolatitudes and basin histories. Another objective is to see what it can tell us about intraplate motions within central Asia and to recognize vertical-axis tectonic rotations in the region. We collected 348 samples from 42 sites in Paleozoic and Mesozoic stratigraphic sections of east Junggar Basin. Useful results were obtained by progressive demagnetization for sandstone samples of Xiaoquan Formation dated paleontologically as mid to late Triassic. The ChRM direction for the Xiaoquan Formation is directed easterly with intermediate to steep downward inclination in geographic coordinates. After tectonic correction, the mean direction of the ChRM becomes northeasterly with intermediate to shallow inclination, which corresponds to a mean paleolatitude of 20.7° within a 95% confidence band of ± 12 degrees. It is obvious from the data that Junggar and other major parts of eastern Asia did not occupy the same relative positions in terms of paleolatitudes in Late Triassic. Paleomagnetic declinations indicate clockwise vertical-axis rotations of R = 98.3° +/- 16° for the Late Triassic rock unit relative to North China Block (NCB), and 12.4° +/- 16.2° relative to South China Block (SCB). The paleomagnetically inferred latitudinal displacements between Junggar and SCB are general statistically insignificant, as well as the rotational data. These data suggest that Junggar Basin may have been very close to SCB during the Triassic time. A plausible cause of the rotation is the westward rotational

  1. Overpressure and Its Relation to Petroleum Accumulation in Southern Edge of Junggar Basin

    NASA Astrophysics Data System (ADS)

    Zhao, G.

    2014-12-01

    Abstract: Measured formation pressure, well- log and mud weight data show that there are overpressures in the southern edge of Junggar basin. Vertically, overpressure distribution is not direct ly related to the burial depth, it is mainly controlled by stratigraphic horizons, especially the lower Tertiary Anjihaihe Formation has the most evident control over the overpressures. Horizontally, overpressure occur in the 3 structural belts in southern edge of the basin, but there are differences in the east and in the west : in the eastern part overpressures occur in the Anjihaihe Formation only, while in the western part, they occur not only in the Anjihaihe Formation, but also in the Shawan and Ziniguanzi Formation. Analyzing the relationship between the well test data and overpressures in the southern edge of Junggar basin, it can be found that the distribution of oil and gas reservoirs are closely related to the overpressures. Being affected by faulting, and due to the differences in mechanism of relationship between overpressures and preservation of oil and gas reservoirs, the distribution of overpressures and oil and gas reservoirs cannot be corresponding to one another. As a whole, however, oil and gas would be ready to be reservoired in the normally pressured zone below the moderately abnormal pressured or overpressures zone, which would, therefore, be the favorable target of petroleum exploration; while the overpressured zone with relatively high formation pressure coefficient is unfavorable for oil/ gas reservoiring.

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

    NASA Astrophysics Data System (ADS)

    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

  3. The relationship between mineral content and acoustic velocity of sandstone reservoirs in Junggar basin

    NASA Astrophysics Data System (ADS)

    Li, Yan; Gu, Hanming

    2015-08-01

    Sandstone reservoirs have generally high porosity in the Shawan formation of the Chunguang oil field, Junggar basin, because they developed in geological conditions of shallow and weak compaction. High porosity always links lower acoustic velocities in sandstone. However, when it is more than a certain value (approximately 27.5%), the porosity is not in accordance with acoustic velocities. In addition, cast thin sections illustrated incoherence between pore types and porosity. Fluids and mineral content are the two main factors changing acoustic velocities. This means that acoustic velocities of the high-porosity sandstone are mainly affected by the mineral content and fluid properties. Hence, data from litho-electric analysis are used to measure velocities of the compression shear waves, and thin sections are used to identify the mineral content. By the application of cross-plot maps, relations of acoustic velocities and mineral contents are proposed. Mineral contents include mainly quartz, feldspar, and tuff. In normal rock physical models, the shale content is calculated from well logs. The mineral grain is often regarded as pure quartz grain or average mineral composition. However, the application of the normal rock physics model will be inaccurate for high-porosity sandstone. Experience regression functions of the velocity model are established to estimate acoustic velocities. Also, mineral content logs could be predicted by using the P-wave acoustic log, and the rock physics model would be enhanced by using these logs of dynamic mineral contents. Shear wave velocity could also be estimated more accurately.

  4. The origin and formation model of Permian dolostones on the northwestern margin of Junggar Basin, China

    NASA Astrophysics Data System (ADS)

    Lu, Xinchuan; Shi, Ji'an; Zhang, Shuncun; Zou, Niuniu; Sun, Guoqiang; Zhang, Shengyin

    2015-06-01

    This study investigates the mechanism of dolostone formation and establishes a dolomitization model in the Permian strata on the northwestern margin of Junggar Basin, China. Dolomitic rock samples are collected from the Permian Fengcheng Formation in Urho area and then characterized by petrological, mineralogical, carbon and oxygen isotope, and trace element geochemical analyses. Results show that the major types of dolomitic rocks include dolomitic mudstone, dolomitic siltstone, dolomitized tuffaceous siltstone, and dolomitized tuffaceous mudstone. The dolomitized rocks are dominated by euhedral or subhedral powder- and fine-crystal dolomites formed by replacement lacustrine argilla-calcareous and siliceous (tuffaceous) components and commonly filled with residual and late calcite cements. The parameters of dolomitic rocks show great variations, including the V/Ni ratio (1.02-4.88), Sr content (95.9-783.6 μg/g), Mg/Ca ratio (0.68-5.13), degree of ordering (0.39-1.00), δ18OPDB (-14.8‰ to 3.2‰), and δ13CPDB (-1‰ to 5.2‰). The dolomitic rocks have multi-stage origins and were formed in a semi-closed continental brackish-saltwater bay with weak hydrodynamic processes, deep water bodies, and relatively quiet conditions. In the Permian depositional stage, a combination of complex tectonic activities, fault development, hot subtropical climate, and frequent volcanic activities provided not only Mg2+ source for dolomitization but also channels for rapid flow and seepage of Mg-rich fluids. The origins of dolostones in the study area include penecontemporaneous dolomitization, burial dolomitization, and hydrothermal dolomitization. This study lays a foundation for further studies on dolomite formation and dolomite reservoir, and provides effective methods for researching complex dolostone (tuffaceous, shale and silty dolomite) formation.

  5. Mesozoic hydrocarbon source rock studies of north Tarim, south Junggar, and Turpan basins, Xinjiang Uygur autonomous region, northwestern China

    SciTech Connect

    Hendrix, M.S.; Xiao, Z.; Liang, Y.; Graham, S.A.; Carroll, A.R.; Chu, J.; McKnight, C.

    1989-03-01

    Ongoing outcrop and accompanying pyrolysis studies of Mesozoic strata of the north Tarim, south Junggar, and Turpan retroarc foreland basins, northwestern China, have demonstrated the existence of potential oil-prone and gas-prone petroleum source rocks. Lithologies include Jurassic coals from all three basins and Triassic coals from Tarim. Jurassic coals collected from the Mesozoic depocenters of the Junggar and Tarim basins are oil prone, yielding S/sub 2//S/sub 2+3/ values that range from 0.80 to 0.99 and average 0.96, hydrogen index (HI) values that range from 117.9 to 213.4 and average 150.8, and oxygen index (OI) values that range from 1.1 to 31.6 and average 7.67. In contrast, Triassic coals of Tarim and Jurassic coals of Turpan contain more conventional type III gas-prone kerogens and yield S/sub 2//S/sub 2+3/ values ranging from 0.04 to 0.52 and averaging 0.22, HI values ranging from 3.2 to 130.2 with a mean of 33.6, and OI values ranging from 30.9 to 223.7 and averaging 115.9. Coals of all three basins are slightly immature to mature with respect to oil generation, as indicated by T/sub max/ values ranging from 425/degrees/ to 449/degrees/C (average = 343/degrees/C) and vitrinite reflectance values ranging from 0.51 to 0.64 (average = 0.57). Thus, given the widespread abundance and significant thicknesses of Mesozoic and especially Jurassic coals in all three basins, it is very likely that Mesozoic contributions to Xinjiang's oil and gas reserves are significant. This is particularly important in the north Tarim basin, where recent Chinese oil and gas discoveries have been made and the existence of significant pre-Mesozoic source beds remains unproven.

  6. A new genus of aplodontid rodent (Mammalia, Rodentia) from the late Oligocene of northern Junggar Basin, China.

    PubMed

    Bi, Shundong; Meng, Jin; McLean, Sarah; Wu, Wenyu; Ni, Xijun; Ye, Jie

    2013-01-01

    A new genus and species of aplodontid rodent, Proansomys dureensis, from the late Oligocene of the northern Junggar Basin of China is described. The new genus is referred to as Ansomyinae because the ectoloph on the upper cheek teeth, although not fully crested, has attained the same characteristic bucket-handle-shaped configuration as other members of the subfamily. It represents the earliest record of the subfamily yet discovered in Asia and is more plesiomorphic than species of the genus Ansomys in having a partly crested ectoloph, a lower degree of lophodonty, and less complex tooth basins (lacking accessory lophules). Proansomys has transitional features between Prosciurus and Ansomys, suggesting that the Ansomyinae derived from a group of aplodontids related to Prosciurus, as did other advanced aplodontid rodents. This provides new light on the paleobiogeography of the Ansomyinae.

  7. Late Paleozoic tectonic evolution of the Central Asian Orogenic Belt: Constraints from multiple arc-basin systems in Altai-Junggar area, NW China

    NASA Astrophysics Data System (ADS)

    Li, D.

    2015-12-01

    In this study, we report results from integrated geological, geophysical and geochemical investigations on the Wulungu Depression of the Junggar Basin to understand the Late Paleozoic continental growth of the Junggar area and its amalgamation history with the Altai terrane, within the broad tectonic evolution of the Altai-Junggar area. Based on seismic and borehole data, the Wulungu Depression can be divided into two NW-trending tectonic units by southward thrust faults. The Suosuoquan Sag is composed of gray basaltic andesite, andesite, tuff, tuffaceous sandstone and tuffite, and the overlying Early Carboniferous volcano-sedimentary sequence with lava gushes and marine sediments from a proximal juvenile provenance, compared to the andesite in the Hongyan High. The SIMS Zircon U-Pb ages for andesites from Late Paleozoic strata indicate that these volcanics in Suosuoquan Sag and Hongyan High erupted at 376.3Ma and 313.4Ma, respectively. Most of the intermediate-mafic volcanic rocks exhibit calc-alkaline affinity, low initial 87Sr/86Sr and positive ɛNd(t) and ɛHf(t) values. Furthermore, these rocks have high Th/Yb and low Ce/Pb and La/Yb ratios as well as variable Ba/Th and Ba/La ratios. These features imply that the rocks were derived from partial melting of a mantle wedge metasomatized by subduction-related components in an island arc setting. The basin filling pattern and the distribution of island arc-type volcanics and their zircon Hf model ages with the eruptive time suggest that the Wulungu Depression represents an island arc-basin system with the development of a Carboniferous retro-arc basin. The gravity and magnetic anomaly data suggest that Altai-Junggar area incorporates three arc-basin belts from north to south: the Karamaili-Luliang-Darbut, Yemaquan-Wulungu, and Dulate-Fuhai-Saur. The recognition of the Wulungu arc-basin system demonstrates that the northern Junggar area is built by amalgamation of multiple Paleozoic linear arcs and accretionary

  8. Late paleozoic tectonic amalgamation of northwestern China. Sedimentary record of the northern Tarim, northwestern Turpan, and southern Junggar basins

    SciTech Connect

    Carroll, A.R.; Graham, S.A.; Hendrix, M.S.; Ying, D.; Zhou, D.

    1995-05-01

    This study focuses on areas adjacent to the Tian Shan (shan is Chinese for mountains) in Xinjiang Uygur Autonomous Region, northwestern China, and provides new field data on Carboniferous and Permian outcrop exposures of sedimentary rocks of the southern Junggar, northwestern Turpan, and northern Tarim basins that bear directly on the history of late Paleozoic tectonic amalgamation. We present here a multifaceted sedimentary basin analysis, including sedimentary facies, paleocurrent, and sandstone provenance analyses, and reconstructions of late Paleozoic basin subsidence. These data provide a unique record not only of the basins themselves, but also of the evolution of the adjacent orogenic belts. This study is based on fieldwork during the summers of 1987, 1988, 1991, and 1992 by workers from Stanford University, the Chinese Academy of Geological Sciences, and the Xinjiang Bureau of Geology and Mineral Resources. Although reconnaissance in nature, the data presented here provide a basis for evaluating alternative hypotheses for the evolution of northwestern China and provide a starting point for more comprehensive future studies. 72 refs., 18 figs., 1 tab.

  9. Petrogenesis of Early-Permian sanukitoids from West Junggar, Northwest China: Implications for Late Paleozoic crustal growth in Central Asia

    NASA Astrophysics Data System (ADS)

    Yin, Jiyuan; Chen, Wen; Xiao, Wenjiao; Yuan, Chao; Sun, Min; Tang, Gongjian; Yu, Shun; Long, Xiaoping; Cai, Keda; Geng, Hongyan; Zhang, Yan; Liu, Xinyu

    2015-11-01

    Sanukitoids and their equivalents are rare subduction-related rock types that have been found in modern arc settings and in Late Archean sequences. The investigation of sanukitoids is of particular importance to a better understanding of crust-forming processes and continental growth. In this paper we report zircon U-Pb and Ar-Ar ages and major element, trace element, and Sr-Nd-Hf isotope data for the Bieluagaxi dioritic pluton and dikes from the southern part of the West Junggar, NW China. These rocks formed in the Early Permian and show a remarkable geochemical affinity with Cenozoic sanukitoids of the Setouchi Volcanic Belt of SW Japan with high Mg# (48-73) values, Cr (54-539 ppm), Ni (21-197 ppm) contents and Th/La (0.15-0.37) ratios and low Sr/Y ratios (16-27) and Sr (263-442 ppm) contents. They may be generated by the partial melting of subducting sediments, and subsequent melt-mantle interaction. Additionally, the sanukitoids are also widespread in the Karamay-Baogutu area of West Junggar accompanied by high Sr (average 713 ppm) contents and Sr/Y (50-130) ratios, and low Y (6.9-12.6 ppm) contents. The difference in petrochemical characteristics between the Baogutu-Karamay and Bieluagaxi sanukitoids can be explained by the difference in depth of initial melting, origin composition and fractional crystallization. The Baogutu-Karamay sanukitoids were probably formed under eclogitic conditions, while the Bieluagaxi sanukitoids were at a shallower depth. Moreover, the compositional similarity between continental-crust forming rocks and the Bieluagaxi sanukitoids suggests that the sanukitoids genesis could be closely related to the process of continental crust formation. The Late Carboniferous-Early Permian sanukitoids in the West Junggar may be an indicator of anomalous thermal activity. Ridge subduction may play a crucial role in the evolution and growth of the continental crust in Central Asia.

  10. [Contamination Assessment and Sources Analysis of Soil Heavy Metals in Opencast Mine of East Junggar Basin in Xinjiang].

    PubMed

    Liu, Wei; Yang, Jian-jun; Wang, Jun; Wang, Guo; Cao, Yue-e

    2016-05-15

    The opencast mine of East Junggar Basin in Xinjiang is the largest self-contained coalfield in China, and the ecological environment of the opencast is very fragile because of its arid climate and poor soil. In this study, 50 soil samples (from 0 to 30 cm depth soil at intervals of 10 cm) in opencast Mine of East Junggar Basin in Xinjiang were collected in order to explore the heavy metals contamination of the coal mining. The contents of zinc (Zn), copper (Cu), cadmium (Cr), lead (Pb), mercury (Hg) and arsenic (As) were measured and the degree of pollution was assessed by Nemerow index, geo-accumulation (Igeo) index and potential ecological risk index. In addition, the layered comparison, dust fall and the distance between coal mine and samples location were used to analyze the source of heavy metals contamination. The results showed that value of As surpassed the Chinese soil quality standard class I (GB 15618-1995) mostly severely, followed by Cr, a relatively lower surpass was obtained by Hg and Cu, while Zn and Pb did not surpass the standard. According to the standard, the soil heavy metals content of research region was in light pollution status and the pollution index for each heavy metal followed the order of As (2.07) > Cr (0.95) > Cu (0.55) > Zn (0.48) > Hg (0.45) > Pb (0.38), which demonstrated a heavy pollution of As and clean status of others. Additionally, an Igeo value of 1.14 for Hg reflected a moderated pollution. The major contribution factor was Hg with a risk index of 251.40. The source analysis showed that the content of Pb in the surface soil (10-20 cm) was different from that in the deep layer (20-30 cm), which may be caused by coal combustion and other human activities. The sources of Hg and As were similar and may come from coal combustion. The distance to the mining area was not the major factor affecting the diffusion of heavy metals, other candidate factors included terrain, aspect and wind direction, etc. PMID:27506051

  11. [Contamination Assessment and Sources Analysis of Soil Heavy Metals in Opencast Mine of East Junggar Basin in Xinjiang].

    PubMed

    Liu, Wei; Yang, Jian-jun; Wang, Jun; Wang, Guo; Cao, Yue-e

    2016-05-15

    The opencast mine of East Junggar Basin in Xinjiang is the largest self-contained coalfield in China, and the ecological environment of the opencast is very fragile because of its arid climate and poor soil. In this study, 50 soil samples (from 0 to 30 cm depth soil at intervals of 10 cm) in opencast Mine of East Junggar Basin in Xinjiang were collected in order to explore the heavy metals contamination of the coal mining. The contents of zinc (Zn), copper (Cu), cadmium (Cr), lead (Pb), mercury (Hg) and arsenic (As) were measured and the degree of pollution was assessed by Nemerow index, geo-accumulation (Igeo) index and potential ecological risk index. In addition, the layered comparison, dust fall and the distance between coal mine and samples location were used to analyze the source of heavy metals contamination. The results showed that value of As surpassed the Chinese soil quality standard class I (GB 15618-1995) mostly severely, followed by Cr, a relatively lower surpass was obtained by Hg and Cu, while Zn and Pb did not surpass the standard. According to the standard, the soil heavy metals content of research region was in light pollution status and the pollution index for each heavy metal followed the order of As (2.07) > Cr (0.95) > Cu (0.55) > Zn (0.48) > Hg (0.45) > Pb (0.38), which demonstrated a heavy pollution of As and clean status of others. Additionally, an Igeo value of 1.14 for Hg reflected a moderated pollution. The major contribution factor was Hg with a risk index of 251.40. The source analysis showed that the content of Pb in the surface soil (10-20 cm) was different from that in the deep layer (20-30 cm), which may be caused by coal combustion and other human activities. The sources of Hg and As were similar and may come from coal combustion. The distance to the mining area was not the major factor affecting the diffusion of heavy metals, other candidate factors included terrain, aspect and wind direction, etc.

  12. Origin of dolomitic rocks in the lower Permian Fengcheng formation, Junggar Basin, China: evidence from petrology and geochemistry

    NASA Astrophysics Data System (ADS)

    Zhu, Shifa; Qin, Yi; Liu, Xin; Wei, Chengjie; Zhu, Xiaomin; Zhang, Wei

    2016-09-01

    Although dolomitization of calcite minerals and carbonatization of volcanic rocks have been studied widely, the extensive dolomitic rocks that originated from altered volcanic and volcaniclastic rocks have not been reported. The dolomitic rocks of the Fengcheng Formation in the Junggar Basin of China appear to be formed under unusual geologic conditions. The petrological and geochemical characteristics indicate that the dolomitizing host rock is devitrified volcanic tuff. After low-temperature alteration and calcitization, these tuffaceous rocks are replaced by Mg-rich brine to form massive dolomitic tuffs. We propose that the briny (with -2 ‰ ~ 6 ‰ of δ13CPDB and -5 ‰ ~ 4 ‰ of δ18OPDB) and Mg-rich marine formation water (with 0.7060 ~ 0.7087 of 87Sr/86Sr ratio), the thick and intermediate-mafic volcanic ashes, and the tectonically compressional movement may have favored the formation of the unusual dolomitic rocks. We conclude that the proposed origin of the dolomitic rocks can be extrapolated to other similar terranes with volcaniclastic rocks, seabed tuffaceous sediment, and fracture filling of sill.

  13. 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

    NASA Astrophysics Data System (ADS)

    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

  14. Geochemical characteristics of crude oil from a tight oil reservoir in the Lucaogou Formation, Jimusar Sag, Junggar Basin

    NASA Astrophysics Data System (ADS)

    Cao, Z.

    2015-12-01

    Jimusar Sag, which lies in the Junggar Basin,is one of the most typical tight oil study areas in China. However, the properties and origin of the crude oil and the geochemical characteristics of the tight oil from the Lucaogou Formation have not yet been studied. In the present study, 23 crude oilsfrom the Lucaogou Formation were collected for analysis, such as physical properties, bulk composition, saturated hydrocarbon gas chromatography-mass spectrometry (GC-MS), and the calculation of various biomarker parameters. In addition,source rock evaluation and porosity permeability analysis were applied to the mudstones and siltstones. Biomarkers of suitable source rocks (TOC>1, S1+S2>6mg/g, 0.7%basin modeling was performed. The oil-filling history was also defined by means of basin modeling and microthermometry. The results indicated the presence of low maturity to mature crude oils originating from the burial of terrigenous organic matter beneath a saline lake in the source rocks of mainly type II1kerogen. In addition, a higher proportion of bacteria and algae was shown to contribute to the formation of crude oil in the lower section when compared with the upper section of the Lucaogou Formation. Oil-source correlations demonstrated that not all mudstones within the Lucaogou Formation contributed to oil accumulation.Crude oil from the upper and lower sections originated from thin-bedded mudstones interbedded within sweet spot sand bodies. A good coincidence of filling history and hydrocarbon generation history indicated that the Lucaogou reservoir is a typical in situ reservoir. The mudstones over or beneath the sweet spot bodies consisted of natural caprocks and prevented the vertical movement of oil by capillary forces. Despite being thicker, the thick-bedded mudstone between the upper and lower sweet spots had no obvious contribution to

  15. Origin and accumulation mechanisms of petroleum in the Carboniferous volcanic rocks of the Kebai Fault zone, Western Junggar Basin, China

    NASA Astrophysics Data System (ADS)

    Chen, Zhonghong; Zha, Ming; Liu, Keyu; Zhang, Yueqian; Yang, Disheng; Tang, Yong; Wu, Kongyou; Chen, Yong

    2016-09-01

    The Kebai Fault zone of the West Junggar Basin in northwestern China is a unique region to gain insights on the formation of large-scale petroleum reservoirs in volcanic rocks of the western Central Asian Orogenic Belt. Carboniferous volcanic rocks are widespread in the Kebai Fault zone and consist of basalt, basaltic andesite, andesite, tuff, volcanic breccia, sandy conglomerate and metamorphic rocks. The volcanic oil reservoirs are characterized by multiple sources and multi-stage charge and filling history, characteristic of a complex petroleum system. Geochemical analysis of the reservoir oil, hydrocarbon inclusions and source rocks associated with these volcanic rocks was conducted to better constrain the oil source, the petroleum filling history, and the dominant mechanisms controlling the petroleum accumulation. Reservoir oil geochemistry indicates that the oil contained in the Carboniferous volcanic rocks of the Kebai Fault zone is a mixture. The oil is primarily derived from the source rock of the Permian Fengcheng Formation (P1f), and secondarily from the Permian Lower Wuerhe Formation (P2w). Compared with the P2w source rock, P1f exhibits lower values of C19 TT/C23 TT, C19+20TT/ΣTT, Ts/(Ts + Tm) and ααα-20R sterane C27/C28 ratios but higher values of TT C23/C21, HHI, gammacerane/αβ C30 hopane, hopane (20S) C34/C33, C29ββ/(ββ + αα), and C29 20S/(20S + 20R) ratios. Three major stages of oil charge occurred in the Carboniferous, in the Middle Triassic, Late Triassic to Early Jurassic, and in the Middle Jurassic to Late Jurassic periods, respectively. Most of the oil charged during the first stage was lost, while moderately and highly mature oils were generated and accumulated during the second and third stages. Oil migration and accumulation in the large-scale stratigraphic reservoir was primarily controlled by the top Carboniferous unconformity with better porosity and high oil enrichment developed near the unconformity. Secondary dissolution

  16. Thermal history of the periphery of the Junggar Basin, Northwestern China

    USGS Publications Warehouse

    King, J.D.; Yang, J.; Pu, F.

    1994-01-01

    Geochemical analysis of rock core samples show that the basin periphery has experienced low thermal stress; present-day heat flows are in the range of 25-35 mW/m2 and have not been significantly higher than the worldwide mean of approx. 63 mW/m2 since the mid-Permian. Present day heat flows were determined from corrected borehole temperatures and rock thermal conductivities. Paleo-heat flows were determined by first-order reaction kinetic modeling of several geochemical paleothermometers (vitrinite reflectance, clay mineral diagenesis and relative proportions of sterane and hopane biological marker diastereomers). ?? 1994.

  17. Mesozoic reactivated transpressional structures and multi-stage tectonic deformation along the Hong-Che fault zone in the northwestern Junggar Basin, NW China

    NASA Astrophysics Data System (ADS)

    Yu, Yangli; Wang, Xin; Rao, Gang; Wang, Renfu

    2016-06-01

    The recognition of paleo-strike-slip faulting is often difficult, particularly when the associated structures are presently inactive and covered by thick sediments. Fortunately, high-resolution 3D seismic reflection data can provide a powerful tool to solve this problem. In this study, we focus on the structural features and tectonic evolution of Hong-Che fault system, a paleo-strike-slip fault zone recognized in the NW margin of Junggar Basin by using the 2D and 3D seismic data. The results of our analysis demonstrate that: 1) The Middle Triassic to Jurassic dextral transpressional structures were developed along Hong-Che fault zone, which are characterized by the restraining bend on the southern segment, the highly localized shearing deformation on the central segment, and the horsetail splay faulting of a fault tip zone on the northern segment; 2) The Hong-Che fault zone had also experienced the Early Permian rifting and the Late Permian-Early Triassic tectonic inversion, which probably played important roles in controlling the subsequent tectonic deformation; and 3) The demonstrated dextral strike-slip faulting is consistent with the Middle Triassic-Jurassic deformation in the Ke-Bai, Wu-Xia, and Irtysh fault zones, and therefore supports the counterclockwise rotation of Junggar Basin, which might be the far-field effect of the collision between Qiangtang block and Songpan-Ganzi terrane in the Triassic. The results of this study also prove that high-resolution seismic reflection data can serve as a useful tool for investigating the buried paleo-structures.

  18. View northwest, discharge basin, floor, showing cement cross beams built ...

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

    View northwest, discharge basin, floor, showing cement cross beams built on stone bases - Glens Falls Feeder, Sluice, Along south side of Glens Falls Feeder between locks 10 & 20, Hudson Falls, Washington County, NY

  19. AERIAL VIEW, LOOKING NORTH NORTHWEST, OF ARRASTRA BASIN, SILVER LAKE, ...

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

    AERIAL VIEW, LOOKING NORTH NORTHWEST, OF ARRASTRA BASIN, SILVER LAKE, AND THE SHENANDOAH-DIVES (MAYFLOWER) MILL IN DISTANT ANIMAS VALLEY. - Shenandoah-Dives Mill, 135 County Road 2, Silverton, San Juan County, CO

  20. Organic petrology and geochemistry of mudrocks from the lacustrine Lucaogou Formation, Santanghu Basin, northwest China: Application to lake basin evolution

    USGS Publications Warehouse

    Hackley, Paul C.; Fishman, Neil; Wu, Tao; Baugher, Gregory

    2016-01-01

    Exploration for tight oil in the frontier Santanghu Basin of northwest China has resulted in recent commercial discoveries sourced from the lacustrine Upper Permian Lucaogou Formation, already considered a “world class source rock” in the Junggar Basin to the west. Here we apply an integrated analytical program to carbonate-dominated mudrocks from the Lucaogou Formation in Santanghu Basin to document the nature of organic matter (OM) in the context of an evolving lake system. The organic-rich samples (TOC 2.8–11.4 wt%; n = 10) were widely spaced from an ~ 200 m cored section, interpreted from textural and mineralogical evidence to document transition from a lower under-filled to an overlying balanced-filled lake. Organic matter is dominated by moderate to strongly fluorescent amorphous material with Type I geochemical signature (HI values 510–755; n = 10) occurring in a continuum from lamellar stringers, 10–20 μm thick, some ≥ 1 mm in length (possible microbial mat; preserved only in lower under-filled section) to finely-disseminated amorphous groundmass intimately intermixed with mineral matrix. Biomarkers for methanotrophs and photosynthetic cyanobacteria indicate a complex microbial consortium. A unicellular prasinophyte green alga(?), similar to Tasmanites in marine rocks, is present as discrete flattened discs 50–100 μm in diameter. Type III OM including vitrinite (some fluorescent) and inertinite also is abundant. Solid bitumen, indicating local kerogen conversion, fills voids and occurs throughout the cored section. Vitrinite reflectance values are 0.47–0.58%, consistent with strong OM fluorescence but may be “suppressed”. Other proxies, e.g., biomarker parameters, indicate the Lucaogou Formation is in the early oil window at this location. On average, slightly more amorphous OM and telalginite are present in the lower section, consistent with a shallow, stratified, saline environment with low sediment dilution. More

  1. Triassic-Jurassic climate in continental high-latitude Asia was dominated by obliquity-paced variations (Junggar Basin, Ürümqi, China).

    PubMed

    Sha, Jingeng; Olsen, Paul E; Pan, Yanhong; Xu, Daoyi; Wang, Yaqiang; Zhang, Xiaolin; Yao, Xiaogang; Vajda, Vivi

    2015-03-24

    Empirical constraints on orbital gravitational solutions for the Solar System can be derived from the Earth's geological record of past climates. Lithologically based paleoclimate data from the thick, coal-bearing, fluvial-lacustrine sequences of the Junggar Basin of Northwestern China (paleolatitude ∼60°) show that climate variability of the warm and glacier-free high latitudes of the latest Triassic-Early Jurassic (∼198-202 Ma) Pangea was strongly paced by obliquity-dominated (∼40 ky) orbital cyclicity, based on an age model using the 405-ky cycle of eccentricity. In contrast, coeval low-latitude continental climate was much more strongly paced by climatic precession, with virtually no hint of obliquity. Although this previously unknown obliquity dominance at high latitude is not necessarily unexpected in a high CO2 world, these data deviate substantially from published orbital solutions in period and amplitude for eccentricity cycles greater than 405 ky, consistent with chaotic diffusion of the Solar System. In contrast, there are indications that the Earth-Mars orbital resonance was in today's 2-to-1 ratio of eccentricity to inclination. These empirical data underscore the need for temporally comprehensive, highly reliable data, as well as new gravitational solutions fitting those data. PMID:25759439

  2. Triassic-Jurassic climate in continental high-latitude Asia was dominated by obliquity-paced variations (Junggar Basin, Ürümqi, China).

    PubMed

    Sha, Jingeng; Olsen, Paul E; Pan, Yanhong; Xu, Daoyi; Wang, Yaqiang; Zhang, Xiaolin; Yao, Xiaogang; Vajda, Vivi

    2015-03-24

    Empirical constraints on orbital gravitational solutions for the Solar System can be derived from the Earth's geological record of past climates. Lithologically based paleoclimate data from the thick, coal-bearing, fluvial-lacustrine sequences of the Junggar Basin of Northwestern China (paleolatitude ∼60°) show that climate variability of the warm and glacier-free high latitudes of the latest Triassic-Early Jurassic (∼198-202 Ma) Pangea was strongly paced by obliquity-dominated (∼40 ky) orbital cyclicity, based on an age model using the 405-ky cycle of eccentricity. In contrast, coeval low-latitude continental climate was much more strongly paced by climatic precession, with virtually no hint of obliquity. Although this previously unknown obliquity dominance at high latitude is not necessarily unexpected in a high CO2 world, these data deviate substantially from published orbital solutions in period and amplitude for eccentricity cycles greater than 405 ky, consistent with chaotic diffusion of the Solar System. In contrast, there are indications that the Earth-Mars orbital resonance was in today's 2-to-1 ratio of eccentricity to inclination. These empirical data underscore the need for temporally comprehensive, highly reliable data, as well as new gravitational solutions fitting those data.

  3. Triassic–Jurassic climate in continental high-latitude Asia was dominated by obliquity-paced variations (Junggar Basin, Ürümqi, China)

    PubMed Central

    Sha, Jingeng; Olsen, Paul E.; Pan, Yanhong; Xu, Daoyi; Wang, Yaqiang; Zhang, Xiaolin; Yao, Xiaogang; Vajda, Vivi

    2015-01-01

    Empirical constraints on orbital gravitational solutions for the Solar System can be derived from the Earth’s geological record of past climates. Lithologically based paleoclimate data from the thick, coal-bearing, fluvial-lacustrine sequences of the Junggar Basin of Northwestern China (paleolatitude ∼60°) show that climate variability of the warm and glacier-free high latitudes of the latest Triassic–Early Jurassic (∼198–202 Ma) Pangea was strongly paced by obliquity-dominated (∼40 ky) orbital cyclicity, based on an age model using the 405-ky cycle of eccentricity. In contrast, coeval low-latitude continental climate was much more strongly paced by climatic precession, with virtually no hint of obliquity. Although this previously unknown obliquity dominance at high latitude is not necessarily unexpected in a high CO2 world, these data deviate substantially from published orbital solutions in period and amplitude for eccentricity cycles greater than 405 ky, consistent with chaotic diffusion of the Solar System. In contrast, there are indications that the Earth–Mars orbital resonance was in today’s 2-to-1 ratio of eccentricity to inclination. These empirical data underscore the need for temporally comprehensive, highly reliable data, as well as new gravitational solutions fitting those data. PMID:25759439

  4. 6. Aerial view, looking northwest, showing former boat basin on ...

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

    6. Aerial view, looking northwest, showing former boat basin on east side of island, A-Frame of sidewheeler Minerva Ex Jane Moseley (vessel 53) to left, and package freighter (vessel 54) in center Charles Wisniewski, photographer, January 1985 - Shooters Island, Ships Graveyard, Newark Bay, Staten Island (subdivision), Richmond County, NY

  5. A review of the geological characteristics and geodynamic setting of Late Paleozoic porphyry copper deposits in the Junggar region, Xinjiang Uygur Autonomous Region, Northwest China

    NASA Astrophysics Data System (ADS)

    Yang, Fuquan; Mao, Jingwen; Pirajno, Franco; Yan, Shenghao; Liu, Guoren; Zhou, Gang; Zhang, Zhixin; Liu, Feng; Geng, Xinxia; Guo, Chunli

    2012-04-01

    In this review, we describe the geological characteristics of porphyry copper deposits in Junggar region, Xinjiang, and place these into their metallogenic-tectonic context. These porphyry copper deposits are mainly found in four metallogenic belts: (1) a Late Silurian to Early Devonian Cu-Mo metallogenic belt in the Qiongheba area; (2) the Late Devonian Kalaxiange'er Cu metallogenic belt; (3) the Early Carboniferous Xilekuduke-Suoerkuduke porphyry-skarn Cu-Mo metallogenic belt; and (4) the Late Carboniferous Baogutu porphyry Cu metallogenic belt. The ages of mineralization can be divided into three broad intervals: <427-409 Ma, 378-374 Ma and 327-310 Ma. Homogenization temperatures of fluid inclusions in the porphyry copper deposits range mainly from 300 to 180 °C. Salinity ranges from 0.5 to 21.7 wt.% NaCl equiv and 28.9 to 66.76 wt.% NaCl equiv. Ore-forming fluids in the Baogutu and Yunyingshan deposits in the Baogutu and Qiongheba belts, were mainly derived from magmatic fluids, whereas those in the Halasu, Yulekenhalasu and Xilekuduke deposits in the Kalaxiange'er and Xilekuduke-Suoerkuduke belts were mainly derived from magmatic fluids, with some contributions from meteoric water. Sulfur isotope compositions of some porphyry copper deposits cluster around 0‰, indicating that the sulfur was probably derived from mantle-related magmas. The ore-forming processes in all porphyry copper deposits are closely related to the emplacement of intermediate, intermediate-felsic and felsic porphyry intrusions. Porphyry copper deposits in Junggar region developed in a range of tectonic regimes including continental arc, ocean island arc and post collisional settings.

  6. Obliquity-Dominated High-Latitude Continental Triassic-Jurassic Climate, from the Coal-Bearing Junggar Basin, (Ürümqi, China)

    NASA Astrophysics Data System (ADS)

    Olsen, P. E.; Sha, J.; Pan, Y.; Xu, D.; Yao, X.; Wang, Y.; Zhang, X.

    2014-12-01

    Sedimentary facies-based climate proxy data from the thick, coal-bearing, fluvial-lacustrine Haojiagou and Badaowan fms. of the high-paleolatitude (55-65° N) Junggar Basin of northwestern China show that Late Triassic and Early Jurassic (~210-190 Ma) high latitude climate variability was strongly paced by obliquity cycle-dominated (~40-50 ky) orbital variations (1), based on an age model using the 405 ky cycle of eccentricity and the end-Triassic extinction tie point (2,3). In contrast, contemporaneous low-latitude continental climate was nearly exclusively paced by climatic precession, with virtually no hint of obliquity (4). While obliquity-dominance at high latitude is not necessarily unexpected, the envelope of variability of eccentricity, as well as its period (for cycles > 405 ky) at both high and low latitudes deviate in major ways from the expectations of current numerical solutions of orbital variations (5), but is consistent with chaotic diffusion of the Solar System (6), while our preliminary data also suggest that the Earth-Mars orbital secular resonance was in today's 2-to-1 ratio of eccentricity to inclination periods (5). Previously unknown, this obliquity-dominated, non-analog climate variation in the apparently warm and glacier-free high-latitudes of Pangea, coupled with documented low-latitude climatic precession-dominated climate variation, provides a glimpse of an empirical basis for mapping the behavior of the Solar System during times when its behavior was significantly different than present day. This is a contribution to IGCP 632 (Continental crises of the Jurassic). 1, Sha+, 2010, Earth Sci. Frontiers 17:22; 2, Sha+, 2011, Acta Geol. Sinica 85:421; 3, Blackburn+, 2013, Science 340:941; 4, Olsen & Kent, 1996, Palaeogeo. Palaeoclim. Palaeoeco. 122:1; 5, Laskar+, 2011, A&A 532:A89 DOI:10.1051/0004-6361/201116836; 6, Laskar, 1999, Phil. Trans. Roy. Soc. London A 357:1735.

  7. The southern Bonaparte Gulf, northwest Australia - A basin model

    SciTech Connect

    Dauzacker, M.V. Durrant, J.M.; France, R. ); Nilsen, T. )

    1990-05-01

    The Bonaparte Gulf basin Palaeozoic rift is an extension of the Petrel subbasin-Sahul syncline trend forming one arm of a rift triple junction, Salt tectonics developed in this rift setting are fundamental to a new model of the basin and have influenced the development of three Palaeozoic megasequences defined in the model. Megasequence I (MS-I), Silurian-Devonian restricted, synrift sedimentation was associated with extensive evaporitic systems which developed rich source rocks and massive halites. Early basinward salt withdrawal influenced sediment distribution and structuring, localizing shallow-water carbonates above deep salt ridges. Megasequence II (MS-Il) Late Devonian-Late Carboniferous sedimentation is restricted to subbasins formed by continued basinward salt withdrawal. Turbidites were channelled and stacked along subbasin axes during active subsidence (Milligans Formation), and shallow-water carbonate banks continued to develop on basin highs. As subsidence eased, eustatically controlled deltaic sedimentation filled the subbasins, culminating in deposition of a regional shallow-water carbonate (Tanmurra Formation). Continued salt withdrawal in the north produced a carbonate shelf break evidenced by the apparent termination of the Tanmurra Formation seismic reflector, coincident with the carbonate complex development which exhibits continued growth until this period. An overlying unit (Point Spring Sandstone) marks the transition to the next megasequence. Megasequence III (MS-Ill) Late Carboniferous-Late Permian marginal marine/fluvial sedimentation is associated with renewed rifting in the northwest. Associated driving subsidence produced northwest tilting, which was reinforced by Mesozoic-Cenozoic passive margin subsidence following the Late Jurassic continental breakup and abandonment of the northwest-southeast Paleozoic rift arm.

  8. Remote sensing studies of the terrain northwest of Humorum basin

    NASA Technical Reports Server (NTRS)

    Hawke, B. R.; Peterson, Chris A.; Lucey, Paul G.; Taylor, G. J.; Blewett, David T.; Campbell, Bruce A.; Coombs, Cassandra R.; Spudis, Paul D.

    1993-01-01

    We have used near-infrared reflectance spectra and Earth-based radar data to investigate the composition and origin of the various geologic units northwest of Humorum basin as well as the stratigraphy of the Humorum preimpact target site. The results of our spectral analysis indicate that at least a portion of the inner, mare-bounding ring is composed of pure anorthosite. Other highlands units in the region are dominated by noritic anorthosite. The anorthosites on the inner ring may have been derived from a layer of anorthosite that exists at depth beneath a more pyroxene-rich unit. Both Gassendi G and F craters expose mare material from beneath a highlands-rich surface unit that was emplaced as a result of the Letronne, Gassendi, and other impact events. This ancient basalt unit was emplaced after the formation of Humorum basin but prior to the Orientale impact.

  9. 1. OVERALL VIEW OF FLOCCULATION/SEDIMENTATION BASINS (#1778), LOOKING NORTHWEST ...

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

    1. OVERALL VIEW OF FLOCCULATION/SEDIMENTATION BASINS (#1778), LOOKING NORTHWEST - Presidio Water Treatment Plant, Flocculation-Sedimentation Basins, East of Lobos Creek at Baker Beach, San Francisco, San Francisco County, CA

  10. Tectonic evolution of Kashmir basin in northwest Himalayas

    NASA Astrophysics Data System (ADS)

    Alam, Akhtar; Ahmad, Shabir; Bhat, M. Sultan; Ahmad, Bashir

    2015-06-01

    Geomorphology has long been recognised as a key to evaluate the interplay between tectonics and landscape geometry in the regions of active deformation. We use geomorphic signatures at varied spatial scales interpreted from SRTM-DEM/Landsat-ETM data, supplemented with field observations to review the tectonic evolution of Kashmir basin in northwest Himalayas. Geomorphic evidence is persuasive of a credible NNW-SSE trending dextral strike-slip structure (central Kashmir Fault - CKF), with the strike length of ~ 165 km, stretched centrally over the NNW-SSE length of the Kashmir basin. As a result of the strike-slip motion and subsequent erosion, significant deformation has taken place along the CKF. In addition, broad geomorphic architecture of the basin reveals typical pull-apart characteristics. Hence, we deduce that the Kashmir basin has evolved as a pull-apart Quaternary sediment depression owing to the deformation along the central Kashmir Fault. The spatial distribution pattern of seismic events (NEIC-catalogue, 1973-2013) and GPS measurements (published), collectively substantiate our geomorphic interpretations.

  11. Sedimentary basin framework of Exmouth Plateau, northwest Australia

    SciTech Connect

    Boyd, R.; Exon, N.; Williamson, P.

    1987-05-01

    The Exmouth Plateau is a marginal plateau lying off northwest Australia. Water depths range between 800 m and 4000 m, and the area shallower than 2000 m covers approximately 150,000 km/sup 2/. The plateau consists of rifted and deeply subsided continental crust, with a Phanerozoic sedimentary sequence around 10 km thick, deposited in the Canning and Carnarvon basins. The plateau is separated from the Northwest Shelf by the Kangaroo syncline and is bounded to the north, west, and south by oceanic crust of Cretaceous and Jurassic age. The present structural configuration of Exmouth Plateau was initiated by rifting in the Triassic to Middle Jurassic, followed by northwest-oriented sea floor spreading. The western margin has a normal rifted structure, while the southern margin structure was dominated by transform motion. The complex rifted and sheared northern margin contains at least one crustal block of post-breakup igneous origin. Below a rift onset unconformity of Neocomian age lies a thick Triassic paralic sequence to the south, while farther north the unconformity is of Callovian age and overlies a Jurassic sequence of Tethyan carbonates, coal measures, and volcanics. The post-breakup sequence consists of Late Jurassic-Cenomanian deltaic and shelf clastics, overlain by thin Late Cretaceous-Tertiary shallow marine to pelagic carbonates. Exmouth Plateau therefore represents classic rift to mature ocean stage development of a sediment-starved passive margin. The large fault blocks in the rifted Triassic-Jurassic sequences and large areal closures in the Cretaceous deltas encouraged petroleum exploration over the last two decades. The rifted section was shown to be gas prone, while the overlying section proved to be largely immature.

  12. Maturation history modeling of Sufyan Depression, northwest Muglad Basin, Sudan

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Liu, Luofu; An, Fuli; Wang, Hongmei; Pang, Xiongqi

    2016-08-01

    The Sufyan Depression is located in the northwest of Muglad Basin and is considered as a favorable exploration area by both previous studies and present oil shows. In this study, 16 wells are used or referred, the burial history model was built with new seismic, logging and well data, and the thermal maturity (Ro, %) of proved AG source rocks was predicted based on heat flow calculation and EASY %Ro modeling. The results show that the present heat flow range is 36 mW/m2∼50 mW/m2 (average 39 mW/m2) in 13 wells and 15 mW/m2∼55 mW/m2 in the whole depression. Accordingly, the geothermal gradient is 20 °C/km∼26 °C/km and 12 °C/km∼30 °C/km, respectively. The paleo-heat flow has three peaks, namely AG-3 period, lower Bentiu period and Early Paleogene, with the value decreases from the first to the last, which is corresponding to the tectonic evolution history. Corresponding to the heat flow distribution feature, the AG source rocks become mature earlier and have higher present marurity in the south area. For AG-2_down and AG-3_up source rocks that are proved to be good-excellent, most of them are mature with Ro as 0.5%-1.1%. But they can only generate plentiful oil and gas to charge reservoirs in the middle and south areas where their Ro is within 0.7%-1.1%, which is consistent with the present oil shows. Besides, the oil shows from AG-2_down reservoir in the middle area of the Sufyan Depression are believed to be contributed by the underlying AG-3_up source rock or the source rocks in the south area.

  13. Maturation history modeling of Sufyan Depression, northwest Muglad Basin, Sudan

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Liu, Luofu; An, Fuli; Wang, Hongmei; Pang, Xiongqi

    2016-08-01

    The Sufyan Depression is located in the northwest of Muglad Basin and is considered as a favorable exploration area by both previous studies and present oil shows. In this study, 16 wells are used or referred, the burial history model was built with new seismic, logging and well data, and the thermal maturity (Ro, %) of proved AG source rocks was predicted based on heat flow calculation and EASY %Ro modeling. The results show that the present heat flow range is 36 mW/m2˜50 mW/m2 (average 39 mW/m2) in 13 wells and 15 mW/m2˜55 mW/m2 in the whole depression. Accordingly, the geothermal gradient is 20 °C/km˜26 °C/km and 12 °C/km˜30 °C/km, respectively. The paleo-heat flow has three peaks, namely AG-3 period, lower Bentiu period and Early Paleogene, with the value decreases from the first to the last, which is corresponding to the tectonic evolution history. Corresponding to the heat flow distribution feature, the AG source rocks become mature earlier and have higher present marurity in the south area. For AG-2_down and AG-3_up source rocks that are proved to be good-excellent, most of them are mature with Ro as 0.5%-1.1%. But they can only generate plentiful oil and gas to charge reservoirs in the middle and south areas where their Ro is within 0.7%-1.1%, which is consistent with the present oil shows. Besides, the oil shows from AG-2_down reservoir in the middle area of the Sufyan Depression are believed to be contributed by the underlying AG-3_up source rock or the source rocks in the south area.

  14. Mesoscale variability of deep currents in the Northwest Pacific Basin

    NASA Astrophysics Data System (ADS)

    Miyamoto, M.; Oka, E.; Yanagimoto, D.; Fujio, S.; Kurogi, M.; Hasumi, H.

    2014-12-01

    mooring observations conducted near 30°N, 146°40'E in the late 1970's. In the Northwest Pacific Basin, simulated EKE was highest at the Kuroshio Extension, and a high-EKE area extended about 500 km north and south of it.

  15. Assessment of undiscovered conventional oil and gas resources of Bonaparte Basin, Browse Basin, Northwest Shelf, and Gippsland Basin Provinces, Australia, 2011

    USGS Publications Warehouse

    Pollastro, Richard M.; Brownfield, Michael E.; Charpentier, Ronald R.; Cook, Troy A.; Klett, Timothy R.; Kirschbaum, Mark A.; Pitman, Janet K.; Schenk, Christopher J.

    2012-01-01

    Using a geology-based assessment methodology, the U.S. Geological Survey estimated means of 4.7 billion barrels of undiscovered oil and 227 trillion cubic feet of undiscovered natural gas in three major offshore petroleum basins of northwest Australia and in the Gippsland Basin of southeast Australia.

  16. Remote sensing and geologic studies of the terrain northwest of Humorum basin

    NASA Technical Reports Server (NTRS)

    Hawke, B. Ray; Peterson, C. A.; Lucey, P. G.; Taylor, G. J.; Bell, Jeffrey F.; Blewett, D.; Campbell, B.; Coombs, Cassandra R.; Spudis, P. D.

    1991-01-01

    A portion of the highlands terrain northwest of the Humorum basin, a large multiringed impact structure on the southwestern portion of the lunar nearside, exhibits anomalous characteristics in several remote sensing data sets. A variety of remote sensing studies of the terrain northwest of Humorum basin were performed in order to determine the composition and origin of the anomalous unit as well as the composition of the highland material exposed by the Humorum impact event. It was found that at least a portion of the mare-bounding ring of Humorum is composed of pure anorthosite. Other details of the study are reported.

  17. Tectonic evolution of the Tualatin basin, northwest Oregon, as revealed by inversion of gravity data

    USGS Publications Warehouse

    McPhee, Darcy K.; Langenheim, Victoria E.; Wells, Ray; Blakely, Richard J.

    2014-01-01

    The Tualatin basin, west of Portland (Oregon, USA), coincides with a 110 mGal gravity low along the Puget-Willamette lowland. New gravity measurements (n = 3000) reveal a three-dimensional (3-D) subsurface geometry suggesting early development as a fault-bounded pull-apart basin. A strong northwest-trending gravity gradient coincides with the Gales Creek fault, which forms the southwestern boundary of the Tualatin basin. Faults along the northeastern margin in the Portland Hills and the northeast-trending Sherwood fault along the southeastern basin margin are also associated with gravity gradients, but of smaller magnitude. The gravity low reflects the large density contrast between basin fill and the mafic crust of the Siletz terrane composing basement. Inversions of gravity data indicate that the Tualatin basin is ∼6 km deep, therefore 6 times deeper than the 1 km maximum depth of the Miocene Columba River Basalt Group (CRBG) in the basin, implying that the basin contains several kilometers of low-density pre-CRBG sediments and so formed primarily before the 15 Ma emplacement of the CRBG. The shape of the basin and the location of parallel, linear basin-bounding faults along the southwest and northeast margins suggest that the Tualatin basin originated as a pull-apart rhombochasm. Pre-CRBG extension in the Tualatin basin is consistent with an episode of late Eocene extension documented elsewhere in the Coast Ranges. The present fold and thrust geometry of the Tualatin basin, the result of Neogene compression, is superimposed on the ancestral pull-apart basin. The present 3-D basin geometry may imply stronger ground shaking along basin edges, particularly along the concealed northeast edge of the Tualatin basin beneath the greater Portland area.

  18. An integrated multiscale river basin observing system in the Heihe River Basin, northwest China

    NASA Astrophysics Data System (ADS)

    Li, X.; Liu, S.; Xiao, Q.; Ma, M.; Jin, R.; Che, T.

    2015-12-01

    Using the watershed as the unit to establish an integrated watershed observing system has been an important trend in integrated eco-hydrologic studies in the past ten years. Thus far, a relatively comprehensive watershed observing system has been established in the Heihe River Basin, northwest China. In addition, two comprehensive remote sensing hydrology experiments have been conducted sequentially in the Heihe River Basin, including the Watershed Allied Telemetry Experimental Research (WATER) (2007-2010) and the Heihe Watershed Allied Telemetry Experimental Research (HiWATER) (2012-2015). Among these two experiments, an important result of WATER has been the generation of some multi-scale, high-quality comprehensive datasets, which have greatly supported the development, improvement and validation of a series of ecological, hydrological and quantitative remote-sensing models. The goal of a breakthrough for solving the "data bottleneck" problem has been achieved. HiWATER was initiated in 2012. This project has established a world-class hydrological and meteorological observation network, a flux measurement matrix and an eco-hydrological wireless sensor network. A set of super high-resolution airborne remote-sensing data has also been obtained. In addition, there has been important progress with regard to the scaling research. Furthermore, the automatic acquisition, transmission, quality control and remote control of the observational data has been realized through the use of wireless sensor network technology. The observation and information systems have been highly integrated, which will provide a solid foundation for establishing a research platform that integrates observation, data management, model simulation, scenario analysis and decision-making support to foster 21st-century watershed science in China.

  19. Spatial and Temporal Dynamics of Potato Tuberworm in the Columbia Basin of the Pacific Northwest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A landscape-scale study from 2004-2006 investigated the spatial and temporal dynamics of a new pest to the Columbia Basin of the Pacific Northwest, the potato tuberworm, Phthorimaea operculella (Zeller). Male P. operculella were monitored in spring, summer, and fall each year with a pheromone trap...

  20. Northwest Basin and Range tectonic deformation observed with the Global Positioning System, 1999-2003

    USGS Publications Warehouse

    Hammond, W.C.; Thatcher, W.

    2005-01-01

    We use geodetic velocities obtained with the Global Positioning System (GPS) to quantify tectonic deformation of the northwest Basin and Range province of the western United States. The results are based on GPS data collected in 1999 and 2003 across five new quasi-linear networks in northern Nevada, northeast California, and southeast Oregon. The velocities show ???3 mm/yr westward movement of northern Nevada with respect to stable North America. West of longitude 119??W the velocities increase and turn northwest, parallel to Sierra Nevada/Great Valley microplate motion, and similar to velocities previously obtained to the south. The observations are explained by a kinematic model with three domains that rotate around Euler poles in eastern Oregon and western Idaho. Northeast California experiences internal dextral shear deformation (11.2 ?? 3.6 nstrain/yr) subparallel to Pacific/North America motion. Relative motions of the domains imply 2-5 mm/yr approximately east-west extension in northwest Nevada and 1-4 mm/yr approximately north-south contraction near the California/Oregon border. The northward decreasing approximately east-west extension in northwest Nevada is consistent with the northern termination of Basin and Range deformation, faulting and characteristic topography. No significant extension is detected in the Oregon Basin and Range. The Oregon Cascade arc moves north at ???3.5 mm/yr and is possibly influenced by the approximately eastward motion of the Juan de Fuca plate. These results disagree with secular northwest trenchward motion of the Oregon forearc inferred from paleomagnetic rotations. South of latitude 43??, however, trenchward motion exists and is consistent with block rotations, approximately east-west Basin and Range extension, and northwest Sierra Nevada translation. Copyright 2005 by the American Geophysical Union.

  1. Potential hazards from structural and gravitational anomalies within sedimentary basins of northwest Washington

    NASA Astrophysics Data System (ADS)

    Taylor, J. P.; Wolf, L. W.; Blakely, R. J.; Sherrod, B. L.

    2012-12-01

    This study presents preliminary models based on new and existing gravity and magnetic data for two regions in the Puget Sound, Washington, area: the Bellingham basin and the Muckleshoot basin. The principle goals of the project are to determine whether and how faults mapped outside of these basins continue beneath their thick sedimentary cover. In the Bellingham basin, cross-sectional models focus on the Drayton-Harbor magnetic lineament and the Birch Bay fault. Late Holocene displacements have been observed along these structures along the western Washington coast, and analyses of magnetic data and Lidar data suggest that these faults extend eastward into the basin. Preliminary models are consistent with the inland continuation of the Birch Bay fault towards Bellingham. The new gravity data also suggest that the Bellingham basin may consist of smaller subbasins, rather than one large basin, as previously mapped. In the Muckleshoot basin, cross-sectional models focus on the possible connection of the east-trending Tacoma fault (west of the basin) and the northwest-trending White River fault, mapped to the east of the Muckleshoot basin. A connection between these two fault systems would have significant implications for hazard estimates in terms of the length and size of these seismogenic structures.

  2. The crustal structure from the Altai Mountains to the Altyn Tagh fault, northwest China

    USGS Publications Warehouse

    Wang, Y.; Mooney, W.D.; Yuan, X.; Coleman, R.G.

    2003-01-01

    We present a new crustal section across northwest China based on a seismic refraction profile and geologic mapping. The 1100-km-long section crosses the southern margin of the Chinese Altai Mountains, Junggar Accretional Belt and eastern Junggar basin, easternmost Tianshan Mountains, and easternmost Tarim basin. The crustal velocity structure and Poisson's ratio (??), which provide a constraint on crustal composition, were determined from P and S wave data. Despite the complex geology, the crustal thickness along the entire profile is nearly uniform at 50 km. The thickest crust (56 km) occurs at the northern end of the profile beneath the Altai Mountains and the thinnest (46 km) crust is beneath the Junggar basin. Beneath surficial sediments, the crust is found to have three layers with P wave velocities (Vp) of 6.0-6.3, 6.3-6.6, and 6.9-7.0 km/s, respectively. The southern half of the profile, including the eastern Tianshan Mountains and eastern margin of the Tarim basin, shows low P wave velocities and ?? = 0.25 to a depth of 30 km, which suggests a quartz-rich, granitic upper crustal composition. The northern half of the profile below the Altai Mountains and Junggar Accretional Belt has a higher Poisson's ratio of ?? = 0.26-0.27 to a depth of 30 km, indicative of an intermediate crustal composition. The entire 1100-km-long profile is underlain by a 15-30 km thick high velocity (6.9-7.0 km/s; ?? = 0.26-0.28) lower-crustal layer that we interpret to have a bulk composition of mafic granulite. At the southern end of the profile, a 5-km-thick midcrustal low-velocity layer (Vp = 5.9 km/s, ?? = 0.25) underlies the Tianshan and the region to the south, and may be indicative of a near-horizontal detachment interface. Pn velocities are ???7.7-7.8 km/s between the Tianshan and the Junggar basin, and ???7.9-8.0 km/s below the Altai Mountains and eastern margin of the Tarim basin. We interpret the consistent three-layer stratification of the crust to indicate that the crust

  3. Transfer structures in the Northern Tarim Basin, Northwest China

    SciTech Connect

    Guang-Ya Zhang; Shi-Xia Gao

    1996-03-01

    The fold-thrust tectonics of the Northern Tarim Basin, oriented roughly parallel to the South Tianshan orogenic belt, consists of two large-scale tectonic regimes: (1) the foreland-basin, thin-skinned deformation belt; and (2) the foreland-craton, thick-skinned-dominated (i.e., basement-involved) deformation belt. Variations in the degree of deformation in these tectonic belts and style along the regional tectonic strike can be accounted for by longitudinal (progressive transfer or transverse (abrupt) transfer). Longitudinal transfer maintains the overall displacement or shortening within the fold-thrust belts as uniform or with gradual change along the tectonic strike. This includes the tectonic transfer between en echelon master thrusts and from the individual master thrust to terminal fold(s) or distributive thrusts. Transverse transfer resulted from an abrupt change in overall displacement or shortening along the tectonic strike. Within the transverse transfer zone, various tectonics-such as strike-slip faults, strike-slip thrusts, transverse anticlines, and en echelon folds-are developed. The development of longitudinal transfer zones can be attributed to the gradual variation of intrinsic and extrinsic and extrinsic deformational conditions along the tectonic strike. The initiation of transverse transfer may be related to variations in the thickness of sedimentary layers, detachment-layer distribution limits, and variation along strike of the degree and mode of the South Tianshan orogenic belt`s effect on the basin, as well as the variation of the boundary conditions of the deformation, such as in the geometry of plate margins. 15 refs., 8 figs.

  4. Thrace basin: An extensional Tertiary sedimentary basin in an area of major plate convergences, northwest Turkey

    SciTech Connect

    Turgut, S.; Atalik, E.

    1988-08-01

    The Thrace basin forms one of the largest Tertiary basins in Turkey. Paleontological and sedimentological evidence suggests sedimentation and basin formation commenced by a major transgression from the southwest in the middle to late middle Eocene. The basin formed over an extremely deformed crustal block. It straddles an Upper Cretaceous suture zone which later became a major mobile belt in Turkey. Syndepositional fault patterns and sedimentary thickness indicate the basin was evolved tectonically by north-south extension. Large listric normal faults and east-west depositional axis are evidence of this extension. Early marine sedimentation in the basin was accompanied by an intense volcanism which poured large quantities of ash into the depositional environment. Normal basement faults were active and great thicknesses of clastic sediments accumulated along faults. Reefal to shallow marine carbonates were deposited on shelves and over intrabasinal paleohighs. Sedimentation became regressive in the early Oligocene. Alternation of marine and nonmarine clastic deposition continued without interruption until the end of the Oligocene. By the late Oligocene to early Miocene, the whole basin was subjected to intense tectonism that caused uplift and faulting. Seismic reflection profiles reveal a very complex tectonic style in the basin. Fault-related inversion and flowage structures involving shale diapirism are quite common. Eocene and Oligocene shales are mature enough to generate economical quantities of hydrocarbons. Their source quality is fair to poor. Sand bodies in the Eocene-Oligocene series and reefal carbonates form the reservoir facies, and they are targets for exploration.

  5. Rejuvenation of the Kuqa foreland basin, northern flank of the Tarim basin, northwest China

    SciTech Connect

    Lu Huafu; Jia Dong; Cai Dongsheng

    1994-12-01

    The Kuqa depression along the northern flank of the Tarim basin is filled with a thick sequence of Neogene and Quaternary coarse elastic continental sediments. This structural depression is part of a large foreland basin that leads south of the Tianshan - an orogenic belt of intracontinental convergence resulting from the northward propagation of stress following the collision of India with the southern margin of Eurasia. 11 refs., 6 figs., 1 tab.

  6. Rifting to India-Asia Reactivation: Multi-phase Structural Evolution of the Barmer Basin, Rajasthan, northwest India

    NASA Astrophysics Data System (ADS)

    Kelly, M. J.; Bladon, A.; Clarke, S.; Najman, Y.; Copley, A.; Kloppenburg, A.

    2015-12-01

    The Barmer Basin, situated within the West Indian Rift System, is an intra-cratonic rift basin produced during Gondwana break-up. Despite being a prominent oil and gas province, the structural evolution and context of the rift within northwest India remains poorly understood. Substantial subsurface datasets acquired during hydrocarbon exploration provide an unrivalled tool to investigate the tectonic evolution of the Barmer Basin rift and northwest India during India-Asia collision. Here we present a structural analysis using seismic datasets to investigate Barmer Basin evolution and place findings within the context of northwest India development. Present day rift structural architectures result from superposition of two non-coaxial extensional events; an early mid-Cretaceous rift-oblique event (NW-SE), followed by a main Paleocene rifting phase (NE-SW). Three phases of fault reactivation follow rifting: A transpressive, Late Paleocene inversion along localised E-W and NNE-SSW-trending faults; a widespread Late Paleocene-Early Eocene inversion and Late Miocene-Present Day transpressive strike-slip faulting along NW-SE-trending faults and isolated inversion structures. A major Late Eocene-Miocene unconformity in the basin is also identified, approximately coeval with those identified within the Himalayan foreland basin, suggesting a common cause related to India-Asia collision, and calling into question previous explanations that are not compatible with spatial extension of the unconformity beyond the foreland basin. Although, relatively poorly age constrained, extensional and compressional events within the Barmer Basin can be correlated with regional tectonic processes including the fragmentation of Gondwana, the rapid migration of the Greater Indian continent, to subsequent collision with Asia. New insights into the Barmer Basin development have important implications not only for ongoing hydrocarbon exploration but the temporal evolution of northwest India.

  7. STP K Basin Sludge Sample Archive at the Pacific Northwest National Laboratory FY2014

    SciTech Connect

    Fiskum, Sandra K.; Smoot, Margaret R.; Schmidt, Andrew J.

    2014-06-01

    The Pacific Northwest National Laboratory (PNNL) currently houses 88 samples (~10.5 kg) of K Basin sludge (81 wet and seven dry samples) on behalf of the Sludge Treatment Project (STP), which is managed for the U.S. Department of Energy (DOE) by the CH2M Hill Plateau Remediation Company (CHPRC). Selected samples are intended to serve, in part, as sentinels to enhance understanding of sludge properties after long-term storage, and thus enhance understanding of sludge behavior following transfer to sludge transfer and storage containers (STSCs) and storage at the Hanford 200 Area central plateau. In addition, remaining samples serve in contingency for future testing requirements. At PNNL, the samples are tracked and maintained under a prescriptive and disciplined monthly sample-monitoring program implemented by PNNL staff. This report updates the status of the K Basin archive sludge sample inventory to April 2014. The previous inventory status report, PNNL 22245 (Fiskum et al. 2013, limited distribution report), was issued in February of 2013. This update incorporates changes in the inventory related to repackaging of 17 samples under test instructions 52578 TI052, K Basin Sludge Sample Repackaging for Continued Long Term Storage, and 52578 TI053, K Basin Sludge Sample Repackaging Post-2014 Shear Strength Measurements. Note that shear strength measurement results acquired in 2014 are provided separately. Specifically, this report provides the following: • a description of the K Basin sludge sample archive program and the sample inventory • a summary and images of the samples that were repackaged in April 2014 • up-to-date images and plots of the settled density and water loss from all applicable samples in the inventory • updated sample pedigree charts, which provide a roadmap of the genesis and processing history of each sample in the inventory • occurrence and deficiency reports associated with sample storage and repackaging

  8. The role of small-scale extensional faulting in the evolution of basin geometries. An example from the late Palaeozoic Petrel Sub-basin, northwest Australia

    NASA Astrophysics Data System (ADS)

    Baxter, K.

    1998-03-01

    During continental extension, the kinematic collapse of the hangingwall of major normal faults and the subsequent isostatic response imposes a strong control on the evolving basin geometry. The interaction of the flexural wavelength. and the magnitude and location of faults may allow the development of basin geometries which deviate from a classic half-graben style, particularly if some of this deformation is below the scale of observation (commonly seismic reflection data). In particular the development of a lateral partitioning between large- and small-scale faults within a basin may exert a significant control on the resulting basin geometry. Using the Petrel Sub-basin in northwest Australia as an example, it is demonstrated that an extensional basin geometry consisting of a classic half-graben can be overprinted by a significant 'sag' geometry which can be related to the lateral offset of sub-resolution faulting. This lateral partitioning and resulting basin geometry may also have an application to other extensional basins, particularly if a mechanism is present to allow this partitioning of fault styles to develop. In the Petrel Sub-basin this has been related to the presence of older basement features of the Halls Creek Mobile Zone beneath the axis of the basin. However, a comparison with physical models also suggests that this may be applicable to basins formed by oblique rifting (a component of which may also be present within the Petrel Sub-basin), particularly if this is imposed upon a weak zone or suture within the upper mantle.

  9. Effects of climate change on water resources in Tarim River Basin, Northwest China.

    PubMed

    Chen, Ya-ning; Li, Wei-hong; Xu, Chang-chun; Hao, Xin-ming

    2007-01-01

    Based on hydrology, temperature, and precipitation data from the past 50 years, the effects of climate change on water resources in Tarim River Basin in Northwest China were investigated. The long-term trends of the hydrological time series were detected using both parametric and nonparametric techniques. The results showed that the increasing tendency of the temperature has a 5% level of significance, and the temperature increased by nearly 1 degree C over the past 50 years. The precipitation showed a significant increase in the 1980s and 1990s, and the average annual precipitation exhibited an increasing trend with a magnitude of 6.8 mm per decade. A step change occurred in both the temperature and precipitation time series around 1986. The streamflow from the headwater of the Tarim River exhibited a significant increase during the last 20 years. The increase in temperature, precipitation, and streamflow may be attributed to global climate change.

  10. Recent changes in precipitation extremes in the Heihe River basin, Northwest China

    NASA Astrophysics Data System (ADS)

    Cheng, Aifang; Feng, Qi; Fu, Guobin; Zhang, Jiankai; Li, Zongxing; Hu, Meng; Wang, Gang

    2015-10-01

    Changes in rainfall extremes pose a serious and additional threat to water resources planning and management, natural and artificial oasis stability, and sustainable development in the fragile ecosystems of arid inland river basins. In this study, the trend and temporal variation of extreme precipitation are analyzed using daily precipitation datasets at 11 stations over the arid inland Heihe River basin in Northwest China from 1960 to 2011. Eight indices of extreme precipitation are studied. The results show statistically significant and large-magnitude increasing and decreasing trends for most indices, primarily in the Qilian Mountains and eastern Hexi Corridor. More frequent and intense rainfall extremes have occurred in the southern part of the desert area than in the northern portion. In general, the temporal variation in precipitation extremes has changed throughout the basin. Wet day precipitation and heavy precipitation days show statistically significant linear increasing trends and step changes in the Qilian Mountains and Hexi Corridor. Consecutive dry days have decreased obviously in the region in most years after approximately the late 1980s, but meanwhile very long dry spells have increased, especially in the Hexi Corridor. The probability density function indicates that very long wet spells have increased in the QilianMountains. The East Asian summer monsoon index and western Pacific subtropical high intensity index possess strong and significant negative and positive correlations with rainfall extremes, respectively. Changes in land surface characteristics and the increase in water vapor in the wet season have also contributed to the changes in precipitation extremes over the river basin.

  11. Hydrothermal activity in the Northwest Lau Backarc Basin: Evidence from water column measurements

    NASA Astrophysics Data System (ADS)

    Lupton, J. E.; Arculus, R. J.; Resing, J.; Massoth, G. J.; Greene, R. R.; Evans, L. J.; Buck, N.

    2012-05-01

    The Northwest Lau Backarc Basin, consisting of the Northwest Lau Spreading Center (NWLSC) and the Rochambeau Rifts (RR), is unique in having elevated 3He/4He ratios (up to 28 Ra) in the erupted lavas, clearly indicating a hot spot or ocean island basalt (OIB)-type signature. This OIB-type helium signature does not appear in any other part of the Lau Basin. Water column plume surveys conducted in 2008 and 2010 identified several sites of active hydrothermal discharge along the NWLSC-RR and showed that the incidence of hydrothermal activity is high, consistent with the high spreading rate of ˜100 mm/year. Hydrocasts into the Central Caldera and Southern Caldera of the NWLSC detected elevated3He/4He (δ3He = 55% and 100%, respectively), trace metals (TMn, TFe), and suspended particles, indicating localized hydrothermal venting at these two sites. Hydrocasts along the northern rift zone of the NWLSC also had excess δ3He, TMn, and suspended particles suggesting additional sites of hydrothermal activity. The RR are dominated by Lobster Caldera, a large volcano with four radiating rift zones. Hydrocasts into Lobster Caldera in 2008 detected high δ3He (up to 239%) and suspended particle and TMn signals, indicating active venting within the caldera. A repeat survey of Lobster in 2010 confirmed the site was still active two years later. Plumes at Lobster Caldera and Central Caldera have end-member3He/4He ratios of 19 Ra and 11 Ra, respectively, confirming that hot spot-type helium is also present in the hydrothermal fluids.

  12. Assessment of spatial and temporal patterns of green and blue water flows in inland river basins in Northwest China

    NASA Astrophysics Data System (ADS)

    Zang, C. F.; Liu, J.; van der Velde, M.; Kraxner, F.

    2012-03-01

    In arid and semi-arid regions freshwater resources have become scarcer with increasing demands from socio-economic development and population growth. Until recently, water research and management in these has mainly focused on blue water but ignored green water. Here we report on spatial and temporal patterns of both blue and green water flows simulated by the Soil and Water Assessment Tool (SWAT) for the Heihe river basin, the second largest inland river basin in Northwest China. Calibration and validation at two hydrological stations show good performance of the SWAT model in modelling hydrological processes. The total green and blue water flows were 22.09 billion m3 in the 2000s for the Heihe river basin. Blue water flows are larger in upstream sub-basins than in downstream sub-basins mainly due to high precipitation and large areas of glaciers in upstream. Green water flows are distributed more homogeneously among different sub-basins. The green water coefficient was 88.0% in the 2000s for the entire river basin, varying from around 80-90% in up- and mid-stream sub-basins to above 95% in downstream sub-basins. This is much higher than reported green water coefficient in many other river basins. The spatial patterns of green water coefficient were closely linked to dominant land covers (e.g. glaciers in upstream and desert in downstream) and climate conditions (e.g. high precipitation in upstream and low precipitation in downstream). There are no clear consistent historical trends of change in green and blue water flows and green water coefficient at both the river basin and sub-basin levels. This study provides insights into green and blue water endowments for the entire Heihe river basin at sub-basin level. The results are helpful for formulating reasonable water policies to improve water resources management in the inland river basins of China.

  13. Tectonics, basin analysis and organic geochemical attributes of Permian through Mesozoic deposits and their derivative oils of the Turpan-Hami basin, northwestern China

    NASA Astrophysics Data System (ADS)

    Greene, Todd Jeremy

    The Turpan-Hami basin is a major physiographic and geologic feature of northwest China, yet considerable uncertainty exists as to the timing of its inception, its late Paleozoic and Mesozoic tectonic history, and the relationship of its petroleum systems to those of the nearby Junggar basin. Mesozoic sedimentary fades, regional unconformities, sediment dispersal patterns, and sediment compositions within the Turpan-Hami and southern Junggar basins suggest that these basins were initially separated between Early Triassic and Early Jurassic time. Prior to separation, Upper Permian profundal lacustrine and fan-delta fades and Triassic coarse-grained braided-fluvial/alluvial fades were deposited across a contiguous Junggar-Turpan-Hami basin. Permian through Triassic fades were derived mainly from the Tian Shan to the south as indicated by northward-directed paleocurrent directions and geochemical provenance of granitoid cobbles. Lower through Middle Jurassic strata begin to reflect ponded coal-forming, lake-plain environments within the Turpan-Hami basin. A sharp change in sedimentary-lithic-rich Lower Jurassic sandstone followed by a return to lithic volcanic-rich Middle Jurassic sandstone points to the initial uplift and unroofing of the largely andesitic Bogda Shan range, which first shed its sedimentary cover as it emerged to become the partition between the Turpan-Hami and southern Junggar basins. In Turpan-Hami, source rock age is one of three major statistically significant discriminators of effective source rocks in the basin. A newly developed biomarker parameter appears to track conifer evolution and can distinguish Permian rocks and their correlative oils from Jurassic coals and mudrocks, and their derivative oils. Source fades is a second key control on petroleum occurrence and character. By erecting rock-to-oil correlation models, the biomarker parameters separate oil families into end-member groups: Group 1 oils---Lower/Middle Jurassic peatland

  14. Reservoir development in Brahaney northwest and Patricia fields, northern Midland basin, Texas

    SciTech Connect

    Mazzullo, L.J.

    1990-02-01

    Porous pay zones in the Silurian-Devonian section of the northern Midland basin, Texas, vary stratigraphically, as well as structurally, with their locations beneath the pre-Woodford unconformity. These variations are related to at least two major periods of widespread pre-Woodford tectonism and erosion. A major unconformable surface, present at the top of the Lower Silurian Fusselman formation, was later modified by tectonism and erosion immediately preceding deposition of the Woodford Shale. In places where the Fusselman subcrops beneath the Woodford, its capacity for reservoir development is dependent upon the severity of geologic events that affected the formation during the two major tectonic/erosional events. Where the Wristen and Thirtyone formations subcrop, their reservoir capacity depends upon the extent of structuring and subsequent erosion immediately prior to Woodford deposition. Two pre-Woodford oil fields in the northern Midland basin illustrate geologic complexity that bears on the successful application of subsurface mapping in defining potential pay zones. Brahaney Northwest field in Yoakum County is productive from fractured, coarse crystalline Silurian-Devonian dolomites on subtle, fault-bounded structures. These structures, defined seismically on the base of the Woodford, do not reveal the more complex structural and stratigraphic variations within the reservoir itself. Patricia field in Dawson County is productive from Fusselman carbonates where upper Fusselman structural and topographic relief coincides with post-Woodford faulting and low-relief anticlinal closure as defined at the base of the Woodford.

  15. Groundwater evolution and recharge determination of the Quaternary aquifer in the Shule River basin, Northwest China

    NASA Astrophysics Data System (ADS)

    He, Jianhua; Ma, Jinzhu; Zhao, Wei; Sun, Shuang

    2015-12-01

    Groundwater recharge and evolution in the Shule River basin, Northwest China, was investigated by a combination of hydrogeochemical tracers, stable isotopes, and radiocarbon methods. Results showed the general chemistry of the groundwater is of SO4 2- type. Water-rock reactions of halite, Glauber's salt, gypsum and celestite, and reverse ionic exchange dictated the groundwater chemistry evolution, increasing concentrations of Cl-, Na+, SO4 2-, Ca2+, Mg2+ and Sr2+ in the groundwater. The δ18O and δ2H values of groundwater ranged from -10.8 to -7.7 and -74.4 to -53.1 ‰, respectively. Modern groundwater was identified in the proluvial fan and the shallow aquifer of the fine soil plain, likely as a result of direct infiltration of rivers and irrigation returns. Deep groundwater was depleted in heavy isotopes with 14C ages ranging from 3,000 to 26,000 years, suggesting palaeowater that was recharged during the late Pleistocene and middle Holocene epochs under a cold climate. These results have important implications for groundwater management in the Shule River basin, since large amounts of groundwater are effectively being mined and a water-use strategy is urgently needed.

  16. Minimal groundwater leakage restricts salinity in a hydrologically terminal basin of northwest Australia

    NASA Astrophysics Data System (ADS)

    Skrzypek, Grzegorz; Dogramaci, Shawan; Rouillard, Alexandra; Grierson, Pauline

    2016-04-01

    The Fortescue Marsh (FM) is one of the largest wetlands of arid northwest Australia (~1200 km2) and is thought to act as a terminal basin for the Upper Fortescue River catchment. Unlike the playa lake systems that predominate in most arid regions, where salinity is driven by inflow and evaporation of groundwater, the hydrological regime of the FM is driven by inundation from irregular cyclonic events [1]. Surface water of the FM is fresh to brackish and the salinity of the deepest groundwater (80 m b.g.l.) does not exceed 160 g/L; salt efflorescences are rarely present on the surface [2]. In this study, we tested the hypothesis that persistent but low rates of groundwater outflow have restricted the accumulation of salt in the FM over time. Using hydrological, hydrochemical data and dimensionless time evaporation modelling along with the water and salt budget, we calculated the time and the annual groundwater discharge volume that would be required to achieve and maintain the range of salinity levels observed in the Marsh. Groundwater outflow from alluvial and colluvial aquifers to the Lower Fortescue catchment is limited by an extremely low hydraulic gradient of 0.001 and is restricted to a relatively small 'alluvial window' of 0.35 km2 because of the elevation of the basement bedrock at the Marsh outflow. We show that if the Marsh was 100% "leakage free" i.e., a true terminal basin for the Upper Fortescue Catchment, the basin water would have achieved salt saturation after ~45 ka. This is not the case and only a very small outflow of saline groundwater of <2 GL/yr (<0.03% of the FM water volume) is needed to maintain the current salinity conditions. The minimum time required to develop the current hydrochemical composition of the water in the Marsh and the steady-state conditions for salt concentration is between 58 and 164 ka. This is a minimum age of the Marsh but it can be much older as nearly steady-state conditions could be maintained infinitely. Our

  17. Spectral data analysis of rock and mineral in Hatu Western Junggar Region, Xinjiang

    NASA Astrophysics Data System (ADS)

    Wang, Shanshan; Zhou, Kefa; Zhang, Nannan; Wang, Jinlin

    2014-11-01

    Mineral resources are important material basis for the survival and development of human society. The development of hyperspectral remote sensing technology, which has made direct identification of minerals or mineral aggregates become possible, paves a new way for the application of remote sensing geology. The West Junggar region is located Xinjiang west verge of Junggar, with ore-forming geological conditions be richly endowed by nature and huge prospecting potentiality. The area has very good outcrop exposure with almost no vegetation cover, which is a natural test new method of remote sensing geological exploration. The characteristic of rock and mineral spectrum is not only the physical base of geological remote sensing technical application but also the base of the quantificational analysis of geological remote sensing, and the study of reflectance spectrum is the main content in the basic research of remote sensing. In this study, we collected the outdoor and indoor reflectance spectrum of rocks and minerals by using a spectroradiometer (ASD FieldSpec FR, ASD, USA), which band extent varied from 350 to 2,500 nm. Basin on a great deal of spectral data for different kinds of rocks and minerals, we have analyzed the spectrum characteristics and change of seven typical mineral rocks. According to the actual conditions, we analyzed the data noise characteristic of the spectrum and got rid of the noise. Meanwhile, continuum removed technology was used to remove the environmental background influence. Finally, in order to take full advantage of multi-spectrum data, ground information is absolutely necessary, and it is important to build a representative spectral library. We build the spectral library of rocks and minerals in Hatu, which can be used for features investigation, mineral classification, mineral mapping and geological prospecting in Hatu Western Junggar region by remote sensing. The result of this research will be significant to the research of

  18. Helium isotope variations in seafloor basalts from the Northwest Lau Backarc Basin: Mapping the influence of the Samoan hotspot

    NASA Astrophysics Data System (ADS)

    Lupton, J. E.; Arculus, R. J.; Greene, R. R.; Evans, L. J.; Goddard, C. I.

    2009-09-01

    New helium isotope results for seafloor basalts from the northern Lau Basin indicate that the signature of the Samoan hotpot has penetrated beneath the Rochambeau Rifts (RR) and the Northwest Lau Spreading Center (NWLSC) all the way to the Peggy Ridge (PR). Helium isotope ratios in 29 samples from the NWLSC - RR range from 10.9 to 28.1 Ra, all clearly higher than typical depleted mantle or MOR-type values. Comparison with other helium results from the northern Lau Basin show the Samoan hotspot influence is confined to the NWLSC - RR extensional zone, and is absent in the northeast Lau Basin and along the PR. The absence of high 3He/4He ratios in the northeast Lau Basin may delimit the eastward extent of the Pacific Plate tear which allowed southward intrusion of the Samoan plume, or indicate deep mantle flow carrying the Samoan plume signal westward from the Samoan Islands.

  19. Estimating exploration potential in mature producing area, northwest shelf of Delaware Basin, New Mexico

    SciTech Connect

    Kumar, N.

    1985-11-01

    The case history presented here describes an investigation of the Northwest shelf of the Delaware basin carried out in 1979 for estimating the potential of finding new reserves and a follow-up study to measure predictions against results. A total of 191 new-field wildcats had been drilled during 1974-1979 in the study area. An analysis of target zones and success ratios showed that the best chances of drilling a successful test were in the San Andres (Permian) and Silurian-Devonian. However, cumulative frequency plots of existing fields in these two intervals showed that the chance of finding a field larger than 1 million bbl (159,000 m/sup 3/) in either of these zones was relatively low. As a result of the 1979 analysis, three prospective areas representing 8% of the total study area were high graded, or rated as having a higher potential than other parts of the study area. The 1980-1983 drilling results show that the original high-graded areas contain 52% of the 21 successful San Andres tests and the only discovery in the Silurian-Devonian. However, as predicted by the analysis, all of these discoveries appear to be small. 12 figures, 2 tables.

  20. Fracture systems in normal fault zones crosscutting sedimentary rocks, Northwest German Basin

    NASA Astrophysics Data System (ADS)

    Reyer, Dorothea; Bauer, Johanna F.; Philipp, Sonja L.

    2012-12-01

    Field studies of fracture systems associated with 58 normal fault zones crosscutting sedimentary rocks were performed in the Northwest German Basin. Fracture orientations, densities, apertures and lengths, as well as fault zone structural indices, were analysed separately for fault damage zones and host rocks. The results show a pronounced difference between carbonate and clastic rocks: mainly in carbonate rocks we found presence of clear damage zones, characterized by higher fracture densities than in the host rocks. While the maximum aperture is similar for both units, the percentage of fractures with large apertures is much higher in the damage zones than in the host rocks. Based on laboratory measurements of Young's moduli and field measurements of fracture densities, we calculate effective stiffnesses Ee, that is the Young's moduli of the in situ rock masses, within the normal fault zones. Compared with carbonate rocks, Ee computed for clastic-rock damage zones decreases significantly less due to lower fracture densities. We conclude that normal fault zones in carbonate rocks have more profound effects on enhancing permeability in fluid reservoirs than those in clastic rocks. The results are of great importance for modelling the hydromechanical behaviour of normal fault zones in subsurface fluid reservoirs.

  1. Source identification and hazardous risk delineation of heavy metal contamination in Yanqi basin, northwest China.

    PubMed

    Mamat, Zulpiya; Yimit, Hamid; Ji, Rou Zi A; Eziz, Mamattursun

    2014-09-15

    A total of 469 surface soil samples were collected from the Yanqi basin in northwest China and evaluated for levels of ten heavy metals. Multivariate statistical analyses were used to study sources of and map the spatial distribution of heavy metals, as well as determine the relationship between land use types and soil source materials. It was found that: (1) the average amounts of ten heavy metals in the Yanqi basin were all below the national soil environmental quality standards of China (GB15618-1998), but the average amount of Cd, Hg, Mn, Ni, Pb, and Zn all exceeded the heavy metal background levels of soil in Xinjiang, China and exhibited accumulation. The ten heavy metals analyzed in this study can be categorized into four principal components as follows: Principal component 1 was Co, Cr, Mn, Ni, and Zn, and principal component 3 was As and Cu. Both of these originated from a natural geological background. Principal component 2 consisted of Cd and Pb and originated from industrial, agricultural and transportation influences. Principal component 4 consisted of Hg and was due to industrial influences. Our study found that Pb and Zn were a large part in the principal components 1 and 3 and were influenced by a combination of geologic background and human activity. (2) Heavy metals Cd and Hg were at high levels in construction land and farmland, while Co, Cr, Cu, Mn, and Ni were significantly higher in lacustrine deposits than in sandy shale from weathered material, coarse crystalline rock weathered material, and diluvial material. The land use types correlated significantly with the accumulation of Cd and Hg, and the soil parent material was the major factor for the accumulation of As, Co, Cr, Cu, Mn, and Ni. (3) The single element, element integration and the corresponding principal component presented similar spatial patterns of hazardous risk. Following comprehensive assessment of all elements, the high risk regions were found to be located in densely

  2. Late Quaternary stratigraphy, sedimentology, and geochemistry of an underfilled lake basin in the Puna (north-west Argentina)

    USGS Publications Warehouse

    McGlue, Michael M.; Cohen, Andrew S.; Ellis, Geoffrey S.; Kowler, Andrew L.

    2013-01-01

    Depositional models of ancient lakes in thin-skinned retroarc foreland basins rarely benefit from appropriate Quaternary analogues. To address this, we present new stratigraphic, sedimentological and geochemical analyses of four radiocarbon-dated sediment cores from the Pozuelos Basin (PB; northwest Argentina) that capture the evolution of this low-accommodation Puna basin over the past ca. 43 cal kyr. Strata from the PB are interpreted as accumulations of a highly variable, underfilled lake system represented by lake-plain/littoral, profundal, palustrine, saline lake and playa facies associations. The vertical stacking of facies is asymmetric, with transgressive and thin organic-rich highstand deposits underlying thicker, organic-poor regressive deposits. The major controls on depositional architecture and basin palaeogeography are tectonics and climate. Accommodation space was derived from piggyback basin-forming flexural subsidence and Miocene-Quaternary normal faulting associated with incorporation of the basin into the Andean hinterland. Sediment and water supply was modulated by variability in the South American summer monsoon, and perennial lake deposits correlate in time with several well-known late Pleistocene wet periods on the Altiplano/Puna plateau. Our results shed new light on lake expansion–contraction dynamics in the PB in particular and provide a deeper understanding of Puna basin lakes in general.

  3. Glacier retreat as a result of climate warming and increased precipitation in the Tarim river basin, northwest China

    NASA Astrophysics Data System (ADS)

    Liu, Shiyin; Ding, Yongjian; Shangguan, Donghui; Zhang, Yong; Li, Jing; Han, Haidong; Wang, Jian; Xie, Changwei

    The Tarim river basin, a river system formed by the convergence of nine tributaries, is the most heavily glacierized watershed in arid northwest China. In the basin, there are 11 665 glaciers with a total area of 19 878 km2 and a volume of 2313 km3. Glaciers in the basin play a significant role in the water resource system. It is estimated that they provide about 133 × 108 m3 of meltwater annually, contributing 39% of the total river runoff. Under the influence of global warming, northwest China has experienced a generally warmer and drier climate since the mid-19th century. However, a so-called 'warm and wet transition' has occurred since the late 1980s, evidenced by an increase in both precipitation and stream discharge in the Xinjiang Autonomous Region and neighboring regions. This paper describes how glaciers in the Tarim river basin have responded to such warming and increased precipitation, and the impact of these glacier changes. We analyzed the variations of more than 3000 glaciers since the 1960s using topographical maps, high-resolution satellite images and aerial photographs of the river basin. Our results indicate that glaciers in the basin have been mostly in retreat in the past 40 years, and ice wastage has significantly influenced water resources in the Tarim river basin. Estimation by a degree-day meltwater model shows the positive anomaly in stream runoff of the Tailan river can be partly attributed to the increase in glacier runoff (amounting to one-third of the stream discharge), and a rough estimation using observed average ablation on the termini of 15 glaciers in China verifies that the mass loss calculated by a glacier area-volume relation is reasonable.

  4. Integrated Water and Sanitation Risk Assessment and Modeling in the Upper Sonora River basin (Northwest, Mexico)

    NASA Astrophysics Data System (ADS)

    Mayer, A. S.; Robles-Morua, A.; Halvorsen, K. E.; Vivoni, E. R.; Auer, M. T.

    2011-12-01

    Studies that integrate human dimensions and the biophysical characteristics of watersheds are necessary to meet the challenge of sustainable water resources development. In this project, we integrated perspectives from sociology, hydrology, and environmental engineering to examine and suggest solutions for managing waterborne disease risks associated with wastewater contamination in the Sonora River basin (SRB), a semiarid rural basin in northwest Mexico. This research consisted of four sub-projects. First, we assessed the perceptions of risks associated with wastewater contamination of water resources in rural communities in the SRB through a series of semi-structured interviews Results from this study indicate that there are major differences in risk perceptions among health professionals, government officials, and lay citizens. Government officials and lay citizens tend to underestimate the severity of the problems related to water related risks. Second, a fully distributed hydrologic model was used to make streamflow predictions in the un-gauged SRB. Synthetic flows generated from the hydrologic model were used to evaluate pollutant transport processes associated with wastewater loadings to the Sonora River. The hydrologic model revealed that the high degree of spatio-temporal variability of runoff in the SRB is associated with links between runoff generation mechanisms and land-atmosphere interactions. Third, a surface water quality model was used to assess the impact of wastewater discharges and develop pathogen contamination indicators in two sites along the Sonora River. To parameterize the water quality model, pathogenic indicator loadings and removal rates were estimated, along with their uncertainty. Results from the water quality modeling show regions in the watershed that may be exceeding pathogenic standards, but also that uncertainty in model parameters requires a probabilistic approach for estimating risks. Finally, a workshop was conducted to

  5. Geochemical evidence for mudstone as the possible major oil source rock in the Jurassic Turpan Basin, Northwest China

    USGS Publications Warehouse

    Chen, J.; Qin, Yelun; Huff, B.G.; Wang, D.; Han, D.; Huang, D.

    2001-01-01

    Geologists and geochemists have debated whether hydrocarbons from Jurassic coal measures are derived from the mudstones or the coals themselves. This paper identifies mudstones as the possible major source rock of hydrocarbons in the Jurassic basins in Northwest China. The Turpan Basin is used as a representative model. Mudstones in the Middle-Lower Jurassic are very well developed in the basin and have an average genetic potential from 2 to 4 mg/g. The vitrinite reflectance of the source rocks ranges from 0.6 to 1.3%, exhibiting sufficient thermal maturity to generate oil and gas. Biomarkers in crude oils from the basin are similar to those in mudstones from the coal-bearing strata, with a low tricyclic terpane (cheilanthane) content, a relatively high content of low carbon number (less than C22) tricyclic terpanes and a low content of high carbon number tricyclic terpanes, relatively high ratios of Ts/Tm, and C29 Ts/17?? (H)-C29 norhopane, and low ratios of Tm/17?? (H)-C30 hopane and 17?? (H)-C31 homohopane/17?? (H)-C30 hopane. These characteristics and the distribution of steranes and terpanes in the crude oil and mudstone differ significantly from those of the Jurassic coals and carbonaceous shales of the basin, indicating mudstone is possibly the major source rock of the oils in the Turpan Basin. ?? 2001 Elsevier Science Ltd. All rights reserved.

  6. Distinct groundwater recharge sources and geochemical evolution of two adjacent sub-basins in the lower Shule River Basin, northwest China

    NASA Astrophysics Data System (ADS)

    Wang, Liheng; Dong, Yanhui; Xie, Yueqing; Song, Fan; Wei, Yaqiang; Zhang, Jiangyi

    2016-08-01

    Based on analysis of groundwater hydrogeochemical and isotopic data, this study aims to identify the recharge sources and understand geochemical evolution of groundwater along the downstream section of the Shule River, northwest China, including two sub-basins. Groundwater samples from the Tashi sub-basin show markedly depleted stable isotopes compared to those in the Guazhou sub-basin. This difference suggests that groundwater in the Tashi sub-basin mainly originates from meltwater in the Qilian Mountains, while the groundwater in the Guazhou sub-basin may be recharged by seepage of the Shule River water. During the groundwater flow process in the Tashi sub-basin, minerals within the aquifer material (e.g., halite, calcite, dolomite, gypsum) dissolve in groundwater. Mineral dissolution leads to strongly linear relationships between Na+ and Cl- and between Mg2++ Ca2+ and SO4 2- + HCO3 -, with stoichiometry ratios of approximately 1:1 in both cases. The ion-exchange reaction plays a dominant role in hydrogeochemical evolution of groundwater in the Guazhou sub-basin and causes a good linear relationship between (Mg2++ Ca2+)-(SO4 2- + HCO3 -) and (Na++ K+)-Cl- with a slope of -0.89 and also results in positive chloroalkaline indices CAI 1 and CAI 2. The scientific results have implications for groundwater management in the downstream section of Shule River. As an important irrigation district in Hexi Corridor, groundwater in the Guazhou sub-basin should be used sustainably and rationally because its recharge source is not as abundant as expected. It is recommended that the surface water should be used efficiently and routinely, while groundwater exploitation should be limited as much as possible.

  7. Vegetation and carbon sequestration and their relation to water resources in an inland river basin of Northwest China.

    PubMed

    Kang, E; Lu, L; Xu, Z

    2007-11-01

    In the Heihe River Basin in the arid inland area of northwest China, the distribution of water resources in vegetation landscape zones controls the ecosystems. The carbon sequestration capacity of vegetation is analyzed in relation to water resources and vegetation growing conditions. During the last 20 years, the vegetation ecosystems have degenerated in the Heihe River Basin. Simulation using the C-FIX model indicates that, at present, the total amount of NPP of vegetation accounts for about 18.16 TgC, and the average value is 106 gC/m(2)/yr over the whole basin. NPP has generally the highest value in the upperstream mountain area, middlestream artificial oases area, downstream river bank area, alluvial fan and the terminal lake depression where vegetation grows relatively well. The lowest value is found in the vast downstream desert and Gobi area. Protection of vegetation ecosystems and enhancement of carbon sequestration require such inland river basins as the Heihe River Basin to be brought under management in a comprehensive way, taking water as a key, to carry out a rational and efficient allocation and utilization of water resources. PMID:17126989

  8. A new frontier province offshore northwest Greenland: Structure, basin development, and petroleum potential of the Melville Bay area

    SciTech Connect

    Whittaker, R.C.; Hamann, N.E.

    1997-06-01

    In the Melville Bay area, offshore northwest Greenland, very large structures and sedimentary basins, which were predicted many years ago on the basis of magnetic and gravity data, have been confirmed by a recent reconnaissance seismic survey, with implications that are encouraging for petroleum exploration in the area. The Melville Bay area flanks a small ocean basin in Baffin Bay that is thought to have formed by oblique sea-floor spreading in the Eocene. There are two major, coast-parallel basins in the area. The inner basin, the Melville Bay Graben, is essentially a half graben with a maximum thickness of sediments exceeding 13 km. A complex fault-controlled ridge system separates this basin from the outer Kivioq Basin in which up to 7 km of sediments have accumulated. By analogy with onshore geology in the surrounding areas and well data from the continental shelves off southern west Greenland and Labrador to the south, it is expected that the first phase of rifting and sedimentation took place in the Early-middle Cretaceous, while a second phase of rifting took place in the latest Cretaceous and early Paleocene. Later, compression and inversion affected the northern part of the area, leading to the formation of large anticlinal structures. The existence of large tilted fault blocks and inversion anticlines provides grounds for anticipating the presence of large structural traps. Synrift sandstones and deeper water fans are expected to provide potential reservoirs, and correlatives of oil-prone source rocks known from the lower part of the upper Cenomanian-lower Maastrichtian Kanguk Formation in the Canadian Arctic may also have oil source properties in the Melville Bay area. Recent discoveries of live oil in the uppermost Cretaceous and lower Tertiary of onshore central west Greenland provide proof that oil has been generated in the region.

  9. Basement and Basin Structures of the Northwest Paraná Basin, Brazil: Illuminated by Matched-Filter Analysis and 2D Modeling of Gravity and Magnetic Data

    NASA Astrophysics Data System (ADS)

    Curto, J. B.; Blakely, R. J.; Vidotti, R. M.; Fuck, R. A.

    2015-12-01

    The South American Platform includes two major geological components with common structural roots: the Transbrasiliano Lineament (LTB) and the Paraná Basin. Important relationships between the two components occur within the northwest Paraná Basin and concealed beneath sedimentary cover. We integrated all available airborne magnetic and gravity surveys and ground-based gravity data to produce consistent, digital magnetic and Bouguer anomaly maps. Data-processing and modeling techniques then were used in order to reveal principal crustal compartments and basin-basement structures at various depths. Three large magnetic discontinuities delineate crustal compartments in the area with N30°E, N60°E, and N70°E strike, from east to west, respectively. These magnetic lineaments bound regions with distinct gravity anomaly character. Robust matched-filter analysis applied to magnetic and gravity data yielded important depth estimates: (i) 2.5 km to the top of the Paraná Basin Neoproterozoic basement; (ii) 4-6 km to the top of a second group of basement units; (iii) 20 km, possibly associated with the upper-lower crust interface; and (iv) 33-39 and 43 km related to crustal thicknesses west and southeast of a major N30°E trending lineament, respectively. The 2D joint modeling of gravity and magnetic data sheds light on the asymmetric geometry of the basement beneath the Paraná basin, with at least three half-grabens formed by LTB reactivated structures. The central region of the study area is characterized by thinner crust and higher crustal weakness, where important structures have developed in the Mesozoic, including NW trending reactivations, linked to crustal uplift and evolution of small NE-aligned Cretaceous basins. Important depocenters occur to the north and east of the study area, with N70ºE and N30°E - NS strike, respectively.

  10. Tectonic evolution of the East Junggar terrane, CAOB

    NASA Astrophysics Data System (ADS)

    Xu, Xing-Wang

    2016-04-01

    The East Junggar terrane is one of the important tectonic units of the Central Asian Orogenic Belt (CAOB; Zonenshain et al., 1990). Debate surrounds the tectonics of the East Junggar area, including tectonic setting, age, basement nature, subduction polarity and collisional time between the East Junggar terrane and Junggar block (e.g., Xiao et al., 2008, 2011; Long et al., 2012; Huang et al., 2012). Among the two popular models, one suggests that the Junggar is a continental block (e.g. Zhang et al., 1984, 1993; Watson et al., 1987; Xiao et al., 1992; He et al., 1994; Li et al., 2000; Charvet et al., 2001, 2007; Xu et al., 2003; Zhao et al., 2003; Buslov et al., 2004; Xu and Ma, 2004; Dong et al., 2009; Bazhenov et al., 2012; Choulet et al., 2012; Zhang et al., 2012). The other model proposes that the Junggar has a basement of Paleozoic oceanic crust (e.g., Carroll et al., 1990; Zheng et al., 2007) or oceanic island arc complexes (e.g., Coleman, 1989; Chen and Jahn, 2004; Windley et al., 2007) of the Altaid Paleozoic rocks (e.g., Sengör et al., 1993; Sengör and Natal'in, 1996; Allen and Vincent, 1997; Filippova et al., 2001; Xiao et al., 2004a, 2004b, 2008, 2009, 2010a, 2010b, 2012). The tectonics in the Eastern Junggar area are interpreted to be related to late Paleozoic intra-oceanic accretion induced by northward subduction of the Junggar oceanic lithosphere (e.g. Xiao et al., 2008, 2009; Biske and Seltmann, 2010; Wan et al., 2011; Yang et al., 2011) or by the southward subduction of the Paleo-Asian oceanic lithosphere (Zhang et al., 2004; Wong et al., 2010; Su et al., 2012). Recently, we did detailed field survey and petrological, geochemical and chronological analysis of the metamorphosed volcanic rocks and magmatic rocks, and new discovered gneiss and magnetite quartzite enclaves from the Taheir tectonic window in the East Junggar region which is situated between the Zaisan-Erqis-the Main Mongolian Lineament-suture and the Kelameili suture. The new results

  11. An integrated workflow to assess the remaining potential of mature hydrocarbon basins: a case study from Northwest Germany (Upper Jurassic/Lower Cretaceous, Lower Saxony Basin)

    NASA Astrophysics Data System (ADS)

    Seyfang, Björn; Aigner, Thomas; Munsterman, Dirk K.; Irmen, Anton

    2016-06-01

    Mature hydrocarbon provinces require a high level of geological understanding in order to extend the lives of producing fields, to replace reserves through smaller targets and to reduce the risks of exploring for more and more subtle hydrocarbon traps. Despite a large number of existing wells in the area studied in this paper, the depositional environments and the stratigraphic architecture were still poorly known. In order to improve the geological understanding, we propose a workflow to assess the remaining reservoir potential of mature hydrocarbon areas, integrating cores, cuttings, well-logs, biostratigraphy and seismic data. This workflow was developed for and is exemplified with the northwest of the Lower Saxony Basin (LSB), a mature hydrocarbon province in northwest Germany, but can be applied in a similar fashion to other areas. Systematic integration of lithofacies analysis, chrono- and sequence stratigraphy, combined with electrofacies analysis and modern digital methods like neural network-based lithology determination and 3D facies modelling provides a high-resolution understanding of the spatial facies and reservoir architecture in the study area. Despite widely correlatable litho-units in the Upper Jurassic and Lower Cretaceous in the LSB, complex heterogeneous sedimentary systems can be found in the basin's marginal parts. Two new play types were determined in the study area, showing a remaining potential for stratigraphic hydrocarbon traps. The results of this exploration scale study also provide the basis for re-evaluations on a field development scale. On a basin scale, this study may encourage further data acquisition and re-evaluations to discover previously unknown reservoirs.

  12. The potential for coalbed gas exploration and production in the Greater Green River Basin, southwest Wyoming and northwest Colorado

    SciTech Connect

    Tyler, R.; Kaiser, W.R.; Scott, A.R.; Hamilton, D.S.

    1997-01-01

    Coalbed gas is an important source of natural gas in the United States. In 1993, approximately 740 BCF of coalbed gas was produced in the United States, or about 4.2% of the nation`s total gas production. Nearly 96% of this coalbed gas is produced from just two basins, the San Juan (615.7 BCF; gas in place 84 TCF) and Black Warrior (105 BCF; gas in place 20 TCF), and current production represents only a fraction of the nation`s estimated 675 TCF of in-place coalbed gas. Coal beds in the Greater Green River Basin in southwest Wyoming and northwest Colorado hold almost half of the gas in place (314 TCF) and are an important source of gas for low-permeability Almond sandstones. Because total gas in place in the Greater Green River Basin is reported to exceed 3,000 TCF (Law et al., 1989), the basin may substantially increase the domestic gas resource base. Therefore, through integrated geologic and hydrologic studies, the coalbed gas potential of the basin was assessed where tectonic, structural, and depositional setting, coal distribution and rank, gas content, coal permeability, and ground-water flow are critical controls on coalbed gas producibility. Synergism between these geologic and hydrologic controls determines gas productivity. High productivity is governed by (1) thick, laterally continuous coals of high thermal maturity, (2) basinward flow of ground water through fractured and permeable coals, down the coal rank gradient toward no-flow boundaries oriented perpendicular to the regional flow direction, and (3) conventional trapping of gas along those boundaries to provide additional sources of gas beyond that sorbed on the coal surface.

  13. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    PubMed

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014) and near future (2015-2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses. PMID:27348224

  14. Basin development and compressional deformation in the central High Atlas Mountains northwest of Errachidia (Morocco) - rejuvenated tectonics

    SciTech Connect

    Brede, R.

    1988-08-01

    The development of the central High Atlas Mountains from the Triassic until today was controlled by a set of pre-existent basement faults which were reactivated in various manners. During the Triassic a graben began to subside at the northwestern border of the African craton. The graben's development was at least temporarily linked to the opening of the Atlantic Ocean. The growing basin was filled by red detrital material from the adjacent elevated regions. Evaporites were only locally formed. Mostly the red beds show an intercalation of basic volcanics. During the early and middle Liassic, a shallow shelf with reefs existed at the southern rim of the Atlas-Gulf, from which much carbonate material was delivered into the basin. This deposition is proved by turbiditic limestones of considerable thickness in the Pliensbachian. After a further deepening of the Atlas-Gulf in the late Liassic and the early Dogger, a trend toward shallowing began in the Bajocian, enabling reefs to grow from the south into the basin. Toward the end of the middle Dogger, the trough began to fill with red detrital material. This period of red-bed sedimentation lasted until the early part of the late Cretaceous and had abundant intercalation of gypsum near the top of the sequence. Due to a transgression a short marine period followed, documented by the Cenomanian-Turonian limestones. This marine period was succeeded again by the deposition of red beds in the middle of late Cretaceous. The Jurassic sediments are sometimes penetrated by small doleritic dikes. The development of the basin was controlled by east-northeast-striking faults. During compression in the Tertiary, the /sigma//sub 3/ direction (north-northwest) of the Mesozoic basin development changed into the /sigma//sub 1/ direction of compressional deformation and the synsedimentary normal faults were reactivated as upthrusts.

  15. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China

    PubMed Central

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995–2014) and near future (2015–2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses. PMID:27348224

  16. Hydrological Impacts of Land Use Change and Climate Variability in the Headwater Region of the Heihe River Basin, Northwest China.

    PubMed

    Zhang, Ling; Nan, Zhuotong; Xu, Yi; Li, Shuo

    2016-01-01

    Land use change and climate variability are two key factors impacting watershed hydrology, which is strongly related to the availability of water resources and the sustainability of local ecosystems. This study assessed separate and combined hydrological impacts of land use change and climate variability in the headwater region of a typical arid inland river basin, known as the Heihe River Basin, northwest China, in the recent past (1995-2014) and near future (2015-2024), by combining two land use models (i.e., Markov chain model and Dyna-CLUE) with a hydrological model (i.e., SWAT). The potential impacts in the near future were explored using projected land use patterns and hypothetical climate scenarios established on the basis of analyzing long-term climatic observations. Land use changes in the recent past are dominated by the expansion of grassland and a decrease in farmland; meanwhile the climate develops with a wetting and warming trend. Land use changes in this period induce slight reductions in surface runoff, groundwater discharge and streamflow whereas climate changes produce pronounced increases in them. The joint hydrological impacts are similar to those solely induced by climate changes. Spatially, both the effects of land use change and climate variability vary with the sub-basin. The influences of land use changes are more identifiable in some sub-basins, compared with the basin-wide impacts. In the near future, climate changes tend to affect the hydrological regimes much more prominently than land use changes, leading to significant increases in all hydrological components. Nevertheless, the role of land use change should not be overlooked, especially if the climate becomes drier in the future, as in this case it may magnify the hydrological responses.

  17. A 150 year precipitation record preserved in lake sediments of Lake Gahai in the Qaidam Basin, northwest China

    NASA Astrophysics Data System (ADS)

    Li, X.

    2012-12-01

    A 150 year precipitation record preserved in lake sediments of Lake Gahai in the Qaidam Basin, northwest China Li Xiangzhong a, Liu Weiguoa, b a State Key Laboratory of Loess and Quaternary Geology, IEE, CAS, Xi'an, 710075, China b School of Human Settlement and Civil Engineering, Xi'an Jiaotong University, Xi'an, 710049, China Abstract Usually, the oxygen isotopic compositions of ostracods from the lake sediments are interpreted as changes in effective precipitation, temperature and evaporation/input water ratio in a sub-arid or arid area. Here, we compare a 150-year-long oxygen-isotope record that was derived from ostracod carbonate from the sediment core (in a seven-year resolution) of Lake Gahai in the Qaidam Basin with meteorological data (precipitation) and tree-ring evidence for changing precipitation. Our results show that the increased precipitation accompanied a shift to less positive δ18O values in the lake water, and hence of the ostracod shells, whereas decreased precipitation coincides with the opposite in Lake Gahai over the past ~150 years. The sole occurrence of the ostracod E. mareotica also indicates that the lake's salinity may have experienced no marked change over the past 150 years. Therefore, we conclude that the oxygen isotopic compositions of ostracod shells can be used to indicate changes in precipitation for paleoclimatic reconstruction over a short time scale in Lake Gahai. Keywords: oxygen isotope; ostracod; precipitation; Lake Gahai, Qaidam Basin

  18. Farmers' attitudes toward mandatory water-saving policies: A case study in two basins in northwest China.

    PubMed

    Chang, Genying; Wang, Lu; Meng, Liuyi; Zhang, Wenxia

    2016-10-01

    China began to implement stringent water-saving policies in 2012. Mandatory water-saving measures implemented in arid inland river basins include the measures of allocating surface water among upper, middle and lower beaches, restricting household agricultural water use, closing wells, reducing farmland and increasing water prices. These measures have negative influences on the agricultural production of farmers. This study aimed to reveal the demographic and psychological correlates of farmers' attitudes toward these policies. The participants included 672 farmers in the Heihe River Basin and the Shule River Basin in northwest China. Structural equation analyses showed that farmers' awareness of the beneficial consequences of restricting household agricultural water and their perception of policy enforcement had significant relationships with their attitudes toward water-saving policies, whereas the effects of the New Ecological Paradigm and collectivism on farmers' attitudes were mediated through their awareness of beneficial consequences and their perception of policy enforcement. Multivariable regression analyses revealed that as a whole, there were no significant correlations between demographic variables and farmers' attitudes. Policy implications include propagandizing these policies among local farmers, strengthening open and fair policy enforcement, and cautiously using water prices as an instrument to control irrigation water. PMID:27420168

  19. Air Pollution Over the Ganges Basin and Northwest Bay of Bengal in the Early Postmonsoon Season Based on NASA MERRAero Data

    NASA Technical Reports Server (NTRS)

    Kishcha, Pavel; Da Silva, Arlindo M.; Starobinets, Boris; Alpert, Pinhas

    2014-01-01

    The MERRA Aerosol Reanalysis (MERRAero) has been recently developed at NASA's Global Modeling Assimilation Office. This reanalysis is based on a version of the Goddard Earth Observing System-5 (GEOS-5) model radiatively coupled with Goddard Chemistry, Aerosol, Radiation, and Transport aerosols, and it includes assimilation of bias-corrected aerosol optical thickness (AOT) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on both Terra and Aqua satellites. In October over the period 2002-2009, MERRAero showed that AOT was lower over the east of the Ganges basin than over the northwest of the Ganges basin: this was despite the fact that the east of the Ganges basin should have produced higher anthropogenic aerosol emissions because of higher population density, increased industrial output, and transportation. This is evidence that higher aerosol emissions do not always correspond to higher AOT over the areas where the effects of meteorological factors on AOT dominate those of aerosol emissions. MODIS AOT assimilation was essential for correcting modeled AOT mainly over the northwest of the Ganges basin, where AOT increments were maximal. Over the east of the Ganges basin and northwest Bay of Bengal (BoB), AOT increments were low and MODIS AOT assimilation did not contribute significantly to modeled AOT. Our analysis showed that increasing AOT trends over northwest BoB (exceeding those over the east of the Ganges basin) were reproduced by GEOS-5, not because of MODIS AOT assimilation butmainly because of the model capability of reproducing meteorological factors contributing to AOT trends. Moreover, vertically integrated aerosol mass flux was sensitive to wind convergence causing aerosol accumulation over northwest BoB.

  20. Geologic Mapping Investigations of the Northwest Rim of Hellas Basin, Mars

    NASA Technical Reports Server (NTRS)

    Crown, David A.; Bleamaster, Leslie F., III; Mest, Scott C.; Mustard, John F.

    2009-01-01

    The Hellas impact basin, spanning 2000+ km in the cratered highlands, is the largest well-preserved impact structure on Mars and its deepest depositional sink. The Hellas region is significant for evaluating Mars hydrogeologic and climate histories, given the nature, diversity, and range in ages of potential water- and ice-related landforms [e.g., 1-2], including possible paleolakes on the basin floor [2-4]. The circum-Hellas highlands are of special interest given recent studies of potential localized fluvial/lacustrine systems [2, 5-17] and evidence for phyllosilicates around and within impact craters north of the basin [18-26].

  1. Estimation of subsurface formation temperature in the Tarim Basin, northwest China: implications for hydrocarbon generation and preservation

    NASA Astrophysics Data System (ADS)

    Liu, Shaowen; Lei, Xiao; Feng, Changge; Hao, Chunyan

    2016-07-01

    Subsurface formation temperature in the Tarim Basin, northwest China, is vital for assessment of hydrocarbon generation and preservation, and of geothermal energy potential. However, it has not previously been well understood, due to poor data coverage and a lack of highly accurate temperature data. Here, we combined recently acquired steady-state temperature logging data with drill stem test temperature data and measured rock thermal properties, to investigate the geothermal regime and estimate the subsurface formation temperature at depth in the range of 1000-5000 m, together with temperatures at the lower boundary of each of four major Lower Paleozoic marine source rocks buried in this basin. Results show that heat flow of the Tarim Basin ranges between 26.2 and 66.1 mW/m2, with a mean of 42.5 ± 7.6 mW/m2; the geothermal gradient at depth of 3000 m varies from 14.9 to 30.2 °C/km, with a mean of 20.7 ± 2.9 °C/km. Formation temperature estimated at the depth of 1000 m is between 29 and 41 °C, with a mean of 35 °C, while 63-100 °C is for the temperature at the depth of 3000 m with a mean of 82 °C. Temperature at 5000 m ranges from 97 to 160 °C, with a mean of 129 °C. Generally spatial patterns of the subsurface formation temperature at depth are basically similar, characterized by higher temperatures in the uplift areas and lower temperatures in the sags, which indicates the influence of basement structure and lateral variations in thermal properties on the geotemperature field. Using temperature to identify the oil window in the source rocks, most of the uplifted areas in the basin are under favorable condition for oil generation and/or preservation, whereas the sags with thick sediments are favorable for gas generation and/or preservation. We conclude that relatively low present-day geothermal regime and large burial depth of the source rocks in the Tarim Basin are favorable for hydrocarbon generation and preservation. In addition, it is found that the

  2. Quaternary glacial, lacustrine, and fluvial interactions in the western Noatak basin, Northwest Alaska

    USGS Publications Warehouse

    Hamilton, T.D.

    2001-01-01

    The 130 km long Noatak basin is surrounded by mountains of the western Brooks Range. Middle and late Pleistocene glaciers flowing southeast into the basin dammed a succession of proglacial lakes defined by shorelines, outlet channels and upper limits of wave erosion. More than 60 bluffs along the Noatak River and its principal tributaries expose glacial and glaciolacustrine sediments that exhibit cut-and-fill relationships with interglacial and interstadial river-channel and floodplain deposits. This report focuses on the western Noatak basin, where high bluffs created by deep postglacial erosion record four major glacial advances. During the Cutler advance, a floating ice tongue terminated in a large proglacial lake that filled the Noatak basin. The retreating glacier abandoned a trough along the valley center that subsequently filled with about 40m of sediment during several younger glaciations and probably two major interglacial episodes. Alluvium that formed near the beginning of the younger interglaciation contains the 140,000 yr old Old Crow tephra. The subsequent closely spaced Okak and Makpik advances are clearly younger than the maximum of the last interglaciation, but they preceded a middle Wisconsin (36-30 ka) nonglacial interval in the Noatak basin. The Okak advance terminated in an extensive lake, whereas glaciers of the Makpik and the subsequent Anisak advances flowed into much narrower lakes that filled only the basin center. The Anisak advance, bracketed by radiocarbon ages of about 35 and 13.6 ka, represents the Last Glacial Maximum (LGM) in the western Noatak basin. Correlations with the oldest and youngest glacial deposits of the central Brooks Range are clear, but relationships to events of intermediate age are more tenuous. Early Pleistocene and older glacial advances from the central Brooks Range must have filled the Noatak basin and overflowed northward through Howard Pass. A younger glacial advance, of inferred middle Pleistoscene

  3. The Federal Cylinder Project: A Guide to Field Cylinder Collections in Federal Agencies. Volume 3, Great Basin/Plateau Indian Catalog, Northwest Coast/Arctic Indian Catalog.

    ERIC Educational Resources Information Center

    Gray, Judith A., Ed.

    Two catalogs inventory wax cylinder collections, field recorded among Native American groups, 1890-1942. The catalog for Great Basin and Plateau Indian tribes contains entries for 174 cylinders in 7 collections from the Flathead, Nez Perce, Thompson/Okanagon, Northern Ute, and Yakima tribes. The catalog for Northwest Coast and Arctic Indian tribes…

  4. Assessing the changes in land use and ecosystem services in an oasis agricultural region of Yanqi Basin, Northwest China.

    PubMed

    Wang, Shuixian; Wu, Bin; Yang, Pengnian

    2014-12-01

    The Yanqi Basin, one of the most productive agricultural areas, has a high population density in Xinjiang, Northwest China. Land use changes, mainly driven by oasis expansion, significantly impact ecosystem services and functions, but these effects are difficult to quantify. The valuation of ecosystem services is important to clarify the ecological and environmental changes caused by agriculturalization of oasis. This study aimed to investigate variations in ecosystem services in response to land use changes during oasis agricultural expansion activities in the Yanqi Basin from 1964 to 2009. The methods used were based on formula of ecosystem service value (ESV) and ESV coefficients. Satellite data were combined with the ESV coefficients to quantify land use changes and ecosystem service changes in the study area. Sensitivity analysis determined the effect of manipulating the coefficients on the estimated values. The results show that the total ESVs in the Yanqi Basin were $1,674, $1,692, $1,471, $1,732, and $1,603 million in 1964, 1973, 1989, 1999, and 2009, respectively. The net deline in ESV was $71 million in the past 46 years, but the ESVs of each types of landscape changed significantly. The aggregated ESVs of water areas and wetlands were approximately 80 % of the total ESV. Water supply and waste treatment were the two largest service functions and contributed approximately 65 % of the total ESV. The estimated ESVs in this study were elastic with respect to the value coefficients. Therefore, the estimations were robust in spite of uncertainties on the value coefficients. These significant changes in land use occur within the entire basin over the study period. These changes cause environmental problems, such as land degradation, vegetation degeneracy, and changes in aquatic environment.

  5. Achieving Sustainability in a Semi-Arid Basin in Northwest Mexico through an Integrated Hydrologic-Economic-Institutional Model

    NASA Astrophysics Data System (ADS)

    Munoz-Hernandez, A.; Mayer, A. S.

    2008-12-01

    The hydrologic systems in Northwest Mexico are at risk of over exploitation due to poor management of the water resources and adverse climatic conditions. The purpose of this work is to create and Integrated Hydrologic-Economic-Institutional Model to support future development in the Yaqui River basin, well known by its agricultural productivity, by directing the water management practices toward sustainability. The Yaqui River basin is a semi-arid basin with an area of 72,000 square kilometers and an average precipitation of 527 mm per year. The primary user of water is agriculture followed by domestic use and industry. The water to meet user demands comes from three reservoirs constructed, in series, along the river. The main objective of the integrated simulation-optimization model is to maximize the economic benefit within the basin, subject to physical and environmental constraints. Decision variables include the water allocation to major users and reservoirs as well as aquifer releases. Economic and hydrologic (including the interaction of the surface water and groundwater) simulation models were both included in the integrated model. The surface water model refers to a rainfall-runoff model created, calibrated, and incorporated into a MATLAB code that estimates the monthly storage in the main reservoirs by solving a water balance. The rainfall-runoff model was coupled with a groundwater model of the Yaqui Valley which was previously developed (Addams, 2004). This model includes flow in the main canals and infiltration to the aquifer. The economic benefit of water for some activities such as agricultural use, domestic use, hydropower generation, and environmental value was determined. Sensitivity analysis was explored for those parameters that are not certain such as price elasticities or population growth. Different water allocation schemes were created based on climate change, climate variability, and socio-economic scenarios. Addams L. 2004. Water resource

  6. The occurrence, sources and spatial characteristics of soil salt and assessment of soil salinization risk in Yanqi basin, northwest China.

    PubMed

    Zhaoyong, Zhang; Abuduwaili, Jilili; Yimit, Hamid

    2014-01-01

    In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1) In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2) The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3) Principle component (PC) analysis determined that all the salt ion values, potential of hydrogen (pHs) and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO4(2-), EC, and pH) and PC2 (Ca2+, K+, Mg2+and total amount of salts) are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3(-) and HCO3(2-)) are mainly influenced by natural sources. (4) From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3(-), had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5) Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world.

  7. The occurrence, sources and spatial characteristics of soil salt and assessment of soil salinization risk in Yanqi basin, northwest China.

    PubMed

    Zhaoyong, Zhang; Abuduwaili, Jilili; Yimit, Hamid

    2014-01-01

    In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1) In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2) The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3) Principle component (PC) analysis determined that all the salt ion values, potential of hydrogen (pHs) and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO4(2-), EC, and pH) and PC2 (Ca2+, K+, Mg2+and total amount of salts) are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3(-) and HCO3(2-)) are mainly influenced by natural sources. (4) From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3(-), had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5) Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world. PMID:25211240

  8. The Occurrence, Sources and Spatial Characteristics of Soil Salt and Assessment of Soil Salinization Risk in Yanqi Basin, Northwest China

    PubMed Central

    Zhaoyong, Zhang; Abuduwaili, Jilili; Yimit, Hamid

    2014-01-01

    In order to evaluate the soil salinization risk of the oases in arid land of northwest China, we chose a typical oasis-the Yanqi basin as the research area. Then, we collected soil samples from the area and made comprehensive assessment for soil salinization risk in this area. The result showed that: (1) In all soil samples, high variation was found for the amount of Ca2+ and K+, while the other soil salt properties had moderate levels of variation. (2) The land use types and the soil parent material had a significant influence on the amount of salt ions within the soil. (3) Principle component (PC) analysis determined that all the salt ion values, potential of hydrogen (pHs) and ECs fell into four PCs. Among them, PC1 (C1-, Na+, SO42-, EC, and pH) and PC2 (Ca2+, K+, Mg2+and total amount of salts) are considered to be mainly influenced by artificial sources, while PC3 and PC4 (CO3- and HCO32-) are mainly influenced by natural sources. (4) From a geo-statistical point of view, it was ascertained that the pH and soil salt ions, such as Ca2+, Mg2+ and HCO3-, had a strong spatial dependency. Meanwhile, Na+ and Cl- had only a weak spatial dependency in the soil. (5) Soil salinization indicators suggested that the entire area had a low risk of soil salinization, where the risk was mainly due to anthropogenic activities and climate variation. This study can be considered an early warning of soil salinization and alkalization in the Yanqi basin. It can also provide a reference for environmental protection policies and rational utilization of land resources in the arid region of Xinjiang, northwest China, as well as for other oases of arid regions in the world. PMID:25211240

  9. Heat flow, deep formation temperature and thermal structure of the Tarim Basin, northwest China

    NASA Astrophysics Data System (ADS)

    Liu, Shaowen; Lei, Xiao; Feng, Changge; Li, Xianglan

    2016-04-01

    Geothermal regime of a sedimentary basin not only provides constraint on understanding the basin formation and evolution, but also offers fundamental parameters for hydrocarbon resources assessment. As one of three Precambrian blocks in China, the Tarim craton is also a current hydrocarbon exploration target where the largest sedimentary basin (Tarim Basin) develops with great potential. Although considerable advancement of geothermal regime of this basin has been made during the past decades, nearly all the temperature data in previous studies are from the exploration borehole formation testing temperatures. Recently, we have conducted the steady-state temperature logging in the Tarim basin, and measured abundant rock thermal properties, enabling us to re-visit the thermal regime of this area with more confidence. Our results show that the present-day geothermal gradients for the Tarim Basin vary from 23 K/km to 27 K/km, with a mean of 22 K/km; the values of heat flow range from 40 mW/m2 to 49 mW/m2, with a mean of 43 mW/m2. These new data confirmed that the Tarim Basin has relatively low heat flow and shares similar geothermal regime with other Precambrian cratons in the world. In addition, the new temperatures from the steady-state logs are larger than the bottom hole temperatures (BHT) as 22 degree Celsius, indicating the thermal non-equilibrium for the BHTs used in previous studies. Spatial distribution of the estimated formation temperatures-at-depth of 1~5km within the basin is similar and mainly controlled by crystalline basement pattern. Generally, the temperatures at the depth of 1km range from 29 to 41 degree Celsius, with a mean of 35 degree Celsius; while the temperatures at 3km vary from 63 to 100 degree Celsius, and the mean is 82 degree Celsius; at 5km below the surface, the temperatures fall into a range between 90 and 160 degree Celsius, with a mean of 129 degree Celsius. We further proposed the long-term low geothermal background and large burial

  10. Detailed sedimentological study in deltaic upper sequence of the Thrace Basin, northwest Turkey

    SciTech Connect

    Aksoy, M.Z. )

    1990-05-01

    The Thrace basin forms one of the largest Tertiary sedimentary basins in Turkey. Paleontological and sedimentological evidence suggests that sedimentation and basin formation commenced by a major transgression from the southwest in the middle to late middle Eocene. Sedimentological studies indicate that two major depositional cycles prevailed during the formation of the Thrace basin. The lower sequence of sediments (first cycle) was deposited in deep marine environments by turbidity currents as submarine fans (approximately 3,500 m thick). The upper sequence of sediments (second cycle) was deposited in various subenvironments, of which deltaic depositional conditions were the most prominent and 2,600 m thick sediments were deposited. The total sedimentary thickness (6,100 m), deposited until the end of the Oligocene, indicates that rates of subsidence and deposition were quite high. Deltaic deposition started in the beginning of the Oligocene when the rate of subsidence slowed. At this time, the Thrace basin was relatively filled to its maximum capacity and shallow-marine conditions became prevalent. It is seen that initially the rate of sedimentation was higher than the rate of subsidence. Sedimentation in the basin continued from the beginning of the middle Eocene to the end of the Oligocene, with no break in sedimentation. The depositional environment changed from deep marine fan deposits to deltas. Geometry and sand-body thickness along with the sand/shale ratio throughout the delta sequence have been determined using data obtained from 29 wells. Based on this study, deltaic sand bodies in the Thrace basin are now among the major hydrocarbon exploration targets.

  11. Oblique-slip sedimentation and deformation in Nonacho basin (early Proterozoic), Northwest Territories, Canada

    SciTech Connect

    Aspler, L.B.; Donaldson, J.A.

    1984-04-01

    The Nonacho basin shares several traits with molassoid basins formed in oblique-slip settings: great thickness (about 9 km, 6 mi) of siliciclastic sediments deposited in alluvial fan, fan-delta, braided stream, beach, deltaic, and lacustrine environments; synsedimentary faults which activated nearby sources; rapid sedimentation and subsidence; telescoped facies transitions, particularly adjacent to active faults; extremely variable thickness of lithostratigraphic units; diachronous sedimentation resulting from the migration of source areas and sites of sedimentation along deformation fronts; mobility of deposition and deformation such that early sediments were uplifted, cannibalized, and redeposited; paleocurrents directed basinward near basin margins, and longitudinally in axial regions; lower greenschist facies metamorphism; paucity of volcanic rocks; and complicated structural geometries. However, these features alone are not diagnostic of qbique slip origin; all are compatible with rift, aulacogen, impactogen, retroarc, peripheral, intramontane, and broken foreland settings. More reliable indicators or an oblique-slip tectonic setting for the Nonacho basin are: anastomosing pattern of near-vertical, en echelon faults which delineate rhomb-, wedge, and rectangular-shaped semi-independent subbasins and basement uplifts; stretching lineations of shallow to moderate plunge along shear zones; folds and near-vertical penetrative fabrics, related to shear zones, but at angles of 20/sup 0/-30/sup 0/ to these zones. The Nonacho basin fill is interpreted as a foreland molasse of the Trans-Hudson orogene. Deposition and deformation probably occurred in response to convergence accommodated by oblique slip, analogous to the Tarim and Tsaidam basins of China, which developed in the late stages of India-Eurasia collision, north of the Tibetan Plateau.

  12. Testing the Origins of Nonmarine Stratigraphic Sequences, Iglesia Basin, Northwest Argentina

    NASA Astrophysics Data System (ADS)

    Ruskin, B. G.; Jordan, T.

    2003-12-01

    The Iglesia Basin is an entirely nonmarine Andean foreland basin consisting of approximately 3.5 km of Tertiary strata unconformably overlying Paleozoic basement. Best described as a wedge-top basin, Iglesia Basin is located in San Juan Province, Argentina at S 30-31\\deg between the Frontal Cordillera and Precordillera fold-thrust belt. Interpretations of seismic reflection profiles and field reconnaissance have suggested basin-wide stratigraphic sequences. Additionally, radiometric and magnetostratigraphic data constrain sequence deposition between approximately 17 and 4 Ma. However, a fundamental question remains unanswered: temporal variability of which control caused development of unconformity-bound nonmarine sequences? Prior to this work, hypotheses about the factors at play, notably tectonism and climate change, remained untested, and fieldwork provided only localized information about the nature of the sequences. The present study examines basin lithofacies more broadly and will independently constrain discharge history (a proxy for climate) and intrabasinal tectonics. Thus far, fuller knowledge of the sedimentation patterns, structural expression, and volcanic history of Iglesia Basin is supplied by information from new outcrop localities near the northern paleomargin and basin center, and from reinterpretation of previously studied localities. A substantial volcanic component to the history of the oldest sequences is inferred from age relationships and continuity of deposits in proximity to the Cerro Negro intrabasinal andesitic center. Reassessment of field-assigned sequence boundaries in terms of continuity and expression, both along-strike and across intrabasinal faults, suggests that lithofacies shifts are more prevalent than erosive surfaces. Radiometric dating of additional tuffaceous units in the Tertiary sequences will allow more conclusive correlation among discontinuous outcrops. Floodplain assemblages of Aridosols and Inceptisols indicate

  13. Northwest Arid Lands : an introduction to the Columbia Basin shrub-steppe

    SciTech Connect

    O'Connor, Georganne P. ); Wieda, Karen J. )

    2001-04-15

    This book explores the rich variety of life in shrub-steppe lands of the Columbia River Basin. It describes, for a non-technical audience, the flora, fauna, and geology of the lower Columbia Basin in and around the Tri-Cities, Washington. Features include color photos and maps of shrub-steppe plants and animals; lists and illustration of common plants, mammals, reptiles, amphibians, birds, fish, and species of conservation concern; tips on places to see wildflowers and wildlife; geological travel logs from the Tri-Cities to Seattle and Spokane; and a comprehensive bibliography and definition of ecological terms.

  14. Managing stakeholders' conflicts for water reallocation from agriculture to industry in the Heihe River Basin in Northwest China.

    PubMed

    Wang, Xiaojun; Yang, Hong; Shi, Minjun; Zhou, Dingyang; Zhang, Zhuoying

    2015-02-01

    Along with the accelerating process of industrialization and urbanization, water reallocation from agriculture to industry will be an inevitable trend in most developing countries. In the inland river basin, inter-sectoral water transfer is likely to result in reallocation of water resources between upstream and downstream regions, and further triggers frictions and conflicts between regions. Designing effective policy measures to coordinate these conflicts among stakeholders is crucial for the successful implementation of water reallocation. This study established a participatory multi-attribute decision support model to seek a widely acceptable water allocation alternative in the Heihe River Basin, an arid region in Northwest China. The results indicate that: (1) intense conflicts arise not only among stakeholder groups but also between upstream and downstream regions in the process of water reallocation from agriculture to industry; (2) among the options which respectively emphasize on equity, efficiency, and sustainability, the combination of equity and efficiency is the least controversial alternative for the majority of stakeholder groups, although it is not the most desirable one in the performance of all sub-objectives; (3) the multi-attribute value theory (MAVT) approach is a useful technique to elicit stakeholder values and to evaluate water reallocation options. The technique can improve the transparency and credibility of decision making in the water management process. PMID:25461085

  15. Analysis of agricultural land use change in the middle reach of the Heihe River Basin, Northwest China.

    PubMed

    Fu, Li; Zhang, Lanhui; He, Chansheng

    2014-03-04

    The Heihe River Basin (HRB) is the second largest inland river basin in arid Northwest China. The expanding agricultural irrigation, growing industrialization, and increasing urban development in the middle reach have depleted much of the river flow to the lower reach, degrading the corresponding ecosystems. Since the enactment of the State Council of China's new HRB water allocation policy in 2000 tremendous land use and land cover (LULC) changes have taken place to reduce water consumption in the middle reach and deliver more water downstream. This paper analyzes LULC changes during the period of 2000-2009 to understand how the changing land use patterns have altered water resource dynamics in the region. Results, while yet to be further verified in the field, show that from 2000 to 2009, urban, agricultural land, rangeland, and forest areas have increased, and barren area has decreased. Within the cropland, rice (a high water consumption crop) planting area decreased, while corn and wheat (relatively lower water consumption crops) planting areas increased. These changes in land use patterns, especially in the agricultural zones, have ensured the discharge of the required amount of water to the lower reach.

  16. Managing stakeholders' conflicts for water reallocation from agriculture to industry in the Heihe River Basin in Northwest China.

    PubMed

    Wang, Xiaojun; Yang, Hong; Shi, Minjun; Zhou, Dingyang; Zhang, Zhuoying

    2015-02-01

    Along with the accelerating process of industrialization and urbanization, water reallocation from agriculture to industry will be an inevitable trend in most developing countries. In the inland river basin, inter-sectoral water transfer is likely to result in reallocation of water resources between upstream and downstream regions, and further triggers frictions and conflicts between regions. Designing effective policy measures to coordinate these conflicts among stakeholders is crucial for the successful implementation of water reallocation. This study established a participatory multi-attribute decision support model to seek a widely acceptable water allocation alternative in the Heihe River Basin, an arid region in Northwest China. The results indicate that: (1) intense conflicts arise not only among stakeholder groups but also between upstream and downstream regions in the process of water reallocation from agriculture to industry; (2) among the options which respectively emphasize on equity, efficiency, and sustainability, the combination of equity and efficiency is the least controversial alternative for the majority of stakeholder groups, although it is not the most desirable one in the performance of all sub-objectives; (3) the multi-attribute value theory (MAVT) approach is a useful technique to elicit stakeholder values and to evaluate water reallocation options. The technique can improve the transparency and credibility of decision making in the water management process.

  17. Tectonics of the Georgia Basin, northwest Washington State, USA, and southwest British Columbia, Canada

    NASA Astrophysics Data System (ADS)

    Polivka, Peter Michael

    GPS strain and recent neotectonic studies in northwest Washington and southwest British Columbia indicate long term north-south shortening of the Cascadia forearc extends north of recognized active faults. This study reviews seismic reflection profiles from the SHIPS 1998 and 2002 experiments in conjunction with industry data to identify active geologic structures capable of accommodating this unaccounted strain. Here a new active northeast striking thrust system in southern Strait of Georgia is identified, the fault ruptured during the 1997 earthquake near Gabriola Island and Vancouver B.C. is imaged, and the first subsurface images of the Sandy Point Fault are presented.

  18. Tectonic development of the Northwest Bonaparte Basin, Australia by using Digital Elevation Model (DEM)

    NASA Astrophysics Data System (ADS)

    Wahid, Ali; Salim, Ahmed Mohamed Ahmed; Ragab Gaafar, Gamal; Yusoff, AP Wan Ismail Wan

    2016-02-01

    The Bonaparte Basin consist of majorly offshore part is situated at Australia's NW continental margin, covers an area of approx. 270,000km2. Bonaparte Basin having a number of sub-basins and platform areas of Paleozoic and Mesozoic is structurally complex. This research established the geologic and geomorphologic studies using Digital Elevation Model (DEM) as a substitute approach in morphostructural analysis to unravel the geological complexities. Although DEMs have been in practice since 1990s, they still have not become common tool for mapping studies. The research work comprised of regional structural analysis with the help of integrated elevation data, satellite imageries, available open topograhic images and internal geological maps with interpreted seismic. The structural maps of the study area have been geo-referenced which further overlaid onto SRTM data and satellite images for combined interpretation which facilitate to attain Digital Elevation Model of the study area. The methodology adopts is to evaluate and redefine development of geodynamic processes involved in formation of Bonaparte Basin. The main objectives is to establish the geological histories by using digital elevation model. The research work will be useful to incorporate different tectonic events occurred at different Geological times in a digital elevation model. The integrated tectonic analysis of different digital data sets benefitted substantially from combining them into a common digital database. Whereas, the visualization software facilitates the overlay and combined interpretation of different data sets which is helpful to reveal hidden information not obvious or accessible otherwise for regional analysis.

  19. Substratum transverse faults in Kuqa Foreland Basin, northwest China and their significance in petroleum geology

    NASA Astrophysics Data System (ADS)

    Cai, Jun; Lü, Xiuxiang

    2015-08-01

    The importance of transverse faults in basin evolution and petroleum geology has been often emphasized. However, the transverse faults in the Kuqa Foreland Basin, the most important gas producing area in China, have rarely been studied. Interpreted seismic sections and earthquake focal mechanism solutions, as well as other geological and geophysical data, allow us to identify a few widely-spaced, approximately NS trending, transverse strike-slip faults separating major structural units, and to clarify the geometry and kinematics of these transverse faults hidden below thrust faults. In the Kuqa Foreland Basin, two major structural domains can be distinguished. Transverse faults in the northern Kuqa Foreland Basin are mainly NNE trending sinistral, indicating clockwise-rotation of fault-bounded blocks. In contrast, the predominant NW trending dextral faults in the southern Kuqa Foreland Basin imply counterclockwise-rotation of fault-bounded blocks. We propose a tectonic model in which crustal blocks are bounded by strike-slip faults in a zone of simple shear rotation about vertical axis. The strike-slip faulting and thrust faulting in the Kuqa Foreland Basin suggest that some of the convergence between South Tianshan and Tarim blocks may have been accommodated not only by obvious crustal shortening and thickening along thrust faults, but also by rotation and possible lateral movement of the crust along transverse faults. Controlled by the remote collision of Indian block with Eurasian block since the Miocene, these reactivated substratum faults, which may inherit from Paleozoic deformation, control various elements relevant to gas accumulation in the Kuqa Foreland Basin which should expect to be paid more attention in the future. These elements include maturity of Tertiary and Jurassic source rocks, a difference in the regional cap of Kumugelimu salt beds from east to west, reservoir bed properties, gas migration channels, and traps formation. In addition, the

  20. Linear and nonlinear characteristics of the runoff response to regional climate factors in the Qira River basin, Xinjiang, Northwest China.

    PubMed

    Xue, Jie; Gui, Dongwei

    2015-01-01

    The inland river watersheds of arid Northwest China represent an example of how, in recent times, climatic warming has increased the complexity of Earth's hydrological processes. In the present study, the linear and nonlinear characteristics of the runoff response to temperature and precipitation were investigated in the Qira River basin, located on the northern slope of the Kunlun Mountains. The results showed that average temperature on annual and seasonal scales has displayed a significantly increasing trend, but this has not been reflected in accumulated precipitation and runoff. Using path analysis, a positive link between precipitation and runoff was found both annually and in the summer season. Conversely, it was found that the impact of temperature on runoff has been negative since the 1960s, attributable to higher evaporation and infiltration in the Qira River basin. Over the past 50 years, abrupt changes in annual temperature, precipitation and runoff occurred in 1997, 1987 and 1995, respectively. Combined with analysis using the correlation dimension method, it was found that the temperature, precipitation and runoff, both annually and seasonally, possessed chaotic dynamic characteristics, implying that complex hydro-climatic processes must be introduced into other variables within models to describe the dynamics. In addition, as determined via rescaled range analysis, a consistent annual and seasonal decreasing trend in runoff under increasing temperature and precipitation conditions in the future should be taken into account. This work may provide a theoretical perspective that can be applied to the proper use and management of oasis water resources in the lower reaches of river basins like that of the Qira River. PMID:26244113

  1. Linear and nonlinear characteristics of the runoff response to regional climate factors in the Qira River basin, Xinjiang, Northwest China

    PubMed Central

    Xue, Jie

    2015-01-01

    The inland river watersheds of arid Northwest China represent an example of how, in recent times, climatic warming has increased the complexity of Earth’s hydrological processes. In the present study, the linear and nonlinear characteristics of the runoff response to temperature and precipitation were investigated in the Qira River basin, located on the northern slope of the Kunlun Mountains. The results showed that average temperature on annual and seasonal scales has displayed a significantly increasing trend, but this has not been reflected in accumulated precipitation and runoff. Using path analysis, a positive link between precipitation and runoff was found both annually and in the summer season. Conversely, it was found that the impact of temperature on runoff has been negative since the 1960s, attributable to higher evaporation and infiltration in the Qira River basin. Over the past 50 years, abrupt changes in annual temperature, precipitation and runoff occurred in 1997, 1987 and 1995, respectively. Combined with analysis using the correlation dimension method, it was found that the temperature, precipitation and runoff, both annually and seasonally, possessed chaotic dynamic characteristics, implying that complex hydro-climatic processes must be introduced into other variables within models to describe the dynamics. In addition, as determined via rescaled range analysis, a consistent annual and seasonal decreasing trend in runoff under increasing temperature and precipitation conditions in the future should be taken into account. This work may provide a theoretical perspective that can be applied to the proper use and management of oasis water resources in the lower reaches of river basins like that of the Qira River. PMID:26244113

  2. Basin and Range crustal and upper mantle structure, northwest to central Nevada

    SciTech Connect

    Catchings, R.D.; Mooney, W.D. )

    1991-04-10

    The authors present an interpretaton of the crustal and uppermost mantel structure of the Basin and Range of northwestern Nevada based on seismic refraction/wide-angle reflection, near-vertical reflection, and gravity data. In comparison to most previous estimates, they find that the crust is somehwat thicker (32-36 km versus 22-30 km), and the uppermost mantel velocity is somewhat higher (8.0 km/s versus 7.3-7.9 km/s). Variations in velocity and structure of the upper crustal layers reveal apparent basement velocity depressions that underlie some surface ranges as well as the basins. The middle crust rises from about 20 km beneath central Nevada to within 12 km of the surface beneath the area of thinnest crust and is characterized by a modest change in velocity and low-velocity gradients. These midcrustal layers mark the onset of high crustal reflectivity and the apparent limiting depth to which Basin and Range faults can be traced in near-vertical reflection profiles, suggesting that these midcrustal layers represent the transition between the brittle and ductile zones of the crust. The geometry of lower crustal layers (derived from refraction modeling) coincides with changes in the crustal reflectivity. Gravity modeling and comparison to existing seismic models show a general consensus in many aspects with respect to crustal structure. This new model forms the basis for speculation on some of the processes associated with rifting of the Basin and Range Province. One such process, lithospheric magmatism, is inferred from the strong attenuation of transmitted seismic waves, which occurs at the same interface at which high-amplitude, bright spot reflections originate. Unlike previous models, the overall structure and velocity of the crust and uppermost mantle of this model are similar to other regions worldwide which have undergone high degrees of extension.

  3. Petrography and geochemistry of lower carboniferous greywacke and mudstones in Northeast Junggar, China: Implications for provenance, source weathering, and tectonic setting

    NASA Astrophysics Data System (ADS)

    Tao, Huifei; Sun, Shu; Wang, Qingchen; Yang, Xiaofa; Jiang, Lin

    2014-06-01

    Northeast Junggar occupies an important position that links East Junggar and Chinese Altai. Numerous magmatic and sedimentary rocks of the Paleozoic in this area recorded the final amalgamation processes of East Junggar and Chinese Altai. This study analyzes the petrological and geochemical characteristics of sandstones and mudstones from the Early Carboniferous Nanmingshui formation in Northeast Junggar. The provenance and tectonic setting of these clastic rocks are discussed. Petrography indicates that the composition and texture maturity of the sandstones are low. The components of the sandstones are mainly volcanic fragments (61-87%), feldspars (9-30%), and monocrystalline quartz (2-18%), with a few polycrystalline quartz and other minerals. Slice observation indicates that the majority of the volcanic fragments of sandstones are basic-intermediate volcanic rocks with a few dacite and felsic plutonic fragments. The detrital modes of the sandstones reflect that these sandstones are derived from undissected arcs. A low to moderate chemical index of alteration and the Al2O3-CaO* + Na2O-K2O diagram reflect a low to moderate weathering degree in the source area. Trace and rare earth element (e.g., La, Th, Hf, Sc, Cr, Co, and Eu) contents and their ratios suggest that the source rocks of the clastic rocks are intermediate-basic rocks with some felsic rocks. Compared with sandstones, the source rocks for mudstones are more felsic. The petrography and geochemistry characteristics of the clastic rocks suggest that the proximal Dulate arc should be the primary source area. Mixing calculations based on REE data suggest that approximately two-thirds of the sandstone fragments are intermediate-basic volcanic rocks. The contents of the major and trace elements, as well as the stratum features, of the clastic rocks manifest that these clastic rocks resemble sedimentary rocks in a back-arc basin. The formation of this back-arc basin is caused by the southward subduction of the

  4. Structural style and petroleum prospects of the Kuqa depression, northern Tarim basin, northwest China

    SciTech Connect

    McKnight, C.L.; Hendrix, M.; Sobel, E.; Schulein, B.; Carroll, A.; Chu, J. )

    1990-05-01

    The Kuqa depression is a 400-km {times} 100-km, east-west-trending foredeep basin located on the northern margin of the Tarim craton in northwestern China. A 10-km-thick nonmarine Mesozoic and Cenozoic sedimentary section has accumulated in the basin as the Tian Shan range to the north and has been episodically uplifted and thrust southward, tectonically loading the craton margin and providing source areas for clastic sediments. Regional mapping from Landsat images and field reconnaissance reveal important details of the structural style of the Kuqa depression. The Kuqa depression is characterized by thin-skinned deformation resulting in a series of steep, faulted, elongate folds. Thick, mobile Tertiary shale sequences and an Upper Cretaceous-lower Tertiary evaporite section in the west form detachment horizons separating disharmonically deformed structural packages. At the southern margin of the depression, the Mesozoic-Cenozoic section overrides faulted Paleozoic strata of the North Tarim uplift. Here, the Neogene Qiulitage anticline extends 250 km along the basin margin. Beginning in 1984, several important oil discoveries have been made in the Paleozoic section on the North Tarim uplift. Analysis of an oil sample indicates its compatibility with a lower Paleozoic marine source. Other potential source rocks in the Kuqa depression include Jurassic oil shales and coals. Sandstone reservoir strata and structural trapping geometries are numerous, but exploration risks are complicated by the presence of the ductile evaporite and shale seals. If nonmarine source rocks are also present in the thick Cenozoic section, the Kuqa depression may be an attractive exploration target.

  5. Significance of loessite in the Maroon Formation (Middle Pennsylvanian to Lower Permian), Eagle Basin, northwest Colorado

    USGS Publications Warehouse

    Johnson, S.Y.

    1989-01-01

    The Maroon Formation includes a siltstone-dominated facies interpreted as loessite (lithified loess) along its downwind basin margin. The section of inferred loessite is locally at least 490 m thick and consists in large part of structureless and nearly structureless beds of homogeneous sandy siltstone. Bed contacts are generally planar to undulatory and are either horizontal or are characterized by gentle relief. Deposition of the Maroon Formation was probably strongly affected by cyclic climatic changes synchronous with fluctuations in late Paleozoic continental ice sheets. -from Author

  6. Geomorphic evidence of unrecognized Balapur fault segment in the southwest Kashmir basin of northwest Himalayas

    NASA Astrophysics Data System (ADS)

    Ahmad, Shabir; Alam, Akhtar; Ahmad, Bashir; Bhat, M. I.; Sultan Bhat, M.

    2015-12-01

    The Balapur fault (BF) is a high angle thrust fault (reverse), dipping ~ 60° NE, with an established length of ~ 40 km striking NW-SE of the Kashmir basin. However, geomorphic traces suggest that the strike of the BF propagates beyond what has been documented previously. The present investigation aims to identify the unrecognized segment of the BF in the SW of the Kashmir basin using hypsometric variability in longitudinal profiles (knickpoints/zones), followed by validation through stream gradient index (SL) calculations of the rivers draining the area. The longitudinal profiles of all the streams indicate prominent and consistent anomalies in the upper and mid-reaches even on the coarse resolution data (Survey of India topographic maps - 1:50,000/40 m, DEM-SRTM 90 m). The profile anomalies in the upper reaches (hard rock zone) of the streams may be attributed to lithological contacts, i.e., Panjal trap agglomeratic slate-shale-limestone. However, the river profile convex segments and course deflection specifically in the mid-reaches (soft rock zone) are most likely associated with recent tectonic activity. Geomorphic signatures suggest that these anomalies coincide with the strike of the recognized segment of the BF. Moreover, the SL values of each stream express a clear agreement with the anomalies shown by the long profiles of the rivers. Hence, we infer that the strike of the BF extends for a significant distance (~ 95 km) over the northeastern flank of the Pir Panjal range in the NW-SE direction.

  7. Age and tectonic evolution of the northwest corner of the West Philippine Basin

    NASA Astrophysics Data System (ADS)

    Doo, Wen-Bin; Hsu, Shu-Kun; Yeh, Yi-Ching; Tsai, Ching-Hui; Chang, Ching-Ming

    2015-09-01

    To understand the tectonic characteristics and age of the northwestern part of the West Philippine Basin (WPB), multi-beam bathymetry and geomagnetic data have been collected and analyzed. The seafloor morphology obviously shows NW-SE trending seafloor fabrics and NE-SW trending fracture zones, indicating a NE-SW seafloor spreading direction. An overlapping spreading center near 22°20'N and 125°E is identified. Besides, numerous seamounts indicate an excess supply of magma during or after the oceanic crust formation. A V-shaped seamount chain near 21°52'N and 124°26'E indicates a southeastward magma propagation and also indicates the location of the seafloor spreading ridge. On the basis of the newly collected geomagnetic data, the magnetic anomaly shows NW-SE trending magnetic lineations. Both bathymetry and geomagnetic data reveal NE-SW seafloor spreading features between the Gagua Ridge and the Luzon Okinawa fracture zone (LOFZ). Our magnetic age modeling indicates that the age of the northwestern corner of the WPB west of the LOFZ is between 47.5 to 54 Ma (without including overlapping spreading center), which is linked to the first spreading phase of the WPB to the east of the LOFZ. In addition, the age of the Huatung Basin is identified to be between 33 to 42 Ma, which is similar to the second spreading phase of the WPB.

  8. [Geochemistry of surface and ground water in the Lijang basin, Northwest Yunnan].

    PubMed

    Pu, Tao; He, Yuan-Qing; Zhu, Guo-Feng; Zhang, Wei; Cao, Wei-Hong; Chang, Li; Wang, Chun-Feng

    2012-01-01

    The study focused on the chemical element compositions of river water and groundwater in Lijiang Basin. Water samples were collected in Baishui, Sanshu, Geji and Shuhe rivers in Lijiang Basin to analyze pH, conductivity and ion concentration, in order to understand the contributions of anthropogenic activities and rock weathering to river solutes. The results show that all water samples are mildly alkaline and are rich in Ca2+ and HCO3-, which account for 54.8 and 92.4 percentage of total ion concentration respectively. Obvious variations have been perceived during monsoon and westward wind season. The ion concentration of river water is lower than that of groundwater. With decreasing elevation, the ion concentrations are found to increase considerably in the study region. According to source study of major ions, water chemistry is mainly influenced by precipitation rock weathering and dissolving processes. In addition, precipitation is an important factor in monsoon seasons whereas the anthropogenic inputs have lead to light pollution on water in residential district.

  9. Significance and Effect of Ecological Rehabilitation Project in Inland River Basins in Northwest China

    NASA Astrophysics Data System (ADS)

    Wang, Yu; Feng, Qi; Chen, Lijuan; Yu, Tengfei

    2013-07-01

    The Ecological Water Transfer and Rehabilitation Project in the arid inland area of northwest China is an important measure in restoring a deteriorated ecosystem. However, the sustainability of the project is affected by many socio-economic factors. This article examines the attitudes of the local populace toward the project, its impact on the livelihood of the people, and the positive effects of water-efficient agricultural practices in Ejina County. Related data were collected through questionnaire surveys and group discussions. The results identified three critical issues that may influence the sustainability of the project in the study area. The first issue relates to the impact of the project on the livelihood of local herdsmen. The potential for the sustainability of the project is compromised because the livelihood of the herdsmen greatly depends on the compensation awarded by the project. The second issue is that the project did not raise the water resource utilization ratio, which may undermine its final purpose. Finally, the compensation provided by the project considers losses in agriculture, but neglects the externalities and public benefit of eco-water. Thus, appropriate compensation mechanisms should be established and adopted according to local economic, environmental, and social conditions. Some recommendations for improving the sustainability of the project are provided based on the results of this study.

  10. Siliciclastic Progradation Within a Neogene Carbonate Passive Margin - Northern Carnarvon Basin of the Northwest Shelf of Australia

    NASA Astrophysics Data System (ADS)

    Sanchez, C. M.; Fulthorpe, C. S.; Austin, J. A.

    2008-12-01

    Interpretations of extensive industry subsurface data (3D and 2D seismic data, wireline logs and completion reports) and results from previous studies suggest that relative sea level changes and ocean currents controlled observed variations in carbonate vs. siliciclastic sediment type and stratal architecture in the Northern Carnarvon Basin, Northwest Shelf of Australia, during the Neogene. The basin has been a site of predominantly carbonate sedimentation since the late Paleogene. However, significant (at least 30-70 km) siliciclastic progradation on top of this carbonate shelf started in the late middle Miocene. Carbonate- dominated sedimentation resumed in the late Miocene/Pliocene. Siliciclastic-rich seismic packages show dip- oriented progradation northwestward, as well as strike-oriented progradation northeastward. Clinoform heights, up to approx. 140 m, and a dip-elongated lobe morphology suggest deposition by a long-lived (approx. 6 My) deltaic system which is no longer active on this margin. Consistent northeastward switching of these interpreted delta lobes and their progradation over the preexisting carbonate shelf sediments suggest wave-dominated conditions, with strong northeastward long-shore currents, for this delta system during a time of relative base level fall. During this siliciclastic progradation event, carbonate sedimentation continued in the updrift direction southwest of the delta, but carbonates were not accumulated downdrift or northeast, where progressively younger deltaic siliciclastics filled available accommodation space. By the beginning of the Pliocene, siliciclastic sedimentation had retreated towards the Australian coast, allowing widespread carbonate production to resume; interpreted shallow-water carbonate platforms then developed over subtle topographic highs created by the underlying deltaic lobes.

  11. Transpiration and canopy conductance variations of shelterbelt in an arid inland river basin of northwest China

    NASA Astrophysics Data System (ADS)

    Gao, G.

    2015-12-01

    The knowledge of plant water use characteristics under changing environmental conditions is essential for ecosystem management and water resources distribution in water-stressed environments. This study was conducted to quantify variations in transpiration and canopy conductance in a shelterbelt in the middle of the Heihe River Basin, China. Sap flow of eight Gansu Poplar trees (Populus gansuensis) with different diameters at breast height (DBH) was measured over three consecutive growing seasons (2012-2014). The evapotranspiration of groundwater via plant use was estimated by the White method, with diurnal water table fluctuations. Results showed that mean sap flow density varied between 30.62 ±11.44 and 101.88 ±28.98 kg m-2 h-1, and it increased linearly with the DBH. Variations of sap flow density were mainly controlled by meteorological factors in addition to water table depth. Average stand transpiration during the growing season was about 4.85 mm day-1, and it had a logarithmic relationship with reference crop evapotranspiration. Precipitation increased stand transpiration, but not at a statistically significant level (p>0.05). The recharge of soil water by irrigation significantly accelerated stand transpiration (p<0.05). Stand transpiration and canopy conductance increased by 27% and 31%, respectively, when soil water conditions changed from dry to wet. Canopy conductance decreased logarithmically with vapor pressure deficit, whereas there was no apparent relationship between canopy conductance and solar radiation. The sensitivity of canopy conductance to vapor pressure deficit decreased under dry soil conditions. Groundwater evapotranspiration (0.6-7.1 mm day-1) was linearly correlated with stand transpiration (1.1-6.5 mm day-1) (R2 = 0.71). During the drought period, approximately 80% of total stand transpiration came from groundwater evapotranspiration. This study highlighted the critical role of irrigation and groundwater for shelterbelts, and might

  12. Structural and stratigraphic mapping from satellite imagery, Kalpin uplift, northwestern Tarim basin, northwest China

    SciTech Connect

    McKnight, C.L.; Carroll, A.R.; Chu, J.; Hendrix, M.S.; Graham, S.A.; Lyon, R.J.P. )

    1990-05-01

    The Kalpin uplift, located on the northwestern margin of the Tarim craton, northwest China, exposes a complete Paleozoic cratonal stratigraphic sequence. The lack of vegetative cover and the visible color contrasts between stratigraphic units afford an optimal situation for detailed geologic mapping from Landsat Multispectral Scanner imagery at a scale of 1:250,000. Field work in the eastern Kalpin uplift constrains the geologic interpretation of the satellite imagery. Exposed basement rock in the Kalpin uplift consists of deformed and metamorphosed upper Proterozoic strata cut by unmetamorphosed mafic dikes. The overlying sedimentary section was deposited primarily in shallow marine to nonmarine environments and includes Sinian (latest Proterozoic to early Cambrian) siliciclastics and carbonates; Cambrian and Ordovician carbonates; Silurian green shales; Devonian red beds; Carboniferous siliciclastics and carbonates; and Permian carbonates, siliciclastics, and subaerial basalt flows. Paleozoic strata are exposed in a series of low, parallel, curvilinear ranges located at the leading edges of low-angle, southeast-vergent thrust sheets. The regular thrust repetition of the entire Paleozoic section suggests the presence of a detachment horizon within the Cambrian section. These southeast-vergent thrust sheets override an older structural trend on the craton, the Bachu uplift, at right angles, folding as they do so. Strike-slip faults cutting the thrust sheets along the same trend as the Bachu uplift suggest the location of buried lateral ramps associated with the Bachu uplift. The young deformation in the Kalpin uplift is a response to compressive stresses produced by the northward movement of the Indian plate. Major faults in the Tian Shan mountain range to the north have been reactivated, resulting in southward-directed thrusting over the Tarim craton.

  13. Assessment of spatial and temporal patterns of green and blue water flows under natural conditions in inland river basins in Northwest China

    NASA Astrophysics Data System (ADS)

    Zang, C. F.; Liu, J.; van der Velde, M.; Kraxner, F.

    2012-08-01

    In arid and semi-arid regions freshwater resources have become scarcer with increasing demands from socio-economic development and population growth. Until recently, water research and management has mainly focused on blue water but ignored green water. Furthermore, in data poor regions hydrological flows under natural conditions are poorly characterised but are a prerequisite to inform future water resources management. Here we report on spatial and temporal patterns of both blue and green water flows that can be expected under natural conditions as simulated by the Soil and Water Assessment Tool (SWAT) for the Heihe river basin, the second largest inland river basin in Northwest China. Calibration and validation at two hydrological stations show good performance of the SWAT model in modelling hydrological processes. The total green and blue water flows were 22.05-25.51 billion m3 in the 2000s for the Heihe river basin. Blue water flows are larger in upstream sub-basins than in downstream sub-basins mainly due to high precipitation and a large amount of snow and melting water in upstream. Green water flows are distributed more homogeneously among different sub-basins. The green water coefficient was 87%-89% in the 2000s for the entire river basin, varying from around 80%-90% in up- and mid-stream sub-basins to above 90% in downstream sub-basins. This is much higher than reported green water coefficients in many other river basins. The spatial patterns of green water coefficients were closely linked to dominant land covers (e.g. snow cover upstream and desert downstream) and climate conditions (e.g. high precipitation upstream and low precipitation downstream). There are no clear consistent historical trends of change in green and blue water flows and the green water coefficient at both the river basin and sub-basin levels. This study provides insights into green and blue water endowments under natural conditions for the entire Heihe river basin at the sub-basin

  14. Geophysical evidence for fluid flow in the Laminaria High, Bonaparte basin, Northwest shelf of Australia

    NASA Astrophysics Data System (ADS)

    Abdulkareem, Lamees; Hobbs, Richard; Imber, Jonathan

    2016-04-01

    Seismic amplitude anomalies ("bright spots") can result from changes in acoustic impedance caused by the presence of fluids and/or lateral changes in lithology. In this study, 3D seismic interpretation and well log data is used to investigate the nature and causes of seismic amplitude anomalies within the shallow subsurface on the Laminaria High on the north-west shelf of Australia. Here, the anomalies are associated with active faults that cut the seabed. Previous studies suggest that fault reactivation and fault geometry have an important role in causing hydrocarbon leakage from a deeper reservoir and that bends on the larger faults will influence the localization of shear strain, increasing the risk of leakage. However, these studies did not examine the influence of fault growth during reactivation on fluid migration, or how post-rift and syn-rift sedimentation may have influenced fluid leakage. In our study, preliminary results suggest that not all active faults are associated with amplitude anomalies or dry/partially-filled hydrocarbon traps at depth, implying that there could be a different mechanism for the creation of the amplitude anomaly observed on the Laminaria High. Specifically, these anomalies may be the result of preferential cementation, or the presence of gas trapped within sediments at or near the seabed, possibly originating from gas generation due to biogenic activity in recently deposited sediment. Detailed amplitude maps are extracted from syn- and pre- faulting seismic horizons down to the top reservoir level in order to understand the spatial extent of the high amplitude anomalies within the stratigraphic succession. The first two amplitude maps for the seismic horizons beneath the seabed show high amplitude anomalies associated with the same active faults that are present on the seabed, but with some different characteristics along these faults. Then we extract number of deeper amplitude maps to the top of reservoir, to reveal whether the

  15. The Timan-Pechora Basin province of northwest Arctic Russia; Domanik, Paleozoic total petroleum system

    USGS Publications Warehouse

    Lindquist, Sandra J.

    1999-01-01

    The Domanik-Paleozoic oil-prone total petroleum system covers most of the Timan-Pechora Basin Province of northwestern Arctic Russia. It contains nearly 20 BBOE ultimate recoverable reserves (66% oil). West of the province is the early Precambrian Eastern European craton margin. The province itself was the site of periodic Paleozoic tectonic events, culminating with the Hercynian Uralian orogeny along its eastern border. The stratigraphic record is dominated by Paleozoic platform and shelf-edge carbonates succeeded by Upper Permian to Triassic molasse siliciclastics that are locally present in depressions. Upper Devonian (Frasnian), deep marine shale and limestone source rocks ? with typically 5 wt % total organic carbon ? by middle Mesozoic time had generated hydrocarbons that migrated into reservoirs ranging in age from Ordovician to Triassic but most focused in Devonian and Permian rocks. Carboniferous structural inversions of old aulacogen borders, and Hercynian (Permian) to Early Cimmerian (Late Triassic to Early Jurassic) orogenic compression not only impacted depositional patterns, but also created and subsequently modified numerous structural traps within the province.

  16. [Effects of land use change on landscape pattern vulnerability in Yinchuan Basin, Northwest China].

    PubMed

    Ren, Zhi-yuan; Zhang, Han

    2016-01-01

    Landscape pattern vulnerability reflects the instability and sensitivity of ecological system to external disturbances and helps to understand the status and trend of ecological environment. This paper used landscape sensitivity index and landscape adaptability index to construct the landscape pattern vulnerability index of Yinchuan Basin, and got the distribution of the landscape pattern vulnerability in 2001 and 2013. Our study explored the effect of the land use degree composite index, the integrated land use dynamic degree, the importance index of land use change and various types of land transfer on landscape pattern vulnerability. Results showed that the land use degree composite index was mainly caused by the increase of the arable land, forest and the construction land. The higher proportion of the arable land or forest, the lower the vulnerability was, and the construction land had the opposite effect. With the increase of integrated land use dynamic degree, the construction land significantly increased the vulnerability, followed by grassland, and the forest significantly decreased the vulnerability, followed by the arable land. As the importance index of land use change increasing, the arable land could significantly decrease the vulnerability, followed by the forest, the grassland had a weaker trend with no obvious pattern, and the construction land significantly increased the vulnerability. When the arable land, forest and the grassland were the maintypes of land use transfer, the increasing proportion of the construction land increased the vulnerability. When the construction land was the main type of land use transfer, the grassland and forest improved the vulnerability and the arable land had the opposite effect. Changes in the number of land use types influenced the spatial structure of land use to a certain extent, which could offer a reference on using and developing the land resources scientifically. The ternary diagram could reflect the impact

  17. [Effects of land use change on landscape pattern vulnerability in Yinchuan Basin, Northwest China].

    PubMed

    Ren, Zhi-yuan; Zhang, Han

    2016-01-01

    Landscape pattern vulnerability reflects the instability and sensitivity of ecological system to external disturbances and helps to understand the status and trend of ecological environment. This paper used landscape sensitivity index and landscape adaptability index to construct the landscape pattern vulnerability index of Yinchuan Basin, and got the distribution of the landscape pattern vulnerability in 2001 and 2013. Our study explored the effect of the land use degree composite index, the integrated land use dynamic degree, the importance index of land use change and various types of land transfer on landscape pattern vulnerability. Results showed that the land use degree composite index was mainly caused by the increase of the arable land, forest and the construction land. The higher proportion of the arable land or forest, the lower the vulnerability was, and the construction land had the opposite effect. With the increase of integrated land use dynamic degree, the construction land significantly increased the vulnerability, followed by grassland, and the forest significantly decreased the vulnerability, followed by the arable land. As the importance index of land use change increasing, the arable land could significantly decrease the vulnerability, followed by the forest, the grassland had a weaker trend with no obvious pattern, and the construction land significantly increased the vulnerability. When the arable land, forest and the grassland were the maintypes of land use transfer, the increasing proportion of the construction land increased the vulnerability. When the construction land was the main type of land use transfer, the grassland and forest improved the vulnerability and the arable land had the opposite effect. Changes in the number of land use types influenced the spatial structure of land use to a certain extent, which could offer a reference on using and developing the land resources scientifically. The ternary diagram could reflect the impact

  18. Application of Snowmelt Runoff Model (SRM) in ungagged Manasi River Basin, Northwest China

    NASA Astrophysics Data System (ADS)

    Chen, X.; Liang, S.; Bao, A.

    2014-12-01

    The climate change will have great impacts on snowmelt runoff, including prolong of snowmelt period, advance of peak in snowmelt discharges, and the notable increase of snowmelt volume in melt-season. These changes have great significance and caused widespread concerns in arid region because the snowmelt runoff is one of the most important water resources which seriously related to the agricultural and socio-economic development. However, limited by the poor geographical environment and spare distribution of in situ observations, the snowmelt runoff simulation are still a challenge in some ungagged catchment. The Snowmelt Runoff Model (SRM) is one of the few models in the world that requires remote sensing derived snow cover as model input. Based on the SRM hydrological model, this study simulated the snowmelt process in melt-season of 2007 in Manasi River Basin and try to make contribution to the understanding of snowmelt runoff process in such ungagged catchment. The conclusions are as follows: the SRM model represented a certain semi-distributed model with physical mechanism, has a good applicability in scarcely meteorological and hydrological suits distributed catchments. The correlation coefficient between computed runoff and measured runoff could reach 0.93 with 2.57% volume derivation in ideal situation without the effects of instantaneous precipitation during March-Jun, 2007. As one of the most important input variables, the daily snow cover extent derived from MOD10A1 are effectively make up the lack of in suit snow observations. The classification accuracy of MOD10A1 reached 0.81 in 95% confidence level on 3×3 pixels statistical scale verified by the Landsat 5 TM images. Meanwhile, temperature and precipitation played important roles on snowmelt runoff simulation, the correlation coefficient between daily temperature and daily measured runoff is 0.46 in 95% confidence level. The lase rate of discharge determined the basic shape of computed runoff, while

  19. Empirical relations of rock properties of outcrop and core samples from the Northwest German Basin for geothermal drilling

    NASA Astrophysics Data System (ADS)

    Reyer, D.; Philipp, S. L.

    2014-09-01

    Information about geomechanical and physical rock properties, particularly uniaxial compressive strength (UCS), are needed for geomechanical model development and updating with logging-while-drilling methods to minimise costs and risks of the drilling process. The following parameters with importance at different stages of geothermal exploitation and drilling are presented for typical sedimentary and volcanic rocks of the Northwest German Basin (NWGB): physical (P wave velocities, porosity, and bulk and grain density) and geomechanical parameters (UCS, static Young's modulus, destruction work and indirect tensile strength both perpendicular and parallel to bedding) for 35 rock samples from quarries and 14 core samples of sandstones and carbonate rocks. With regression analyses (linear- and non-linear) empirical relations are developed to predict UCS values from all other parameters. Analyses focus on sedimentary rocks and were repeated separately for clastic rock samples or carbonate rock samples as well as for outcrop samples or core samples. Empirical relations have high statistical significance for Young's modulus, tensile strength and destruction work; for physical properties, there is a wider scatter of data and prediction of UCS is less precise. For most relations, properties of core samples plot within the scatter of outcrop samples and lie within the 90% prediction bands of developed regression functions. The results indicate the applicability of empirical relations that are based on outcrop data on questions related to drilling operations when the database contains a sufficient number of samples with varying rock properties. The presented equations may help to predict UCS values for sedimentary rocks at depth, and thus develop suitable geomechanical models for the adaptation of the drilling strategy on rock mechanical conditions in the NWGB.

  20. [Coupling effect of water and nitrogen on spring maize in Wuwei Oasis of Shiyang River Basin, Northwest China].

    PubMed

    Liu, Xiao-gang; Zhang, Fu-cang; Yang, Qi-liang; Tian, Yu-feng; Li, Zhi-jun

    2013-08-01

    To explore the optimal supply model of water and nitrogen for spring maize under limited irrigation in arid Northwest China, a field experiment with orthogonal design was conducted in the Wuwei Oasis region margin of Shiyang River Basin to study the effects of irrigation amount at different growth stages and the nitrogen application rate on the group yield and the water and nitrogen utilization of spring maize. With the increase of nitrogen application rate, the grain yield of spring maize increased, and the highest grain yield was obtained when the nitrogen application rate was 300 kg x hm(-2) and the irrigation amount at jointing stage was 136 mm. The grain irrigation water use efficiency (GIWUE) decreased with increasing irrigation amount. When the irrigation amount in whole growth period was 340 mm, the grain yield and GIWUE were improved simultaneously with increasing nitrogen application rate. The GIWUE reached the maximum when the nitrogen application rate was 300 kg x hm(-2) and the irrigation amount at seedling and grain-filling stages was 34 mm, respectively. The effects of nitrogen application and irrigation on the nitrogen accumulation in the whole plant decreased in the order of nitrogen application rate, irrigation at jointing stage, irrigation at seedling stage, irrigation at grain-filling stage, and irrigation at heading stage. The optimal supply model of water and nitrogen for spring maize in Wuwei Oasis was 300 kg x hm(-2) of nitrogen application plus 34, 136, 68 and 102 mm of irrigation at seedling, jointing, heading and grain-filling stages, respectively.

  1. Testing new methodologies and assessing their potential for reservoir characterisation: Geoelectrical studies in the Northwest Carboniferous Basin (Ireland).

    NASA Astrophysics Data System (ADS)

    Ogaya, Xènia; Campanyà, Joan; Rath, Volker; Jones, Alan G.; Reay, Derek; Raine, Rob; McConnell, Brian; Ledo, Juanjo

    2016-04-01

    The overarching objective of this study is to improve our methods of characterising saline aquifers by integrating newly acquired electromagnetic data with existing geophysical and geological data. The work presented here is part of an ongoing project to evaluate Ireland's potential for onshore carbon sequestration (IRECCSEM; funded by Science Foundation Ireland). The methodology presented in this characterisation work is not only relevant for studying the potential for onshore carbon sequestration, but is generally applicable for aquifer characterisation, particularly for the evaluation of geothermal resources in appropriate geological settings. We present first results of the three-dimensional (3D) modelling and inversion of the magnetotelluric (MT) data acquired in the Northwest Carboniferous Basin (Ireland) in summer 2015. The electrical resistivity distribution beneath the survey area is constrained using a joint inversion of three different types of electromagnetic data: MT impedance tensor responses (Z), geomagnetic transfer functions (GTF) and inter-station horizontal magnetic transfer-functions (HMT). The preliminary 3D resistivity model obtained reveals the geoelectrical structure of the subsurface, which is translated into parameters relevant to fluid flow. The electromagnetic data were acquired along profiles linking four wells drilled in the area and the available well log data from those wells are used to evaluate some of the existing petrophysical relationships and calibrate them for the study area. This allows us to interpolate the rock physical properties from one well to another well, using the computed geoelectrical model as a reference. The obtained results are compared to available independent geological and geophysical data in order to analyse the validity of this technique, to characterise the uncertainties inherent to our approach, and to assess the potential of this methodology for reservoir characterisation.

  2. Tectonic evolution of the East Junggar terrane, CAOB

    NASA Astrophysics Data System (ADS)

    Xu, Xing-Wang

    2016-04-01

    The East Junggar terrane is one of the important tectonic units of the Central Asian Orogenic Belt (CAOB; Zonenshain et al., 1990). Debate surrounds the tectonics of the East Junggar area, including tectonic setting, age, basement nature, subduction polarity and collisional time between the East Junggar terrane and Junggar block (e.g., Xiao et al., 2008, 2011; Long et al., 2012; Huang et al., 2012). Among the two popular models, one suggests that the Junggar is a continental block (e.g. Zhang et al., 1984, 1993; Watson et al., 1987; Xiao et al., 1992; He et al., 1994; Li et al., 2000; Charvet et al., 2001, 2007; Xu et al., 2003; Zhao et al., 2003; Buslov et al., 2004; Xu and Ma, 2004; Dong et al., 2009; Bazhenov et al., 2012; Choulet et al., 2012; Zhang et al., 2012). The other model proposes that the Junggar has a basement of Paleozoic oceanic crust (e.g., Carroll et al., 1990; Zheng et al., 2007) or oceanic island arc complexes (e.g., Coleman, 1989; Chen and Jahn, 2004; Windley et al., 2007) of the Altaid Paleozoic rocks (e.g., Sengör et al., 1993; Sengör and Natal'in, 1996; Allen and Vincent, 1997; Filippova et al., 2001; Xiao et al., 2004a, 2004b, 2008, 2009, 2010a, 2010b, 2012). The tectonics in the Eastern Junggar area are interpreted to be related to late Paleozoic intra-oceanic accretion induced by northward subduction of the Junggar oceanic lithosphere (e.g. Xiao et al., 2008, 2009; Biske and Seltmann, 2010; Wan et al., 2011; Yang et al., 2011) or by the southward subduction of the Paleo-Asian oceanic lithosphere (Zhang et al., 2004; Wong et al., 2010; Su et al., 2012). Recently, we did detailed field survey and petrological, geochemical and chronological analysis of the metamorphosed volcanic rocks and magmatic rocks, and new discovered gneiss and magnetite quartzite enclaves from the Taheir tectonic window in the East Junggar region which is situated between the Zaisan-Erqis-the Main Mongolian Lineament-suture and the Kelameili suture. The new results

  3. Strain partitioning of the Red River fault system explains the initiation of the Yinggehai Basin in the northwest region of South China Sea

    NASA Astrophysics Data System (ADS)

    Wang, X.; He, J.; Ding, L.; Gao, R.; Ai, C.; Wang, X.; Pan, Z.

    2012-12-01

    The NW-trending Yinggehai Basin (YGHB), located around the Red River fault system (RRFS) in the northwest area of South China Sea (SCS), is an important petroleum-bearing province and characterized by a maximum sedimentation thickness of up to 17 km, a strong upwelling of Moho at 22-23 km depth, an average heat flow of 86 mW/m2, and diapirs structure. The YGHB is suggested to be closely related to the crustal deformation associated with displacements of the RRFS and the formation of the SCS, but the basin differs in its formation from the NE-trending Pearl River Mouth Basin and Qingdongnan Basin on the northern continental margin of SCS and the Yuanjiang Basin and Midu Basin along the RRFS. Based on a first-order estimate of the rheology and boundary condition of the YGHB, we developed a 2.5 dimensional finite element model to investigate the origin of the YGHB and the relationships between motions on the RRFS and the spreading of the SCS. The crustal rheology is simplified as an elasto-plastic upper crust and a visco-elastic lower crust. Possible lateral variations of viscosity in the lower crust are tested according to the tectonic setting of the basin region. Results show that associated with the regional crustal movements, deformation of the RRFS could be responsible for upper crustal extension on both its sides. Further, the style of extensional faulting around the RRFS is largely controlled by the rheology of the lower crust. This means that strain partitioning induced both by the transtensional loading of strike-slip fault system and by the lateral changes in rheology of the lower crust can result in normal faulting on both sides near the RRFS, and may be involved in the formation of the YGHB.

  4. Sustainable Agricultural Paradigm Of mountain-Oasis-Ecotone-Desert System in Inland Manasi River Basin, Xinjiang Province, Northwest China

    NASA Astrophysics Data System (ADS)

    Liu, Huiming; Chen, Weiming; Dong, Xiaobin; Zhang, Xinshi

    Manasi River basin is located in the north foot of Tianshan Mountain, south edge of Zhunger Basin, central-north Xinjiang province, with typical aridfeatures of northern China. As the pressure on water resources in Manasi river basin is mounting because of rapid economic development, its conservation becomes ever more important. Climate change is another major threat to the future of water resources of Manasi river basin. How the water resourcechanges in Manasi river basin caused by glacial ablation, will affect the typical mountain-basin terrestrial ecosystems and agricultural production in Manasi river basin? What can we cope with the ecological issues caused by glacial ablation? In this paper we show how the water-saving stratagem such asconstructing reservoir in the mountainous region, building water pipes and be used in combination with the potential of water-saving resources, and build up sustainable agricultural paradigm of mountain-oasis-ecotone-desert system to coping with the glacier retreat and ablation. The potential of water-saving instudy area were calculated which presumed that if mountainous reservoirs and water pipes were built and water-saving technology were adopted, optimized eco-productive paradigm for mountain-basin system in Manasi river basin is proposed in desertification controlling, constructing artificial grassland in the oasis is the measure to protect vegetation in the downstream desert in Manasi river basin, and stopping grazing or forbidding grazing in the downstream of serious degradation in Manasi river basin.

  5. Subsurface structure and stratigraphy of the northwest end of the Turkana Basin, Northern Kenya Rift, as revealed by magnetotellurics and gravity joint inversion

    NASA Astrophysics Data System (ADS)

    Abdelfettah, Yassine; Tiercelin, Jean-Jacques; Tarits, Pascal; Hautot, Sophie; Maia, Marcia; Thuo, Peter

    2016-07-01

    In order to understand the subsurface stratigraphy and structure of the northwest end of the Turkana Basin, Northern Kenya Rift, we used 2-D joint inversion of magnetotelluric (MT) and gravity data acquired along 3 profiles perpendicular to the main Murua Rith-Lapur Rift Border Fault. The regional geology is characterized by a basement of Precambrian age overlain by a ≤500-m thick sandstone formation named the Lapur Sandstone of upper Cretaceous-lower Eocene in age, covered by thick rhyolitic and basaltic lavas of late Eocene-middle Miocene age, known as the "Turkana Volcanics". Final interpretation of the resistivity and density models, until 5 km depth, obtained by the joint inversion approach confirms the previous general knowledge about the half-graben geometry of the northern part of the Turkana Basin. The main Murua Rith-Lapur Rift Border Fault is well identified by both gravity and MT. At least, two other important secondary faults without surface expression are also identified. A new small half-graben basin, named the Kachoda Basin, parallel to the main Turkana Basin and filled by 1.5 km of sediments, has been also characterized. This study also highlights strong thickness variations of the three main geological units that could be expected in the subsurface of the Turkana Basin. For example, the sedimentary Nachukui and Kibish Formations reach up to >3 km in thickness at the eastern end of the north and central profiles. Lateral variations of the topography of the Precambrian basement are also evidenced. Conceptual geological models, which result from the combination of the obtained density and resistivity models as well as from geological and reflection seismic data, are proposed. In such an area of intensive and promising oil exploration, these models are essential in terms of identification of reservoirs, source rocks and trapping mechanisms.

  6. Subsurface structure and stratigraphy of the northwest end of the Turkana Basin, Northern Kenya Rift, as revealed by magnetotellurics and gravity joint inversion

    NASA Astrophysics Data System (ADS)

    Abdelfettah, Yassine; Tiercelin, Jean-Jacques; Tarits, Pascal; Hautot, Sophie; Maia, Marcia; Thuo, Peter

    2016-07-01

    In order to understand the subsurface stratigraphy and structure of the northwest end of the Turkana Basin, Northern Kenya Rift, we used 2-D joint inversion of magnetotelluric (MT) and gravity data acquired along 3 profiles perpendicular to the main Murua Rith-Lapur Rift Border Fault. The regional geology is characterized by a basement of Precambrian age overlain by a ≤500-m thick sandstone formation named the Lapur Sandstone of upper Cretaceous-lower Eocene in age, covered by thick rhyolitic and basaltic lavas of late Eocene-middle Miocene age, known as the "Turkana Volcanics". Final interpretation of the resistivity and density models, until 5 km depth, obtained by the joint inversion approach confirms the previous general knowledge about the half-graben geometry of the northern part of the Turkana Basin. The main Murua Rith-Lapur Rift Border Fault is well identified by both gravity and MT. At least, two other important secondary faults without surface expression are also identified. A new small half-graben basin, named the Kachoda Basin, parallel to the main Turkana Basin and filled by 1.5 km of sediments, has been also characterized. This study also highlights strong thickness variations of the three main geological units that could be expected in the subsurface of the Turkana Basin. For example, the sedimentary Nachukui and Kibish Formations reach up to >3 km in thickness at the eastern end of the north and central profiles. Lateral variations of the topography of the Precambrian basement are also evidenced. Conceptual geological models, which result from the combination of the obtained density and resistivity models as well as from geological and reflection seismic data, are proposed. In such an area of intensive and promising oil exploration, these models are essential in terms of identification of reservoirs, source rocks and trapping mechanisms.

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

    NASA Astrophysics Data System (ADS)

    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

  8. Evaluation of the pollution and human health risks posed by heavy metals in the atmospheric dust in Ebinur Basin in Northwest China.

    PubMed

    Abuduwailil, Jilili; Zhaoyong, Zhang; Fengqing, Jiang

    2015-09-01

    Recently, a large amount of research assessing pollution levels and the related health risks posed by atmosphere dust has been undertaken worldwide. However, little work has been done in the oases of the arid regions of Northwest China. In this paper, we studied the pollution and health risks over a year of seven heavy metals in the atmospheric dust of Ebinur Basin, a typical oasis in Northwest China. The results showed the following: (1) The annual amount of atmospheric deposition in Ebinur Basin was 298.23 g m(-2) and the average monthly atmospheric deposition was 25.06 g m(-2). The average and maximum values of the seven heavy metals measured were all below the National Soil Environmental Quality Standards (2nd). (2) Heavy metals of Cu, Cr, and As in the atmospheric deposition mainly originated from the natural geological background, while Zn came from human activity. This study also showed that among the seven measured heavy metals, the ratios of the no-pollution status of Pb, Cd, and Hg were higher than those of others with moderate degrees of pollution also accounting for a certain ratio. (3) The carcinogenic risks from As, Cd, and Cr were all lower than the corresponding standard limit values, and these metals are considered not harmful to the health of the basin. However, there is a relatively high risk of exposure for children from hand-to-mouth intake, which is worthy of attention. This research showed that both human activity and natural factors, such as wind and altitude, influenced the heavy metal contents in the atmospheric dust of the study area. Furthermore, recent human activity in the study area had the most negative influence on the accumulation of the heavy metals and the corresponding health risks, especially for Hg, Pb, and Cd, which is worthy of attention.

  9. StreamNet; Northwest Aquatic Resource Information Network - Status of Salmon and Steelhead in the Columbia River Basin, 1995 Final Report.

    SciTech Connect

    Anderson, Duane A.; Beamesderfer, Raymond C.; Woodard, Bob

    1996-04-01

    Information on fish populations, fisheries, and fish habitat is crucial to the success of ongoing program to protect, recover, enhance, and manage fish resources in the Columbia River Basin. However, pertinent data are often difficult to locate because it is scattered among many agencies and is often unpublished. The goal of this annual report is to bring many diverse data types and sources into a single comprehensive report on the status of anadromous fish runs in the Columbia River Basin and the environmental conditions that may affect that status. Brief summaries are provided to identify the type and scope of available information. This synopsis is intended to complement other more detailed reports to which readers are referred for comprehensive treatment of specific subjects. This first report focuses mainly on anadromous salmon and steelhead (primarily through 1994) but the authors intend to expand the scope of future issues to include resident species. This is the first of what the authors intend to be an annual report. They welcome constructive suggestions for improvements. This report is a product of the StreamNet (formerly Coordinated Information System and Northwest Environmental Data Base) project which is a part of the Bonneville Power Administration`s program to protect, mitigate, and enhance fish and wildlife affected by the development and operation of hydroelectric facilities on the Columbia River and its tributaries. The project is called for in the Fish and Wildlife Program of the Northwest Power Planning Council. The project`s objective is to promote exchange and dissemination of information in a standardized electronic format throughout the basin. This project is administered by the Pacific States Marine Fisheries Commission with active participation by tribal, state, and federal fish and wildlife agencies.

  10. Evaluation of the pollution and human health risks posed by heavy metals in the atmospheric dust in Ebinur Basin in Northwest China.

    PubMed

    Abuduwailil, Jilili; Zhaoyong, Zhang; Fengqing, Jiang

    2015-09-01

    Recently, a large amount of research assessing pollution levels and the related health risks posed by atmosphere dust has been undertaken worldwide. However, little work has been done in the oases of the arid regions of Northwest China. In this paper, we studied the pollution and health risks over a year of seven heavy metals in the atmospheric dust of Ebinur Basin, a typical oasis in Northwest China. The results showed the following: (1) The annual amount of atmospheric deposition in Ebinur Basin was 298.23 g m(-2) and the average monthly atmospheric deposition was 25.06 g m(-2). The average and maximum values of the seven heavy metals measured were all below the National Soil Environmental Quality Standards (2nd). (2) Heavy metals of Cu, Cr, and As in the atmospheric deposition mainly originated from the natural geological background, while Zn came from human activity. This study also showed that among the seven measured heavy metals, the ratios of the no-pollution status of Pb, Cd, and Hg were higher than those of others with moderate degrees of pollution also accounting for a certain ratio. (3) The carcinogenic risks from As, Cd, and Cr were all lower than the corresponding standard limit values, and these metals are considered not harmful to the health of the basin. However, there is a relatively high risk of exposure for children from hand-to-mouth intake, which is worthy of attention. This research showed that both human activity and natural factors, such as wind and altitude, influenced the heavy metal contents in the atmospheric dust of the study area. Furthermore, recent human activity in the study area had the most negative influence on the accumulation of the heavy metals and the corresponding health risks, especially for Hg, Pb, and Cd, which is worthy of attention. PMID:25956515

  11. A quantitative study of the petroleum generation and migration development in the Tarim Basin, northwest of China

    SciTech Connect

    Jianchang Liu; Leonard, C.; Cao, Song; Tang, Jie

    1996-12-31

    The Tarim Basin is the largest undeveloped petroliferous basin in China. Sediments in the basin range from Precambrian to Tertiary in age and from marine carbonate to non-marine clastic in depositional environment. Investigations indicate that there are potential structural, stratigraphic and unconformity traps for oil and gas in the basin. Applying one and two dimensional basin modelling systems to the well data and cross section, a number of different geologic scenarios such as sedimentary compactions, diagenesis, unconformities, faults, thermal maturation, hydrocarbon generation, expulsion, migration and accumulation are modeled. The modelling results in the basin reveal: (1) there is a vast amount of source rock which is thermally mature or overmatured, (2) there are multiple peaks of hydrocarbon generation and a continuous expulsion process in the basin`s history, (3) the Carboniferous rocks which have undergone severe diagenesis are the major oil-producing rocks in both structural and lithological reservoirs in the Paleozoic strata; while the isolated clastic sediments are the major traps in the younger strata, (4) oil in the stratigraphic reservoirs comes mainly from the adjacent source rocks, and, (5) diagenesis and faulting are the major controlling factors for the hydrocarbon accumulations in the Paleozoic reservoirs.

  12. Relating seasonal dynamics of enhanced vegetation index to the recycling of water in two endorheic river basins in north-west China

    NASA Astrophysics Data System (ADS)

    Matin, M. A.; Bourque, C. P.-A.

    2015-08-01

    This study associates the dynamics of enhanced vegetation index in lowland desert oases to the recycling of water in two endorheic (hydrologically closed) river basins in Gansu Province, north-west China, along a gradient of elevation zones and land cover types. Each river basin was subdivided into four elevation zones representative of (i) oasis plains and foothills, and (ii) low-, (iii) mid-, and (iv) high-mountain elevations. Comparison of monthly vegetation phenology with precipitation and snowmelt dynamics within the same basins over a 10-year period (2000-2009) suggested that the onset of the precipitation season (cumulative % precipitation > 7-8 %) in the mountains, typically in late April to early May, was triggered by the greening of vegetation and increased production of water vapour at the base of the mountains. Seasonal evolution of in-mountain precipitation correlated fairly well with the temporal variation in oasis-vegetation coverage and phenology characterised by monthly enhanced vegetation index, yielding coefficients of determination of 0.65 and 0.85 for the two basins. Convergent cross-mapping of related time series indicated bi-directional causality (feedback) between the two variables. Comparisons between same-zone monthly precipitation amounts and enhanced vegetation index provided weaker correlations. Start of the growing season in the oases was shown to coincide with favourable spring warming and discharge of meltwater from low- to mid-elevations of the Qilian Mountains (zones 1 and 2) in mid-to-late March. In terms of plant requirement for water, mid-seasonal development of oasis vegetation was seen to be controlled to a greater extent by the production of rain in the mountains. Comparison of water volumes associated with in-basin production of rainfall and snowmelt with that associated with evaporation seemed to suggest that about 90 % of the available liquid water (i.e. mostly in the form of direct rainfall and snowmelt in the mountains

  13. A Model for Interpreting 10Be Basin-Wide Erosion Rates in Post-Glacial Environments, Northwest Scotland

    NASA Astrophysics Data System (ADS)

    Fame, M. L.; Owen, L. A.; Balco, G.; Spotila, J. A.

    2015-12-01

    Meaningful interpretation of in-situ cosmogenic 10Be basin-wide erosion rates in slowly eroding postglacial catchments is complicated because 10Be is inherited through shifts between glacial and fluvial regimes and ice shielding prevents 10Be production. Such environments do not attain isotopic and landscape steady state, conditions necessary for the current method of calculating basin-wide erosion rates. We propose an alternate set of assumptions, specific to postglacial regions, which make it possible to calculate basin-wide erosion rates in the post-glacial Highlands of NW Scotland. From 20 Scottish basins basin-wide 10Be concentrations range from 2.129 x 104 to 4.870 x 104 atoms/g qtz. Average 10Be concentrations from shallow till and bank deposits within the basins are 2.856 x 104 atoms/g qtz, similar to the basin-wide concentrations, whereas average bedrock concentrations in the basins are 1.747 x 105 atoms/g qtz. This suggests that during the postglacial time most active sediment is derived from reworked deposits rather then sub-aerially eroded bedrock. Therefore, we make the simplifying assumption that most bedrock erosion occurs during glaciation. A deeply buried till that has experienced no nuclide production since deglaciation has a 10Be concentration of 6.810 x 103 atoms/g qtz and allows us to estimate how much of the 10Be in basin-wide samples was produced since deglaciation. A glacial ice thickness of only 2 m would shield all 10Be production; therefore we assume that no 10Be production occurred during glacial periods and that all production occurs during interglacial periods. Using 100 ka as the approximate duration of a Pleistocene glacial-interglacial cycle, comprised of a 15 ka interglacial period and an 85 ka glacial period, and the aforementioned assumptions we have derived a numerical model to calculate basin-wide glacial erosion rates in NW Scotland.

  14. Depositional environments and source rock investigations of the Oligocene to Middle Miocene deposits in the Ardjuna Basin, offshore Northwest Java, Indonesia

    SciTech Connect

    Wu Chiahsin Charlie.

    1991-01-01

    Investigations of depositional environments, paleogeographic evolution, source rock potential/maturity, and petroleum generation, expulsion, migration and accumulation were performed on the Oligocene to Middle Miocene deposits in the Ardjuna Basin, offshore Northwest Java, using integrated geologic, seismic and geochemical approaches. The Oligocene to Middle Miocene sediments were deposited in a generally transgressive sequence. It is the most prospective stratigraphic unit for petroleum exploration in the Ardjuna Basin. The rocks comprise three Formations: Talang Akar, Baturaja and Cibulakan. Paleogeography of six stages within the study interval, showing the degree of marine transgression were mapped based on integrated biostratigraphic, paleoenvironmental, and seismic-stratigraphic data. The coals and carbonaceous shales deposited in the deltaic and nearshore environment of the Talang Akar Formation are petroleum source rocks for the waxy oils produced in the Ardjuna Basin. The organic matter contains predominantly vitrinite maceral and up to 30% exinite maceral. Source rock temperature, after calibration with vitrinite reflectance, provides an accurate quantitative measurement for predicting the level of thermal maturation. Two geochemical approaches were used and compared in petroleum resource assessment: petroleum yield (S1) method and genetic potential (S2) method. The oil generative kitchen, the Ardjuna depocenter, has the best opportunity for new oil discovery. This model has since been proved by subsequent drilling leading to several oil discoveries in the last two years.

  15. A quantitative study of the petroleum generation and migration development in the Tarim Basin, northwest of China

    SciTech Connect

    Jianchang Liu; Leonard, C. ); Cao, Song; Tang, Jie )

    1996-01-01

    The Tarim Basin is the largest undeveloped petroliferous basin in China. Sediments in the basin range from Precambrian to Tertiary in age and from marine carbonate to non-marine clastic in depositional environment. Investigations indicate that there are potential structural, stratigraphic and unconformity traps for oil and gas in the basin. Applying one and two dimensional basin modelling systems to the well data and cross section, a number of different geologic scenarios such as sedimentary compactions, diagenesis, unconformities, faults, thermal maturation, hydrocarbon generation, expulsion, migration and accumulation are modeled. The modelling results in the basin reveal: (1) there is a vast amount of source rock which is thermally mature or overmatured, (2) there are multiple peaks of hydrocarbon generation and a continuous expulsion process in the basin's history, (3) the Carboniferous rocks which have undergone severe diagenesis are the major oil-producing rocks in both structural and lithological reservoirs in the Paleozoic strata; while the isolated clastic sediments are the major traps in the younger strata, (4) oil in the stratigraphic reservoirs comes mainly from the adjacent source rocks, and, (5) diagenesis and faulting are the major controlling factors for the hydrocarbon accumulations in the Paleozoic reservoirs.

  16. Crustal framework of the northwest Paraná Basin, Brazil: Insights from joint modeling of magnetic and gravity data

    NASA Astrophysics Data System (ADS)

    Curto, Julia B.; Vidotti, Roberta M.; Blakely, Richard J.; Fuck, Reinhardt A.

    2015-08-01

    The Transbrasiliano Lineament (TBL) is a major Proterozoic strike-slip shear zone crossing the Paraná Basin, Brazil, yet the relationship between the TBL and basin structures is poorly understood. Magnetic and gravity data are available from the whole northwestern region of the Paraná Basin and provide insights into crustal partitioning and basement geometry. Joint 2D modeling of these data was performed in three strategic sections of the study area. Two smaller sections were constrained by available borehole data and receiver function analysis. Modeling of these sections facilitated modeling of the third, larger NW-SE section, which crosses the basin in an area with significant lack of data. These three sections together form the basis for a preliminary tectonic model of the northern Paraná Basin. The TBL includes strong N30°E-trending gravity and magnetic gradients represented by the Serra Negra fault zone. This structure separates two crustal tectonic domains, the Paranapanema Block to the east, and the Amazon paleocontinent to the west. The tectonic domain northeast of the fault is represented by the Arenópolis Magmatic Arc. The N60°-70°E-trending General Carneiro fault, also reflected in gravity anomalies, forms another important magnetic contact. Our tectonic model shows a region of crustal thinning between the two fault zones, where structures associated with possible reactivation form small Cretaceous basins. The Baliza fault may accommodate significant vertical displacements of Devonian and Carboniferous sections of the Paraná Basin. The main structures revealed in the sections are associated with grabens and horsts, interpreted as reactivated structures that controlled Paraná Basin sedimentation. The northwestern portion of the basin exhibits basement asymmetry caused by dip- and strike-slip faulting along the TBL.

  17. [Ecology-economy harmonious development based on the ecological services value change in Yanqi Basin, Northwest China].

    PubMed

    Mamat, Zulpiya; Halik, Umut; Aji, Rouzi; Nurmemet, Ilyas; Anwar, Mirigul; Keyimu, Maierdang

    2015-03-01

    In this paper, we used land use/cover ecosystem service value estimation model and ecological economic coordination degree model to analyze the changes of the ecosystem service value by the land use/cover changes during 1985, 1990, 1996, 2000, 2005 and 2011 in Yanqi Basin, Xin-jiang. Then we evaluated the ecology-economy harmony and the regional differences. The results showed that during 1985-2011, there was an increasing trend in the areas of waters, wetland, sand, cultivated land and construction land in Yanqi Basin. In contrast, that of the saline-alkali land, grassland and woodland areas exhibited a decreasing trend. The ecosystem service value in Yanqi Basin during this period presented an increasing trend, among which the waters and cultivated land contributed most to the total value of ecosystem services, while the grassland and the woodland had obviously declined contribution to the total value of ecosystem services. The research showed that the development of ecological economy in the study area was at a low conflict and low coordination level. So, taking reasonable and effective use of the regional waters and soil resources is the key element to maintain the ecosystem service function and sustainable and harmonious development of economy in Yanqi Basin.

  18. Effects of groundwater lateral flow on land surface processes: a case study in Heihe River Basin, north-west of China

    NASA Astrophysics Data System (ADS)

    Xie, Z.; Zeng, Y.; Yu, Y.

    2015-12-01

    As an important component of hydrologic cycle, groundwater is affected by topography, vegetation, climate condition, and anthropogenic activity. Groundwater horizontal convergence and divergence and vertical interaction with soil water result in variations of soil moisture, water and energy exchanges between the land surface and the atmosphere, which ultimately influences climate. In this work, a two-dimensional groundwater lateral flow scheme based on groundwater mass equation, is developed and incorporated into the land surface model CLM4.5 to investigate effects of groundwater lateral flow on land surface processes in a river basin. A 30-year simulation with groundwater lateral flow and a control run without the horizontal movement are conducted over Heihe River Basin, north-west China, from 1979 to 2012 using the developed model. Results show that with groundwater lateral flow, equilibrium distribution of groundwater table shows more spatial variability following topography rather than the water balance between local precipitation and evapotranspiration, and are much closer to well observations especially over middle reaches area. Along with shallower groundwater table over piedmont areas in the middle reaches, increased soil moisture is shown which alleviates the underestimation of CLM4.5 at here. Changes in evapotranspiration are occurred and it is mainly controlled by the variation of local surface soil moisture, since water is the major limitation factor of evapotranspiration over this arid area. Besides, groundwater lateral flow can change the distribution of surface runoff by changing the saturated area fraction of each model grid cell. Energy cycle also responds to the changes of hydrological cycle which redistributes the sensible heat flux and latent heat flux in the entire basin.

  19. Slope-apron deposition in an ordovician arc-related setting: The Vuelta de Las Tolas Member (Suri Formation), Famatina Basin, northwest Argentina

    USGS Publications Warehouse

    Mangano, M.G.; Buatois, L.A.

    1997-01-01

    The Ordovician Suri Formation is part of the infill of the Famatina Basin of northwest Argentina, which formed in an active setting along the western margin of early Paleozoic Gondwana. The lower part of this formation, the Vuelta de Las Tolas Member, records sedimentation on a slope apron formed in an intra-arc basin situated on a flooded continental arc platform. The coincidence of a thick Arenig-Llanvirn sedimentary succession and volcanic-plutonic arc rocks suggests an extensional or transtensional arc setting, and is consistent with evidence of an extensional regime within the volcanic arc in the northern Puna region. The studied stratigraphic sections consist of volcanic rocks and six sedimentary facies. The facies can be clustered into four facies associations. Association 1, composed of facies A (laminated siltstones and mudstones) and B (massive mudstones and siltstones), is interpreted to have accumulated from silty-muddy high-and low-density turbidity currents and highly fluid, silty debris flows, with subsequent reworking by bottom currents, and to a lesser extent, hemipelagic suspension in an open-slope setting. Facies association 2 is dominated by facies C (current-rippled siltstones) strata. These deposits are interpreted to record overbank sedimentation from fine-grained turbidity currents. Facies E (matrix-supported volcanic breccias) interbedded with andesitic lava units comprises facies association 3. Deposition was contemporaneous with subaqueous volcanic activity, and accumulated from cohesive debris flows in a coarse-grained wedge at the base of slope. Facies association 4 is typified by facies D (vitric fine-grained sandstones and siltstones) and F (channelized and graded volcanic conglomerates and breccias) deposits. These strata commonly display thinning-and fining-upward trends, indicating sedimentation from highly-concentrated volcaniclastic turbidity currents in a channelized system. The general characteristics of these deposits of fresh

  20. Geology and coal resources of Zonguldak basin (Northwest Turkey) as a potential source for coal bed methane

    SciTech Connect

    Yalcin, M.N. )

    1991-03-01

    The Carboniferous clastic sequence of Zonguldak basin contains several coal seams that have been mined since 1848 by underground methods. Coal seams are located in a Namurian to Westfalian D progradational delta and fluid plain sequence that is approximately 3,500 m thick. These units are affected by Hercynian orogenic movements. Related tectonism and uplift led to a widespread erosion. Consequently, younger units, mainly Cretaceous shallow-marine carbonates, rest unconformably on different sections of the Carboniferous strata. There exist up to 8 coal seams in Namurian, 20 to 26 in Westfalian A, and up to 8 coal seams in Westfalian B, C, and D. The average combined thickness values are 8 m, 34 m, and 7 m, respectively. However, due to the lateral changes in seam thickness and due to the erosion, both the number and combined thickness of coal seams may change remarkably. Majority of the coals in the exploitation area are of highly volatile C to A bituminous rank. Vitrinite reflectance values range from 0.6 to 1.2% (R{sub 0} mean). Methane content of some coal seams is determined by desorption data which indicate a methane content of 5 to 16 m{sup 3} per ton of coal. In addition to classical methods, data from some deep wells have been used to determine the thermal history by the method of basin modeling. Amount of gas generated in coals is then computed with the help of a kinetic approach. Furthermore, timing of gas generation has also been determined, which enabled consideration of migrational and diffusional gas losses. Data from coal geology, geochemistry, and modeling are combined to evaluate the coal bed methane potential of the basin in an integrated and quantitative manner.

  1. Evaluation of ecosystem services: A case study in the middle reach of the Heihe River Basin, Northwest China

    NASA Astrophysics Data System (ADS)

    Li, Hongji; Li, Zhihui; Li, Zhaohua; Yu, Jing; Liu, Bing

    Ecosystem services evaluation aims at understanding the status of ecosystem services on different spatial and temporal scale. In this paper, we selected the middle reach of the Heihe River Basin (HRB), which is the second largest inland river basin in China, as one of the typical area to estimate the ecosystem services values (ESVs) corresponding to the land use changes. Based on the land use data and ecosystem service value coefficients, the total ecosystem services values (TESVs) of the middle reach of the HBR are quantitatively calculated, which were 9.244 × 108, 9.099 × 108, 9.131 × 108 and 9.146 × 108 USD in 1988, 2000, 2005 and 2008 respectively. During 1988-2008, the decrease of grassland, forest land, water area and unused land contributed 148.94%, 57.85%, 87.87% and 16.42% respectively to the net loss of TESVs, while the dramatic increase of cultivated land improved the TESVs with contribution of -211.08% to the net loss of TESVs. Expansion of cultivated land, which especially caused the loss of grassland and forest land, directly exerted negative impacts on the provision of ecosystem services in the study area. The findings of this research indicated that land use change was an important form of human activities, which had a strong impact on ecosystem services.

  2. Ichnological constraints on the depositional environment of the Sawahlunto Formation, Kandi, northwest Ombilin Basin, west Sumatra, Indonesia

    NASA Astrophysics Data System (ADS)

    Zonneveld, J.-P.; Zaim, Y.; Rizal, Y.; Ciochon, R. L.; Bettis, E. A.; Aswan; Gunnell, G. F.

    2012-02-01

    A low diversity trace fossil assemblage is described from the Oligocene Sawahlunto Formation near Kandi, in the northwestern part of the Ombilin Basin in western Sumatra, Indonesia. This trace fossil assemblage includes six ichnogenera attributed to invertebrate infaunal and epifaunal activities ( Arenicolites, Diplocraterion, Planolites, Monocraterion/ Skolithos and Coenobichnus) and two ichnotaxa attributed to vertebrate activity (avian footprints: two species of Aquatilavipes). Arenicolites, Diplocraterion and Monocraterion/ Skolithos record the suspension feeding activities of either arthropods (most likely amphipods) or vermiform organisms. Planolites reflects the presence of an infaunal deposit feeder. Coenobichnus records the walking activities of hermit crabs. Both the Coenobichnus and the avian footprints record the surficial detritus scavenging of epifaunal organisms within a subaerial setting. These traces occur within a fine-grained sandstone succession characterized by planar laminae and low-relief, asymmetrical, commonly mud-draped (locally bidirectional) ripples. The presence of traces attributable to suspension feeders implies deposition in a subaqueous setting. Their occurrence (particularly the presence of Arenicolites and Diplocraterion) in a sandstone bed characterized by mud-draped and bidirectional ripples implies emplacement in a tidally-influenced marine to marginal marine setting. Co-occurrence of these traces with well-preserved avian footprints ( Aquatilavipes) further implies periodic subaerial exposure. Thus, it is most likely that the Sawahlunto Formation near Kandi records deposition within an intertidal flat setting. Definitive evidence of marine influences in the Oligocene interval of the Ombilin Basin implies a more complex tectono-stratigraphic history than has previously been implied.

  3. Rates of landscape change in discontinuous permafrost terrain inferred from Goose Lake sediments, Scotty Creek Basin, Northwest Territories, Canada

    NASA Astrophysics Data System (ADS)

    Cockburn, J.; Baltzer, J.; Quinton, W. L.

    2012-12-01

    Changes to the Taiga Plain regions of the world due to recent permafrost thaw and a general warming trend has significant impacts on hydrology, ecology and carbon sequestration in these regions. Furthermore, the rates of these changes may prove to be positive feedbacks within the cryosphere. The recent sedimentary record from Goose Lake, NWT (61° 18' N, 121° 18' W) reveals changes in lake and adjacent landscape productivity, likely coincident with degrading permafrost through the late Holocene and noticeable shifts within the last half of the 20th century. Using short-cores retrieved in August 2012, this study presents preliminary models of late Holocene landscape changes. Shifts in the rates of change are due to recent thaw as evidenced by the sedimentary record and supported through process work completed in the region. Goose Lake is situated in the Taiga Plains, approximately 50 km south of Fort Simpson, in the lower Liard River basin. This small, lake (~2.5 m deep, 200 ha) in the Scotty Creek watershed headwaters is primarily fed through small fens. The Scotty Creek basin has had over a decade of permafrost and peatland hydrological monitoring (i.e., Quinton et al., 2009). As well, the Scotty Creek basin is the location of ongoing peatland ecological and hydrological monitoring programs. The monitoring work suggests that there is a cycle of bog - fen - plateau (ice-rich) landscape changes and that perhaps the rate of these cycles may be increasing as permafrost degradation increases. The lake sediment work aims to estimate the rates of these cycles through the late Holocene and potentially link to larger scale models of change within the Taiga Plains. A shift in cycling would have substantial impacts on carbon storage, ecosystem diversity and potentially change the overall hydrology of this peatland area. If Goose Lake is indicative of other small lakes in the Taiga Plains, combined with the hydrological and ecological observations, this system will be a

  4. Groundwater quality and its suitability for drinking and agricultural use in the Yanqi Basin of Xinjiang Province, Northwest China.

    PubMed

    Wang, Shuixian

    2013-09-01

    The Yanqi Basin in Xinjiang Province is an important agricultural area with a high population density. The extensive agricultural activities in the Yanqi Basin started in the 1950s with flood irrigation techniques. Since then, the groundwater table was raised because of the absence of an efficient drainage system. This obstacle is a crucial factor that restricts sustainable socioeconomic development. Hydrochemical investigations were conducted in the Yanqi Basin, Northwestern China, to determine the chemical composition of groundwater. Sixty groundwater samples were collected from different wells to monitor the water chemistry of various ions. The results of the chemical analysis indicate that the groundwater in the area is generally neutral to slightly alkaline and predominantly contains Na(+) and Ca(2+) cations as well as HCO3(-) and SO4 (2+) anions. High positive correlations between HCO3 (-)-Mg(2+) + Ca(2+), SO 4 (2-)-Mg(2+), SO4 (2-)-Na(+) + K(+), and Cl(-)-Na(+) + K(+) were obtained. The total dissolved solids (TDS) mainly depend on the concentration of major ions such as HCO3(-), SO4 (2-), Cl(-), Ca(2+), Mg(2+), and Na(+) + K(+). The dominant hydrochemical facies for groundwater are Ca(2+)-Mg(2+)-HCO3(-), Mg(2+)-Ca(2+)-SO4 (2-)-Cl(-), Na(+)-K(+)-Cl(-)-SO4 (2-), and Na(+)-K(+)-Mg(2+)-Cl(-)-HCO3(-) types. The hydrochemical processes are the main factors that determine the water quality of the groundwater system. These processes include silicate mineral weathering, dissolution, ion exchange, and, to a lesser extent, evaporation, which seem to be more pronounced downgradient of the flow system. The saturation index (SI), which is calculated according to the ionic ratio plot, indicates that the gypsum-halite dissolution reactions occur during a certain degree of rock weathering. SI also indicates that evaporation is the dominant factor that determines the major ionic composition in the study area. The assessment results of the water samples using various methods

  5. Groundwater quality and its suitability for drinking and agricultural use in the Yanqi Basin of Xinjiang Province, Northwest China.

    PubMed

    Wang, Shuixian

    2013-09-01

    The Yanqi Basin in Xinjiang Province is an important agricultural area with a high population density. The extensive agricultural activities in the Yanqi Basin started in the 1950s with flood irrigation techniques. Since then, the groundwater table was raised because of the absence of an efficient drainage system. This obstacle is a crucial factor that restricts sustainable socioeconomic development. Hydrochemical investigations were conducted in the Yanqi Basin, Northwestern China, to determine the chemical composition of groundwater. Sixty groundwater samples were collected from different wells to monitor the water chemistry of various ions. The results of the chemical analysis indicate that the groundwater in the area is generally neutral to slightly alkaline and predominantly contains Na(+) and Ca(2+) cations as well as HCO3(-) and SO4 (2+) anions. High positive correlations between HCO3 (-)-Mg(2+) + Ca(2+), SO 4 (2-)-Mg(2+), SO4 (2-)-Na(+) + K(+), and Cl(-)-Na(+) + K(+) were obtained. The total dissolved solids (TDS) mainly depend on the concentration of major ions such as HCO3(-), SO4 (2-), Cl(-), Ca(2+), Mg(2+), and Na(+) + K(+). The dominant hydrochemical facies for groundwater are Ca(2+)-Mg(2+)-HCO3(-), Mg(2+)-Ca(2+)-SO4 (2-)-Cl(-), Na(+)-K(+)-Cl(-)-SO4 (2-), and Na(+)-K(+)-Mg(2+)-Cl(-)-HCO3(-) types. The hydrochemical processes are the main factors that determine the water quality of the groundwater system. These processes include silicate mineral weathering, dissolution, ion exchange, and, to a lesser extent, evaporation, which seem to be more pronounced downgradient of the flow system. The saturation index (SI), which is calculated according to the ionic ratio plot, indicates that the gypsum-halite dissolution reactions occur during a certain degree of rock weathering. SI also indicates that evaporation is the dominant factor that determines the major ionic composition in the study area. The assessment results of the water samples using various methods

  6. The depositional setting of the Late Quaternary sedimentary fill in southern Bannu basin, Northwest Himalayan fold and thrust belt, Pakistan.

    PubMed

    Farid, Asam; Khalid, Perveiz; Jadoon, Khan Zaib; Jouini, Mohammed Soufiane

    2014-10-01

    Geostatistical variogram and inversion techniques combined with modern visualization tools have made it possible to re-model one-dimensional electrical resistivity data into two-dimensional (2D) models of the near subsurface. The resultant models are capable of extending the original interpretation of the data to depict alluvium layers as individual lithological units within the 2D space. By tuning the variogram parameters used in this approach, it is then possible to visualize individual lithofacies and geomorphological features for these lithologic units. The study re-examines an electrical resistivity dataset collected as part of a groundwater study in an area of the Bannu basin in Pakistan. Additional lithological logs from boreholes throughout the area have been combined with the existing resistivity data for calibration. Tectonic activity during the Himalayan orogeny uplifted and generated significant faulting in the rocks resulting in the formation of a depression which subsequently has been filled with clay-silt and dirty sand facies typical of lacustrine and flood plain environments. Streams arising from adjacent mountains have reworked these facies which have been eroded and replaced by gravel-sand facies along channels. It is concluded that the sediments have been deposited as prograding fan shaped bodies, flood plain, and lacustrine deposits. Clay-silt facies mark the locations of paleo depressions or lake environments, which have changed position over time due to local tectonic activity and sedimentation. The Lakki plain alluvial system has thus formed as a result of local tectonic activity with fluvial erosion and deposition characterized by coarse sediments with high electrical resistivities near the mountain ranges and fine sediments with medium to low electrical resistivities towards the basin center.

  7. Responses of shelterbelt stand transpiration to drought and groundwater variations in an arid inland river basin of Northwest China

    NASA Astrophysics Data System (ADS)

    Shen, Qin; Gao, Guangyao; Fu, Bojie; Lü, Yihe

    2015-12-01

    Plant water use characteristics and transpiration responses under dry conditions are considered essential for effective and sustainable ecosystem management in arid areas. This study was conducted to evaluate the response of shelterbelt stand transpiration to precipitation, soil drought and groundwater variations in an oasis-desert ecotone in the middle of the Heihe River Basin, China. Sap flow was measured in eight Gansu Poplar trees (Populus Gansuensis) with different diameter at breast height over three consecutive growing seasons (2012-2014). The groundwater evapotranspiration via plant use was estimated by the White method with diurnal water table fluctuations. The results showed that precipitation increased the stand transpiration but not statistically significant (paired t-test, p > 0.05). The recharge of soil water by irrigation caused stand transpiration acceleration significantly (t-test, p < 0.05). Stand transpiration and canopy conductance increased by 27% and 31%, respectively, when soil water conditions changed from dry to wet. Canopy conductance decreased logarithmically with vapor pressure deficit, while there was no apparent relationship between canopy conductance and solar radiation. The sensitivity of canopy conductance to vapor pressure deficit decreased under dry soil conditions. Groundwater evapotranspiration (0.6-7.1 mm day-1) was linearly correlated with stand transpiration (1.1-6.5 mm day-1) (R2 = 0.71), and these two variables had similar variability. During the drought period, approximately 80% of total stand transpiration came from groundwater evapotranspiration. This study highlighted the critical role of irrigation and groundwater for shelterbelt, and might provide the basis for the development of water requirement schemes for shelterbelt growth in arid inland river basins.

  8. The depositional setting of the Late Quaternary sedimentary fill in southern Bannu basin, Northwest Himalayan fold and thrust belt, Pakistan.

    PubMed

    Farid, Asam; Khalid, Perveiz; Jadoon, Khan Zaib; Jouini, Mohammed Soufiane

    2014-10-01

    Geostatistical variogram and inversion techniques combined with modern visualization tools have made it possible to re-model one-dimensional electrical resistivity data into two-dimensional (2D) models of the near subsurface. The resultant models are capable of extending the original interpretation of the data to depict alluvium layers as individual lithological units within the 2D space. By tuning the variogram parameters used in this approach, it is then possible to visualize individual lithofacies and geomorphological features for these lithologic units. The study re-examines an electrical resistivity dataset collected as part of a groundwater study in an area of the Bannu basin in Pakistan. Additional lithological logs from boreholes throughout the area have been combined with the existing resistivity data for calibration. Tectonic activity during the Himalayan orogeny uplifted and generated significant faulting in the rocks resulting in the formation of a depression which subsequently has been filled with clay-silt and dirty sand facies typical of lacustrine and flood plain environments. Streams arising from adjacent mountains have reworked these facies which have been eroded and replaced by gravel-sand facies along channels. It is concluded that the sediments have been deposited as prograding fan shaped bodies, flood plain, and lacustrine deposits. Clay-silt facies mark the locations of paleo depressions or lake environments, which have changed position over time due to local tectonic activity and sedimentation. The Lakki plain alluvial system has thus formed as a result of local tectonic activity with fluvial erosion and deposition characterized by coarse sediments with high electrical resistivities near the mountain ranges and fine sediments with medium to low electrical resistivities towards the basin center. PMID:25004850

  9. [Relationships among leaf traits and their expression in different vegetation zones in Yanhe River basin, Northwest China].

    PubMed

    Guo, Ru; Wen, Zhong-ming; Wang, Hong-xia; Qi, De-hui

    2015-12-01

    This article selected zonal plant communities as the research objects in different vegetation zones in Yanhe River basin. We measured six leaf traits of the dominant species and main accompanying species in each community, and then analyzed the relationships and their changes along with environmental gradients between these traits in order to understand the plant adaptation strategies to the environment changes. The results showed that the specific leaf area was significantly negatively correlated to leaf tissue density, area-based leaf nitrogen and phosphorus concentrations, and significantly positively correlated to mass-based leaf phosphorus concentration. Both the scaling relationships among these traits and plant life strategies were different among the three vegetation zones, the scaling-dependent relationship between leaf tissue density and specific leaf area was stronger in steppe and forest-steppe zones than in forest zone, but the correlations among area-based leaf nitrogen/phosphorus concentrations and specific leaf area and leaf tissue density were more significant in forest zone than in steppe zone. In the arid grassland and forest-steppe zone, plants give priority to defensive and stress resistance strategies, and in relatively moist nutrient-rich forest zone, plants give priority to fast growth and resource optimization allocation strategies. PMID:27111998

  10. Paleoenvironmental reconstruction based on palynofacies analyses of the Cansona Formation (Late Cretaceous), Sinú-San Jacinto Basin, northwest Colombia

    NASA Astrophysics Data System (ADS)

    Juliao-Lemus, Tatiana; Carvalho, Marcelo de Araujo; Torres, Diego; Plata, Angelo; Parra, Carlos

    2016-08-01

    To reconstruct the paleoenvironments of the Cansona Formation, a Cretaceous succession in Colombia that has controversial paleoenvironmental interpretation, occasionally deep marine and occasionally shallow marine, palynofacies analyses were conducted on 93 samples from four sections of the Sinú San Jacinto Basin in the north, midwest, and southwest sectors. For the palynofacies analyses, the kerogen categories were counted and subjected to cluster analyses. Four palynofacies associations were revealed for the four sections: Palynofacies Association I (PA I), which consisted of microforaminiferal linings, scolecodonts, dinoflagellate cysts, pollen grains, and fungi hyphae; PA II, which consisted of phytoclast translucent non-biostructured and biostructured, opaque phytoclasts (equidimensional and lath shaped); PA III, which consisted of pseudoamorphous particles, cuticles, resin, and fungal spores; and PA IV, which consisted of fluorescent and non-fluorescent amorphous organic matter and the fresh-water algae Botryococcus. In contrast to early studies that suggested a generalization of the depositional environment for the Cansona Formation (deep or shallow conditions), this study suggests that the formation reflects conspicuous stratigraphic and lateral changes and hence different depositional environments. The Cerro Cansona (CC4 section) and Chalán (AP section) areas are a more marine proximal settings (Early Campanian-Maastrichtian), and there is an intermediate setting for the Lorica area (SC section) and deeper conditions for the Montería area (CP2 section).

  11. Paleomagnetism and anisotropy of magnetic susceptibility of Eocene and Miocene sediments in the Qaidam Basin, Northwest China: Implication for the Cenozoic tectonic transition and development of the northern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Yu, X.; Guo, Z.; Huang, B.; Yin, A.; Guan, S.; Zhou, S.; Qiao, Q.; Cheng, F.; Cheng, X.; Zhang, T.

    2013-12-01

    Paleomagnetism and AMS (Anisotropy of Magnetic Susceptibility) results are reported from the middle to late Eocene Xiaganchaigou Formation and the early to middle Miocene Xiayoushashan Formation sediments at eight locations (Xichagou, Gansen, Eboliang, Heishiqiu, Luluohe, Kushuiquan, Hong Shan and Gahai), covering most outcrop regions of these two formations within the Qaidam Basin, Northwest China. These paleomagnetic data indicate that the Qaidam basin has not undergone wholesale tectonic vertical axis rotation relative to Eurasia and North China since at least middle and late Eocene. Local clockwise rotation only took place at some special locations such as Gahai. According to AMS results, 12 of 16 AMS ellipsoids belong to embryonic deformation magnetic fabric, which can be applied to reconstruct tectonic strain. Two epochs of compressive strain have been identified in the Qaidam basin during the Cenozoic: an early N-S strain no later than the Oligocene and a late NE-SW strain mainly after the early to middle Miocene. Further analysis shows that the early N-S compression in northern Qaidam basin is much more intense than that in western Qaidam basin, while the late NE-SW compression, which dominates the NW-SE-trending folds in the modern Qaidam basin, is more intense in western Qaidam basin than that in northern Qaidam basin. The stress concentration transition provides a reasonable explanation of the southeastwards migration of the deposition center in the Qaidam basin during the Cenozoic. The uniform paleomagnetic and AMS results at different localities reveal that the Qaidam basin is a relatively rigid plate, obviously different from the surrounding regions. Moreover, the appearance of E-component stress may be in close relationship with the beginning of the left-lateral Kunlun Fault or the eastwards channel flow south to the Kunlun Fault, implying that the south side of the Kunlun Fault is the active side.

  12. Soil carbon content and CO2 flux along a hydrologic gradient in a High-Arctic tundra lake basin, Northwest Greenland

    NASA Astrophysics Data System (ADS)

    McKnight, J.; Klein, E. S.; Welker, J. M.; Schaeffer, S. M.; Franklin, M.

    2015-12-01

    High Arctic landscapes are composed of watershed basins that vary in size and ecohydrology, but typically have a plant community complex that ranges from dry tundra to moist tundra to wet sedge systems along water body shorelines. The spatial extent of these plant communities reflects mean annual soil moisture and temperature, and is vulnerable to changes in climate conditions. Soil moisture and temperature significantly influence organic matter microbial activity and decomposition, and can affect the fate of soil carbon in tundra soils. Consequently, due to the unique soil carbon differences between tundra plant communities, shifts in their spatial extent may drive future High Arctic biosphere-atmosphere interactions. Understanding this terrestrial-atmosphere trace gas feedback, however, requires quantification of the rates and patterns of CO2 exchange along soil moisture gradients and the associated soil properties. In summer of 2015, soil CO2 flux rate, soil moisture and temperature were measured along a soil moisture gradient spanning three vegetation zones (dry tundra, wet tundra, and wet grassland) in a snow melt-fed lake basin near Thule Greenland. Mean soil temperature during the 2015 growing season was greater in dry tundra than in wet tundra and wet grassland (13.0 ± 1.2, 7.8 ± 0.8, and 5.5 ± 0.9°C, respectively). Mean volumetric soil moisture differed among all three vegetation zones where the soil moisture gradient ranged from 9 % (dry tundra) to 34 % (wet tundra) to 51 % (wet grassland). Mean soil CO2 flux was significantly greater in the wet grassland (1.7 ± 0.1 μmol m-2 s-1) compared to wet tundra (0.9 ± 0.2 μmol m-2 s-1) and dry tundra (1.2 ± 0.2 μmol m-2 s-1). Soil CO2 flux increased and decreased with seasonal warming and cooling of soil temperature. Although soil temperature was an important seasonal driver of soil CO2 flux rates, differences in mean seasonal soil CO2 flux rates among vegetation zones appeared to be a function of the

  13. Lower Eocene alluvial paleosols (Willwood Formation, Northwest Wyoming, U.S.A.) and their significance for paleoecology, paleoclimatology, and basin analysis

    USGS Publications Warehouse

    Bown, T.M.; Kraus, M.J.

    1981-01-01

    The lower Eocene Willwood Formation of northwest Wyoming is a 700 m thick accumulation of alluvial floodplain and channel mudstones and sandstones, nearly all of which show paleopedogenic modifications. Pedogenesis of Willwood sandstones is indicated by taproot and vertebrate and invertebrate bioturbation, early local cementation by calcium carbonate, and thin illuviation cutans on clastic grains. Pedogenesis in Willwood mudstones is indicated by plant bioturbation, insect and other invertebrate burrow casts and lebensspuren; free iron, aluminum, and manganese mobilization, including hydromorphic gleying; sesquioxide and calcareous glaebule formation in lower parts of the solum; presence of clay-rich and organic carbon-rich zones; and well differentiated epipedons and albic and spodic horizons. Probable A horizons are also locally well developed. Occurrence of variegated paleosol units in thick floodplain mudstone deposits and their association with thin, lenticular, and unconnected fluvial sandstones in the Willwood Formation of the central and southeast Bighorn Basin suggest that these soils formed during times of rapid sediment accumulation. The tabular geometry and lateral persistence of soil units as well as the absence of catenization indicate that Willwood floodplains were broad and essentially featureless. All Willwood paleosols were developed on alluvial parent materials and are complex in that B horizons of younger paleosols were commonly superimposed upon and mask properties of suspected A and B horizons of the next older paleosols. The soils appear to be wet varieties of the Spodosol and Entisol groups (aquods and ferrods, and aquents, respectively), though thick, superposed and less mottled red, purple, and yellow paleosols resemble some ultisols. Most Willwood paleosols resemble warm temperate to subtropical alluvial soils that form today under alternating wet and dry conditions and (or) fluctuating water tables. The up-section decrease in frequency

  14. Morphologies and depositional/erosional controls on evolution of Pliocene-Pleistocene carbonate platforms: Northern Carnarvon Basin, Northwest Shelf of Australia

    NASA Astrophysics Data System (ADS)

    Goktas, P.; Austin, J. A.; Fulthorpe, C. S.; Gallagher, S. J.

    2016-08-01

    The detailed morphologies, evolution and termination of latest Neogene tropical carbonate platforms in the Northern Carnarvon Basin (NCB), on the passive margin of the Northwest Shelf (NWS) of Australia, defined based upon mapping using 3D seismic images, reveal the history of local/regional oceanographic processes, fluctuations in relative sea-level and changing climate. Cool-water carbonate deposition, dominant during the early-middle Miocene, was followed by a siliciclastic influx, which prograded across the NWS beginning in the late-middle Miocene, during a period of long-term global sea-level fall. The resulting prograding clinoform sets, interpreted as delta lobes, created relict topographic highs following Pliocene termination of the siliciclastic influx. These highs constituted multiple favorable shallow-water environments for subsequent photozoan carbonate production. Resultant platform carbonate development, in addition to being a response to cessation of siliciclastic influx and the existence of suitable shallow-water substrate, was also influenced by development of the warm-water Leeuwin Current (LC), flowing southwestward along this margin. Four flat-topped platforms are mapped; each platform top is a sequence boundary defined by reflection onlap above and truncation below. Successive platforms migrated southwestward through time, along margin strike. All platforms exhibit predominantly progradational seismic geometries. Mapped tops are ≥10 km wide. Seismic evidence of karst on three of four platform tops, e.g., v-shaped troughs up to 50 m deep and ~1 km wide, and broader basins with areas up to 20 km2, suggests episodic subaerial exposure that may have contributed to platform demise. Platform 4, the most recent, is unique in having interpreted biohermal build-ups superimposed on the progradational platform base. The base of these interpreted patch reefs now lies at a water depth of ~153 m; therefore, we suggest that these reefs developed post

  15. Microfacies and depositional environments of the Late Ordovician Lianglitage Formation at the Tazhong Uplift in the Tarim Basin of Northwest China

    NASA Astrophysics Data System (ADS)

    Gao, Da; Lin, Changsong; Yang, Haijun; Zuo, Fanfan; Cai, Zhenzhong; Zhang, Lijuan; Liu, Jingyan; Li, Hong

    2014-04-01

    The Late Ordovician Lianglitage Formation comprises 13 microfacies (Mf1-Mf13) that were deposited on a carbonate platform at the Tazhong Uplift of the Tarim Basin in Northwest China. Each type of microfacies indicates a specific depositional environment with a certain level of wave energy. Four primary groups of microfacies associations (MA1-MA4) were determined. These associations represent different depositional facies, including reef-shoal facies in the platform margin (MA1), carbonate sand shoal facies (MA2) and oncoid shoal (MA3) on open platforms, and lagoon and tidal flat facies (MA4) in the platform interior. Each microfacies association was generated in a fourth-order sedimentary sequence developing within third-order sequences (SQ1, SQ2, and SQ3, from bottom to top), showing a shallowing-upward trend. High-frequency sequences and facies correlation between wells suggests that the reef-shoal facies more successively developed in the southeastern part of the platform margin, and high-energy microfacies were more strictly confined by the top boundary of fourth-order sequences in the northwestern part of the platform. The highstand systems tract (HST) of the SQ2 is characterized by reef-shoals that developed along the platform margin and tidal flats and lagoons that developed in the platform interior, while the SQ3 is characterized by the oncoid shoal facies that generally developed on the uplift due to a regionally extensive transgression that occurred during the latter part of the Late Ordovician. The results of this study can be used for investigating the development and distribution of potential reservoirs; the reservoirs in southeastern part of the platform margin may be of premium quality because the high-energy microfacies were best preserved there.

  16. Magnetotelluric imaging of a fossil paleozoic intraoceanic subduction zone in western Junggar, NW China

    NASA Astrophysics Data System (ADS)

    Xu, Yixian; Yang, Bo; Zhang, Sheng; Liu, Ying; Zhu, Lupei; Huang, Rong; Chen, Chao; Li, Yongtao; Luo, Yinhe

    2016-06-01

    The fate of subducted oceanic slabs can provide important clues to plate reconstruction through Earth history. Since oceanic slabs in continental collision zones are typically not well preserved, ancient subduction zones have rarely been imaged by geophysical techniques. Here we present an exception from the Darbut belt in the Junggar accretionary collage in the southern Altaids of Asia. We deployed a 182 km long magnetotelluric (MT) profile including 60 broadband sounding sites across the belt. Quality off-diagonal impedances were inverted by a three-dimensional scheme to image resistivities beneath the profile. The resistivity model along with MT impedance phase ellipses and induction vectors were tested and interpreted in detail. Combining geological and geophysical observations, mineral physical experiment, and geodynamic modeling results, the MT transect suggests a fossil intraoceanic subduction zone during the Late Paleozoic in the western Junggar that has been well preserved due to lack of significant subsequent tecto-thermal events.

  17. The Disastrous Effects of Salt Dust Deposition on Cotton Leaf Photosynthesis and the Cell Physiological Properties in the Ebinur Basin in Northwest China

    PubMed Central

    Abuduwaili, Jilili; Zhaoyong, Zhang; Feng qing, Jiang; Dong wei, Liu

    2015-01-01

    Salt dust in rump lake areas in arid regions has long been considered an extreme stressor for both native plants and crops. In recent years, research on the harmful effects of salt dust on native plants has been published by many scholars, but the effect on crops has been little studied. In this work, in order to determine the impact of salt dust storms on cotton, we simulated salt dust exposure of cotton leaves in Ebinur Basin in Northwest China, and measured the particle sizes and salt ions in the dust, and the photosynthesis, the structure and the cell physiological properties of the cotton leaves. (1) Analysis found that the salt ions and particle sizes in the salt dust used in the experiments were consistent with the natural salt dust and modeled the salt dust deposition on cotton leaves in this region. (2) The main salt cations on the surface and inside the cotton leaves were Na+, Ca2+, Cl- and SO42-, while the amounts of CO3- and HCO3- were low. From the analysis, we can order the quantity of the salt cations and anions ions present on the surface and inside the cotton leaves as Na+>Ca2+>Mg2+>K+ and Cl->SO42->HCO3->CO3-, respectively. Furthermore, the five salt dust treatment groups in terms of the total salt ions on both the surface and inside the cotton leaves were A(500g.m-2)>B(400g.m-2)>C(300g.m-2)>D(200g.m-2)>E(100g.m-2)>F(0g.m-2). (3)The salt dust that landed on the surface of the cotton leaves can significantly influence the photosynthetic traits of Pn, PE, Ci, Ti, Gs, Tr, WUE, Ls, φ, Amax, k and Rady of the cotton leaves. (4)Salt dust can significantly damage the physiological functions of the cotton leaves, resulting in a decrease in leaf chlorophyll and carotenoid content, and increasing cytoplasmic membrane permeability and malondialdehyde (MDA) content by increasing the soluble sugar and proline to adjust for the loss of the cell cytosol. This increases the activity of antioxidant enzymes to eliminate harmful materials, such as the intracellular

  18. The disastrous effects of salt dust deposition on cotton leaf photosynthesis and the cell physiological properties in the Ebinur Basin in Northwest China.

    PubMed

    Abuduwaili, Jilili; Zhaoyong, Zhang; Feng qing, Jiang; Dong wei, Liu

    2015-01-01

    Salt dust in rump lake areas in arid regions has long been considered an extreme stressor for both native plants and crops. In recent years, research on the harmful effects of salt dust on native plants has been published by many scholars, but the effect on crops has been little studied. In this work, in order to determine the impact of salt dust storms on cotton, we simulated salt dust exposure of cotton leaves in Ebinur Basin in Northwest China, and measured the particle sizes and salt ions in the dust, and the photosynthesis, the structure and the cell physiological properties of the cotton leaves. (1) Analysis found that the salt ions and particle sizes in the salt dust used in the experiments were consistent with the natural salt dust and modeled the salt dust deposition on cotton leaves in this region. (2) The main salt cations on the surface and inside the cotton leaves were Na+, Ca2+, Cl- and SO42-, while the amounts of CO3- and HCO3- were low. From the analysis, we can order the quantity of the salt cations and anions ions present on the surface and inside the cotton leaves as Na+>Ca2+>Mg2+>K+ and Cl->SO42->HCO3->CO3-, respectively. Furthermore, the five salt dust treatment groups in terms of the total salt ions on both the surface and inside the cotton leaves were A(500g.m-2)>B(400g.m-2)>C(300g.m-2)>D(200g.m-2)>E(100g.m-2)>F(0g.m-2). (3)The salt dust that landed on the surface of the cotton leaves can significantly influence the photosynthetic traits of Pn, PE, Ci, Ti, Gs, Tr, WUE, Ls, φ, Amax, k and Rady of the cotton leaves. (4)Salt dust can significantly damage the physiological functions of the cotton leaves, resulting in a decrease in leaf chlorophyll and carotenoid content, and increasing cytoplasmic membrane permeability and malondialdehyde (MDA) content by increasing the soluble sugar and proline to adjust for the loss of the cell cytosol. This increases the activity of antioxidant enzymes to eliminate harmful materials, such as the intracellular

  19. U-Pb detrital zircon ages to determine the provenance signature of late Quaternary paleo-channel systems in the western Indo-Gangetic basin, northwest India

    NASA Astrophysics Data System (ADS)

    Singh, A.; Carter, A.; Gupta, S.; Sinha, R.; Murray, A. S.; Buylaert, J.; Thomsen, K.; Jain, M.; Paul, D.

    2011-12-01

    An extensive set of paleo-river channels are present in the shallow subsurface of the alluvial plains of the western Indo-Gangetic basin in northwest India as evidenced by the analysis of satellite imagery. There has been considerable interest in paleochannels in the doab between the present-day courses of the Sutlej and Yamuna rivers in particular because of the hypothesized relationship between the distribution of Harappan settlements and paleo-river courses. Specifically, the Ghaggar-Hakra paleo-channel has been the focus of attention because of the occurrence of archaeological Harappan sites along its course. Several studies link the end of the Harappan urban phase ~3500 BP to paleo-river drying or drainage diversion. However, no detailed scientific study has been done to establish the sub-surface stratigraphy and/or the provenance of alluvial sediments of the Ghaggar-Hakra paleo-channel. Some of the major questions are: (1) What is the provenance of the sediments that form the paleo-channels?; (2) Do they represent major Himalayan-sourced paleo-rivers or smaller rivers derived from the frontal Himalayan ranges? We investigated the provenance of river sediments retrieved through core-drilling, down to ~50 m depth, along three transects across the paleo-valleys on the Ghaggar and Sutlej plains. Drill core litho-stratigraphy shows ~20-25 m thick micaceous coarse- to medium-sand bodies at variable depths below ~10 m. U-Pb detrital zircon ages were determined for the fluvial sand bodies, in five drill-cores, using the LA-ICPMS technique available at University College of London. We selected 3-7 number of samples from each core and performed heavy mineral separation to extract zircon grains, which were then dated by U-Pb technique. Further to establish provenance links we determined the U-Pb ages of detrital zircons from modern river sands along this sector of the Himalayan front, i.e., the major Himalayan rivers such as the modern Sutlej, the Yamuna, and the Ganges

  20. Contrasting styles of mineralization in the Chinese Altai and East Junggar, NW China: implications for the accretionary history of the southern Altaids

    NASA Astrophysics Data System (ADS)

    Wan, Bo; Xiao, Wenjiao; Windley, Brian

    2013-04-01

    The Chinese Altai-East Junggar collage in the southern Altaids hosts three metallogenic belts, which are, from north to south: (1) a volcanogenic massive sulphide (VMS) Cu-Pb-Zn belt; (2) a belt of shear zone-related gold deposits; (3) a porphyry Cu-Au-Mo belt. The VMS deposits formed in two pulses (c. 405 Ma and c. 375 Ma) in the Chinese Altai arc. The porphyry deposits developed in three pulses in the East Junggar arc, the first two synchronous with the VMS mineralization, and the third at c. 330 Ma. The shear zone-related gold deposits developed in the late Carboniferous to Permian at the contact between the Chinese Altai and East Junggar arcs. Time-space distributions of diverse ore deposits across the Altai-East Junggar collage indicate that the collage developed from two independent arcs, the Chinese Altai and the East Junggar. The VMS and porphyry deposits developed in the Chinese Altai and East Junggar arcs, respectively. The Chinese Altai arc is interpreted to be a Japanese-type arc, and the East Junggar arc a Mariana-type arc. During the latest Palaeozoic, the two arcs were juxtaposed by the Erqis Fault, when many shear zone-related lode gold deposits were emplaced. These metallogenic distributions were a likely response to spatially localized mechanisms of crust growth and to the tectonic evolution of the Altai-East Junggar collage, and they are consistent with interpretation of the Altaids as a multiple subduction-accretion collage.

  1. Anisotropy of magnetic susceptibility of Eocene and Miocene sediments in the Qaidam Basin, Northwest China: Implication for Cenozoic tectonic transition and depocenter migration

    NASA Astrophysics Data System (ADS)

    Yu, Xiangjiang; Huang, Baochun; Guan, Shuwei; Fu, Suotang; Cheng, Feng; Cheng, Xiang; Zhang, Tuo; Guo, Zhaojie

    2014-06-01

    Cenozoic evolution of the Qaidam basin, especially its paleostress field, can provide a better understanding of the dynamistic process of the northern Tibetan Plateau. Under certain conditions, Anisotropy of Magnetic Susceptibility (AMS) holds great potential for investigating early tectonic events, even where macroscopic and microscopic evidence of deformation is invisible. A basin-scale AMS study of the middle to late Eocene Xiaganchaigou Formation and the early to middle Miocene Xiayoushashan Formation from seven locations was conducted, covering most outcrops of these two formations within the Qaidam basin. In the western Qaidam basin, principal stress directions inferred from AMS ellipsoids consist with those inferred from fold axial traces, while at Eboliang and in the northern Qaidam basin, most principal stress directions reflected by AMS ellipsoids are different from those reflected by fold axial traces. Two epochs of compressive strain have been identified: an early N-S strain no later than Oligocene and a late NE-SW strain since Miocene. The early N-S compression is more intense in the northern Qaidam basin than that in the western Qaidam basin, while the late NE-SW compression, which dominates the modern NW-SE trending fold axial traces, is more intense in the western Qaidam basin than that in the northern Qaidam basin. The stress transfer provides a reasonable explanation for the southeastward migration of the deposition center in the Qaidam basin during Cenozoic. Moreover, the appearance of E-component compression may be in close relationship with the beginning of the left-lateral strike-slip Kunlun Fault or the eastward channel flow to the south of the Kunlun Fault.

  2. Use of satellite data in runoff forecasting in the heavily forested, cloud-covered Pacific Northwest. [Upper Snake, Boise, Dworshak, Libby and Hungry Horse River Basins

    NASA Technical Reports Server (NTRS)

    Dillard, J. P.; Orwig, C. F. (Principal Investigator)

    1980-01-01

    The author has identified the following significant results. Satellite-derived snow cover data improves forecasts of stream flow but not at a statistically significant amount and should not be used exclusively because of persistent cloud cover. Based upon reconstruction runs, satellite data can be used to augment snow-flight data in the Upper Snake, Boise, Dworshak, and Hungry Horse basins. Satellite data does not compare well with aerial snow-flight data in the Libby basin.

  3. Late Paleozoic tectonic evolution and concentrated mineralization in Balkhash and West Junggar, western part of the Central Asian Orogenic Belt

    NASA Astrophysics Data System (ADS)

    Dong, Shuwen; Chen, Xuanhua; Chen, Zhengle

    2016-04-01

    The Central Asia Orogenic Belt (CAOB) is an important area with significant growth of the crust and metallogeny in the Late Paleozoic. The Balkhash-Junggar tectono-metallogenic belt consists of the Balkhash, the West Junggar, and the East Junggar tectono-metallogenic belts in western part of the Central Asian Orogenic Belt (CAOB). According to the structural geological relationship, the East Junggar, the West Junggar, and the Balkhash belts are considered to be once a continuous E-W-trending tectono-metallogenic belt in Late Carboniferous. The West Junggar belt is featured with NE-trending left-lateral strike-slip faulting tectonic system (WJTS), while the left-lateral strike-slip faults are E-W-trending in the Balkhash belt. The WJTS consists of the Darabut, the Mayile, and the Baerluke faults, and the blocks among them. All these left-lateral strike-slip faults are forming due to the transition of tectonic settings from syn-collisional orogeny to post-collisional extension during the closure of the ocean (the Junggar Sea) in Late Carboniferous, with significant intrusion of batholiths and crust growth occurred in this period. These faults are truncated by the right-lateral strike-slip faults, such as the Chingiz-Junggar fault, and the Central Balkhash fault in Mesozoic. The Balkhash-Junggar tectono-metallogenic belt is important for the occurrence of many well-known super-large and large porphyry Cu-Mo deposits (such as the Kounrad, the Aktogai, the Borly, and the Baogutu deposits), large skarn Cu deposits (in the Sayak ore-filed), large rare metal deposits (such as the East Kounrad, the Zhanet, and the Akshatau deposits), and large gold deposits (such as the Hatu deposit). Zircon U-Pb ages, Re-Os isotopic dating of molybdenites, 40Ar/39Ar thermochronology of hornblendes, muscovites, biotites, and K-feldspars, and zircon and apatite fission track (FT) and (U-Th)/He dating and thermal history modeling, provide a multidisciplinary approach to constrain the whole

  4. Correlation of Plio-Pleistocene deposits of the Lower Rhine Basin (North-West Germany) and the Valle Ricca pits (Central Italy)

    NASA Astrophysics Data System (ADS)

    Arias, Claudio; Bigazzi, Giulio; Bonadonna, Francescopaolo; Brunnacker, Karl; Urban, Brigitte

    Biostratigraphic and palaeomagnetic research has been carried out on selected profiles in North-Western Germany and Central Italy in order to correlate Plio-Pleistocene sections. Around the Réunion subchronozone, vegetation in the Valle Ricca was dominated by a mountain forest type pointing to cool climatic conditions. In the Lower Rhine Basin vegetation had a slightly warmer character, but was also dominated strongly by a mountain type of forest vegetation, characteristic of cooler summers and higher precipitation than at present. Two warmer periods have been determined in the Central Italian profiles; the youngest around the Olduvai reversal, should correspond to the youngest Tiglian beds of the Lower Rhine Basin. Deposits older than the Réunion subzone have not been found in the Valle Ricca. In the Lower Rhine Basin, on the other hand, the Gauss-Matuyama boundary is located between the uppermost Pliocene, the Reuverian C and the Praetiglian.

  5. Godiva Rim Member: A new stratigraphic unit of the Green River Formation in southwest Wyoming and northwest Colorado. Geology of the Eocene Wasatch, Green River, and Bridger (Washakie) Formations, Greater Green River Basin, Wyoming, Utah, and Colorado. Professional paper

    SciTech Connect

    Roehler, H.W.

    1991-01-01

    The report names and describes the Godiva Rim Member of the Green River Formation in the eastern part of the Washakie basin in southwest Wyoming and the central part of the Sand Wash basin in northwest Colorado. The Godiva Rim Member comprises lithofacies of mixed mudflat and lacustrine origin situated between the overlying lacustrine Laney Member of the Green River Formation and the underlying fluvial Cathedral Bluffs Tongue of the Wasatch Formation. The Godiva Rim Member is laterally equivalent to and grades westward into the LaClede Bed of the Laney Member. The Godiva Rim Member of the Green River Formation was deposited along the southeast margins of Lake Gosiute and is correlated to similar lithologic units that were deposited along the northeast margins of Lake Uinta in the Parachute Creek Member of the Green River Formation. The stratigraphic data presented provide significant evidence that the two lakes were periodically connected around the east end of the Uinta Mountains during the middle Eocene.

  6. Evolution of the groundwater system under the impacts of human activities in middle reaches of Heihe River Basin (Northwest China) from 1985 to 2013

    NASA Astrophysics Data System (ADS)

    Mi, Lina; Xiao, Honglang; Zhang, Jianming; Yin, Zhenliang; Shen, Yongping

    2016-06-01

    Investigation of the evolution of the groundwater system and its mechanisms is critical to the sustainable management of water in river basins. Temporal and spatial distributions and characteristics of groundwater have undergone a tremendous change with the intensity of human activities in the middle reaches of the Heihe River Basin (HRB), the second largest arid inland river basin in northwestern China. Based on groundwater observation data, hydrogeological data, meteorological data and irrigation statistical data, combined with geostatistical analyses and groundwater storage estimation, the basin-scaled evolution of the groundwater levels and storage (from 1985 to 2013) were investigated. The results showed that the unbalanced allocation of water sources and expanded cropland by policy-based human activities resulted in the over-abstraction of groundwater, which induced a general decrease in the water table and groundwater storage. The groundwater level has generally fallen from 4.92 to 11.49 m from 1985 to 2013, especially in the upper and middle parts of the alluvial fan (zone I), and reached a maximum depth of 17.41 m. The total groundwater storage decreased by 177.52 × 108 m3; zone I accounted for about 94.7 % of the total decrease. The groundwater balance was disrupted and the groundwater system was in a severe negative balance; it was noted that the groundwater/surface-water interaction was also deeply affected. It is essential to develop a rational plan for integration and management of surface water and groundwater resources in the HRB.

  7. High-quality intensity data from Argentina: archeomagnetic study of pottery fragments from the Guayatayoc-Miraflores basin (Puna de Jujuy, Northwest Argentina)

    NASA Astrophysics Data System (ADS)

    Gomez-Paccard, M.; Chauvin, A.; Albeck, M. E.; Zaburlín, M. A.; Basso, D. M.

    2015-12-01

    Improving geomagnetic field reconstructions clearly poses a high-priority challenge in geomagnetic research today. A better characterization of the geomagnetic field strength in the southern hemisphere is particularly crucial as the limited number of reliable intensity records from this area hamper a meaningful analysis of dipole moment past variations. Here we present the first archeointensity results obtained from several collections of pottery fragments from four agropastoral sites from the Puna of Jujuy (Northwest Argentina), an area never studied before. The ages of the studied sites, dated by radiocarbon analysis, range from the XIII to the XVII centuries. The classical Thellier method with regular partial Thermoremanent magnetization (pTRM) checks and TRM anisotropy and cooling rate corrections has been used for archeointensity determination. From the 82 specimens analysed, 63 gave reliable results. This high success rate indicates that potteries from agropastoral sites of the Puna of Jujuy provide a unique opportunity to further recover past geomagnetic field intensity changes in Northwest Argentina. The new data obtained are the first archeointensity data from this region. The differences observed between the new data, other available archeointensity data from nearby regions, and archeointensity variation curves derived from global models (ARCH3k and SHA.DIF.14), highlights the need for new high-quality data to better constrain the evolution of the Earth magnetic field strength in central South America.

  8. Combined multivariate statistical techniques, Water Pollution Index (WPI) and Daniel Trend Test methods to evaluate temporal and spatial variations and trends of water quality at Shanchong River in the Northwest Basin of Lake Fuxian, China.

    PubMed

    Wang, Quan; Wu, Xianhua; Zhao, Bin; Qin, Jie; Peng, Tingchun

    2015-01-01

    Understanding spatial and temporal variations in river water quality and quantitatively evaluating the trend of changes are important in order to study and efficiently manage water resources. In this study, an analysis of Water Pollution Index (WPI), Daniel Trend Test, Cluster Analysis and Discriminant Analysis are applied as an integrated approach to quantitatively explore the spatial and temporal variations and the latent sources of water pollution in the Shanchong River basin, Northwest Basin of Lake Fuxian, China. We group all field surveys into 2 clusters (dry season and rainy season). Moreover, 14 sampling sites have been grouped into 3 clusters for the rainy season (highly polluted, moderately polluted and less polluted sites) and 2 clusters for the dry season (highly polluted and less polluted sites) based on their similarities and the level of pollution during the two seasons. The results show that the main trend of pollution was aggravated during the transition from the dry to the rainy season. The Water Pollution Index of Total Nitrogen is the highest of all pollution parameters, whereas the Chemical Oxygen Demand (Chromium) is the lowest. Our results also show that the main sources of pollution are farming activities alongside the Shanchong River, soil erosion and fish culture at Shanchong River reservoir area and domestic sewage from scattered rural residential area. Our results suggest that strategies to prevent water pollutionat the Shanchong River basin need to focus on non-point pollution control by employing appropriate fertilizer formulas in farming, and take the measures of soil and water conservation at Shanchong reservoir area, and purifying sewage from scattered villages. PMID:25837673

  9. Combined multivariate statistical techniques, Water Pollution Index (WPI) and Daniel Trend Test methods to evaluate temporal and spatial variations and trends of water quality at Shanchong River in the Northwest Basin of Lake Fuxian, China.

    PubMed

    Wang, Quan; Wu, Xianhua; Zhao, Bin; Qin, Jie; Peng, Tingchun

    2015-01-01

    Understanding spatial and temporal variations in river water quality and quantitatively evaluating the trend of changes are important in order to study and efficiently manage water resources. In this study, an analysis of Water Pollution Index (WPI), Daniel Trend Test, Cluster Analysis and Discriminant Analysis are applied as an integrated approach to quantitatively explore the spatial and temporal variations and the latent sources of water pollution in the Shanchong River basin, Northwest Basin of Lake Fuxian, China. We group all field surveys into 2 clusters (dry season and rainy season). Moreover, 14 sampling sites have been grouped into 3 clusters for the rainy season (highly polluted, moderately polluted and less polluted sites) and 2 clusters for the dry season (highly polluted and less polluted sites) based on their similarities and the level of pollution during the two seasons. The results show that the main trend of pollution was aggravated during the transition from the dry to the rainy season. The Water Pollution Index of Total Nitrogen is the highest of all pollution parameters, whereas the Chemical Oxygen Demand (Chromium) is the lowest. Our results also show that the main sources of pollution are farming activities alongside the Shanchong River, soil erosion and fish culture at Shanchong River reservoir area and domestic sewage from scattered rural residential area. Our results suggest that strategies to prevent water pollutionat the Shanchong River basin need to focus on non-point pollution control by employing appropriate fertilizer formulas in farming, and take the measures of soil and water conservation at Shanchong reservoir area, and purifying sewage from scattered villages.

  10. Spatial-temporal framework for the closure of the Junggar Ocean in central Asia: New SIMS zircon U-Pb ages of the ophiolitic mélange and collisional igneous rocks in the Zhifang area, East Junggar

    NASA Astrophysics Data System (ADS)

    Xu, Xing-Wang; Jiang, Neng; Li, Xian-Hua; Wu, Chu; Qu, Xun; Zhou, Gang; Dong, Lian-Hui

    2015-11-01

    The closure time of the Junggar Ocean is one of the hottest topics surrounding the tectonic evolution of the Central Asian Orogenic Belt (CAOB). This paper reports SIMS zircon U-Pb ages of the ophiolitic mélange and collisional igneous rocks in the Zhifang area, East Junggar. Our new results reveal the following evidence: (1) the West Hill ophiolitic mélange in the Zhifang area contains segments of the 371 Ma MORB-type layered rocks and 363 Ma oceanic islands, which were intruded by the 348 Ma syn-collisional quartz diorites; (2) the ophiolitic mélange and 348 Ma syn-collisional quartz diorites are overlain by the 342 Ma andesitic tuffs; and (3) the 342 Ma andesitic tuffs and successive 332 Ma granodiorites-gabbro were formed at late-collisional setting, whereas the 314 Ma granitic porphyry at post-collisional setting. We suggest that the Junggar Ocean in the Zhifang area was opened before 371 Ma and 363 Ma, and possibly closed before 348 Ma. By combining the published U-Pb ages of the Mayile-Tangbale-Darbute-Kalamaili-Zhifang-Daheishan (MTDKZD) ophiolite belt, Early-Carboniferous volcanic rocks unconformably overlying the MTDKZD ophiolite belt, bimodal volcanic rocks and granitoids within and adjacent to the MTDKZD ophiolite belt, it is suggested that the Junggar Ocean was possibly opened scissors-like from the Neoproterozoic-Ordovician Mayile-Tangbale ocean eastwards through the Silurian-Devonian Darbute-Karamay ocean finally to the Devonian-Early-Carboniferous Kalamaili-Zhifang ocean, and closed scissors-like from the Zhifang-Kalamaili area in the eastern segment westwards to the Darbute-Karamay area in the western segment. Tectonic collage between the Yemaquan-Xiemisitai arc and Junggar block occurred at approximately 343-348 Ma. The Junggar orogenic belt went through late-collisional stage at 343-330 Ma, post-collisional period after 330 Ma, and post-collisional extensional regime after 320 Ma with an intensive stage at around 303 Ma.

  11. Asthenosphere-lithosphere interaction triggered by a slab window during ridge subduction: Trace element and Sr-Nd-Hf-Os isotopic evidence from Late Carboniferous tholeiites in the western Junggar area (NW China)

    NASA Astrophysics Data System (ADS)

    Tang, Gong-Jian; Wyman, Derek A.; Wang, Qiang; Li, Jie; Li, Zheng-Xiang; Zhao, Zhen-Hua; Sun, Wei-Dong

    2012-05-01

    Tholeiites occur in a variety of geological settings, e.g., mid-ocean ridge, back-arc basin, ocean island, island arc and intra-continent, and their geochemical and isotopic characteristics vary according to the corresponding geodynamic environments. Here we investigated the Hatu tholeiitic basalts and basaltic andesites of the western Junggar region, Central Asian Orogenic Belt (CAOB). LA-ICPMS zircon U-Pb analyses indicate that the Hatu tholeiites were generated in the Late Carboniferous (~ 315 Ma). All the studied rock samples are characterized by flat rare earth elements pattern on chondrite-normalized plot, and negligible Nb, Ta and Ti anomalies on mid-ocean-ridge basalt normalized plots. They are also characterized by moderate positive ɛNd(t) (+ 5.25 to + 5.94), ɛHf(t) (+ 13.24 to + 14.89), highly radiogenic Os isotope compositions (187Os/188Os315Ma = 0.1338-0.3547), and relatively low (87Sr/86Sr)i ratios (0.7044 to 0.7048). Taking into account their geological characteristics, the occurrence of nearby ophiolites and the types of contemporaneous magmatic rocks found in the western Junggar region, we propose that the Hatu basalts were generated by slab window-related processes following a spreading ridge subduction beneath the Keramay intra-oceanic island arc. During this process, deep and enriched asthenospheric mantle rose to the edge of the subducted oceanic lithosphere, its melts infiltrating the subducted oceanic lithosphere and reacting with peridotites. Therefore, the Hatu tholeiites are interpreted as a result of melting of a mixed mantle source consisting of subducted depleted oceanic lithosphere and a deep, enriched upwelling asthenospheric mantle. Incongruent dynamic melting modeling of trace element compositions indicates that the Hatu basalts could have been derived from large degrees of melting (~ 10%) of such a mixed mantle source. This newly recognized mechanism is a natural consequence of the diversity of contemporaneous potential mantle

  12. Sedimentary basins and crustal thickening

    NASA Astrophysics Data System (ADS)

    Cobbold, P. R.; Davy, P.; Gapais, D.; Rossello, E. A.; Sadybakasov, E.; Thomas, J. C.; Tondji Biyo, J. J.; de Urreiztieta, M.

    1993-07-01

    We consider the development of sedimentary basins in a tectonic context dominated by horizontal shortening and vertical thickening of the crust. Well-known examples are foreland basins; others are ramp basins and buckle basins. We have reproduced various styles of compressional basins in experiments, properly scaled for gravity. A multilayered model lithosphere, with brittle and ductile layers, floats on a model asthenosphere. A computer-driven piston provides shortening and thickening, synchronous with erosion and sedimentation. After a first stage of lithospheric buckling, thrust faults appear, mainly at inflection points. Slip on an isolated reverse fault is accompanied by flexure. Footwall flexure results in a foreland basin and becomes accentuated by sedimentation. Hangingwall flexure is less marked, but may become accentuated by erosion. Motion on a fault leads to hangingwall collapse at the surface. Either footwall sedimentation or hangingwall erosion tends to prolong the active life of a reverse fault. Slip on any pair of closely spaced reverse faults of opposite vergence results in a ramp basin. Simultaneous slip produces a symmetric ramp basin, whereas alternating slip results in a butterfly-shaped basin, with superposed foredeeps. Some well-developed ramp basins become pushed down, until bounding faults meet at the surface and the basin disappears from view. At this stage, the basin depth is equivalent to 15 km or more. Slip on any pair of widely spaced reverse faults of opposite vergence results in a pronounced central anticline, between two distinct foredeeps. In Central Asia and in Western Europe, Cenozoic crustal thickening is due to continental collision. For Central Asia (Western China, Kyrgyzstan, Uzbekistan, Tajikistan), we have compiled a regional structure-contour map on the base of the Tertiary, as well as 4 regional sections. Foreland basins and ramp basins are numerous and associated with Cenozoic thrusts. Large basins (Tarim, Junggar

  13. Population structure and effective/census population size ratio in threatened three-spined stickleback populations from an isolated river basin in northwest Spain.

    PubMed

    Pérez-Figueroa, A; Fernández, C; Amaro, R; Hermida, M; San Miguel, E

    2015-08-01

    Variability at 20 microsatellite loci was examined to assess the population genetic structure, gene flow, and effective population size (N(e)) in three populations of three-spined stickleback (Gasterosteus aculeatus) from the upper basin of the Miño River in Galicia, NW Spain, where this species is threatened. The three populations showed similar levels of genetic diversity. There is a significant genetic differentiation between the three populations, but also significant gene flow. N(e) estimates based on linkage disequilibrium yielded values of 355 for the Miño River population and 241 and 311 for the Rato and Guisande Rivers, respectively, although we expect that these are overestimates. N(e) estimates based on temporal methods, considering gene flow or not, for the tributaries yielded values of 30-56 and 47-56 for the Rato and Guisande Rivers, respectively. Estimated census size (N(c)) for the Rato River was 880 individuals. This yielded a N(e)/N(c) estimate of 3-6 % for temporal estimation of N(e), which is within the empirical range observed in freshwater fishes. We suggest that the three populations analyzed have a sufficient level of genetic diversity with some genetic structure. Additionally, the absence of physical barriers suggests that conservation efforts and monitoring should focus in the whole basin as a unit.

  14. RESTORING WILD SALMON TO THE PACIFIC NORTHWEST: CHASING AN ILLUSION

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon "stocks" (a group of interbreeding individuals that is roughly equivalent to a "population") have declined and some have been ...

  15. FUTURE OF PACIFIC NORTHWEST SALMON: SCIENCE AND POLICY IN ACTION

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon stocks (a group of interbreeding individuals that is roughly equivalent to a "population") have declined and some have disappear...

  16. PACIFIC NORTHWEST SALMON: FORECASTING THEIR STATUS IN 2100

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon stocks (a group of interbreeding individuals that is roughly equivalent to a "population") have declined and some have disappear...

  17. RESTORING WILD SALMON TO THE PACIFIC NORTHWEST: CHASING AN ILLUSION?

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon "stocks" (a group of interbreeding individuals that is roughly equivalent to a "population) have declined and some have been e...

  18. Petrography and diagenesis of reservoir and non-reservoir sandstones in Shattuck Member of Queen Formation, northwest shelf of Permian basin

    SciTech Connect

    Malicse, A.; Siegel, J.; Mazzullo, J.

    1988-02-01

    The Shattuck Member is a thick (6-20 m) sandstone that defines the top of the Queen Formation (Permian, Guadalupian) and is a major hydrocarbon reservoir on the Northwestern shelf of the Permian basin. The Shattuck was deposited in desert dune and interdune, dry and wet sand sheet, and sandy sabkha environments during a lowstand of sea level. The desert dune, interdune, and dry sand sheet deposits constitute the producing horizons in the Shattuck, whereas the wet sand sheet and sabkha deposits are generally non-productive. The purposes of this study are to examine the petrographic characteristics of the producing and non-producing horizons with petrographic and scanning electron microscopes, and to determine their provenance and diagenetic history.

  19. Approximation of continuity of lenticular Mesaverde sandstone lenses, utilizing close-well correlations, Piceance Basin, northwest, Colorado. Western Gas Sands Project

    SciTech Connect

    Not Available

    1982-11-01

    Mesaverde Group sandstone units in 13 closely-spaced wells in the central and southern Piceance Basin of Colorado were correlated utilizing wireline log response quantitatively and qualitatively. Based on these correlations, the environmental subdivisions of the Mesaverde Group were characterized as follows. Paralic (upper mixed-marine) zone, occurring in the uppermost Mesaverde, includes thick sandstone units which are interpreted to be regionally continuous. Fluvial zone, containing point-bars 20 to 30+ ft thick, is interpreted to be correlatable to a maximum of 6800 ft. Paludal zone, which has insufficient data to adequately characterize the sand units. However, 63 percent of the units are correlatable across at least 139 ft. An approximation of the dimensional characteristics of Mesaverde sandstone units has potential applications in designing hydraulic fracturing treatments and estimating gas reserves more accurately. 16 figures, 2 tables

  20. Participatory Modeling Processes to Build Community Knowledge Using Shared Model and Data Resources and in a Transboundary Pacific Northwest Watershed (Nooksack River Basin, Washington, USA)

    NASA Astrophysics Data System (ADS)

    Bandaragoda, C.; Dumas, M.

    2014-12-01

    As with many western US watersheds, the Nooksack River Basin faces strong pressures associated with climate variability and change, rapid population growth, and deep-rooted water law. This transboundary basin includes contributing areas in British Columbia, Canada, and has a long history of joint data collection, model development, and facilitated communication between governmental (federal, tribal, state, local), environmental, timber, agricultural, and recreational user groups. However, each entity in the watershed responds to unique data coordination, information sharing, and adaptive management regimes and thresholds, further increasing the complexity of watershed management. Over the past four years, participatory methods were used to compile and review scientific data and models, including fish habitat (endangered salmonid species), channel hydraulics, climate data, agricultural, municipal and industrial water use, and integrated watershed scale distributed hydrologic models from over 15 years of projects (from jointly funded to independent shared work by individual companies, agencies, and universities). A specific outcome of the work includes participatory design of a collective problem statement used for guidance on future investment of shared resources and development of a data-generation process where modeling results are communicated in a three-tiers for 1) public/decision-making, 2) technical, and 3) research audiences. We establish features for successful participation using tools that are iteratively developed, tested for usability through incremental knowledge building, and designed to provide rigor in modeling. A general outcome of the work is ongoing support by tribal, state, and local governments, as well as the agricultural community, to continue the generation of shared watershed data using models in a dynamic legal and regulatory setting, where two federally recognized tribes have requested federal court resolution of federal treaty rights

  1. Spatial-temporal variability of soil water content in a cropland-shelterbelt-desert site in an arid inland river basin of Northwest China

    NASA Astrophysics Data System (ADS)

    Shen, Qin; Gao, Guangyao; Hu, Wei; Fu, Bojie

    2016-09-01

    Knowledge of the spatial-temporal variability of soil water content (SWC) is critical for understanding a range of hydrological processes. In this study, the spatial variance and temporal stability of SWC were investigated in a cropland-shelterbelt-desert site at the oasis-desert ecotone in the middle of the Heihe River Basin, China. The SWC was measured on 65 occasions to a depth of 2.8 m at 45 locations during two growing seasons from 2012 to 2013. The standard deviation of the SWC versus the mean SWC exhibited a convex upward relationship in the shelterbelt with the greatest spatial variation at the SWC of around 22.0%, whereas a linearly increasing relationship was observed for the cropland, desert, and land use pattern. The standard deviation of the relative difference was positively linearly correlated with the SWC (p < 0.05) for the land use pattern, whereas such a relationship was not found in the three land use types. The spatial pattern of the SWC was more time stable for the land use pattern, followed by desert, shelterbelt, and cropland. The spatial pattern of SWC changed dramatically among different soil layers. The locations representing the mean SWC varied with the depth, and no location could represent the whole soil profile due to different soil texture, root distribution and irrigation management. The representative locations of each soil layer could be used to estimate the mean SWC well. The statistics of temporal stability of the SWC could be presented equally well with a low frequency of observation (30-day interval) as with a high frequency (5-day interval). Sampling frequency had little effect on the selection of the representative locations of the field mean SWC. This study provides useful information for designing the optimal strategy for sampling SWC at the oasis-desert ecotone in the arid inland river basin.

  2. Soil Water Content Variations and Hydrological Relations of a Typical Land Use Pattern in an Arid Inland River Basin of Northwest China

    NASA Astrophysics Data System (ADS)

    Shen, Q.; Gao, G.; Fu, B.

    2014-12-01

    A good understanding of the interrelations of a typical land use pattern was essential for ecosystem management and water resources distribution in arid inland river basin. This study was conducted to compare the soil water content and explore the hydrological relation of a cropland-treebelt-desert system at the oasis-desert ecotone in the middle of China's Heihe River Basin. Volumetric soil water content, the relationship between treebelt water use characteristics and groundwater, and plant root distribution were measured. The results showed that the mean volumetric soil water content in the 0-200 cm layer was greater in the cropland (8.88%) than that in the treebelt (5.78%) and desert (4.37%) as a result of frequent irrigation events. However, the cropland had noticeably lower mean volumetric soil water content below 200 cm depth (14.27%), compared to treebelt (18.07%) and desert (17.30%) with deeper roots to suck up groundwater. Groundwater table had negative impact on tree transpiration. The contribution of groundwater to tree transpiration was estimated to be 35.1% and 19.0% in 2012 and 2013, respectively. The great precipitation in 2013 weakened the dependence of tree transpiration on groundwater. The hydrological relation between treebelt and cropland in the upper soil layer was mainly occurred by treebelt root water uptake from cropland. The biomass of fine treebelt root extended into the cropland decreased logarithmically with the distance from the cropland-treebelt interface, which resulted in the smaller volumetric soil water content in the cropland with more proximity to the treebelt. Meanwhile, the threshold distance of cropland irrigation influencing the tree transpiration was about 8 m. The hydrological relation in the lower soil layer among cropland-treebelt-desert was caused by groundwater recharge, as cropland irrigation raised up the groundwater level to replenish the deep soil layer. The percolation in the cropland was an important water source

  3. Mid-Wisconsin to Holocene permafrost and landscape dynamics based on a drained lake basin core from the northern Seward Peninsula, northwest Alaska

    USGS Publications Warehouse

    Lenz, Josefine; Grosse, Guido; Jones, Benjamin M.; Anthony, Katey M. Walter; Bobrov, Anatoly; Wulf, Sabine; Wetterich, Sebastian

    2016-01-01

    Permafrost-related processes drive regional landscape dynamics in the Arctic terrestrial system. A better understanding of past periods indicative of permafrost degradation and aggradation is important for predicting the future response of Arctic landscapes to climate change. Here, we used a multi-proxy approach to analyse a ~ 4 m long sediment core from a drained thermokarst lake basin on the northern Seward Peninsula in western Arctic Alaska (USA). Sedimentological, biogeochemical, geochronological, micropalaeontological (ostracoda, testate amoebae) and tephra analyses were used to determine the long-term environmental Early-Wisconsin to Holocene history preserved in our core for central Beringia. Yedoma accumulation dominated throughout the Early to Late-Wisconsin but was interrupted by wetland formation from 44.5 to 41.5 ka BP. The latter was terminated by the deposition of 1 m of volcanic tephra, most likely originating from the South Killeak Maar eruption at about 42 ka BP. Yedoma deposition continued until 22.5 ka BP and was followed by a depositional hiatus in the sediment core between 22.5 and 0.23 ka BP. We interpret this hiatus as due to intense thermokarst activity in the areas surrounding the site, which served as a sediment source during the Late-Wisconsin to Holocene climate transition. The lake forming the modern basin on the upland initiated around 0.23 ka BP and drained catastrophically in spring 2005. The present study emphasises that Arctic lake systems and periglacial landscapes are highly dynamic and that permafrost formation as well as degradation in central Beringia was controlled by regional to global climate patterns as well as by local disturbances.

  4. Late Paleozoic to Jurassic tectonic evolution of the Bogda area (northwest China): Evidence from detrital zircon U-Pb geochronology

    NASA Astrophysics Data System (ADS)

    Tang, Wenhao; Zhang, Zhicheng; Li, Jianfeng; Li, Ke; Chen, Yan; Guo, Zhaojie

    2014-06-01

    Since the Cenozoic, the Tian Shan is rejuvenated by crustal shortening related to the ongoing India-Asia collision. However, the tectonic process prior to the Cenozoic remains ambiguous, especially in the Bogda area of the eastern Tian Shan. The continuous Late Paleozoic-Mesozoic sequences in the Bogda area record abundant information about the basin-mountain interaction. U-Pb (LA-ICP-MS) dating of detrital zircons from seven sandstone samples from Permian to Jurassic was used to investigate the changes of provenance and basin-mountain interaction in the Bogda area. During the Permian, proximal and synchronous pyroclastic materials were the major source. The Late Paleozoic magmatic belt in the North Tian Shan (NTS) had gradually become one of the main sources by the Late Permian, which implies the uplift and exhumation in the NTS area. This is interpreted in terms of near-source sedimentation in basin developing in a post-orogenic extension setting. The large range of U-Pb ages of detrital zircons observed in the Early-Middle Jurassic sediments encompasses most of the available sources implying a wide drainage pattern developing on a rather flat topography. Re-emergence of the Early Permian peak in the spectrum implies that the Bogda Mountains has existed as a gentle positive relief and began to provide materials to the submountain regions. The southern Junggar Basin extended towards to the south and evolved as a passively subsiding basin from the Middle Triassic to the Middle Jurassic. However, the synchronous pyroclastic (tuff) and the exhumed late Paleozoic detrital materials from the uplifted Bogda Mountains were the major component of the Upper Jurassic sediments. Associated to the conglomerate in the Kalaza Formation, the basin-range evolution entered a compression uplift stage. The basin pattern evolution of the Bogda area is consistent with that of the southern Junggar Basin.

  5. Sensitive response of desert vegetation to moisture change based on a near-annual resolution pollen record from Gahai Lake in the Qaidam Basin, northwest China

    NASA Astrophysics Data System (ADS)

    Zhao, Yan; Yu, Zicheng; Chen, Fahu; Liu, Xiuju; Ito, Emi

    2008-05-01

    We present a 50-year pollen record at near-annual resolution from Gahai Lake in the Qaidam Basin on the northeastern Tibetan Plateau. Chronology of a 22-cm short core was established by 210Pb and 137Cs analysis. The pollen results at 0.5 cm intervals show large changes in Artemisia/Chenopodiaceae (A/C) ratios from < 0.2 to 0.95 in the last 50 years. High (low) A/C ratios represent increase (decrease) in steppe pollen production, which correspond to high (low) relative humidity observed at nearby Delingha weather station. On the basis of good correspondence with instrumental records and carbonate content from Gahai Lake, we conclude that A/C ratio is sensitive to moisture change and can be a very useful index in reconstructing paleoclimate of arid regions. Comparison with pollen and snow accumulation data from Dunde ice core suggests that effective moisture at low and high elevations shows the opposite relationship when mountain precipitation was extremely high, possibly due to topography-induced uplifting and subsiding air dynamics.

  6. Case Studies of Massive Gravity Slides Imaged in 3D Seismic Volumes: Passive Margin and Basinal Settings (West Africa and Northwest Europe)

    NASA Astrophysics Data System (ADS)

    Benjamin, U. K.; Le, A. N.; Oluboyo, A. P.; Irving, D. H.; Huuse, M.

    2010-12-01

    Regionally extensive scour surfaces on continental margins and in epeiric basins develop due to two major processes: submarine landslides, mainly affecting slopes in excess of 1 degree and subglacial scour beneath ice streams draining alpine or continental ice sheets. Both types of surfaces can extend for tens to hundreds of kilometres in the dip and strike directions, with tens of metres relief across tens of kilometres long scours and ridges. Correct interpretation within a sediment system tract enlightens models of synchronous glacial, marine and climatic conditions. We present four megaslides imaged in, and interpreted from 3D seismic volumes acquired in diverse settings: 1: On the passive margin shelf of Cameroon, large-scale, downslope-oriented striations extend 40 km from the upper slope to the deep basin area. Individual striations are 20-50 m wide, 8 km long, 5-10 ms TWT deep, and broadly arcuate. The striations present in two sets and mark the base of a chaotic-to-discontinuous, high-amplitude package with chaotic, low amplitude reflections in the unstriated area. The facies is interpreted as a zone of repeated gravity sliding during the early Pleistocene in response to tectono-climatic forcing. 2: A basal surface from the Moray Firth, UK Central North Sea, tentatively dated as Paleocene in age. It is 20 km in width, over 40 km long and displays parallel grooves measuring typically 100-1000 m wide, 10-20 km long, of sinuous form along the section imaged in the dataset and with evidence of post-slump failure along the margins of the slide zone. It is interpreted as scour caused by a single sliding event. 3: An areally extensive scoured surface measuring 45x45 km that is part of a larger Pliocene system on the Angolan margin. The basal shear surface is marked by divergent scours. The geometry and spatial location of this flow are confined by listric faults and salt-cored folds with compressional thrusts within the distal toe of deposits on the flanks of

  7. Agricultural crop mapping and classification by Landsat images to evaluate water use in the Lake Urmia basin, North-west Iran

    NASA Astrophysics Data System (ADS)

    Fazel, Nasim; Norouzi, Hamid; Madani, Kaveh; Kløve, Bjørn

    2016-04-01

    Lake Urmia, once one of the largest hypersaline lakes in the world has lost more than 90% of its surface body mainly due to the intensive expansion of agriculture, using more than 90% of all water in the region. Access to accurate and up-to-date information on the extent and distribution of individual crop types, associated with land use changes and practices, has significant value in intensively agricultural regions. Explicit information of croplands can be useful for sustainable water resources, land and agriculture planning and management. Remote sensing, has been proven to be a more cost-effective alternative to the traditional statistically-based ground surveys for crop coverage areas that are costly and provide insufficient information. Satellite images along with ground surveys can provide the necessary information of spatial coverage and spectral responses of croplands for sustainable agricultural management. This study strives to differentiate different crop types and agricultural practices to achieve a higher detailed crop map of the Lake Urmia basin. The mapping approach consists of a two-stage supervised classification of multi-temporal multi-spectral high resolution images obtained from Landsat imagery archive. Irrigated and non-irrigated croplands and orchards were separated from other major land covers (urban, ranges, bare-lands, and water) in the region by means of maximum Likelihood supervised classification method. The field data collected during 2015 and land use maps generated in 2007 and Google Earth comparisons were used to form a training data set to perform the supervised classification. In the second stage, non-agricultural lands were masked and the supervised classification was applied on the Landsat images stack to identify seven major croplands in the region (wheat and barley, beetroot, corn, sunflower, alfalfa, vineyards, and apple orchards). The obtained results can be of significant value to the Urmia Lake restoration efforts which

  8. [Soil carbon and nitrogen sequestration following cropland to forage grassland conversion in the marginal land in the middle of Heihe River basin, northwest China].

    PubMed

    Su, Yong-zhong

    2006-07-01

    Changes in soil organic carbon (SOC) and total nitrogen (TN) stocks were studied following croplands were converted to forage grasslands (alfalfa) for five years on the marginal land at the edge of oasis in the middle reaches of Heihe river basin. Soil from 12 paired forage land/adjacent cropland on the two soil types (Typic Torripsamments and Typic Calciorthids) was sampled at the three depths of 0-5, 5-10 and 10-20 cm and analyzed for SOC and TN, particulate organic carbon (POC) and nitrogen (PON). The studied soils had very low SOC and N concentrations. SOC stock at the 0-20 cm depth increased by 22.1%-27.8% after conversion of annually crop to perennial alfalfa for four years, and carbon sequestration rate was estimated to be on average 0.47 Mg/(hm2 x a). The greatest change in SOC stock occurred at the 0-5 cm surface layer with an increase of 32%-66%. No significant TN stock was found at the 0-20 cm depth, however, it increased at the 0-5 cm surface layer by 12.8% and 48.1% for Typic Torripsamments and Typic Calciorthids, respectively. Changes in POC and PON stocks were more significant than those in SOC and total N following conversion of crop to forage, and the percentage of distributions of POC and PON increased. POC and PON stocks at the 0-20 cm depth increased by 22.8%-42.7% and 18.6%-57.6% with the greatest increases at the 0-5 cm layer. The increase in soil C pool was mainly attributed to the increase of POC formation after the marginal lands converted to perennial forage cover. Typic Calciorthids with lower SOC concentration had relatively lower C sequestration rate but more significant effects of C and N sequestration compared with Typic Torripsamments.

  9. [Variations of Picea crassifolia tree-ring cell structure and their implications to past climate in eastern margin of Qaidam Basin, Northwest China].

    PubMed

    Li, Yan; Liang, Er-Yuan; Shao, Xue-mei

    2008-03-01

    Tree-ring samples of Picea crassifolia were collected from the upper tree-line in the eastern mountainous area of Qaidam Basin in Qinghai Province. The tree-ring width and the cell number and size of the tree-ring were measured, and the standard chronologies for the early-wood cell number, late-wood cell number, total cell number of tree-rings, maximum cell size, and minimum cell size were constructed. By using correlation analysis and the response functions between cell characteristic indices and 1970-2000 climate factors at Chaka meteorological station which was close to the sampling site, the relationships between P. crassifolia growth at cell scale and climate factors were discussed. The results showed that the early-wood cell number was positively correlated to the wintertime temperature from previous October to current March, while the late-wood cell number was positively correlated to the minimum temperature in previous November and December and to the mean temperature in current July and August. Both the early-wood and the late-wood cell numbers were negatively correlated to the precipitation in July, and the early-wood cell number was positively correlated to the precipitation in May. The chronology of maximum cell size of early-wood was positively related to the precipitation in February, while that of minimum cell size of late-wood was positivelyrelated to the precipitation in August. It was concluded that the cell number and cell size could not only reveal the information of temperature change, which was recorded by tree ring width as well, but also provide additional information of precipitation. Since different types of tree-ring indices contained different climate information, multiple aspects of climate change information could be extracted from different tree-ring indices of the same species at the same site, and the cell level tree ring characteristics had great potential to supply the information regarding past climate. PMID:18533520

  10. Parana basin

    SciTech Connect

    Zalan, P.V.; Wolff, S.; Conceicao, J.C.J.; Vieira, I.S.; Astolfi, M.A.; Appi, V.T.; Zanotto, O.; Neto, E.V.S.; Cerqueira, J.R.

    1987-05-01

    The Parana basin is a large intracratonic basin in South America, developed entirely on continental crust and filled with sedimentary and volcanic rocks ranging in age from Silurian to Cretaceous. It occupies the southern portion of Brazil (1,100,000 km/sup 2/ or 425,000 mi/sup 2/) and the eastern half of Paraguay (100,000 km/sup 2/ or 39,000 mi/sup 2/); its extension into Argentina and Uruguay is known as the Chaco-Parana basin. Five major depositional sequences (Silurian, Devonian, Permo-Carboniferous, Triassic, Juro-Cretaceous) constitute the stratigraphic framework of the basin. The first four are predominantly siliciclastic in nature, and the fifth contains the most voluminous basaltic lava flows of the planet. Maximum thicknesses are in the order of 6000 m (19,646 ft). The sequences are separated by basin wide unconformities related in the Paleozoic to Andean orogenic events and in the Mesozoic to the continental breakup and sea floor spreading between South America and Africa. The structural framework of the Parana basin consists of a remarkable pattern of criss-crossing linear features (faults, fault zones, arches) clustered into three major groups (N45/sup 0/-65/sup 0/W, N50/sup 0/-70/sup 0/E, E-W). The northwest- and northeast-trending faults are long-lived tectonic elements inherited from the Precambrian basement whose recurrent activity throughout the Phanerozoic strongly influenced sedimentation, facies distribution, and development of structures in the basin. Thermomechanical analyses indicate three main phases of subsidence (Silurian-Devonian, late Carboniferous-Permian, Late Jurassic-Early Cretaceous) and low geothermal gradients until the beginning of the Late Jurassic Permian oil-prone source rocks attained maturation due to extra heat originated from Juro-Cretaceous igneous intrusions. The third phase of subsidence also coincided with strong tectonic reactivation and creation of a third structural trend (east-west).

  11. 17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING ...

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

    17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING OVER SETTLING BASIN, SPARE BENT MATERIAL IN RIGHT-HAND FOREGROUND, BYPASS FLUME, AND SHACK #6 IN BACKGROUND, LOOKING NORTHWEST - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  12. PACIFIC NORTHWEST CYBER SUMMIT

    SciTech Connect

    Lesperance, Ann M.; Matlock, Gordon W.; Becker-Dippmann, Angela S.; Smith, Karen S.

    2013-08-07

    On March 26, 2013, the Snohomish County Public Utility District (PUD) and the U.S. Department of Energy’s (DOE’s) Pacific Northwest National Laboratory (PNNL) jointly hosted the Pacific Northwest Cyber Summit with the DOE’s Office of Electricity Delivery and Energy Reliability, the White House, Washington State congressional delegation, Washington State National Guard, and regional energy companies.

  13. Kaiser Permanente Northwest

    Cancer.gov

    Kaiser Permanente Northwest's Center for Health Research was created to study health maintenance organizations by scientists were recruited from a variety of fields to study a range of health and medical care issues.

  14. Northwest Washington State

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Portions of northwest Washington State (48.0N, 122.5) can be seen in this view as well as portions of British Columbia, Canada. The snow covered Cascade Mountains are on the eastern side of the scene. Vancouver Island is visible in the northeast corner of the photo. The strait of Juan de Fuca separates Vancouver Islannd from the northwest corner of Washington. Seattle is near the center and the snow covered Olympic Mountains are to the east.

  15. Comment on: Alam Akhtar, Ahmad Shabir, Sultan Bhat, M., Ahmad Bashir, 2015. Tectonic evolution of Kashmir basin in northwest Himalayas. Geomorphology doi: 10.1016/j.geomorph.2015.03.025

    NASA Astrophysics Data System (ADS)

    Shah, A. A.

    2016-01-01

    Alam et al. (2015) have challenged the classic piggyback tectonic model for the development of Kashmir basin, NW Himalaya. However, all the evidence shown is completely contrary to the geologic, tectonic, structural, seismologic, geodetic, and geomorphic data of previous works. A perfectly planar major (~ 165 km) dextral strike-slip fault has been mapped; however, with such planar geometry, any strike-slip fault cannot produce a pull-apart basin because such basins are characteristic features of step-overs and linkage fault geometries. And the Horsetail structures are impossible for a major planar strike-slip fault geometry that is proposed by the authors. The recent geodetic data of the Kashmir basin strongly refutes the pure strike-slip model. Therefore, the structures, geomorphology, geology, and kinematics associated with typical dextral strike-slip fault geometry completely contradict to what has been proposed by Alam et al. (2015).

  16. VIEW TO SOUTHEAST FROM NORTHWEST CORNER OF BASING NO. 4 ...

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

    VIEW TO SOUTHEAST FROM NORTHWEST CORNER OF BASING NO. 4 (SECOND BASING FROM THE EAST) SHOWING CRANEWAY AND GALLERY BETWEEN BASINS NO. 4 AND 5. GENERAL WAREHOUSE IS IN BACKGROUND - Rosie the Riveter National Historical Park, Graving Docks, Shipyard No. 3, Richmond, Contra Costa County, CA

  17. Geochronology and isotope geochemistry of the Baogutu porphyry copper deposit in the West Junggar region, Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Shen, Ping; Shen, Yuanchao; Pan, Hongdi; Li, Xian-hua; Dong, Lianhui; Wang, Jingbin; Zhu, Heping; Dai, Huawu; Guan, Weina

    2012-04-01

    The Baogutu copper deposit, a newly-discovered middle-sized porphyry copper deposit, is located in the West Junggar region of Xinjiang, NW China. Baogutu is associated with a Late Carboniferous intrusive complex that was emplaced into Lower Carboniferous volcano-sedimentary strata. The intrusive complex comprises main-stage diorites and minor late-stage diorite porphyries. Their intrusive activity occurred in 313.0 ± 2.2 Ma to 312.3 ± 2.2 Ma based on U-Pb zircon SIMS analyses. Molybdenite separated from ore-bearing quartz veins yields Re-Os model ages from 309.4 ± 4.4 Ma to 314.1 ± 4.5 Ma with a weighted mean age of 312.4 ± 1.8 Ma. Biotites, separated from fresh diorite and hydrothermal breccias in main-stage diorites, yield 40Ar/39Ar plateau ages of 308.26 ± 1.88 and 305.69 ± 1.76 Ma, respectively. These dates obtained from three independent dating techniques constrain the ore-forming age of the Baogutu deposit. Stable isotopes (H, O, S) and radiogenic isotope (Pb) have been used to discriminate the sources of the ore-forming fluid at Baogutu. The δ18O (1.14-1.74‰) and δD (-74‰ to -98‰) data indicate that the water of the ore-forming fluids was derived from magmatic water. The δ34S values (-0.24‰ to +0.4‰) show that the sulfur isotope composition of the ore fluids is characterized by magma sulfur. Lead isotope compositions (206Pb/204Pb = 17.92-18.89, 207Pb/204Pb = 15.45-15.62, 208Pb/204Pb = 37.68-38.36) indicate that the lead of the ore fluids is derived from the mantle. These data confirm the occurrence of a Cu-Au-Mo mineralizing event at Late Carboniferous in the Baogutu region and the ore-forming fluids are mainly derived from the mantle. The event is inferred to be associated with Late Carboniferous Junggar oceanic crust subduction.

  18. 7. LOOKING NORTHWEST TOWARD NORTHWEST END OF BRIDGE FROM UNDERNEATH, ...

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

    7. LOOKING NORTHWEST TOWARD NORTHWEST END OF BRIDGE FROM UNDERNEATH, SHOWING CONCRETE SUPPORTS FOR CANTILEVERED WALKWAY (ON RIGHT) - Lincoln Avenue Viaduct, Spanning Union Pacific Railroad between Baring Cross Bridge & Union Station, Little Rock, Pulaski County, AR

  19. 3. NORTHWEST INTERIOR VIEW OF NORTHWEST ROOM WITH EQUIPMENT FROM ...

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

    3. NORTHWEST INTERIOR VIEW OF NORTHWEST ROOM WITH EQUIPMENT FROM CENTER INTERIOR - Juniata Mill Complex, Assay Office, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  20. Suicide in Northwest Alaska.

    ERIC Educational Resources Information Center

    Travis, Robert

    1983-01-01

    Between 1975 and 1979 the Alaskan Native suicide rate (90.9 per 100,000) in Northwest Alaska was more than seven times the national average. Alienation, loss of family, low income, alcohol abuse, high unemployment, and more education were factors related to suicidal behavior. Average age for suicidal behavior was 22.5. (Author/MH)

  1. Is the Neogene series of the Northern Foreland Basin of the Tian Shan Range indicative of tectonic or climatic change?

    NASA Astrophysics Data System (ADS)

    Armitage, J. J.; Barrier, L.

    2013-12-01

    In the Junggar Basin - the northern foreland basin of the Tian Shan Range in Central Asia - there are striking transitions in depositional style during the Cenozoic, from fine grain to coarse gravel deposits. There is continued debate as to if this coarsening is due to a change in surface run-off and frequent shifts in climatic conditions, or increased tectonic uplift. To explore the causes of these sedimentological changes, we compare the results of a model of erosion and deposition linked to flexure of the lithosphere, against the exposed sections of the transitions in deposition across the southern margin of the basin. An increase in tectonic uplift causes an temporary reduction in grain size followed by progradation of coarser material into the basin. The initial retrogradation is caused by the ratio of accommodation space to sediment supply being transiently high, as catchment erosion responds to the change in slope. In contrast, when the system is subject to an increase in surface run-off, there is a rapid increase in sediment delivery to the basin but little change in the down-system fining of gravel deposits. There is no retrogradation in this scenario due to erosion of the upper few km of previous deposits. The general lack of basin wide change in gravel deposition is due to the interplay between flexure and loading: the mass deposited increases accommodation space and balances the ratio of accommodation to supply. If instead flexure where ignored, sediment supply would temporarily exceed accommodation space, leading to the deposition of a conglomeratic sheet. In the south of the Junggar Basin, the Cenozoic series display two retrogradation-progradation cycles. Within these cycles, the progradation trends from fine to coarse grains is oldest closest to the mountain belt and much more younger in the distal regions. This time-transgressive behaviour is more easily explained through a change in tectonic driven uplift, where the progradation of coarse material

  2. Georgia Basin-Puget Sound Airshed Characterization Report 2014

    EPA Science Inventory

    The Georgia Basin - Puget Sound Airshed Characterization Report, 2012 was undertaken to characterize the air quality within the Georgia Basin/Puget Sound region,a vibrant, rapidly growing, urbanized area of the Pacific Northwest. The Georgia Basin - Puget Sound Airshed Characteri...

  3. Large Igneous Provinces of the Central Asia: data on geochronology, geochemistry and petrology of the Tien Shan and Junggar basaltic complexes

    NASA Astrophysics Data System (ADS)

    Simonov, V.; Mikolaichuk, A.

    2012-04-01

    During last years Large Igneous Provinces of the Central Asia were an object of steadfast attention of researchers. It was established that on a formation and development of continental earth crust a great influence was rendered by deep magmatic systems of mantle plumes of various age. Undoubtedly that these global processes of basaltic magmatism had in many respects crucial importance for ecology, climate and life development. Our researches of magmatic associations of the Tien Shan and Junggar have allowed to accumulate a considerable volume of new data on geochronology, geochemistry and physico-chemical parameters of petrogenesis of within-plate basaltic complexes of the Central Asia, which area of distribution covers territory over than 285000 km2. Analysis with the help of 40Ar/39Ar method has shown that the basaltic complexes of the Tien Shan have Cretaceous-Paleogene age (61-76 Ma). Basalts of the Southeast Kazakhstan (North Tien Shan) corresponds to Paleozoic age: 305-312 Ma. Rather close values of 40Ar/39Ar data are received for basalts of the Altynemel Ridge (South Junggar) - 282 Ma. Isotope 40Ar/39Ar dating of basalts of the Alakol site (Junggar) has shown Mesozoic age (186-198 Ma). As a whole, the carried out researches testify to formation of Tien Shan and Junggar within-plate basalt complexes as a result of influence of three plumes, operating in various time: Tarim (282-312 Ma), Junggar (186-198 Ma) and Tien Shan (61-76 Ma). Data on petrochemistry, geochemistry of trace and rare-earth elements and mineralogy shows an enriched plume characteristics (close to OIB) of Mesozoic-Cenozoic basalts and presence of group of Paleozoic rocks close to continental and oceanic plateau basalts. As a whole, successive evolution in time of geodynamics of within-plate basalt magmatism of Tien Shan and Junggar is established. Paleozoic - plateau basaltic magmatism like Siberian traps or oceanic plateau basalts of Ontong Java. Mesozoic - development of more local hot

  4. Pacific Northwest geothermal - Review and outlook

    NASA Astrophysics Data System (ADS)

    Youngquist, W.

    1980-11-01

    Activities associated with geothermal exploration and development in the states of Idaho, Oregon, and Washington are reviewed. A geothermal electric plant on the Raft River is almost operational. Tests for space heating projects at Rexburg and in the City of Boise continue. The State of Oregon conducts its regional temperature gradient drilling program, and a number of shallow wells were drilled in 1979 and 1980. Deep well drilling (projected to 5,000 to 7,000 ft.) is pursued at Mount Hood. The eruption of Mount St. Helens has increased interest in the geothermal resources in Washington. A study of the warm and hot water potential on the northwest flank of Mount Ranier is negotiated. Possible space heating sources in 22 cities, towns, and hamlets in the Columbia Basin have been identified. Deleterious environmental impact on the forest regions of the Pacific Northwest is one reason for the Federal leasing problems. The electric power situation will be critical in the Northwest in 1983, as no additional power will probably be available to utilities from the Bonneville Power Administration. Indigenous U.S. energy sources can be developed and exploration activity can be increased if federal lease processing is greatly expedited.

  5. Geochemical effects of CO2 injection on produced water chemistry at an enhanced oil recovery site in the Permian Basin of northwest Texas, USA: Preliminary geochemical and Li isotope results

    NASA Astrophysics Data System (ADS)

    Pfister, S.; Gardiner, J.; Phan, T. T.; Macpherson, G. L.; Diehl, J. R.; Lopano, C. L.; Stewart, B. W.; Capo, R. C.

    2014-12-01

    Injection of supercritical CO2 for enhanced oil recovery (EOR) presents an opportunity to evaluate the effects of CO2 on reservoir properties and formation waters during geologic carbon sequestration. Produced water from oil wells tapping a carbonate-hosted reservoir at an active EOR site in the Permian Basin of Texas both before and after injection were sampled to evaluate geochemical and isotopic changes associated with water-rock-CO2 interaction. Produced waters from the carbonate reservoir rock are Na-Cl brines with TDS levels of 16.5-34 g/L and detectable H2S. These brines are potentially diluted with shallow groundwater from earlier EOR water flooding. Initial lithium isotope data (δ7Li) from pre-injection produced water in the EOR field fall within the range of Gulf of Mexico Coastal sedimentary basin and Appalachian basin values (Macpherson et al., 2014, Geofluids, doi: 10.1111/gfl.12084). Pre-injection produced water 87Sr/86Sr ratios (0.70788-0.70795) are consistent with mid-late Permian seawater/carbonate. CO2 injection took place in October 2013, and four of the wells sampled in May 2014 showed CO2 breakthrough. Preliminary comparison of pre- and post-injection produced waters indicates no significant changes in the major inorganic constituents following breakthrough, other than a possible drop in K concentration. Trace element and isotope data from pre- and post-breakthrough wells are currently being evaluated and will be presented.

  6. Proceedings from a Workshop on Ecological Carrying Capacity of Salmonids in the Columbia River Basin : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 3 of 4, Final Report.

    SciTech Connect

    Johnson, Gary E.; Neitzel, D.A.; Mavros, William V.

    1996-05-01

    This report contains the proceedings of a workshop held during 1995 in Portland, Oregon. The objective of the workshop was to assemble a group of experts that could help us define carrying capacity for Columbia River Basin salmonids. The workshop was one activity designed to answer the questions asked in Measure 7.1A of the Council`s Fish and Wildlife Program. Based, in part, on the information we learned during the workshop we concluded that the approach inherent in 7.1A will not increase understanding of ecology, carrying capacity, or limiting factors that influence salmon under current conditions. Measure 7.1A requires a definition of carrying capacity and a list of determinants (limiting factors) of capacity. The implication or inference then follows that by asking what we know and do not know about the determinants will lead to research that increases our understanding of what is limiting salmon survival. It is then assumed that research results will point to management actions that can remove or repair the limiting factors. Most ecologists and fisheries scientists that have studied carrying capacity clearly conclude that this approach is an oversimplification of complex ecological processes. To pursue the capacity parameter, that is, a single number or set of numbers that quantify how many salmon the basin or any part of the basin can support, is meaningless by itself and will not provide useful information.

  7. Cenozoic basin development in Hispaniola

    SciTech Connect

    Mann, P.; Burke, K.

    1984-04-01

    Four distinct generations of Cenozoic basins have developed in Hispaniola (Haiti and Dominican Republic) as a result of collisional or strike-slip interactions between the North America and Caribbean plates. First generation basins formed when the north-facing Hispaniola arc collided with the Bahama platform in the middle Eocene; because of large post-Eocene vertical movements, these basins are preserved locally in widely separated areas but contain several kilometers of arc and ophiolite-derived clastic marine sediments, probably deposited in thrust-loaded, flexure-type basins. Second generation basins, of which only one is exposed at the surface, formed during west-northwesterly strike-slip displacement of southern Cuba and northern Hispaniola relative to central Hispaniola during the middle to late Oligocene; deposition occurred along a 5-km (3-mi) wide fault-angle depression and consisted of about 2 km (1 mi) of submarine fan deposits. Third generation basins developed during post-Oligocene convergent strike-slip displacement across a restraining bend formed in central Hispaniola; the southern 2 basins are fairly symmetrical, thrust-bounded ramp valleys, and the third is an asymmetrical fault-angle basin. Fourth generation basins are pull-aparts formed during post-Miocene divergent strike-slip motion along a fault zone across southern Hispaniola. As in other Caribbean areas, good source rocks are present in all generations of basins, but suitable reservoir rocks are scarce. Proven reservoirs are late Neogene shallow marine and fluvial sandstones in third generation basins.

  8. Andes Altiplano, Northwest, Argentina

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This view of the Andean Altiplano in northwest Argentina (25.5S, 68.0W) is dominated by heavily eroded older and inactive volcano peaks. Snow is more apparent on the south faces of the slopes where the sunlight is less direct and therefore, cooler. The Altiplano is a high altitude cold desert like the Tibetan Plateau but smaller in area. It is the inland extension of the hyperarid Atacama Desert of the west coast of South America.

  9. In situ LA-MC-ICP-MS U-Pb geochronology of igneous rocks in the Ashele Basin, Altay orogenic belt, northwest China: Constraints on the timing of polymetallic copper mineralization

    NASA Astrophysics Data System (ADS)

    Yang, Fuquan; Liu, Feng; Li, Qiang; Geng, Xinxia

    2014-01-01

    The Altay orogenic belt of Kazakhstan hosts a world-class polymetallic copper volcanogenic massive sulfide (VMS) metallogenic belt, and the eastern margin of this belt extends into the southern Chinese Altay. The Ashele Basin is located at the western end of the Chinese Altay and borders Kazakhstan. The basin hosts the large Ashele copper-zinc deposit, which is a typical VMS deposit and the largest deposit in the Ashele Basin, and it hosts the subvolcanic-hosted medium-sized Sarsuk polymetallic gold deposit. Both of these deposits are hosted in the Ashele Formation volcanic sequence. The Ashele copper-zinc orebodies are stratabound orebodies located between basalt and tuff units, and were formed during exhalative sediment deposition; in comparison, the Sarsuk gold-copper-lead-zinc orebodies are hosted by rhyolite porphyry that contains disseminated, veinlet, and veinlet-stockwork ore that formed during intrusion of the rhyolite porphyry. This study presents new zircon LA-MC-ICP-MS U-Pb analyses of six volcanic and subvolcanic units, and dikes associated with the Sarsuk and Ashele deposits. The ore-bearing rhyolite porphyry, diabase dike, basalt, tuff, and dacite porphyry samples analyzed during this study yielded ages of 382.0-382.8, 381.7, 388.2, 387.0, and 379.4 Ma, respectively. These data indicate that the Ashele Formation formed during the Early-Mid-Devonian (375-402 Ma), whereas the Ashele copper-zinc deposit formed during the Middle Devonian (388-387 Ma) and the Sarsuk polymetallic copper-gold deposit formed during the latest Middle Devonian (382 Ma). Inherited zircons within the six samples analyzed during this study yielded U-Pb ages of 618-2294 Ma, suggesting the presence of Precambrian crystalline basement within the Altay orogenic belt.

  10. Buried-euxenic-basin model sets Tarim basin potential

    SciTech Connect

    Hsu, K.J. )

    1994-11-28

    The Tarim basin is the largest of the three large sedimentary basins of Northwest China. The North and Southwest depressions of Tarim are underlain by thick sediments and very thin crust. The maximum sediment thickness is more than 15 km. Of the several oil fields of Tarim, the three major fields were discovered during the last decade, on the north flank of the North depression and on the Central Tarim Uplift. The major targets of Tarim, according to the buried-euxenic-basin model, should be upper Paleozoic and lower Mesozoic reservoirs trapping oil and gas condensates from lower Paleozoic source beds. The paper describes the basin and gives a historical perspective of exploration activities and discoveries. It then explains how this basin can be interpreted by the buried-euxenic-basin model. The buried-euxenic-basin model postulates four stages of geologic evolution: (1) Sinian and early Paleozoic platform sedimentation on relic arcs and deep-marine sedimentation in back-arc basins in Xinjiang; (2) Late Paleozoic foreland-basin sedimentation in north Tarim; (3) Mesozoic and Paleogene continental deposition, subsidence under sedimentary load; and (4) Neogene pull-apart basin, wrench faulting and extension.

  11. 18. VIEW OF SETTLING BASIN FROM UPSTREAM TRESTLE, SHOWING BULKHEAD ...

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

    18. VIEW OF SETTLING BASIN FROM UPSTREAM TRESTLE, SHOWING BULKHEAD ON RIGHT AND SAND BANK ON LEFT, LOOKING NORTHWEST - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  12. Northwest corner of Wyoming

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A near vertical view of the snow-covered northwest corner of Wyoming (43.5N, 109.5W), as seen from the Skylab space station in Earth orbit. A small portion of Montana and Idaho is in this photograph, also. The dark area is Yellowstone National Park. The largest body of water is Yellowstone Lake. The elongated range in the eastern part of the picture is the Big Horn Moutains. The Wind River Range is at the bottom center. The Grand Teton National Park area is almost straight south of Yellowstone Lake. Approximately 30 per cent of the State of Wyoming can be seen in this photograph.

  13. Northwest Area Science

    USGS Publications Warehouse

    Fuentes, Tracy L.; van Heeswijk, Marijke; Grossman, Eric E.

    2010-01-01

    Northwest Area Facts * Population about 12 million * 43 federally recognized Tribes * Hydropower provides about two-thirds of electricity supply * 78 federally listed threatened and endangered species * 12 active or potentially active volcanoes * Columbia River system drains more than 260,000 square miles, an area about the size of Texas * More than 175 square miles covered by glaciers * More than 900 miles of Pacific Ocean coastline * More than 2,300 miles of greater Puget Sound coastline * Some forests store more carbon per unit area than any other area in the world, including the tropics * 51 percent federal lands * Significant lead, zinc, silver, and phosphate deposits

  14. Holocene paleoenviroments of northwest Iowa

    SciTech Connect

    Baker, R.G.; Bettis, E.A. III; Schwert, D.P.

    1996-05-01

    This paper presents the biotic, sedimentary, geomorphic, and climatic history of the upper part of the Roberts Creek Basin, northeastern Iowa for the late-glacial and Holocene, and compares these records with a C-O isotopic sequence from Coldwater Cave, 60 km northwest of Roberts Creek. the biotic record (pollen, vascular plant and bryophyte macrofossils, and insects) is preserved in floodplain alluvium that underlies three constructional surfaces separated by low scarps. Each surface is underlain by a lithologically and temporally distinct alluvial fill. The highest surface is underlain by the Gunder Member of the Deforest Formation, dating from 11,000 to 4000 yr BP; beneath the intermediate level is the Roberts Creek Member, dating from 4000 to 400 yr BP; and the lowest level is underlain by the Camp Creek Member, deposited during the last 380 yr. Pollen and plant macrofossils in the alluvial fill show that a typical late-glacial spruce forest was replaced by Quercus and Ulmus in the early Holocene. This early-to-middle Holocene forest became dominated by medic elements such as Acer saccharum, Tila americana, Ostyra virginiana, and Carpinus caroliniana as late as 5500 yr BP; in contrast, the closest sites to the west and north were at their warmest and driest were covered by prairie vegetation between 6500 and 5500 yr BP. After 5500 yr BP, the forest in the roberts Creek area was replaced by prairie, as indicated by a rich assemblage of plant macrofossils, although only Ambrosia and Poaceae became abundant in the pollen record. The return of Quercus {approx} 3000 BP (while nonarboreal pollen percentages remained relatively high) indicates the oak savanna prevailed with little change until settlement time. 83 refs., 17 figs., 5 tabs.

  15. Zircon U-Pb ages and Hf isotopes of the Askot klippe, Kumaun, northwest India: Implications for Paleoproterozoic tectonics, basin evolution and associated metallogeny of the northern Indian cratonic margin

    NASA Astrophysics Data System (ADS)

    Mandal, Subhadip; Robinson, Delores M.; Kohn, Matthew J.; Khanal, Subodha; Das, Oindrila; Bose, Sukhanjan

    2016-04-01

    Throughout the Himalayan thrust belt, klippen of questionable tectonostratigraphic affinity occur atop Lesser Himalayan rocks. Integrated U-Pb ages, Hf isotopic, and whole rock trace element data establish that the Askot klippe, in northwest India, is composed of Paleoproterozoic lower Lesser Himalayan rocks, not Greater Himalayan rocks, as previously interpreted. The Askot klippe consists of 1857 ± 19 Ma granite-granodiorite gneiss, coeval 1878 ± 19 Ma felsic volcanic rock, and circa 1800 Ma Berinag quartzite, representing a small vestige of a Paleoproterozoic (circa 1850 Ma) continental arc, formed on northern margin of the north Indian cratonic block. Detrital zircon from Berinag quartzite shows ɛHf1850 Ma values between -9.6 and -1.1 (an average of -4.5) and overlaps with ɛHf1850 Ma values of the Askot klippe granite-granodiorite gneiss (-5.5 to -1.2, with an average of -2.7) and other Paleoproterozoic arc-related Lesser Himalayan granite gneisses ( -4.8 to -2.2, with an average of -4.0). These overlapping data suggest a proximal arc source for the metasedimentary rocks. Subchondritic ɛHf1850 Ma values (-5.5 to -1.2) of granite-granodiorite gneiss indicate existence of a preexisting older crust that underwent crustal reworking at circa 1850 Ma. A wide range of ɛHf1850 Ma values in detrital zircon (-15.0 to -1.1) suggests that a heterogeneous crustal source supplied detritus to the northern margin of India. These data, as well as the presence of a volcanogenic massive sulphide deposit within the Askot klippe, are consistent with a circa 1800 Ma intra-arc extensional environment.

  16. Pacific Northwest: paradise lost

    SciTech Connect

    Thomas, W.V.

    1980-04-18

    An influx of new residents to the Pacific Northwest is changing social patterns and is endangering the region's valued wilderness and resources. A growing population and a feeling that the national govenment is more exploitive than conserving of its resources combines with a political tension between progressive populism and conservative Mormon influences to make residents wary of either newcomers or new prosperity. The abundant hydro power is threatened as power demand increases and utilities, industries, and the state and local governments compete for their fair share. A plan to restructure the Bonneville Power Administration (BPA) has been introduced in Congress to give it a single appointed administrator with the authority to decide how power will be distributed and which new power sources to develop. Concern about the two national nuclear waste repositories at Hanford and Idaho Falls led to a six-month moratorium at Hanford to warn the government that the site was not intended to be a permanent solution. A legislative proposal to set up regional nuclear parks will not relieve the Pacific Northwest's problems for some time. Leaders blame the policymakers for looking on the area as too remote and underpopulated to worry about. 18 references (DCK)

  17. Northwest Climate Risk Assessment

    NASA Astrophysics Data System (ADS)

    Mote, P.; Dalton, M. M.; Snover, A. K.

    2012-12-01

    As part of the US National Climate Assessment, the Northwest region undertook a process of climate risk assessment. This process included an expert evaluation of previously identified impacts, their likelihoods, and consequences, and engaged experts from both academia and natural resource management practice (federal, tribal, state, local, private, and non-profit) in a workshop setting. An important input was a list of 11 risks compiled by state agencies in Oregon and similar adaptation efforts in Washington. By considering jointly the likelihoods, consequences, and adaptive capacity, participants arrived at an approximately ranked list of risks which was further assessed and prioritized through a series of risk scoring exercises to arrive at the top three climate risks facing the Northwest: 1) changes in amount and timing of streamflow related to snowmelt, causing far-reaching ecological and socioeconomic consequences; 2) coastal erosion and inundation, and changing ocean acidity, combined with low adaptive capacity in the coastal zone to create large risks; and 3) the combined effects of wildfire, insect outbreaks, and diseases will cause large areas of forest mortality and long-term transformation of forest landscapes.

  18. Tectonic framework of Turkish sedimentary basins

    SciTech Connect

    Yilmaz, P.O. )

    1988-08-01

    Turkey's exploration potential primarily exists in seven onshore (Southeast Turkey platform, Tauride platform, Pontide platform, East Anatolian platform, Interior, Trace, and Adana) basins and four offshore (Black Sea, Marmara Sea, Aegean Sea, and Mediterranean Sea) regional basins formed during the Mesozoic and Tertiary. The Mesozoic basins are the onshore basins: Southeast Turkey, Tauride, Pontide, East Anatolian, and Interior basins. Due to their common tectonic heritage, the southeast Turkey and Tauride basins have similar source rocks, structural growth, trap size, and structural styles. In the north, another Mesozoic basin, the Pontide platform, has a much more complex history and very little in common with the southerly basins. The Pontide has two distinct parts; the west has Paleozoic continental basement and the east is underlain by island-arc basement of Jurassic age. The plays are in the upper Mesozoic rocks in the west Pontide. The remaining Mesozoic basins of the onshore Interior and East Anatolian basins are poorly known and very complex. Their source, reservoir, and seal are not clearly defined. The basins formed during several orogenic phases in mesozoic and Tertiary. The Cenozoic basins are the onshore Thrace and Adana basins, and all offshore regional basins formed during Miocene extension. Further complicating the onshore basins evolution is the superposition of Cenozoic basins and Mesozoic basins. The Thrace basin in the northwest and Adana basin in the south both originate from Tertiary extension over Tethyan basement and result in a similar source, reservoir, and seal. Local strike-slip movement along the North Anatolian fault modifies the Thrace basin structures, influencing its hydrocarbon potential.

  19. Geodynamic scenario and structural styles of Mesozoic and Cenozoic basins in China

    SciTech Connect

    Hefu, L.

    1986-04-01

    The continental lithosphere of China is situated at the junction of the Marginal-Pacific and Tethys-Himalayan tectonic domains. The most manifest tectonic movements responsible for the deformation of the continental lithosphere of China are taphrogenic, collisional, and shearing. These movements played an important role in the Mesozoic and Cenozoic tectonic evolution of China and formed various types of Mesozoic and Cenozoic basins in China. The Marginal-Pacific crust in eastern China was attenuated by rifting and developed north-northeast-trending Mesozoic and Cenozoic basins, e.g., the Songliao, Bohai Bay, and Jianghan basins. Rifting mainly followed preexisting lineaments or shear zones in the basement. Then basin-range (graben-horst) structures and large fault-bounded basins developed. Extensional structural styles have prevailed in Mesozoic and Cenozoic basins in eastern China, with listric faults and tilted blocks in the basement, and detached faults, growth faults, and rollover anticlines or drape folds in the cover rocks. These structures are favorable for hydrocarbon accumulation; thus, the famous Daqing and Zhongyuan oil fields formed in Songliao basin and Bohai Bay basin, respectively. In western China the continental crust thickened by collision and formed a series of Mesozoic and Cenozoic intermontane and foreland basins, such as the Junggar (Dzungaria), Tarim, and Qaidam basins. Contraction structural styles are predominant in Mesozoic and Cenozoic basins in western China, with shortened fault blocks and ramps in basement, and thrust faults and folds in the cover rocks. The Kelamayi and Laojunmiao oil fields formed in these compressional basins. 22 figures, 1 table.

  20. Northwest Education, 1998-1999.

    ERIC Educational Resources Information Center

    Sherman, Lee, Ed.; Kneidek, Tony, Ed.

    1999-01-01

    Volume 4 of "Northwest Education" contains four issues. Each issue has a theme and typically consists of an opening review article on current trends and research related to the theme, followed by articles on exemplary schools or programs in the Northwest, promising practices, outstanding teachers, or suggestions for program implementation or staff…

  1. Physics Northwest: An Academic Alliance

    ERIC Educational Resources Information Center

    Hicks, James L.

    2007-01-01

    It's a weekday in mid-October, late at night and with another teaching assignment not far below the horizon. Yet 40 teachers are laughing, joking, and sharing in the fun that is associated with physics teaching. The event: a Physics Northwest (PNW) meeting, an organization that is in its 20th year and thriving. "Physics Northwest meetings are not…

  2. Northwest Education, 2002-2003.

    ERIC Educational Resources Information Center

    Sherman, Lee, Ed.; Boss, Suzie, Ed.; Weeks, Denise Jarrett, Ed.

    2003-01-01

    This document contains the four issues of Northwest Education published during the 2002-03 school year. Issue themes are: (1) "Closing the Gap: How Northwest Schools Are Raising Minority Achievement"; (2) "Focus on Writing"; (3) "The Hidden Disability: When Bright Children Struggle To Learn"; and (4) "Discoveries in Learning: Lessons from Lewis &…

  3. Methane origin and oxygen-fugacity evolution of the Baogutu reduced porphyry Cu deposit in the West Junggar terrain, China

    NASA Astrophysics Data System (ADS)

    Shen, Ping; Pan, HongDi

    2015-12-01

    Most porphyry copper deposits worldwide contain magnetite, hematite, and anhydrite in equilibrium with hypogene copper-iron sulfides (chalcopyrite, bornite) and have fluid inclusions with CO2 >> CH4 that are indicative of high fO2. In contrast, the Baogutu porphyry Cu deposit in the West Junggar terrain (Xinjiang, China) lacks hematite and anhydrite, contains abundant pyrrhotite and ilmenite in equilibrium with copper-iron sulfides (chalcopyrite), and has fluid inclusions with CH4 >> CO2 that are indicative of low fO2. The mineralized intrusive phases at Baogutu include the main-stage diorite stock and minor late-stage diorite porphyry dikes. The main-stage stock underwent fractional crystallization and country-rock assimilation-contamination, and consists of dominant diorite and minor gabbro and tonalite porphyry. The country rocks contain organic carbons (0.21-0.79 wt.%). The δ13CvPDB values of the whole rocks (-23.1 to -25.8 ‰) in the wall rocks suggest a sedimentary organic carbon source. The δ13CvPDB values of CH4 (-28.2 to -36.0 ‰) and CO2 (-6.8 to -20.0 ‰) in fluid inclusions require an organic source of external carbon and equilibration of their Δ13CCO2-CH4 values (8.2-25.0 ‰) at elevated temperatures (294-830 °C) suggesting a significant contribution of thermogenic CH4. Mineral composition data on the main-stage intrusions, such as clinopyroxene, hornblende, biotite, magnetite, ilmenite, sphene, apatite, and pyrrhotite, suggest that the primary magma at Baogutu was oxidized and became reduced after emplacement by contamination with country rocks. Mineral compositions and fluid inclusion gas compositions suggest that the redox state of the system evolved from log fO2 > FMQ + 1 in the magma stage, to log fO2 < FMQ as a consequence of country rocks assimilation-contamination, to log fO2 > FMQ in the hydrothermal stage. Though oxidized magma was emplaced initially, assimilation-contamination of carbonaceous country rocks decreased its fO2 such that

  4. Caribbean basin framework, 3: Southern Central America and Colombian basin

    SciTech Connect

    Kolarsky, R.A.; Mann, P. )

    1991-03-01

    The authors recognize three basin-forming periods in southern Central America (Panama, Costa Rica, southern Nicaragua) that they attempt to correlate with events in the Colombian basin (Bowland, 1984): (1) Early-Late Cretaceous island arc formation and growth of the Central American island arc and Late Cretaceous formation of the Colombian basin oceanic plateau. During latest Cretaceous time, pelagic carbonate sediments blanketed the Central American island arc in Panama and Costa Rica and elevated blocks on the Colombian basin oceanic plateau; (2) middle Eocene-middle Miocene island arc uplift and erosion. During this interval, influx of distal terrigenous turbidites in most areas of Panama, Costa Rica, and the Colombian basin marks the uplift and erosion of the Central American island arc. In the Colombian basin, turbidites fill in basement relief and accumulate to thicknesses up to 2 km in the deepest part of the basin. In Costa Rica, sedimentation was concentrated in fore-arc (Terraba) and back-arc (El Limon) basins; (3) late Miocene-Recent accelerated uplift and erosion of segments of the Central American arc. Influx of proximal terrigenous turbidites and alluvial fans in most areas of Panama, Costa Rica, and the Colombian basin marks collision of the Panama arc with the South American continent (late Miocene early Pliocene) and collision of the Cocos Ridge with the Costa Rican arc (late Pleistocene). The Cocos Ridge collision inverted the Terraba and El Limon basins. The Panama arc collision produced northeast-striking left-lateral strike-slip faults and fault-related basins throughout Panama as Panama moved northwest over the Colombian basin.

  5. Atlantic marginal basins of Africa

    SciTech Connect

    Moore, G.T.

    1988-02-01

    The over 10,000-km long Atlantic margin of Africa is divisible into thirty basins or segments of the margin that collectively contain over 18.6 x 10/sup 6/ km/sup 3/ of syn-breakup and post-breakup sediments. Twenty of these basins contain a sufficiently thick volume of sediments to be considered prospects. These basins lie, at least partially, within the 200 m isobath. The distribution of source rocks is broad enough to give potential to each of these basins. The sedimentation patterns, tectonics, and timing of events differ from basin to basin and are related directly to the margin's complex history. Two spreading modes exist: rift and transform. Rifting dates from Late Triassic-Early Jurassic in the northwest to Early Cretaceous south of the Niger Delta. A complex transform fault system separated these two margins. Deep-water communication between the two basins became established in the middle Cretaceous. This Mesozoic-Cenozoic cycle of rifting and seafloor spreading has segmented the margin and where observable, basins tend to be bounded by these segments.

  6. Global warming: A Northwest perspective

    SciTech Connect

    Scott, M.J.; Counts, C.A.

    1990-02-01

    The Northwest Power Planning Council convened a symposium in Olympia, Washington, on the subject of global climate change ( the greenhouse effect'') and its potential for affecting the Pacific Northwest. The symposium was organized in response to a need by the Power Council to understand global climate change and its potential impacts on resource planning and fish and wildlife planning for the region, as well as a need to understand national policy developing toward climate change and the Pacific Northwest's role in it. 40 figs., 15 tabs.

  7. Space Science Network Northwest

    NASA Astrophysics Data System (ADS)

    Lutz, J.

    2002-12-01

    Space Science Network Northwest (S2N2) is a new NASA Office of Space Science Education Broker/Facilitator that serves the states of Alaska, Hawaii, Idaho, Montana, Oregon, Washington and Wyoming. The headquarters of S2N2 is at the University of Washington in Seattle and the Director is Julie Lutz (206-543-0214; nasaerc@u.washington.edu). Each state has an S2N2 representative. Their contact information can be found on the Web site (www.s2n2.org) or by contacting Julie Lutz. The purpose of S2N2 is to form and nurture partnerships between space scientists and others (K-12 teachers, schools and districts, museums, planetariums, libraries, organizations such as Girl Scouts, amateur astronomy clubs, etc.). S2N2 can help space scientists come up with appropriate activities and partners for education and public outreach proposals and projects. S2N2 also provides information and advice about education materials and programs that are available from all of the Office of Space Science missions and scientific forums (Solar System Exploration, Structure and Evolution of the Universe, Sun-Earth Connection, Astronomical Search for Origins).

  8. 75 FR 64752 - Amended Columbia River Basin Fish and Wildlife Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

    ... POWER AND CONSERVATION PLANNING COUNCIL Amended Columbia River Basin Fish and Wildlife Program AGENCY... Council's Columbia River Basin Fish and Wildlife Program. SUMMARY: Pursuant to Section 4(h) of the Northwest Power Act, the Council has amended its Columbia River Basin Fish and Wildlife Program to add...

  9. Abiogenic Fischer-Tropsch synthesis of methane at the Baogutu reduced porphyry copper deposit, western Junggar, NW-China

    NASA Astrophysics Data System (ADS)

    Cao, MingJian; Qin, KeZhang; Li, GuangMing; Evans, Noreen J.; Jin, LuYing

    2014-09-01

    Methane is widely developed in hydrothermal fluids from reduced porphyry copper deposits, but its origin remains enigmatic. The occurrence of methane in fluid inclusions at the Late Carboniferous Baogutu reduced porphyry copper deposit in western Junggar, Xinjiang, NW-China, presents an excellent opportunity to address this problem. A systematic study including fluid inclusion Laser-Raman and CO2-CH4 carbon isotope analyses, igneous and hydrothermal mineral H-O isotope analyses, and in situ major, trace element and Sr isotopic analyses of hydrothermal epidote was conducted to constrain the origin of CH4 and CH4-rich fluids. The δ2H and δ18O of water in equilibrium with igneous biotite ranges from -65.0‰ to -66.0‰ and +7.2‰ to +7.4‰, respectively, indicating notable degassing of probably supercritical fluids in the magma chamber. The wide range of δ2H (-58.0‰ to -107.0‰, n = 23) for water within quartz suggests the existence of significant hydrothermal fluid boiling. Water-rock interaction is the most likely mechanism leading to the wide range of δ18O values for water in vein quartz with water/rock ratios (wt.% in O) of 0.15 to 0.75 and 0.13 to 0.46 for a closed and open system, respectively. Detailed Laser-Raman analyses indicate CO2 in apatite included in granodiorite porphyry phenocrystic biotite that records the carbon species of the early stage magmatic stage, whereas later hydrothermal fluids containing CH4 with trace or without CO2 are found in inclusions of vein quartz. We propose that CH4 is probably transformed from CO2 by Fischer-Tropsch type reactions at 500 °C, assumed from CO2-CH4 C isotope equilibrium. The (87Sr/86Sr)i of hydrothermal epidote yields values of 0.70369-0.70404, consistent with that reported for the whole rocks. The δ13CCH4 (-28.6‰ to -22.6‰) and δ2HCH4 (-108.0‰ to -59.5‰) are characteristic of abiogenic methane. The measured δ13CCO2 shows a slightly depleted 13C (-13.5‰ to -7.2‰) relative to upper mantle

  10. Perspective of gas exploration in Ying-Qiong Basin

    SciTech Connect

    He, Hanyi; Zhongtiang Hu )

    1996-01-01

    The Yinggehai and Qiongdongnan Basin (Ying-Qiong Basin) in the northwest part of the South China Sea is a Cenozoic sedimentary basin, which has fast-subsiding and thick sediments. The maximum Cenozoic sediments in the center part of the basin is 20,000 m. Six sets of source rocks with prevailing Type III kerogen were developed in the basin, which has a great potential for gas generation. Different types of reservoirs and traps, leading to different assemblages of source rocks, reservoirs, and cap rocks, form good gas pools. Abnormal high temperature and high pressure in the basin resulted in many mud diapirs and made the generation, migration, and accumulation of gas more colorful. Up to now, four gas fields have been discovered in the basin. A large number of anticlines and stratigraphic-lithologic traps in the basin provide an extensive area for gas exploration. The perspective of gas exploration in the basin is vast and bright.

  11. Perspective of gas exploration in Ying-Qiong Basin

    SciTech Connect

    He, Hanyi; Zhongtiang Hu

    1996-12-31

    The Yinggehai and Qiongdongnan Basin (Ying-Qiong Basin) in the northwest part of the South China Sea is a Cenozoic sedimentary basin, which has fast-subsiding and thick sediments. The maximum Cenozoic sediments in the center part of the basin is 20,000 m. Six sets of source rocks with prevailing Type III kerogen were developed in the basin, which has a great potential for gas generation. Different types of reservoirs and traps, leading to different assemblages of source rocks, reservoirs, and cap rocks, form good gas pools. Abnormal high temperature and high pressure in the basin resulted in many mud diapirs and made the generation, migration, and accumulation of gas more colorful. Up to now, four gas fields have been discovered in the basin. A large number of anticlines and stratigraphic-lithologic traps in the basin provide an extensive area for gas exploration. The perspective of gas exploration in the basin is vast and bright.

  12. Kandik basin stratigraphy, sedimentology, and structure

    SciTech Connect

    Wiley, T.J.; Howell, D.G.; Kauffman-Linam, L.; Boundy-Sanders, S.; Murray, R.W.; Jones, D.L.

    1987-05-01

    East-central Alaska's Kandik basin is a structural remnant of a larger Permian to Cretaceous basin. Permian shallow-water Tahkandit Limestone and Step Conglomerate at the base of the sequence rest unconformably on Paleozoic chert-pebble conglomerate, siliceous shale, and limestone. These Permian rocks are overlain by Triassic to Lower Cretaceous open-ocean Glenn Shale, which grades upward into Lower Cretaceous (Valanginian) hummocky cross-bedded (outer shelf to upper slope) Keenan Quartzite. The quartzite grades upward into fine-grained north-northeast-flowing turbidites of the Biederman Argillite (undated). East-northeast-flowing pebbly turbidites of the Kathul Graywacke (undated) overlie Biederman strata. Locally, Cretaceous (Albian and younger) through Paleogene nonmarine rocks unconformably overlie the Kandik basin sequence. The Mesozoic part of the sequence is similar to that of Manley basin, northwest Yukon Territory, and much of the North Slope. East-directed flow for Kandik basin strata may require paleogeographic reconstructions involving local to large-scale palinspastic rotations or a western source of chert detritus. Deformation of the Mesozoic sequence in Kandik basin west of the US-Canada border shows northwest-southeast shortening. Shaly units are tightly folded with well-developed cleavage striking northeast. Strikes of beds swing from northeast to east in the extreme southwestern part of the basin, suggesting clockwise rotation. Thrust faults, reverse faults, and fold axes trend east to northeast; normal faults trend northwest. These relations are all consistent with, and probably are closely related to, right slip on the west-northwest-trending Tintina fault.

  13. Caribbean basin framework, 4: Maracaibo basin, northwestern Venezuela

    SciTech Connect

    Lugo, J. )

    1991-03-01

    The Maracaibo basin is presently located in a topographic depression on the Maracaibo block, a triangular, fault-bounded block within the Caribbean-South America plate boundary of northwestern Venezuela. Intense oil exploration over the last 50 years has produced a large amount of seismic and well data that can be used to constrain four Jurassic to Recent tectonic and depositional events that affected the region: (1). Late Jurassic rift phase and subsidence along normal faults striking north-northeast across the floor of the basin; (2) Cretaceous to early Eocene subsidence recorded by shallow to deep marine carbonate and clastic rocks that thicken from south to north and completely cover Permian rocks of the Merida arch; (3) Eocene folding, thrusting, and initial reactivation of Jurassic normal faults as convergent strike-slip and reverse faults. Eocene clastic sediments are thickest in a narrow northwest-trending foredeep on the northeastern margin of the basin; (4) Late Miocene to Recent northwest-southeast convergence is marked by continued reactivation of Jurassic normal faults as reverse and left-lateral strike-slip faults, uplift of mountain ranges bordering the basin, and deposition of up to 10 km of clastic sediment.

  14. Mississippian facies relationships, eastern Anadarko basin, Oklahoma

    SciTech Connect

    Peace, H.W. ); Forgotson, J.M. )

    1991-08-01

    Mississippian strata in the eastern Anadarko basin record a gradual deepening of the basin. Late and post-Mississippian tectonism (Wichita and Arbuckle orogenies) fragmented the single large basin into the series of paired basins and uplifts recognized in the southern half of Oklahoma today. Lower Mississippian isopach and facies trends (Sycamore and Caney Formations) indicate that basinal strike in the study area (southeastern Anadarko basin) was predominantly east-west. Depositional environment interpretations made for Lower Mississippian strata suggest that the basin was partially sediment starved and exhibited a low shelf-to-basin gradient. Upper Mississippian isopach and facies trends suggest that basinal strike within the study area shifted from dominantly east-west to dominantly northwest-southeast due to Late Mississippian and Early Pennsylvanian uplift along the Nemaha ridge. Within the study area, the Chester Formation, composed of gray to dove-gray shales with interbedded limestones deposited on a carbonate shelf, thins depositionally into the basin and is thinnest at its facies boundary with the Springer Group and the upper portion of the Caney Formation. As basin subsidence rates accelerated, the southern edge of the Chester carbonate shelf was progressively drowned, causing a backstepping of the Chester Formation calcareous shale and carbonate facies. Springer Group sands and black shales transgressed northward over the drowned Chester Formation shelf.

  15. Sedimentation of shelf sandstones in Queen Formation, McFarland and Means fields, central basin platform of Permian basin

    SciTech Connect

    Malicse, A.; Mazzullo, J.; Holley, C.; Mazzullo, S.J.

    1988-01-01

    The Queen Formation is a sequence of carbonates, evaporites, and sandstones of Permian (Guadalupian) age that is found across the subsurface of the Central Basin platform of the Permian basin. The formation is a major hydrocarbon reservoir in this region, and its primary reservoir facies are porous shelf sandstones and dolomites. Cores and well logs from McFarland and Means fields (on the northwest margin of the Central Basin platform) were examined to determine the sedimentary history of the shelf sandstones.

  16. BPA Committed to Northwest Values

    SciTech Connect

    2010-09-01

    The Columbia River has been called the “crown jewel” of the Pacific Northwest. There is no question it is among the region’s greatest assets — supplying low-cost clean hydropower, making deserts bloom thanks to irrigation and providing navigation, recreation and a home for many species of fish and wildlife. The Bonneville Power Administration is proud to be a steward of this great resource. Our mission is to serve the people and environment of the Pacific Northwest. We sell wholesale power from Grand Coulee Dam and 30 other Northwest federal dams to Northwest utilities, including public utility districts, rural electric cooperatives and municipal utility departments, as well as investor-owned utilities. We operate three-fourths of the region’s high voltage transmission system that delivers that power. But, as a federal agency, we are not just a power marketer. We have public responsibilities that include, among many, promoting energy efficiency, facilitating development of renewable power, protecting fish and wildlife affected by hydro development, honoring treaty obligations to tribes and promoting a reliable energy future through collaboration and partnerships. This document describes our responsibilities to citizens in the Pacific Northwest.

  17. Irradiation of Northwest agricultural products

    SciTech Connect

    Eakin, D.E.; Tingey, G.L.

    1985-02-01

    Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect control procedures are developed and followed. Due to the recognized potential benefits of irradiation, Pacific Northwest Laboratory (PNL) is conducting this program to evaluate the benefits of using irradiation on Northwest agricultural products under the US Department of Energy (DOE) Defense Byproducts Production and Utilization Program. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

  18. Geophysical basin structure of the Cotonou (Dahomey/Benin) basin, West African Gulf of Guinea

    SciTech Connect

    Babalola, O.O. )

    1990-05-01

    The frontier Cotonou basin (or Dahomey/Benin embayment), situated west of the prolific Niger Delta basin, appears from seismic, gravity, and aeromagnetic interpretation, as a series of grabens and troughs confined on the west and east by the Romanche and the Chain fracture zones, respectively. The Keta trough of the western basin rim was formed by a 2700-m southeasterly downthrow of the Adina fault. This trough is separated by a north-northeasterly fault from the Lome-Anecho gravity high. Eastward, the arcuate Allada-Adjohon trough is abutted on its southern flank by the northwest-trending Nokue-Afowo trough and separated from the northwesterly Ikorodu trough by the 50-km-wide aeromagnetically inferred ro-Otta ridge. The Ikorodu trough is adjoined on the northwest by the Aiyetoro trough and on the southeast by the Yemoja offshore graben trending east northeast as the Seme oil-field structural trend. North of the regional northeasterly axial, gravity positive, structural divide (the continental precursor of the Charcot fracture zone) a series of half-grabens (notably the Aplahoue, Bohicon, and Keiou troughs), normal faulted eastward and downthrown in the west, dominate the landward western rim of the Cotonou basin. Graben-bounding faults control the upper valleys of the basin drainage, converge toward the regional intrabasin structural trend and continue into the Fenyi-koe fault and the Charcot fracture zone. These faults resulted from brittle dextral shear of continental crust oblique to local, preexisting north-northeast structural trends. In the eastern basin rim, preexisting north-northwest structural trends influenced the shearing stress regime to generate small, shallow, structurally bounded, east-northeast- and north-northwest trending grabens.

  19. Provenance and basin evolution, Zhada basin, southwestern Tibet

    NASA Astrophysics Data System (ADS)

    Saylor, J.; Decelles, P.; Gehrels, G.; Kapp, P.

    2007-12-01

    The Zhada basin is a late Miocene - Pliocene intermontane basin situated at high elevations in the Himalayan hinterland. The fluvial and lacustrine sediments of the Zhada formation are undeformed and sit in angular unconformity above the deformed Tethyan Sedimentary Sequence (TSS). The basin sits just south of the Indus suture in a structural position occupied elsewhere in the Himalayan orogen by some of the highest mountains on earth, including Everest. The occurrence of a basin at this location demands explanation. Currently, the Sutlej River flows parallel to the structural grain of the Himalaya, westward through the basin, towards the Leo Pargil (Qusum) range. Near the range front it takes a sharp southward turn, cuts across the structural grain of the Himalaya and out into the Gangetic foreland. Palaeocurrent indicators in the lower part of the Zhada formation show that the basin originated as a northwest flowing axial river. Palaeocurrent indicators are consistently northwest oriented, even to within to within 10 km of the Leo Pargil range front in the north-western end of the basin. This implies that at the onset of sedimentation in Zhada basin the Leo Pargil range was not a barrier as it is today. In the upper part of the Zhada formation, palaeocurrent indicators are generally directed towards the centre of the basin. In the central and southern portions of the basin this indicates a transition from an axial, northwest flowing river to prograding fluvial and alluvial fans. However, in the north-western part of the basin the change between lower and upper Zhada formation involves a complete drainage reversal. This change in palaeocurrent orientation is also reflected in the detrital zircon signal from basin sediments. Low in the Zhada formation the detrital zircon signal is dominated by zircons from the Kailash (Gangdese) batholith (or associated extrusives, see below). However, higher in the sections, a local source, either from the TSS or the core of the

  20. Enhanced warming of the Northwest Atlantic Ocean under climate change

    NASA Astrophysics Data System (ADS)

    Saba, Vincent S.; Griffies, Stephen M.; Anderson, Whit G.; Winton, Michael; Alexander, Michael A.; Delworth, Thomas L.; Hare, Jonathan A.; Harrison, Matthew J.; Rosati, Anthony; Vecchi, Gabriel A.; Zhang, Rong

    2016-01-01

    The Intergovernmental Panel on Climate Change (IPCC) fifth assessment of projected global and regional ocean temperature change is based on global climate models that have coarse (˜100 km) ocean and atmosphere resolutions. In the Northwest Atlantic, the ensemble of global climate models has a warm bias in sea surface temperature due to a misrepresentation of the Gulf Stream position; thus, existing climate change projections are based on unrealistic regional ocean circulation. Here we compare simulations and an atmospheric CO2 doubling response from four global climate models of varying ocean and atmosphere resolution. We find that the highest resolution climate model (˜10 km ocean, ˜50 km atmosphere) resolves Northwest Atlantic circulation and water mass distribution most accurately. The CO2 doubling response from this model shows that upper-ocean (0-300 m) temperature in the Northwest Atlantic Shelf warms at a rate nearly twice as fast as the coarser models and nearly three times faster than the global average. This enhanced warming is accompanied by an increase in salinity due to a change in water mass distribution that is related to a retreat of the Labrador Current and a northerly shift of the Gulf Stream. Both observations and the climate model demonstrate a robust relationship between a weakening Atlantic Meridional Overturning Circulation (AMOC) and an increase in the proportion of Warm-Temperate Slope Water entering the Northwest Atlantic Shelf. Therefore, prior climate change projections for the Northwest Atlantic may be far too conservative. These results point to the need to improve simulations of basin and regional-scale ocean circulation.

  1. Irradiation of northwest agricultural products

    NASA Astrophysics Data System (ADS)

    Eakin, D. E.; Tingey, G. I.

    1985-02-01

    Irradiation of food for disinfestation and preservation is increasing in importance because of increasing restrictions on various chemical treatments. Irradiation treatment is of particular interest in the Northwest because of a growing supply of agricultural products and the need to develop new export markets. Several products have, or could potentially have, significant export markets if stringent insect ocntrol procedures are developed and followed. Due to the recognized potential benefits of irradiation, this program was conducted to evaluate the benefits of using irradiation on Northwest agricultural products. Commodities currently included in the program are cherries, apples, asparagus, spices, hay, and hides.

  2. Latest Miocene to Quaternary deformation in the southern Chaiwopu Basin, northern Chinese Tian Shan foreland

    NASA Astrophysics Data System (ADS)

    Lu, Honghua; Wang, Zhen; Zhang, Tianqi; Zhao, Junxiang; Zheng, Xiangmin; Li, Youli

    2015-12-01

    Basinward propagation of fold and thrust belts is a crucial geological process accommodating Cenozoic crustal shortening within the India-Eurasia collision zone. Anticlinal growth strata in the southern Chaiwopu Basin (a piggyback basin) of the northern Chinese Tian Shan foreland record basinward encroachment of the Tian Shan along the Junggar Frontal Thrust Fault. A new magnetostratigraphic section constrains the onset of syntectonic growth strata at circa 6.4 Ma and suggests synchronous basinward thrusting and propagation of the Tian Shan. The intense alluviation in the southern Chaiwopu Basin ceased at circa 0.55 Ma due to significant anticlinal growth and its resultant river incision. More recent anticlinal growth and deformation during the late Quaternary are revealed by folded river terraces developing across the anticline. The terrace height profile indicates that terrace T1H has been vertically offset about 0.6 m by thrust faulting since its formation at about 7 Ka. The stratigraphic and geomorphic data presented in this work are helpful to understand the initiation of thrust-related folding, as well as aggradation and subsequent incision, in foreland basins of the Tian Shan in relation to the India-Asia collision.

  3. DELUGE AND WATER RECLAMATION BASIN BELOW TEST STAND 1A. Looking ...

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

    DELUGE AND WATER RECLAMATION BASIN BELOW TEST STAND 1-A. Looking north northwest - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Flame Deflector Water System, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  4. China, JNOC start exploration in Tarim basin

    SciTech Connect

    Not Available

    1992-06-15

    This paper reports that a joint venture of China National Oil and Natural Gas Corp and Japan National Oil Corp (JNOC) has begun exploration in Northwest China's remote Tarim basin in Xinjiang Uygur Autonomous Region. That marks the first time China has allowed a foreign oil company to participate in exploration of the highly prospective basin. China pins much of its hope for the future on the Tarim basin as production declines from its older, mainstay fields in the east and offshore results have proved largely disappointing. The Chinese-Japanese combine began operations in the southwest part of the 560,000 sq km basin. The 200 member exploration team plans to complete a seismic survey covering 3,500 line km in the Kashi and Yecheng areas during the next 4 1/2 years. The survey follows a feasibility study that began last October covering 30,000 sq km in the basin.

  5. Northwest Ohio Final Report

    SciTech Connect

    Moyer, Kevin

    2015-03-04

    Improvement Districts or ESIDs and what is nationally known as Property Assessed Clean Energy or PACE districts and PACE financing. The project methodology followed the identify, develop, implement, monitor and measure format. These districts began in Toledo and adjoining areas and are expanding to TLCPA’s 28 county financing agency geographic footprint. What began as the Toledo Ohio Advanced Energy Improvement Corporation is now doing business as the Northwest Ohio Advanced Energy Improvement District recognizing it expansion into creating and financing other districts in NW Ohio. The program has been sought out as an advisor by major communities and states in the process of developing similar legislation and programs and has become one of the largest most successful PACE energy improvement and financing districts in the US. The program and the energy district focused on transforming energy use, delivery, conservation and renewable energy as “options of first choice”. The significant energy savings paid for many of the improvements and created a financially viable program well beyond the grant period. The program has become a model within the State of Ohio and Nationally on how to implement and finance projects in broad energy districts including how to evolve and integrate several financing methodologies. It is a unique utilization of revolving loan funds and energy bond pooling with revenue backing primarily from energy improvement special assessments on commercial properties along with some power purchase agreement (PPA) and loan agreement revenue. The program has also incorporated Qualified Energy Conservation Bonds, State of Ohio Energy Loans (SEP), utility rebates, solar and renewable energy certificates, renewable tax incentives and grants, and owner funded equity as additional program leverage and funding. Other keys to this success have been a continual simplification and refinement of the application and documentation process to make funding available easily

  6. Northwest Outward Bound Instructor's Manual.

    ERIC Educational Resources Information Center

    Northwest Outward Bound School, Portland, OR.

    Instructor responsibilities, procedures for completing activities safely, and instructional methods and techniques are outlined to assist instructors in the Northwest Outward Bound School (Portland, Oregon) as they strive for teaching excellence. Information is organized into six chapters addressing: history and philosophy of Outward Bound; course…

  7. Lessons on the Northwest Ordinance.

    ERIC Educational Resources Information Center

    Patrick, John J.

    The purpose of this packet of six lessons is to make it easier for teachers to include substantial instruction about the Northwest Ordinance in their secondary school courses. Each lesson includes a lesson plan for teachers and a lesson for students to study. The lessons are concise and can be completed in one or two class meetings. Each lesson…

  8. Radioactive air emissions notice of construction for the 105N Basin Stabilization

    SciTech Connect

    Coenenberg, E.T.

    1994-05-01

    The 105N Basin (basin) Stabilization will place the basin in a radiologically and environmentally safe condition so that it can be decommissioned at a later date. The basin is in the 105N Building, which is located in the 100N Area. The 100N Area is located in the Northern portion of the Hanford Site approximately 35 miles northwest of the city of Richland, Washington. The basin stabilization objectives are to inspect for Special Nuclear Material (SNM) (i.e., fuel assemblies and fuel pieces), remove the water from the basin and associated pits, and stabilize the basin surface. The stabilization will involve removal of basin hardware, removal of basin sediments, draining of basin water, and cleaning and stabilizing basin surfaces to prevent resuspension of radioactive emissions to the air. These activities will be conducted in accordance with all applicable regulations.

  9. 75 FR 23823 - Sixth Northwest Electric Power and Conservation Plan

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-04

    ... From the Federal Register Online via the Government Publishing Office PACIFIC NORTHWEST ELECTRIC POWER AND CONSERVATION PLANNING COUNCIL Sixth Northwest Electric Power and Conservation Plan AGENCY: Pacific Northwest Electric Power and Conservation Planning Council (Northwest Power and...

  10. Mineral resources prospecting by synthetic application of TM/ETM+, Quickbird and Hyperion data in the Hatu area, West Junggar, Xinjiang, China

    PubMed Central

    Liu, Lei; Zhou, Jun; Jiang, Dong; Zhuang, Dafang; Mansaray, Lamin R.; Hu, Zhijun; Ji, Zhengbao

    2016-01-01

    The Hatu area, West Junggar, Xinjiang, China, is situated at a potential gold-copper mineralization zone in association with quartz veins and small granitic intrusions. In order to identify the alteration zones and mineralization occurrences in this area, the Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+), Quickbird, Hyperion data and laboratory measured spectra were combined in identifying structures, alteration zones, quartz veins and small intrusions. The hue-saturation-intensity (HSI) color model transformation was applied to transform principal component analysis (PCA) combinations from R (Red), G (Green) and B (Blue) to HSI space to enhance faults. To wipe out the interference of the noise, a method, integrating Crosta technique and anomaly-overlaying selection, was proposed and implemented. Both Jet Propulsion Laboratory Spectral Library spectra and laboratory-measured spectra, combining with matched filtering method, were used to process Hyperion data. In addition, high-resolution Quickbird data were used for unraveling the quartz veins and small intrusions along the alteration zones. The Baobei fault and a SW-NE-oriented alteration zone were identified for the first time. This study eventually led to the discovery of four weak gold-copper mineralized locations through ground inspection and brought new geological knowledge of the region’s metallogeny. PMID:26911195

  11. Mineral resources prospecting by synthetic application of TM/ETM+, Quickbird and Hyperion data in the Hatu area, West Junggar, Xinjiang, China.

    PubMed

    Liu, Lei; Zhou, Jun; Jiang, Dong; Zhuang, Dafang; Mansaray, Lamin R; Hu, Zhijun; Ji, Zhengbao

    2016-01-01

    The Hatu area, West Junggar, Xinjiang, China, is situated at a potential gold-copper mineralization zone in association with quartz veins and small granitic intrusions. In order to identify the alteration zones and mineralization occurrences in this area, the Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+), Quickbird, Hyperion data and laboratory measured spectra were combined in identifying structures, alteration zones, quartz veins and small intrusions. The hue-saturation-intensity (HSI) color model transformation was applied to transform principal component analysis (PCA) combinations from R (Red), G (Green) and B (Blue) to HSI space to enhance faults. To wipe out the interference of the noise, a method, integrating Crosta technique and anomaly-overlaying selection, was proposed and implemented. Both Jet Propulsion Laboratory Spectral Library spectra and laboratory-measured spectra, combining with matched filtering method, were used to process Hyperion data. In addition, high-resolution Quickbird data were used for unraveling the quartz veins and small intrusions along the alteration zones. The Baobei fault and a SW-NE-oriented alteration zone were identified for the first time. This study eventually led to the discovery of four weak gold-copper mineralized locations through ground inspection and brought new geological knowledge of the region's metallogeny. PMID:26911195

  12. Mineral resources prospecting by synthetic application of TM/ETM+, Quickbird and Hyperion data in the Hatu area, West Junggar, Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Zhou, Jun; Jiang, Dong; Zhuang, Dafang; Mansaray, Lamin R.; Hu, Zhijun; Ji, Zhengbao

    2016-02-01

    The Hatu area, West Junggar, Xinjiang, China, is situated at a potential gold-copper mineralization zone in association with quartz veins and small granitic intrusions. In order to identify the alteration zones and mineralization occurrences in this area, the Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+), Quickbird, Hyperion data and laboratory measured spectra were combined in identifying structures, alteration zones, quartz veins and small intrusions. The hue-saturation-intensity (HSI) color model transformation was applied to transform principal component analysis (PCA) combinations from R (Red), G (Green) and B (Blue) to HSI space to enhance faults. To wipe out the interference of the noise, a method, integrating Crosta technique and anomaly-overlaying selection, was proposed and implemented. Both Jet Propulsion Laboratory Spectral Library spectra and laboratory-measured spectra, combining with matched filtering method, were used to process Hyperion data. In addition, high-resolution Quickbird data were used for unraveling the quartz veins and small intrusions along the alteration zones. The Baobei fault and a SW-NE-oriented alteration zone were identified for the first time. This study eventually led to the discovery of four weak gold-copper mineralized locations through ground inspection and brought new geological knowledge of the region’s metallogeny.

  13. Mineral resources prospecting by synthetic application of TM/ETM+, Quickbird and Hyperion data in the Hatu area, West Junggar, Xinjiang, China.

    PubMed

    Liu, Lei; Zhou, Jun; Jiang, Dong; Zhuang, Dafang; Mansaray, Lamin R; Hu, Zhijun; Ji, Zhengbao

    2016-01-01

    The Hatu area, West Junggar, Xinjiang, China, is situated at a potential gold-copper mineralization zone in association with quartz veins and small granitic intrusions. In order to identify the alteration zones and mineralization occurrences in this area, the Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+), Quickbird, Hyperion data and laboratory measured spectra were combined in identifying structures, alteration zones, quartz veins and small intrusions. The hue-saturation-intensity (HSI) color model transformation was applied to transform principal component analysis (PCA) combinations from R (Red), G (Green) and B (Blue) to HSI space to enhance faults. To wipe out the interference of the noise, a method, integrating Crosta technique and anomaly-overlaying selection, was proposed and implemented. Both Jet Propulsion Laboratory Spectral Library spectra and laboratory-measured spectra, combining with matched filtering method, were used to process Hyperion data. In addition, high-resolution Quickbird data were used for unraveling the quartz veins and small intrusions along the alteration zones. The Baobei fault and a SW-NE-oriented alteration zone were identified for the first time. This study eventually led to the discovery of four weak gold-copper mineralized locations through ground inspection and brought new geological knowledge of the region's metallogeny.

  14. Seismic stratigraphy or Cape Sorell Basin, Tasmania

    SciTech Connect

    Bellow, T.L.

    1990-05-01

    Because large new exploration areas have become scarce, the Cape Sorell basin has become an increasingly attractive frontier area. Cape Sorell basin, located along the western passive continental margin of Tasmania formed as a result of the breakup of eastern Gondwanaland 95{plus minus}5 Ma. An extensional fault system trending west-northwest with dip-slip movement down to the south-southwest forms the northern boundary and a second fault system trending north-northwest with oblique slip down to the south-southwest creates the basin. Second order extensional faults within the basin have created wrench-type flower structures, which are potential migration pathways for hydrocarbons. Nine distinct depositional sequences identified within the Cape Sorell basin record the evolution of this passive continental margin. Late Cretaceous-early Paleocene sequences were deposited as the rifting ceased and clastic progradation over the rift terrain began. Relative lowering of sea level occurred during the Paleocene, resulting in extensive channeling of the Late Cretaceous-early Paleocene sequences. A subsequent rise in relative sea level resulted in canyon-fill deposition during the early Paleocene to early Eocene. During the Eocene, sedimentation sufficiently increased to produce a downlapping sediment progradation characterized by deltaic depositional environment. Although interrupted several times by changes in relative sea level and shifting sediment sources, deltaic deposition continued until the late Oligocene. As the rate of clastic sedimentation slowed, carbonate shelf deposition began and has typified the basin since late the Oligocene.

  15. Gravity Analysis of the Jeffera Basin, Tunisia

    NASA Astrophysics Data System (ADS)

    Mickus, K.; Gabtni, H.; Jallouli, C.

    2004-12-01

    Southern Tunisia consists of two main tectonic provinces: 1) the Saharan Platform and 2) the folded Atlasic domain, separated by the North Saharan Flexure. The Saharan Platform, which contains the Ghadames Basin and the Telemzane Arch, consists of gently dipping Paleozoic strata overlain by Triassic to Cretaceous sediments. The Atlasic domain consists of a thicker sequence of mainly Mesozoic and younger rock with less complete sequences of Paleozoic strata. Within the Atlasic domain are the still actively subsiding Chotts and Jeffera basins. The Jeffera basin, which occurs to the east of the Telemzane Arch contains at least eight kilometers of Paleozoic and younger sediment that were formed during numerous subsidence episodes since Carboniferous time. The Jeffera basin is dominated by tilted fault blocks that were formed during numerous tectonic episodes. Several unpublished seismic reflection profiles and well data exist for the Jeffera basin, however a deep structural analysis of the basin has not been published. We examined the existing gravity data in conjunction with available well and geologic data to determine structural features within the basin. The Bouguer gravity anomaly map shows that the Jeffera basin is dominated by a narrow northwest-trending gravity minimum. However, a more detailed analysis consisting of wavelength filtering and edge enhancements indicate that the structure of the basin is more complicated than indicated by the Bouguer gravity anomaly map. A residual gravity anomaly map indicates that the Jeffera basin consists of at least three and maybe four subbasins. Additionally, the Jeffera Fault marks the boundary between northwest-trending gravity anomalies to its northeast and east-trending anomalies over the Saharan Platform. The above observation is amplified by the construction of the enhanced horizontal derivatives (EHG) of both the complete Bouguer gravity and the residual gravity anomaly maps. The EHG maps highlight the lateral

  16. A classification of Meso-Cenozoic continental basins and their oil-gas potentials in China

    SciTech Connect

    Wu Changlin ); Xue Shuhao )

    1991-03-01

    Most of the oilfields in China are located in Mesozoic-Cenozoic continental basins. Characteristics of continental sediments are controlled by such factors as paleoclimatic zones, distance from oceans, paleogeomorphic features, and tectonic settings. Based on paleoclimatic zonation, the continental basins in China can be divided into humid, arid, and humid-arid transitional types. Furthermore, based on the distances from oceans, they can be classified into inland and onshore types, and based on regional geomorphic features, they can be classified into faulted and depressional types. According to three factors, the Mesozoic-Cenozoic continental petroliferous basins in China can be grouped under ten types as follows: (1) onshore humid faulted type such as Zhujiangkou (Pearl River Mouth; E); (2) onshore humid depressional type such as Songliao (K); (3) inland humid faulted type such as Baise (E); (4) inland humid depressional type such as Ordos (T); (5) onshore arid-humid faulted type such as Bohai Bay (E); (6) inland arid-humid faulted type such as Jiuxi (K); (7) inland arid-humid depressional type such as Junggar (E); (8) onshore arid depressional type such as Tarim (E); (9) inland arid faulted type such as Jianghan (E); and (10) inland arid depressional type such as Tsaidam (E-N). Sedimentary systems in different basins have different depositional characteristics and petroliferous potentials. Onshore basins in humid zone and arid-humid transitional zone have best petroleum prospects, and inland basins in humid and arid-humid transitional zones are second while the basins in arid zone are third.

  17. Structural and stratigraphic analysis of the paleozoic Murzuk and Ghadames basins, western Libya

    NASA Astrophysics Data System (ADS)

    Karasek, R. M.

    The intracratonic basins in western Libya are characterized by extensional basement controlled faulting along northwest and northeast trends. The northwest southeast trending Tripoli-Soda, Ben Ghenma and Hasi Atshan subsurface arches were uplifted from Cambian through Devonian time. The anomalous west-southwest trending Gargaf Arch acted as a hinge line from Silurian through Devonian time, with consequent paleoslopes to the northwest (Ghadames Basin) and southeast (Murzuk Basin). Paleozoic detrital sediments are up to 1500 m thick in the Murzuk Basin and 2500 m thick in the Ghadames Basin. Five depositional sequences comprise transgressive-regressive cycles of deposition from parallic (coarse grained) to marine (fine-grained). Detailed environmental interpretation of the sequences is based on outcrop models for the Middle Devonian-Lower Carboniferous Aouinet Ouenine and Shatti Formations.

  18. The Cambrian initiation of intra-oceanic subduction in the southern Paleo-Asian Ocean: Further evidence from the Barleik subduction-related metamorphic complex in the West Junggar region, NW China

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Han, Bao-Fu; Xu, Zhao; Ren, Rong; Zhang, Jin-Rui; Zhou, Jing; Su, Li; Li, Qiu-Li

    2016-06-01

    In this study, we present new evidence from the Barleik subduction-related metamorphic complex in the southern West Junggar region, northwestern China, for the Cambrian initiation of intra-oceanic subduction in the southern Paleo-Asian Ocean. The Barleik metamorphic complex is mainly composed of blueschist and amphibolite blocks within an ophiolitic mélange and their protoliths are calc-alkaline andesite and alkali and tholeiitic basalts. The calc-alkaline andesite has a zircon U-Pb age of 502 ± 2 Ma, obtained from magmatic cores of zircon grains, and shares geochemical features similar to the 515-485 Ma intra-oceanic arc magmatic rocks in the West Junggar region. By contrast, the alkali and tholeiitic basalts have trace element features similar to ocean island and enriched mid-ocean ridge basalts, respectively. Rutile and sodic-calcic amphibole from the amphibolite have a U-Pb age of 502 ± 25 Ma and a 40Ar/39Ar age of ∼504 Ma, respectively, which are in good agreement within errors with a 40Ar/39Ar age of 492 ± 4 Ma for phengite from the blueschist. These metamorphic ages of ∼500 Ma are interpreted to represent the timing of Pacific-type subduction-related metamorphism and are also compatible with ages of the oldest supra-subduction zone ophiolites (531-512 Ma) and intra-oceanic arc plutons (515-485 Ma) in the southern West Junggar region. Being one of the oldest subduction-related metamorphic complexes (509-490 Ma) in the southern Central Asian Orogenic Belt, the Barleik metamorphic complex, together with the oldest arc plutons, definitely indicate the initial intra-oceanic subduction in the southern Paleo-Asian Ocean at least in the Early Cambrian.

  19. New interpretation of Clarks Fork field, northern Bighorn basin, Montana

    SciTech Connect

    Johnson, J.S.; Lindsley-Griffin, N.

    1986-08-01

    Clarks Fork field is located at the northern edge of the Bighorn basin (T9S, R22E) in Carbon County, Montana. Production was first established in 1944 by General Petroleum Corporation in the Cretaceous Peay Sandstone (basal Frontier) and was later extended to the Cretaceous Greybull (1949) and Lakota (1956) sandstones by British American. Total cumulative hydrocarbons from this field are 1,1789,193 bbl of oil and 3,061,522 mcf of gas, with Lakota sandstones being most productive. Lakota production occurs from a structural-stratigraphic trap in an east-west-trending channel on the axis of Clarks Fork anticline, geographically near the center of the township. Our structural reinterpretation of Clarks Fork field suggests that Elk Basin anticline is a northwest extension of the Elk Basin field anticline. The Elk Basin thrust truncates the north limb of the fold and does not strike to the northwest, as shown by earlier interpretations. They interpret a northwest-striking thrust in the center of the township as a splay off the Elk Basin thrust, and have named it the Clarks Fork thrust. The Clarks Fork anticline is located on the hanging wall of Clarks Fork thrust. Subsurface maps indicate the Clarks Fork area has not been fully developed. Stratigraphic traps in the Lakota and Greybull sandstones are present in several areas of the township. Structural traps in the center and northwest portions of the township may also exist.

  20. National emission standards for hazardous air pollutants application for approval to stabilize the 105N Basin

    SciTech Connect

    Not Available

    1994-05-01

    The 105N Basin (basin) Stabilization will place the basin in a radiologically and environmentally safe condition so that it can be decommissioned at a later date. The basin stabilization objectives are to inspect for Special Nuclear Material (SNM) (i.e., fuel assemblies and fuel pieces), remove the water from the basin and associated pits, and stabilize the basin surface. The stabilization will involve removal of basin hardware, removal of basin sediments, draining of basin water, and cleaning and stabilizing basin surfaces-to prevent resuspension of radioactive emissions to the air. These activities will be conducted in accordance with all applicable regulations. The basin is in the 105N Building, which is located in the 100N Area. The 100N Area is located in the Northern portion of the Hanford Site approximately 35 miles northwest of the city of Richland, Washington. The basin is a reinforced unlined concrete structure 150 feet long, 50 feet wide, and 24 feet deep. The basin is segregated into seven areas sharing a common pool of water; the Discharge/Viewing (``D``) Pit, the fuel segregation pit (including a water tunnel that connects the ``D`` pit and segregation pit), two storage basins designated as North Basin and South Basin, two cask load-out pits, and a fuel examination area. The North Basin floor is entirely covered and the South Basin is partly covered by a modular array of cubicles formed by boron concrete posts and boron concrete panels.

  1. Columbia Basin Fish and Wildlife Authority Project Abstracts; May 25-27, Portland, Oregon, 1997 Annual Review.

    SciTech Connect

    Allee, Brian J.

    1997-06-26

    Abstracts are presented from the 1997 Columbia Basin Fish and Wildlife Program Review of Projects. The purpose was to provide information and education on the approximate 127 million dollars in Northwest electric ratepayer fish and wildlife mitigation projects funded annually.

  2. Petroleum systems of the Northwest Java Province, Java and offshore southeast Sumatra, Indonesia

    USGS Publications Warehouse

    Bishop, Michele G.

    2000-01-01

    Mature, synrift lacustrine shales of Eocene to Oligocene age and mature, late-rift coals and coaly shales of Oligocene to Miocene age are source rocks for oil and gas in two important petroleum systems of the onshore and offshore areas of the Northwest Java Basin. Biogenic gas and carbonate-sourced gas have also been identified. These hydrocarbons are trapped primarily in anticlines and fault blocks involving sandstone and carbonate reservoirs. These source rocks and reservoir rocks were deposited in a complex of Tertiary rift basins formed from single or multiple half-grabens on the south edge of the Sunda Shelf plate. The overall transgressive succession was punctuated by clastic input from the exposed Sunda Shelf and marine transgressions from the south. The Northwest Java province may contain more than 2 billion barrels of oil equivalent in addition to the 10 billion barrels of oil equivalent already identified.

  3. Pacific Northwest Resources Inventory Demonstration

    NASA Technical Reports Server (NTRS)

    Nichols, J. D.

    1976-01-01

    The Pacific Northwest Land Resource Inventory Demonstration project is designed to demonstrate to users from state and local agencies in Washington, Oregon, and Idaho the cost effective role that Landsat derived information can play in natural resource planning and management when properly supported by ground and aircraft data. The project has been organized into five main phases: (1) maps and overlays, (2) early digital image analysis, (3) demonstration of applications using interactive image analysis, (4) Landsat products and land resources information systems, and (5) documentation. The demonstration project has been applied to Washington forestry, water inventory in southern Idaho, and monitoring of tansy ragwort in western Oregon.

  4. Invasive crayfish in the Pacific Northwest

    USGS Publications Warehouse

    Pearl, Christopher A.; McCreary, Brome; Adams, Michael

    2011-01-01

    Invasive species directly threaten freshwater biodiversity, particularly in regions of high aquatic richness like the Pacific Northwest (PNW). Crayfish are among the most impactful of aquatic invasive species. Invasive crayfish are considered ecosystem engineers due to their ability to alter basic wetland properties, such as reducing vegetation and bank integrity and increasing turbidity. In areas where invasion is advanced, crayfish pose major economic and ecological problems. Crayfish have been widely introduced for aquaculture and can become established in a wide range of habitat conditions. They also may be spread by anglers who use them as bait. Several non-native crayfish are established in the PNW, but the extent of their invasion is not well known. At least two groups are known from scattered sites in the PNW, and both have proven problematic for native species in other parts of the world: Red swamp crayfish (Procambarus clarkii) and several members of the genus Orconectes. Both groups are native to areas of the eastern United States. Both are identified globally as invasives of high concern and appear on the Oregon Department of Fish and Wildlife's "10 Most Unwanted" and the U.S. Forest Service's "Primary Species of Concern" lists for stream systems in the PNW. Despite the presence of introduced crayfish in the PNW and their high potential for negative effects, the scope of their invasion and effects on aquatic systems are not well known. The U.S. Geological Survey (USGS), along with local groups and state agencies, is working to clarify crayfish distribution and to outline which basins may not yet be invaded. Other goals are to improve understanding of habitat associations of invasive crayfish and their potential effects on native crayfish.

  5. 8. View, fuel waste tanks and containment basin associated with ...

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

    8. View, fuel waste tanks and containment basin associated with Components Test Laboratory (T-27) located uphill to the left, looking northwest. - Air Force Plant PJKS, Systems Integration Laboratory, Components Test Laboratory, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  6. Managing the Columbia Basin for Sustainable Economy, Society, Environment

    EPA Science Inventory

    The Columbia River Basin (CRB) is a vast region of the Pacific Northwest covering parts of the United States, Canada and Tribal lands. As the Columbia River winds its way from Canada into the US, the river passes through numerous multi-purpose reservoirs and hydroelectric genera...

  7. Progress and prospects of climate change impacts on hydrology in the arid region of northwest China.

    PubMed

    Chen, Yaning; Li, Zhi; Fan, Yuting; Wang, Huaijun; Deng, Haijun

    2015-05-01

    The arid region of Northwest China, located in the central Asia, responds sensitively to global climate change. Based on the newest research results, this paper analyzes the impacts of climate change on hydrology and the water cycle in the arid region of Northwest China. The analysis results show that: (1) In the northwest arid region, temperature and precipitation experienced "sharply" increasing in the past 50 years. The precipitation trend changed in 1987, and since then has been in a state of high volatility, during the 21st century, the increasing rate of precipitation was diminished. Temperature experienced a "sharply" increase in 1997; however, this sharp increasing trend has turned to an apparent hiatus since the 21st century. The dramatic rise in winter temperatures in the northwest arid region is an important reason for the rise in the average annual temperature, and substantial increases in extreme winter minimum temperature play an important role in the rising average winter temperature; (2) There was a significant turning point in the change of pan evaporation in the northwest arid area in 1993, i.e., in which a significant decline reversed to a significant upward trend. In the 21st century, the negative effects of global warming and increasing levels of evaporation on the ecology of the northwest arid region have been highlighted; (3) Glacier change has a significant impact on hydrology in the northwest arid area, and glacier inflection points have appeared in some rivers. The melting water supply of the Tarim River Basin possesses a large portion of water supplies (about 50%). In the future, the amount of surface water will probably remain at a high state of fluctuation. PMID:25682220

  8. Progress and prospects of climate change impacts on hydrology in the arid region of northwest China.

    PubMed

    Chen, Yaning; Li, Zhi; Fan, Yuting; Wang, Huaijun; Deng, Haijun

    2015-05-01

    The arid region of Northwest China, located in the central Asia, responds sensitively to global climate change. Based on the newest research results, this paper analyzes the impacts of climate change on hydrology and the water cycle in the arid region of Northwest China. The analysis results show that: (1) In the northwest arid region, temperature and precipitation experienced "sharply" increasing in the past 50 years. The precipitation trend changed in 1987, and since then has been in a state of high volatility, during the 21st century, the increasing rate of precipitation was diminished. Temperature experienced a "sharply" increase in 1997; however, this sharp increasing trend has turned to an apparent hiatus since the 21st century. The dramatic rise in winter temperatures in the northwest arid region is an important reason for the rise in the average annual temperature, and substantial increases in extreme winter minimum temperature play an important role in the rising average winter temperature; (2) There was a significant turning point in the change of pan evaporation in the northwest arid area in 1993, i.e., in which a significant decline reversed to a significant upward trend. In the 21st century, the negative effects of global warming and increasing levels of evaporation on the ecology of the northwest arid region have been highlighted; (3) Glacier change has a significant impact on hydrology in the northwest arid area, and glacier inflection points have appeared in some rivers. The melting water supply of the Tarim River Basin possesses a large portion of water supplies (about 50%). In the future, the amount of surface water will probably remain at a high state of fluctuation.

  9. The Northwest Ordinance. A Special Issue.

    ERIC Educational Resources Information Center

    Sheehan, Bernard W., Ed.; And Others

    1988-01-01

    Eight articles discuss different aspects of the Northwest ordinances. W. W. Abbot emphasizes George Washington's enduring, complex, and deep involvement with the west and its land. Robert V. Remini points out the value of the Articles of Confederation by emphasizing that it was the Congress under the Articles that passed the Northwest Ordinance.…

  10. 77 FR 40565 - Northwest Forest Plan Provincial Advisory Committees

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-10

    ... Forest Service Northwest Forest Plan Provincial Advisory Committees AGENCY: Forest Service, USDA. ACTION: Notice of Administrative Meetings for the Northwest Forest Plan Provincial Advisory Committees. SUMMARY... up under the Northwest Forest Plan. The PIECs facilitate the successful implementation of the...

  11. 2. INTAKE CHANNEL LOOKING NORTHWEST; GATES 1, 2, AND 3 ...

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

    2. INTAKE CHANNEL LOOKING NORTHWEST; GATES 1, 2, AND 3 SHOWING. - Hondius Water Line, 1.6 miles Northwest of Park headquarters building & 1 mile Northwest of Beaver Meadows entrance station, Estes Park, Larimer County, CO

  12. Pacific Northwest Laboratory CALIOPE overview

    SciTech Connect

    McDowell, R.S.; Kelly, J.F.; Sharpe, S.W.

    1995-03-01

    This overview covers progress in the following areas in which Pacific Northwest Laboratory contributes to the CALIOPE Program: (1) Fabrication of electro-optic modulators to generate FM-coding on IR lasers in the 8-12 and 3-5 {mu}m regions. (2) IR spectroscopy of signature species, abnormal isotopic distributions, hydrolysis and kinetics of effluents interacting with the atmosphere, and reflectance measurements of natural surfaces. (3) Systems analysis of FM-DIAL concepts, including lateral phase coherence and MTF measurements, and laboratory tests of detector technology and demodulation methods. (4) Field tests of FM-DIAL, covering field validation of portable diode laser concepts, FM-CO{sub 2} interrogation of Hanford sites, and signal returns from natural specular surfaces. (5) Ancillary matters: ground-truthing at Hanford (and RSTR?), countermeasures, and new laser design concepts.

  13. An index of biological integrity (IBI) for Pacific Northwest rivers

    USGS Publications Warehouse

    Mebane, C.A.; Maret, T.R.; Hughes, R.M.

    2003-01-01

    The index of biotic integrity (IBI) is a commonly used measure of relative aquatic ecosystem condition; however, its application to coldwater rivers over large geographic areas has been limited. A seven-step process was used to construct and test an IBI applicable to fish assemblages in coldwater rivers throughout the U.S. portion of the Pacific Northwest. First, fish data from the region were compiled from previous studies and candidate metrics were selected. Second, reference conditions were estimated from historical reports and minimally disturbed reference sites in the region. Third, data from the upper Snake River basin were used to test metrics and develop the initial index. Fourth, candidate metrics were evaluated for their redundancy, variability, precision, and ability to reflect a wide range of conditions while distinguishing reference sites from disturbed sites. Fifth, the selected metrics were standardized by being scored continuously from 0 to 1 and then weighted as necessary to produce an IBI ranging from 0 to 100. The resulting index included 10 metrics: number of native coldwater species, number of age-classes of sculpins Cottus spp., percentage of sensitive native individuals, percentage of coldwater individuals, percentage of tolerant individuals, number of alien species, percentage of common carp Cyprinus carpio individuals, number of selected salmonid age-classes, catch per unit effort of coldwater individuals, and percentage of individuals with selected anomalies. Sixth, the IBI responses were tested with additional data sets from throughout the Pacific Northwest. Last, scores from two minimally disturbed reference rivers were evaluated for longitudinal gradients along the river continuum. The IBI responded to environmental disturbances and was spatially and temporally stable at over 150 sites in the Pacific Northwest. The results support its use across a large geographic area to describe the relative biological condition of coolwater and

  14. Identifying block structure in the Pacific Northwest, USA

    USGS Publications Warehouse

    Savage, James C.; Wells, Ray E.

    2015-01-01

    We have identified block structure in the Pacific Northwest (west of 116°W between 38°N and 49°N) by clustering GPS stations so that the same Euler vector approximates the velocity of each station in a cluster. Given the total number k of clusters desired, the clustering procedure finds the best assignment of stations to clusters. Clustering is calculated for k= 2 to 14. In geographic space, cluster boundaries that remain relatively stable as k is increased are tentatively identified as block boundaries. That identification is reinforced if the cluster boundary coincides with a geologic feature. Boundaries identified in northern California and Nevada are the Central Nevada Seismic Belt, the west side of the Northern Walker Lane Belt, and the Bartlett Springs Fault. Three blocks cover all of Oregon and Washington. The principal block boundary there extends west-northwest along the Brothers Fault Zone, then north and northwest along the eastern boundary of Siletzia, the accreted oceanic basement of the forearc. East of this boundary is the Intermountain block, its eastern boundary undefined. A cluster boundary at Cape Blanco subdivides the forearc along the faulted southern margin of Siletzia. South of Cape Blanco the Klamath Mountains-Basin and Range block extends east to the Central Nevada Seismic Belt and south to the Sierra Nevada-Great Valley block. The Siletzia block north of Cape Blanco coincides almost exactly with the accreted Siletz terrane. The cluster boundary in the eastern Olympic Peninsula may mark permanent shortening of Siletzia against the Intermountain block.

  15. Identifying block structure in the Pacific Northwest, USA

    NASA Astrophysics Data System (ADS)

    Savage, J. C.; Wells, R. E.

    2015-11-01

    We have identified block structure in the Pacific Northwest (west of 116°W between 38°N and 49°N) by clustering GPS stations so that the same Euler vector approximates the velocity of each station in a cluster. Given the total number k of clusters desired, the clustering procedure finds the best assignment of stations to clusters. Clustering is calculated for k = 2-14. In geographic space, cluster boundaries that remain relatively stable as k is increased are tentatively identified as block boundaries. That identification is reinforced if the cluster boundary coincides with a geologic feature. Boundaries identified in Northern California and Nevada are the Central Nevada Seismic Belt, the west side of the Northern Walker Lane Belt, and the Bartlett Springs Fault. Three blocks cover all of Oregon and Washington. The principal block boundary there extends west-northwest along the Brothers Fault Zone, then north and northwest along the eastern boundary of Siletzia, the accreted oceanic basement of the forearc. East of this boundary is the Intermountain block; its eastern boundary undefined. A cluster boundary at Cape Blanco subdivides the forearc along the faulted southern margin of Siletzia. South of Cape Blanco, the Klamath Mountains-Basin and Range block, extends east to the Central Nevada Seismic Belt and south to the Sierra Nevada-Great Valley block. The Siletzia block, north of Cape Blanco, coincides almost exactly with the accreted Siletz terrane. The cluster boundary in the eastern Olympic Peninsula may mark permanent shortening of Siletzia against the Intermountain block.

  16. Seismic Characterization of the Jakarta Basin

    NASA Astrophysics Data System (ADS)

    Cipta, A.; Saygin, E.; Cummins, P. R.; Masturyono, M.; Rudyanto, A.; Irsyam, M.

    2015-12-01

    Jakarta, Indonesia, is home to more than 10 million people. Many of these people live in seismically non-resilient structures in an area that historical records suggest is prone to earthquake shaking. The city lies in a sedimentary basin composed of Quaternary alluvium that experiences rapid subsidence (26 cm/year) due to groundwater extraction. Forecasts of how much subsidence may occur in the future are dependent on the thickness of the basin. However, basin geometry and sediment thickness are poorly known. In term of seismic hazard, thick loose sediment can lead to high amplification of seismic waves, of the kind that led to widespread damage in Mexico city during the Michoacan Earthquake of 1985. In order to characterize basin structure, a temporary seismograph deployment was undertaken in Jakarta in Oct 2013- Jan 2014. A total of 96 seismic instrument were deployed throughout Jakarta were deployed throughout Jakarta at 3-5 km spacing. Ambient noise tomography was applied to obtain models of the subsurface velocity structure. Important key, low velocity anomalies at short period (<8s) correspond to the main sedimentary sub-basins thought to be present based on geological interpretations of shallow stratigraphy in the Jakarta Basin. The result shows that at a depth of 300 m, shear-wave velocity in the northern part (600 m/s) of the basin is lower than that in the southern part. The most prominent low velocity structure appears in the northwest of the basin, down to a depth of 800 m, with velocity as low as 1200 m/s. This very low velocity indicates the thickness of sediment and the variability of basin geometry. Waveform computation using SPECFEM2D shows that amplification due to basin geometry occurs at the basin edge and the thick sediment leads to amplification at the basin center. Computation also shows the longer shaking duration occurrs at the basin edge and center of the basin. The nest step will be validating the basin model using earthquake events

  17. LODGEPOLE BRIDGE, FACING NORTHWEST Generals Highway, Lodge Pole Bridge, ...

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

    LODGEPOLE BRIDGE, FACING NORTHWEST - Generals Highway, Lodge Pole Bridge, Spanning Marble Fork of Kaweah River, approximately 21 miles northwest of Ash Mountain Entrance, Three Rivers, Tulare County, CA

  18. Zircon U-Pb geochronology, geochemistry, and Sr-Nd-Hf isotopes of granitoids in the Yulekenhalasu copper ore district, northern Junggar, China: Petrogenesis and tectonic implications

    NASA Astrophysics Data System (ADS)

    Yang, Fuquan; Chai, Fengmei; Zhang, Zhixin; Geng, Xinxia; Li, Qiang

    2014-03-01

    The Yulekenhalasu porphyry copper deposit is located in the Kalaxiange'er metallogenic belt in northern Junggar, China. We present the results from zircon U-Pb geochronology, and geochemical and Sr-Nd-Hf isotope analyses of the granitoids associated with the ore deposits with a view to constrain their petrogenesis and tectonic setting. The granitoids consist of quartz diorite, diorite porphyry, porphyritic monzonite, and quartz porphyry, emplaced at 382, 379, 375-374, and 348 Ma, respectively, which span Late Devonian to early Carboniferous ages. The ore-bearing intrusion is mainly diorite porphyry, with subordinate porphyritic monzonite. The Late Devonian intrusions are characterized by SiO2 contents of 54.5-64.79 wt.%, Na2O contents of 3.82-8.24 wt.%, enrichment in Na, light rare-earth elements (LREEs), and large ion lithophile elements. They also display relative depletion in Y, Ba, P, Nb, Ta, and Ti, and weak negative Eu anomalies (δEu = 0.6-0.87). The early Carboniferous quartz porphyry is characterized by high SiO2 content (72.26-73.35 wt.%), enrichment in LREEs, K, and Sr, and relative depletion in Y (10.82-12.52 ppm) and Yb (1.06-1.15 ppm). The Late Devonian and early Carboniferous granitoids are characterized by positive ɛNd(t) values (5.2-10.1, one sample at - 1.9), positive ɛHf(t) values (7.46-18.45), low (87Sr/86Sr)i values (0.70363-0.70476), and young crustal residence ages. These data indicate that the sources of the granitoids were mainly mantle-derived juvenile rocks. Geochemical and Nd-Sr-Hf isotopic data demonstrate that the Late Devonian granitoids formed in an oceanic island arc, and they were formed from different sources, among which the mineralized diorite porphyry might have originated from a mixed slab-derived and mantle wedge melt source. The early Carboniferous quartz porphyry was likely emplaced in a mature island arc environment, and was probably derived from juvenile crust.

  19. Fluvial Drainage Basins and Valley Networks: Eastern Margaritifer Sinus, Mars

    NASA Technical Reports Server (NTRS)

    Boothroyd, J. C.; Grant, J. A.

    1985-01-01

    The fluvial drainage of the eastern Margaritifer Sinus (MC-19NE, SE) and northeastern Argyre (MC-26NE) Quadrangles is dominated by two major longitudinal valley networks, the Parana/Loire system on the east, and the Samara Himera system to the west. It is believed that both of these drainages are through-going to the northwest and debouch into Margaritifer Chaos (general location: 12S, 22.5W). The Parana/Loire drainage is bounded on the east in part by an ancient multi-ringed impact basin. The Parana multi-digitate network drains northwest into a depositional basin, and impact basin floor, characterized by positive relief chaos. It is believed that Loire Vallis heads in the basin; thus Parana and Loire Valles may be treated as one system. Samara Valles heads in the northeastern Argyre Quadrangle and extends as a major truck valley to the northwest. Samara Valles cuts through the hills forming one of the concentric rings of the Ladon impact basin and joins the Himera drainage to trend in a more northerly direction to Margaritifer Chaos. The downstream portion of Himera is considered to be part of the Samara

  20. 1997 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    1997-12-01

    The 1997 White Book is presented in two documents: (1) this summary of Federal system and Pacific Northwest region loads and resources; and (2) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. Data detailing Pacific Northwest non-utility generating (NUG) resources is also available upon request. This analysis updates the 1996 pacific Northwest Loads and Resources Study, published in December 1996. In this loads and resources study, resource availability is compared with a medium forecast of electricity consumption. This document analyzes the Pacific Northwest`s projected loads and available generating resources in two parts: (1) the loads and resources of the Federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional power system which includes loads and resources in addition to the Federal system. This study presents the Federal system and regional analyses for the medium load forecast. This analysis projects the yearly average energy consumption and resource availability for Operating Years (OY) 1998--99 through 2007--08.

  1. Tectonic development of Michigan basin

    SciTech Connect

    Prouty, C.E.

    1986-08-01

    The general form of the Michigan basin and surrounding frame structures - the Findlay, Kankakee, and Wisconsin arches - was inherited from the Precambrian. An ongoing study has provided new information on present basin configuration and the evolution of intrabasinal structures during the Paleozoic. This study involves: (1) isopach, structure contour, depocenter, and lithofacies map preparation; (2) diagenetic and epigenetic dolomitization processes and patterns; (3) Landsat imagery and lineament interpretation; (4) recognition of shearing mechanics and the resulting shear faulting and folding; and (5) the recognition of radial faults in contrast to shear faults. Monitoring of the above throughout the Paleozoic indicates that tectonic events within the basin were episodic in nature. Stresses are recognized as external and, through Fourier analysis of lineaments (shear faults), may be demonstrated as from the southeast, probably the Appalachian mobile belt. Shear faults are seated in Precambrian rocks, although they are probably not of that age. The faults occur with accompanying shear folds in rocks possibly as early as the Late Ordovician or Middle Silurian, but definitely by the Middle Devonian with the principal faulting and folding during the post-Osage Mississippian. Local shifting of the depocenter within the general Saginaw Bay area occurred during the early Paleozoic with a major shift westward to the present central basin position accompanied by the development of the present north-northwest ellipticity of the basin during the post-Osage, pre-Meramecian Mississippian. Barrier separation of the West Michigan Lagoon occurred in the Middle Ordovician and Middle and Late Devonian. Radial structures can be demonstrated in at least the Upper Silurian and Upper Devonian.

  2. 1993 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    1993-12-01

    The Loads and Resources Study is presented in three documents: (1) this summary of Federal system and Pacific Northwest region loads and resources; (2) a technical appendix detailing forecasted Pacific Northwest economic trends and loads, and (3) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. In this loads and resources study, resource availability is compared with a range of forecasted electricity consumption. The forecasted future electricity demands -- firm loads -- are subtracted from the projected capability of existing and {open_quotes}contracted for{close_quotes} resources to determine whether Bonneville Power Administration (BPA) and the region will be surplus or deficit. If resources are greater than loads in any particular year or month, there is a surplus of energy and/or capacity, which BPA can sell to increase revenues. Conversely, if firm loads exceed available resources, there is a deficit of energy and/or capacity, and additional conservation, contract purchases, or generating resources will be needed to meet load growth. The Pacific Northwest Loads and Resources Study analyzes the Pacific Northwest`s projected loads and available generating resources in two parts: (1) the loads and resources of the Federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional power system, which includes loads and resource in addition to the Federal system. The loads and resources analysis in this study simulates the operation of the power system under the Pacific Northwest Coordination Agreement (PNCA) produced by the Pacific Northwest Coordinating Group. This study presents the Federal system and regional analyses for five load forecasts: high, medium-high, medium, medium-low, and low. This analysis projects the yearly average energy consumption and resource availability for Operating Years (OY) 1994--95 through 2003--04.

  3. Evidence for Right-lateral Shear Along the Northwest Margin of the Eastern Snake River Plain, Idaho

    NASA Astrophysics Data System (ADS)

    Payne, S. J.; McCaffrey, R.; King, R. W.

    2007-12-01

    Previous investigators have proposed that extension within the eastern Snake River Plain (ESRP) is accommodated by intrusion of dikes at a rate similar to the rate of extension in the surrounding Basin and Range. This hypothesis is primarily based on the lack of strike-slip offset along the northwest physiographic boundary of the ESRP, the lack of seismicity within the ESRP relative to the surrounding active Basin and Range, and the presence of NW-trending volcanic rift zones within the ESRP. The ESRP is a 400-km long region within the track of the Yellowstone Hotspot that extends from southern Idaho northeast into northwestern Wyoming. GPS data compiled for this study are used to test this hypothesis. Several institutions including the Idaho National Laboratory, National Geodetic Survey, Rensselaer Polytechnic Institute, and University of Utah observed GPS stations from 1994 to 2007 within the ESRP and surrounding region. The GPS velocities show the average orientation of horizontal GPS velocities in the adjacent northwest Basin and Range region is similar to the average orientation for the ESRP (N113°W vs N91°W, respectively), but the average magnitude of horizontal GPS velocities in the Basin and Range (1.4 ± 0.3 mm/yr) is less than that for the ESRP (2.2 ± 0.3 mm/yr). Additionally, the adjacent northwest Basin and Range extends at about 9 x 10-9 /yr with most of the deformation localized along three NW-trending normal faults (Lost River, Lemhi, and Beaverhead). In contrast, the ESRP extends at a rate that is an order of magnitude lower than the adjacent northwest Basin and Range and we see little indication of extension along the Great Rift or other volcanic rift zones over the 400 km length. The GPS differential motion along the region of the ESRP adjacent to the northwest Basin and Range indicates a NE-trending zone of right-lateral shear. Preliminary inversions of GPS velocities, earthquakes, faults, and volcanic features indicate this zone of right

  4. Aleutian basin oceanic crust

    USGS Publications Warehouse

    Christeson, Gail L.; Barth, Ginger A.

    2015-01-01

    We present two-dimensional P-wave velocity structure along two wide-angle ocean bottom seismometer profiles from the Aleutian basin in the Bering Sea. The basement here is commonly considered to be trapped oceanic crust, yet there is a change in orientation of magnetic lineations and gravity features within the basin that might reflect later processes. Line 1 extends ∼225 km from southwest to northeast, while Line 2 extends ∼225 km from northwest to southeast and crosses the observed change in magnetic lineation orientation. Velocities of the sediment layer increase from 2.0 km/s at the seafloor to 3.0–3.4 km/s just above basement, crustal velocities increase from 5.1–5.6 km/s at the top of basement to 7.0–7.1 km/s at the base of the crust, and upper mantle velocities are 8.1–8.2 km/s. Average sediment thickness is 3.8–3.9 km for both profiles. Crustal thickness varies from 6.2 to 9.6 km, with average thickness of 7.2 km on Line 1 and 8.8 km on Line 2. There is no clear change in crustal structure associated with a change in orientation of magnetic lineations and gravity features. The velocity structure is consistent with that of normal or thickened oceanic crust. The observed increase in crustal thickness from west to east is interpreted as reflecting an increase in melt supply during crustal formation.

  5. Pleural calcification in northwest Greece

    SciTech Connect

    Bazas, T.; Oakes, D.; Gilson, J.C.; Bazas, B.; McDonald, J.C.

    1985-12-01

    Mass miniature radiography in 1969 detected a high prevalence of pleural calcification in three villages in northwest Greece. In 1980 a survey of a 15% sample of the population over the age of 10 was carried out with a 80% response rate. Full-size radiographs, ventilatory capacity measurements, and a detailed questionnaire on respiratory symptoms, type of work, and residence were used. Independent classification of the 408 films by two readers using the ILO/UC scheme showed very few small opacities but a very high prevalence of pleural calcification first evident in young adults and rising to 70% in the elderly. The overall prevalence was 34.7% in men and 21.5% in women. A comparison with the 1969 survey showed a progression rate of 5% per annum. In neither sex was there a significant relation of pleural calcification to smoking, ventilatory capacity, nor type of work, though those classified as field croppers had a slightly higher prevalence. There was no obvious evidence of increased lung cancer or mesothelioma in the village. The agent responsible for this apparently benign condition was not identified.

  6. Acid Precipitation in the Pacific Northwest.

    ERIC Educational Resources Information Center

    Baldwin, John; Kozak, David

    1988-01-01

    Discusses the causes, sources, and problems associated with acid deposition in the Pacific Northwest. Includes a learning activity about acid rain, "Deadly Skies," which was adapted from the Project WILD Aquatic Supplement. (TW)

  7. 1994 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    1994-12-01

    The 1994 Pacific Northwest Loads and Resources Study presented herein establishes a picture of how the agency is positioned today in its loads and resources balance. It is a snapshot of expected resource operation, contractual obligations, and rights. This study does not attempt to present or analyze future conservation or generation resource scenarios. What it does provide are base case assumptions from which scenarios encompassing a wide range of uncertainties about BPA`s future may be evaluated. The Loads and Resources Study is presented in two documents: (1) this summary of Federal system and Pacific Northwest region loads and resources and (2) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. This analysis updates the 1993 Pacific Northwest Loads and Resources Study, published in December 1993. In this loads and resources study, resource availability is compared with a range of forecasted electricity consumption. The Federal system and regional analyses for medium load forecast are presented.

  8. Tectonic evolution of northwest Siberia

    SciTech Connect

    Natapov, L.P. )

    1993-09-01

    The ancient Siberian continent was split from early Pangen in early Riphean. The newly formed continent drifted from the southern to the northern hemisphere, reaching high altitudes only in the Late Paleozoic. Up to the Early Carboniferous, a typical passive margin of the Atlantic type, prograding to the ocean, developed along the present northern and eastern boundaries of this continent. In Upper Paleozoic, Triassic, and Jurassic, the carbonate sedimentation was replaced by the accumulation of thick terrigenous complexes along the northern and southern margins. Large submarine plains were formed by the merging of fans, while eustatic lowering of the ocean level enlarged the source area of detrital material. Distal facies, with time, were moving into the ocean. Rifting, penetrating inside the continent, conditioned for formation of large sedimentary basins. The development of the Sukhanskaya syneclise is associated with Riphean rifting, and Vilyuiskaya with Upper Devonian rifting. In the Upper Mesozoic, the covergent boundaries of lithospheric plates existed along the northern and eastern boundaries of the Siberian continent. As a result of the final collision of the continental margin with blocks of different nature (microcontinents, island arcs, etc.) transported by the Kula plate, and with chukchi and north Taimyr arctic blocks, Verkhoyansk and Taimyr fold belts appeared in the Upper Cretaceous. They were over-thrusted on clastic wedges, putting into shape the present-day structure of foredeeps. In the paper, principal attention is devoted to peculiarities of structure and development of sedimentary basins, formation of oil-producing complexes, and structures favorable for accumulation of hydrocarbons. All these features are analyzed at the background of this plate tectonic scenario.

  9. The Northwest Indiana Robotic Telescope

    NASA Astrophysics Data System (ADS)

    Slavin, Shawn D.; Rengstorf, A. W.; Aros, J. C.; Segally, W. B.

    2011-01-01

    The Northwest Indiana Robotic (NIRo) Telescope is a remote, automated observing facility recently built by Purdue University Calumet (PUC) at a site in Lowell, IN, approximately 30 miles from the PUC campus. The recently dedicated observatory will be used for broadband and narrowband optical observations by PUC students and faculty, as well as pre-college students through the implementation of standards-based, middle-school modules developed by PUC astronomers and education faculty. The NIRo observatory and its web portal are the central technical elements of a project to improve astronomy education at Purdue Calumet and, more broadly, to improve science education in middle schools of the surrounding region. The NIRo Telescope is a 0.5-meter (20-inch) Ritchey-Chrétien design on a Paramount ME robotic mount, featuring a seven-position filter wheel (UBVRI, Hα, Clear), Peltier (thermoelectrically) cooled CCD camera with 3056 x 3056, square, 12 μm pixels, and off-axis guiding. It provides a coma-free imaging field of 0.5 degrees square, with a plate scale of 0.6 arcseconds per pixel. The observatory has a wireless internet connection, local weather station which publishes data to an internet weather site, and a suite of CCTV security cameras on an IP-based, networked video server. Control of power to every piece of instrumentation is maintained via internet-accessible power distribution units. The telescope can be controlled on-site, or off-site in an attended fashion via an internet connection, but will be used primarily in an unattended mode of automated observation, where queued observations will be scheduled daily from a database of requests. Completed observational data from queued operation will be stored on a campus-based server, which also runs the web portal and observation database. Partial support for this work was provided by the National Science Foundation's Course, Curriculum, and Laboratory Improvement (CCLI) program under Award No. 0736592.

  10. Evidence of Crustal Faulting and Deformation in the Muckleshoot Basin, Washington

    NASA Astrophysics Data System (ADS)

    Cox, J.; Wolf, L. W.

    2015-12-01

    The Muckleshoot basin of western Washington, sandwiched between the Seattle Uplift on the west and the Cascade Range on the east, is deforming under north-south shortening and clockwise rotation of the north Cascadia forearc. Accommodating the regional strain are crustal faults in the Puget Lowland that cluster around three azimuths: east-west, northwest-southeast, and north-northwest-south-southeast. Evidence for all three groups appears on the periphery of the Muckleshoot basin. In this study, we add gravity measurements to an existing database to better define the geometry of the Muckleshoot basin and its relation to previously mapped faults appearing on the basin margins. A northwest-trending gravity high bisects the basin into two sub-basins, a larger one to the south and a smaller one to the north. We suggest that the gravity high is associated with a deep basement structure and its orientation is consistent with northward-directed crustal shortening. Regional-residual separation methods and derivative maps show pronounced magnetic lineations that extend faults expressed along the basin margins to east-west trending faults that cross the Puget Sound. Three intersecting cross-sectional models produced for this study are consistent with the following hypotheses: (1) the northwest-trending White River and Green River faults mapped on the eastern basin margin appear as south-verging, steeply dipping reverse faults in the central basin; (2) the north-northwest trending Franklin fault, mapped previously as a strike-slip fault, projects into the basin and shows little vertical offset in the single profile it crosses, and (3) the northwest trajectory of both the White River and Green River faults appears to curve southward as the faults traverse the Muckleshoot basin, following east-west oriented gravity and magnetic anomalies that cross the Puget Sound. Results from the study suggest that the faults and folds in Muckleshoot basin are actively interacting with other

  11. Timing of Cenozoic Basin Formation in Northern Sundaland, Southeast Asia

    SciTech Connect

    Liew, K.K. )

    1994-07-01

    The present shorelines of northern Sundaland show preferential northwest-southeast elongation. This trend is parallel for subparallel to major faults and suture in this region. Continental wrench/shear basins developed on the western portion of this region and back-arc basins developed on the western portion of this region and back-arc basins in the rest of the region are also aligned to this trend. Different basin geometries and structural patterns among Cenozoic basins in northern Sundaland indicate different origins and/or timing of basin formation. Wrench faulting has played a significant role in the formation of these Cenozoic basins. The continued collision of the Indian subplate with the Eurasian plate during early Cenozoic has caused a redistribution of stress within this region. Zones of weakness have been reactivated or created with large lateral displacements by these changes, thus initiating the subsidence of these basins. The episodic initiation of Cenozoic basins may have begun as early as Jurassic and continued till Oligocene.

  12. Hydrocarbon habitat of the Tuz Golu basin, central Anatolia, Turkey

    SciTech Connect

    More, C.; Bird, P.R.; Clark-Lowes, D.D. )

    1988-08-01

    The Tuz Golu basin (TGB) of central Anatolia has been interpreted as a northwest-southeast-aligned terraced forearc basin that accumulated a Maastrichtian to Holocene, predominantly terrigenous, sedimentary succession. Evidence is presented from an integrated study incorporating all seismic, gravity, and well data for the following basin evolution. (1) Late Cretaceous sedimentation on the west of the Kirsehir block with a diverse assemblage of facies including terrestrial, possible sabkha, shallow marine carbonate and turbidite deposits; (2) eastward subduction of Neotethys beginning in the Maastrichtian and development of the Tuz Golu as a forearc basin; (3) deposition of a thick Paleocene to Eocene flysch succession; (4) late Eocene inversion of the thick flysch section along the central axis of the basin and development of flanking shallow basins; (5) late Eocene-Oligocene emergence with deposition of evaporites and red beds in a restricted basin, followed by suturing of continental blocks, uplift, and erosion; (6) dextral displacement along the Kochisar fault; (7) Oligocene-Miocene diapirism of Eocene salt along major faults in the western shallow basin; and (8) terrestrial and lacustrine sedimentation in the neotectonic TGB. Of the 22 wells drilled in the TGB, four contained oil or gas shows from formations of Paleocene to Miocene age. Potential shale source rocks occur in the Upper Cretaceous, Paleocene, and Eocene sections. Cretaceous rudist reefs and Paleocene/Eocene sandstones provide target reservoirs, while Eocene salt represents an ideal seal. Late Eocene deformation created the major trap-forming structures of the basin.

  13. Late Cenozoic structure and correlations to seismicity along the Olympic-Wallowa Lineament, northwest United States

    USGS Publications Warehouse

    Mann, G.M.; Meyer, C.E.

    1993-01-01

    Late Cenozoic fault geometry, structure, paleoseismicity, and patterns of recent seismicity at two seismic zones along the Olympic-Wallowa lineament (OWL) of western Idaho, northeast Oregon, and southeast Washington indicate limited right-oblique slip displacement along multiple northwest-striking faults that constitute the lineament. The southern end of the OWL originates in the Long Valley fault system and western Snake River Plain in western Idaho. The OWL in northeast Oregon consists of a wide zone of northwest-striking faults and is associated with several large, inferred, pull-apart basins. The OWL then emerges from the Blue Mountain uplift as a much narrower zone of faults in the Columbia Plateau known as the Wallula fault zone (WFZ). Stuctural relationships in the WFZ strongly suggest that it is a right-slip extensional duplex. -from Authors

  14. Definition of basin phases in the Petrel Sub-basin (Australia): Implications for the development of Palaeozoic petroleum systems

    SciTech Connect

    Blevin, J.E.; Colwell, J.B.; Kennard, J.M. , Canberra )

    1996-01-01

    An study of the Petrel Sub-basin (Bonaparte Basin) on Australia's northwest margin has identified seven main phases of basin development spanning the Early Cambrian to Tertiary. Each phase was initiated and terminated by distinct, primarily tectonic events that have controlled the structural and stratigraphic evolution of the basin and the development of petroleum systems. These phases include periods of major extension (Early Cambrian, Middle Devonian to early Carboniferous) and compression (Early Devonian, mid-Triassic), as well as rapid and slow subsidence phases in the Early to Late Carboniferous and Late Carboniferous to Triassic, respectively. Basin inversion in the mid-Triassic has been critical in controlling the development of broad anticlinal features that presently reservoir the large, but as yet undeveloped gas/condensate fields Petrel and Tern. An earlier period of minor compression during the late Carboniferous initiated limited movement of Paleozoic salt within the deeper basin, forming salt-cored, low amplitude anticlines in the predominantly carbonate Tanmurra Formation, a play which remains untested. In the southern Petrel Sub-basin, early phases of hydrocarbon generation and fluid migration associated with salt movement are poorly understood. Preliminary results of geochemical studies indicate that there are at least two oil families in Devonian and Carboniferous reservoirs. This suggests multiple source intervals within the deeper flanks of the basin, thus the understanding of sedimentation during early basin phases may be critical in evaluating petroleum systems.

  15. Definition of basin phases in the Petrel Sub-basin (Australia): Implications for the development of Palaeozoic petroleum systems

    SciTech Connect

    Blevin, J.E.; Colwell, J.B.; Kennard, J.M.

    1996-12-31

    An study of the Petrel Sub-basin (Bonaparte Basin) on Australia`s northwest margin has identified seven main phases of basin development spanning the Early Cambrian to Tertiary. Each phase was initiated and terminated by distinct, primarily tectonic events that have controlled the structural and stratigraphic evolution of the basin and the development of petroleum systems. These phases include periods of major extension (Early Cambrian, Middle Devonian to early Carboniferous) and compression (Early Devonian, mid-Triassic), as well as rapid and slow subsidence phases in the Early to Late Carboniferous and Late Carboniferous to Triassic, respectively. Basin inversion in the mid-Triassic has been critical in controlling the development of broad anticlinal features that presently reservoir the large, but as yet undeveloped gas/condensate fields Petrel and Tern. An earlier period of minor compression during the late Carboniferous initiated limited movement of Paleozoic salt within the deeper basin, forming salt-cored, low amplitude anticlines in the predominantly carbonate Tanmurra Formation, a play which remains untested. In the southern Petrel Sub-basin, early phases of hydrocarbon generation and fluid migration associated with salt movement are poorly understood. Preliminary results of geochemical studies indicate that there are at least two oil families in Devonian and Carboniferous reservoirs. This suggests multiple source intervals within the deeper flanks of the basin, thus the understanding of sedimentation during early basin phases may be critical in evaluating petroleum systems.

  16. Petroleum prospectivity of the Canada Basin, Arctic Ocean

    USGS Publications Warehouse

    Grantz, A.; Hart, P.E.

    2012-01-01

    Reconnaissance seismic reflection data indicate that Canada Basin is a >700,000 sq. km. remnant of the Amerasia Basin of the Arctic Ocean that lies south of the Alpha-Mendeleev Large Igneous Province, which was constructed across the northern part of the Amerasia Basin between about 127 and 89-83.5 Ma. Canada Basin was filled by Early Jurassic to Holocene detritus from the Beaufort-Mackenzie Deltaic System, which drains the northern third of interior North America, with sizable contributions from Alaska and Northwest Canada. The basin contains roughly 5 or 6 million cubic km of sediment. Three fourths or more of this volume generates low amplitude seismic reflections, interpreted to represent hemipelagic deposits, which contain lenses to extensive interbeds of moderate amplitude reflections interpreted to represent unconfined turbidite and amalgamated channel deposits.Extrapolation from Arctic Alaska and Northwest Canada suggests that three fourths of the section in Canada Basin is correlative with stratigraphic sequences in these areas that contain intervals of hydrocarbon source rocks. In addition, worldwide heat flow averages suggest that about two thirds of Canada Basin lies in the oil or gas windows. Structural, stratigraphic and combined structural and stratigraphic features of local to regional occurrence offer exploration targets in Canada Basin, and at least one of these contains bright spots. However, deep water (to almost 4000 m), remoteness from harbors and markets, and thick accumulations of seasonal to permanent sea ice (until its possible removal by global warming later this century) will require the discovery of very large deposits for commercial success in most parts of Canada Basin. ?? 2011 Elsevier Ltd.

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

    SciTech Connect

    Wycisk, P. )

    1988-08-01

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

  18. Air Pollution over North-West Bay of Bengal in the Early Post-Monsoon Season Based on NASA MERRAero Data

    NASA Technical Reports Server (NTRS)

    Kishcha, Pavel; DaSilva, Arlindo M.; Starobinets, Boris; Alpert, Pinhas

    2013-01-01

    The MERRA Aerosol Reanalysis (MERRAero) has been recently developed at NASA's Global Modeling Assimilation Office (GMAO). This reanalysis is based on a version of the GEOS-5 model radiatively coupled with GOCART aerosols, and it includes assimilation of bias-corrected Aerosol Optical Thickness (AOT) from the MODIS sensor on both Terra and Aqua satellites. Our main finding is that, in October, in the absence of aerosol sources in north-west Bay of Bengal (BoB), MERRAero showed increasing AOT trends over north-west BoB exceeding those over the east of the Ganges basin. The Ganges basin is characterized by significant population growth accompanied by developing industry, agriculture, and increasing transportation: this has resulted in declining air quality. MERRAero data for the period 2002-2009 was used to study AOT trends over north-west Bay of Bengal (BoB) in the early post-monsoon season. This season is characterized by aerosol transport from the Ganges basin to north-west BoB by prevailing winds; and still significant rainfall of over 150 mmmonth. Different aerosol components showed strong increasing AOT trends over north-west BoB. The following factors contributed to the increasing AOT trend over the area in question in October: an increasing number of days when prevailing winds blew from land to sea, resulting in a drier environment and an increase in air pollution over north-west BoB; wind convergence was observed over north-west BoB causing the accumulation of aerosol particles over that region, when prevailing winds blew from land to sea. MERRAero aerosol reanalysis can be used on a global scale.

  19. Effects of climate change on Pacific Northwest water-related resources: Summary of preliminary findings

    SciTech Connect

    Scott, M.J.; Sands, R.D.; Vail, L.W.; Chatters, J.C.; Neitzel, D.A.; Shankle, S.A.

    1993-12-01

    The Pacific Northwest Case Study is a multi-agency analysis of atmospheric/climatic change impacts on the Pacific Northwest (which includes Washington, Oregon, Idaho, and portions of the Columbia River Basin in Western Montana). The purpose of the case study, which began in fiscal year 1991, was to develop and test analytical tools, as well as to develop an assessment of the effects of climate change on climate-sensitive natural resources of the Pacific Northwest and economic sectors dependent on them. The overall study, jointly funded by the US Department of Energy (DOE) and the US Environmental Protection Agency, was a broad-based, reconnaissance-level study to identify potential climate impacts on agriculture, coastal resources, forest resources, and irrigation in the Pacific Northwest. DOE participated in the reconnaissance study, with responsibility for hydroelectric and water supply issues. While this report briefly discusses a broader array of water issues, attention is mainly focused on three aspects of the water study: (1) the effects of the region`s higher temperatures on the demand for electric power (which in turn puts additional demand on hydroelectric resources of the region); (2) the effects of higher temperatures and changes, both in precipitation amounts and seasonality, on river flows and hydroelectric supply; and (3) the effect of higher temperatures and changed precipitation amounts and seasonality on salmonid resources -- particularly the rearing conditions in tributaries of the Columbia River Basin. Because the meaning of regional climate forecasts is still quite uncertain, most of the preliminary findings are based on sensitivity analyses and historical analog climate scenarios.

  20. Compendium of Low-Cost Pacific Salmon and Steelhead Trout Production Facilities and Practices in the Pacific Northwest.

    SciTech Connect

    Senn, Harry G.

    1984-09-01

    The purpose was to research low capital cost salmon and steelhead trout production facilities and identify those that conform with management goals for the Columbia Basin. The species considered were chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), sockeye salmon (O. nerka), and steelhead trout (Salmo gairdneri). This report provides a comprehensive listing of the facilities, techniques, and equipment used in artificial production in the Pacific Northwest. (ACR)

  1. Habitat and co-occurrence of native and invasive crayfish in the Pacific Northwest, USA

    USGS Publications Warehouse

    Pearl, Christopher A.; Adams, Michael J.; McCreary, Brome

    2013-01-01

    Biological invasions can have dramatic effects on freshwater ecosystems and introduced crayfish can be particularly impacting. We document crayfish distribution in three large hydrographic basins (Rogue, Umpqua, Willamette/Columbia) in the Pacific Northwest USA. We used occupancy analyses to investigate habitat relationships and evidence for displacement of native Pacifastacus leniusculus (Dana, 1852) by two invaders. We found invasive Procambarus clarkii (Girard, 1852), in 51 of 283 sites and in all three hydrographic basins. We found invasive Orconectes n. neglectus (Faxon, 1885) at 68% of sites in the Rogue basin and provide first documentation of their broad distribution in the Umpqua basin. We found P. clarkii in both lentic and lotic habitats, and it was positively associated with manmade sites. P. leniusculus was positively associated with lotic habitats and negatively related to manmade sites. In the Rogue and Umpqua basins, O. n. neglectus and P. leniusculus were similar in their habitat associations. We did not find a negative relationship in site occupancy between O. n. neglectus and P. leniusculus. Our data suggest that P. clarkii has potential to locally displace P. leniusculus. There is still time for preventive measures to limit the spread of the invasive crayfish in this region.

  2. The Northwest Passage opens for bowhead whales.

    PubMed

    Heide-Jørgensen, Mads Peter; Laidre, Kristin L; Quakenbush, Lori T; Citta, John J

    2012-04-23

    The loss of Arctic sea ice is predicted to open up the Northwest Passage, shortening shipping routes and facilitating the exchange of marine organisms between the Atlantic and the Pacific oceans. Here, we present the first observations of distribution overlap of bowhead whales (Balaena mysticetus) from the two oceans in the Northwest Passage, demonstrating this route is already connecting whales from two populations that have been assumed to be separated by sea ice. Previous satellite tracking has demonstrated that bowhead whales from West Greenland and Alaska enter the ice-infested channels of the Canadian High Arctic during summer. In August 2010, two bowhead whales from West Greenland and Alaska entered the Northwest Passage from opposite directions and spent approximately 10 days in the same area, documenting overlap between the two populations. PMID:21937490

  3. The Northwest Passage opens for bowhead whales.

    PubMed

    Heide-Jørgensen, Mads Peter; Laidre, Kristin L; Quakenbush, Lori T; Citta, John J

    2012-04-23

    The loss of Arctic sea ice is predicted to open up the Northwest Passage, shortening shipping routes and facilitating the exchange of marine organisms between the Atlantic and the Pacific oceans. Here, we present the first observations of distribution overlap of bowhead whales (Balaena mysticetus) from the two oceans in the Northwest Passage, demonstrating this route is already connecting whales from two populations that have been assumed to be separated by sea ice. Previous satellite tracking has demonstrated that bowhead whales from West Greenland and Alaska enter the ice-infested channels of the Canadian High Arctic during summer. In August 2010, two bowhead whales from West Greenland and Alaska entered the Northwest Passage from opposite directions and spent approximately 10 days in the same area, documenting overlap between the two populations.

  4. 1996 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    1996-12-01

    The Pacific Northwest Loads and Resources Study (White Book) is published annually by BPA and establishes the planning basis for supplying electricity to customers. It serves a dual purpose. First, the White Book presents projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. Second, the White Book serves as a benchmark for annual BPA determinations made pursuant to the 1981 regional power sales contracts. Specifically, BPA uses the information in the White Book for determining the notice required when customers request to increase or decrease the amount of power purchased from BPA. Aside from these purposes, the White Book is used for input to BPA`s resource planning process. The White Book compiles information obtained from several formalized resource planning reports and data submittals, including those from the Northwest Power Planning Council (Council) and the Pacific Northwest Utilities Conference Committee (PNUCC). 11 figs., 12 tabs.

  5. The Northwest Passage opens for bowhead whales

    PubMed Central

    Heide-Jørgensen, Mads Peter; Laidre, Kristin L.; Quakenbush, Lori T.; Citta, John J.

    2012-01-01

    The loss of Arctic sea ice is predicted to open up the Northwest Passage, shortening shipping routes and facilitating the exchange of marine organisms between the Atlantic and the Pacific oceans. Here, we present the first observations of distribution overlap of bowhead whales (Balaena mysticetus) from the two oceans in the Northwest Passage, demonstrating this route is already connecting whales from two populations that have been assumed to be separated by sea ice. Previous satellite tracking has demonstrated that bowhead whales from West Greenland and Alaska enter the ice-infested channels of the Canadian High Arctic during summer. In August 2010, two bowhead whales from West Greenland and Alaska entered the Northwest Passage from opposite directions and spent approximately 10 days in the same area, documenting overlap between the two populations. PMID:21937490

  6. Climatic and Hydrologic Modeling in the Yellow River Basin in China Dr. Shourong Wang wangsr@cma.gov.cn China Meteorological Administration No.46, Zhongguancun Nandajie, Haidian District, Beijing 100081, China Dr. Ruby LEUNG, Pacific Northwest National Laboratory, Richland, Washington 99352, USA

    NASA Astrophysics Data System (ADS)

    Wang, S.

    2012-12-01

    In order to enhance climatic and hydrologic prediction and assessment ability in the Yellow River Basin, the climatic and hydrologic modeling system is developed based on a joint international research. The system includes three sub-modeling systems, the seasonal climatic modeling system, the climate change modeling system, and the hydrologic modeling system. The seasonal climatic modeling system is composed of a regional climate model WRF3.3.1 developed by PNNL in 2011, with domain cover whole China and surrounding areas and horizontal resolution of 30 km, the Global general circulation models (GCMs) developed by China National Climate Center (NCC), providing lateral boundary conditions to WRF3.3.1, and both dynamic and statistic downscaling tools for providing detail modeling results in the Yellow River Basin. The climate change modeling system is composed of a regional climate model RegCM4.0 modified by NCC, with domain and horizontal resolution similar to WRF3.3.1, four GCMs MIROC3.2, ECHAM5, HadCM3 and NCC-CSM1.1, providing lateral boundary conditions to RegCM4.0, respectively, for comparing the nest modeling results, and also the downscaling tools. The hydrologic modeling system is composed of a large scale semi-distributed hydrologic mode VIC(Variable Infiltration Capacity) modified by PNNL, with domain cover whole Yellow River Basin and horizontal resolution of 50 km, and a distributed hydrologic mode DHSVM3.0 (Distributed Hydrology-Soil-vegetation Mode) also modified by PNNL, with domain cover the headstream of Yellow River Basin and horizontal resolution of 0.5 km. Both VIC and DHSVM3.0 are driven by the outputs of WRF3.3.1 and RegCM4.0, and provide seasonal hydrologic predictions and future hydrologic projections under IPCC AR5 climate change scenarios SRES RCP8.5 and RCP4.5. Now the simulated seasonal climatic and hydrologic results are compared and verified by recorded data sets, and VIC and DHSVM3.0 are running for the future hydrologic simulation

  7. Natural phosphorus sources for the Pacific Northwest

    USGS Publications Warehouse

    Johnson, Hank

    2011-01-01

    Phosphorus is a naturally occurring element found in all rocks; the amount varies by the type of rock. The amount of phosphorus in sediments is expected to be correlated with the amount of phosphorus in the parent rocks. Streambed sediment collected by the National Uranium Resource Evaluation (NURE) Program were used to estimate the variation of phosphorus across the Pacific Northwest. This file provides an estimate of the mean concentration of phosphorus in soils for each incremental catchment of the USGS Pacific Northwest SPARROW model.

  8. Early Eocene uplift of southernmost San Joaquin basin, California

    SciTech Connect

    Reid, S.A.; Cox, B.F.

    1989-04-01

    Stratigraphic studies in the southern San Joaquin basin and in the El Paso Mountains of the southwestern Great Basin corroborate a hypothesized early Eocene regional uplift event. Eocene uplift and erosion of the southernmost San Joaquin basin south of Bakersfield were recently proposed because an early Paleogene fluviodeltaic sequence in the El Paso Mountains (Goler Formation) apparently had no seaward counterpart to the southwest. New microfossil data (coccoliths) indicate that marine deposits near the top of the Goler Formation are uppermost Paleocene (nannofossil zone CP8) rather than lower Eocene, as reported previously. These data (1) confirm that the oldest known Tertiary strata south of Bakersfield (Eocene Tejon Formation) are younger than the uppermost Goler Formation and (2) seem to restrict uplift to the earliest Eocene. The authors propose that the uppermost Cretaceous and Paleocene deposits were eroded and the Mushrush trough was cut and filled mainly in response to earliest Eocene uplift. The uplift was transverse to the northwest-trending forearc basin. Thus, it was distinct from late early Eocene (pre-Comengine Formation) regional tilting and uplift, which produced northwest-trending structures. Early Eocene uplift probably played only a minor role in the southward termination of pre-Maastrichtian parts of the forearc basin, which they instead attribute to massive uplift of the southernmost Sierra Nevada during the early(.) Late Cretaceous.

  9. Cenozoic pull-apart basins in southwest Montana

    SciTech Connect

    Ruppel, E.T. )

    1991-06-01

    Faults and fault zones bounding the mountain ranges of southwest Montana commonly have been described as normal faults, and the region has been considered to be a northern extension of the Basin and Range. New geologic mapping suggests, however, that Cenozoic movements along most of the zones of steep faults in southwest Montana and in east-central Idaho have been strike-slip, and the intermontane basins appear to be pull-aparts. The principal fault zones trend about north, northwest, east, and north-northeast; the north-trending zones are Cenozoic in age, but the others are of Archean ancestry and are rooted in basement rocks. These faults break the region into rhomboidal mountain blocks separated by broad basins with parallel sides. The basins are as much as 5,000 m deep, and their floors are deeply indented by centers of subsidence wherre they are crossed by major fault zones. The basins are floored by Archean or Proterozoic rocks and are filled with tuffaceous sedimentary rocks of late Oligocene to late Miocene age. The Big Hole basin and the smaller basins in upper Grasshopper Creek and Horse Prairie are interpreted to be pull-aparts between zones of east-trending right-lateral faults. The cratonic basins farther east in southwest Montana are interpreted to be basement-floored openings between mountain blocks that have been separated by subcrustal flow to the northwest. The interpretations suggest that significant accumulations of oil or gas are not likely to be found in this region.

  10. LODGEPOLE BRIDGE, SOUTH ELEVATION, FACING NORTHWEST Generals Highway, Lodge ...

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

    LODGEPOLE BRIDGE, SOUTH ELEVATION, FACING NORTHWEST - Generals Highway, Lodge Pole Bridge, Spanning Marble Fork of Kaweah River, approximately 21 miles northwest of Ash Mountain Entrance, Three Rivers, Tulare County, CA

  11. 69. TURBINE BUILDING (LOCATION N), THIRD LEVEL LOOKING NORTHWEST SHOWING ...

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

    69. TURBINE BUILDING (LOCATION N), THIRD LEVEL LOOKING NORTHWEST SHOWING BASE OF CONDENSOR AND RIVER WATER OUTLET PIPE - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  12. 8. VIEW FROM NORTHWEST OF CONDENSATE STORAGE TANK (LEFT), PRIMARY ...

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

    8. VIEW FROM NORTHWEST OF CONDENSATE STORAGE TANK (LEFT), PRIMARY WATER STORAGE TANK (CENTER), CANAL WATER STORAGE TANK (RIGHT) (LOCATIONS E,F,D) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  13. 4. VIEW LOOKING NORTHWEST OF FUEL HANDLING BUILDING (CENTER), REACTOR ...

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

    4. VIEW LOOKING NORTHWEST OF FUEL HANDLING BUILDING (CENTER), REACTOR SERVICE BUILDING (RIGHT), MACHINE SHOP (LEFT) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  14. 46. AUXILIARY CHAMBER (EAST END), LOOKING NORTHWEST AT STEAM AND ...

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

    46. AUXILIARY CHAMBER (EAST END), LOOKING NORTHWEST AT STEAM AND FEEDWATER PIPING AND PRESSURIZER AND FLASH/BLOWOFF TANK ROOMS (LOCATION EEE) - Shippingport Atomic Power Station, On Ohio River, 25 miles Northwest of Pittsburgh, Shippingport, Beaver County, PA

  15. 3. Northwest side and southwest rear of addition. View to ...

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

    3. Northwest side and southwest rear of addition. View to east. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  16. 6. General interior overview of addition. View to northwest. ...

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

    6. General interior overview of addition. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  17. 2. Southeast side of addition. View to northwest. Offutt ...

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

    2. Southeast side of addition. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  18. 55. Downstream face of diversion dam looking northwest. Photographer Mark ...

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

    55. Downstream face of diversion dam looking northwest. Photographer Mark Durben, 1986. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  19. Photocopy of original blackandwhite silver gelatin print, VIEW FROM NORTHWEST ...

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

    Photocopy of original black-and-white silver gelatin print, VIEW FROM NORTHWEST CORNER, April 1, 1929, photographer Commercial Photo Company - Internal Revenue Service Headquarters Building, 1111 Constitution Avenue Northwest, Washington, District of Columbia, DC

  20. 9. INTERIOR, TOOL ROOM IN NORTHWEST CORNER OF 'CENTRAL NORTH ...

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

    9. INTERIOR, TOOL ROOM IN NORTHWEST CORNER OF 'CENTRAL NORTH WING,' FROM SOUTHEAST CORNER OF ROOM, LOOKING NORTHWEST. - Oakland Naval Supply Center, Lumber Storage & Box Factory, East of Fifth Street, between H & I Streets, Oakland, Alameda County, CA

  1. 6. Keeper's house, southeast parlor, looking northwest Pumpkin Island ...

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

    6. Keeper's house, southeast parlor, looking northwest - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  2. 5. Light tower and keeper's house, view southeast, northwest and ...

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

    5. Light tower and keeper's house, view southeast, northwest and southwest sides - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  3. 3. Keeper's house, view northwest, southeast and northeast sides ...

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

    3. Keeper's house, view northwest, southeast and northeast sides - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  4. 7. Light tower, interior from entrance, looking northwest Pumpkin ...

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

    7. Light tower, interior from entrance, looking northwest - Pumpkin Island Light Station, Pumpkin Island, at northern end of Eggemoggin Beach, off northwest end of Little Deer Island, Eggemoggin, Hancock County, ME

  5. View of northwest elevation of Building No. 42. Parking Area ...

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

    View of northwest elevation of Building No. 42. Parking Area No. 28 at front right. Looking southeast - Easter Hill Village, Building No. 42, Northwest corner of Foothill Avenue & South Twenty-eighth Street, Richmond, Contra Costa County, CA

  6. 3. BARRACKS, NEXT TO BASKETBALL COURT, LEFT SIDE, LOOKING NORTHWEST. ...

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

    3. BARRACKS, NEXT TO BASKETBALL COURT, LEFT SIDE, LOOKING NORTHWEST. - NIKE Missile Base SL-40, Barracks No. 1, North end of base, southest of Basketball Court & northwest of Barracks No. 2, Hecker, Monroe County, IL

  7. 77 FR 50979 - Northwest Forest Plan Provincial Advisory Committees

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-23

    ...; ] DEPARTMENT OF AGRICULTURE Office of the Secretary Northwest Forest Plan Provincial Advisory Committees AGENCY... United States Department of Agriculture (USDA) announces solicitation for nominations to fill vacancies... Agriculture established the Pacific Northwest Provincial Advisory Committees (PACs) to the...

  8. View of the northwest corner of the Justice Department Building ...

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

    View of the northwest corner of the Justice Department Building at Tenth Street and Pennsylvania Avenue - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  9. 3. Interior view southeast to northwest showing space heater in ...

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

    3. Interior view southeast to northwest showing space heater in northwest corner - Fort Hood, World War II Temporary Buildings, Dispatcher House, North of Park Avenue at Forty-ninth Street, Killeen, Bell County, TX

  10. 1. VIEW TO NORTHWEST, FRONT AND SIDE. Vanadium Corporation ...

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

    1. VIEW TO NORTHWEST, FRONT AND SIDE. - Vanadium Corporation of America (VCA) Naturita Mill, Mill Warehouse, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  11. 14. VIEW TO NORTHWEST, SMALL ROASTER (DISMANTLED). Vanadium Corporation ...

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

    14. VIEW TO NORTHWEST, SMALL ROASTER (DISMANTLED). - Vanadium Corporation of America (VCA) Naturita Mill, 3 miles Northwest of Naturita, between Highway 141 & San Miguel River, Naturita, Montrose County, CO

  12. INTERIOR OF VESTIBULE OF STANDARDIZING MAGNETIC OBSERVATORY, LOOKING NORTHWEST. ...

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

    INTERIOR OF VESTIBULE OF STANDARDIZING MAGNETIC OBSERVATORY, LOOKING NORTHWEST. - Carnegie Institution of Washington, Department of Terrestrial Magnetism, Standardizing Magnetic Observatory, 5241 Broad Branch Drive Northwest, Washington, District of Columbia, DC

  13. INTERIOR ELEVATION LOOKING TOWARD THE LEANTO OF THE NORTHWEST SIDE. ...

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

    INTERIOR ELEVATION LOOKING TOWARD THE LEAN-TO OF THE NORTHWEST SIDE. VIEW FACING NORTHWEST. - U.S. Naval Base, Pearl Harbor, Seaplane Hangar, Lexington Boulevard, south of Enterprise Street, Pearl City, Honolulu County, HI

  14. The Bicentennial of the Northwest Ordinance of 1787.

    ERIC Educational Resources Information Center

    Patrick, John J.

    1987-01-01

    Reviews the political history surrounding the development of the Northwest Ordinance of 1787. Includes a shortened and simplified version of the major articles of the Ordinance. Identifies three instructional resources for teaching about the Northwest Ordinance in secondary schools. (JDH)

  15. 2. SOUTH VIEW OF NORTHWEST AND NORTHEAST SIDES (NORTH CORNER). ...

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

    2. SOUTH VIEW OF NORTHWEST AND NORTHEAST SIDES (NORTH CORNER). NORTHWEST SIDE OF ASSAY OFFICE ON LEFT - Juniata Mill Complex, Mine Office, 22.5 miles Southwest of Hawthorne, between Aurora Crater & Aurora Peak, Hawthorne, Mineral County, NV

  16. FEATURE 4, ARMCO HUT, INTERIOR , VIEW FACING NORTHWEST. ...

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

    FEATURE 4, ARMCO HUT, INTERIOR , VIEW FACING NORTHWEST. - Naval Air Station Barbers Point, Anti-Aircraft Battery Complex-ARMCO Hut, East of Coral Sea Road, northwest of Hamilton Road, Ewa, Honolulu County, HI

  17. View of the Executive Director's Office (in the northwest corner ...

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

    View of the Executive Director's Office (in the northwest corner of the second floor), looking from the northwest - Sewall-Belmont House, 144 Constitution Avenue, Northeast, Washington, District of Columbia, DC

  18. Solar Energy for Pacific Northwest Buildings.

    ERIC Educational Resources Information Center

    Reynolds, John S.

    Data presented in this report indicate that solar space and water heating are possible in the Pacific Northwest. The first section of the report contains solar records from several stations in the region illustrating space heating needs that could be met, on an average daily basis, by solar energy. The data are summarized, and some preliminary…

  19. Pulse crop diseases in the Pacific Northwest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The United Nations declared that 2016 is the International Year of Pulses (IYP). This UN declaration of IYP will certainly increase awareness of pulses and likely position pulses as a primary source of protein and other essential nutrients for human diets. The US Pacific Northwest region (Idaho, Or...

  20. Distance Education Resource Directory for Northwest Schools.

    ERIC Educational Resources Information Center

    Holznagel, Donald C.

    This directory is designed to address the need for technology planning in the curriculum, as well as to provide information about the distance education technology options available for school districts in the Northwest states of Alaska, Idaho, Montana, Oregon, and Washington. The following areas are covered: satellite television, two-way audio;…

  1. SCIENCE, POLICY, AND PACIFIC NORTHWEST SALMON RECOVERY

    EPA Science Inventory

    Throughout the Pacific Northwest, since 1850, all wild salmon runs have declined and some have disappeared. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds of millions of dollars continue to be spent in variou...

  2. Endangered Species in the Pacific Northwest.

    ERIC Educational Resources Information Center

    Clearing: Nature and Learning in the Pacific Northwest, 1985

    1985-01-01

    Suggests that students can learn how society works by studying threatened and endangered plant and animal species which occur in the local environments. Pictures, descriptions, habitats, and niche information are given for 21 threatened or endangered species of the Pacific Northwest. (DH)

  3. The Northwest Ordinance, 1787: A Bicentennial Handbook.

    ERIC Educational Resources Information Center

    Taylor, Robert M., Jr., Ed.

    The essays and annotations in this publication provide an opportunity for citizens and students to consider not only the history of the Northwest Ordinance but also basic and enduring issues in U.S. political life. The book is divided into three main parts. The first part provides a background to the Ordinance and its passage by the Confederation…

  4. The Pacific northwest stream quality assessment

    USGS Publications Warehouse

    Van Metre, Peter C.; Morace, Jennifer L.; Sheibley, Rich W.

    2015-01-01

    The Pacific Northwest study will be the third regional study by the NAWQA program, and it will be of similar design and scope as the first two—the Midwest in 2013 and the Southeast in 2014 (Van Metre and others, 2012, 2014).

  5. Learning: Tradition & Change in the Northwest Territories.

    ERIC Educational Resources Information Center

    Northwest Territories Legislative Assembly, Yellowknife. Special Committee on Education.

    In 1981-82 the Legislative Assembly's Special Committee on Education held 43 public hearings throughout the Northwest Territories to gather information on all aspects of public concern about education. Written in English and Inupiaq, this document outlines problems related to: (1) preparation for a traditional Native life versus preparation for…

  6. Raindrop Characteristics in the Pacific Northwest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The U.S. Pacific Northwest, influenced by maritime air masses for most of the year, generally exhibits low rainfall intensities. The drop-size characteristics of such low-intensity storms are rarely studied. An investigation of natural drop sizes and their distribution was conducted at the Palouse ...

  7. SCIENCE, POLITICS, AND PACIFIC NORTHWEST SALMON RECOVERY

    EPA Science Inventory

    Throughout the Pacific Northwest, since 1850, all wild salmon runs have declined and some have disappeared. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds of millions of dollars continue to be spent in variou...

  8. 1999 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    1999-12-01

    The Pacific Northwest Loads and Resources Study (White Book) is published annually by BPA and establishes the planning basis for supplying electricity to customers. It serves a dual purpose. First, the White Book presents projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. Second, the White Book serves as a benchmark for annual BPA determinations made pursuant to its regional power sales contracts. Specifically, BPA uses the information in the White Book for determining the notice required when customers request to increase or decrease the amount of power purchased from BPA. The White Book will not be used in calculations for the 2002 regional power sales contract subscription process. The White Book compiles information obtained from several formalized resource planning reports and data submittals, including those from the Northwest Power Planning Council (Council) and the Pacific Northwest Utilities Conference Committee (PNUCC). The White Book is not an operational planning guide, nor is it used for determining BPA revenues. Operation of the Federal Columbia River Power System (FCRPS) is based on a set of criteria different from that used for resource planning decisions. Operational planning is dependent upon real-time or near-term knowledge of system conditions, including expectations of river flows and runoff, market opportunities, availability of reservoir storage, energy exchanges, and other factors affecting the dynamics of operating a power system. In this loads and resources study, resource availability is compared with a medium forecast of electricity consumption. The forecasted future electricity demands--firm loads--are subtracted from the projected capability of existing and ''contracted for'' resources to determine whether BPA and the region will be surplus or deficit. If Federal system resources are greater than loads in any particular year or month, there is a surplus of energy

  9. 1991 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    1991-12-01

    This study establishes the Bonneville Power Administration's (BPA) planning basis for supplying electricity to BPA customers. The Loads and Resources Study is presented in three documents: (1) this summary of federal system and Pacific Northwest region loads and resources; (2) a technical appendix detailing forecasted Pacific Northwest economic trends and loads, and (3) a technical appendix detailing the loads and resources for each major Pacific Northwest generating utility. This analysis updates our 1990 study. BPS's long-range planning incorporates resource availability with a range of forecasted electrical consumption. The forecasted future electrical demands-firm loads--are subtracted from the projected capability of existing resources to determine whether BPA and the region will be surplus or deficit. If resources are greater than loads in any particular year or month, there is a surplus of energy and/or capacity, which BPA can sell to increase revenues. Conversely, if firm loads exceed available resources, there is a deficit of energy and/or capacity, then additional conservation, contract purchases, or generating resources will be needed to meet load growth. This study analyzes the Pacific Northwest's projected loads and available generating resources in two parts: (1) the loads and resources of the federal system, for which BPA is the marketing agency; and (2) the larger Pacific Northwest regional profile, which includes loads and resources in addition to the federal system. This study presents the federal system and regional analyses for five load forecasts: high, medium-high, medium, medium-low, and low. This analysis projects the yearly average energy consumption and resource availability for 1992- 2012.

  10. 76 FR 4890 - Northwest Pipeline GP; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-27

    ... Energy Regulatory Commission Northwest Pipeline GP; Notice of Application January 20, 2011. Take notice that on January 11, 2011, Northwest Pipeline GP (Northwest), 295 Chipeta Way, Salt Lake City, Utah... Project consists of: Abandonment in place of approximately 15 miles of 16-inch diameter pipeline...

  11. 77 FR 37663 - Northwest Pipeline GP; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-22

    ... Energy Regulatory Commission Northwest Pipeline GP; Notice of Application Take notice that on June 4, 2011, Northwest Pipeline GP (Northwest), 295 Chipeta Way, Salt Lake City, Utah 84108, filed in Docket... by removal of 10-inch diameter pipeline segments between mileposts 0.00 and 2.01 and mileposts...

  12. 7 CFR 319.8-13 - From Northwest Mexico.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false From Northwest Mexico. 319.8-13 Section 319.8-13... for the Entry of Cotton and Covers from Mexico § 319.8-13 From Northwest Mexico. Contingent upon continued freedom of Northwest Mexico and of the West Coast of Mexico from infestations of the pink...

  13. 78 FR 25067 - Northwest Pipeline GP; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ... April 12, 2013, Northwest Pipeline GP (Northwest), 295 Chipeta Way, Salt Lake City, Utah 84108, filed in... authorizing Northwest to construct and operate the Blue Water Liquefied Natural Gas (LNG) Meter Station and associated appurtenances at Benton County, Washington. The Blue Water LNG Meter Station will include...

  14. 7 CFR 1124.2 - Pacific Northwest marketing area.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Pacific Northwest marketing area. 1124.2 Section 1124... SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA Order Regulating Handling Definitions § 1124.2 Pacific Northwest marketing area....

  15. 7 CFR 319.8-13 - From Northwest Mexico.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false From Northwest Mexico. 319.8-13 Section 319.8-13... for the Entry of Cotton and Covers from Mexico § 319.8-13 From Northwest Mexico. Contingent upon continued freedom of Northwest Mexico and of the West Coast of Mexico from infestations of the pink...

  16. 4. View of junction from the northwest looking southeast over ...

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

    4. View of junction from the northwest looking southeast over the northwest leg and northwest ramp of the cloverleaf toward the western side of bridge no. 5820. - Cloverleaf Interchange, Junction of Trunk Highways 52, 3, & 55, Inver Grove Heights, Dakota County, MN

  17. Tectonic differences between eastern and western sub-basins of the Qiongdongnan Basin and their dynamics

    NASA Astrophysics Data System (ADS)

    Liu, Jianbao; Sun, Zhen; Wang, Zhenfeng; Sun, Zhipeng; Zhao, Zhongxian; Wang, Zhangwen; Zhang, Cuimei; Qiu, Ning; Zhang, Jiangyang

    2015-03-01

    The central depression of the Qiongdongnan Basin can be divided into the eastern and western sub-basins by the Lingshui-Songnan paleo-uplift. To the northwest, the orientation of the faults turns from NE, to EW, and later to NW; In the southwest, the orientation of the faults turns from NE, to NNE, and then to NW, making the central depression much wider towards the west. In the eastern sub-basin, the NE-striking faults and the EW-striking faults made up an echelon, making the central depression turn wider towards the east. Fault activity rates indicate that faulting spreads gradually from both the east and west sides to the middle of the basin. Hence, extensional stress in the eastern sub-basin may be related to the South China Sea spreading system, whereas the western sub-basin was more under the effect of the activity of the Red River Fault. The extreme crustal stretching in the eastern sub-basin was probably related to magmatic setting. It seems that there are three periods of magmatic events that occurred in the eastern sub-basin. In the eastern part of the southern depression, the deformed strata indicate that the magma may have intruded into the strata along faults around T60 (23.3 Ma). The second magmatic event occurred earlier than 10.5 Ma, which induced the accelerated subsidence. The final magmatic event commenced later than 10 Ma, which led to today's high heat flow. As for the western sub-basin, the crust thickened southward, and there seemed to be a southeastward lower crustal flow, which happened during continental breakup which was possibly superimposed by a later lower crustal flow induced by the isostatic compensation of massive sedimentation caused by the right lateral slipping of the Red River Fault. Under the huge thick sediment, super pressure developed in the western sub-basin. In summary, the eastern sub-basin was mainly affected by the South China Sea spreading system and a magma setting, whereas the western sub-basin had a closer

  18. The Devonian Lower Carboniferous succession in Northwest Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Meor, Hakif Hassan; Lee, Chai Peng

    2005-03-01

    A new stratigraphic nomenclature is proposed for the approximately 600 m thick, mainly clastic transitional sequence between the underlying Mempelam Limestone and overlying Kubang Pasu/Singa Formation in northwest Peninsular Malaysia. This sequence represents shallow marine deposits of the continental margin of the Sibumasu Terrane during the Middle Palaeozoic (Devonian-Carboniferous). It is separated into several formations. The Timah Tasoh Formation is an approximately 76 m sequence consisting of 40 m of laminated tentaculitid shales at the base, containing Monograptus yukonensis Jackson and Lenz and Nowakia (Turkestanella) acuaria Alberti, giving an Early Devonian (Pragian-Emsian) age, and about 36 m of rhythmically interbedded, light coloured argillo-arenites. The Chepor Formation is about 90 m thick and consists mainly of thick red mudstone interbedded with sandstone beds, of Middle to Late Devonian age. A new limestone unit is recognized and named the Sanai Limestone, which contains conodonts of Famennian age. The Binjal Formation consists of red and white mudstone interbedded with sandstone beds showing Bouma sequences. The Telaga Jatoh Formation is 9 m thick and consists mainly of radiolarian chert. The Wang Kelian Formation is composed of thick red mudstone beds interbedded with silty sandstone, and contain fossils indicative of an Early Carboniferous (Visean) age. The succession was deposited on the outer shelf, with depositional environments vertically fluctuating from prodelta to basinal marine. The Devonian-Carboniferous boundary is exposed at Hutan Aji and Kampung Guar Jentik, and indicates a major regressive event during the latest Devonian.

  19. Fluvial response to the Paleocene-Eocene Thermal Maximum in northwest Wyoming and western Colorado, USA

    NASA Astrophysics Data System (ADS)

    Foreman, B. Z.; Heller, P.; Clementz, M. T.

    2011-12-01

    The Willwood and Wasatch formations of northwest Wyoming and western Colorado record alluvial deposition within the intermontane Bighorn and Piceance Creek basins, respectively. Both display substantial shifts in the character of fluvial sand-bodies coincident with an abrupt negative carbon isotope excursion linked to the Paleocene Eocene Thermal Maximum (PETM) climate change event at ~55 Ma. In the northern Bighorn Basin, an anomalously thick and laterally persistent multi-story fluvial sand-body crops out within the main body of the PETM isotopic excursion. The internal architecture and lithofacies within the sand-body are similar to pre- and post-PETM sand-bodies, and mean paleo-flow depths do not appear to change substantially. The most significant change is the increase in vertical and lateral amalgamation within the PETM sand-body. Long-term basin sedimentation rates are constant spanning the event implying a transient increase in channel mobility via avulsion and meandering processes during the PETM, which preferentially evacuated fine-grained overbank material out of the basin to the north. Similarly, fluvial sand-bodies are more laterally and vertically amalgamated during the PETM in the Piceance Creek Basin. Yet here the sand-bodies are a recurrent phenomenon throughout the PETM, persist after the PETM, and show dramatic internal architectural changes. Flow depths increase by ~50% and are twice as variable during the PETM, lithofacies are dominated by upper flow regime structures, and crevasse splay deposits are ubiquitous in the associated floodplain strata. In both basins enhanced channel mobility was likely facilitated by a combination of vegetation overturn and alteration of precipitation patterns. Sediment stored higher in the catchment and on related hill-slopes was released, choked basin river systems, instigated greater in-channel deposition, and caused more rapid avulsions. Introduction of coarser sediment loads and vegetation change would have

  20. Assessment of Geothermal Resources for Electric Generation in the Pacific Northwest, Draft Issue Paper for the Northwest Power Planning Council

    SciTech Connect

    Geyer, John D.; Kellerman, L.M.; Bloomquist, R.G.

    1989-09-26

    This document reviews the geothermal history, technology, costs, and Pacific Northwest potentials. The report discusses geothermal generation, geothermal resources in the Pacific Northwest, cost and operating characteristics of geothermal power plants, environmental effects of geothermal generation, and prospects for development in the Pacific Northwest. This report was prepared expressly for use by the Northwest Power Planning Council. The report contains numerous references at the end of the document. [DJE-2005

  1. Application of structures mapped from Landsat imagery to exploration for stratigraphic traps in Paradox basin

    SciTech Connect

    Merin, I.S.; Michael, R.C.

    1985-02-01

    Significant quantities of petroleum occur in algal buildups of Pennsylvanian age in the Paradox basin. Isopach and lithofacies mapping by others suggest that low-relief paleostructures appear to have controlled Pennsylvanian sea-floor topography and thus the distribution of the buildups. Several workers have reported that these paleostructures trend northwest and northeast. Therefore, the basin can be visualized as a mosaic of fault blocks that were differentially active through geologic time. The buildups are elongate northwest, and their distribution and overall shape appear to be controlled by northwest-trending paleostructures. Some larger buildups (i.e., Ismay) show local northeast-trending thicks within an overall northwest-trending buildup. Examination of Landsat imagery revealed an extensive network of northwest-and northeast-trending lineaments that parallel linear patterns apparent from aeromagnetic, gravity, and subsurface isopach data. Additionally, outcrops along selected lineaments contain fractures that parallel these lineaments, suggesting that the lineaments are related to fundamental (i.e., basement) fracture zones along which algal buildups may have developed. Comparison of the fracture network to the distribution of algal thickening reveals these buildups occur predominantly along northwest-trending lineaments. Local disruptions within and apparent terminations of the buildups correspond to cross-cutting northeast-trending lineaments. This relationship provides guidance to locating prospective algal buildups. Integration of these data with detailed subsurface mapping can refine some leads into prospects. Several of these features have been successfully drilled.

  2. Evolution of the San Jorge basin, Argentina

    SciTech Connect

    Fitzgerald, M.G. ); Uliana, M.A. ); Biddle, K.T. ); Mitchum, R.M. Jr.

    1990-06-01

    The San Jorge basin, although small, is the most important hydrocarbon-producing basin in Argentina. Remaining untested potential is high because of the presence of good source rock, favorable structural complexity, and multiple reservoirs. Reservoir quality is commonly low because of the highly tuffaceous sandstones. The sedimentary fill of the basin is closely related to its tectonic history. Northwest-southeast-trending grabens formed and filled during a Triassic and Early Jurassic early rift phase, climaxing with a pervasive Middle Jurassic volcanic episode; continued growth and filling of the basin occurred during a Late Jurassic-earliest Cretaceous late rift phase and Cretaceous early and late sag phases. Late Cretaceous-early Tertiary extension set up many of the present-day structural traps along normal faults. Middle Tertiary Andean compression produced the narrow, north-south San Bernardo structural belt, which exhibits reversed movement on older, normal, graben-bounding faults and on local, low-angle thrust faults. Marked early to middle Tertiary erosion produced a significant unconformity within Cretaceous beds around basin margins. Origin of Upper Jurassic and lowermost Cretaceous sedimentary fill is primarily lacustrine or fluvial in origin. Lacustrine, organic-rich black shales are fringed by oolitic and other limestones and fluvial-deltaic sandstones derived mostly from the north. A significant southern source of sand existed during the Valanginian. Interbedded marine shales occur mostly to the west toward a presumed marine seaway connection to the northern Magallanes basin. Middle to Upper Cretaceous sedimentary rocks, sourced mostly from the north, are mainly fluvial sandstone-shale successions with some minor lacustrine influence. Reservoir quality glauconitic sands were deposited during a Late Cretaceous-early Tertiary marine incursion from the Atlantic.

  3. Tectonic history of the Illinois basin

    SciTech Connect

    Kolata, D.R.; Nelson, J.W. )

    1990-05-01

    The Illinois basin began as a failed rift that developed during breakup of a supercontinent approximately 550 Ma. A rift basin in the southernmost part of the present Illinois basin subsided rapidly and filled with about 3,000 m of probable Early and Middle Cambrian sediments. By the Late Cambrian, the rift-bounding faults became inactive and a broad relatively slowly subsiding embayment, extending well beyond the rift and open to the Iapetus Ocean, persisted through most of the Paleozoic Era. Widespread deformation swept through the proto-Illinois basin beginning in the latest Mississippian, continuing to the end of the Paleozoic Era. Uplift of basement fault blocks resulted in the formation of many major folds and faults. The timing of deformation and location of these structures in the forelands of the Ouachita and Alleghanian orogenic belts suggest that much of the deformation resulted from continental collision between North America and Gondwana. The associated compressional stress reactivated the ancient rift-bounding faults, upthrusting the northern edge of a crustal block approximately 1,000 m within the rift. Concurrently, dikes (radiometrically dated as Early Permian), sills, and explosion breccias formed in or adjacent to the reactivated rift. Subsequent extensional stress, probably associated with breakup of Pangea, caused the crustal block within the rift to sink back to near its original position. High-angle, northeast- to east-west-trending normal faults, with as much as 1,000 m of displacement, formed in the southern part of the basin. These faults displace some of the northwest trending Early Permian dikes. Structural closure of the southern end of the Illinois basin was caused by uplift of the Pascola arch sometime between the Late Pennsylvanian and Late Cretaceous.

  4. Hylton northwest field's tectonic effect on Suggs Ellenburger producing area, Nolan County, Texas

    SciTech Connect

    Hoffacker, B.F. Jr.

    1987-02-01

    An evaluation of the geology of Hylton Northwest field in southeastern Nolan County, Texas, indicates that the pre-Pennsylvanian tectonics associated with this field may have affected the producing zone of Suggs Ellenburger field 6 mi (9 km) west. Both fields are located along the Fort Chadbourne fault system of the Eastern shelf of the Midland basin. The study of the depositional environment of the Suggs Ellenburger field reveals some interesting aspects of the tectonostratigraphic terrane that appears to have in part influenced the development of the reservoir rock. The tectonics of the Cambrian-Ordovician (Ellenburger) period in Hylton Northwest field created a southwest-trending fault system with associated fractures. The fractures allowed percolating surface waters to leach carbonate rocks in the area, creating vuggy secondary porosity in the intercrystalline rock fabric. The faults were modified to a karst topography by periods of subaerial erosion of the Cambrian-Ordovician depositional plain. Sea level fluctuations that occurred in the area were associated with the alternating uplift and subsidence of the Hylton Northwest field's tectonic feature. As a result, environmental zones of porosity with varying vertical subaerial erosion formed within the overall Cambrian-Ordovician (Ellenburger) interval. The producing zone of the Suggs Ellenburger field occurs at approximately 6,400 ft (1,951 m).

  5. Seismic stratigraphy and subsidence analysis in the Barrow-Dampier subbasin, northwest Australia

    SciTech Connect

    Westphal, H.; Aigner, T.

    1997-10-01

    The objective of this study is to analyze the basin-fill history of the Barrow-Dampier Subbasin (Northwest Shelf, Australia) as a spectacular and complex example of the stratigraphic record of continental breakup. From the Permian until the Holocene, the Barrow-Dampier Subbasin underwent development from a continental sedimentary basin located on the Gondwana continent to a rift graben. When extensional movement ceased, the subbasin developed as a passive continental margin. This study, based on marine seismic data (about 600 km) and logs of 20 wells, includes a seismic stratigraphic analysis tied to wells in the vicinity, chronostratigraphic charts, and the calculation of subsidence curves. The basin fill is characterized by a hierarchically organized architecture. The largest scale are four tectonic-stratigraphic units: prerift (Upper Permian to Plienobachian), rift (until Callovian), postrift (until the Upper Cretaceous), and convergence (Neogene). The tectonostratigraphic units were built by 13 sequences of the time scale of second-order sequences. Several of the sequences coincide with discrete subsidence episodes on geohistory plots. For most sequences and sequence boundaries, either a eustatic or a tectonically enhanced origin could be established. A series of seismic facies maps for these sequences visualize the sedimentary basin evolution. Several of the second-order sequences can be subdivided into systems tracts or higher order sequences.

  6. Seismic stratigraphy of the Qiongdongnan deep sea channel system, northwest South China Sea

    NASA Astrophysics Data System (ADS)

    Yuan, Shengqiang; Lü, Fuliang; Wu, Shiguo; Yao, Genshun; Ma, Yubo; Fu, Yanhui

    2009-05-01

    Based on more than 4000 km 2D seismic data and seismic stratigraphic analysis, we discussed the extent and formation mechanism of the Qiongdongnan deep sea channel. The Qiongdongnan deep sea channel is a large incised channel which extends from the east boundary of the Yinggehai Basin, through the whole Qiongdongnan and the Xisha trough, and terminates in the western part of the northwest subbasin of South China Sea. It is more than 570 km long and 4-8 km wide. The chaotic (or continuous) middle (or high) amplitude, middle (or high) continuity seismic facies of the channel reflect the different lithological distribution of the channel. The channel formed as a complex result of global sea level drop during early Pliocene, large scale of sediment supply to the Yinggehai Basin, inversion event of the Red River strike-slip fault, and tilted direction of the Qiongdongnan Basin. The large scale of sediment supply from Red River caused the shelf break of the Yinggehai Basin to move torwards the S and SE direction and developed large scale of prograding wedge from the Miocene, and the inversion of the Red River strike-slip fault induced the sediment slump which formed the Qiongdongnan deep sea channel.

  7. EAST/WEST TRUCK BAY AREA OF TRANSFER BASIN CORRIDOR OF FUEL ...

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

    EAST/WEST TRUCK BAY AREA OF TRANSFER BASIN CORRIDOR OF FUEL STORAGE BUILDING (CPP-603). PHOTO TAKEN LOOKING NORTHWEST. INL PHOTO NUMBER HD-54-19-1. Mike Crane, Photographer, 8/2005 - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

  8. Development of a Willingness to Pay Survey for Willamette Basin Spring Chinook and Winter Steelhead Recovery

    EPA Science Inventory

    Salmon fisheries are a high-profile icon of the Pacific Northwest. Spring Chinook and winter-run steelhead are both listed as federally endangered species in the Willamette basin, the most populated and developed watershed in Oregon. Despite being a high profile issue, there are ...

  9. Stratigraphic analysis of the carboniferous rocks of the Central Appalachian Basin

    SciTech Connect

    Chesnut, D.R. Jr.

    1988-01-01

    A series of seven cross sections was constructed across part of the Central Appalachian Basin in Kentucky, Tennessee, Virginia, West Virginia, and Ohio. Information used to make these sections included well logs, coal-company core descriptions, measured sections, and mapped surface geology. Newly discovered surface and subsurface structural features such as faults, folds, and flexures, are described. A new, unofficial lithostratigraphic nomenclature was introduced to illustrate the stratigraphic framework, and a regional unconformity was interpreted to occur between the Pennsylvanian Pocahontas Formation and the Pennsylvanian New River Formation. The cross sections reveal that sequential truncation of formations below the unconformity occurs t the northwest in the basin. A regional unconformity and biostratigraphic evidence indicate that the Carboniferous rocks were deposited in a series of several small-scale environmental continua. Pennsylvanian rocks overlying the regional unconformity sequentially overlap the underlying rocks to the northwest in the basin. Belts of quartzose sandstones (Lee Formation) within the overlying rocks, are oriented northeast-southwest. Succeeding sandstone belts onlap the unconformity to the northwest within the basin. A fluvial origin is suggested for the quartzose, conglomeratic sands of the Lee Formation. The source for these sands may have been reworked sediments derived from the Old Red Sandstone continent to the northwest in Canada. The remaining Pennsylvanian coal-bearing clastic rocks (Breathitt Group) were deposited as clastic wedges derived from the east and southeast on coastal lowlands.

  10. Washington Phase II Fish Diversion Screen Evaluations in the Yakima River Basin, 1998.

    SciTech Connect

    Blanton, S.L.; McMichael, Geoffrey A.; Neitzel, D.A.

    1999-12-01

    Pacific Northwest National Laboratory (PNNL) evaluated 19 Phase II screen sites in the Yakima River Basin as part of a multi-year study for the Bonneville Power Administration (BPA) on the effectiveness of fish screening devices. The sites were examined to determine if they were being effectively operated and maintained to provide fish a safe, efficient return to the Yakima River.

  11. Salmonid Gamete Preservation in the Snake River Basin, 1998 Annual Report.

    SciTech Connect

    Armstrong, Robyn; Kucera, Paul A.

    1999-03-01

    Steelhead (Oncorhynchus mykiss) and salmon (Oncorhynchus tshawytscha)populations in the Northwest are decreasing. The Nez Perce Tribe (Tribe) was funded in 1998 by the Bonneville Power Administration to coordinate gene banking of male gametes from Endangered Species Act (ESA) listed steelhead and spring and summer chinook salmon in the Snake River basin.

  12. Cross folding in southern Bighorn basin

    SciTech Connect

    Gubbels, T.L.

    1986-08-01

    Analysis of Landsat Thematic Mapper imagery coupled with surface structural investigations of well-exposed folds in the southern Bighorn basin have revealed two northwest-trending folds that have been refolded. The eastern boundary of the Owl Creek Mountains is characterized by a well-defined alignment of folds that extend north-northwest from the Owl Creek thrust front. Bridger monocline, Wildhorse Butte anticline, and Red Hole anticline lie along this trend. Initial Laramide folding, probably during latest Cretaceous time, resulted in a single, continuous, north-northwest-trending anticline with a southwestward vergence. This anticline was progressively unfolded from south to north as the Owl Creek Range was thrust southward over the Wind River basin in earliest Eocene time; scissors-like vertical motion along this flexure rotated the axial surface of the early formed Bridger anticline, resulting in a monocline with a reversed vergence (northeastward). Formation of the Thermopolis/East Warm Springs anticline parallel to the north flank of the range accompanied thrusting and effectively refolded the northern end of the Wildhorse Butte anticline along an east-west axis. Faulting of the oversteepened south limb of the Red Hole cross fold was contemporaneous with folding. Cross-cutting fold axes in this area and the Mud Creek area to the west are best explained by a counterclockwise change in stress direction during the latest phase of the Laramide orogeny. Vertical movement along the eastern side of the Owl Creek Range results from differential motion in the hanging wall of the crystalline thrust sheet.

  13. Amplification of seismic waves by the Seattle basin, Washington State

    USGS Publications Warehouse

    Pratt, T.L.; Brocher, T.M.; Weaver, C.S.; Creager, K.C.; Snelson, C.M.; Crosson, R.S.; Miller, K.C.; Trehu, A.M.

    2003-01-01

    Recordings of the 1999 Mw 7.6 Chi-Chi (Taiwan) earthquake, two local earthquakes, and five blasts show seismic-wave amplification over a large sedimentary basin in the U.S. Pacific Northwest. For weak ground motions from the Chi-Chi earthquake, the Seattle basin amplified 0.2- to 0.8-Hz waves by factors of 8 to 16 relative to bedrock sites west of the basin. The amplification and peak frequency change during the Chi-Chi coda: the initial S-wave arrivals (0-30 sec) had maximum amplifications of 12 at 0.5-0.8 Hz, whereas later arrivals (35-65 sec) reached amplifications of 16 at 0.3-0.5 Hz. Analysis of local events in the 1.0- to 10.0-Hz frequency range show fourfold amplifications for 1.0-Hz weak ground motion over the Seattle basin. Amplifications decrease as frequencies increase above 1.0 Hz, with frequencies above 7 Hz showing lower amplitudes over the basin than at bedrock sites. Modeling shows that resonance in low-impedance deposits forming the upper 550 m of the basin beneath our profile could cause most of the observed amplification, and the larger amplification at later arrival times suggests surface waves also play a substantial role. These results emphasize the importance of shallow deposits in determining ground motions over large basins.

  14. Promise seen in Petrel sub-basin off northwestern Australia

    SciTech Connect

    Maung, T.U.; Passmore, V. )

    1995-01-30

    The Australian government during the past 11 years has been regularly releasing vacant areas on the Australian continental shelf for exploration. Although Australia's offshore basins cover an area of 12 million sq km, only about 1,100 exploration and development wells have been drilled, and most of the basins are underexplored by world standards. One of these areas is the Petrel sub-basin of the Bonaparte basin in water shallower than 100 m off Northwest Australia. The government recently released six areas in the southern offshore Petrel subbasin for petroleum exploration. The results of a study by the Petroleum Resources Branch of the bureau of Resource Sciences have been synthesized into a Petrel Sub-basin Bulletin, some selections of which are discussed in this article. Although there are over 44,000 km of seismic data recorded in the sub-basin, the quality of pre-1979 data is very poor to poor, and only 15,800 km of data recorded between 1980--94 (including 1,000 km of 3D seismic data over the Barnett structure) are of fair to good quality. The paper describes the regional geology, reservoir and seals, source rocks, and types of geologic traps. The study identified over 30 structures and leads in the offshore southern Petrel sub-basin. Significant opportunities exist for delineation and definition of drillable prospects in this promising Australian petroleum province.

  15. Source rocks of the Sub-Andean basins

    SciTech Connect

    Raedeke, L.D. )

    1993-02-01

    Seven source rock systems were mapped using a consistent methodology to allow basin comparison from Trinidad to southern Chile. Silurian and Devonian systems, deposited in passive margin and intracratonic settings, have fair-good original oil/gas potential from central and northern Bolivia to southern Peru. Kerogens range from mature in the foreland to overmature in the thrust belt. Permian to Carboniferous deposition in local restricted basins formed organic-rich shales and carbonates with very good original oil/gas potential, principally in northern Bolivia and southern Peru. Late Triassic to early Jurassic marine shales and limestones, deposited in deep, narrow, basins from Ecuador to north-central maturity. Locally, in the Cuyo rift basin of northern Argentina, a Triassic lacustrine unit is a very good, mature oil source. Early Cretaceous to Jurassic marine incursions into the back-arc basins of Chile-Argentina deposited shales and limestones. Although time transgressive (younging to the south), this system is the principal source in southern back-arc basins, with best potential in Neuquen, where three intervals are stacked A late Cretaceous marine transgressive shale is the most important source in northern South America. The unit includes the La Luna and equivalents extending from Trinidad through Venezuela, Colombia, Ecuador, and into northern Peru. Elsewhere in South America upper Cretaceous marine-lacustrine rocks are a possible source in the Altiplano and Northwest basins of Bolivia and Argentina. Middle Miocene to Oligocene source system includes shallow marine, deltaic, and lacustrine sediments from Trinidad to northern Peru.

  16. Sedimentary sequence evolution in a Foredeep basin: Eastern Venezuela

    SciTech Connect

    Bejarano, C.; Funes, D.; Sarzalho, S.; Audemard, F.; Flores, G.

    1996-08-01

    Well log-seismic sequence stratigraphy analysis in the Eastern Venezuela Foreland Basin leads to study of the evolution of sedimentary sequences onto the Cretaceous-Paleocene passive margin. This basin comprises two different foredeep sub-basins: The Guarico subbasin to the west, older, and the Maturin sub-basin to the east, younger. A foredeep switching between these two sub-basins is observed at 12.5 m.y. Seismic interpretation and well log sections across the study area show sedimentary sequences with transgressive sands and coastal onlaps to the east-southeast for the Guarico sub-basin, as well as truncations below the switching sequence (12.5 m.y.), and the Maturin sub-basin shows apparent coastal onlaps to the west-northwest, as well as a marine onlap (deeper water) in the west, where it starts to establish. Sequence stratigraphy analysis of these sequences with well logs allowed the study of the evolution of stratigraphic section from Paleocene to middle Miocene (68.0-12.0 m.y.). On the basis of well log patterns, the sequences were divided in regressive-transgressive-regressive sedimentary cycles caused by changes in relative sea level. Facies distributions were analyzed and the sequences were divided into simple sequences or sub- sequences of a greater frequencies than third order depositional sequences.

  17. Structure and geologic history of late Cenozoic Eel River basin, California

    SciTech Connect

    Clarke, S.H. Jr.

    1988-03-01

    The Eel River basin formed as a late Cenozoic forearc basin floored by late Mesozoic and early Cenozoic allochthonous terranes (central and coastal belts of the Franciscan complex). Regionally, basement rocks are unconformably overlain on land by a sedimentary sequence as much as about 4200 m thick that comprises the Bear River Formation (early and middle Miocene) and the Wildcat Group (late Miocene to middle Pleistocene) and offshore by broadly coeval upper Tertiary and Quaternary deposits as much as 3300 m thick. Offshore, the southern part of the basin is typified by the seaward extensions of youthful northeast-dipping thrust and reverse faults and northwest-trending anticlines. The latest period of deformation in this part of the basin began during the middle Pleistocene and probably reflects north-northwestward migration of the Mendocino triple junction and encroachment of the Pacific plate. Farther north, the western basin margin and adjacent upper continental slope are separated from the axial part of the offshore basin by a narrow zone of north-northwest-trending, right-stepping en echelon folds. These folds indicate that northeast-southwest compression characteristic of the southern part of the basin is accompanied toward the north by right-lateral shear between the accretionary complex to the west and the basin to the east. The northeastern margin of the offshore basin is cut by north to north-northwest-trending high-angle reverse faults that vertically offset basement rocks as much as 1300 m, west side down. These faults, which may merge northward, coincide with older terrane boundaries and locally show evidence of late Cenozoic reactivation with possible right-lateral slip.

  18. Crustal rifting and subsidence of Sirte basin, Libya: a mature hydrocarbon Province

    SciTech Connect

    Gumati, Y.; Schamel, S.; Nairn, A.E.M.

    1985-02-01

    The complex rifting and subsidence history of the Sirte basin serves as an instructive case study of the tectonic evolution of an intercratonic extensional basin. The Sirte basin formed by collapse of the Sirte arch in the mid-Cretaceous. Marine sediments accumulated following initial crustal arching and rifting as the basin was flooded from the north. Upper Cretaceous strata lie unconformably on igneous and metamorphic rocks of the Precambrian basement complex, Cambrian-Ordovician Gargaf Group, or the pre-Cretaceous continental Nubian Sandstone. The most rapid subsidence and accumulation of basinal strata occurred in the early Cenozoic; however, the basin has been relatively stable since the Oligocene. The basin is floored by a northwest-southeast-trending mosaic of narrow horsts and grabens, an important structural characteristic that distinguishes it from the adjacent intracratonic Kufra, Murzuk, and Ghadames basins. The details of basin subsidence, sediment accumulation rates, and facies variations have been reconstructed for the northern Sirte basin from a suite of approximately 100 well logs and numerous seismic lines. Subsidence-rate maps for short time intervals from the mid-Cretaceous through the Eocene show a continual shifting of the loci of maximum and minimum subsidence. The nonsteady character of basin subsidence may reflect a periodicity of movement on the major basement-rooted growth faults bounding the underlying horsts and grabens.

  19. Statistical Comparisons of watershed scale response to climate change in selected basins across the United States

    USGS Publications Warehouse

    Risley, John; Moradkhani, Hamid; Hay, Lauren; Markstrom, Steve

    2011-01-01

    In an earlier global climate-change study, air temperature and precipitation data for the entire twenty-first century simulated from five general circulation models were used as input to precalibrated watershed models for 14 selected basins across the United States. Simulated daily streamflow and energy output from the watershed models were used to compute a range of statistics. With a side-by-side comparison of the statistical analyses for the 14 basins, regional climatic and hydrologic trends over the twenty-first century could be qualitatively identified. Low-flow statistics (95% exceedance, 7-day mean annual minimum, and summer mean monthly streamflow) decreased for almost all basins. Annual maximum daily streamflow also decreased in all the basins, except for all four basins in California and the Pacific Northwest. An analysis of the supply of available energy and water for the basins indicated that ratios of evaporation to precipitation and potential evapotranspiration to precipitation for most of the basins will increase. Probability density functions (PDFs) were developed to assess the uncertainty and multimodality in the impact of climate change on mean annual streamflow variability. Kolmogorov?Smirnov tests showed significant differences between the beginning and ending twenty-first-century PDFs for most of the basins, with the exception of four basins that are located in the western United States. Almost none of the basin PDFs were normally distributed, and two basins in the upper Midwest had PDFs that were extremely dispersed and skewed.

  20. Pacific Northwest Storms Situation Report # 1

    SciTech Connect

    2006-12-15

    Severe wind and snow storms hit the Pacific Northwest region on December 14 – 15, 2006, following severe flooding during the past few days. The severe weather resulted in major power outages through the region. At peak there were 1.8 million customers without power which included BC Hydro in Canada. Currently, there are over 1.5 million outages in the region as a result of the Pacific Northwest Storms. This represents about 42 percent of customers in affected utility service areas in Oregon and Washington. See table below. Because the current wind and snow storms are coming on the heels of extensive flooding in the region, electric utilities are experiencing damage. Wind gusts reached close to 100 mph in some areas of the region. The storm is expected to bring its strong winds and heavy snow into Idaho, Montana and Wyoming Friday and into the weekend. There are currently no reported major impacts to the petroleum and natural gas infrastructure.

  1. Three-Dimensional Geologic Characterization of a Great Basin Geothermal System: Astor Pass, Nevada

    SciTech Connect

    Mayhew, Brett; Siler, Drew L; Faulds, James E

    2013-09-30

    The Great Basin, western USA, exhibits anomalously high heat flow (~75±5 mWm-2) and active faulting and extension, resulting in ~430 known geothermal systems. Recent studies have shown that steeply dipping normal faults in transtensional pull-aparts are a common structural control of these Great Basin geothermal systems. The Astor Pass blind (no surface expression) geothermal system, Nevada, lies along the boundary between the Basin and Range to the east and the Walker Lane to the west. Across this boundary, strain is transferred from dextral shear in the Walker Lane to west-northwest directed extension in the Basin and Range, resulting in a transtensional setting consisting of both northwest-striking, left-stepping dextral faults and northerly striking normal faults. Previous studies indicate that Astor Pass was controlled by the intersection of a northwest-striking dextral normal fault and north-northwest striking normal-dextral fault bounding the western side of the Terraced Hills. Drilling (to ~1200 m) has revealed fluid temperatures of ~94°C, confirming a blind geothermal system. Expanding upon previous work and employing interpretation of 2D seismic reflection data, additional detailed geologic mapping, and well cuttings analysis, a 3-dimensional geologic model of the Astor Pass geothermal system was constructed. The 3D model indicates a complex interaction/intersection area of three discrete fault zones: a northwest-striking dextral-normal fault, a north-northwest-striking normal-dextral fault, and a north-striking west-dipping normal fault. These two discrete, critically-stressed intersection areas plunge moderately to steeply to the NW-NNW and probably act as conduits for upwelling geothermal fluids.

  2. Glacial-to-Holocene evolution of sea surface temperature and surface circulation in the subarctic northwest Pacific and the Western Bering Sea

    NASA Astrophysics Data System (ADS)

    Meyer, Vera D.; Max, Lars; Hefter, Jens; Tiedemann, Ralf; Mollenhauer, Gesine

    2016-07-01

    It has been proposed that North Pacific sea surface temperature (SST) evolution was intimately linked to North Atlantic climate oscillations during the last glacial-interglacial transition. However, during the early deglaciation and the Last Glacial Maximum, the SST development in the subarctic northwest Pacific and the Bering Sea is poorly constrained as most existing deglacial SST records are based on alkenone paleothermometry, which is limited prior to 15 ka B.P. in the subarctic North Pacific realm. By applying the TEXL86 temperature proxy we obtain glacial-Holocene-SST records for the marginal northwest Pacific and the Western Bering Sea. Our TEXL86-based records and existing alkenone data suggest that during the past 15.5 ka, SSTs in the northwest Pacific and the Western Bering Sea closely followed millennial-scale climate fluctuations known from Greenland ice cores, indicating rapid atmospheric teleconnections with abrupt climate changes in the North Atlantic. Our SST reconstructions indicate that in the Western Bering Sea SSTs drop significantly during Heinrich Stadial 1 (HS1), similar to the known North Atlantic climate history. In contrast, progressively rising SST in the northwest Pacific is different to the North Atlantic climate development during HS1. Similarities between the northwest Pacific SST and climate records from the Gulf of Alaska point to a stronger influence of Alaskan Stream waters connecting the eastern and western basin of the North Pacific during this time. During the Holocene, dissimilar climate trends point to reduced influence of the Alaskan Stream in the northwest Pacific.

  3. Pacific Northwest Storms Situation Report # 5

    SciTech Connect

    2006-12-19

    Significant progress has been made in restoring power to customers in the Pacific Northwest region. Currently, 186,627 customers remain without power. The majority of customers without power are served by Puget Sound Energy. This is down from 1.8 million customers who lost power following severe wind and snow storms on December 14-15, 2006. The customers without power represent about 6 percent of customers in the affected utility service areas of Oregon and Washington. See table below.

  4. Site Testing in the Northwest of Argentina

    NASA Astrophysics Data System (ADS)

    Recabarren, P.; García Lambas, D.; Muriel, H.; Stasyszyn, F.; Renzi, V.; Vrech, R.; Viramonte, J.; Sarazin, M.

    2009-05-01

    We present results of the characterization of the Tolar Grande-Macon Range site in the North-West of Argentina. This project is being developed by the IATE in collaboration with ESO in the framework of the E-ELT project. We present and discuss one year of image quality measurements with MASS and DIMM, three years of meteorological data and detailed studies of seismic activity and geo-technical aspects as well as diverse logistic issues.

  5. Andes Altiplano, Northwest Argentina, South America

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This view of the Andes Altiplano in northwest Argentina (25.5S, 68.0W) is dominated by heavily eroded older and inactive volcano peaks. The altiplano is a high altitude cold desert like the Tibetan Plateau but smaller in area. It is an inland extension of the hyperarid Atacama Desert of the west coast of South America and includes hundreds of volcanic edifices (peaks, cinder cones, lava flows, debris fields, lakes and dry lake beds (salars).

  6. Sustaining the Northwest Way of Life.

    SciTech Connect

    United States. Bonneville Power Administration. Customer Services.

    1991-08-01

    These Discussion Papers are from a number of organizations with a high stake in the future performance of the Bonneville Power Administration. Bonneville solicited papers from other organizations to assure a broaded-based discussion of the topics for the 1991 Programs in Perspective. PIP meetings will be held throughout the Northwest in September. PIP runs on a two-year cycle. The first year is aimed at discussion of broad, strategic issues. The second year evaluates specific program levels for all Bonneville programs and test them for affordability against financial constraints. This year's PIP focuses on strategic-issues discussion. It specifically asks for regional discussion to help put some flesh on the skeleton of Bonneville's own vision for its future: Best for the Northwest Through Teamwork B... P... A... The Most Competitive and Socially Responsible Power System in the Nation'' Specific topics are (1) achieving social responsibility and (2) conserving Northwest competitiveness. Bonneville executives chose this vision as a means of directing the organization into and beyond the 1990s. It guides the 3000 plus employees of the agency in their day-to-day operations. By asking for discussion of the terms Most Competitive'' and Socially Responsible'' in the 1991 PIP, Bonneville intends to better understand the diverse needs of its customers and constituents, and to become of even greater service to the Northwest. The papers are designed to help stimulate thought about the dimensions of the future direction of BPA. Bonneville intends that the real substance of PIP will occur in the meetings themselves. We hope that these papers will provoke new thinking, and that the interchange of views in the meetings will produce new approaches to the issues.

  7. Serving the People of the Northwest

    SciTech Connect

    None, None

    2009-05-01

    IF YOU LIVE IN THE PACIFIC NORTHWEST, CHANCES ARE YOU USE ELECTRICITY THAT’S MARKETED BY THE BONNEVILLE POWER ADMINISTRATION OR IS TRANSMITTED OVER BPA POWER LINES. Headquartered in Portland, Ore., BPA is a federal agency that markets wholesale electricity and transmission to the region’s utilities as well as to some large industries. BPA provides about one-third of the electricity used in the Northwest and operates over three-fourths of the region’s high-voltage transmission. BPA does not rely on annual appropriations from Congress for its financing. Instead, the agency recovers all of its costs through sales of electricity and transmission services and repays the U.S. Treasury in full with interest for any money it borrows. BPA sells wholesale power at cost rather than charging market prices. The bulk of the power BPA sells is generated at federal hydroelectric dams on the Columbia River, thus providing some of the lowest-cost electricity in the nation. This low-cost, clean power has been a cornerstone of the Northwest economy for decades, stimulating growth and new jobs. As concerns about global climate change are placing a new premium on clean energy, the federal hydro system has become an increasingly valuable resource. In addition to being low cost, electricity produced by the federal hydro system has no greenhouse gas emissions. And this power source is renewable — replenished each year by the region’s rainfall and snowmelt.

  8. Gravity anomalies and the structure of western Tibet and the southern Tarim Basin

    NASA Technical Reports Server (NTRS)

    Lyon-Caen, H.; Molnar, P.

    1984-01-01

    Gravity anomalies across the western part of the Tarim Basin and the Kunlun mountain belt show that this area is not in local isostatic equilibrium. These data can be explained if a strong plate underlying the Tarim Basin extends southwestward beneath the belt at least 80 km and supports part of the topography of northwest Tibet. This corroborates Norin's inference that late Tertiary crustal shortening has occurred in this area by southward underthrusting of the Tarim Basin beneath the Kunlun. This study places a lower bound on the amount of underthrusting.

  9. Northwest Climate Science Center: Integrating Regional Research, Conservation and Natural Resource Management

    NASA Astrophysics Data System (ADS)

    Mote, P.; Bisbal, G.

    2012-12-01

    The Northwest Climate Science Center (NW CSC) was established in 2010, among the first three of eight regional Climate Science Centers created by the Department of the Interior (DOI). The NW CSC is supported by an academic consortium (Oregon State University, University of Idaho, and the University of Washington), which has the capacity to generate and coordinate decision-relevant science related to climate, thus serving stakeholders across the Pacific Northwest region. The NW CSC has overlapping boundaries with three Landscape Conservation Cooperatives (LCCs): the Great Northern, the Great Basin, and the North Pacific. Collaboration between the NW CSC and these three LCCs addresses the highest priority regional climate science needs of Northwest natural and cultural resource managers. Early in 2012, the NW CSC released its first Strategic Plan for the period 2012-2015. The plan offers a practical blueprint for operation and describes five core services that the NW CSC provides to the Northwest community. These core services emphasize (a) bringing together the regional resource management and science communities to calibrate priorities and ensure efficient integration of climate science resources and tools when addressing practical issues of regional significance; (b) developing and implementing a stakeholder-driven science agenda which highlights the NW CSC's regional leadership in generating scenarios of the future environment of the NW; (c) supporting and training graduate students at the three consortium universities, including through an annual 'Climate science boot camp'; (d) providing a platform for effective climate-change-related communication among scientists, resource managers, and the general public; and (e) national leadership in data management and climate scenario development.

  10. What is a population? Spouse import in the northwest Amazon.

    PubMed

    Chernela, J M

    1994-03-01

    In northwest Amazon societies, diverse groups marry across linguistic and geographic barriers: kinship and kin proximity occur according to cultural rules, and kinship, language, and residence may not be equated with genetic relatedness, as previously postulated. The assumption of genetic relatedness and random mating within a prescribed geographic zone or linguistic unit does not always hold true. Models should be based on cultural determinants of population dynamics that are more sensitive to detailed mate choice and gene flow patterns. The example is given of the Wanano, who belong to the Eastern Tukanoan Language group in the Central Northwest Amazon basin of the Uaupes River; 500-600 lived in Brazil, 180 Colombia, and 800 in the Vaupes Territory of Colombia. Settlements were 3-24 km from the river and had a population of 17-160 people. Men pursued fishing and women engaged in manioc cultivation. There was minimal exploitation of resources. The Wanano are unilineal kin groups with cross cousin marriages. They share a common cultural heritage with 15-20 other kin groups, and are linked through intermarriage. 14,000 Indians of diverse languages are thus united in marriage and kinship. Neighboring Arawakan and Cariban speaking groups reside to the north and west. About 13 distinct languages are part of the Eastern Tukanoan language. The basic principles of descent, marriage, and residence were supplied, and the consequences for village composition explicated. Focus was placed on 3 Wanano villages (Yapima; Mo, a large village with in-marrying from the village of Buhpoara; and Buhpoara) and spouse importation. Social organization was on the basis of sib (patrilineal descent group), language group (common identity, language, ancestry, and group name), and phratry, or nonresidential association of language groups. Ties were strong among more intimate or a"in-groups." Marriage rules applied to preferences for patrilineal cross cousins and sister exchange. The villages

  11. Reserves in Western Basins

    SciTech Connect

    Caldwell, R.H.; Cotton, B.W.

    1993-12-31

    The objective of this project is to investigate the reserves potential of overpressured tight (OPT) gas reservoirs in three Rocky Mountain basins. These are the Greater Green River Basin (GGRB), Uinta Basin and Piceance Basin. By documenting productive characteristics in these basins and characterizing the nature of the vast gas resources in place, the reserves potential may be understood and quantified. Through this understanding, it is hoped that the oil and gas industry will be encouraged to pursue exploitation of this resource. At this point in time, the GGRB work has been completed and the final report submitted for publication. Work on the Uinta basin has just commenced and work on the Piceance basin will commence next year. Since the GGRB portion of this project has been completed, further discussion centers upon this Basin.

  12. Gravity, magnetic, and physical property data in the Smoke Creek Desert area, northwest Nevada

    USGS Publications Warehouse

    Tilden, Janet E.; Ponce, David A.; Glen, Jonathan M.G.; Chuchel, Bruce A.; Tushman, Kira; Duvall, Alison

    2006-01-01

    The Smoke Creek Desert, located approximately 100 km (60 mi) north of Reno near the California-Nevada border, is a large basin situated along the northernmost parts of the Walker Lane Belt (Stewart, 1988), a physiographic province defined by northwest-striking topographic features and strike-slip faulting. Because geologic framework studies play an important role in understanding the hydrology of the Smoke Creek Desert, a geologic and geophysical effort was begun to help determine basin geometry, infer structural features, and estimate depth to Pre-Cenozoic rocks, or basement. In May and June of 2004, and June of 2005, the U.S. Geological Survey (USGS) collected 587 new gravity stations, more than 160 line-kilometers (100 line-miles) of truck-towed magnetometer data, and 111 rock property samples in the Smoke Creek Desert and vicinity in northwest Nevada, as part of an effort to characterize its hydrogeologic framework. In the Smoke Creek Desert area, gravity highs occur over rocks of the Skedaddle Mountains, Fox Range, Granite Range, and over portions of Tertiary volcanic rocks in the Buffalo Hills. These gravity highs likely reflect basement rocks, either exposed at the surface or buried at shallow depths. The southern Smoke Creek Desert corresponds to a 25-mGal isostatic gravity low, which corresponds with a basin depth of approximately 2 km. Magnetic highs are likely due to granitic, andesitic, and metavolcanic rocks, whereas magnetic lows are probably associated with less magnetic gneiss and metasedimentary rocks in the region. Three distinctive patterns of magnetic anomalies occur throughout the Smoke Creek Desert and Squaw Creek Valley, likely reflecting three different geological and structural settings.

  13. Effects of Climate Change on Flood Frequency in the Pacific Northwest

    NASA Astrophysics Data System (ADS)

    Gergel, D. R.; Stumbaugh, M. R.; Lee, S. Y.; Nijssen, B.; Lettenmaier, D. P.

    2014-12-01

    A key concern about climate change as related to water resources is the potential for changes in hydrologic extremes, including flooding. We explore changes in flood frequency in the Pacific Northwest using downscaled output from ten Global Climate Models (GCMs) from the Coupled Model Inter-Comparison Project 5 (CMIP5) for historical forcings (1950-2005) and future Representative Concentration Pathways (RCPs) 4.5 and 8.5 (2006-2100). We use archived output from the Integrated Scenarios Project (ISP) (http://maca.northwestknowledge.net/), which uses the Multivariate Adaptive Constructed Analogs (MACA) method for statistical downscaling. The MACA-downscaled GCM output was then used to force the Variable Infiltration Capacity (VIC) hydrology model with a 1/16th degree spatial resolution and a daily time step. For each of the 238 HUC-08 areas within the Pacific Northwest (USGS Hydrologic Region 15), we computed, from the ISP archive, the series of maximum daily runoff values (surrogate for the annual maximum flood), and then the mean annual flood. Finally, we computed the ratios of the RCP4.5 and RCP8.5 mean annual floods to their corresponding values for the historical period. We evaluate spatial patterns in the results. For snow-dominated watersheds, the changes are dominated by reductions in flood frequency in basins that currently have spring-dominant floods, and increases in snow affected basins with fall-dominant floods. In low elevation basins west of the Cascades, changes in flooding are more directly related to changes in precipitation extremes. We further explore the nature of these effects by evaluating the mean Julian day of the annual maximum flood for each HUC-08 and how this changes between the historical and RCP4.5 and RCP8.5 scenarios.

  14. Megafans of the Northern Kalahari Basin

    NASA Technical Reports Server (NTRS)

    Wilkinson, M. J.; Miller, R. McG.; Eckardt, F.; Kreslavsky, M. A.

    2016-01-01

    We identify eleven megafans (partial cones of fluvial sediment, >80 km radius) in the northern Kalahari Basin, using several criteria based on VIS and IR remotely sensed data and SRTM-based surface morphology reconstructions. Two other features meet fewer criteria of the form which we class as possible megafans. The northern Kalahari megafans are located in a 1700 km arc around the southern and eastern flanks of the Angola's Bié Plateau, from northern Namibia through northwest Botswana to western Zambia. Three lie in the Owambo subbasin centered on the Etosha Pan, three in the relatively small Okavango rift depression, and five in the Upper Zambezi basin. The population includes the well-known Okavango megafan (150 km), Namibia's Cubango megafan, the largest megafan in the region (350 km long), and the largest nested group (the five major contiguous megafans on the west slopes of the upper Zambezi Valley). We use new, SRTM-based topographic roughness data to discriminate various depositional surfaces within the flat N. Kalahari landscapes. We introduce the concepts of divide megafans, derived megafans, and fan-margin rivers. Conclusions. (i) Eleven megafan cones total an area of 190,000 sq km. (ii) Different controls on megafan size operate in the three component basins: in the Okavango rift structural controls become the prime constraint on megafan length by controlling basin dimensions. Megafans in the other les constricted basins appear to conform to classic relationships fan area, slope, and feeder-basin area. (iii) Active fans occupy the Okavango rift depression with one in the Owambo basin. The rest of the population are relict but recently active fans (surfaces are relict with respect to activity by the feeder river). (iv) Avulsive behavior of the formative river-axiomatic for the evolution of megafans-has resulted in repeated rearrangements of regional drainage, with likely effects in the study area well back into the Neogene. Divide megafans comprise the

  15. Comparative Study on the Electrical Properties of the Oceanic Mantle Beneath the Northwest Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Toh, H.

    2013-12-01

    We have been conducting long-term seafloor electromagnetic (EM) observations at two sites in the northwest Pacific since 2001. The older site was established at the deep seafloor (~5600m) on the northwest Pacific basin (Site NWP), while the new one was installed on the west Philippine basin (Site WPB) in 2006 at the slightly deeper (~5700m) seafloor. The ages of the oceanic basins at those sites are approximately 129 Ma for Site NWP (Shipboard Scientific Party of ODP Leg 191, 2000) and 49 Ma for Site WPB (Salisbury et al., 2006), respectively. The EM instruments deployed at those sites are seafloor EM stations (SFEMS; Toh et al., 2004 and 2006) and capable of measuring vector EM fields at the seafloor for as long as one year or more with other physical quantities such as the instruments' attitude, orientation and temperature. One of the objectives of the seafloor long-term EM observations by SFEMSs is to make a comparative study of the oceanic mantle with and without influence of the so-called 'stagnant slabs' in terms of their electrical conductivity. It is anticipated that the mantle transition zone under the influence of the stagnant slab has a higher electrical conductivity because the transition zone there could be wetter than that in the absence of the stagnant slab. In this context, the mantle transition zone beneath Site WPB can be said to have influence by the stagnant slab, while that beneath Site NWP does not. It, therefore, is basically possible to estimate how much water is present in each transition zone by comparison of the electrical conductivity profiles of the two. The one-dimensional electrical profile beneath Site NWP has been derived so far using the magnetotelluric (MT) and geomagnetic depth sounding (GDS) methods with significant jumps in the electrical property at 410 and 660km discontinuities. The jumps are approximately factors of 10 and 2, respectively (Ichiki et al., 2009). Here we show a profile beneath Site WPB using both MT and GDS

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

    SciTech Connect

    Schlische, R.W. ); Olsen, P.E. )

    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.

  17. First dedicated hydrographic survey of the Comoros Basin

    NASA Astrophysics Data System (ADS)

    Collins, C.; Hermes, J. C.; Roman, R. E.; Reason, C. J. C.

    2016-02-01

    The Comoros Basin, a region of eddies that propagate into the Mozambique Channel and subsequently the Agulhas Current, has not been well studied. This paper presents the findings from the first dedicated research cruise in the basin. ADCP data collected during the cruise show that the circulation in the Comoros Basin is dominated by the strong westward flowing North East Madagascar Current, which bifurcates twice: once upon encountering the Davie Ridge and again upon reaching the East African coast. One of the branches flows southward along the African coastline and appears to continue into the Mozambique Channel while the other branch turns northward to become the East African Coastal Current. The ADCP data also show evidence of a cyclonic eddy along the northwest coast of Madagascar. Water mass analysis indicates that all the major Indian Ocean water masses are present in the Comoros Basin. Surprisingly, North Atlantic Deep Water, a water mass previously assumed to only occur south of ˜16°S in the Mozambique Channel, was found to be present in the basin at depths below 2000 m. Antarctic Intermediate Water is found to enter the basin via two routes; from the west within the North East Madagascar Current and from the south within the northward flowing Mozambique Undercurrent.

  18. California Basin Studies (CaBS). Final contract report

    SciTech Connect

    Gorsline, D.S.

    1991-12-31

    The California Continental Borderland`s present configuration dates from about 4 to 5 X 10{sup 6} years Before Present (B.P.) and is the most recent of several configurations of the southern California margin that have evolved after the North America Plate over-rode the East Pacific Rise about 30 X 10{sup 6} years ago. The present morphology is a series of two to three northwest-southeast trending rows of depressions separated by banks and insular ridges. Two inner basins, Santa Monica and San Pedro, have been the site for the Department of Energy-funded California Basin Study (CaBS) Santa Monica and San Pedro Basins contain post-Miocene sediment thicknesses of about 2.5 and 1.5 km respectively. During the Holocene (past 10,000 years) about 10-12 m have accumulated. The sediment entered the basin by one or a combination of processes including particle infall (mainly as bioaggregates) from surface waters, from nepheloid plumes (surface, mid-depths and near-bottom), from turbidity currents, mass movements, and to a very minor degree direct precipitation. In Santa Monica Basin, during the last century, particle infall and nepheloid plume transport have been the most common processes. The former dominates in the central basin floor in water depths from 900 to 945 m. where a characteristic silt-clay with a typical mean diameter of about 0.006 mm, phi standard deviation.

  19. Tectonostratigraphic evolution of the Williston Basin

    NASA Astrophysics Data System (ADS)

    Redly, Pal

    In the Williston Basin five regional seismic profiles, covering ˜3090 km were utilized for a comprehensive study of this complex geologic feature. 2300 km field data were added to the existing 790 km profile. The novel seismic information in conjunction with a sizeable number of wireline data and incorporation of structural and isopach maps provided a unique data environment for development of a new elaborate tectonostratigraphic model of this major continental depression. Standard reflection seismic processing procedures were implemented with special emphasis on regional perspectives, including "Earth curvature correction", to generate images of the basin fill. The latter helped to reveal the true nature of this large scale cratonic basin. This novel information permitted new approaches in establishing the deformation styles in the Williston Basin. Structural studies of the newly reprocessed regional seismic profiles revealed the compressional nature of the radially arranged tectonic elements in the center of the basin, and the extensional character of the peripheral regions. The results suggest that axisymmetric deformation controlled the early stages of the Williston Basin area, and was the causal factor of the oval shape of the basin. In the first, "pre-Williston" phase, the region was uplifted by an axisymmetric lithospheric intrusion creating radial extensional signatures in the central zone and compressional structures in the surroundings. Erosion and thermal cooling and/or phase change of the mantle material led to the initiation of the basin subsidence. Consequently, in the "intracratonic phase" (Sauk - Absaroka), the pre-existing radial and circumferentially arranged structures were periodically reactivated in the opposite sense. The active periods were unrelated to global orogenic events of the continent. The exception is the Kaskaskia I (Devonian) interval, when the territory was tilted to the northwest and the axisymmetric cause of the subsidence was

  20. Technology transfer at Pacific Northwest Laboratory

    SciTech Connect

    Not Available

    1988-08-01

    Pacific Northwest Laboratory (PNL) manages an aggressive technology transfer program for the US Department of Energy (DOE) to help US industry implement the results of federally developed technologies. A benefit of this program is that PNL increases the use of results from its research programs and assists industries in solving technical problems, enhancing their productivity and international competitiveness. The technology transfer program began at PNL in 1981 with one person. Since then, it has evolved into an innovative organization that manages the deployment of technologies developed by the Laboratory's research and engineering centers. Technology transfer is a vital mission of the Laboratory.

  1. Pacific Northwest Storms Situation Report # 6

    SciTech Connect

    2006-12-20

    Significant progress has been made in restoring power to customers in the Pacific Northwest region. Currently, 134,868 customers remain without power. The number of outages is down from 1.8 million customers who lost power following severe wind and snow storms on December 14-15, 2006. The customers without power represent less than 5 percent of customers in the affected utility service areas of Oregon and Washington. The majority of customers without power are served by Puget Sound Energy and Seattle City Light.

  2. Pacific Northwest Storms Situation Report # 3

    SciTech Connect

    2006-12-17

    Significant progress has been made in restoring power to customers in the Pacific Northwest region. Currently, 468,200 customers, including Canada, remain without power. This is down from 1.8 million customers who lost power following severe wind and snow storms on December 14-15, 2006. The customers without power represent about 16 percent of customers in the affected utility service areas of Oregon and Washington. See table below. The Olympic pipeline reports that the pipeline is operational; however, pipeline throughput remains reduced since one substation along the line remains without power. Complete power restoration is expected later today. There are no reports of problems regarding fuel distribution and production.

  3. Color view to Northwest of Phoenix

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This approximate color (SSI's red, green, and blue filters: 600, 530, and 480 nanometers) view was obtained on sol 2 by the Surface Stereo Imager (SSI) on board the Phoenix lander. The view is toward the northwest, showing polygonal terrain near the lander and out to the horizon.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. Seasonal and successional streamflow response to forest cutting and regrowth in the northwest and eastern United States

    NASA Astrophysics Data System (ADS)

    Jones, Julia A.; Post, David A.

    2004-05-01

    This study examined daily streamflow response over up to four decades in northwest conifer forest and eastern deciduous forest sites in the United States. We used novel methods to analyze daily observations of climate and streamflow spanning more than 900 basin years of record at 14 treated/control basin pairs where forest removal and regrowth experiments were underway in the period 1930-2002. In the 1 to 5-year period after forest removal, maximum daily increases ranged from 2 to 3 mm at deciduous forest sites, to 6 to 8 mm at conifer forest sites. Significant spring surpluses persisted for up to 35 years in conifer forest basins, but winter and spring streamflow deficits appeared after 10 to 15 years of forest regrowth in eastern deciduous forest basins. In all 5-yr posttreatment periods, absolute changes in daily streamflow were significantly more likely during moist, warm seasons, or during snowmelt seasons, but relative changes were more likely during warm seasons irrespective of moisture status. Both relative and absolute streamflow changes in the 1 to 5 and 15 to 25-year periods after forest removal were significantly positively related to the age of the forest at the time it was cut. Eastern deciduous forests had been disturbed by logging or hurricane 12 to 56 years prior to forest removal, while Pacific Northwest conifer forests had been not experienced logging or wildfire for 90 to 450 years. Paired basin experiments provide a continuous, and continuously changing, record of vegetation structure, composition, and climate, and their effects on streamflow.

  5. NoWMex: Continuous GNSS Sites in Northwest Mexico

    NASA Astrophysics Data System (ADS)

    Gonzalez-Garcia, J. J.; Gonzalez-Ortega, J. A.

    2008-05-01

    Nowadays GPS has become part of daily life activities. In the near future, with the GPS modernization and the use of Glonass and Galileo as a Global Navigation Satellite System will give relative location precision from decimeters to millimeters in near real time applications. In order to realize this, we need a global array of continuously operating GNSS stations built to meet the standards of the geophysical communities and linked with gravimetric local measurements to discern the vertical component of our active Earth. Trying to follow this revolution, CICESE has been working with GPS since 1985. The GPS site CICE was built as an IGS reference station in 1995. Afterward we built 5 more continuous GPS sites in Northwest Mexico with the support of SCIGN. The CGPS NoWMex network is currently made up of six sites: CIC1, SPMX, CORX, GUAX, USMX and YESX (sopac.ucsd.edu). Recently, we implemented an experimental GPS processing lab as part of the Geodesy and Geodynamics Laboratory in the Seismology Department at CICESE. 30 stations are now currently processed from the network Red Geodesica Nacional Activa (RGNA-INEGI), NoWMex, and sites in neighbor countries. Fiducials solutions in ITRF2000 are obtained using GAMIT/GLOBK 10.31 with final igs orbits, every month since 2006. In order to make a contribution to densification of ITRF and support NAREF, SIRGAS and SNARF issues related to scientific and geomatics results; we are looking for internal (Mexican) and external colleagues as well as funding for maintenance and increase the number of CGNSS in NoWMeX including southern Basin and Ranger (Sonora, Chihuahua, Sinaloa and Durango), Gulf of California islands, Peninsular Californias, Nayarit, Jalisco, Colima and the Mexican Pacific islands: Guadalupe (2 more sites), Cedros, Socorro (DORIS site), Clarion and Tres Marias. We must to build more and free available CGNSS sites in and around Mexico to contribute to sea level rise and global change studies.

  6. Northwest outlet channels of Lake Agassiz, isostatic tilting and a migrating continental drainage divide, Saskatchewan, Canada

    NASA Astrophysics Data System (ADS)

    Fisher, Timothy G.; Souch, Catherine

    1998-10-01

    Lake cores obtained from the northwest outlet of glacial Lake Agassiz in northwest Saskatchewan, Canada, provide a minimum date for the cessation of the flood from the northwest outlet, and a chronology for abandonment of mid-Holocene channels that presently straddle the Mackenzie and Churchill drainage divide. The stratigraphy of a vibracore taken from Long Lake consists of a lower pebble gravel fining to massive sand, silty-clay and then fibrous peat. Wood fragments from the base of the clay yielded an accelerator mass spectrometry (AMS) date of 9120 BP. Because the lake is scour in origin and is in the head of the spillway, the date is considered to be a minimum estimate for cessation of the flood from the northwest outlet at the beginning of the Emerson Phase. A vibracore taken at Haas Lake in an abandoned channel surrounded by muskeg with no influent streams, consists of 0.8 m of stratified, pebble gravel containing abundant shell and wood fragments, overlain by 1.62 m of gyttja with a sharp, conformable lower contact. AMS dates range from 5590 BP from the topmost gravel to 3080 BP within the gyttja. The gravel is interpreted as fluvial, recording a river draining Wasekamio Lake north into the Clearwater River across the present-day drainage divide. Today, a drop of 2 m occurs from Wasekamio Lake southeast to Lac Ile-a-la-Crosse, along 150 km of lake basins parallel to the Cree Lake Moraine. The dates from Haas Lake suggest that before 5200 BP, the drainage divide was about 100 km further southeast, implying that during the Emerson Phase, lake level was controlled by a sill near Flatstone Lake at about 430 m instead of between Wasekamio Lake and the Clearwater River, as was previously proposed. Holocene differential isostatic uplift caused the flow reversal in the upper Churchill basin. Anastomosed channels at the mouth of rivers flowing north into lakes indicate that uplift is still active in the area today.

  7. 2. DETAIL VIEW OF MIDDLE ARCH SPAN, LOOKING NORTHWEST. ...

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

    2. DETAIL VIEW OF MIDDLE ARCH SPAN, LOOKING NORTHWEST. - Cumberland & Pennsylvania Railroad, Wills Creek Bridge, Spanning Wills Creek 587 feet West of Eckhart Junction, Cumberland, Allegany County, MD

  8. Oblique view of southeast corner; camera facing northwest. Mare ...

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

    Oblique view of southeast corner; camera facing northwest. - Mare Island Naval Shipyard, Defense Electronics Equipment Operating Center, I Street, terminus west of Cedar Avenue, Vallejo, Solano County, CA

  9. 9. FIRST FLOOR CAR BARN SPACE. VIEW TO NORTHWEST. ...

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

    9. FIRST FLOOR CAR BARN SPACE. VIEW TO NORTHWEST. - Commercial & Industrial Buildings, Key City Electric Street Railroad, Powerhouse & Storage Barn, Eighth & Washington Streets, Dubuque, Dubuque County, IA

  10. 8. STATIC TEST TOWER NORTHWEST ELEVATION FROM THE POWER ...

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

    8. STATIC TEST TOWER - NORTHWEST ELEVATION FROM THE POWER PLANT TEST STAND. - Marshall Space Flight Center, Saturn Propulsion & Structural Test Facility, East Test Area, Huntsville, Madison County, AL

  11. SOUTHEAST FRONT ELEVATION, LOOKING NORTHWEST, SHOWING PHILADELPHIA THANKSGIVING PARADE ...

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

    SOUTHEAST FRONT ELEVATION, LOOKING NORTHWEST, SHOWING PHILADELPHIA THANKSGIVING PARADE - Free Library of Philadelphia, Thomas Holme Branch, 7810 Frankford Avenue, Philadelphia, Philadelphia County, PA

  12. GRANT AVE., FROM SOUTHEAST OF BUILDING #191 (NORTHWEST CORNER OF ...

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

    GRANT AVE., FROM SOUTHEAST OF BUILDING #191 (NORTHWEST CORNER OF POPE & GRANT AVENUES), LOOKING NORTH-NORTHEAST - Fort Leavenworth, Metropolitan Avenue & Seventh Street, Leavenworth, Leavenworth County, KS

  13. GARAGE, SOUTH (REAR) AND EAST SIDE, LOOKING NORTHWEST Irvine ...

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

    GARAGE, SOUTH (REAR) AND EAST SIDE, LOOKING NORTHWEST - Irvine Ranch Agricultural Headquarters, Carillo Tenant House, Southwest of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  14. GARDEN (FOREGROUND), GARAGE (CENTER), AND PUMPHOUSE, LOOKING NORTHWEST Irvine ...

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

    GARDEN (FOREGROUND), GARAGE (CENTER), AND PUMPHOUSE, LOOKING NORTHWEST - Irvine Ranch Agricultural Headquarters, Carillo Tenant House, Southwest of Intersection of San Diego & Santa Ana Freeways, Irvine, Orange County, CA

  15. Northeast and northwest elevations. View to south Flint Creek ...

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

    Northeast and northwest elevations. View to south - Flint Creek Hydroelectric Project, Powerhouse, Approximately 3 miles southeast of Porters Corner on Powerhouse Road, Philipsburg, Granite County, MT

  16. Detail of door on southeast elevation. View to northwest ...

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

    Detail of door on southeast elevation. View to northwest - Flint Creek Hydroelectric Project, Powerhouse, Approximately 3 miles southeast of Porters Corner on Powerhouse Road, Philipsburg, Granite County, MT

  17. HUNT STABLE COMPLEX LOOKING NORTHWEST TOWARD DOG KENNEL RUINS ACROSS ...

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

    HUNT STABLE COMPLEX LOOKING NORTHWEST TOWARD DOG KENNEL RUINS ACROSS THE GREAT CIRCUS - Overhills, Fort Bragg Military Reservation, Approximately 15 miles NW of Fayetteville, Overhills, Harnett County, NC

  18. 7. VIEW NORTHWEST, DETAIL VERTICAL SUPPORT SYSTEM, STRINGER, CONNECTIONS AND ...

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

    7. VIEW NORTHWEST, DETAIL VERTICAL SUPPORT SYSTEM, STRINGER, CONNECTIONS AND TRAFFIC DECK - Hagerstown Road Bridge, Spanning Little Cotoctin Creek at Old Hagerstown Road, Middletown, Frederick County, MD

  19. 8. STATION 'L' FROM SOUTHEAST DIVISION STREET LOOKING NORTHWEST, LINCOLN ...

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

    8. STATION 'L' FROM SOUTHEAST DIVISION STREET LOOKING NORTHWEST, LINCOLN SUBSTATION IN FOREGROUND - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  20. 9. STATION 'L', LOOKING NORTHWEST FROM SOUTHEAST DIVISION, LINCOLN SUBSTATION ...

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

    9. STATION 'L', LOOKING NORTHWEST FROM SOUTHEAST DIVISION, LINCOLN SUBSTATION IN FOREGROUND - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

  1. VIEW OF SOUTHEASTERN INTERIOR SPACE, FACING NORTHWEST. Douglas Aircraft ...

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

    VIEW OF SOUTHEASTERN INTERIOR SPACE, FACING NORTHWEST. - Douglas Aircraft Company Long Beach Plant, Aircraft Parts Shipping & Receiving Building, 3855 Lakewood Boulevard, Long Beach, Los Angeles County, CA

  2. 26. VIEW, LOOKING NORTHWEST INSIDE TRANSFORMER ROOM, SHOWING OIL FILLED ...

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

    26. VIEW, LOOKING NORTHWEST INSIDE TRANSFORMER ROOM, SHOWING OIL- FILLED TRANSFORMER POTS - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  3. Sr isotopic evidence for fluid mixing in ore-stage dolomites, Pine Point, Northwest Territories, Canada

    NASA Astrophysics Data System (ADS)

    Gleeson, S. A.; Gromek, P.; Simonetti, A.

    2009-05-01

    The carbonate hosted Pb-Zn deposits of the Pine Point district (Northwest Territories) are located close to the eastern edge of the present day Western Canadian Sedimentary Basin. The deposits have been classified as Mississippi Valley Type deposits and are thought to have formed as the result of basin-wide fluid flow in the Presqu'ile barrier, the host to the ore deposits. Laser multi-collector ICP-MS study of 87Sr/86Sr ratios of ore- related dolomites from Pine Point indicate two sources of Sr were present in the mineralizing system. Fluid "A" has a range in Sr isotopic values from 0.07070 to 0.7120 and is a brine derived from Middle Devonian seawater which has undergone some interaction with clastic units in the basin. Fluid "B" has is more enriched in 87Sr and has 87Sr/86Sr ratios up to up to 0.7152, values similar to those found in Canadian Shield Brines, and represents a fluid which has interacted with crystalline basement rocks. The presence of this second Sr source in the ore forming system suggests that sulfide deposition at Pine Point occurred as a result of fluid mixing.

  4. [Land use pattern change in Ejin Delta of Northwest China during 1930-2010].

    PubMed

    Nian, Yan-yun; Wang, Xiao-li; Chen, Lu

    2015-03-01

    The land use and landscape pattern in the lower reaches of the arid inland river basin is meaningful to water resource allocation. Based on the land use data in 1930, 1961, 1990, 2000, 2010, the purpose of this study was to quantitatively analyze the change of landscape pattern in the Ejin Delta in the lower reaches of the Heihe River Basin, a typical inland river basin in Northwest China. The results showed that the desert area accounted for 73.4% of the total research area in 2010, and the grassland 20.8%. During the past 80 years, the grassland, farmland and construction land increased. The transformation of land use types were characterized by switching to farmland and construction land. The fragmentation and. diversity of the landscape increased, while the dominance of the landscape decreased. The landscape pattern obviously lied on the water resource and had regional diversity. Land use changes tended to make the landscape well-distributed, diverse and fragmentized. At last, the driving factors and ecological environment effects of land use change were discussed. In a word, to ensure harmonious development between human and eco-hydrology, suggestions such as planning ecological resettlement, limiting farmland area, developing precision agriculture and increasing the proportion of ecological water use should be put forward.

  5. Age constraints from northwest Russia on the global accumulation of carbon during the Palaeoproterozoic Shunga event

    NASA Astrophysics Data System (ADS)

    Martin, A. P.; Condon, D. J.; Prave, A. R.; Lepland, A.; Melezhik, V. A.

    2012-04-01

    The Palaeoproterozoic Shunga event records significant organic-carbon accumulation in sediments correlated between the type-locality in northwest Russia's Onega Basin, the Francevillian series of Gabon, and Indian Palaeoproterozoic sections. The estimated burial of >25 x 10E +10 tonnes of C in the Shunga event is significant and hypotheses have suggested this accumulation as one causal mechanism to the large positive Lomagundi-Jatuli positive carbon isotope excursion (CIE) of marine carbonates. Conversely, is has been suggested that the Shunga event post-dates the termination (at c. 2060 Ma) of the Lomagundi-Jatuli CIE and the two are not overlapping in time. Discrimination between these competing theories requires precise and accurate chronologies for the stratigraphic successions hosting the proxy records. We present new age constraints from a combination of primary volcanic rocks and sedimentary units recording the Shunga event, from the well preserved Palaeoproterozoic sections in the Pechenga Greenstone Belt (Kola craton) and Onega Paleo Basin (Karelia craton) northwest Russia, to further elucidate the unresolved question of timing between the Shunga event and the Lomagundi-Jatuli CIE. Carbon accumulations of the Shunga event are recorded in the Pilgujärvi Sedimentary Formation of the Pechenga Greenstone Belt. Felsic lava flows and pyroclastic rocks, and mafic pyroclastic rocks, in the Pilgujärvi Volcanic Formation overlying the Pilgujärvi sediments yield zircons with concordant U-Pb ages between c. 1970 and 1903 Ma. In the Pilgujärvi Sedimentary Formation detrital zircons yield a minimum age of c. 1922 Ma, equivalent to a minimum c. 1915 Ma age of detrital zircons in the underlying Kolosjoki Sedimentary Formation. Thrust over the main units of the Pechenga Greenstone Belt is a tectonic melange known as the South Pechenga Zone where zircons from an intermediate volcanic rock yield the first age from this zone at c. 1930 Ma. Samples from the Onega Basin are

  6. Pacific Northwest Storms Situation Report # 2

    SciTech Connect

    2006-12-16

    Severe wind and snow storms hit the Pacific Northwest region on December 14 – 15, 2006 resulting in major power outagesin the region. The storm is now moving off into southern Canada. A new weather disturbance nearing the Northwest coast may generate a few rain and snow showers across the Seattle and Portland areas today, but widespread active weather is not expected. There are roughly 950,000 customers in the region (including Canada) without power as a result of the Pacific Northweststorms, down from a peak of 1.8 million customers. This represents about 26 percent of customers in affected utility service areas in Oregon and Washington. See table below. As of 12:30 PM EST, the Renton Control Center for the Olympic Pipeline (petroleum products) had power restored. The pipeline, serviced by Puget Sound Energy, was shut down after it lost power during the storm. According to a pipeline official, the pipeline is expected to restart in approximately 2-3 hours with some reduced throughput later today. SeaTac International Airport receives jet fuel from the pipeline; however, it’s been reported that the airport has approximately eight days of jet fuel inventories on hand. There are no reports of problems regarding fuel production. There are some temporary and minor distribution at retail gas stations due to lack of power. Fuel delivery is also slowed in some areas due to delays on some roads. ESF #12 has not been deployed

  7. Northwest Region Clean Energy Application Center

    SciTech Connect

    Sjoding, David

    2013-09-30

    The main objective of the Northwest Clean Energy Application Center (NW CEAC) is to promote and support implementation of clean energy technologies. These technologies include combined heat and power (CHP), district energy, waste heat recovery with a primary focus on waste heat to power, and other related clean energy systems such as stationary fuel cell CHP systems. The northwest states include AK, ID, MT, OR, and WA. The key aim/outcome of the Center is to promote and support implementation of clean energy projects. Implemented projects result in a number of benefits including increased energy efficiency, renewable energy development (when using opportunity fuels), reduced carbon emissions, improved facility economics helping to preserve jobs, and reduced criteria pollutants calculated on an output-based emissions basis. Specific objectives performed by the NW CEAC fall within the following five broad promotion and support categories: 1) Center management and planning including database support; 2) Education and Outreach including plan development, website, target market workshops, and education/outreach materials development 3) Identification and provision of screening assessments & feasibility studies as funded by the facility or occasionally further support of Potential High Impact Projects; 4) Project implementation assistance/trouble shooting; and 5) Development of a supportive clean energy policy and initiative/financing framework.

  8. Characteristics of aeolian dust across northwest Australia

    NASA Astrophysics Data System (ADS)

    Karlson, L. R.; Greene, R. S. B.; Scott, K. M.; Stelcer, E.; O'Loingsigh, T.

    2014-03-01

    South easterly trade winds have long been thought to transport aeolian dust across northwest Australia, but very little is known about the chemical and particle size characteristics of this material. From July 2008 to May 2009, 36 aeolian dust samples were collected monthly at four sites across Australia's northwest. The results of ion beam analysis indicate that the samples consisted of four major elemental groups, one of which appeared to be transported across the sites during months in winter and summer. This group (characterised by higher ratios of Fe, Ti and Mn/Si than the Earth's Crustal Average) also showed a decrease in particle sizes towards the west. This suggests that the dust may have had a central Australian source, while other groups richer in Si appear to have been locally derived. These results support previous models of seasonal dust transport, and may have relevance in regional climate modelling, the transport of nutrients into the Indian Ocean, mineral exploration and studies of respiratory health.

  9. Ice Thickness in the Northwest Passage

    NASA Astrophysics Data System (ADS)

    Haas, C.; Howell, S.

    2015-12-01

    Recently the feasibility of commercial shipping in the ice-prone Northwest Passage has attracted a lot of attention. However, very little ice thickness information actually exists. We present results of the first-ever airborne electromagnetic ice thickness surveys over the NWP carried out in April and May 2011 and 2015 over first-year and multiyear ice. Results show modal thicknesses between 1.8 and 2.0 m in all regions. Mean thicknesses over 3 m and thick, deformed ice were observed over some multiyear ice regimes shown to originate from the Arctic Ocean. Thick ice features more than 100 m wide and thicker than 4 m occurred frequently. There are few other data to compare with to evaluate if the ice of the Northwest Passage has transitioned as other parts of the Arctic have. Although likely thinner than some 20 or more years ago, ice conditions must still be considered severe, and the Canadian Arctic Archipelao may well be considered the last ice refuge of the Arctic. These results have important implications for the prediction of ice break-up and summer ice conditions, and the assessment of sea ice hazards during the summer shipping season.

  10. Play concepts-northwest Palawan, Philippines

    NASA Astrophysics Data System (ADS)

    Williams, Harold H.

    The offshore area of northwest Palawan, Philippines, contains a number of provenexploration plays. These include • pinnacle reefs developed on Nido carbonate platforms (e.g. Nido, Matinloc, Cadlao);• a seaward horst block reef fairway with large pinnacle reefs (e.g. Malampaya—Camago trend);• early Miocene Galoc Clastic Unit turbidites (e.g. Octon, Galoc); and• four-way dip closures (e.g. West Linapacan, Octon). The recent discovery by Fletcher Challenge Petroleum at Calauit Field has shown a potentialexploration play in deep-water Nido Limestone turbidites. The traditional and, to date, only economically productive play in northwest Palawan has been the Nido Limestone reefs. This paper presents a review of the old play types and presents new untested play types. These new play types include • pre-Nido syn-rift plays;• pre-Nido marine turbidite play: and• mid-Miocene reefs. It also presents new insights into factors controlling reef development on the carbonate platforms where four reef types are now recognized. The Galoc Clastic Unit turbidite play is discussed and new play fairways presented.

  11. 2006 Pacific Northwest Loads and Resources Study.

    SciTech Connect

    United States. Bonneville Power Administration.

    2006-03-01

    The Pacific Northwest Loads and Resources Study (White Book), which is published annually by the Bonneville Power Administration (BPA), establishes one of the planning bases for supplying electricity to customers. The White Book contains projections of regional and Federal system load and resource capabilities, along with relevant definitions and explanations. The White Book also contains information obtained from formalized resource planning reports and data submittals including those from individual utilities, the Northwest Power and Conservation Council (Council), and the Pacific Northwest Utilities Conference Committee (PNUCC). The White Book is not an operational planning guide, nor is it used for determining BPA revenues, although the database that generates the data for the White Book analysis contributes to the development of BPA's inventory and ratemaking processes. Operation of the Federal Columbia River Power System (FCRPS) is based on a set of criteria different from that used for resource planning decisions. Operational planning is dependent upon real-time or near-term knowledge of system conditions that include expectations of river flows and runoff, market opportunities, availability of reservoir storage, energy exchanges, and other factors affecting the dynamics of operating a power system. The load resource balance of both the Federal system and the region is determined by comparing resource availability to an expected level of total retail electricity consumption. Resources include projected energy capability plus contract purchases. Loads include a forecast of retail obligations plus contract obligations. Surplus energy is available when resources are greater than loads. This surplus energy could be marketed to increase revenues. Energy deficits occur when resources are less than loads. These energy deficits will be met by any combination of the following: better-than-critical water conditions, demand-side management and conservation programs

  12. Integrated remote sensing data utilization for investigating structural and tectonic history of the Ghadames Basin, Libya

    NASA Astrophysics Data System (ADS)

    Saadi, N. M.; Zaher, M. Abdel; El-Baz, F.; Watanabe, K.

    2011-10-01

    This study was initiated to constrain the geological structure of the Ghadames Basin in northwest Libya. Detailed analysis was based on digital integration of surface data, including SRTM DEM, ETM+ and geologic maps with subsurface data, including well logs and potential field data. Integrated analysis of remotely sensed data of the SRTM and ETM+ were utilized to identify geologic lineaments in the area. Ground-based verification of the remote sensing data was achieved with field work. Interpretation and analysis of the lineaments indicate that the Ghadames Basin is controlled by four main fault systems that trend WNW, NNW, NW and ENE. Well logs and potential field data were used to delineate a detailed picture of the subsurface structure. The potential field data reveal two NE and NNE trending sedimentary basins. The depth of the basement inside the main basin ranges from 2 to 6 km. A two-dimensional (2-D) schematic model shows that the basin gradually deepens towards the southwest. The applied data integration gave new insight into the tectonic and structure patterns of the Ghadames Basin and the adjacent areas of northwest Libya.

  13. Genetic structure of lake whitefish, Coregonus clupeaformis, populations in the northern main basin of Lake Huron

    USGS Publications Warehouse

    Stott, Wendylee; Ebener, Mark P.; Mohr, Lloyd; Schaeffer, Jeff; Roseman, Edward F.; Harford, William J.; Johnson, James E.; Fietsch, Cherie-Lee

    2012-01-01

    Genetic analysis of spawning lake whitefish (Coregonus clupeaformis) from six sites in the main basin of Lake Huron was conducted to determine population structure. Samples from fisheryindependent assessment surveys in the northwest main basin were analyzed to determine the relative contributions of lake whitefish genetic populations. Genetic population structure was identified using data from seven microsatellite DNA loci. One population was identified at Manitoulin Island, one to two were observed in the east-central main basin (Fishing Island and Douglas Point), and one to two populations were found in the northwest (Thunder Bay and Duncan Bay). The genetic identity of collections from Duncan Bay and Thunder Bay was not consistent among methods used to analyze population structure. Low genetic distances suggested that they comprised one population, but genic differences indicated that they may constitute separate populations. Simulated data indicated that the genetic origins of samples from a mixed-fishery could be accurately identified, but accuracy could be improved by incorporating additional microsatellite loci. Mixture analysis and individual assignment tests performed on mixed-stock samples collected from the western main basin suggested that genetic populations from the east-central main basin contributed less than those from the western main basin and that the proportional contribution of each baseline population was similar in each assessment sample. Analysis of additional microsatellite DNA loci may be useful to help improve the precision of the estimates, thus increasing our ability to manage and protect this valuable resource.

  14. Simulation of Populus euphratica root uptake of groundwater in an arid woodland of the Ejina basin, China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Ejina Basin is an extremely arid subwatershed in Northwest China. The predominant natural tree species in the area, Populus euphratica (P. euphratica), depends on groundwater for sustenance. In recent decades, groundwater overdraft and increased water diversions from the Heihe River caused wat...

  15. Cryopreservation of Adult Male Spring and Summer Chinook Salmon Gametes in the Snake River Basin, 1997 Annual Report.

    SciTech Connect

    Faurot, Dave; Kucera, Paul A.; Armstrong, Robyn D.

    1998-06-01

    Chinook salmon populations in the Northwest are decreasing in number. The Nez Perce Tribe was funded in 1997 by the Bonneville Power Administration to coordinate and initiate gene banking of adult male gametes from Endangered Species Act (ESA) listed spring and summer chinook salmon in the Snake River basin.

  16. Eastern Venezuela Basin's Post-Jurassic evolution as a passive transform margin basin

    SciTech Connect

    George, R.P. Jr. ); Sams, R.H. )

    1993-02-01

    Passive transform margins are segments of rifted continental margins bounded by transform faults that are active during rifting and that become inactive during drifting. Examples include the northern coast of Brazil and its matching margin along the Liberia-Nigeria coast. We propose that the northern margin of the Eastern Venezuela Basin was dominantly a passive transform margin during the Cretaceous and early Paleogene, rather than a purely passive margin. Published microplate reconstructions of the southern Caribbean show Jurassic separation of the Bahamas platform from northern South America along a northwest-trending transform fault postulated to lie just northeast of Trinidad and the Guianas. We conjecture that the [open quotes]Deflexion de Barcelona[close quotes] (a northwest-trending zone of strike slip faults along the southwestern edge of the Serrania del Interior) is controlled by a basement geofracture that is the onshore expression of Jurassic transform fault southwest of and subparallel to the southwestern Bahamas transform. Implications of this conjecture for the Eastern Venezuela Basin include: (1) absence of McKenzie-type regional crustal stretching, Mesozoic thermal anomaly, and Mesozoic thermal-tectonic subsidence; (2) abrupt rather than gradual seaward changes in crustal thickness; (3)abrupt lateral changes in thickness and facies of Mesozoic sediments, as in the Piaui-Ceara basins of northern Brazil; (4) tendency for structural styles developed during Neogene compression to include more strike-slip faults and en enchelon fold sets (because of reactivation of Mesozoic transforms) than would be expected by structural inversion of a purely passive margin.

  17. Geology and hydrocarbon potential of the Oued Mya basin, Algeria

    SciTech Connect

    Benamrane, O.; Messaoudi, M.; Messelles, H. )

    1993-09-01

    The Oued Mya hydrocarbon system is located in the Sahara basin. It is one of the best producing basins in Algeria, along with the Ghadames and Illizi basins. The stratigraphic section consists of Paleozoic and Mesozoic, and is about 5000 m thick. This intracratonic basin is limited to the north by the Toughourt saddle, and to the west and east it is flanked by regional arches, Allal-Tilghemt and Amguid-Hassi Messaoud, which culminate in the super giant Hassi Messaoud and Hassi R'mel hydrocarbon accumulations, respectively, producing oil from the Cambrian sands and gas from the Trissic sands. The primary source rock in this basin is lower Silurian shale, with an average thickness of 50 m and a total organic carbon of 6% (14% in some cases). Results of maturation modeling indicate that the lower Silurian source is in the oil window. The Ordovician shales are also source rocks, but in a second order. Clastic reservoirs are in the Trissic sequence, which is mainly fluvial deposits with complex alluvial channels, and the main target in the basin. Clastic reservoirs in the lower Devonian section have a good hydrocarbon potential east of the basin through a southwest-northwest orientation. The Late Trissic-Early Jurassic evaporites that overlie the Triassic clastic interval and extend over the entire Oued Mya basin, are considered to be a super-seal evaporite package, which consists predominantly of anhydrite and halite. For paleozoic targets, a large number of potential seals exist within the stratigraphic column. This super seal does not present oil dismigration possibilities. We can infer that a large amount of the oil generated by the Silurian source rock from the beginning of Cretaceous until now still is not discovered and significantly greater volumes could be trapped within structure closures and mixed or stratigraphic traps related to the fluvial Triassic sandstones, marine Devonian sands, and Cambrian-Ordovician reservoirs.

  18. Origin of arches in the northwestern Gulf of Mexico basin

    SciTech Connect

    Laubach, S.E.; Jackson, M.L.W. )

    1990-07-01

    The San Marcos and Sabine arches are prominent north- to northwest-trending basement uplifts in the northwestern Gulf of Mexico basin that may be late Mesozoic to Cenozoic foreland or intraplate folds rather than domes over plutons or buoyant basement blocks. These arches are subparallel to and contemporaneous with orogenic episodes in the northwest-trending fold-thrust belt of Mexico. Arch movement was also contemporaneous with rapid convergence between the North American and Pacific plates. Arch development in the gulf as a result of tectonic compression is plausible in view of increasing recognition of wide zones of foreland and intraplate deformation in continents. Current tectonic models of the development of the gulf inaccurately predict gradual, decelerating subsidence when these arches were most active.

  19. Middle Proterozoic belt basin syndepositional faults and their influence on Phanerozoic thrusting and extension

    SciTech Connect

    Winston, D.

    1983-08-01

    During the middle Proterozoic, continental crust of the Belt region was cut by nearly east-west and northwest-striking faults that produced a mosaic of large basement blocks. Blocks that subsided formed the Belt basin and were surrounded mostly by uplifted blocks. The Dillon block bounded the basin on the south along the Perry line, and, together with blocks to the south and west, furnished most of the sediment that filled the basin. Great alluvial aprons sloped basinward from the uplifted blocks down to extensive flats that bordered the Belt intracratonic sea. Sediments were deposited in the deeper parts of the sea by underflows and interflows. The graben blocks, including the Helena embayment and the diagonal block to the northwest, received the thickest sediments. Cretaceous to Paleocene compression thrust the Belt rocks and Phanerozoic cover rocks eastward and northeastward, forming first a western, and then an eastern thrust belt. Thrusts on the blocks formed long sheets that deflected and tore along the block boundaries, where depth to basement and tectonic transport distances changed. Where thrust crossed northwest-trending basement faults, they ramped locally. Eocene extension produced fault patterns that change from block to block. Differential extension formed right-lateral strike-slip faults across block boundaries. Proterozoic faults that cut the continental crust, not only formed the framework of the Belt basin, but affected patterns of later compression and extension.

  20. Structural control on paleovalley development, muddy sandstone, Powder River basin, Wyoming

    SciTech Connect

    Gustason, E.R.; Wheeler, D.A.; Ryer, T.A.

    1988-07-01

    A subaerial unconformity within the Lower Cretaceous Muddy Sandstone in the Powder River basin developed during a late Albian sea level lowstand and resulted in a markedly rectangular drainage pattern. Numerous right-angle bends and perpendicular confluences of Muddy paleovalleys are believed to reflect syndepositional movement on basement faults and dissolution of salts in the Goose Egg Formation. A detailed subsurface analysis of geophysical logs from closely spaced wells reveals that up to 30 ft of vertical displacement occurred along northwest- and northeast-trending faults prior to and during the development of the subaerial unconformity. An analysis of a high-resolution magnetic survey (NewMag) of the Powder River basin reveals that numerous paleovalleys parallel the boundaries, or basement shear zones, between basement blocks. Small, irregularly shaped, thin intervals of the Permian Goose Egg Formation, which resemble karst topography, also occur along these northwest- and northeast-trending basement faults beneath Muddy paleovalleys. An arcuate Muddy paleovalley located in the northern Powder River basin parallels contours of isopach and trend surface maps of the Goose Egg Formation. These relationships suggest that the location and orientation of Muddy paleovalleys were controlled by a combination of movement along northwest- and northeast-trending faults and syntectonic dissolution of salt within the Goose Egg Formation. Simultaneous dissolution of Goose Egg salts and headward erosion of Muddy paleovalleys along this conjugate fault pattern also indicate that the Powder River basin was influenced by wrench fault tectonics during the late Albian.

  1. Origin of the Permian-Triassic Iberian Basin, central-eastern Spain

    NASA Astrophysics Data System (ADS)

    Arche, Alfredo; López-Gómez, José

    1996-12-01

    The Iberian Basin was an intracratonic rift basin in central-eastern Spain developed since Early Permian times. The basin boundary faults were normal, listric faults controlling an asymmetric extension propagating northeast with time. Hercynian or older lineaments controlled the orientation of the Iberian Basin and extension was accommodated basically in the hanging wall block by the formation of secondary grabens and a central high. The basin was related with the coeval Ebro, Catalan and Cuenca-Mancha Basins and their connections are discussed. Subsidence curves show that the Early Permian-Early Jurassic period of extension can be subdivided into three rifting episodes and a flexural one. Extension factor increases from 1.17 in the northwest to 1.29 near the Mediterranean coast. The increasing extension rate was accommodated by transfer faults trending NNE-SSW, more important in the Levante area. The rift evolution is intermittent and seems to reflect distinct stress fields. The collapse of the late Hercynian orogen and related increased heat flux, extension and rifting is the most probable origin of the Iberian Basin and related basins. The origin of the Catalan and the Valencia-Prebetic Basins is related to the southwards migration of the Hesse-Burgundy Rift along the eastern margin of the Iberian Microplate.

  2. 21. General interior overview, dock no. 492. View to northwest. ...

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

    21. General interior overview, dock no. 492. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  3. 18. General interior overview, dock no. 491. View to northwest. ...

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

    18. General interior overview, dock no. 491. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  4. 12. Northwest end and southwest rear, dock no. 493. Access ...

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

    12. Northwest end and southwest rear, dock no. 493. Access road in foreground. View to east. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  5. 4. Northeast front and northwest side of original section and ...

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

    4. Northeast front and northwest side of original section and addition. View to south. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  6. 6. Northeast rear and northwest end, dock no. 492. View ...

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

    6. Northeast rear and northwest end, dock no. 492. View to south. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  7. 2. Northwest end and northeast rear, dock no. 491. View ...

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

    2. Northwest end and northeast rear, dock no. 491. View to south. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  8. 20. General interior overview, dock no. 493. View to northwest. ...

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

    20. General interior overview, dock no. 493. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Nose Docks, On either side of Hangar Access Apron at Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  9. 7 CFR 1124.2 - Pacific Northwest marketing area.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pacific Northwest marketing area. 1124.2 Section 1124.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA...

  10. 1. VIEW LOOKING NORTHWEST AT BUILDING 701. BUILDING 701 WAS ...

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

    1. VIEW LOOKING NORTHWEST AT BUILDING 701. BUILDING 701 WAS USED TO DESIGN, BUILD, AND EVALUATE BENCH-SCALE TECHNOLOGIES USED IN ROCKY FLATS WASTE TREATMENT PROCESSES. (1/98) - Rocky Flats Plant, Design Laboratory, Northwest quadrant of Plant, between buildings 776-777 & 771, Golden, Jefferson County, CO

  11. 42. INTERIOR, FIRST FLOOR, NORTHWEST CORNER OF GRAND STAIRCASE (STAIRS ...

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

    42. INTERIOR, FIRST FLOOR, NORTHWEST CORNER OF GRAND STAIRCASE (STAIRS G), SIDE AISLE, WEST WALL, THE NEGRO'S CONTRIBUTION IN THE SOCIAL AND CULTURAL DEVELOPMENT OF AMERICA: SCIENCE MURAL - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

  12. 23. General view of the top gundeck looking northwest from ...

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

    23. General view of the top gundeck looking northwest from Austria Bastion showing ramp down and parapet wall of the Plaza de Armas on lower level - Castillo de San Felipe del Morro, Northwest end of San Juan, San Juan, San Juan Municipio, PR

  13. Aerial view northwest from center of square showing upper portion ...

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

    Aerial view northwest from center of square showing upper portion of rear walls of 519 Eleventh Street, 521 Eleventh Street, 523 Eleventh Street, 525 Eleventh Street, 1008-1010 F Street, and 1012 F Street - Square 347 (Commercial Buildings), Tenth, Eleventh, E, & F Streets, Northwest, Washington, District of Columbia, DC

  14. 77 FR 48132 - Gas Transmission Northwest, LLC; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-13

    ... Energy Regulatory Commission Gas Transmission Northwest, LLC; Notice of Application Take notice that on July 31, 2012, Gas Transmission Northwest, LLC (GTN), filed in Docket No. CP12-494-000, an application pursuant to section 7(c) of the Natural Gas Act (NGA) and Part 157 of the Commission's...

  15. 76 FR 5796 - Gas Transmission Northwest Corporation; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-02

    ... Energy Regulatory Commission Gas Transmission Northwest Corporation; Notice of Application January 26, 2011. Take notice that on January 14, 2011, Gas Transmission Northwest Corporation (GTN), 717 Texas... application under section 7(b) of the Natural Gas Act for permission and approval to abandon certain...

  16. POLICY CONUNDRUM: RESTORING WILD SALMON TO THE PACIFIC NORTHWEST

    EPA Science Inventory

    Across the Pacific Northwest region of North America, many runs of wild (in contrast to hatchery-bred) salmon have declined and some have been extirpated. Restoring wild salmon runs to the Pacific Northwest is technically challenging, politically nasty, socially divisive, and ...

  17. Interior view of the northwest end corridor, showing doors and ...

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

    Interior view of the northwest end corridor, showing doors and barred openings to former fan and engine rooms (now garage) and entry to northwest gun chamber (labeled "Gun Turret No. One") - U.S. Naval Base, Pearl Harbor, Battery Adair, Princeton Place, Pearl City, Honolulu County, HI

  18. 15. INTERIOR OF NORTHWEST BEDROOM SHOWING OPEN DOORS TO ATTIC ...

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

    15. INTERIOR OF NORTHWEST BEDROOM SHOWING OPEN DOORS TO ATTIC ACCESS AT PHOTO LEFT AND BATHROOM AT PHOTO CENTER. ORIGINAL 1-LIGHT OVER 1-LIGHT, DOUBLE HUNG WINDOW AT PHOTO RIGHT. VIEW TO NORTHWEST. - Bishop Creek Hydroelectric System, Plant 4, Worker Cottage, Bishop Creek, Bishop, Inyo County, CA

  19. 78 FR 782 - Energy Northwest; Columbia Generating Station; Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-04

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Energy Northwest; Columbia Generating Station; Exemption 1.0 Background Energy Northwest (the licensee) is the holder of Renewed Facility Operating License No. NPF-21, which authorizes operation of the Columbia Generating Station. The...

  20. Urbanization in the Northwest. Issues and Implications for Policy.

    ERIC Educational Resources Information Center

    Martinez, Michele

    In the Northwest, as across the rest of the United States, the basic characteristics of the U.S. household are changing. In demographic and economic terms, the Northwest is at the forefront of changes predicted for the entire country in the coming century. Urbanization is occurring in a region that was once defined by the relationship of human…

  1. 14. INTERIOR OF ROOM 101 LOOKING NORTHWEST. SIX OVER SIX ...

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

    14. INTERIOR OF ROOM 101 LOOKING NORTHWEST. SIX OVER SIX LITE WOOD FRAME WINDOWS ARE CENTERED ON NORTHEAST AND NORTHWEST WALLS. ADDED TREATMENT TO WALLS IS A GYPSUM BOARD FINISH WITH WOOD TRIM, BOTH PAINTED. ADDED FLOOR TREATMENT IS VINYL COMPOSITION TILE. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA

  2. The Northwest Ordinance and Constitutional Development in Indiana.

    ERIC Educational Resources Information Center

    Madison, James H.

    The Northwest Ordinance of 1787 is a fundamental document in the development of the United States. It is outranked in importance only by the Declaration of Independence and the Constitution. The immediate purpose of the Northwest Ordinance was to provide government for the largely unsettled lands north and west of the Ohio River. In promising…

  3. 5. View of northwest corner of East Ward Street and ...

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

    5. View of northwest corner of East Ward Street and Dewey Avenue, facing northwest. - Gaskin Avenue Neighborhood, Bounded by Dart Street to east, CSX Railroad to south, Pearl & Madison Avenues to west, & Wilson & Gordon Streets to north, Douglas, Coffee County, GA

  4. Route No. 1 in northwest portion of recorded segment, in ...

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

    Route No. 1 in northwest portion of recorded segment, in Sand Denes Topographical Area, view to north-northwest - Route No. 1-Overton-Lake Mead Road, Between Overton Beach & Park Boundary, 6 miles south of Overton, Overton, Clark County, NV

  5. 7 CFR 1124.2 - Pacific Northwest marketing area.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Pacific Northwest marketing area. 1124.2 Section 1124.2 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE PACIFIC NORTHWEST MARKETING AREA...

  6. Changing Sea Ice Conditions in the Northwest Passage

    NASA Astrophysics Data System (ADS)

    Tivy, A. C.; Howell, S.; Agnew, T.; Derksen, C.

    2010-12-01

    The Northwest Passage lies in the middle of Canadian Arctic Archipelago providing a potential deepwater route that links the Atlantic and Pacific Oceans. Discovered by Sir Robert M’Clure in the 1850s, ever-present multi-year ice (MYI) has always prevented its practical navigation. 2007 marked extreme low MYI conditions in the Arctic and temporarily cleared the Northwest Passage. However, is one single clearing event within the Northwest Passage over the past 40 years indicative of future clearings? This analysis addressed two inter-related questions: i) why has the Northwest Passage contained historically heavy amounts of MYI? and ii) will decreases in MYI within the Northwest Passage continue into the future? Results indicate that for nearly 4 decades, the southern regions of the Canadian Arctic Archipelago have continuously operated as a drain-trap for MYI and this mechanism is responsible for maintaining the heavy MYI conditions within the Northwest Passage. The oldest and thickest MYI in the world resides along the northern flank of the Canadian Arctic Archipelago therefore, as the transition to a sea ice-free Arctic continues, MYI from this region will continue to migrate southward to the channels of the Northwest Passage. Results also find that 2007 was indeed an anomalously light sea ice year in the Northwest Passage but record low ice conditions have since been observed as of mid-August 2010.

  7. Revisiting a classification scheme for U.S.-Mexico alluvial basin-fill aquifers.

    PubMed

    Hibbs, Barry J; Darling, Bruce K

    2005-01-01

    Intermontane basins in the Trans-Pecos region of westernmost Texas and northern Chihuahua, Mexico, are target areas for disposal of interstate municipal sludge and have been identified as possible disposal sites for low-level radioactive waste. Understanding ground water movement within and between these basins is needed to assess potential contaminant fate and movement. Four associated basin aquifers are evaluated and classified; the Red Light Draw Aquifer, the Northwest Eagle Flat Aquifer, the Southeast Eagle Flat Aquifer, and the El Cuervo Aquifer. Encompassed on all but one side by mountains and local divides, the Red Light Draw Aquifer has the Rio Grande as an outlet for both surface drainage and ground water discharge. The river juxtaposed against its southern edge, the basin is classified as a topographically open, through-flowing basin. The Northwest Eagle Flat Aquifer is classified as a topographically closed and drained basin because surface drainage is to the interior of the basin and ground water discharge occurs by interbasin ground water flow. Mountains and ground water divides encompass this basin aquifer on all sides; yet, depth to ground water in the interior of the basin is commonly >500 feet. Negligible ground water discharge within the basin indicates that ground water discharges from the basin by vertical flow and underflow to a surrounding basin or basins. The most likely mode of discharge is by vertical, cross-formational flow to underlying Permian rocks that are more porous and permeable and subsequent flow along regional flowpaths beneath local ground water divides. The Southeast Eagle Flat Aquifer is classified as a topographically open and drained basin because surface drainage and ground water discharge are to the adjacent Wildhorse Flat area. Opposite the Eagle Flat and Red Light Draw aquifers is the El Cuervo Aquifer of northern Chihuahua, Mexico. The El Cuervo Aquifer has interior drainage to Laguna El Cuervo, which is a phreatic

  8. Revisiting a classification scheme for U.S.-Mexico alluvial basin-fill aquifers.

    PubMed

    Hibbs, Barry J; Darling, Bruce K

    2005-01-01

    Intermontane basins in the Trans-Pecos region of westernmost Texas and northern Chihuahua, Mexico, are target areas for disposal of interstate municipal sludge and have been identified as possible disposal sites for low-level radioactive waste. Understanding ground water movement within and between these basins is needed to assess potential contaminant fate and movement. Four associated basin aquifers are evaluated and classified; the Red Light Draw Aquifer, the Northwest Eagle Flat Aquifer, the Southeast Eagle Flat Aquifer, and the El Cuervo Aquifer. Encompassed on all but one side by mountains and local divides, the Red Light Draw Aquifer has the Rio Grande as an outlet for both surface drainage and ground water discharge. The river juxtaposed against its southern edge, the basin is classified as a topographically open, through-flowing basin. The Northwest Eagle Flat Aquifer is classified as a topographically closed and drained basin because surface drainage is to the interior of the basin and ground water discharge occurs by interbasin ground water flow. Mountains and ground water divides encompass this basin aquifer on all sides; yet, depth to ground water in the interior of the basin is commonly >500 feet. Negligible ground water discharge within the basin indicates that ground water discharges from the basin by vertical flow and underflow to a surrounding basin or basins. The most likely mode of discharge is by vertical, cross-formational flow to underlying Permian rocks that are more porous and permeable and subsequent flow along regional flowpaths beneath local ground water divides. The Southeast Eagle Flat Aquifer is classified as a topographically open and drained basin because surface drainage and ground water discharge are to the adjacent Wildhorse Flat area. Opposite the Eagle Flat and Red Light Draw aquifers is the El Cuervo Aquifer of northern Chihuahua, Mexico. The El Cuervo Aquifer has interior drainage to Laguna El Cuervo, which is a phreatic

  9. BOLIVAR Project: A New Model for Grenada and Tobago Basin Evolution

    NASA Astrophysics Data System (ADS)

    Christeson, G. L.; Mann, P.; Escalona, A.

    2005-12-01

    The Grenada basin, located in the SE Caribbean, is bounded to the northwest by the Aves Ridge and to the southeast by the Lesser Antilles Arc and Tobago basin. Existing tectonic models for Grenada basin evolution are based on the assumption that the Grenada basin fits into the traditional backarc model, with the Grenada basin formed by rifting of the Lesser Antilles arc away from the Aves Ridge. However our analysis of new seismic reflection and refraction data, acquired during the 2004 BOLIVAR program, suggests that the Grenada and Tobago basins were connected as a single basin during the Paleogene. Uplift of the Lesser Antilles arc and associated platform initiated during early to middle Miocene; the arc formed a barrier to sedimentation between the two basins by the late Miocene. We suggest a new tectonic model for evolution of these basins: 1) Paleogene extension of at least 70 km of the preexisting forearc of the Great Arc of the Caribbean (Aves Ridge) by the mechanisms of slab rollback and flexural subsidence. 2) Flexural and thermal subsidence ceases in the middle Eocene, producing a wide, deep-marine forearc basin encompassing the present-day Grenada and Tobago basins. 3) Oblique plate convergence between the Caribbean and South American plates causes a backthrust response in the weakened and thinned crust of the Grenada/Tobago forearc basin during the late Oligocene to middle Miocene. 4) Magmatism in the Lesser Antilles arc builds a ridge on the inverted forearc that becomes a major sediment barrier between the Grenada and Tobago basins during post-middle Miocene.

  10. Fault-controlled sedimentation in a progressively opening extensional basin: the Palaeoproterozoic Vargfors basin, Skellefte mining district, Sweden

    NASA Astrophysics Data System (ADS)

    Bauer, Tobias E.; Skyttä, Pietari; Allen, Rodney L.; Weihed, Pär

    2013-03-01

    The Vargfors basin in the central part of the Skellefte mining district is an inverted sedimentary basin within a Palaeoproterozoic (1.89 Ga) marine volcanic arc. The fault-segmented basin formed from upper-crustal extension and subsequent compression, following a period of intense sub-marine volcanism and VMS ore formation. New detailed mapping reveals variations in stratigraphy attributed to syn-extensional sedimentation, as well as provenance of conglomerate clasts associated with tectonic activity at the transition from extension to compression. The onset of fan delta to alluvial fan sedimentation associated with basin subsidence indicates that significant dip-slip displacement accommodating rapid uplift of the intrusive complex and/or subsidence of the adjacent volcano-sedimentary domain took place along a major fault zone at the southern margin of the intrusive complex. Subsidence of the Jörn intrusive complex and/or its burial by sedimentary units caused a break in erosion of the intrusion and favoured the deposition of a tonalite clast-barren conglomerate. Clast compositions of conglomerates show that the syn-extensional deposits become younger in the south-eastern parts of the basin, indicating that opening of the basin progressed from north-west to south-east. Subsequent basin inversion, associated with the accretion to the Karelian margin, involved reverse activation of the normal faults and development of related upright synclines. Progressive crustal shortening caused the formation of break-back faults accompanied by mafic volcanic activity that particularly affected the southern contact of the Jörn intrusive complex and the northern contact of the Vargfors basin.

  11. 78 FR 46563 - Endangered and Threatened Species: Proposed Rule To Designate Critical Habitat for the Northwest...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-01

    ... Species: Proposed Rule To Designate Critical Habitat for the Northwest Atlantic Ocean Loggerhead Sea... Designate Critical Habitat for the Northwest Atlantic Ocean Loggerhead Sea Turtle Distinct Population... proposes designation of critical habitat for the threatened Northwest Atlantic Ocean Distinct...

  12. Stratigraphic correlation of the Late Cretaceous Simsima Formation United Arab Emirates and Akveren Formation, northwest Turkey

    NASA Astrophysics Data System (ADS)

    Abdelghany, O.; Abu Saima, M.; Ramazanoglu, S.; Arman, H.

    2015-11-01

    Latest Cretaceous (Campanian-Maastrichtian) microfossils are used to correlate the carbonate rocks of the Simsima Formation in the northeastern part of the Arabian Peninsula (Northern Oman Mountains, United Arab Emirates and Oman) with the Akveren Formation in Kandira (northwest Turkey, near Black Sea region). Both formations have characteristically rich planktonic foraminiferal and calcareous nannofossil faunal assemblages that permit the recognition of the Globotruncanella havanensis Zone and Quadrum sissinghii Zone CC22. The palaeontological data is used to build an appropriate palaeoenvironmental model for the latest Cretaceous Aruma Group in the Oman Mountains foreland basin. The study reveals that the Late Cretaceous formations of UAE and Turkey can be divided into an open marine carbonate shelf facies (planktonic foraminifera/calcareous nannofossil biomicrite) and a shallow-marine carbonate facies (rudistids, coralline algal foraminiferal biomicrite).

  13. Geologic map of Detrital, Hualapai, and Sacramento Valleys and surrounding areas, northwest Arizona

    USGS Publications Warehouse

    Beard, L. Sue; Kennedy, Jeffrey; Truini, Margot; Felger, Tracey

    2011-01-01

    A 1:250,000-scale geologic map and report covering the Detrital, Hualapai, and Sacramento valleys in northwest Arizona is presented for the purpose of improving understanding of the geology and geohydrology of the basins beneath those valleys. The map was compiled from existing geologic mapping, augmented by digital photogeologic reconnaissance mapping. The most recent geologic map for the area, and the only digital one, is the 1:1,000,000-scale Geologic Map of Arizona. The larger scale map presented here includes significantly more detailed geology than the Geologic Map of Arizona in terms of accuracy of geologic unit contacts, number of faults, fault type, fault location, and details of Neogene and Quaternary deposits. Many sources were used to compile the geology; the accompanying geodatabase includes a source field in the polygon feature class that lists source references for polygon features. The citations for the source field are included in the reference section.

  14. Gravimetric geoid in the Northwest Pacific Ocean

    NASA Technical Reports Server (NTRS)

    Watts, A. B.; Leeds, A. R.

    1977-01-01

    A total of 3708 1 x 1 deg free-air gravity anomaly averages have been used to construct a new 1 x 1 deg gravimetric geoid of the Northwest Pacific Ocean. The 1 x 1 deg averages are based on a compilation of 147,000 surface ship and pendulum gravity measurements. Difference geoid undulations range from a maximum of +19 m over the Hawaiian ridge to a minimum of -31 m over the junction of the Kuril and Aleutian trenches. The Hawaiian swell is associated with a geoidal high of up to +15 m with wavelengths of about 2200 km and the topographic rises seaward of deep-sea trenches are associated with geoidal highs of up to 4 m with wavelengths of about 220-900 km. The agreement between the gravimetric geoid and Skylab-4 and Geos-3 altimeter data is close for wavelengths greater than about 300 km but poor for shorter wavelengths.

  15. Ice thickness in the Northwest Passage

    NASA Astrophysics Data System (ADS)

    Haas, Christian; Howell, Stephen E. L.

    2015-09-01

    Recently, the feasibility of commercial shipping in the ice-prone Northwest Passage (NWP) has attracted a lot of attention. However, very little ice thickness information actually exists. We present results of the first ever airborne electromagnetic ice thickness surveys over the NWP carried out in April and May 2011 and 2015 over first-year and multiyear ice. These show modal thicknesses between 1.8 and 2.0 m in all regions. Mean thicknesses over 3 m and thick, deformed ice were observed over some multiyear ice regimes shown to originate from the Arctic Ocean. Thick ice features more than 100 m wide and thicker than 4 m occurred frequently. Results indicate that even in today's climate, ice conditions must still be considered severe. These results have important implications for the prediction of ice breakup and summer ice conditions, and the assessment of sea ice hazards during the summer shipping season.

  16. Macromoths of northwest forests and woodlands

    USGS Publications Warehouse

    Miller, Jeffrey C.; Hammond, Paul C.

    2000-01-01

    The macromoths are a group of families within the order Lepidoptera. The macromoths in the woodlands and forests of the Pacific Northwest are represented by 1,200 species in 12 families: Arctiidae, Dioptidae, Drepanidae, Epiplemidae, Geometridae, Lasiocampidae, Lymantriidae, Noctuidae, Notodontidae, Saturniidae, Sphingidae, and Thyatiridae. In addition to the macromoths, the Lepidoptera are represented by the butterflies and skippers, and the micromoths. Butterflies possess a knob at the tip of the antennae while the tip of the antennae in skippers is typically hooked. The tip of the antennae in macromoths and micromoths is tapered. The differences between macromoths and micromoths is not literally based on size as the names suggest but rather in details of the female reproductive tract and wing venation. These details are discussed and illustrated in most texts on general entomology (Borror et al. 1989) and in books about Lepidoptera (Covell 1984).

  17. Morphometric sexing of Northwest Atlantic Roseate Terns

    USGS Publications Warehouse

    Palestis, Brian G.; Nisbet, Ian C.T.; Hatch, Jeremy J.; Szczys, Patricia; Spendelow, Jeffrey A.

    2012-01-01

    A difficulty in the study of monomorphic species is the inability of observers to visually distinguish females from males. Based on a sample of 745 known-sex birds nesting at Bird Island, MA, USA, a discriminant function analysis (DFA) was used to sex Roseate Terns (Sterna dougallii) of the Northwest Atlantic population using morphological measurements. DFA using only the total length of the head (including the bill) correctly identified the sex of approximately 86% of the terns, which increased to 88% if both members of a pair were measured. Including additional measurements increased these percentages slightly, to 87% and 90%, respectively. These levels of accuracy are generally higher than those reported for other species of terns. Because female-female pairs are frequent in this population, one cannot assume that the member of a pair with the larger head is a male, and additional discriminant functions were developed to help separate female-female from male-female pairs.

  18. The Eskimos of the Northwest Passage

    PubMed Central

    Davies, L. E. C.; Hanson, S.

    1965-01-01

    In 1959 and 1960, during the annual survey conducted by the Federal Northern Health Services in the area of the Northwest Passage, the diet and living conditions of some 1500 Eskimos who live in this area were studied and blood and urine samples were obtained from 40-50% of this population. Hemoglobin, blood cell morphology, serum protein-bound iodine, serum proteins, serum lipids and serum total cholesterol estimations, urinalyses, and agglutination studies for brucellosis were carried out. Hemoglobin levels were in the normal range; however, increased contact with civilization appeared to be associated with lower hemoglobin levels. Eleven per cent of the Eskimos showed eosinophilia. Serum proteins were normal. Serum lipids and serum cholesterol levels were higher in Eskimo children living in a government residential school than in a comparable group living on the Barren Lands. Serum protein-bound iodine levels were in the upper euthyroid range. Diabetes mellitus occurs among Eskimos. Sporadic cases of brucellosis also occur. PMID:14246293

  19. Using hierarchical models to estimate effects of ocean anomalies on north-west Pacific Chinook salmon Oncorhynchus tshawytscha recruitment.

    PubMed

    Sharma, R; Liermann, M

    2010-11-01

    The high variability in survival over the past three decades of north-west Pacific Chinook salmon Oncorhynchus tshawytscha is summarized for 24 stocks and analysed using hierarchical Bayesian models. Results from a simple model indicate that recruitment anomalies appear to be correlated in time and space. A simple model with a covariate based on basin-scale effects (Pacific Decadal Oscillation and El Niño Southern Oscillation) and local-scale effects (sea surface temperature, SST anomaly) was introduced to explain this variability. The model still exhibited residual patterns that were removed when a random-walk component was added to the model. The analysis indicates that recruitment is negatively related to SST anomaly for all stocks and the effect of basin-scale variables is negligible. The effect of climate over the next century is expected to result in estimated recruitment declining by an average of 13% for O. tshawytscha stocks coastwide.

  20. Devonian shelf basin, Michigan basin, Alpena region

    SciTech Connect

    Gutschick, R.C.

    1986-08-01

    This biostratigraphic study involves the Devonian paleogeography-paleoecology-paleobathymetry of the transition from carbonate platform shelf margin to basinal sedimentation for the northern part of the Michigan basin in the Alpena region. Shelf-basin analysis is based on lithofacies, rock colors, concretion, biostratigraphy, paleoecology of faunas - especially microfaunas and trace fossils - stratified water column, eustasy, and application of Walther's Law. Field observations were made on Partridge Point along Lake Huron, where type sections of the Middle Devonian Thunder Bay Limestone and Late Devonian Squaw Bay Limestone are exposed; and the Antrim black shale at Paxton quarry. The Thunder Bay Limestone evolved as a carbonate platform, subtidal shelf-margin aerobic environment dominated by sessile benthic coralline organisms and shelly fauna, but not reef framework. The Squaw Bay Limestone is transitional shelf to basin, with aspects of slope environment and deeper water off-platform, pelagic organic biostromal molluscan-conodont carbonate deposited during the onset of a stratified water column (dysaerobic benthos-polychaete. agglutinated tubes, sulfides) and pycnocline. The Antrim Shale, in an exceptional black shale exposure in the Paxton quarry, represents deep-water basinal deposition whose bottom waters lacked oxygen. Faunas (conodonts, styliolines, radiolarians) and floras (tasmanitids, calamitids, palynomorphs) are from the aerobic pelagic realm, as indicated from concretions and shale fossil evidence. A benthos is lacking, except for bioturbation from organisms introduced by entrained oxygenated distal turbidite dispersion into the barren bottom black muds. Basinal hydrocarbon source rocks are abundant and updip carbonate reservoirs rim the basin. The Antrim Shale sequence contains the interval of Frasnian-Famennian faunal extinction.