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Sample records for campos basin heranca

  1. Subsidence history and tectonic evolution of Campos basin, offshore Brazil

    SciTech Connect

    Mohriak, W.U.; Karner, G.D.; Dewey, J.F.

    1987-05-01

    The tectonic component of subsidence in the Campos basin reflects different stages of crustal reequilibration subsequent to the stretching that preceded the breakup of Pangea. Concomitant with rifting in the South Atlantic, Neocomian lacustrine rocks, with associated widespread mafic volcanism, were deposited on a vary rapidly subsiding crust. The proto-oceanic stage (Aptian) is marked by a sequence of evaporitic rocks whose originally greater sedimentary thickness is indicated by residual evaporitic layers with abundant salt flow features. An open marine environment begins with thick Albian/Cenomanian limestones that grade upward and basinward into shales. This section, with halokinetic features and listric detached faulting sloping out on salt, is characterized by an increased sedimentation rate. The marine Upper Cretaceous to Recent clastic section, associated with the more quiescent phase of thermal subsidence, is characterized by drastic changes in sedimentation rate. Stratigraphic modeling of the sedimentary facies suggests a flexurally controlled loading mechanism (regional compensation) with a temporally and spatially variable rigidity. Locally, the subsidence in the rift-phase fault-bounded blocks shows no correspondence with the overall thermal subsidence, implying that the crust was not effectively thinned by simple, vertically balanced stretching. Deep reflection seismic sections show a general correspondence between sedimentary isopachs and Moho topography, which broadly compensates for the observed subsidence. However, even the Moho is locally affected by crustal-scale master faults that apparently are also controlling the movement mechanisms during the rift-phase faulting.

  2. Petroleum geology of Campos Basin, Brazil: A successful case history of deep water exploration

    SciTech Connect

    Franke, M.R.; Lugon, H.A.F.; Beraldo, W.L. )

    1990-05-01

    Campos Basin, the most prolific Brazilian basin, produces almost 400,000 bbl of oil per day and contains 70% of the national reserves. The basin is located on the southeastern coast of Brazil, covering a prospectable area of 100,000 km{sup 2} Campos is a passive continental margin basin originated by the breakup of Pangea and the rifting of the South American and African plates in the Early Cretaceous. The basin's sedimentary section encompasses three megasequences: nonmarine, transitional, and marine, ranging in age from Neocomian to Holocene. Hydrocarbon generation is related to nonmarine organic-rich shales and marls, and hydrocarbon entrapment assumes ascendent migration along fault planes and through salt gaps toward reservoirs ranging in age from Neocomian to Tertiary (mainly turbiditic sandstones). The first onshore stratigraphic well was drilled based on gravity surveys in 1958. The acquisition of new geophysical data, mainly seismic reflection data, followed after 1968. The first offshore well was drilled in 1971, and in 1974, the first oil field, Garopua, was discovered. Giant hydrocarbon accumulations have been discovered in water depths ranging from 400 to 1,800 m since 1984. As of mid-1989, 35 offshore oil fields have been discovered, 760 million bbl of oil, and 490 bcf of gas have been produced. The basin oil and equivalent gas reserves are estimated in 6.0 billion bbl, 60% of which is located in the deep-water giant oil fields.

  3. Cheirimedon foscae sp. nov. (Amphipoda: Lysianassidae: Tryphosinae) from the deep sea Campos Basin, Southwestern Atlantic Ocean.

    PubMed

    Siqueira, Silvana Gomes L; Serejo, Cristiana S

    2014-01-01

    A new species of lysianassid amphipod belonging to the genus Cheirimedon was collected on the continental slope of the Campos Basin, the largest oil reserve in Brazilian waters. This is the first record of the genus Cheirimedon from the Atlantic Ocean, which was previously restricted to the Antarctic and Tasmanian sea. The new species is fully illustrated and compared with related species. Additionally, a world key to the Cheirimedon species is provided. 

  4. Diagenetic evolution of Cretaceous-Tertiary turbidite reservoirs, Campos Basin, Brazil

    SciTech Connect

    Moraes, M.A.S.

    1989-05-01

    Three sandstone turbidite sequences of the Campos basin (offshore, state of Rio de Janeiro, Brazil) were petrologically studied: (1) the Albian-Cenomanian Namorado Sandstone on the Macae Formation, (2) the Upper Cretaceous Carapebus Member of the Campos Formation, and (3) the Eocene Carapebus Member of the Campos Formation. The sequences represent deep marine deposits consisting mostly of massive sandstones rather than classical turbidites, indicating sand-rich submarine fans were the main depositional system of these sequences. The framework composition of the sandstones averages for quartz, feldspar, and lithics are Q/sub 60/F/sub 40/L/sub tr/ for the Cretaceous rocks and Q/sub 71/F/sub 29/L/sub tr/ for the Eocene rocks, plotting granitic rock fragments at the feldspar pole. The main diagenetic phases that affected the sandstones studied were (1) development of a clay matrix due to compaction of rip-up mud clasts, (2) partial replacement of the matrix by opal, (3) precipitation of small pyrite framboids, (4) widespread direct precipitation or replacement of different materials by calcite, (5) intense generation of secondary porosity, (6) localized kaolinite development, (7) minor precipitation of quartz and feldspar overgrowths, (8) development of dolomite, ferroan dolomite, and ankerite, and (9) replacement of different materials with minor direct precipitation of late pyrite. Geologic and geochemical evidence lets them infer the main processes that controlled diagenetic transformations and mass transfer within the sequence studied. The principal source of carbonate cements was pressure solution of the underlying Macae Formation. Most of the diagenetic evolution of the sandstones was apparently controlled by the relative balance between the activity of CO/sub 2/ and carboxylic acid species in the formation waters, both related to organic matter transformations within adjacent marine shales.

  5. The Alegre Lineament and its role over the tectonic evolution of the Campos Basin and adjacent continental margin, Southeastern Brazil

    NASA Astrophysics Data System (ADS)

    Calegari, Salomão Silva; Neves, Mirna Aparecida; Guadagnin, Felipe; França, George Sand; Vincentelli, Maria Gabriela Castillo

    2016-08-01

    The structural framework and tectonic evolution of the sedimentary basins along the eastern margin of the South American continent are closely associated with the tectonic framework and crustal heterogeneities inherited from the Precambrian basement. However, the role of NW-SE and NNW-SSE structures observed at the outcropping basement in Southeastern Brazil and its impact over the development of those basins have not been closely investigated. In the continental region adjacent to the Campos Basin, we described a geological feature with NNW-SSE orientation, named in this paper as the Alegre Fracture Zone (AFZ), which is observed in the onshore basement and can be projected to the offshore basin. The main goal of this work was to study this structural lineament and its influence on the tectonic evolution of the central portion of the Campos Basin and adjacent mainland. The onshore area was investigated through remote sensing data joint with field observations, and the offshore area was studied through the interpretation of 2-D seismic data calibrated by geophysical well logs. We concluded that the AFZ occurs in both onshore and offshore as a brittle deformation zone formed by multiple sets of fractures that originated in the Cambrian and were reactivated mainly as normal faults during the rift phase and in the Cenozoic. In the Campos Basin, the AFZ delimitates the western side of the Corvina-Parati Low, composing a complex fault system with the NE-SW faults and the NW-SE transfer faults.

  6. Nephtyidae (Annelida: Polychaeta) from the Campos Basin, including two new species and a new record.

    PubMed

    Franco, Natália Bizzo; Rizzo, Alexandra E

    2016-05-24

    Members of the marine polychaete family Nephtyidae are commonly found in soft substrates. Their most distinctive characteristic is the presence of interramal branchiae located between the notopodia and neuropodia. In the present study, five species of Nephtyidae: Aglaophamus fabrun sp. nov., Aglaophamus juvenalis (Kinberg, 1866), Inermonephtys inermis (Ehlers, 1887), Inermonephtys soldius sp. nov. and Nephtys squamosa Ehlers, 1887 were found in the Campos Basin, state of Rio de Janeiro, including two new species and a new record for the Brazilian coast. Aglaophamus fabrun sp. nov. has a proboscis with 10 pairs of distal papillae and approximately 20 subdistal papillae in rows, with 3-5 papillae in each row; and lacks an unpaired median papilla; the prostomium has a pair of eyes and a characteristic pigmentation pattern. Inermonephtys soldius sp. nov. has interramal branchiae starting from parapodium 5, and basal papillae starting on chaetiger 6. Inermonephtys inermis is a new record for the Brazilian coast. Descriptions, comments and a key to species of Nephtyidae recorded from Brazil are provided.

  7. [Work-related accidents on oil drilling platforms in the Campos Basin, Rio de Janeiro, Brazil].

    PubMed

    Freitas, C M; Souza, C A; Machado, J M; Porto, M F

    2001-01-01

    The offshore oil industry is characterized by complex systems in relation to technology and organization of work. Working conditions are hazardous, resulting in accidents and even occasional full-scale catastrophes. This article is the result of a study on work-related accidents in the offshore platforms in the Campos Basin, Rio de Janeiro State. The primary objective was to provide technical back-up for both workers' representative organizations and public authorities. As a methodology, we attempt to go beyond the immediate causes of accidents and emphasize underlying causes related to organizational and managerial aspects. The sources were used in such a way as to permit classification in relation to the type of incident, technological system, operation, and immediate and underlying causes. The results show the aggravation of safety conditions and the immediate need for public authorities and the offshore oil industry in Brazil to change the methods used to investigate accidents in order to identify the main causes in the organizational and managerial structure of companies.

  8. Nephtyidae (Annelida: Polychaeta) from the Campos Basin, including two new species and a new record.

    PubMed

    Franco, Natália Bizzo; Rizzo, Alexandra E

    2016-01-01

    Members of the marine polychaete family Nephtyidae are commonly found in soft substrates. Their most distinctive characteristic is the presence of interramal branchiae located between the notopodia and neuropodia. In the present study, five species of Nephtyidae: Aglaophamus fabrun sp. nov., Aglaophamus juvenalis (Kinberg, 1866), Inermonephtys inermis (Ehlers, 1887), Inermonephtys soldius sp. nov. and Nephtys squamosa Ehlers, 1887 were found in the Campos Basin, state of Rio de Janeiro, including two new species and a new record for the Brazilian coast. Aglaophamus fabrun sp. nov. has a proboscis with 10 pairs of distal papillae and approximately 20 subdistal papillae in rows, with 3-5 papillae in each row; and lacks an unpaired median papilla; the prostomium has a pair of eyes and a characteristic pigmentation pattern. Inermonephtys soldius sp. nov. has interramal branchiae starting from parapodium 5, and basal papillae starting on chaetiger 6. Inermonephtys inermis is a new record for the Brazilian coast. Descriptions, comments and a key to species of Nephtyidae recorded from Brazil are provided. PMID:27395131

  9. [Work-related accidents on oil drilling platforms in the Campos Basin, Rio de Janeiro, Brazil].

    PubMed

    Freitas, C M; Souza, C A; Machado, J M; Porto, M F

    2001-01-01

    The offshore oil industry is characterized by complex systems in relation to technology and organization of work. Working conditions are hazardous, resulting in accidents and even occasional full-scale catastrophes. This article is the result of a study on work-related accidents in the offshore platforms in the Campos Basin, Rio de Janeiro State. The primary objective was to provide technical back-up for both workers' representative organizations and public authorities. As a methodology, we attempt to go beyond the immediate causes of accidents and emphasize underlying causes related to organizational and managerial aspects. The sources were used in such a way as to permit classification in relation to the type of incident, technological system, operation, and immediate and underlying causes. The results show the aggravation of safety conditions and the immediate need for public authorities and the offshore oil industry in Brazil to change the methods used to investigate accidents in order to identify the main causes in the organizational and managerial structure of companies. PMID:11241934

  10. The family Caprellidae (Amphipoda: Caprelloidea: Caprellidae) from Campos Basin, Southwestern Atlantic, with a key of species occurring in Brazil.

    PubMed

    Mauro, Fábio Da Motta; Serejo, Cristiana Silveira

    2015-08-21

    Caprellid material of the present study was collected between 25-3000 m depth from the Campos Basin area, Southwestern Atlantic. As a result, Deutella incerta was found as a new record to the Southwestern Atlantic and two new species are described: Liropus guerragarciai sp. nov. and Mayerella sittropiae sp. nov. Besides, Paracaprella pusilla is herein redescribed as a common component of the Campos Basin amphipod community. Caprellids are a diverse and abundant group that can be found among algae and general biological substrates of the continental shelf area. As more deep sea samples are coming into light, they are turning out to be also a common component in this habitat. Including the present data, there are 25 caprellid species recorded in Brazil, being four of them restricted to the slope areas and 14 endemic to the Brazilian coast. A key to the Caprellidae species from Brazil is provided.

  11. The family Caprellidae (Amphipoda: Caprelloidea: Caprellidae) from Campos Basin, Southwestern Atlantic, with a key of species occurring in Brazil.

    PubMed

    Mauro, Fábio Da Motta; Serejo, Cristiana Silveira

    2015-01-01

    Caprellid material of the present study was collected between 25-3000 m depth from the Campos Basin area, Southwestern Atlantic. As a result, Deutella incerta was found as a new record to the Southwestern Atlantic and two new species are described: Liropus guerragarciai sp. nov. and Mayerella sittropiae sp. nov. Besides, Paracaprella pusilla is herein redescribed as a common component of the Campos Basin amphipod community. Caprellids are a diverse and abundant group that can be found among algae and general biological substrates of the continental shelf area. As more deep sea samples are coming into light, they are turning out to be also a common component in this habitat. Including the present data, there are 25 caprellid species recorded in Brazil, being four of them restricted to the slope areas and 14 endemic to the Brazilian coast. A key to the Caprellidae species from Brazil is provided. PMID:26623760

  12. Application of MSS/LANDSAT images to the structural study of recent sedimentary areas: Campos Sedimentary Basin, Rio de Janeiro, Brazil

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Barbosa, M. P.

    1983-01-01

    Visual and computer aided interpretation of MSS/LANDSAT data identified linear and circular features which represent the ""reflexes'' of the crystalline basement structures in the Cenozoic sediments of the emergent part of the Campos Sedimentary Basin.

  13. Influence of urban area on the water quality of the Campo River basin, Paraná State, Brazil.

    PubMed

    Carvalho, K Q; Lima, S B; Passig, F H; Gusmão, L K; Souza, D C; Kreutz, C; Belini, A D; Arantes, E J

    2015-12-01

    The Campo River basin is located on the third plateau of the Paraná State or trap plateau of Paraná, at the middle portion between the rivers Ivaí and Piquiri, southern Brazil, between the coordinates 23° 53 and 24° 10' South Latitude and 52° 15' and 52° 31' West Longitude. The basin has 384 Km² area, being 247 km² in the municipality of Campo Mourão and 137 km² in the municipality of Peabiru, in Paraná State. The Campo River is a left bank tributary of the Mourão River, which flows into the Ivaí River. The objective of this study was to monitor water quality in the Km 119 River and the Campo River, tributaries of the Mourão River, with monthly collection of water samples to determine pH, temperature, turbidity, biochemical oxygen demand, dissolved oxygen, fecal coliforms, total solids, total nitrogen, ammoniacal nitrogen, nitrite, nitrate and total phosphorus. The results obtained were compared with the indices established by the environmental legislation and applied in the determination of the Water Quality Index (WQI) used by the Water Institute of Paraná State, regulating environmental agency. Poor water quality in these rivers presents a worrying scenario for the region, since this river is the main source of water supply for the public system. Results of organic matter, fecal coliforms and total phosphorus were higher than the limits established by Resolution CONAMA 357/2005 to river class 2, specially at downstream of the Km 119 River and the Campo River, due to the significant influence of the urban anthropic activity by the lack of tertiary treatment and also rural by the lack of basic sanitation in this area. Results of WQI of Km 119 River and do Campo River indicated that water quality can be classified as average in 71% and good in 29% of the sites evaluated.

  14. Influence of urban area on the water quality of the Campo River basin, Paraná State, Brazil.

    PubMed

    Carvalho, K Q; Lima, S B; Passig, F H; Gusmão, L K; Souza, D C; Kreutz, C; Belini, A D; Arantes, E J

    2015-12-01

    The Campo River basin is located on the third plateau of the Paraná State or trap plateau of Paraná, at the middle portion between the rivers Ivaí and Piquiri, southern Brazil, between the coordinates 23° 53 and 24° 10' South Latitude and 52° 15' and 52° 31' West Longitude. The basin has 384 Km² area, being 247 km² in the municipality of Campo Mourão and 137 km² in the municipality of Peabiru, in Paraná State. The Campo River is a left bank tributary of the Mourão River, which flows into the Ivaí River. The objective of this study was to monitor water quality in the Km 119 River and the Campo River, tributaries of the Mourão River, with monthly collection of water samples to determine pH, temperature, turbidity, biochemical oxygen demand, dissolved oxygen, fecal coliforms, total solids, total nitrogen, ammoniacal nitrogen, nitrite, nitrate and total phosphorus. The results obtained were compared with the indices established by the environmental legislation and applied in the determination of the Water Quality Index (WQI) used by the Water Institute of Paraná State, regulating environmental agency. Poor water quality in these rivers presents a worrying scenario for the region, since this river is the main source of water supply for the public system. Results of organic matter, fecal coliforms and total phosphorus were higher than the limits established by Resolution CONAMA 357/2005 to river class 2, specially at downstream of the Km 119 River and the Campo River, due to the significant influence of the urban anthropic activity by the lack of tertiary treatment and also rural by the lack of basic sanitation in this area. Results of WQI of Km 119 River and do Campo River indicated that water quality can be classified as average in 71% and good in 29% of the sites evaluated. PMID:26628235

  15. Mercury in sediments from shelf and continental slope at Campos Basin near Rio de Janeiro, Brazil

    NASA Astrophysics Data System (ADS)

    Araujo, Beatriz; Hintelmann, Holger; Dimock, Brian; Gomes de Almeida, Marcelo; Falcão, Ana Paula; de Rezende, Carlos Eduardo

    2016-04-01

    Mercury (Hg) is a global pollutant due to its ability to undergo long-range transport from source regions to remote parts of the world, and its ubiquitous presence in aquatic ecosystems. The Hg isotope ratios could be an effective tool for tracing the sources and process of Hg in the environment. This study aimed to establish the distribution of mercury in surface sediments of three transects (25- 3000m water depth) in continental shelf and slope in Campos Basin-RJ-Brazil, using the Hg isotopes to understand the geochemical processes relating to Hg cycling that occur in a subtropical coastal environment. The study area was divided into three transects: A (located to the south and close to a upwelling area), D (located opposite the mouth of the Paraiba do Sul River) and I (located north near the top of Vitória-ES). Sampling isobaths were 25, 50, 75, 100, 150, 400, 700, 1000, 1300, 1900, 2500 and 3000m. The Total Hg, MMHg and Hg stable isotopes were determined based on EPA Method 1631, EPA method 1630 and Foucher and Hintelmann (2006), respectively. The silt/clay ranged from 0.05 to 95%, and the organic carbon (OC) from 0.07 to 1.43 % for all transects. THg and MMHg concentrations in the shelf were 11.9 ± 7.2 (1.7- 22.2) ng.g‑1 and 0.15 ± 0.12 (0.02 - 0.40) ng.g‑1; in the slope 30.3 ± 9.2 (11.6 - 51.6) ng.g‑1 and 0.13 ± 0.06 (0.03 -0.29) ng.g‑1 , respectively. The δ202Hg and Δ199Hg varied from -0.32 to -1.85 ‰ (-0.79 ± 0.44‰) and -0.41 to 0.09 ‰ (-0.03 ± 0.12 ‰) for all transects, respectively. The delta values between both regions are significantly different, the shelf region showed δ202Hg from -0.59 to -2.19 ‰ (mean: -1.52 ±0.65) and Δ199Hg from - 0.53 to 0.08 ‰ (mean: -0.27 ±0.55) and the slope region were observed δ202Hg values from -0.32 to -1.82 ‰ (mean: -0.73 ±0.39 ‰ n=18) and gΔ199Hg from -0.23 to 0.09‰ (mean: -0.02 ±0.08‰ n=5). The slope appears to be enriched with heavier isotopes compared to the shelf, however

  16. Mercury in sediments from shelf and continental slope at Campos Basin near Rio de Janeiro, Brazil

    NASA Astrophysics Data System (ADS)

    Araujo, Beatriz; Hintelmann, Holger; Dimock, Brian; Gomes de Almeida, Marcelo; Falcão, Ana Paula; de Rezende, Carlos Eduardo

    2016-04-01

    Mercury (Hg) is a global pollutant due to its ability to undergo long-range transport from source regions to remote parts of the world, and its ubiquitous presence in aquatic ecosystems. The Hg isotope ratios could be an effective tool for tracing the sources and process of Hg in the environment. This study aimed to establish the distribution of mercury in surface sediments of three transects (25- 3000m water depth) in continental shelf and slope in Campos Basin-RJ-Brazil, using the Hg isotopes to understand the geochemical processes relating to Hg cycling that occur in a subtropical coastal environment. The study area was divided into three transects: A (located to the south and close to a upwelling area), D (located opposite the mouth of the Paraiba do Sul River) and I (located north near the top of Vitória-ES). Sampling isobaths were 25, 50, 75, 100, 150, 400, 700, 1000, 1300, 1900, 2500 and 3000m. The Total Hg, MMHg and Hg stable isotopes were determined based on EPA Method 1631, EPA method 1630 and Foucher and Hintelmann (2006), respectively. The silt/clay ranged from 0.05 to 95%, and the organic carbon (OC) from 0.07 to 1.43 % for all transects. THg and MMHg concentrations in the shelf were 11.9 ± 7.2 (1.7- 22.2) ng.g-1 and 0.15 ± 0.12 (0.02 - 0.40) ng.g-1; in the slope 30.3 ± 9.2 (11.6 - 51.6) ng.g-1 and 0.13 ± 0.06 (0.03 -0.29) ng.g-1 , respectively. The δ202Hg and Δ199Hg varied from -0.32 to -1.85 ‰ (-0.79 ± 0.44‰) and -0.41 to 0.09 ‰ (-0.03 ± 0.12 ‰) for all transects, respectively. The delta values between both regions are significantly different, the shelf region showed δ202Hg from -0.59 to -2.19 ‰ (mean: -1.52 ±0.65) and Δ199Hg from - 0.53 to 0.08 ‰ (mean: -0.27 ±0.55) and the slope region were observed δ202Hg values from -0.32 to -1.82 ‰ (mean: -0.73 ±0.39 ‰ n=18) and gΔ199Hg from -0.23 to 0.09‰ (mean: -0.02 ±0.08‰ n=5). The slope appears to be enriched with heavier isotopes compared to the shelf, however, in the

  17. Shelf-fed turbidite system model and its application to the Oligocene deposits of the Campos Basin, Brazil

    SciTech Connect

    Peres, W.E. )

    1993-01-01

    Despite the large number of models involving the genesis and sedimentary facies of deep-water sandstones, none of these models adequately explain the origin and evolution of the extremely clean, widespread (over 6000 km[sup 2]), predominantly massive, thick (over 150 m), blanket-like sandstones deposited in the deep-water environment of the Campos Basin during the Oligocene. Consequently, to explain this sandstone, the author proposes a shelf-fed turbidite system model, which is strongly based on the Campos Basin data set. The basic framework necessary for the development of a shelf-fed turbidite system includes (1) deposition of a large volume of clastics during the buildup of a shelf-sand-rich unit, which later constitutes the main source of sediment for the system, (2) localized tectonic pulses that modify the outer shelf declivity and trigger mass flows; and (3) a relative fall of sea level, which causes the subaqueous exposure of the shelf sediments to reworking in a shallow, high-energy marine environment. These three basic elements are equally important for shelf-fed turbidity system development, but relative sea level position controls the development of the progradational, aggradational, and retrogradational depositional phases within the system. Submarine canyons commonly are scoured during all three phases on the outer shelf and lower slope environments. The shelf-fed turbidite system model may apply to other sedimentary basins, principally to those of the Atlantic-continental margins that have a thick evaporite sublayer. Halokinesis can provide the necessary room for the shelf sedimentary-unit buildup, the tectonic pulses that trigger the flows, and even localized relative sea level oscillations that can accelerate or abort any one of the depositional phases of the system. 25 refs., 26 figs.

  18. Sedimentology and sequence stratigraphy from outcrops of the Kribi-Campo sub-basin: Lower Mundeck Formation (Lower Cretaceous, southern Cameroon)

    NASA Astrophysics Data System (ADS)

    Ntamak-Nida, Marie Joseph; Bourquin, Sylvie; Makong, Jean-Claude; Baudin, François; Mpesse, Jean Engelbert; Ngouem, Christophe Itjoko; Komguem, Paul Bertrand; Abolo, Guy Martin

    2010-08-01

    The Kribi-Campo sub-basin is composed of an Early to Mid Cretaceous series from West Africa's Atlantic coast and is located in southern Cameroon in the Central African equatorial rain forest. It is the smallest coastal basin in Cameroon and forms the southern part of the Douala/Kribi-Campo basin known as Douala basin ( s.l.). Until now, no detailed sedimentological studies have been carried out on the outcrops of this basin located in the Campo area. The aim of this study was to characterise the depositional environments, vertical evolution and tectonic context of these Lower Cretaceous series in order to make a comparison with adjacent basins and replace them in the geodynamic context. Facies analysis of the Lower Mundeck Formation (Lower Cretaceous) indicates the presence of four major, interfigered facies associations, that are inferred to represent elements of an alluvial to lacustrine-fan delta system. The clast lithologies suggest proximity of relief supplying coarse-grained sediment during the deposition of the Lower Mundeck Formation at Campo. The general dip and direction of the bedding is approximately 10°-12°NW, which also corresponds to the orientation of the foliations in the underlying metamorphic basement. The main sedimentary succession is characterised by a major retrogradational/progradational cycle of Late Aptian age, evaluated at about 3 Ma, with a well-developed progradational trend characterised by fluctuations of the recognised depositional environments. Fluctuations in lake level and sediment supply were possibly controlled by active faults at the basin margin, although climatic changes may have also played a role. The consistently W-WNW palaeoflow of sediments suggests that the palaeorelief was located to the east and could be oriented in a NNE-SSW direction, downthrown to the west. Local outcrops dated as Albian, both north and south of the main outcrop, display some marine influence. These deposits are cut by 040-060 faults parallel to

  19. Well-log signatures of alluvial-lacustrine reservoirs and source rocks, Lagoa-Feia Formations, Lower Cretaceous, Campos Basin, offshore Brazil

    SciTech Connect

    Abrahao, D.; Warme, J.E.

    1988-01-01

    The Campos basin is situated in offshore southeastern Brazil. The Lagoa Feia is the basal formation in the stratigraphic sequence of the basin, and was deposited during rifting in an evolving complex of lakes of different sizes and chemical characteristics, overlying and closely associated with rift volcanism. The stratigraphic sequence is dominated by lacustrine limestones and shales (some of them organic-rich), and volcaniclastic conglomerates deposited on alluvial fans. The sequence is capped by marine evaporites. In the Lagoa Feia Formation, complex lithologies make reservoirs and source rocks unsuitable for conventional well-log interpretation. To solve this problem, cores were studied and the observed characteristics related to log responses. The results have been extended through the entire basin for other wells where those facies were not cored. The reservoir facies in the Lagoa Feia Formation are restricted to levels of pure pelecypod shells (''coquinas''). Resistivity, sonic, neutron, density, and gamma-ray logs were used in this work to show how petrophysical properties are derived for the unconventional reservoirs existing in this formation. The same suite of logs was used to develop methods to define geochemical characteristics where source rock data are sparse in the organic-rich lacustrine shales of the Lagoa Feia Formation. These shales are the main source rocks for all the oil discovered to date in the Campos basin.

  20. Major controlling factors on hydrocarbon generation and leakage in South Atlantic conjugate margins: A comparative study of Colorado, Orange, Campos and Lower Congo basins

    NASA Astrophysics Data System (ADS)

    Marcano, Gabriela; Anka, Zahie; di Primio, Rolando

    2013-09-01

    We present a supra-regional comparative study of the major internal and external factors controlling source rock (SR) maturation and hydrocarbon (HC) generation and leakage in two pairs of conjugate margins across the South Atlantic: the Brazil (Campos Basin)-Angola (Lower Congo Basin) margins located in the "central segment", and the Argentina (Colorado Basin)-South Africa (Orange Basin) in the "southern segment". Our approach is based on the analysis and integration of borehole data, 1D numerical modeling, 2D seismic reflection data, and published reports. Coupling of modeling results, sedimentation rate calculation and seal-bypass system analysis reveal that: (1) oil window is reached by syn-rift SRs in the southern segment during the Early to Late Cretaceous when thermal subsidence is still active, while in the central segment they reach it in Late-Cretaceous-Neogene during a salt remobilization phase, and (2) early HC generation from post-rift SRs in the southern segment and from all SRs in the central segment appears to be controlled mainly by episodes of increased sedimentation rates. The latter seems to be associated with the Andes uplift history for the western South Atlantic basins (Campos and Colorado) and to a possibly climate-driven response for the eastern South Atlantic basins (Orange and Lower Congo). Additionally, we observe that the effect of volcanism on SR maturation in the southern segment is very local. The comparison of Cretaceous mass transport deposit (MTD) episodes with HC peak of generation and paleo-leakage indicators in the southern segment revealed the possible causal effect that HC generation and leakage have over MTD development. Interestingly, Paleogene leakage indicators, which were identified in the Argentina-South Africa conjugate margins, occur contemporaneously to low sedimentation rate periods. Nonetheless, present-day leakage indicators which were also identified in both pairs of conjugate margins might be related to seal

  1. 226Ra, 228Ra and 228Th in scale and sludge samples from the Campos Basin oilfield E&P activities.

    PubMed

    Matta, L E; Godoy, J M; Reis, M C

    2002-01-01

    More than 40 scale and sludge samples from the Campos Basin oilfield were analysed in terms of 226Ra, 228Ra and 228Th. Although the exact origin of the samples was not known, scale samples derived from production pipes and sludge samples from water-oil separation units. Reported values ranged from 0.13 to 331 kBq.kg(-1) for 226Ra, from 0.10 to 245 kBq.kg(-1) for 228Ra and <0.10 to 272 kBq.kg(-1) for 228Th in sludge samples. The concentrations in scales were much more regular than in sludges and ranged from 16.2 to 93.2 kBq.kg(-1) for 226Ra, from 4.0 to 36.9 kBq.kg(-1) for 228Ra and from 4.5 to 18.5 kBq.kg(-1) for 228Th. Based on the Basic Safety Standards recommendations and on the derived results, these activities cannot be regarded as exempted and specific procedures should be designed for their radiological control.

  2. Hamacantha (Hamacantha) boomerang sp. nov. from deep-sea coral mounds at Campos Basin, SW Atlantic, and redescription of H. (H.) schmidtii (Carter, 1882) (Hamacanthidae, Poecilosclerida, Demospongiae).

    PubMed

    Hajdu, Eduardo; Castello-Branco, Cristiana

    2014-01-01

    There are 22 species of Hamacantha registered from all over the world, and frequently from deep-waters, only two of which had previously been reported from the SW Atlantic. Here we describe a third species for this area, Hamacantha (H.) boomerang sp. nov., collected from deep-sea coral mounds at Campos Basin (off Rio de Janeiro state). We found oxeas 271-630 µm long, diancistras in three size classes, 125-155, 45-69 and 20-29 µm, and toxas, 58-82 µm. This is the only Hamacantha combining oxeas and toxas, but the latter are very rare. The species approaches the Caribbean H. (H.) schmidtii (Carter, 1882), where we observed oxeas 390-495 µm long, and diancistras in three size classes, 109-124,  44-54 and 26-41 μm, however toxas appear to be absent. Both species are clearly distinct by micrometric values, as well as the overall morphology of the smaller diancistras, distinct from the intermediate category in the new species, but quite similar in H. (H.) schmidtii. Hamacantha (Vomerula) falcula approaches the new species very closely in microsclere dimensions and morphology, but is set apart by its styloid and smaller megascleres.

  3. Effects of non-aqueous fluids-associated drill cuttings discharge on shelf break macrobenthic communities in the Campos Basin, Brazil.

    PubMed

    Santos, Maria Fernanda L; Silva, Janete; Fachel, Jandyra M G; Pulgati, Fernando H

    2010-08-01

    This paper assesses the effects of non-aqueous fluids (NAF)-associated drill cuttings discharge on shelf break macrobenthic communities in the Campos Basin, off the southeast Brazilian coast, Rio de Janeiro State. Samples were taken with a 0.25-m2 box corer from surrounding two oil and gas wells on three monitoring cruises: before drilling, three months after drilling, and 22 months after drilling. Statistical methodologies used Bayesian geostatistical and analysis of variance models to evaluate the effects of the NAF-associated drill cuttings discharge and to define the impact area. The results indicated that marked variations were not observed in the number of families between cruises, though there were changes in the fauna composition. The changes seen in biological descriptors in both control and background situation areas were not considered significant, showing a temporal homogeneity in means. The impact area presented changes in biological descriptors of communities and trophic structure during the three cruises and such changes were correlated to chemical and physical variables related to the drilling activities, as a result of the mix of drill cuttings and sediment and the anoxic conditions established in the substrate. In that area, three months after drilling, a decrease in diversity and an increase in density, motile deposit-feeders and Pol/Crp ratio, and dominance of opportunistic organisms, such as the capitellid Capitella sp., were observed and, 22 months after drilling, an increase of diversity, reduction of dominance of capitellid polychaete, changes in the fauna composition, and a dominance of opportunistic burrowing and tube-building organisms were observed, indicating an ecological succession process. PMID:20524059

  4. The effect of an oil drilling operation on the trace metal concentrations in offshore bottom sediments of the Campos Basin oil field, SE Brazil.

    PubMed

    Rezende, C E; Lacerda, L D; Ovalle, A R C; Souza, C M M; Gobo, A A R; Santos, D O

    2002-07-01

    The concentrations of Al, Fe, Mn, Zn, Cu, Pb, Ni, Cr, Ba, V, Sn and As in offshore bottom sediments from the Bacia de Campos oil field, SE Brazil, were measured at the beginning and at 7 months after completion of the drilling operation. Concentrations of Al, Fe, Ba, Cr, Ni and Zn were significantly higher closer to the drilling site compared to stations far from the site. Average concentrations of Al, Cu, and in particular of Ni, were significantly higher at the end of the drilling operation than at the beginning. Comparison between drilling area sediments with control sediments of the continental platform, however, showed no significant difference in trace metal concentrations. Under the operation conditions of this drilling event, the results show that while changes in some trace metal concentrations do occur during drilling operations, they are not significantly large to be distinguished from natural variability of the local background concentrations.

  5. The effect of an oil drilling operation on the trace metal concentrations in offshore bottom sediments of the Campos Basin oil field, SE Brazil.

    PubMed

    Rezende, C E; Lacerda, L D; Ovalle, A R C; Souza, C M M; Gobo, A A R; Santos, D O

    2002-07-01

    The concentrations of Al, Fe, Mn, Zn, Cu, Pb, Ni, Cr, Ba, V, Sn and As in offshore bottom sediments from the Bacia de Campos oil field, SE Brazil, were measured at the beginning and at 7 months after completion of the drilling operation. Concentrations of Al, Fe, Ba, Cr, Ni and Zn were significantly higher closer to the drilling site compared to stations far from the site. Average concentrations of Al, Cu, and in particular of Ni, were significantly higher at the end of the drilling operation than at the beginning. Comparison between drilling area sediments with control sediments of the continental platform, however, showed no significant difference in trace metal concentrations. Under the operation conditions of this drilling event, the results show that while changes in some trace metal concentrations do occur during drilling operations, they are not significantly large to be distinguished from natural variability of the local background concentrations. PMID:12222892

  6. Campo de velocidade peculiar na teoria linear

    NASA Astrophysics Data System (ADS)

    Pires, N.

    2003-08-01

    Aglomerados e superaglomerados de galáxias são responsáveis pela chamada velocidade peculiar (movimentos relativos à expansão pura do universo) das galáxias. A amplitude destas perturbações depende da densidade de matéria do universo e do contraste de densidade no interior do volume onde está localizada a galáxia. Em 1980, Peebles introduziu o fator "f", que relaciona a amplitude das perturbações da velocidade com o campo gravitacional peculiar, no contexto da teoria linear. No presente trabalho obtemos uma solução geral analítica para o fator "f" de Peebles do campo de velocidades peculiares, em termos de funções hipergeométricas, válida para qualquer geometria do universo. Como um teste de nossa solução, os resultados encontrados originalmente por Peebles em 1980 e os resultados mais gerais encontrados por O. Lahav e colaboradores em 1991, são reobtidos.

  7. "Ask Argonne" - Edwin Campos, Research Meteorologist, Part 2

    SciTech Connect

    Edwin Campos

    2013-05-23

    Argonne's Edwin Campos has for the last two decades studied weather, and in particular, clouds. His research can help make solar power a more viable option for the U.S. and the world. In this video, Dr. Campos answers questions that were submitted by the public in response to his introductory video: http://www.youtube.com/watch?v=pfdoHz.... We will be posting a new "Ask Argonne" video every other month, on various topics. Keep an eye out for your next opportunity to submit a question and see if it gets answered - and if you get a shout-out on camera.

  8. "Ask Argonne" - Edwin Campos, Research Meteorologist, Part 2

    ScienceCinema

    Edwin Campos

    2016-07-12

    Argonne's Edwin Campos has for the last two decades studied weather, and in particular, clouds. His research can help make solar power a more viable option for the U.S. and the world. In this video, Dr. Campos answers questions that were submitted by the public in response to his introductory video: http://www.youtube.com/watch?v=pfdoHz.... We will be posting a new "Ask Argonne" video every other month, on various topics. Keep an eye out for your next opportunity to submit a question and see if it gets answered - and if you get a shout-out on camera.

  9. Cosmogenic Radionuclides in the Campo Del Cielo Iron Meteorite

    NASA Technical Reports Server (NTRS)

    Liberman, R. G.; FernandezNiello, J. O.; Reedy, R. C.; Fifield, L. K.; diTada, M. L.

    2001-01-01

    Cosmogenic Be-10, Al-26, Cl-36, Ca-41, and Ni-59 were measured in the Campo del Cielo iron meteorite. Our results led us to conclude that the pre-atmospheric radius might have been approximately 2 m. Comparisons with other big bodies are also presented. Additional information is contained in the original extended abstract.

  10. Colonial Memory and the Crime of Rhetoric: Pedro Albizu Campos

    ERIC Educational Resources Information Center

    Villanueva, Victor

    2009-01-01

    Dr. Albizu Campos was a Harvard-educated Puerto Rican politician who was sentenced to eighty years of imprisonment for what he said--sedition. He was called "el Maestro," a powerful speaker, with thousands gathering to listen to his deliberative rhetoric for freedom. He urged the people to reclaim their cultural history and national symbols, like…

  11. The Periodogram Analysis of El Campo Solar Radar Observational Data

    NASA Astrophysics Data System (ADS)

    Ye, L.; Qu, Z. N.; Wang, M.; Gao, G. N.; Lin, J.; Duan, Z. C.

    2015-11-01

    Solar Radar can transmit radar waves to the Sun actively. By analyzing the echoes, we can obtain motions, magnetic field, and other information of solar atmosphere. The El Campo solar radar has done regular observations on solar corona for 8 years from 1961 to 1969, which tracked solar activities during a long time. We analyzed El Campo data with the Lomb-Scargle periodogram algorithm, and found that there are periods of 200~days and~540~days in the variations of the solar radar cross sections. Compared radar cross sections with the Dst indexes, we found that there was no significant relationship between them. Then, the proposal of solar radar in future was made.

  12. Helping enhances productivity in campo flicker ( Colaptes campestris) cooperative groups

    NASA Astrophysics Data System (ADS)

    Dias, Raphael Igor; Webster, Michael S.; Macedo, Regina H.

    2015-06-01

    Reproductive adults in many bird species are assisted by non-breeding auxiliary helpers at the nest, yet the impact of auxiliaries on reproduction is variable and not always obvious. In this study, we tested Hamilton's rule and evaluated the effect of auxiliaries on productivity in the facultative cooperative breeder campo flicker ( Colaptes campestris campestris). Campo flickers have a variable mating system, with some groups having auxiliaries and others lacking them (i.e., unassisted pairs). Most auxiliaries are closely related to the breeding pair (primary auxiliaries), but some auxiliaries (secondary auxiliaries) are unrelated females that joined established groups. We found no effect of breeder quality (body condition) or territory quality (food availability) on group productivity, but the presence of auxiliaries increased the number of fledglings produced relative to unassisted pairs. Nonetheless, the indirect benefit of helping was small and did not outweigh the costs of delayed breeding and so seemed insufficient to explain the evolution of cooperative breeding in campo flickers. We concluded that some ecological constraints must limit dispersal or independent breeding, making staying in the group a "best-of-a-bad-job" situation for auxiliaries.

  13. Circumscribing campo rupestre - megadiverse Brazilian rocky montane savanas.

    PubMed

    Alves, R J V; Silva, N G; Oliveira, J A; Medeiros, D

    2014-05-01

    Currently campo rupestre (CR) is a name accepted and used internationally by botanists, zoologists, and other naturalists, usually applied to a very specific ecosystem, despite the lack of a consensual published circumscription. We present a tentative geographic circumscription of the term, combining data on climate, geology, geomorphology, soil, flora, fauna and vegetation. The circumscription of campo rupestre proposed herein is based on the following premises: (1) the classification of vegetation is not an exact science, and it is difficult to attain a high degree of consensus to the circumscription of vegetation names; (2) despite this, vegetation classification is useful for conservation and management. It is thus desirable to circumscribe vegetation types with the greatest attainable precision; (3) there is a need to preserve all montane and rocky vegetation types, regardless of classification, biome, etc; (4) the CRs are formed by a complex mosaic of vegetation types including rock-dwelling, psammophilous, aquatic, epiphytic, and penumbral plant communities. Campos rupestres stricto sensu are a Neotropical, azonal vegetation complex endemic to Brazil, forming a mosaic of rocky mountaintop "archipelagos" inserted within a matrix of zonal vegetation, mainly in the Cerrado and Caatinga provinces of the Brazilian Shield (southeastern, northeastern and central-western regions), occurring mainly above 900 m asl. up to altitudes exceeding 2000 m, having measured annual precipitation between 800 and 1500 mm, and an arid season of two to five months. PMID:25166320

  14. Helping enhances productivity in campo flicker (Colaptes campestris) cooperative groups.

    PubMed

    Dias, Raphael Igor; Webster, Michael S; Macedo, Regina H

    2015-06-01

    Reproductive adults in many bird species are assisted by non-breeding auxiliary helpers at the nest, yet the impact of auxiliaries on reproduction is variable and not always obvious. In this study, we tested Hamilton's rule and evaluated the effect of auxiliaries on productivity in the facultative cooperative breeder campo flicker (Colaptes campestris campestris). Campo flickers have a variable mating system, with some groups having auxiliaries and others lacking them (i.e., unassisted pairs). Most auxiliaries are closely related to the breeding pair (primary auxiliaries), but some auxiliaries (secondary auxiliaries) are unrelated females that joined established groups. We found no effect of breeder quality (body condition) or territory quality (food availability) on group productivity, but the presence of auxiliaries increased the number of fledglings produced relative to unassisted pairs. Nonetheless, the indirect benefit of helping was small and did not outweigh the costs of delayed breeding and so seemed insufficient to explain the evolution of cooperative breeding in campo flickers. We concluded that some ecological constraints must limit dispersal or independent breeding, making staying in the group a "best-of-a-bad-job" situation for auxiliaries.

  15. Sistemas Correctores de Campo Para EL Telescopio Cassegrain IAC80

    NASA Astrophysics Data System (ADS)

    Galan, M. J.; Cobos, F. J.

    1987-05-01

    El proyecto de instrumentación de mayor importancia que ha tenido el Instituto de Astrofisica de Canarias en los últimos afios ha sido el diseflo y construcción del te1escopio IAC8O. Este requería del esfuerzo con junto en mec´nica, óptica y electrónica, lo que facilitó la estructuración y el crecimiento de los respectivos grupos de trabajo, que posteriormente se integraron en departamentos En su origen (1977), el telescopio IAC80 fue concebido como un sistema clásico tipo Cassegrain, con una razón focal F/i 1.3 para el sistema Casse grain y una razón focal F/20 para el sistema Coudé. Posteriormente, aunque se mantuvo la filosofia de que el sistema básico fuera el F/11.3, se consideró conveniente el diseño de secundarios para razones focales F/16 y F/32, y se eliminó el de F/20. Sin embargo, dada la importancia relativa que un foco estrictamente fotográfico tiene en un telescopio moderno, diseñado básicamente para fotometría fotoeléctrica y con un campo util mínimamente de 40 minutos de arco, se decídió Ilevar a cabo el diseño de un secundario F/8 con un sistema corrector de campo, pero que estuviera formado únicamente por lentes con superficies esféricas para que asl su construcción fuera posible en España ó en México. La creciente utilización de detectores bidimensionales para fines de investigación astron6mica y la viabilidad de que en un futuro cercano éstos tengan un área sensible cada vez mayor, hicieron atractiva la idea de tener diseñado un sistema corrector de campo para el foco primario (F/3), con un campo útil mínimo de un grado, y también con la limitante de que sus componentes tuvieron sólamente supérficies esféricas. Ambos diseños de los sis-temas correctores de campo se llevaron a cabo, en gran medida, como parte de un proyecto de colaboración e intercambio en el área de diseño y evaluación de sistemas ópticos.

  16. Volcanism-sedimentation interaction in the Campo de Calatrava Volcanic Field (Spain): a magnetostratigraphic and geochronological study

    NASA Astrophysics Data System (ADS)

    Herrero-Hernández, Antonio; López-Moro, Francisco Javier; Gallardo-Millán, José Luis; Martín-Serrano, Ángel; Gómez-Fernández, Fernando

    2015-01-01

    This work focuses on the influence of Cenozoic volcanism of the Campo de Calatrava volcanic field on the sedimentation of two small continental basins in Spain (Argamasilla and Calzada-Moral basins). The volcanism in this area was mainly monogenetic, according to the small-volume volcanic edifices of scoria cones that were generated and the occurrence of tuff rings and maars. A sedimentological analysis of the volcaniclastic deposits led to the identification of facies close to the vents, low-density (dilute) pyroclastic surges, secondary volcanic deposits and typical maar deposits. Whole-rock K/Ar dating, together with palaeomagnetic constraints, yielded an age of 3.11-3.22 Ma for the onset of maar formation, the deposition finished in the Late Gauss-Early Matuyana. Using both techniques and previous paleontological data allowed it to be inferred that the maar formation and the re-sedimentation stage that occurred in Argamasilla and Calzada-Moral basins were roughly coeval. The occurrence of syn-eruption volcaniclastic deposits with small thicknesses that were separated by longer inter-eruption periods, where fluvial and lacustrine sedimentation was prevalent, together with the presence of small-volume volcanic edifices indicated that there were short periods of volcanic activity in this area. The volcanic activity was strongly controlled by previous basement faults that favoured magma feeding, and the faults also controlled the location of volcanoes themselves. The occurrence of the volcanoes in the continental basins led to the creation of shallow lakes that were related to the maar formation and the modification of sedimentological intra-basinal features, specifically, valley slope and sediment load.

  17. Quantitative finger dermatoglyphics in a Spanish population (Tierra de Campos).

    PubMed

    Martín, J; Portabales, D

    1986-09-01

    This study deals with the finger ridge counts and the distribution of their frequencies drawn from a Spanish sample consisting of 833 school-children (417 males and 416 females), which has been collected from the geographical area of Tierra de Campos. Paired t-test and Student-t-test were used to explore bimanual and sexual differences, respectively. The results showed: a bimanual asymmetry marked by significantly higher right hand ridge count for thumb and index pairs in both males and females, ridge counts of males are always higher than the corresponding values of females; the differences being significant excepting for right and left index and for left ring-finger. The frequency distribution of TFRC was slightly, but significantly, different from normality only in males, as Kolmogorov test showed. A great homogeneity between values for TFRC of males and females from Tierra de Campos and those of the available Spanish and Portuguese populations has been found, the values being high not only in the variation ranges of the Spanish and Portuguese populations, but also in the ranges reported for other European populations.

  18. The Campo Imperatore Near Earth Object Survey (CINEOS)

    NASA Astrophysics Data System (ADS)

    Boattini, Andrea; D'Abramo, Germano; Valsecchi, Giovanni B.; Carusi, Andrea; di Paola, Andrea; Bernardi, Fabrizio; Jedicke, Robert; Harris, Alan W.; Dotto, Elisabetta; de Luise, Fiore; Perna, Davide; Leoni, Riccardo

    2007-06-01

    The Campo Imperatore Near Earth Object Survey (CINEOS) is an Italian survey dedicated to the search and follow-up of Near Earth Objects (NEOs). It is operated with the 90 cm f/3 Schmidt telescope at the Campo Imperatore of the Rome Astronomical Observatory (INAF-OAR) as a joint project with the Istituto di Astrofisica Spaziale and Fisica Cosmica (INAF-IASF) in Rome. Since the end of 2001 CINEOS has covered about 4,250 sq. deg to 20th magnitude in the course of about 160 nights. This effort led to the discovery of 7 Near Earth Asteroids (NEAs), 1 comet (167P/CINEOS; a member of the Centaur group) and a few other unusual objects including 2004 XH50 with a unique comet-like orbit. CINEOS has also contributed almost 2,200 preliminary designations and over 30,000 detections to the Minor Planet Center. About 20% of the survey effort was carried out at low solar elongations (LSE), although no object with an orbit interior (Inner Earth Objects, IEO class) or nearly interior to the Earth (Aten class) was found. The work at LSE was, however, very important to test survey strategies implemented with larger telescopes. We also provide the results of a CINEOS simulation on a reliable NEO population model based on the results of two larger scale surveys, Spacewatch and LINEAR.

  19. 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).

  20. ``Campo del Cielo'' Meteorites: Astronomical Heritage and Cultural Colonialism

    NASA Astrophysics Data System (ADS)

    López, Alejandro Martín; Altman, Agustina

    2012-09-01

    In the province of Chaco, Argentina, there is a very unique dispersion of metallic meteorites called ``Campo del Cielo''. One of the meteoric fragments of this dispersion, the meteorite called ``El Chaco'', consisting of 37 tons, is the second heaviest in the world. These meteorites are of great importance to the worldview of the Moqoit, aboriginal people that inhabit this region. For the local Creole population the meteorites are also relevant, that's why they have being cited in numerous documents and reports since the colonial period. During the first months of 2012, two Argentine artists and the Artistic Director of the German contemporary art exhibition called dOCUMENTA (13) tried to move ``El Chaco'' meteorite to Germany in order to exhibit it as an artistic object. Due to the fact that moving the meteorite could have a negative impact according to the Moqoit cosmology and that they were not able to participate in the decision they begun a manifestation against the movement of El Chaco. The opposition made by aboriginal communities and experts in cultural astronomy was able to stop the transfer. The whole process and its impact on the local community have promoted a deep discussion about art, science and cultural colonialism. In this paper we aim to address this debate and its consequences. This will allow us to think about contemporary forms of colonialism that are hidden in many scientific and artistic projects. Furthermore, we aim to debate about the most effective ways of protecting astronomical heritage in the Third World.

  1. "Ask Argonne" - Edwin Campos, Research Meteorologist, Part 1

    ScienceCinema

    Edwin Campos

    2016-07-12

    Dr. Edwin Campos is a Research Meteorologist at Argonne National Laboratory. For the last two decades, he has studied weather, and in particular, clouds. Clouds are one of the most uncertain variables in climate predictions and are often related to transportation hazards. Clouds can also impact world-class sporting events like the Olympics. You may have questions about the role of clouds, or weather, on our daily lives. How is severe weather monitored for airports? What is the impact of clouds and wind on the generation of electricity? One of the projects Edwin is working on is short-term forecasting as it relates to solar electricity. For this, Edwin's team is partnering with industry and academia to study new ways of forecasting clouds, delivering technologies that will allow the incorporation of more solar power into the electric grid. Post a question for Edwin as a comment below, and it might get answered in the follow-up video we'll post in the next few weeks.

  2. "Ask Argonne" - Edwin Campos, Research Meteorologist, Part 1

    SciTech Connect

    Edwin Campos

    2013-05-08

    Dr. Edwin Campos is a Research Meteorologist at Argonne National Laboratory. For the last two decades, he has studied weather, and in particular, clouds. Clouds are one of the most uncertain variables in climate predictions and are often related to transportation hazards. Clouds can also impact world-class sporting events like the Olympics. You may have questions about the role of clouds, or weather, on our daily lives. How is severe weather monitored for airports? What is the impact of clouds and wind on the generation of electricity? One of the projects Edwin is working on is short-term forecasting as it relates to solar electricity. For this, Edwin's team is partnering with industry and academia to study new ways of forecasting clouds, delivering technologies that will allow the incorporation of more solar power into the electric grid. Post a question for Edwin as a comment below, and it might get answered in the follow-up video we'll post in the next few weeks.

  3. 76 FR 29261 - Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Campo Wind Energy...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-20

    ... Campo Wind Energy Project, San Diego County, CA AGENCY: Bureau of Indian Affairs, Interior. ACTION... necessary for preparing an Environmental Impact Statement (EIS) for the proposed Campo Shu'luuk Wind Project... San Diego, California. Construction of the Shu'luuk Wind Project within the Campo Reservation...

  4. Post-breakup Basin Evolution along the South-Atlantic Margins

    NASA Astrophysics Data System (ADS)

    Strozyk, Frank; Back, Stefan; Kukla, Peter

    2014-05-01

    The post-breakup tectono-stratigraphic evolution of large offshore basins along the South American and African continental margins record strongly varying post-rift sedimentary successions. The northernmost segment of the South Atlantic rift and salt basins is characterized by a pronounced asymmetry, with the Brazilian margin comprising narrower and deeper rift basins with less salt in comparison to the Congo-Gabon conjugate margin. Another important observation is that multiple phases of uplift and subsidence are recorded after the break-up of the southern South Atlantic on both sides of the Florianopolis-Walvis Ridge volcanic complex, features that are regarded as atypical when compared to published examples of other post-breakup margin successions. A regional comparison based on tectonic-stratigraphic analysis of selected seismic transects between the large basins offshore southern Brazil (Espirito Santo Basin, Campos Basin, Santos Basin, Pelotas Basin) and southwest Africa (Lower Congo Basin, Kwanza Basin, Namibe Basin, Walvis Basin) provides a comprehensive basin-to-basin documentation of the key geological parameters controlling ocean and continental margin development. This comparison includes the margin configuration, subsidence development through time, sediment influx and storage patterns, type of basin fill (e.g. salt vs. non-salt systems; carbonate-rich vs. clastics-dominated systems) and finally major tectonic and magmatic events. Data from the salt basins indicate that salt-related tectonic deformation is amongst the prime controls for the non-uniform post-rift margin development. The diversity in the stratigraphic architecture of the conjugate margins offshore southern Brazil, Namibia and Angola reflects variations in the interplay of a number of controlling factors, of which the most important are (a) the structural configuration of each margin segment at the time of break-up, (b) the post break-up subsidence history of the respective margin segment

  5. Comparative structural reconstruction of the post-breakup succession in conjugated salt and salt-free basins offshore South-America and South-Africa

    NASA Astrophysics Data System (ADS)

    Strozyk, Frank; Back, Stefan; Kukla, Peter

    2013-04-01

    This project focuses on the post-breakup tectono-stratigraphic development of large offshore basins along the South American and African continental margins that record strongly varying post-rift sedimentary successions. The northernmost segment of the South Atlantic rift and salt basins is characterized by a pronounced asymmetry, with the Brazilian margin comprising narrower and deeper rift basins with less salt in comparison to the Congo-Gabon conjugate margin. Another important observation is that multiple phases of uplift and subsidence are recorded after the break-up of the southern South Atlantic on both sides of the Florianopolis-Walvis Ridge volcanic complex, features that are regarded as atypical when compared to published examples of other post-breakup margin successions. In this study we show a regional comparison between the large basins offshore southern Brazil (Espirito Santo Basin, Campos Basin, Santos Basin, Pelotas Basin) and southwest Africa (Lower Congo Basin, Kwanza Basin, Namibe Basin, Walvis Basin, etc). A sequential reconstruction of tectonic and stratigraphic elements of representative geological transects provides a comprehensive basin-to-basin documentation of the influence of key geological parameters controlling ocean and continental margin development. These include the subsidence development through time, sediment input, flux and storage patterns, salt vs. non-salt systems, carbonate-rich vs. clastics-dominated successions and finally major tectonic and magmatic events. Data from the salt basins indicate that salt-related tectonic deformation is amongst the prime controls for the non-uniform post-rift margin development.

  6. Post-breakup Basin Evolution along the South-Atlantic Margins in Brazil and Angola/Namibia

    NASA Astrophysics Data System (ADS)

    Kukla, P. A.; Strozyk, F.; Back, S.

    2013-12-01

    The post-breakup tectono-stratigraphic evolution of large offshore basins along the South American and African continental margins record strongly varying post-rift sedimentary successions. The northernmost segment of the South Atlantic rift and salt basins is characterized by a pronounced asymmetry, with the Brazilian margin comprising narrower and deeper rift basins with less salt in comparison to the Congo-Gabon conjugate margin. Another important observation is that multiple phases of uplift and subsidence are recorded after the break-up of the southern South Atlantic on both sides of the Florianopolis-Walvis Ridge volcanic complex, features that are regarded as atypical when compared to published examples of other post-breakup margin successions. A regional comparison based on tectonic-stratigraphic analysis of selected seismic transects between the large basins offshore southern Brazil (Espirito Santo Basin, Campos Basin, Santos Basin, Pelotas Basin) and southwest Africa (Lower Congo Basin, Kwanza Basin, Namibe Basin, Walvis Basin) provides a comprehensive basin-to-basin documentation of the key geological parameters controlling ocean and continental margin development. This comparison includes the margin configuration, subsidence development through time, sediment influx and storage patterns, type of basin fill (e.g. salt vs. non-salt systems; carbonate-rich vs. clastics-dominated systems) and finally major tectonic and magmatic events. Data from the salt basins indicate that salt-related tectonic deformation is amongst the prime controls for the non-uniform post-rift margin development. The diversity in the stratigraphic architecture of the conjugate margins offshore southern Brazil, Namibia and Angola reflects variations in the interplay of a number of controlling factors, of which the most important are (a) the structural configuration of each margin segment at the time of break-up, (b) the post break-up subsidence history of the respective margin segment

  7. 76 FR 6153 - Supplemental Environmental Impact Statement for the Proposed Campo Regional Landfill Project on...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... Federal Register on November 8, 2005 (70 FR 67738-67739). The Notice of Availability of the Draft SEIS was published in the Federal Register on February 26, 2010 (75 FR 8986- 8988). Public Comment Availability... Landfill Project on the Campo Indian Reservation, San Diego County, CA AGENCY: Bureau of Indian...

  8. Ground-water in the Teresina-Campo Maior area, Piaui, Brazil

    USGS Publications Warehouse

    Rodis, Harry G.; Suszczynski, Edison F.

    1972-01-01

    The Teresina-Campo Maior area lies in a presently developing farming and grazing region near the margin of drought-prone northeast Brazil where irrigated farming offers the best potential for economic development. The area comprises 9,700 square kilometers largely of catinga-covered tabular uplands which are drained by the perennial Rio Parnatba. The climate is hot and humid most of the year but with distinct wet and dry seasons. Temperature extremes range from 20?C to 39?C and the annum rainfall averages 1,200 millimeters. The area's ground-water reservoir is contained chiefly in sandstone aquifers of six westward-dipping sedimentary rock formations, all part of the Maranhao sedimentary basin. The youngest of these formations, namely the Piaut (Pennsylvarian), Poti (Mississippian), Longa (Upper Devonian), and Cabecas (Middle Devoniar), contain the principal aquifers. Precipitation is the primary source of recharge to these aquifers and is more than sufficient to replenish current withdrawals from wells. Underlying the principal aquifers are the untapped Pimenteiras and Serra Grande Formations (both Lower Devonian) which in areas adjacent to the report area are moderately good to excellent water producers. These aquifers are recharged principally by lateral inflow from the east. Water also occurs in the alluvial deposits (Quaternary) underlying the flood plain of the Rio Parnatba but recurrent and uncontrolled flooding at present (1966) precludes their development. Of little economic importance, because they lie above the zone of saturation, are the thin erosional remnants of the Pastos Bons (Upper Triassic), Matuca, and Pedra de Fogo (both Permian) Formations. There are in the report area about 200 drilled wells most of which are pumped with power-driven engines. The wells range from 40 to 500 meters deep but most do not exceed 150 meters, and practically all are completed open hole. Yields range from 500 liters per day for 6-inch-diameter domestic wells to 240

  9. 78 FR 34373 - Campo Verde Solar, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Campo Verde Solar, LLC; Supplemental Notice That Initial Market- Based Rate...-referenced proceeding of Campo Verde Solar, LLC's application for market-based rate authority, with...

  10. 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.

  11. Vascular plant community composition from the campos rupestres of the Itacolomi State Park, Brazil

    PubMed Central

    Leyh, Werner; Miazaki, Angela S.; Meira-Neto, João A.A.

    2015-01-01

    Abstract Campos rupestres are rare and endangered ecosystems that accommodate a species-rich flora with a high degree of endemism. Here, we make available a dataset from phytosociological surveys carried out in the Itacolomi State Park, Minas Gerais, southeastern Brazil. All species in a total of 30 plots of 10 x 10 m from two study sites were sampled. Their cardinality, a combination of cover and abundance, was estimated. Altogether, we registered occurrences from 161 different taxa from 114 genera and 47 families. The families with the most species were Poaceae and Asteraceae, followed by Cyperaceae. Abiotic descriptions, including soil properties such as type, acidity, nutrient or aluminum availability, cation exchange capacity, and saturation of bases, as well as the percentage of rocky outcrops and the mean inclination for each plot, are given. This dataset provides unique insights into the campo rupestre vegetation, its specific environment and the distribution of its diversity. PMID:25829858

  12. Preliminary statistical studies concerning the Campos RJ sugar cane area, using LANDSAT imagery and aerial photographs

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Costa, S. R. X.; Paiao, L. B. F.; Mendonca, F. J.; Shimabukuro, Y. E.; Duarte, V.

    1983-01-01

    The two phase sampling technique was applied to estimate the area cultivated with sugar cane in an approximately 984 sq km pilot region of Campos. Correlation between existing aerial photography and LANDSAT data was used. The two phase sampling technique corresponded to 99.6% of the results obtained by aerial photography, taken as ground truth. This estimate has a standard deviation of 225 ha, which constitutes a coefficient of variation of 0.6%.

  13. Oil discoveries and basin resource prediction in Latin America: Past, present, and future

    SciTech Connect

    Kronman, G.E.; Aleman, A.M.; Rushworth, S.W. )

    1993-02-01

    Over 350 oil discoveries were made in Latin America during the 1980s. About 12% are estimated to contain reserves greater than 100 MMBO. Several of the larger finds (>500 MMBO), such as Cusiana (Colombia), Furrial/Musipan (Venezuela), Cano Lima (Colombia) and Marlim (Brazil) represent an important part of the giant field found worldwide since 1980. Most of the larger discoveries were made by national oil companies in Venezuela, Mexico and Brazil. Undiscovered oil resources of 40-80 BBO are estimated to remain in the highest potential Latin American basins, including those in Mexico, based on historical field size data and current geological knowledge. Over 150 BBO of produced oil and proven reserves has been found in the same group of basins. The probability of finding large undiscovered oil and gas fields (>100 MMBOE) in selected established and mature Latin American basins is high. The Campos (Brazil), Llanos (Colombia), Magadalena (Colombia), Maracaibo (Venezuela), Marahon-Oriente-Putomayo (Peru-Ecuador-Colombia), Maturin (Venezuela), Reforma-Campeche (Mexico) and Ucayali (Peru) basins have the best possibility for such accumulations. Another tier of frontier and emerging basins may also contain significant resources, but limited data makes it difficult to estimate their undiscovered resources. Some of the higher potential basins in this group include the Sierra de Chiapas (Mexico/Guatemala), Huallaga (Peru), Yucatan (Mexico), Sabinas, and Burgos (Mexico) basins.

  14. 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.

  15. Origin of cratonic basins

    SciTech Connect

    de V. Klein, G.; Hsui, A.T.

    1987-12-01

    Tectonic subsidence curves show that the Illinois, Michigan, and Williston basins formed by initial fault-controlled mechanical subsidence during rifting and by subsequent thermal subsidence. Thermal subsidence began around 525 Ma in the Illinois Basin, 520-460 Ma in the Michigan Basin, and 530-500 Ma in the Williston Basin. In the Illinois Basin, a second subsidence episode (middle Mississippian through Early Permian) was caused by flexural foreland subsidence in response to the Alleghanian-Hercynian orogeny. Past workers have suggested mantle phase changes at the base of the crust, mechanical subsidence in response to isostatically uncompensated excess mass following igneous intrusions, intrusion of mantle plumes into the crust, or regional thermal metamorphic events as causes of basin initiation. Cratonic basins of North America, Europe, Africa, and South America share common ages of formation, histories of sediment accumulation, temporal volume changes of sediment fills, and common dates of interregional unconformities. Their common date of formation suggests initiation of cratonic basins in response to breakup of a late Precambrian supercontinent. This supercontinent acted as a heat lens that caused partial melting of the lower crust and upper mantle followed by emplacement of anorogenic granites during extensional tectonics in response to supercontinent breakup. Intrusion of anorogenic granites and other partially melted intrusive rocks weakened continental lithosphere, thus providing a zone of localized regional stretching and permitting formation of cratonic basins almost simultaneously over sites of intrusion of these anorogenic granites and other partially melted intrusive rocks.

  16. Regional comparison of syn- and post-rift sequences in salt and salt-free basins offshore Brazil and Angola/Namibia, South Atlantic

    NASA Astrophysics Data System (ADS)

    Strozyk, Frank; Back, Stefan; Kukla, Peter

    2015-04-01

    The large South Atlantic basins offshore South America and Africa record a highly variable syn- to post-breakup tectono-stratigraphic development. The present-day diversity in the structural and sedimentary architecture of the conjugate margins offshore southern Brazil, Namibia and Angola reflects variations in the interplay of a number of controlling factors, of which the most important are i) the structural configuration of each margin segment at the time of break-up, ii) the post break-up geodynamic history including tectonics and magmatism, and iii) variations in the type, quantity and distribution of sediment input to the respective margin segment. Particularly the basins around the Rio Grande Rise - Walvis Ridge volcanic complex show a pronounced tectono-stratigraphic asymmetry both along the respective continental margin and across the Atlantic. Only a few attempts exist to establish a regional tectono-stratigraphic correlation framework across the South Atlantic Ocean, mainly because of the lack of data across entire margin segments and limited resolution of basin wide geophysics. Still unresolved issues particularly concern the explanation of the basin-specific geological evolution of respective margin segments along the same continental margin, as well as the correlation of conjugate basins and margin segments across the Atlantic Ocean. In our study we present interpretations and first-pass restorations of regional 2D seismic-reflectivity data from the large basins offshore Brazil (Pelotas Basin, Santos Basin, Campos Basin, Espirito Santo Basin), and offshore Namibia and Angola (Walvis Basin, Namibe Basin, Benguela Basin, Kwanza Basin), which represent four adjacent pairs of conjugate basins on both sides of the South Atlantic. Results are used to document and compare on a basin-scale the contrasting styles of rift and post-rift settings during and after the continental breakup.

  17. Origin of cratonic basins

    NASA Astrophysics Data System (ADS)

    Dev. Klein, George; Hsui, Albert T.

    1987-12-01

    Tectonic subsidence curves show that the Illinois, Michigan, and Williston basins formed by initial fault-controlled mechanical subsidence during rifting and by subsequent thermal subsidence. Thermal subsidence began around 525 Ma in the Illinois Basin, 520 460 Ma in the Michigan Basin, and 530 500 Ma in the Williston Basin. In the Illinois Basin, a second subsidence episode (middle Mississippian through Early Permian) was caused by flexural foreland subsidence in response to the Alleghanian-Hercynian orogeny. Resurgent Permian rifting in the Illinois Basin is inferred because of intrusion of well-dated Permian alnoites; such intrusive rocks are normally associated with rifting processes. The process of formation of these cratonic basins remains controversial. Past workers have suggested mantle phase changes at the base of the crust, mechanical subsidence in response to isostatically uncompensated excess mass following igneous intrusions, intrusion of mantle plumes into the crust, or regional thermal metamorphic events as causes of basin initiation. Cratonic basins of North America, Europe, Africa, and South America share common ages of formation (around 550 to 500 Ma), histories of sediment accumulation, temporal volume changes of sediment fills, and common dates of interregional unconformities. Their common date of formation suggests initiation of cratonic basins in response to breakup of a late Precambrian super-continent. This supercontinent acted as a heat lens that caused partial melting of the lower crust and upper mantle followed by emplacement of anorogenic granites during extensional tectonics in response to supercontinent breakup. Intrusion of anorogenic granites and other partially melted intrusive rocks weakened continental lithosphere, thus providing a zone of localized regional stretching and permitting formation of cratonic basins almost simultaneously over sites of intrusion of these anorogenic granites and other partially melted intrusive rocks.

  18. Intra-arc basins

    SciTech Connect

    Smith, G.A.

    1988-01-01

    Convergent-margin tectonic models feature forearc and back-arc basins and generally portray the arc itself as structurally static. However, intra-arc tectonics not only control distribution and petrology of extrusives and plutons, but also generate basins along the magmatic axis. Magma withdrawal and crustal loading by volcanic edifices contribute to subsidence, but most intra-arc basins are grabens or half-grabens indicative of extension. Grabens are isolated or continuous along long segments of the arc. Basin development may alternate with periods of arc uplife. No unique set of conditions causes intra-arc extension; numerous scenarios may initiate extension and subsidence of thermally weakened arc crust. Transtension related to oblique convergence contributed to the formation of most modern intra-arc basins. Andean basins may result from gravitational spreading of an unusually highstanding arc. Intra-arc basin sediment traps may starve arc-adjacent basins from coarse volcaniclastic detritus. Terrestrial intra-arc basins accommodate thick volcanic and volcaniclastic sediment sections, including lacustrine sequences. Marine intra-arc basins include bounding carbonate shelves, marginal and local intrabasinal submarine fans and aprons, and basin plains receiving pelagic and hemipelagic sediments. Structural patterns are appropriate for trapping hydrocarbons, source rocks are commonly present, and high heat flow favors early maturation. Reservoir quality is typically poor because of volcaniclastic diagenesis, but secondary porosity from dissolution of framework feldspars and carbonate or laumontite cements, and the known productivity of some volcanic reservoirs, suggest the potential for hydrocarbon accumulations. Geothermal resources and modest coal potential have also been recognized.

  19. Evaluation of genotoxicity and cytotoxicity of water samples from the Sinos River Basin, southern Brazil.

    PubMed

    Bianchi, E; Goldoni, A; Trintinaglia, L; Lessing, G; Silva, C E M; Nascimento, C A; Ziulkoski, A L; Spilki, F R; Silva, L B

    2015-05-01

    Some water bodies in the Sinos River Basin (SRB) have been suffering the effects of pollution by residential, industrial and agroindustrial wastewater. The presence of cytotoxic and genotoxic compounds could compromise the water quality and the balance of these ecosystems. In this context, the research aimed to evaluate the genotoxicity and cytotoxicity of the water at four sites along the SRB (in the cities of Santo Antônio da Patrulha, Parobé, Campo Bom and Esteio), using bioassays in fish and cell culture. Samples of surface water were collected and evaluated in vitro using the Astyanax jacuhiensis fish species (micronucleus test and comet assay) and the Vero lineage of cells (comet assay and cytotoxicity tests, neutral red - NR and tetrazolium MTT). The micronucleus test in fish showed no significant differences between the sampling sites, and neither did the comet assay and the MTT and NR tests in Vero cells. The comet assay showed an increase in genetic damage in the fish exposed to water samples collected in the middle and lower sections of the basin (Parobé, Campo Bom and Esteio) when compared to the upper section of the basin (Santo Antônio da Patrulha). The results indicate contamination by genotoxic substances starting in the middle section of the SRB.

  20. Evaluation of genotoxicity and cytotoxicity of water samples from the Sinos River Basin, southern Brazil.

    PubMed

    Bianchi, E; Goldoni, A; Trintinaglia, L; Lessing, G; Silva, C E M; Nascimento, C A; Ziulkoski, A L; Spilki, F R; Silva, L B

    2015-05-01

    Some water bodies in the Sinos River Basin (SRB) have been suffering the effects of pollution by residential, industrial and agroindustrial wastewater. The presence of cytotoxic and genotoxic compounds could compromise the water quality and the balance of these ecosystems. In this context, the research aimed to evaluate the genotoxicity and cytotoxicity of the water at four sites along the SRB (in the cities of Santo Antônio da Patrulha, Parobé, Campo Bom and Esteio), using bioassays in fish and cell culture. Samples of surface water were collected and evaluated in vitro using the Astyanax jacuhiensis fish species (micronucleus test and comet assay) and the Vero lineage of cells (comet assay and cytotoxicity tests, neutral red - NR and tetrazolium MTT). The micronucleus test in fish showed no significant differences between the sampling sites, and neither did the comet assay and the MTT and NR tests in Vero cells. The comet assay showed an increase in genetic damage in the fish exposed to water samples collected in the middle and lower sections of the basin (Parobé, Campo Bom and Esteio) when compared to the upper section of the basin (Santo Antônio da Patrulha). The results indicate contamination by genotoxic substances starting in the middle section of the SRB. PMID:26270216

  1. Reserves in western basins

    SciTech Connect

    Caldwell, R.H.; Cotton, B.W.

    1995-04-01

    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  2. River basin administration

    NASA Astrophysics Data System (ADS)

    Management of international rivers and their basins is the focus of the Centre for Comparative Studies on (International) River Basin Administration, recently established at Delft University of Technology in the Netherlands. Water pollution, sludge, and conflicting interests in the use of water in upstream and downstream parts of a river basin will be addressed by studying groundwater and consumption of water in the whole catchment area of a river.Important aspects of river management are administrative and policy aspects. The Centre will focus on policy, law, planning, and organization, including transboundary cooperation, posing standards, integrated environmental planning on regional scale and environmental impact assessments.

  3. Tertiary Basins of Spain

    NASA Astrophysics Data System (ADS)

    Friend, Peter F.; Dabrio, Cristino J.

    1996-01-01

    During the Tertiary, Spain suffered compressional collision between France and Africa, and its Atlantic and Mediterranean coasts have been further modified by extensional rifting. Because it includes sectors of two separate foreland basins, and an intervening craton with basins that have been influenced by extensional and strikeSHslip deformation, Spain provides excellent material for the development and testing of theories on the study of sedimentary basin formation and filling. This book is one of the few studies available in English of the important Tertiary geology of Spain.

  4. Testing arbitrary classes of light in a physiognomically heterogeneous area of "campo rupestre" vegetation.

    PubMed

    Moreira, Ana S F P; Borba, Eduardo L; Lemos-Filho, José P

    2013-01-01

    The Brazilian "campo rupestre" vegetation shows high light heterogeneity, characteristic which is often disregarded in ecophysiological studies due the difficult of obtaining accurate measurements in a complex environment. The aim of the present study it was to describe how much heterogeneous is the light distribution in this environment, as well as tried to define classes in relation to the photosynthetically active radiation (PAR) for 30 rupicolous individuals of Bulbophyllum involutum. The individuals were marked and previously classified in light classes visually predetermined ("full sun", "partially shaded" and "shaded"). Once defined these classes, principal component analysis, cluster and dispersal analyses using direct and indirect PAR measures were performed to characterize the environment as well as to validate the inclusion of the individuals in each class. The use of multivariate analysis increased the accuracy of predetermined classes of light, and some individuals from "shaded" and "partially shaded" classes needed to be regrouped. After individuals' reclassification, amplitude of PAR variance was reduced in each class, enhancing homogeneity. Ours results show the possibility to evaluate light environment conditions more precisely in "campo rupestre" vegetation using multivariate analysis, allowing the increase in accuracy of this parameter for ecophysiological researches.

  5. K Basin Hazard Analysis

    SciTech Connect

    PECH, S.H.

    2000-08-23

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  6. K Basins Hazard Analysis

    SciTech Connect

    WEBB, R.H.

    1999-12-29

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Safety Analysis Report (HNF-SD-WM-SAR-062, Rev.4). This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  7. The aquatic and semiaquatic biota in Miocene amber from the Campo LA Granja mine (Chiapas, Mexico): Paleoenvironmental implications

    NASA Astrophysics Data System (ADS)

    Serrano-Sánchez, María de Lourdes; Hegna, Thomas A.; Schaaf, Peter; Pérez, Liseth; Centeno-García, Elena; Vega, Francisco J.

    2015-10-01

    Amber from the Campo La Granja mine in Chiapas, Mexico, is distinct from other sources of amber in Chiapas. Campo La Granja amber has distinct layers created by successive flows of resin with thin layers of sand on most surfaces. Aquatic and semi-aquatic arthropods are commonly found. Together these pieces of evidence suggest an estuarine environment similar to modern mangrove communities. The aquatic crustaceans are the most intriguing aspect of the biota. A large number of ostracods have been found in the amber-many with their carapaces open, suggesting that they were alive and submerged in water at the time of entombment. The only known examples of brachyuran crabs preserved in amber are found in the Campo La Granja amber. Amphipods, copepods, isopods, and tanaids are also members of the crustacean fauna preserved in amber.

  8. The Permian post-orogenic collapse in the Alps: insights from the Campo unit (Austroalpine nappes, N-Italy, SE-Switzerland)

    NASA Astrophysics Data System (ADS)

    Petri, Benoît; Mohn, Geoffroy; Štípská, Pavla; Manatschal, Gianreto; Schulmann, Karel

    2014-05-01

    The final stage of the Variscan orogeny (310-270 Ma) is characterized by an intense tectonic, magmatic and metamorphic event. During the Permian, acid and mafic intrusions were emplaced at all crustal levels and are associated to high-temperature contact metamorphism. While most of the studies focus either on the formation of Permian basins or on the lower crustal magmatic and metamorphic evolution, the characterization of the middle crust is lacking. Therefore, this study aims to unravel the processes active at mid-crustal levels during the Permian. We investigate the contact aureole of the Sondalo gabbro emplaced in a mid-crustal position during the Permian, exposed in the Austroalpine Campo unit (N-Italy). This work is based on a multidisciplinary approach linking structural geology, metamorphic petrology and geochronology. The country rock of the gabbroic intrusion is composed of Grt-St micaschists and paragneisses indicating a prograde path in the amphibolite facies associated with the formation of a N-W steeply dipping S2 foliation. This foliation is pervasively reworked by a N-E trending sub-vertical S3 fabric made of Ms-Bt metasediments. This S3 fabric is also found in metapelitic septa in the core of the mafic intrusion, whereas in the narrow contact aureole a moderately dipping S4 fabric roughly parallel to the margins of the pluton is developed. From host-rock to the center of the intrusion, the metapelites show destabilization of muscovite, appearance of sillimanite, spinel, cordierite, crystallization of a large amount of garnet and finally disappearance of biotite and potassic feldspar. As a consequence, the kinzigitic restites of the contact aureole are replaced by Grt-Sil-Crd-Spl granulites in an intra-plutonic position. Qualitative P-T estimates indicate a barrovian prograde path during D2, similar to P-T evolutions found in other Austroalpine units (e.g. Ulten zone). Thermodynamic modelling of the high-grade granulites due to the thermal effect of

  9. Radiogenic Xenon-129 in Silicate Inclusions in the Campo Del Cielo Iron Meteorite

    NASA Technical Reports Server (NTRS)

    Meshik, A.; Kurat, G.; Pravdivtseva, O.; Hohenberg, C. M.

    2004-01-01

    Iron meteorites present a challenge for the I-Xe dating technique because it is usually the inclusions, not metal, that contain radiogenic xenon and iodine. Silicate inclusions are frequent in only types IAB and IIE, and earlier studies of irons have demonstrated that I-Xe system can survive intact in these inclusions preserving valuable age information. Our previous studies of the I-Xe record in pyroxene grains from Toluca iron suggested an intriguing relationship between apparent I-Xe ages and (Mg+Fe)/Fe ratios. The I-Xe system in K-feldspar inclusions from Colomera (IIE) had the fingerprint of slow cooling, with an indicated cooling rate of 2-4 C/Ma. Here we present studies of the iodine-xenon system in a silicate-graphite-metal (SiGrMet) inclusion of the IA Campo del Cielo iron meteorite from the collection of the Museum of Natural History in Vienna.

  10. Nam Con Son Basin

    SciTech Connect

    Tin, N.T.; Ty, N.D.; Hung, L.T.

    1994-07-01

    The Nam Con Son basin is the largest oil and gas bearing basin in Vietnam, and has a number of producing fields. The history of studies in the basin can be divided into four periods: Pre-1975, 1976-1980, 1981-1989, and 1990-present. A number of oil companies have carried out geological and geophysical studies and conducted drilling activities in the basin. These include ONGC, Enterprise Oil, BP, Shell, Petro-Canada, IPL, Lasmo, etc. Pre-Tertiary formations comprise quartz diorites, granodiorites, and metamorphic rocks of Mesozoic age. Cenozoic rocks include those of the Cau Formation (Oligocene and older), Dua Formation (lower Miocene), Thong-Mang Cau Formation (middle Miocene), Nam Con Son Formation (upper Miocene) and Bien Dong Formation (Pliocene-Quaternary). The basement is composed of pre-Cenozoic formations. Three fault systems are evident in the basin: north-south fault system, northeast-southwest fault system, and east-west fault system. Four tectonic zones can also be distinguished: western differentiated zone, northern differentiated zone, Dua-Natuna high zone, and eastern trough zone.

  11. River basin management

    SciTech Connect

    Newsome, D.H.; Edwards, A.M.C.

    1984-01-01

    The quality of water is of paramount importance in the management of water resources - including marine waters. A quantitative knowledge of water quality and the factors governing it is required to formulate and implement strategies requiring an inter-disciplinary approach. The overall purpose of this conference was to bring together the latest work on water quality aspects of river basin management. These proceedings are structured on the basis of five themes: problems in international river basins; the contribution of river systems to estuarial and marine pollution; the setting of standards; monitoring; and practical water quality management including use of mathematical models. They are followed by papers from the workshop on advances in the application of mathematical modelling to water quality management, which represent some of the current thinking on the problems and concepts of river basin management.

  12. Delaware River Basin

    USGS Publications Warehouse

    Fischer, Jeffrey M.

    1999-01-01

    Assessing the quality of water in every location of the Nation would not be practical. Therefore, NAWQA investigations are conducted within 59 selected areas called study units (fig. 1). These study units encompass important river and aquifer systems in the United States and represent the diverse geographic, waterresource, land-use, and water-use characteristics of the Nation. The Delaware River Basin is one of 15 study units in which work began in 1996. Water-quality sampling in the study unit will begin in 1999. This fact sheet provides a brief overview of the NAWQA program, describes the Delaware River Basin study unit, identifies the major water-quality issues in the basin, and documents the plan of study that will be followed during the study-unit investigation.

  13. Monitoring of perfluoroalkyl substances in the Ebro and Guadalquivir River basins (Spain)

    NASA Astrophysics Data System (ADS)

    Lorenzo, Maria; Campo, Julian; Andreu, Vicente; Pico, Yolanda; Farre, Marinella; Barcelo, Damia

    2015-04-01

    Relevant concentrations of a broad range of pollutants have been found in Spanish Mediterranean River basins, as consequence of anthropogenic pressures and overexploitation (Campo et al., 2014). In this study, the occurrence and sources of 21 perfluoroalkyl substances (PFASs) were determined in water and sediment of the Ebro and Guadalquivir River basins (Spain). PFASs are persistent, bio-accumulative and toxic, which make them a hazard to human health and wildlife. The Ebro and Guadalquivir Rivers are the two most important rivers of Spain. They are representative examples of Mediterranean rivers heavily managed, and previous researches have reported their high pesticide contamination (Masiá et al., 2013). Analytes were extracted by solid phase extraction (SPE) and determined by liquid chromatography coupled to tandem mass spectrometry (LC/MS-MS). In water samples, from 21 analytes screened, 11 were found in Ebro samples and 9 in Guadalquivir ones. In both basins, the most frequents were PFBA, PFPeA, PFHxS and PFOS. Maximum concentration was detected for PFBA, with 251.3 ng L-1 in Ebro and 742.9 ng L-1 in Guadalquivir. Regarding the sediment samples, 8 PFASs were detected in those coming from Ebro basin and 9 in those from Guadalquivir. The PFASs most frequently detected were PFBA, PFPeA, PFOS and PFBS. Maximum concentration in Ebro samples was detected for PFOA, with 32.4 ng g-1 dw, and in Guadalquivir samples for PFBA with 63.8 ng g-1 dw. Ubiquity of these compounds in the environment was proved with high PFAS concentration values detected in upper parts of the rivers. Results confirm that most of the PFASs are only partially eliminated during the secondary treatment suggesting that they can be a focal point of contamination to the rivers where they can bio-accumulate and produce adverse effects on wildlife and humans. Acknowledgment The Spanish Ministry of Economy and Competitiveness has supported this work through the projects SCARCE-CSD2009-00065, CGL2011

  14. Geology, exploration status of Uruguay's sedimentary basins

    SciTech Connect

    Goso, C.; Santa Ana, H. de )

    1994-02-07

    This article attempts to present the geological characteristics and tectonic and sedimentary evolution of Uruguayan basins and the extent to which they have been explored. Uruguay is on the Atlantic coast of South America. The country covers about 318,000 sq km, including offshore and onshore territories corresponding to more than 65% of the various sedimentary basins. Four basins underlie the country: the Norte basin, the Santa Lucia basin, the offshore Punta del Este basin, and the offshore-onshore Pelotas-Merin basin. The Norte basin is a Paleozoic basin while the others are Mesozoic basins. Each basin has been explored to a different extent, as this paper explains.

  15. Trinity river basin, Texas

    USGS Publications Warehouse

    Ulery, Randy L.; Van Metre, Peter C.; Crossfield, Allison S.

    1993-01-01

    In 1991 the Trinity River Basin National Water-Quality Assessment (NAWQA) will include assessments of surface-water and ground-water quality. Initial efforts have focused on identifying water-quality issues in the basin and on the environmental factors underlying those issues. Physical characteristics described include climate, geology, soils, vegetation, physiography, and hydrology. Cultural characteristics discussed include population distribution, land use and land cover, agricultural practices, water use, an reservoir operations. Major water-quality categories are identified and some of the implications of the environmental factors for water quality are presented.

  16. Taunton River basin

    USGS Publications Warehouse

    Williams, John R.; Willey, Richard E.

    1970-01-01

    This report presents in tabular form selected records of wells, test wells, and borings collected during a study of the basin from 1966 to 1968 in cooperation with the Massachusetts Water Resources Commission, and during earlier studies. This report is released in order to make available to the public and to local, state, and federal agencies basic ground-water information that may aid in planning water-resources development. Basic records contained in this report will complement an interpretative report on the Taunton River basin to be released at a later date.

  17. Las fulguraciones como manifestación de reconexión en el campo magnético solar

    NASA Astrophysics Data System (ADS)

    Bagalá, L. G.; Mandrini, M. C.; Rovira, M. G.; Démoulin, P.

    Las fulguraciones solares son fenómenos transitorios de liberación de energía que se desarrollan en las estructuras magnéticas de las regiones activas del Sol. Las fulguraciones pueden llegar a liberar hasta 1032 erg en 100 seg. en todo el rango electromagnético, y acelerar partículas. En este trabajo mostramos que la ubicación de los abrillantamientos en Hα de diversas fulguraciones está relacionado con las propiedades de las conexiones de las líneas del campo magnético de la región, como se espera por las teorías de reconexión en 3D recientemente desarrolladas (Démoulin et al, 1996a). El campo magnético coronal se extrapola del campo fotosférico observado suponiendo una configuración libre de fuerzas lineal. Por medio de un algoritmo se determinan las regiones donde existe un cambio drástico en la conectividad de las líneas de campo (límites ``cuasi-discontinuos'', o cuasi-separatrices CS). Las CS son bandas abiertas que identifican zonas donde el campo magnético se reconectará con más probabilidad y, siempre que las mismas sean lo suficientemente finas, se producirá allíla liberación de energía proveniente del campo magnético. Hemos encontrado que en todas las regiones fulgurantes estudiadas (Démoulin et al, 1996b) existen CS en los mismos lugares donde se observaron los abrillantamientos en Hα. Allídonde coinciden los abrillantamientos con las CS, éstas tienen un espesor menor que 1 Mm. Las líneas de campo coronales extrapoladas de nuestro modelo tienen sus orígenes fotosféricos a ambos lados de las CS, como se espera dados los recientes estudios de reconexión magnética en 3D. Estos resultados ponen a prueba los modelos presentes sobre fulguraciones solares.

  18. Techniques of remote sensing applied to the environmental analysis of part of an aquifer located in the São José dos Campos Region sp, Brazil.

    PubMed

    Bressan, Mariana Affonseca; Dos Anjos, Célio Eustáquio

    2003-05-01

    The anthropogenic activity on the surface can modify and introduce new mechanisms of recharging the groundwater system, modifying the tax, the frequency and the quality of recharge of underground waters. The understanding of these mechanisms and the correct evaluation of such modifications are fundamental in determining the vulnerability of groundwater contamination. The groundwater flow of the South Paraíba Compartment, in the region of São José dos Campos, São Paulo, is directly related to structural features of the Taubaté Basin and, therefore, the analysis of its behaviour enhances the understanding of tectonic structure. The methodology adopted for this work consists in pre-processing and processing of the satellite images, visual interpretation of HSI products, field work and data integration. The derivation of the main structural features was based on visual analysis of the texture elements of drainage, and the relief in sedimentary and crystalline rocks. Statistical analysis of the feature densities and the metric-geometric relations between the analysed elements have been conducted. The crystalline rocks, on which the sediments were laying, conditions and controls the structural arrangement of sedimentary formations. The formation of the South Paraíba Grabén is associated with Cenozoic distensive movement which reactivated old features of crust weakness and generated previous cycles with normal characteristics. The environmental analysis is based on the integration of the existing methodology to characterise vulnerability of an universal pollutant and density fracture zone. The digital integration was processed using GIS (Geographic Information System) to delineate five defined vulnerability classes. The hydrogeological settings were analysed in each thematic map and, using fuzzy logic, an index for each different vulnerability class was compiled. Evidence maps could be combined in a series of steps using map algebra.

  19. 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

  20. 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.

  1. Natural frequency of regular basins

    NASA Astrophysics Data System (ADS)

    Tjandra, Sugih S.; Pudjaprasetya, S. R.

    2014-03-01

    Similar to the vibration of a guitar string or an elastic membrane, water waves in an enclosed basin undergo standing oscillatory waves, also known as seiches. The resonant (eigen) periods of seiches are determined by water depth and geometry of the basin. For regular basins, explicit formulas are available. Resonance occurs when the dominant frequency of external force matches the eigen frequency of the basin. In this paper, we implement the conservative finite volume scheme to 2D shallow water equation to simulate resonance in closed basins. Further, we would like to use this scheme and utilizing energy spectra of the recorded signal to extract resonant periods of arbitrary basins. But here we first test the procedure for getting resonant periods of a square closed basin. The numerical resonant periods that we obtain are comparable with those from analytical formulas.

  2. 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.

  3. Pollination of Cambessedesia wurdackii in Brazilian campo rupestre vegetation, with special reference to crepuscular bees.

    PubMed

    Franco, Emanuella Lopes; Gimenes, Miriam

    2011-01-01

    Cambessedesia wurdackii Martins (Myrtales: Melastomataceae) is presumably endemic to the Chapada Diamantina, Bahia State, Brazil. A majority of the species of this family are pollinated by diurnal bees that buzz the floral anthers to collect pollen. The present work examined the interactions between C. wurdackii and visiting bees, focusing on temporal, morphological, and behavioral features, especially in regards to the crepuscular bees Megalopta sodalis (Vachal) (Hymenoptera: Halictidae) and Ptiloglossa off. dubia Moure (Hymenoptera: Colletidae). The study was undertaken in an area of campo rupestre montane savanna vegetation located in the Chapada Diamantina Mountains of Bahia State, Brazil, between August/2007 and July/2008. Flowering in C. wurdackii occurred from April through July, with a peak in May. A total of 592 visits by diurnal and crepuscular bees to the flowers of C. wurdackii were recorded, with a majority of the visits made by M. sodalis and P. dubia (92%) near sunrise and sunset. The anthers of C. wurdackii are arranged in two tiers, which favors cross pollination. The morphological, temporal and behavioral characteristics of M. sodalis and P. dubia indicated that they were potential pollinators of C. wurdackii, in spite of the fact that the colorful and showy flowers of this species are more typical of a diurnal melittophilous pollination syndrome. PMID:22208813

  4. Variation of surface ozone in Campo Grande, Brazil: meteorological effect analysis and prediction.

    PubMed

    Pires, J C M; Souza, A; Pavão, H G; Martins, F G

    2014-09-01

    The effect of meteorological variables on surface ozone (O3) concentrations was analysed based on temporal variation of linear correlation and artificial neural network (ANN) models defined by genetic algorithms (GAs). ANN models were also used to predict the daily average concentration of this air pollutant in Campo Grande, Brazil. Three methodologies were applied using GAs, two of them considering threshold models. In these models, the variables selected to define different regimes were daily average O3 concentration, relative humidity and solar radiation. The threshold model that considers two O3 regimes was the one that correctly describes the effect of important meteorological variables in O3 behaviour, presenting also a good predictive performance. Solar radiation, relative humidity and rainfall were considered significant for both O3 regimes; however, wind speed (dispersion effect) was only significant for high concentrations. According to this model, high O3 concentrations corresponded to high solar radiation, low relative humidity and wind speed. This model showed to be a powerful tool to interpret the O3 behaviour, being useful to define policy strategies for human health protection regarding air pollution. PMID:24854500

  5. Canada Basin revealed

    USGS Publications Warehouse

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Chian, D; Lebedeva-Ivanova, Nina; Jackson, Ruth

    2012-01-01

    More than 15,000 line-km of new regional seismic reflection and refraction data in the western Arctic Ocean provide insights into the tectonic and sedimentologic history of Canada Basin, permitting development of new geologic understanding in one of Earth's last frontiers. These new data support a rotational opening model for southern Canada Basin. There is a central basement ridge possibly representing an extinct spreading center with oceanic crustal velocities and blocky basement morphology characteristic of spreading centre crust surrounding this ridge. Basement elevation is lower in the south, mostly due to sediment loading subsidence. The sedimentary succession is thickest in the southern Beaufort Sea region, reaching more than 15 km, and generally thins to the north and west. In the north, grabens and half-grabens are indicative of extension. Alpha-Mendeleev Ridge is a large igneous province in northern Amerasia Basin, presumably emplaced synchronously with basin formation. It overprints most of northern Canada Basin structure. The seafloor and sedimentary succession of Canada Basin is remarkably flat-lying in its central region, with little bathymetric change over most of its extent. Reflections that correlate over 100s of kms comprise most of the succession and on-lap bathymetric and basement highs. They are interpreted as representing deposits from unconfined turbidity current flows. Sediment distribution patterns reflect changing source directions during the basin’s history. Initially, probably late Cretaceous to Paleocene synrift sediments sourced from the Alaska and Mackenzie-Beaufort margins. This unit shows a progressive series of onlap unconformities with a younging trend towards Alpha and Northwind ridges, likely a response to contemporaneous subsidence. Sediment source direction appeared to shift to the Canadian Arctic Archipelago margin for the Eocene and Oligocene, likely due to uplift of Arctic islands during the Eurekan Orogeny. The final

  6. Albuquerque Basin seismic network

    USGS Publications Warehouse

    Jaksha, Lawrence H.; Locke, Jerry; Thompson, J.B.; Garcia, Alvin

    1977-01-01

    The U.S. Geological Survey has recently completed the installation of a seismic network around the Albuquerque Basin in New Mexico. The network consists of two seismometer arrays, a thirteen-station array monitoring an area of approximately 28,000 km 2 and an eight-element array monitoring the area immediately adjacent to the Albuquerque Seismological Laboratory. This report describes the instrumentation deployed in the network.

  7. Petroleum basin studies

    SciTech Connect

    Shannon, P.M. ); Naylor, D. )

    1989-01-01

    This book reviews the tectonic setting, basin development and history of exploration of a number of selected petroleum provinces located in a variety of settings in the Middle East, North Sea, Nigeria, the Rocky Mountains, Gabon and China. This book illustrates how ideas and models developed in one area may be applied to other regions. Regional reviews and the reassessment of petroleum provinces are presented.

  8. Dimension of fractal basin boundaries

    SciTech Connect

    Park, B.S.

    1988-01-01

    In many dynamical systems, multiple attractors coexist for certain parameter ranges. The set of initial conditions that asymptotically approach each attractor is its basin of attraction. These basins can be intertwined on arbitrary small scales. Basin boundary can be either smooth or fractal. Dynamical systems that have fractal basin boundary show final state sensitivity of the initial conditions. A measure of this sensitivity (uncertainty exponent {alpha}) is related to the dimension of the basin boundary d = D - {alpha}, where D is the dimension of the phase space and d is the dimension of the basin boundary. At metamorphosis values of the parameter, there might happen a conversion from smooth to fractal basin boundary (smooth-fractal metamorphosis) or a conversion from fractal to another fractal basin boundary characteristically different from the previous fractal one (fractal-fractal metamorphosis). The dimension changes continuously with the parameter except at the metamorphosis values where the dimension of the basin boundary jumps discontinuously. We chose the Henon map and the forced damped pendulum to investigate this. Scaling of the basin volumes near the metamorphosis values of the parameter is also being studied for the Henon map. Observations are explained analytically by using low dimensional model map.

  9. Great Basin Paleontological Bibliography

    USGS Publications Warehouse

    Blodgett, Robert B.; Zhang, Ning; Hofstra, Albert H.; Morrow, Jared R.

    2007-01-01

    Introduction This work was conceived as a derivative product for 'The Metallogeny of the Great Basin' project of the Mineral Resources Program of the U.S. Geological Survey. In the course of preparing a fossil database for the Great Basin that could be accessed from the Internet, it was determined that a comprehensive paleontological bibliography must first be compiled, something that had not previously been done. This bibliography includes published papers and abstracts as well as unpublished theses and dissertations on fossils and stratigraphy in Nevada and adjoining portions of California and Utah. This bibliography is broken into first-order headings by geologic age, secondary headings by taxonomic group, followed by ancillary topics of interest to both paleontologists and stratigraphers; paleoecology, stratigraphy, sedimentary petrology, paleogeography, tectonics, and petroleum potential. References were derived from usage of Georef, consultation with numerous paleontologists and geologists working in the Great Basin, and literature currently on hand with the authors. As this is a Web-accessible bibliography, we hope to periodically update it with new citations or older references that we have missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the readers think should be added. As a final note, we gratefully acknowledge the helpful reviews provided by A. Elizabeth J. Crafford (Anchorage, Alaska) and William R. Page (USGS, Denver, Colorado).

  10. Advanced Chemistry Basins Model

    SciTech Connect

    William Goddard; Mario Blanco; Lawrence Cathles; Paul Manhardt; Peter Meulbroek; Yongchun Tang

    2002-11-10

    The DOE-funded Advanced Chemistry Basin model project is intended to develop a public domain, user-friendly basin modeling software under PC or low end workstation environment that predicts hydrocarbon generation, expulsion, migration and chemistry. The main features of the software are that it will: (1) afford users the most flexible way to choose or enter kinetic parameters for different maturity indicators; (2) afford users the most flexible way to choose or enter compositional kinetic parameters to predict hydrocarbon composition (e.g., gas/oil ratio (GOR), wax content, API gravity, etc.) at different kerogen maturities; (3) calculate the chemistry, fluxes and physical properties of all hydrocarbon phases (gas, liquid and solid) along the primary and secondary migration pathways of the basin and predict the location and intensity of phase fractionation, mixing, gas washing, etc.; and (4) predict the location and intensity of de-asphaltene processes. The project has be operative for 36 months, and is on schedule for a successful completion at the end of FY 2003.

  11. Summary of water resources for the Campo, Cuyapaipe, La Posta, and Manzanita Indian Reservations and vicinity, San Diego County, California

    USGS Publications Warehouse

    Moyle, W.R.; Downing, D.J.

    1978-01-01

    Since 1945, precipitation and runoff in California on the Campo, Cuyapaipe, La Posta, and Manzanita Indian Reservations and surrounding areas generally have been below normal, and ground-water levels are declining. Most of the water is of excellent quality. The analysis of water from one well on the Campo Reservation indicates a concentration of nitrate that exceeds the recommended limit established in 1972 by the U.S. Environmental Protection Agency. Most wells and springs in the study area yield water for domestic purposes. The yields range from less than 1 gallon per minute to 210 gallons per minute. Most of the water is produced from shallow aluvial-filled channels or from consolidated rocks that are deeply weathered locally or highly fractured. The well data show that insufficient water is available on the four reservations for large-scale irrigation. (Woodard-USGS)

  12. 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.

  13. Relación entre la orientación de Nebulosas Planetarias y el campo magnético galáctico

    NASA Astrophysics Data System (ADS)

    Weidmann, W.; Díaz, R. J.; Carranza, G.

    Un estudio detallado de las orientaciones diferenciales de nebulosas planetarias en todo el cielo sugiere fuertemente una relación con la dirección de los campos magnéticos de origen galáctico, determinados en la polarización de estrellas de campo. Esto da consistencia a la hipótesis de que la orientación de las nebulosas planetarias ovaladas es inducida, al menos parcialmente, por el campo magnético general de la Vía Láctea.

  14. A geometria do campo magnético na região da nuvem Lupus 1

    NASA Astrophysics Data System (ADS)

    Alves, F. P.; Franco, G. A. P.

    2003-08-01

    Apresentaremos os resultados de uma investigação polarimétrica na região de formação estelar junto à nuvem escura Lupus 1. Esse estudo baseia-se em polarimétria CCD obtida na banda R, e cobre Lupus 1, bem como a área vizinha a essa nuvem contendo a cavidade em 100 mm IRAS. Os dados observacionais foram coletados com o telescópio IAG de 60 cm do Observatório do Pico dos Dias (LNA/MCT - Brasópolis - MG). Nossa primeira análise mostra que uma variação da orientação do campo magnético através da região pode produzir padrões complexos de polarização cuja geometria do campo não pode ser facilmente determinada. Os padrões de polarização são inconsistentes com um campo magnético estritamente uniforme e unidimensional em larga escala. Comparação com a emissão em 100 mm mostra que localmente os vetores de polarização exibem um forte alinhamento com a orientação dos padrões observados em infravermelho.

  15. Estudio de la envoltura fría en presencia de un campo magnético en estrellas tempranas

    NASA Astrophysics Data System (ADS)

    Montero, M. F.; Platzeck, A. M.

    En el estudio de la distribución espacial de la densidad en torno a estrellas tempranas, al menos en dos coordenadas, se consideran en general ``escenarios" cualitativos. Existen sólo dos modelos calculados a partir de la ecuación de conservación de momento: el de Poeckert y Marlborough (Astroph. Journal 220, 940, 1978) y el de Ringuelet e Iglesias (Astroph. Journal 369, 463, 1991). El primero es isotermo considerando campo gravitatorio y fuerza centrífuga. El segundo, resuelve un caso no isotermo en equilibrio hidrostático teniendo en cuenta los campos gravitatorios, de radiación y magnético. En esta comunicación presentamos el análisis, que se deriva de los resultados de Ringuelet e Iglesias para el caso hidrostático, de la estructura de líneas de campo magnético. A continuación estudiamos la forma en que se modifica la distribución espacial de la densidad en la envoltura fría, cuando se tiene en cuenta el movimiento del plasma.

  16. Upwelling processes along a western boundary current in the Abrolhos-Campos region of Brazil

    NASA Astrophysics Data System (ADS)

    Aguiar, A. L.; Cirano, M.; Pereira, J.; Marta-Almeida, M.

    2014-08-01

    Upwelling events observed from the years 2003 to 2011 were analyzed. Our focus was on the Abrolhos-Campos region (ACR, 15°S-23°S), which is located along the Brazilian Margin and influenced by a western boundary current, the Brazil Current (BC). Satellite sea surface temperature, National Centers for Environmental Prediction (NCEP) and Global Forecast System (GFS) wind data were used to complement the results of a high-resolution regional oceanic model to investigate the occurrence of and the mechanisms responsible for intense upwelling events in this region. These events were more frequent from 20°S to 23°S. Over 90% of the identified upwelling events were influenced by favorable wind stress. Surface Ekman transport was found to be more important for the region from Prado (17°S) to Marataízes (21°S), whereas upward Ekman pumping played a more important role from 22°S to 23°S. Current-driven upwelling processes associated with the location of the BC as well as its velocity and meso-scale activity were also analyzed. The results showed that these mechanisms are highly influenced by the local topography. Topographic effects exerted via the acceleration of the BC are more obvious in the southern ACR, while in the Prado region, BC cyclonic meanders tend to be more relevant. Moreover, eddy-driven upwelling increases in the southward direction after the passage of the Vitória-Trindade Ridge (20°S), an important submarine chain, which acts to constrain and modulate the southward flow of the BC.

  17. Geohistorical analysis of Paradox Basin

    SciTech Connect

    Lemke, L.D.

    1985-05-01

    The Paradox basin is an elongate sedimentary basin, asymmetric in profile, extending across common corners of Utah, Colorado, Arizona, and New Mexico. Subsidence of the basin began in Desmoinesian time and was coincident with the development of the ancestral Rocky Mountains. The Uncompahgre uplift formed the northeast boundary of the basin during Pennsylvanian and Permian times. Formation thickness and lithologies were obtained from lithologic and radioactivity logs from various parts of the basin. The stratigraphic column at each well, restored through the Upper Cretaceous, was back-stripped and decompacted to reconstruct its depositional history. Decompacted geohistory diagrams and residual (tectonic) subsidence curves were then generated for each well. The Mobil 1 McCormick well, drilled in 1977, penetrates Pennsylvanian strata beneath reverse-faulted granitic basement; this indicates that the basin was flexed down in response to pennsylvanian and Permian thrust faulting along the flank of the Uncompahgre uplift. However, close correspondence of the residual subsidence curves to theoretical thermal subsidence curves indicates that the basin formed by crustal extension. Consequently, development of the basin may have involved crustal stretching (transtensional.) beneath the basin floor, followed by thrusting (transpressional.) along the flank of the Uncompahgre uplift.

  18. Distribution, population density, and status of sympatric cercopithecids in the Campo-Ma'an area, Southwestern Cameroon.

    PubMed

    Matthews, Adele; Matthews, Andreas

    2002-07-01

    A study on species composition, distribution, and population density of cercopithecids in the Campo-Ma'an area, Southwestern Cameroon, was undertaken from December 1997 until August 2000. A total of 665.5 km of line transects was used for the census. Thirteen diurnal primate species including five endangered species (Gorilla g. gorilla, Pan troglodytes, Mandrillus sphinx, Colobus satanas, Cercocebus torquatus) were recorded in the Campo Forest, the greatest part of which is a logging concession. Cercopithecus nictitans (1.43 groups/km2), C. cephus (1.13 groups/km2), C. pogonias (0.81 groups/km2), and C. torquatus (0.51 groups/km2) occurred at medium frequencies compared to figures from other Central African study sites. Mandrill densities estimated (0.27 groups/km2) show that the area is very important for the conservation of this rare species. Guenon densities found inside areas with a high level of human activities did not differ significantly from densities estimated in areas with a lower level of human activities. C. torquatus densities were significantly higher in the areas with a low level of human disturbance and encounter rates with Lophocebus albigena also indicate a preference of less disturbed areas. Mangabeys are thus likely to be adversely affected by human activities in the area. In the Ma'an Forest, which has not been logged yet, ten species were confirmed. The population densities of two guenons (C. nictitans and C. cephus) were estimated to be twice as high in the unlogged forest area as compared to the logged forest of Campo. Other species are rarer in the Ma'an Forest than in the Campo Forest. Although mangabeys are adversely affected by human activities, the results still indicate that selective logging may be compatible with the conservation of cercopithecids, if a reduced damage logging concept and antipoaching measures are implemented. Increased hunting activities following logging operations will definitely have a negative longterm impact on

  19. Great Basin paleontological database

    USGS Publications Warehouse

    Zhang, N.; Blodgett, R.B.; Hofstra, A.H.

    2008-01-01

    The U.S. Geological Survey has constructed a paleontological database for the Great Basin physiographic province that can be served over the World Wide Web for data entry, queries, displays, and retrievals. It is similar to the web-database solution that we constructed for Alaskan paleontological data (www.alaskafossil.org). The first phase of this effort was to compile a paleontological bibliography for Nevada and portions of adjacent states in the Great Basin that has recently been completed. In addition, we are also compiling paleontological reports (Known as E&R reports) of the U.S. Geological Survey, which are another extensive source of l,egacy data for this region. Initial population of the database benefited from a recently published conodont data set and is otherwise focused on Devonian and Mississippian localities because strata of this age host important sedimentary exhalative (sedex) Au, Zn, and barite resources and enormons Carlin-type An deposits. In addition, these strata are the most important petroleum source rocks in the region, and record the transition from extension to contraction associated with the Antler orogeny, the Alamo meteorite impact, and biotic crises associated with global oceanic anoxic events. The finished product will provide an invaluable tool for future geologic mapping, paleontological research, and mineral resource investigations in the Great Basin, making paleontological data acquired over nearly the past 150 yr readily available over the World Wide Web. A description of the structure of the database and the web interface developed for this effort are provided herein. This database is being used ws a model for a National Paleontological Database (which we am currently developing for the U.S. Geological Survey) as well as for other paleontological databases now being developed in other parts of the globe. ?? 2008 Geological Society of America.

  20. Apollo Basin, Moon: Estimation of Impact Conditions

    NASA Astrophysics Data System (ADS)

    Echaurren, J. C.

    2015-07-01

    The Apollo Basin is a, pre-Nectarian, multi-ring basin located within the large South Pole-Aitken Basin (SPA). Multispectral data from both Galileo and Clementine showed that the composition of materials in Apollo is distinct…

  1. Hydrocarbon associations in evaporite basins

    SciTech Connect

    Warren, J.

    1988-01-01

    Evaporite deposition today is not representative of the diversity of scale of evaporites of the past. Ancient evaporites were deposited in two main settings: platform wide or basin wide. Platform evaporites were composed of relatively thin stratiform units (usually <5-10 m thick) deposited on either ramps or behind rimmed shelves. Basinal evaporites were deposited as thick bedded units 10s to 100s of m thick, and laid down in 4 main tectonic settings--rift, collision, transform, and intracratonic. Basins could be further subdivided into three main depositional settings: deep basin-shallow water, deep basin-deep water, and shallow basin-shallow water. Thick basinal salts were remobilized into salt structures in all tectonic settings except intracratonic. Salt flow was due to inherent instability and differential loading in tectonically active settings. Hydrocarbon accumulations associated with these various platforms and basins followed a predictable, but not mutually exclusive, pattern related to the classification of evaporite settings presented in this paper. Reservoirs in platform and ramp settings tended to be of two types--depositional and diagenetic--with most of the diagenesis following patterns predicted by the porosity and plumbing established at or soon after evaporite emplacement. Ramp reservoirs were almost always found in Zone Y, while shelf reservoirs were most common in the grainstone shoals associated with rim or island-crest facies, or their dolomitized equivalents. Reservoirs associated with basinal evaporites were also depositional or diagenetic. Depositional reservoirs were almost all related to topography present during deposition of the carbonates in the basin, often immediately preceding or just beginning evaporitic conditions in the basin.

  2. Controls of asymmetrical opening on rift and sag basins of South Atlantic conjugate margins: Insights from gravity transects and mapping using grids of seismic reflection data

    NASA Astrophysics Data System (ADS)

    Loureiro, P.; Mann, P.

    2015-12-01

    A recent model by Brune et al. (2014) explains the asymmetrical, conjugate margins of the South Atlantic as the result of passive rift migration with sequential normal faulting during early continental breakup. The onset of continental rifting in the South Atlantic began in the Valanginian about 138 Ma. Flood basalts - originating from the eruption of the Tristan Da Cunha plume on both conjugate margins - have been dated between 138-128 Ma and indicating a transition from passive rifting controlled by plate motions to active rifting controlled by a mantle plume. Using seven 2D gravity transects ranging from 200-1000 km in length, we identify variations in crustal thickness and depth to Moho for conjugate margins in Brazil and Angola. Low pass filters applied to a regional satellite derived gravity grid reveal now inactive, sequential normal faults. The modeled gravity transects refine the extent of hyperextended continental crust and allow for the identification of hanging-wall/ footwall relationships. For the Santos-Namibe conjugate margin, we propose that the Santos basin is the footwall of an asymmetrical rift system spanning a 200-km-wide zone and that the Namibe basin is the hanging wall with a 125-km-wide rift. For the Campos-Benguela conjugate margin 400 km to the north, we propose the Campos basin is the hanging wall with a 150-km-wide rift zone. Well data shows that a thicker carbonate sag basin (135- 325 m) and overlying salt basin (up to 2 km) are associated with the footwall blocks of Kwanza and Santos while thinner carbonate sag basins (15-75 m) and overlying salt (up to 1.5 km) are associated with hanging wall blocks in accord with model predictions for early opening.

  3. 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.

  4. Foreland basins and fold belts

    SciTech Connect

    Macqueen, R.W.; Leckie, D.A. )

    1992-01-01

    The papers in this book describe six foreland basins and fold belts in terms of their regional setting, stratigraphy, tectonics, and structure, and their oil and gas systems. All of the basins show general similarities, but each differs significantly in detail from the others, posing something of a problem in terms of arriving at a 'typical' foreland basin and fold belt. Some are major hydrocarbon producers; others are not. The major characteristics of the six foreland basins and fold belts are summarized in Tables 1 through 5, which provide a convenient means of comparing and contrasting these basins and their hydrocarbon resources. The Western Canada foreland basin and fold belt serves as the type example for several reasons. These include: its setting and clear relationship to a major orogene of Mesozoic-Cenozoic age; the fact that it is uncomplicated by later overprinting, segmentation, or cover rocks unlike the Ouachita, Eastern Venezuela, and U.S. Rocky Mountain foreland basins and fold belts); the fact that there is a large volume of publicly available data on the basin and an active exploration and research community; and the fact that it has reasonable oil and gas reserves in a well-defined stratigraphic framework.

  5. Hydrocarbon associations in evaporite basins

    SciTech Connect

    Warren, J.

    1988-02-01

    Evaporite deposition today is not representative of the diversity or scale of evaporites of the past. Ancient evaporites were deposited in two main settings: platform wide or basin wide. Platform evaporites were composed of relatively thin stratiform units (usually <5-10 m thick) deposited on either ramps or behind rimmed shelves. Basinal evaporites were deposited as thick bedded units 10s to 100s of m thick, and laid down in 4 main tectonic settings - rift, collision, transform, and intracratonic. Basins could be further subdivided into three main depositional settings: deep basin-shallow water, deep basin-deep water, and shallow basin-shallow water. Thick basinal salts were remobilized into salt structures in all tectonic settings except intracratonic. Salt flow was due to inherent instability and differential loading in tectonically active settings. Hydrocarbon accumulations associated with these various platforms and basins followed a predictable, but not mutually exclusive, pattern related to the classification of evaporite settings presented in this paper. Reservoirs in platform and ramp settings tended to be of two types - depositional and diagenetic - with most of the diagenesis following patterns predicted by the porosity and plumbing established at or soon after evaporite emplacement.

  6. Ichnofabric and basin analysis

    SciTech Connect

    Bottjer, D.J. ); Droser, M.L. )

    1991-06-01

    Utilization of ichnofabric indices for measuring recorded extent of bioturbation allows comparative studies of ichnofabric between different facies. In vertical sequences, measurements of ichnofabric indices can be normalized to percent of the total thickness measured for each ichnofabric index. These data can be presented as histograms, or ichnograms, when measurements are from strata deposited in a single genetically-defined sedimentary environment. Ichnograms can be used in conjunction with ichnofacies analysis to present a more complete summary of bioturbation in a sedimentary unit. Using a knowledge of the factors which contribute towards producing ichnofabric in different sedimentary environments, the range of possible ichnograms for any environment can be modeled. In addition to ichnograms, an average ichnofabric index also can be calculated as a useful summary characterization of the extent of bioturbation recorded in a sedimentary unit. Through measurement of ichnofabric indices, construction of ichnograms, and calculation of average ichnofabric index, broad-scale summary data are produced that can allow a more complete understanding of the physical and biological dynamics of sedimentary basins, especially when employed in conjunction with other basin analysis approaches.

  7. New Maturin basin, Venezuela

    SciTech Connect

    Martinez, A.R. )

    1989-09-01

    The Maturin basin of eastern Venezuela is an outstanding example of the historical logic of exploration concepts progressively woven into large-scale commercial development. Exploitation of natural asphalt in the basin started with the end of the 19th century. Geological reconnaissance in a systematic way started in 1911; first oil field, Guanoco, was discovered August 15, 1913; first seismic survey was shot in 1934; first giant oil field, Quiriquire, was discovered June 1, 1928. A well completed January 6, 1936, went through a very heavy and viscous tar interval, non-exploitable at the time, the first in the Orinoco Belt field; the preliminary geological evaluation of the 13,000 km{sup 2} accumulation started in 1967, but was done in earnest during 1979-1983. Only one well had been drilled deeper than 5,200 m in 1985, but then for the contrast, the El Furrial trend with many deep giant light crude oil fields was discovered in 1986.

  8. Advanced Chemistry Basins Model

    SciTech Connect

    Blanco, Mario; Cathles, Lawrence; Manhardt, Paul; Meulbroek, Peter; Tang, Yongchun

    2003-02-13

    The objective of this project is to: (1) Develop a database of additional and better maturity indicators for paleo-heat flow calibration; (2) Develop maturation models capable of predicting the chemical composition of hydrocarbons produced by a specific kerogen as a function of maturity, heating rate, etc.; assemble a compositional kinetic database of representative kerogens; (3) Develop a 4 phase equation of state-flash model that can define the physical properties (viscosity, density, etc.) of the products of kerogen maturation, and phase transitions that occur along secondary migration pathways; (4) Build a conventional basin model and incorporate new maturity indicators and data bases in a user-friendly way; (5) Develop an algorithm which combines the volume change and viscosities of the compositional maturation model to predict the chemistry of the hydrocarbons that will be expelled from the kerogen to the secondary migration pathways; (6) Develop an algorithm that predicts the flow of hydrocarbons along secondary migration pathways, accounts for mixing of miscible hydrocarbon components along the pathway, and calculates the phase fractionation that will occur as the hydrocarbons move upward down the geothermal and fluid pressure gradients in the basin; and (7) Integrate the above components into a functional model implemented on a PC or low cost workstation.

  9. Estancia Basin dynamic water budget.

    SciTech Connect

    Thomas, Richard P.

    2004-09-01

    The Estancia Basin lies about 30 miles to the east of Albuquerque, NM. It is a closed basin in terms of surface water and is somewhat isolated in terms of groundwater. Historically, the primary natural outlet for both surface water and groundwater has been evaporation from the salt lakes in the southeastern portion of the basin. There are no significant watercourses that flow into this basin and groundwater recharge is minimal. During the 20th Century, agriculture grew to become the major user of groundwater in the basin. Significant declines in groundwater levels have accompanied this agricultural use. Domestic and municipal use of the basin groundwater is increasing as Albuquerque population continues to spill eastward into the basin, but this use is projected to be less than 1% of agricultural use well into the 21st Century. This Water Budget model keeps track of the water balance within the basin. The model considers the amount of water entering the basin and leaving the basin. Since there is no significant surface water component within this basin, the balance of water in the groundwater aquifer constitutes the primary component of this balance. Inflow is based on assumptions for recharge made by earlier researchers. Outflow from the basin is the summation of the depletion from all basin water uses. The model user can control future water use within the basin via slider bars that set values for population growth, water system per-capita use, agricultural acreage, and the types of agricultural diversion. The user can also adjust recharge and natural discharge within the limits of uncertainty for those parameters. The model runs for 100 years beginning in 1940 and ending in 2040. During the first 55 years model results can be compared to historical data and estimates of groundwater use. The last 45 years are predictive. The model was calibrated to match to New Mexico Office of State Engineer (NMOSE) estimates of aquifer storage during the historical period by

  10. Thermal history of Michigan basin

    SciTech Connect

    Cercone, K.R.

    1984-02-01

    The elevated organic maturity observed in shallowly buried units from the Michigan basin implies that higher temperatures and thicker overburdens once existed in the basin. Evidence from sediment-accumulation rates, regional dips, and maturity of Pennsylvanian-age coals suggests that up to 1,000 m of sediment were removed by erosion prior to the Late Jurassic, when the basin became stable. Geothermal gradients during Paleozoic basin subsidence probably ranged from 35/sup 0/ to 45/sup 0/ C/ km in contrast to the average present value of 25/sup 0/ C/km. Depths to the top of the oil window ranged from 1,900 to 2,300 m during the Paleozoic. Post-Pennsylvanian erosional uplift and further thermal maturation of the basin have combined to raise the top of the oil window to its present level of 500 m.

  11. Stratigraphic modeling of sedimentary basins

    SciTech Connect

    Aigner, T. ); Lawrence, D.T. )

    1990-11-01

    A two-dimensional stratigraphic forward model has been successfully applied and calibrated in clastic, carbonate, and mixed clastic/carbonate regimes. Primary input parameters are subsidence, sea level, volume of clastics, and carbonate growth potential. Program output includes sequence geometries, facies distribution lithology distribution, chronostratigraphic plots, burial history plots, thermal and maturity histories, and crossplots. The program may be used to predict reservoir distribution, to constrain interpretations of well and seismic data, to rapidly test exploration scenarios in frontier basins, and to evaluate the fundamental controls on observed basin stratigraphy. Applications to data sets from Main Pass (US Gulf Coast), Offshore Sarawak (Malaysia), Rub'al Khali basin (Oman), Paris basin (France), and Baltimore Canyon (US East Coast) demonstrate that the program can be used to simulate stratigraphy on a basin-wide scale as well as on the scale of individual prospects.

  12. The deep Ionian Basin revisited

    NASA Astrophysics Data System (ADS)

    Tugend, Julie; Chamot-Rooke, Nicolas; Arsenikos, Stavros; Frizon de Lamotte, Dominique; Blanpied, Christian

    2016-04-01

    The deep Eastern Mediterranean Basins (Ionian and Herodotus) are characterized by thick sedimentary sequences overlying an extremely thinned basement evidenced from different geophysical methods. Yet, the nature of the crust (continental or oceanic) and the timing of the extreme crustal and lithosphere thinning in the different sub-basins remain highly controversial, casting doubts on the tectonic setting related to the formation of this segment of the North Gondwana paleo-margin. We focus on the Ionian Basin located at the western termination of the Eastern Mediterranean with the aim of identifying, characterizing and mapping the deepest sedimentary sequences. We present tentative age correlations relying on calibrations and observations from the surrounding margins and basins (Malta shelf and Escarpment, Cyrenaica margin, Sirte Basin, Apulian Platform). Two-ship deep refraction seismic data (Expanding Spread Profiles from the PASIPHAE cruise) combined with reprocessed reflection data (from the ARCHIMEDE survey) enabled us to present a homogeneous seismic stratigraphy across the basin and to investigate the velocity structure of its basement. Based on our results, and on a review of geological and geophysical observations, we suggest an Upper Triassic-Early Dogger age for the formation of the deep Ionian Basin. The nature of the underlying basement remains uncertain, both highly-thinned continental and slow-spreading type oceanic crust being compatible with the available constraints. The narrow size and relatively short-lived evolution of the Ionian Basin lead us to suggest that it is more likely the remnant of an immature oceanic basin than of a stable oceanic domain. Eventually, upscaling these results at the scale of the Eastern Mediterranean Basins highlights the complex interaction observed between two propagating oceans: The Central Atlantic and Neo-Tethys.

  13. RESERVES IN WESTERN BASINS PART IV: WIND RIVER BASIN

    SciTech Connect

    Robert Caldwell

    1998-04-01

    Vast quantities of natural gas are entrapped within various tight formations in the Rocky Mountain area. This report seeks to quantify what proportion of that resource can be considered recoverable under today's technological and economic conditions and discusses factors controlling recovery. The ultimate goal of this project is to encourage development of tight gas reserves by industry through reducing the technical and economic risks of locating, drilling and completing commercial tight gas wells. This report is the fourth in a series and focuses on the Wind River Basin located in west central Wyoming. The first three reports presented analyses of the tight gas reserves and resources in the Greater Green River Basin (Scotia, 1993), Piceance Basin (Scotia, 1995) and the Uinta Basin (Scotia, 1995). Since each report is a stand-alone document, duplication of language will exist where common aspects are discussed. This study, and the previous three, describe basin-centered gas deposits (Masters, 1979) which contain vast quantities of natural gas entrapped in low permeability (tight), overpressured sandstones occupying a central basin location. Such deposits are generally continuous and are not conventionally trapped by a structural or stratigraphic seal. Rather, the tight character of the reservoirs prevents rapid migration of the gas, and where rates of gas generation exceed rates of escape, an overpressured basin-centered gas deposit results (Spencer, 1987). Since the temperature is a primary controlling factor for the onset and rate of gas generation, these deposits exist in the deeper, central parts of a basin where temperatures generally exceed 200 F and drill depths exceed 8,000 feet. The abbreviation OPT (overpressured tight) is used when referring to sandstone reservoirs that comprise the basin-centered gas deposit. Because the gas resources trapped in this setting are so large, they represent an important source of future gas supply, prompting studies to

  14. Diversity in bee (Hymenoptera: Apoidea) and social wasp (Hymenoptera: Vespidae, Polistinae) community in "campos rupestres", Bahia, Brazil.

    PubMed

    da Silva-Pereira, Vivane; Santos, Gilberto M M

    2006-01-01

    Hymenoptera such as bees and social wasps are regular floral visitors in "campos rupestres" vegetation. A community of bees and social wasps was studied during floral visitation in an area of "campos rupestres", at Chapada Diamantina, BA, Brazil, from September 2001 to April 2002. The community was described in relation to diversity, evenness, and dominance rank, considering the individuals abundance (H' = 2.14/ J' = 0.55) and biomass (H' = 2.34/ J' = 0.60). Thirty nine bee (588 individuals/ 15.742 g) and 11 social wasp species (52 individuals/ 2.156 g) were collected, being the first report of social wasps for the Brazilian "campos rupestres". The main species regarding number of individuals were Trigona spinipes (Fabricius), Apis mellifera L., Frieseomelitta francoi (Moure), and Bombus brevivillus Franklin. About 48% of the species were represented by a single individual. There was an inversion in the dominance rank when the species biomass was considered. B. brevivillus, A. mellifera, T spinipes, and other species represented by 15 individuals or less, such as the social wasps Synoeca cyanea (Olivier), Polistes canadensis (L.) and Myschocyttarus drewseni (Saussure), and the bees Eufriesea nigrohirta (Friese), Xylocopa grisescens Lepeletier and Megachile (Pseudocentron) sp.l were the predominant species. The use of biomass in diversity analysis permitted to detect differences in the relative contribution of species in hierarchy dominance. The comparison between bee faunas from different areas indicates a large similarity of the sampled fauna in Palmeiras (Bahia State) with neighboring ecosystems, although with low values of similarity. PMID:17348126

  15. The Sondalo gabbro contact aureole (Campo unit, Eastern Alps): implications for mid-crustal mafic magma emplacement

    NASA Astrophysics Data System (ADS)

    Petri, B.; Mohn, G.; Štípská, P.; Schulmann, K.; Manatschal, G.

    2016-05-01

    Contact aureoles rimming plutonic rocks are the locus of metamorphism and deformations witnessing magma emplacement mechanisms in the crust. In this study, structural and petrological observations are combined to mineral equilibria modelling to unravel the polyphase tectono-metamorphic history of the Permian Sondalo gabbro and its host rock, the Campo unit (Eastern Alps). The Campo unit consists of Grt-St-Ms-Bt-Pl-Qtz ± Sil ± And ± Crd mica schists attesting of a Carboniferous prograde P- T path, reaching 6 kbar/600 °C and subsequently 5.6 kbar/650 °C. This metamorphism is coeval with the formation of a sub-vertical NE-SW trending foliation (S1) and its overprint by a sub-vertical NW-SE trending foliation (S2). The heat brought by the Permian intrusives subsequently caused heating of the Campo unit at around 3-4 kbar/540 °C reflected by regional static crystallization of cordierite and andalusite porphyroblasts. During the intrusion of the Sondalo gabbro, thermal peak conditions are recorded by Grt-Sil-Spl-Crd-Ilm granulitic xenoliths at ~5.5 kbar/930 °C, subsequently exhumed at ~4 kbar during the development of a new foliation (S3). This foliation is localized around the pluton and moderately dips away from the centre of the pluton. In the migmatitic contact aureole, Grt-Sil-Bt-Pl-Qtz-Ilm and Grt-Sil-Crd-Spl-Bt-Kfs-Ilm residual rocks bear the new foliation (S3) and document a decompression from 6 kbar/750 °C to 5 kbar/725 °C and from 5.2 kbar/800 °C to reach 4.8 kbar/770 °C, respectively. The P- T- d paths recorded by the host rock and the xenoliths point to a two-step magma emplacement. First the Sondalo gabbro intruded the Campo unit causing heating of the host rock without deformation at 3-4 kbar. Second, the ductile flow along the pluton margins developed a new foliation (S3) during exhumation of the pluton and its immediate contact aureole from 6 to 4 kbar. Altogether, it indicates a progressive increase in mechanical coupling between the pluton

  16. 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.

  17. K-Basins design guidelines

    SciTech Connect

    Roe, N.R.; Mills, W.C.

    1995-06-01

    The purpose of the design guidelines is to enable SNF and K Basin personnel to complete fuel and sludge removal, and basin water mitigation by providing engineering guidance for equipment design for the fuel basin, facility modifications (upgrades), remote tools, and new processes. It is not intended to be a purchase order reference for vendors. The document identifies materials, methods, and components that work at K Basins; it also Provides design input and a technical review process to facilitate project interfaces with operations in K Basins. This document is intended to compliment other engineering documentation used at K Basins and throughout the Spent Nuclear Fuel Project. Significant provisions, which are incorporated, include portions of the following: General Design Criteria (DOE 1989), Standard Engineering Practices (WHC-CM-6-1), Engineering Practices Guidelines (WHC 1994b), Hanford Plant Standards (DOE-RL 1989), Safety Analysis Manual (WHC-CM-4-46), and Radiological Design Guide (WHC 1994f). Documents (requirements) essential to the engineering design projects at K Basins are referenced in the guidelines.

  18. KE Basin Sludge Flocculant Testing

    SciTech Connect

    Schmidt, Andrew J.; Hallen, Richard T.; Muzatko, Danielle S.; Gano, Sue

    2004-06-23

    In the revised path forward and schedule for the K Basins Sludge Retrieval and Disposal Project, the sludge in K East (KE) Basin will be moved from the floor and pits and transferred to large, free-standing containers located in the pits (so as to isolate the sludge from the basin). When the sludge is pumped into the containers, it must settle fast enough and clarify sufficiently that the overflow water returned to the basin pool will not cloud the water or significantly increase the radiological dose rate to the operations staff as a result of increased suspended radioactive material. The approach being evaluated to enhance sludge settling and speed the rate of clarification is to add a flocculant to the sludge while it is being transferred to the containers. In February 2004, seven commercial flocculants were tested with a specific K Basin sludge simulant to identify those agents that demonstrated good performance over a broad range of slurry solids concentrations. From this testing, a cationic polymer flocculant, Nalco Optimer 7194 Plus (7194+), was shown to exhibit superior performance. Related prior testing with K Basin sludge and simulant in 1994/1996 had also identified this agent as promising. In March 2004, four series of jar tests were conducted with 7194+ and actual KE Basin sludge (prepared by combining selected archived KE sludge samples). The results from these jar tests show that 7194+ greatly improves settling of the sludge slurries and clarification of the supernatant.

  19. Comparative analysis of post-breakup basin evolution along the South-American and South-African margins, southern Atlantic

    NASA Astrophysics Data System (ADS)

    Strozyk, F.; Back, S.; Kukla, P. A.

    2012-04-01

    Recently, considerable attempts have been made to compare the sedimentary basin evolution and the associated tectonic framework on both sides of the South-Atlantic. However, yet there are still unresolved questions concerning the tectono-sedimentary styles of margin basin evolution that markedly differ from north to south. Amongst the most striking observations is that multiple phases of uplift and subsidence are recorded after the break-up of the southern South Atlantic margin segment on both sides of the Florianopolis-Walvis Ridge volcanic complex, features that are regarded as atypical when compared to published examples of other post-breakup margin successions. Adding to the heterogeneity of the system, the northernmost segment of the South Atlantic rift and salt basins is also characterized by a pronounced asymmetry, with the Brazilian margin now comprising narrower and deeper rift basins with less salt than the Congo-Gabon conjugate margin. This project deals with a large-scale comparison of this very different post-breakup tectono-stratigraphic development of the southern and northern South American and African continental margins that both record thick post-rift sedimentary successions. To gain detail of the basin margin evolution, we focus on a regional comparison between the post-breakup records archived in the large offshore southern Brazil basins (Pelotas, Santos, Campos) and the post-breakup continental margin successions of offshore Namibia (e.g. Orange Basin) and southern Angola (e.g. Kwanza Basin). A tectonic-stratigraphic comparison of representative geological transects provides a comprehensive basin-to-basin documentation of key factors influencing margin development which include the subsidence development through time, the sediment (in-)flux and storage patterns and the respective type of basin fill (e.g. salt vs. non-salt systems; carbonate-rich vs. clastics-dominated systems). Data from the salt-prone areas offshore South America and southern

  20. Basin development and petroleum potential of offshore Otway basin, Australia

    SciTech Connect

    Williamson, P.E.; O'Brien, G.W.; Swift, M.G.; Scherl, A.S.; Marlow, M.S.; Exon, N.F.; Falvey, D.A.; Lock, J.; Lockwood, K.

    1987-05-01

    The Bass Strait region in southeastern Australia contains three sedimentary basins, which are, from east to west, the Gippsland, Bass, and Otway basins. The offshore Gippsland basin is Australia's most prolific petroleum-producing province and supplies over 90% of the country's production. In contrast, exploration has been unsuccessful in the offshore portion of the Otway basin; 17 wells have been drilled, and although shows of oil and gas have been common, no commercial discoveries have been made. Many of these wells, drilled in the 1960s and 1970s, were sited using poor-quality seismic data and, as a consequence, were frequently off structure. Seismic data quality has, however, improved significantly in recent years. The present study by the Australian Bureau of Mineral Resources (BMR) involved the collection, in the offshore Otway basin, of 3700 km of high-quality, 48-channel seismic reflection data by the BMR research vessel R/V Rig Seismic. These data have been integrated with existing industry seismic data, well data, limited dredged material, and geohistory analyses in a framework study of basin development and hydrocarbon potential in this under-explored area. The offshore Otway basin extends 500 km along the southern coastline and is typically 50 km wide in water depths of less than 200 m. It contains up to 10 km of predominantly late Mesozoic to early Cenozoic sediments, which are overlain by a thin sequence of middle to late Tertiary shelf carbonates. It has been divided into three main structural elements: the Mussel Platform in the east, the central Voluta Trough, and the Crayfish Platform in the west. The basin was initiated at the end of the Jurassic as part of the Bassian rift. Up to 6 km of Lower Cretaceous sediments were deposited prior to breakup at the end of the Early Cretaceous and the onset of sea-floor spreading between Australia and Antarctica.

  1. CAMPO, SCR_FIND and CHC_FIND: a suite of web tools for computational structural biology.

    PubMed

    Paiardini, Alessandro; Bossa, Francesco; Pascarella, Stefano

    2005-07-01

    The identification of evolutionarily conserved features of protein structures can provide insights into their functional and structural properties. Three methods have been developed and implemented as WWW tools, CAMPO, SCR_FIND and CHC_FIND, to analyze evolutionarily conserved residues (ECRs), structurally conserved regions (SCRs) and conserved hydrophobic contacts (CHCs) in protein families and superfamilies, on the basis of their 3D structures and the homologous sequences available. The programs identify protein segments that conserve a similar main-chain conformation, compute residue-to-residue hydrophobic contacts involving only apolar atoms common to all the 3D structures analyzed and allow the identification of conserved amino-acid sites among protein structures and their homologous sequences. The programs also allow the visualization of SCRs, CHCs and ECRs directly on the superposed structures and their multiple structural and sequence alignments. Tools and tutorials explaining their usage are available at http://schubert.bio.uniroma1.it/SCR_FIND, http://schubert.bio.uniroma1.it/CHC_FIND and http://schubert.bio.uniroma1.it/CAMPO.

  2. 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.

  3. Principles of Sedimentary Basin Analysis

    NASA Astrophysics Data System (ADS)

    Stanton, Robert J., Jr.

    Basin analysis is the ultimate act of synthesis in stratigraphy. Its objective is to weave together the diverse strands of information in order to portray the tectonic evolution of a basin, its filling with sediments in a broad range of depositional environments, the subsequent diagenesis and lithification of these sediments, and the localization therein of mineral and petroleum resources. Thus, although the primary emphasis in basin analysis is stratigraphic and sedimentologic in nature, paleontologic, tectonic, and geophysical data, among others, are also integral components of the effort. It is scientifically challenging and, in practical terms, forms the foundation for the exploration for strata-bound resources. The wide range of topics that must be incorporated into a basin analysis requires that it be a group project of specialists and means that it is a difficult subject to teach or to present in a book.

  4. 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

  5. 77 FR 45653 - Yakima River Basin Conservation Advisory Group; Yakima River Basin Water Enhancement Project...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-01

    ... Bureau of Reclamation Yakima River Basin Conservation Advisory Group; Yakima River Basin Water... on the structure, implementation, and oversight of the Yakima River Basin Water Conservation Program... of the Water Conservation Program, including the applicable water conservation guidelines of...

  6. Comparison of predicted binders in Rhipicephalus (Boophilus) microplus intestine protein variants Bm86 Campo Grande strain, Bm86 and Bm95.

    PubMed

    Andreotti, Renato; Pedroso, Marisela S; Caetano, Alexandre R; Martins, Natália F

    2008-01-01

    This paper reports the sequence analysis of Bm86 Campo Grande strain comparing it with Bm86 and Bm95 antigens from the preparations TickGardPLUS and Gavac, respectively. The PCR product was cloned into pMOSBlue and sequenced. The secondary structure prediction tool PSIPRED was used to calculate alpha helices and beta strand contents of the predicted polypeptide. The hydrophobicity profile was calculated using the algorithms from the Hopp and Woods method, in addition to identification of potential MHC class-I binding regions in the antigens. Pair-wise alignment revealed that the similarity between Bm86 Campo Grande strain and Bm86 is 0.2% higher than that between Bm86 Campo Grande strain and Bm95 antigens. The identities were 96.5% and 96.3% respectively. Major suggestive differences in hydrophobicity were predicted among the sequences in two specific regions. PMID:18823577

  7. Flexural analysis of two broken foreland basins; Late Cenozoic Bermejo basin and Early Cenozoic Green River basin

    SciTech Connect

    Flemings, P.B.; Jordan, T.E.; Reynolds, S.

    1986-05-01

    Lithospheric flexure that generates basin in a broke foreland setting (e.g., the Laramide foreland of Wyoming) is a three-dimensional system related to shortening along basin-bounding faults. The authors modeled the elastic flexure in three dimensions for two broken foreland basins: the early Cenozoic Green River basin and the analogous late Cenozoic Bermejo basin of Argentina. Each basin is located between a thrust belt and a reverse-fault-bounded basement uplift. Both basins are asymmetric toward the basement uplifts and have a central basement high: the Rock Springs uplift and the Pie de Palo uplift, respectively. The model applies loads generated by crustal thickening to an elastic lithosphere overlying a fluid mantle. Using the loading conditions of the Bermejo basin based on topography, limited drilling, and reflection and earthquake seismology, the model predicts the current Bermejo basin geometry. Similarly, flexure under the loading conditions in the Green River basin, which are constrained by stratigraphy, well logs, and seismic profiling and summed for Late Cretaceous (Lance Formation) through Eocene (Wasatch Formation), successfully models the observed geometry of the pre-Lance surface. Basin depocenters (> 4 km for the Green River basin; > 7 km for the Bermejo basin) and central uplifts are predicted to result from constructive interference of the nonparallel applied loads. Their Bermejo model implies that instantaneous basin geometry is successfully modeled by crustal loading, whereas the Green River basin analysis suggests that basin evolution can be modeled over large time steps (e.g., 20 Ma). This result links instantaneous basin geometry to overall basin evolution and is a first step in predicting stratigraphic development.

  8. Viscoelastic Relaxation of Lunar Basins

    NASA Astrophysics Data System (ADS)

    Mohit, P. S.; Phillips, R. J.

    2004-12-01

    The large lunar impact basins provide a unique glimpse into early lunar history. Here we investigate the possibility that the relief of the oldest lunar basins (with the exception of South-Pole Aitken) has decayed through viscous relaxation. We identify nine ancient multi-ring basins with very low relief and low-amplitude Bouguer and free-air gravity anomalies. The characteristics of these basins are consistent with either 1) relaxation of topographic relief by ductile flow (e.g. Solomon et al., 1982) or 2) obliteration of basin topography during crater collapse immediately following impact. Both scenarios require that the basins formed early in lunar history, when the Moon was hot. The latter possibility appears to be unlikely due to the great topographic relief of South Pole-Aitken basin (SPA), the largest and oldest impact basin on the Moon (with the possible exception of the putative Procellarum basin; Wilhelms, 1987). On the other hand, the thin crust beneath SPA may not have allowed ductile flow in its lower portions, even for a hot Moon, implying that a thicker crust is required beneath other ancient basins for the hypothesis of viscous relaxation to be tenable. Using a semi-analytic, self-gravitating viscoelastic model, we investigate the conditions necessary to produce viscous relaxation of lunar basins. We model topographic relaxation for a crustal thickness of 30 km, using a dry diabase flow law for the crust and dry olivine for the mantle. We find that the minimum temperature at the base of the crust (Tb) permitting nearly complete relaxation of topography by ductile flow on a timescale < 108 yrs is 1400 K, corresponding to a heat flow of 55mW/m2, into the crust. Ductile flow in the lower crust becomes increasingly difficult as the crustal thickness decreases. The crust beneath SPA, thinned by the impact, is only 15-20 km thick and would require Tb ≥ 1550 K for relaxation to occur. The fact that SPA has maintained high-amplitude relief suggests that

  9. Basin modeling of Tadla basin, Morocco, for hydrocarbon potential

    SciTech Connect

    Jabour, H.; Nakayama, K.

    1988-09-01

    The Tadla basin, Morocco, is the easternmost major structural subdivision of the Meseta south of the Central Massif. After the basin remained relatively stable through the Paleozoic, movements during the Variscan orogeny divided the basin into two subbasins, a western subbasin where compressional forces formed large anticlines and an eastern subbasin where intense folding and faulting are associated with uplift and erosion. The sedimentary basin fill includes numerous organic shales, which provide the source beds. Also deposited were numerous shallow-water to continental clastics and to a lesser extent carbonates, providing several possible reservoir rocks for hydrocarbons. The results from computer modeling show that the chief formations of hydrocarbon generation are Carboniferous and Silurian. Most of these formations may have generated hydrocarbons before Variscan movements, which probably destroyed preexisting oil and gas traps. The only source rocks in the generation stage from Mesozoic to the present are the upper Visean shales. The western part of the Tadla basin was the most favorable area for the generation and maturation of hydrocarbons of the upper Visean shales. 22 figures.

  10. Paleothermometry of the Sydney Basin

    SciTech Connect

    Middleton, M.F.; Schmidt, P.W.

    1982-07-10

    Evidence from overprinting of magnetizations of Late Permian and Mesozoic rocks and from the rank of Permian coals and Mesozoic phytoclasts (coal particles) suggests that surface rocks in the Sydney Basin, eastern Australia, have been raised to temperatures of the order of 200 /sup 0/C or higher. As vitrinite reflectance, an index of coal rank or coalification, is postulated to vary predictably with temperature and time, estimates of the paleotemperatures in the Sydney Basin based on observed vitrinite reflectance measurements can be made in conjunction with reasonable assumptions about the tectonic and thermal histories of the basin. These estimates give maximum paleotemperatures of present day surface rocks in the range 60--249 /sup 0/C, depending on factors such as location in the basin, the thickness of the sediment eroded, and the maximum paleogeothermal gradient. Higher coal rank and, consequently, larger eroded thicknesses and paleogeothermal gradients occur along the eastern edge of the basin and may be related to seafloor spreading in the Tasman Sea on the basin's eastern margin. A theory of thermal activation of magnetization entailing the dependence of magnetic viscosity on the size distribution of the magnetic grains is used to obtain an independent estimate of the maximum paleotemperatures in the Sydney Basin. This estimate places the maximum paleotemperature in the range 250--300 /sup 0/C along the coastal region. Both coalification and thermal activation of magnetization models provide strong evidence of elevated paleotemperatures, which in places exceed 200 /sup 0/C, and the loss of sediment thicknesses in excess of 1 km due to erosion.

  11. Floor of Hellas Basin

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    With a diameter of roughly 2000 km and a depth of over 7 km, the Hellas Basin is the largest impact feature on Mars. Because of its great depth, there is significantly more atmosphere to peer through in order to see its floor, reducing the quality of the images taken from orbit. This THEMIS image straddles a scarp between the Hellas floor and an accumulation of material at least a half kilometer thick that covers much of the floor. The southern half of the image contains some of this material. Strange ovoid landforms are present here that give the appearance of flow. It is possible that water ice or even liquid water was present in the deposits and somehow responsible for the observed landscape. The floor of Hellas remains a poorly understood portion of the planet that should benefit from the analysis of new THEMIS data.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in

  12. Smythii basin topography and comparisons with Orientale

    NASA Technical Reports Server (NTRS)

    Strain, P. L.; El-Baz, F.

    1979-01-01

    The Smythii basin has the most extensive topographic coverage of any lunar multi-ringed basin. Topographic data are used to study the morphology and morphometry of Smythii and to make comparisons with similar basins. The depth of the basin is shown to be over 8 km, which is comparable to that of Orientale. The inner ring reaches heights of 3.4 km, while the intermediate ring exhibits little relief. Lowest points in the basin are related to mare ridges. Basin volume is estimated to be 21 million cubic kilometers. Evidence suggests that significant differences in substrate characteristics may have existed for the Smythii and Orientale impacts.

  13. Analogue models of pull-apart basins

    NASA Astrophysics Data System (ADS)

    McClay, Ken; Dooley, Tim

    1995-08-01

    Sandbox analogue models of pull-apart basins that developed in sedimentary strata above releasing steps in underlying basement faults are characterized by rhombic basins that are flat-bottomed box grabens with a subhorizontal synkinematic basin infill. Steep to nearly vertical, sigmoidal oblique-slip and segmented oblique-extensional faults are the dominant bounding structures of the pull-apart basins. Cross-basin, short-cut faults link the offset principal displacement zones that are characterized by flower structure development. The structural architectures of the physical models compare directly in form and dimensions to natural examples of strike-slip pull-apart basins.

  14. Time, Weather and Empires: The Campos Rodrigues Observatory in Lourenço Marques, Mozambique (1905-1930).

    PubMed

    Raposo, Pedro M P

    2015-07-01

    In 1905 the Campos Rodrigues Observatory (CRO) was founded in Lourenço Marques (nowadays Maputo), the capital of Mozambique, by then part of the Portuguese overseas empire. In this paper the inception and early history of the CRO are analysed in the broader context of the interwoven history of the Portuguese and British empires in Africa, and specifically with respect to the scientific relations between Mozambique and South Africa. The equipment, personnel, practices and networks involved in the inception and early development of the CRO are brought into focus in order to illustrate the problems and strategies that shaped the establishment and functioning of this observatory, which was conceived essentially as a symbol of imperial stamina and colonial prowess. It is suggested that by providing a focal point for the development of scientific relations between Mozambique and South Africa, the CRO served both Portuguese ambitions for recognition as an imperial power and the emergence of South African nationalism. PMID:26104301

  15. Time, Weather and Empires: The Campos Rodrigues Observatory in Lourenço Marques, Mozambique (1905-1930).

    PubMed

    Raposo, Pedro M P

    2015-07-01

    In 1905 the Campos Rodrigues Observatory (CRO) was founded in Lourenço Marques (nowadays Maputo), the capital of Mozambique, by then part of the Portuguese overseas empire. In this paper the inception and early history of the CRO are analysed in the broader context of the interwoven history of the Portuguese and British empires in Africa, and specifically with respect to the scientific relations between Mozambique and South Africa. The equipment, personnel, practices and networks involved in the inception and early development of the CRO are brought into focus in order to illustrate the problems and strategies that shaped the establishment and functioning of this observatory, which was conceived essentially as a symbol of imperial stamina and colonial prowess. It is suggested that by providing a focal point for the development of scientific relations between Mozambique and South Africa, the CRO served both Portuguese ambitions for recognition as an imperial power and the emergence of South African nationalism.

  16. Spotted fever group Rickettsia in Amblyomma dubitatum tick from the urban area of Campo Grande, Mato Grosso do Sul, Brazil.

    PubMed

    Matias, Jaqueline; Garcia, Marcos Valério; Cunha, Rodrigo Casquero; Aguirre, André de Abreu Rangel; Barros, Jacqueline Cavalvante; Csordas, Bárbara Guimarães; Andreotti, Renato

    2015-03-01

    Rickettsia infection of each tick was evaluated by the hemolymph test and polymerase chain reaction (PCR) targeting gltA and ompA genes. All hemolymph tests were negative and PCR of one A. dubitatum detected both Rickettsia genes. Sequence of ompA exhibited a 99% identity with Rickettsia parkeri and R. africae and a 98% identity with R. sibirica. Rickettsia of the spotted fever group in A. dubitatum is described for the first time in an urban area within the municipality of Campo Grande in the state of Mato Grosso do Sul (MS), Brazil. This finding reinforces the importance of more detailed studies to determine the role of A. dubitatum in the transmission of spotted fever agents.

  17. Spotted fever group Rickettsia in Amblyomma dubitatum tick from the urban area of Campo Grande, Mato Grosso do Sul, Brazil.

    PubMed

    Matias, Jaqueline; Garcia, Marcos Valério; Cunha, Rodrigo Casquero; Aguirre, André de Abreu Rangel; Barros, Jacqueline Cavalvante; Csordas, Bárbara Guimarães; Andreotti, Renato

    2015-03-01

    Rickettsia infection of each tick was evaluated by the hemolymph test and polymerase chain reaction (PCR) targeting gltA and ompA genes. All hemolymph tests were negative and PCR of one A. dubitatum detected both Rickettsia genes. Sequence of ompA exhibited a 99% identity with Rickettsia parkeri and R. africae and a 98% identity with R. sibirica. Rickettsia of the spotted fever group in A. dubitatum is described for the first time in an urban area within the municipality of Campo Grande in the state of Mato Grosso do Sul (MS), Brazil. This finding reinforces the importance of more detailed studies to determine the role of A. dubitatum in the transmission of spotted fever agents. PMID:25454606

  18. Stormwater detention basin sediment removal

    SciTech Connect

    Gross, W.E.

    1995-12-31

    In the past, stormwater runoff from landfills has been treated mainly by focusing on reducing the peak storm discharge rates so as not to hydraulically impact downstream subsheds. However, with the advent of stricter water quality regulations based on the Federal Clean Water Act, and the related NPDES and SPDES programs, landfill owners and operators are now legally responsible for the water quality of the runoff once it leaves the landfill site. At the Fresh Kills Landfill in New York City, the world`s largest covering over 2000 acres, landfilling activities have been underway since 1945. With the main objective at all older landfill sites having focused on maximizing the available landfill footprint in order to obtain the most possible airspace volume, consideration was not given for the future siting of stormwater basin structures. Therefore, when SCS Engineers began developing the first comprehensive stormwater management plan for the site, the primary task was to locate potential sites for all the stormwater basins in order to comply with state regulations for peak stormwater runoff control. The basins were mostly constructed where space allowed, and were sized to be as large as possible given siting and subshed area constraints. Seventeen stormwater basins have now been designed and are being constructed to control the peak stormwater runoff for the 25-year, 24-hour storm as required by New York State. As an additional factor of safety, the basins were also designed for controlled discharge of the 100-year, 24 hour storm.

  19. Inversion of Extensional Sedimentary Basins

    NASA Astrophysics Data System (ADS)

    Buiter, Susanne J. H.; Pfiffner, O. Adrian

    The evolution of extensional sedimentary basins is governed by the surrounding stress field and can, therefore, be expected to be highly sensitive to variations in these stresses. Important changes in basin geometry are to be expected in the case of an even short-lived reversal from extension to compression. We investigate the evolu- tion of fold and thrust structures which form in compression after extension, when basin forming processes have come to a complete stop. To this purpose, we use a two- dimensional, viscoplastic model and start our experiments from a pre-existing exten- sional geometry. We illustrate the sensitivity of the evolving structures to inherited extensional geometry, sedimentary and erosional processes, and material properties. One series of our model experiments involves the upper- to middle crust only in order to achieve a high detail in the basin area. We find that our results agree with examples from nature and analogue studies in, among others, the uplift and rotation of syn-rift sediments, the propagation of shear zones into the post-rift sediments and, in specific cases, the development of back-thrusts or basement short-cut faults. We test the out- come of these models by performing a second series of model simulations in which basins on a continental margin are inverted through their progressive approach of a subduction zone. These latter models are on the scale of the whole upper mantle.

  20. Water Accounting from Ungauged Basins

    NASA Astrophysics Data System (ADS)

    Bastiaanssen, W. G.; Savenije, H.

    2014-12-01

    Water scarcity is increasing globally. This requires a more accurate management of the water resources at river basin scale and understanding of withdrawals and return flows; both naturally and man-induced. Many basins and their tributaries are, however, ungauged or poorly gauged. This hampers sound planning and monitoring processes. While certain countries have developed clear guidelines and policies on data observatories and data sharing, other countries and their basin organization still have to start on developing data democracies. Water accounting quantifies flows, fluxes, stocks and consumptive use pertaining to every land use class in a river basin. The objective is to derive a knowledge base with certain minimum information that facilitates decision making. Water Accounting Plus (WA+) is a new method for water resources assessment reporting (www.wateraccounting.org). While the PUB framework has yielded several deterministic models for flow prediction, WA+ utilizes remote sensing data of rainfall, evaporation (including soil, water, vegetation and interception evaporation), soil moisture, water levels, land use and biomass production. Examples will be demonstrated that show how remote sensing and hydrological models can be smartly integrated for generating all the required input data into WA+. A standard water accounting system for all basins in the world - with a special emphasis on data scarce regions - is under development. First results of using remote sensing measurements and hydrological modeling as an alternative to expensive field data sets, will be presented and discussed.

  1. Exploration potential of offshore northern California basins

    SciTech Connect

    Bachman, S.B.; Crouch, J.K.

    1988-01-01

    A series of exploratory wells was drilled in the northern California offshore basins in the 1960s following leasing of federal tracts off northern California, Oregon, and Washington. The drilling, although encountering numerous oil shows, was considered at the time to indicate low prospectivity in an area that extended as far south as the offshore Santa Maria basin. However, subsequent major discoveries in this decade in the offshore Santa Maria basin, such as the Point Arguello field, indicate that these offshore basins may be highly prospective exploration targets. Many of the key features of Monterey production in central and southern California are also present in the offshore basins of northern California. A new 5-year leasing plan has scheduled leasing in the northern California OCS starting in early 1989. The first basins on the schedule, the Point Arena and Eel River basins, differ in some respects. The Point Arena basin is more typical of a Monterey basin, with the potential for fractured chert reservoirs and organic-rich sections, deep burial of basinal sections to enhance the generation of higher gravity oils, and complex folding and faulting. The Eel River basin is more clastic-rich in its gas-producing, onshore extension. Key questions in the Eel River basin include whether the offshore, more distal stratigraphy will include Monterey-like biogenic sediments, and whether the basin has oil potential in addition to its proven gas potential. The Outer Santa Cruz basin shares a similar stratigraphy, structure, and hydrocarbon potential with the Point Arena basin. The Santa Cruz-Bodega basin, also with a similar stratigraphy, may have less exploration potential because erosion has thinned the Monterey section in parts of the basin.

  2. Testing for Basins of Wada

    PubMed Central

    Daza, Alvar; Wagemakers, Alexandre; Sanjuán, Miguel A. F.; Yorke, James A.

    2015-01-01

    Nonlinear systems often give rise to fractal boundaries in phase space, hindering predictability. When a single boundary separates three or more different basins of attraction, we say that the set of basins has theWada property and initial conditions near that boundary are even more unpredictable. Many physical systems of interest with this topological property appear in the literature. However, so far the only approach to study Wada basins has been restricted to two-dimensional phase spaces. Here we report a simple algorithm whose purpose is to look for the Wada property in a given dynamical system. Another benefit of this procedure is the possibility to classify and study intermediate situations known as partially Wada boundaries. PMID:26553444

  3. Oil in the Malvinas Basin

    SciTech Connect

    Galeazzi, J.S.

    1996-08-01

    The Malvinas Basin is petroliferous. The main source rocks are Late Jurassic and Early Cretaceous outer shelf to basinal shales known as the Pampa Rincon and Lower Inoceramus formations. Main reservoirs are fluvial and shallow-marine sandstones of the coeval Springhill Formation. On the western flank of the basin, 17 wells drilled the Cenozoic and Mesozoic column. Three of these wells discovered hydrocarbons within the Springhill Formation, and one discovered oil in Early Paleogene sandstones. Additionally, some wells recorded shows at different levels within the stratigraphic succession. A detailed overview of the drilled portion of the basin permitted the construction of a sequence stratigraphic framework, and yielded clues on a complex history of deformation. Interpretation of facies and stratal stacking and termination patterns determined that the main reservoir and source rocks were deposited in a ramp-style depositional setting. They represent the lower transgressive phase of a Late Jurassic to Early Cretaceous megasequence deposited during the early sag stage of the basin. Alternative reservoirs to the Springhill sandstones include early Paleogene glauconitic sandstones and carbonates, and Miocene deep-water turbidites. Structural trap styles include normal fault features of Jurassic to Early Cretaceous age, and compressional and inverted positive structures due to Neogene compression. Possible combination and stratigraphic traps include: little tested onlap pinchout of Late Jurassic to Early Cretaceous and Paleogene sandstones and untested erosionally truncated Paleogene sandstones; Early Paleogene carbonate buildups and Miocene deep-water turbidite mounds. The understanding of the geology of the western Malvinas Basin is the key to success of exploration in the huge frontier surrounding areas.

  4. Origin of the earth's ocean basins

    NASA Technical Reports Server (NTRS)

    Frex, H.

    1977-01-01

    The earth's original ocean basins were mare-type basins produced 4 billion years ago by the flux of asteroid-sized objects responsible for the lunar mare basins. Scaling upwards from the observed number of lunar basins for the greater capture cross-section and impact velocity of the Earth indicates that at least 50 percent of an original global crust would have been converted to basin topography. These basins were flooded by basaltic liquids in times short compared to the isostatic adjustment time for the basin. The modern crustal dichotomy (60 percent oceanic, 40 percent continental crust) was established early in the history of the earth, making possible the later onset of plate tectonic processes. These later processes have subsequently reworked, in several cycles, principally the oceanic parts of the earth's crust, changing the configuration of the continents in the process. Ocean basins (and oceans themselves) may be rare occurrences on planets in other star systems.

  5. H-Area Seepage Basins

    SciTech Connect

    Stejskal, G.

    1990-12-01

    During the third quarter of 1990 the wells which make up the H-Area Seepage Basins (H-HWMF) monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, nonvolatile beta, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Seepage Basins are tritium, nitrate, mercury, gross alpha, nonvolatile beta, trichloroethylene (TCE), tetrachloroethylene, lead, cadmium, arsenic, and total radium.

  6. 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.

  7. Exhumation, cooling and deformation history of the necking zone of the fossil Adriatic rifted margin: the Campo/Grosina section (S-Switzerland and N-Italy)

    NASA Astrophysics Data System (ADS)

    Petri, Benoît; Mohn, Geoffroy; Wijbrans, Jan R.; Manatschal, Gianreto; Beltrando, Marco

    2016-04-01

    The Austroalpine units in SE Switzerland and N-Italy preserve remnants of the fossil Adriatic rifted margin. Notably the Campo-Grosina units represent the necking zone where major crustal thinning was accommodated during the Jurassic rifting. This contribution aims to unravel the complex tectonic evolution recorded in these units from the late Carboniferous - early Permian to the Jurassic rifting. The cooling and exhumation of the Campo and overlying Grosina units, separated by the Eita shear zone are explored by the acquisition of 40Ar/39Ar on hornblende, muscovite and biotite. New geochronological data on the Grosina unit present 40Ar/39Ar ages between 273 and 261 Ma for muscovite and between 248 and 246 Ma for biotite. The Campo unit shows clearly younger ages between 210 and 177 Ma on hornblende, between 186 and 176 Ma on muscovite and between 174 and 171 Ma on biotite. Numerous data were discarded due to frequent excess 40Ar on amphiboles, probably associated to the emplacement of the Sondalo gabbro with a high 40Ar/36Ar ratio in Permian times. These new ages, together with a compilation of existing ages obtained with different chronometers (U-Pb, Sm-Nd, Rb-Sr, K-Ar, 40Ar/39Ar) and performed on different lithologies from both the Campo and the Grosina units allow an estimation of the cooling rates for these units to be done. The new results show that both the Campo and the Grosina units underwent a cooling rate around 10°C/Ma in Permian time. The Grosina unit, being in a shallower crustal level, did not record the Jurassic cooling, reaching up to 50°C/Ma in the Campo unit. The notable difference in cooling rates between the Permian and the Jurassic events attests of a cooling without being associated to an exhumation in Permian times, whereas the Campo unit cooled rapidly in Jurassic times, due to an exhumation and an emplacement in shallow crustal levels. The latter tectonic event was likely caused by shearing along the Eita or other greenschist facies

  8. Supplementary information on K-Basin sludges

    SciTech Connect

    MAKENAS, B.J.

    1999-03-15

    Three previous documents in this series have been published covering the analysis of: K East Basin Floor and Pit Sludge, K East Basin Canister Sludge, and K West Basin Canister Sludge. Since their publication, additional data have been acquired and analyses performed. It is the purpose of this volume to summarize the additional insights gained in the interim time period.

  9. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Turning basins. 401.48 Section... TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.48 Turning basins. No vessel... the locations set out in the table to this section. Table 1. South Shore Canal: (a) Turning Basin...

  10. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Turning basins. 401.48 Section... TRANSPORTATION SEAWAY REGULATIONS AND RULES Regulations Seaway Navigation § 401.48 Turning basins. No vessel... the locations set out in the table to this section. Table 1. South Shore Canal: (a) Turning Basin...

  11. IMPROVEMENTS IN PUMP INTAKE BASIN DESIGN

    EPA Science Inventory

    Pump intake basins (or wet wells or pump sumps) designed in accordance with accepted criteria often pose many operation and maintenance problems. The report summarizes field surveys of three trench-type pump intake basins representative of 29 such basins that have been in satisfa...

  12. The Santa Terezinha-Campos Verdes emerald district, central Brazil: structural and Sm-Nd data to constrain the tectonic evolution of the Neoproterozoic Brası´lia belt

    NASA Astrophysics Data System (ADS)

    D'el-Rey Silva, Luiz José Homem; Barros Neto, Leonel de Souza

    2002-12-01

    Structural analysis coupled with Sm-Nd isotope data and a detailed description of the geology of the Santa Terezinha-Campos Verdes emerald district (Goiás State, Central Brazil) constrain the evolution of the Neoproterozoic Brası´lia belt. The area is composed of tectonic slices of Archean-Paleoproterozoic gneiss, a Meso-Neoproterozoic metavolcanic sedimentary sequence called the Santa Terezinha sequence, and crustal-derived intrusive rocks such as mylonitic (ortho)gneiss and a syntectonic porphyry granite. It underwent a Neoproterozoic greenschist facies polyphase ductile deformation (D 1-D 3). Structures indicate an event of rotational deformation along a typical frontal ramp dipping gently to the west (i.e. an event of simple shear with top to ESE relative regional movement due to a subhorizontal WNW-ESE compression). A Sm-Nd whole-rock isochron age of 577±77 Ma for the intrusive rocks constrains the timing of at least part of the deformation/metamorphism in the area. Primary and metamorphic planar structures (mainly D 1-D 2) strike SW-NE and dip at low to moderate angles to the NW in the northern part of the area. However, they gradually rotate to SSE in the central SE part, where the Peixe River synclinorium is developed. This synclinorium is also the nest of the D 2 sheath folds that control emerald ore shoots. The Santa Cruz dome is a basement-cored, major elliptic structure in the SW of the area. The Santa Terezinha sequence represents a back-arc basin that received input from the Neoproterozoic Goiás magmatic arc to the west and the São Francisco ancient continental margin to the east. The basal and upper sections of this sequence correlate, respectively, with other passive margin and back-arc sequences of the Brası´lia belt.

  13. BASIN: Beowulf Analysis Symbolic INterface

    NASA Astrophysics Data System (ADS)

    Vesperini, Enrico; Goldberg, David M.; McMillan, Stephen L. W.; Dura, James; Jones, Douglas

    2013-08-01

    BASIN (Beowulf Analysis Symbolic INterface) is a flexible, integrated suite of tools for multiuser parallel data analysis and visualization that allows researchers to harness the power of Beowulf PC clusters and multi-processor machines without necessarily being experts in parallel programming. It also includes general tools for data distribution and parallel operations on distributed data for developing libraries for specific tasks.

  14. Evolution of the Congo Basin

    NASA Astrophysics Data System (ADS)

    Glasmacher, U. A.; Bauer, F. U.; Kollenz, S.; Delvaux, D.

    2012-04-01

    The Congo Basin is one of the largest basins in the World with very little knowledge on the geological evolution as well as the oil and gas potential. In the past, oil seeps are recorded in the central part of the basin. Four sides in the Congo basin have been drilled so far. The cores of the two drill sides Dekese and Samba are located at the Musée royal de l'Afrique Centrale, Belgium. In a reconnaissance survey, we sampled both drill cores in a nearly even spacing of ~ 150 m covering the whole stratigraphy from Albian to Proterozoic. The red and green to grey sandstone samples were prepared by usual heavy minerals separation technique. Most of the samples revealed enough apatite and zircon grains for the two thermochronometric techniques fission track and (U-Th-Sm)/He. The time-temperature (t-T) evolution for the two drill locations were modelled by using the determined thermochronological data within the software code HeFTy. We tested various geological evolutionary constrains. Both techniques provide us information on the thermal and exhumation of the possible source area and on the drill location by themselves.

  15. 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.

  16. Automated basin delineation from digital terrain data

    NASA Technical Reports Server (NTRS)

    Marks, D.; Dozier, J.; Frew, J.

    1983-01-01

    While digital terrain grids are now in wide use, accurate delineation of drainage basins from these data is difficult to efficiently automate. A recursive order N solution to this problem is presented. The algorithm is fast because no point in the basin is checked more than once, and no points outside the basin are considered. Two applications for terrain analysis and one for remote sensing are given to illustrate the method, on a basin with high relief in the Sierra Nevada. This technique for automated basin delineation will enhance the utility of digital terrain analysis for hydrologic modeling and remote sensing.

  17. Use and valuation of native and introduced medicinal plant species in Campo Hermoso and Zetaquira, Boyacá, Colombia

    PubMed Central

    2013-01-01

    Background Medicinal plant species contribute significantly to folk medicine in Colombia. However, few local studies have investigated whether species used are introduced or native and whether there is a difference in importance of native and introduced medicinal plant species. The aim of the present study was to describe the use of medicinal plants within two municipalities, Campo Hermoso and Zetaquira, both in the department of Boyacá, Colombia and to assess the importance of native and introduced plants to healers, amateur healers and local people. As local healers including amateur healers have no history of introduced species our working hypotheses (H1-2) were that H1: native and introduced medicinal plant species are of equal importance and H2: healers and amateur healers do not differentiate in their preferences between native and introduced medicinal plant species. Methods Ten villages were included in the study. A combination of quantitative and qualitative methods was used including questionnaires, semi-structured interviews, in- depth interviews, and open talks. Voucher specimens were collected in home gardens and during field walks. For data analysis, we calculated use value indices and Jaccard index and tested for the above hypothesis using Spearman rank-correlation coefficients and Wilcoxon-Mann–Whitney tests. Results Eighty medicinal plant species were described by locals as the most frequently used. Of these, 78 species were taxonomically identified, distributed within 41 families and 74 genera, which included 35 native species and 43 introduced. The highest valued families were: Asteraceae, Lamiaceae, Apiaceae, Rutaceae and Verbenaceae. The species ranked highest according to their Use Values, in both municipalities, were Mentha suaveolens Ehrh., Ambrosia cumanensis Kunth, and Verbena littoralis Kunth. Introduced species were more important than native ones in Zetaquira, while there was no difference in importance in Campo Hermoso. While healers

  18. Tectonic evolution and oil and gas of Tarim basin

    NASA Astrophysics Data System (ADS)

    Yuzhu, Kang; Zhihong, Kang

    According to the new results achieved in the past ten years and more, using mobilism and the theory of polycycle by Huang Jiqing (1977, 1984), the formation of the basement of the Tarim basin and its characteristics are summarized. The prototype basins formed since Sinian times are classified into rift basin, continental marginal basin, cratonic basin, foreland basin and others. The Tarim basin is regarded as a huge oil- and gas-bearing basin superposed by prototype basins of different ages. The tectonic characteristics of these basins including tectonic movements, tectonic migrations, faults and trap types are summarized. In addition, structural control over oil and gas and oil-forming features are analysed.

  19. 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.

  20. Geodynamics of the Sivas Basin (Turkey): from a forearc basin to a retroarc foreland basin

    NASA Astrophysics Data System (ADS)

    Legeay, Etienne; Ringenbach, Jean-Claude; Kergaravat, Charlie; Callot, Jean-Paul; Mohn, Geoffroy; Kavak, Kaan

    2016-04-01

    Anatolia records the consumption of several oceanic basins, from the Northern Neotethys domain, by north-dipping subduction until the end of Mesozoic. The associated obduction event occurred during Campanian, from North to South and from Greece to Oman, leading to the emplacement of ophiolite thrust sheets and associated ophiolitic mélange. In particular, the Sivas Basin in Eastern Anatolia is located at the boundary between the Kırsehir block to the East, Pontide arc to the North and Tauride Platform to the South, sutured by ophiolitic belts. The Sivas Basin formed a Tertiary fold-and-thrust belt, which exhibits mainly north verging thrust in Paleogene deposits, and South verging thrust in oligo-miocene sequence. To understand the northern verging thrust above south verging obduction, it is necessary to zoom out of the basin, and include a set of processes that affect the eastern Anatolia. This study aims to characterize the structural and sedimentary evolution of the Sivas Basin, based on a fieldwork approach, coupled to the interpretation of subsurface data, thermochronology and biostratigraphy. The Sivas Basin was initiated in a forearc setting relatively to the subduction of the Inner-Tauride Ocean while the associated ophiolites are obducted onto the northern passive margin of the Tauride margin. Early Maastrichtian to Paleocene deposits are represented by carbonate platforms located on ophiolitic highs, passing to turbidites and olistostomes toward the North. The early Eocene sediments, mainly composed of ophiolitic clasts, are deposited on a regional unconformity marked along the southern margin of the basin by incisions in response to the emergence of north-verging thrust. The middle Eocene sediments, intensively folded by northward thrusting, are mostly represented by flysch type deposits (olistostromes, mass-flows and turbidites). The onset of the compression is related to the initiation of the Taurus shortening in a retroarc situation, in response to

  1. Hydrocarbon accumulations in the Tarim basin, China

    SciTech Connect

    Li Desheng; Liang Digang; Jia Chengzao; Wang Gang

    1996-10-01

    The Tarim basin is the largest and least explored inland basin in China. The areal extent of the basin reaches 560,000 km{sup 2}. The interior of the basin is mostly covered by the Takla Mekan Desert, which is about 330,000 km{sup 2} in areal extent. The basin has become the object of special attention since China set aside first- and third-round onshore bidding blocks in the Tarim basin for foreign oil firms to explore. The Tarim basin is a polyhistory superimposed basin that has experienced seven evolutionary stages: (1) Sinian-Cambrian-Ordovician aulacogen stage, (2) Silurian-Devonian intracratonic depression stage, (3) Carboniferous marginal sea stage, (4) Permian rift basin stage, (5) Triassic-Jurassic foreland basin stage, (6) Cretaceous-Paleogene NeoTethys bay stage, and (7) Neogene-Pleistocene foreland and inland basin stage. Both the basin`s Paleozoic marine platform sequences and the Mesozoic-Cenozoic terrestrial fills are believed to contain substantial volumes of hydrocarbons. After recent years of exploration, nine oil and gas fields have been proven and 23 discoveries have been made in the Tabei, Tazhong, and Southwest areas. Kekeya, Lunnan, Sangtamu, Jiefangqudong, Donghetang, and Tazhong 4 oil fields have been put into production. Output of crude oil was 2.6 million t (metric tons) (52,000 BOPD) in 1995. The production will increase to 5 million t (100,000 BOPD) in 1997. Giant oil and gas traps probably will be discovered in the Tarim basin. The prospect is promising.

  2. Keuper stratigraphic cycles in the Paris basin and comparison with cycles in other peritethyan basins (German basin and Bresse-Jura basin)

    NASA Astrophysics Data System (ADS)

    Bourquin, Sylvie; Guillocheau, François

    1996-09-01

    High-resolution sequence stratigraphy of the Keuper, Paris Basin, is used to establish correlations between the basin-centre evaporite series and the basin-margin clastics series. The high-resolution correlations show stratigraphic cycle geometries. The Keuper consists of five minor base-level cycles whth occur in the upper portion of the Scythian-Carnian major base-level cycle and the lower part of the Carnian-Liassic major base-level cycle. The maximum relative rate of subsidence for the base-level fall phase of the Scythian-Carnian major cycle occurs in the eastern part of the Paris Basin. During the base-level rise phase of the Carnian-Liassic major cycle, the area of highest rate of subsidence shifted westwards and northwards. This shift records the first occurrence of an independent Paris Basin which was no longer merely the western margin of the German Basin. Two phases of tectonic movement influenced evaporite sedimentation and sequence geometries by creating areas of subsidence where halite could accumulate. The second, within the 'Marnes irisées supérieures', induced a general westward and northward tilt of the basin. Concurrent migration of depocentres to the west and north produced an intra-'Marnes irisées supérieures' truncation. Comparison of the stratigraphic records of the Paris Basin and of other Triassic Peritethyan basins (German Basin, Bresse-Jura Basin and South-East Basin) reveals numerous similarities. The coastal onlap curve of the German Keuper (Aigner and Bachmann, 1992) exhibits many similarities with the sequence evolution of the Paris Basin. But the Triassic succession is more complete in the German Basin and more cycles are observed. The major difference between these two basins during the Keuper is that the 'Marnes irisées inférieures' minor base-level cycle does not occur in the German Basin. In the Bresse-Jura Basin, the major difference concerns the Lettenkohle. One minor base-level cycle is recorded in the Paris Basin while

  3. Formation of lunar basin rings

    USGS Publications Warehouse

    Hodges, C.A.; Wilhelms, D.E.

    1978-01-01

    The origin of the multiple concentric rings that characterize lunar impact basins, and the probable depth and diameter of the transient crater have been widely debated. As an alternative to prevailing "megaterrace" hypotheses, we propose that the outer scarps or mountain rings that delineate the topographic rims of basins-the Cordilleran at Orientale, the Apennine at Imbrium, and the Altai at Nectaris-define the transient cavities, enlarged relatively little by slumping, and thus are analogous to the rim crests of craters like Copernicus; inner rings are uplifted rims of craters nested within the transient cavity. The magnitude of slumping that occurs on all scarps is insufficient to produce major inner rings from the outer. These conclusions are based largely on the observed gradational sequence in lunar central uplifts:. from simple peaks through somewhat annular clusters of peaks, peak and ring combinations and double ring basins, culminating in multiring structures that may also include peaks. In contrast, belts of slump terraces are not gradational with inner rings. Terrestrial analogs suggest two possible mechanisms for producing rings. In some cases, peaks may expand into rings as material is ejected from their cores, as apparently occurred at Gosses Bluff, Australia. A second process, differential excavation of lithologically diverse layers, has produced nested experimental craters and is, we suspect, instrumental in the formation of terrestrial ringed impact craters. Peak expansion could produce double-ring structures in homogeneous materials, but differential excavation is probably required to produce multiring and peak-in-ring configurations in large lunar impact structures. Our interpretation of the representative lunar multiring basin Orientale is consistent with formation of three rings in three layers detected seismically in part of the Moon-the Cordillera (basin-bounding) ring in the upper crust, the composite Montes Rook ring in the underlying

  4. THE ADVANCED CHEMISTRY BASINS PROJECT

    SciTech Connect

    William Goddard; Peter Meulbroek; Yongchun Tang; Lawrence Cathles III

    2004-04-05

    In the next decades, oil exploration by majors and independents will increasingly be in remote, inaccessible areas, or in areas where there has been extensive shallow exploration but deeper exploration potential may remain; areas where the collection of data is expensive, difficult, or even impossible, and where the most efficient use of existing data can drive the economics of the target. The ability to read hydrocarbon chemistry in terms of subsurface migration processes by relating it to the evolution of the basin and fluid migration is perhaps the single technological capability that could most improve our ability to explore effectively because it would allow us to use a vast store of existing or easily collected chemical data to determine the major migration pathways in a basin and to determine if there is deep exploration potential. To this end a the DOE funded a joint effort between California Institute of Technology, Cornell University, and GeoGroup Inc. to assemble a representative set of maturity and maturation kinetic models and develop an advanced basin model able to predict the chemistry of hydrocarbons in a basin from this input data. The four year project is now completed and has produced set of public domain maturity indicator and maturation kinetic data set, an oil chemistry and flash calculation tool operable under Excel, and a user friendly, graphically intuitive basin model that uses this data and flash tool, operates on a PC, and simulates hydrocarbon generation and migration and the chemical changes that can occur during migration (such as phase separation and gas washing). The DOE Advanced Chemistry Basin Model includes a number of new methods that represent advances over current technology. The model is built around the concept of handling arbitrarily detailed chemical composition of fluids in a robust finite-element 2-D grid. There are three themes on which the model focuses: chemical kinetic and equilibrium reaction parameters, chemical

  5. Monitoring the fall of large atmospheric ice conglomerations: a multianalytical approach to the study of the Mejorada del Campo megacryometeor.

    PubMed

    Orellana, Francisco Alamilla; Alegre, José Ma Ramiro; Cordero Pérez, José Carlos; Martín Redondo, Ma Paz; Delgado Huertas, Antonio; Fernández Sampedro, Ma Teresa; Menor-Salván, César; Ruiz-Bermejo, Marta; López-Vera, Fernando; Rodríguez-Losada, José A; Martinez-Frias, Jesus

    2008-04-01

    Certain local atmospheric anomalies, such as the formation of unusually large ice conglomerations (megacryometeors), have been proposed to be a potential natural hazard for people and aviation, as well as geoindicators for fingerprinting larger-scale atmospheric environmental changes. On March 13th 2007, at approximately 10:15 am, an ice chunk weighing about 10 kg fell from the clear-sky and crashed through the roof (around 15 m) of an industrial storage house in Mejorada del Campo, a town located 20 km east from Madrid. The megacryometeor monitoring follow-up and the original investigation presented here includes, for the first time, both logistic and scientific collaboration between the Laboratory of the Environment, Criminalistic Service (SECRIM, the Spanish "Guardia Civil") and academic and scientific institutions (universities and the Spanish National Research Council). We propose that the management procedure of the incident, along with the detailed scientific research and combination of analytical methodologies in different laboratories, can serve as a protocol model for other similar events.

  6. Occurrence of Mycoplasma haemocanis in dogs infested by ticks in Campo Grande, Mato Grosso do Sul, Brazil.

    PubMed

    Soares, Rodrigo Leite; Echeverria, Jessica Teles; Pazzuti, Giovana; Cleveland, Herbert Patric Kellerman; Babo-Terra, Verônica Jorge; Friozi, Elisabete; Ramos, Carlos Alberto do Nascimento

    2016-01-01

    Hemotropic mycoplasmas in dogs, such as Mycoplasma haemocanis, have been described worldwide. Recently, these pathogens have been reported to be causative agent of zoonosis. It is known that its transmission may occur through the action of blood-sucking arthropods (e.g. ticks or fleas), through blood transfusion, contaminated fomites and/or transplacentally. In Brazil, M. haemocanis is present in practically all regions and the tick Rhipicephalus sanguineus sensu lato is suspected the main vector. In the municipality of Campo Grande, state of Mato Grosso do Sul, there is little information about infection of dogs by M. haemocanis, or on the main epidemiological features associated with it. Thus, the aim of the present study was to determine the occurrence of M. haemocanis among dogs infested by ticks and to assess possible associations with some epidemiological factors. The polymerase chain reaction (PCR) and DNA sequencing were used to analyze dog blood samples (n = 94). DNA from M. haemocanis was detected in four samples. No significant associations were observed with any epidemiological parameter analyzed here. However, the results from this study confirm that this pathogen is circulating in this region and should be considered in the differential diagnosis of diseases among anemic dogs.

  7. The age of the Tunas formation in the Sauce Grande basin-Ventana foldbelt (Argentina): Implications for the Permian evolution of the southwestern margin of Gondwana

    NASA Astrophysics Data System (ADS)

    López-Gamundí, Oscar; Fildani, Andrea; Weislogel, Amy; Rossello, Eduardo

    2013-08-01

    New SHRIMP radiogenic isotope dating on zircons in tuffs (280.8 ± 1.9 Ma) confirms the Early Permian (Artinskian) age of the uppermost section of the Tunas Formation. Tuff-rich levels in the Tunas Formation are exposed in the Ventana foldbelt of central Argentina; they are part of a deltaic to fluvial section corresponding to the late overfilled stage of the Late Paleozoic Sauce Grande foreland basin. Recent SHRIMP dating of zircons from the basal Choiyoi volcanics exposed in western Argentina yielded an age of 281.4 ± 2.5 Ma (Rocha-Campos et al., 2011). The new data for the Tunas tuffs suggest that the volcanism present in the Sauce Grande basin can be considered as the distal equivalent of the earliest episodes of the Choiyoi volcanism of western Argentina. From the palaeoclimatic viewpoint the new Tunas SHRIMP age confirms that by early Artinskian glacial conditions ceased in the Sauce Grande basin and, probably, in adajacent basins in western Gondwana.

  8. Evaluation of Infiltration Basin Performance in Florida

    NASA Astrophysics Data System (ADS)

    Bean, E.

    2012-12-01

    Infiltration basins are commonly utilized to reduce or eliminate urban runoff in Florida. For permitting purposes, basins are required to recover their design volume, runoff from a one inch rainfall event, within 72 hours to satisfy the design criteria and are not required to account for groundwater mounding if volume recovery can be accomplished by filling of soil porosity by vertical infiltration below the basin surface. Forty infiltration basins were included in a field study to determine whether basin hydraulic performance was significantly different from their designed performance. Basins ranged in age from less than one year to over twenty years and land uses were equally divided between Florida Department of Transportation (FDOT) and residential developments. Six test sites within each basin were typically selected to measure infiltration rates using a double ring infiltrometer (DRI), a common method for infiltration basin sizing. Measured rates were statistically compared to designed infiltration rates, taking into account factors of safety. In addition, a surface soil boring was collected from each of the test sites for a series of analyses, including soil texture, bulk density, and organic matter content. Eleven of the 40 evaluated basins were monitored between March 2008 and January 2012 to evaluate whether basins recovered their volumes from one inch events within 72 hours and to evaluate the effectiveness of using DRI rates to evaluate basin performance. Based on DRI rates, 16 (40%) basins had rates less than their designed rates, 10 (25%) had rates equal to their designed rates, and 14 (35%) basins had rates greater than their designed rates. Additionally, basins with coarser soils were also more likely to have DRI rates greater than designs and FDOT basins were more likely than residential basins to have infiltration rates at or above their designed rates. Five of the eleven monitored basins were expected to function as designed by recovering their

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    We analyse the relative importance of the major crustal-scale fault zones and crustal architecture in controlling basin formation, deformation and the structural connections between basins. The North and South Permian Basins of Central Europe are usually defined by the extend of Rotliegend sedimentary and volcanic units and not by a common tectonic origin or development. Instead, the sub-basins that together form the Permian Basins are each controlled by different structural and/or rheological controls that are inherited from Early Paleozoïc and older geodynamic processes, they are even located in different crustal/lithospheric domains. The North Permian basin is located on Baltic crust that was thinned during Late Proterozoïc - Early Paleozoïc times. South of the Thor suture, the South Permian basin and its sub-basins are located on Avalonian crust (Southern North Sea and North German Basins) and on the transition of East European cratonic and Avalonian crust (Polish Through). The size of crustal domains and of the faults that govern basin formation requires a regional-scale to assess their impact on basins and sub-basins. In the case of the Permian Basins this encompasses East Avalonia and surroundings, roughly speaking the area north of the Variscan Rheïc suture, east of the Atlantic and southwest of the Teisseyre-Tornquist line. This approach sheds light on the effects of long lived differences in crustal fabric which are responsible for spatial heterogeneity in stress and strain magnitudes and zonations of fracturing, burial history and temperature history. The focus on understanding the geomechanical control of large crustal-scale fault structures will provide the constraints and geometrical and compositional input for local models of stress and strain. Considering their fundamentally different structural and rheological controls, the Permian (sub)basins have a remarkably common history of subsidence and inversion, suggesting a more or less continuous

  10. CLEAR LAKE BASIN 2000 PROJECT

    SciTech Connect

    LAKE COUNTY SANITATION DISTRICT

    2003-03-31

    The following is a final report for the Clear Lake Basin 2000 project. All of the major project construction work was complete and this phase generally included final details and testing. Most of the work was electrical. Erosion control activities were underway to prepare for the rainy season. System testing including pump stations, electrical and computer control systems was conducted. Most of the project focus from November onward was completing punch list items.

  11. Environmental change in the Mississippi River Basin

    NASA Astrophysics Data System (ADS)

    Xu, X.; Wynn, G.; Hassan, M. A.; Donner, S. D.; Sivapalan, M.

    2010-12-01

    Land use, land cover change and hydrological modification are important factors affecting discharge, sediment yield, nutrient flows and precipitation at small and large scales. This presentation analyses the changes in crop and pasture land as well as dam and reservoir construction from 1900 to the present in the Mississippi River Basin (including six main sub-basins), to assess their influence on sediment and nutrient dynamics in the basin. Total cropland and pastureland from 1900-2007 are characterized at 0.5 degree x 0.5 degree spatial resolution from existing satellite-derived datasets. From 1900s to 2000s, total cropland in the Ohio River Basin and the Tennessee River Basin in the east exhibited a decreasing trend. The other sub-basins and the basin as a whole exhibited an increasing trend. The area under pasture in the Ohio, the Tennessee and the Upper Mississippi river basins decreased; it increased in the other sub-basins. The areas of corn, wheat and soybean, the three dominant crops in the United States, from 1950 to 2000 are characterized at 5’ x 5’ spatial resolution from existing inventory and satellite-data. The fractional coverage of soybean and wheat increased in most sub-basins, whereas the fraction of corn remained constant or decreased in most sub-basins. The distribution of dams and large dams (those with a normal storage capacity of 5000 acre-feet or more) built in each decade was generated from the data published by National Atlas of the United States. The analysis showed that the majority of the dams in Mississippi River Basin were built in 1960s and 1970s, but the majority of the large dams were built before the 1950s. These spatial and temporal changes in land use, land cover and hydrological modifications are linked to sediment, nutrient and environmental change of the basin.

  12. Late Cenozoic Basins of northern California

    NASA Astrophysics Data System (ADS)

    Nilsen, Tor H.; Clarke, Samuel H.

    1989-12-01

    The late Cenozoic basins of northern California developed in response to both convergent tectonics associated with subduction of the Farallon plate (and its modern representatives, the Juan de Fuca and Gorda plates) and transform tectonics associated with northward migration of the Mendocino triple junction and formation of the San Andreas fault system. The modern Eel River basin north of the Mendocino triple junction is an active forearc basin located between the Cascade magmatic arc to the east and the trench at the foot of the continental slope of northern California and Oregon to the west. Five different types of late Cenozoic basins or fragments of basins are preserved in onshore northern California south of the Mendocino triple junction: (1) remnants of a formerly more extensive Neogene forearc basin preserved locally in downdropped blocks within the San Andreas fault system; (2) remnants of slightly older trench-slope basins that generally developed west of but which may locally structurally underlie the younger forearc basin; (3) younger strike-slip-related structural basins that have developed along active right-lateral faults of the San Andreas fault system; (4) broad shallow embayments, perhaps similar to the modern San Francisco Bay, that were connected to the deeper Pacific Ocean to the west; and (5) structurally emplaced remnants of oceanic crust and its overlying sedimentary cover (the King Range terrane). Our preliminary stratigraphic and sedimentologic studies suggest that much of northern California was covered during the Neogene by a forearc basin that may have extended as far south as the San Francisco Bay region and into the southern San Joaquin Valley. As the Mendocino triple junction migrated northward during the late Cenozoic, the southern margin of the forearc basin was uplifted, basin deposits were stripped off by erosion, and the locus of forearc sedimentation shifted progressively northward through time. Preserved but isolated fragments

  13. Geology of interior cratonic sag basins

    SciTech Connect

    Leighton, M.W.; Eidel, J.J.; Kolata, D.R.; Oltz, D.F. )

    1990-05-01

    Interior cratonic sag basins are thick accumulations of sediment, generally more or less oval in shape, located entirely in the interiors of continental masses. Some are single-cycle basins and others are characterized by repeated sag cycles or are complex polyhistory basins. Many appear to have developed over ancient rift systems. Interior cratonic sag basins are typified by a dominance of flexural over fault-controlled subsidence, and a low ratio of sediment volume to surface area of the basin. The Baltic, Carpentaria, Illinois, Michigan, Parana, Paris, and Williston basins are examples of interior cratonic sag basins. Tectonics played a dominant role in controlling the shapes and the geometries of the juxtaposed packets of sedimentary sequences. While the mechanics of tectonic control are not clear, evidence suggests that the movements are apparently related to convergence of lithospheric plates and collision and breakup of continents. Whatever the cause, tectonic movements controlled the freeboard of continents, altering base level and initiating new tectono-sedimentologic regimes. Sag basins situated in low latitudes during their development commonly were sites of thick carbonates (e.g., Illinois, Michigan, Williston, and Paris basins). In contrast, siliciclastic sedimentation characterized basins that formed in higher latitudes (e.g., Parana and Carpentaria basins). Highly productive sag basins are characterized by widespread, mature, organic-rich source rocks, large structures, and good seals. Nonproductive basins have one or more of the following characteristics: immature source rocks, leaky plumbing, freshwater flushing, and/or complex geology due to numerous intrusions that inhibit mapping of plays.

  14. Basin stability in delayed dynamics

    PubMed Central

    Leng, Siyang; Lin, Wei; Kurths, Jürgen

    2016-01-01

    Basin stability (BS) is a universal concept for complex systems studies, which focuses on the volume of the basin of attraction instead of the traditional linearization-based approach. It has a lot of applications in real-world systems especially in dynamical systems with a phenomenon of multi-stability, which is even more ubiquitous in delayed dynamics such as the firing neurons, the climatological processes, and the power grids. Due to the infinite dimensional property of the space for the initial values, how to properly define the basin’s volume for delayed dynamics remains a fundamental problem. We propose here a technique which projects the infinite dimensional initial state space to a finite-dimensional Euclidean space by expanding the initial function along with different orthogonal or nonorthogonal basis. A generalized concept of basin’s volume in delayed dynamics and a highly practicable calculating algorithm with a cross-validation procedure are provided to numerically estimate the basin of attraction in delayed dynamics. We show potential applicabilities of this approach by applying it to study several representative systems of biological or/and physical significance, including the delayed Hopfield neuronal model with multistability and delayed complex networks with synchronization dynamics. PMID:26907568

  15. K West Basin canister survey

    SciTech Connect

    Pitner, A.L.

    1998-08-26

    A survey was conducted of the K West Basin to determine the distribution of canister types that contain the irradiated N Reactor fuel. An underwater camera was used to conduct the survey during June 1998, and the results were recorded on videotape. A full row-by-row survey of the entire basin was performed, with the distinction between aluminum and stainless steel Mark 1 canisters made by the presence or absence of steel rings on the canister trunions (aluminum canisters have the steel rings). The results of the survey are presented in tables and figures. Grid maps of the three bays show the canister lid ID number and the canister type in each location that contained fuel. The following abbreviations are used in the grid maps for canister type designation: IA = Mark 1 aluminum, IS = Mark 1 stainless steel, and 2 = Mark 2 stainless steel. An overall summary of the canister distribution survey is presented in Table 1. The total number of canisters found to contain fuel was 3842, with 20% being Mark 1 Al, 25% being Mark 1 SS, and 55% being Mark 2 SS. The aluminum canisters were predominantly located in the East and West bays of the basin.

  16. Great Basin geoscience data base

    USGS Publications Warehouse

    Raines, Gary L.; Sawatzky, Don L.; Connors, Katherine A.

    1996-01-01

    This CD-ROM serves as the archive for 73 digital GIS data set for the Great Basin. The data sets cover Nevada, eastern California, southeastern Oregon, southern Idaho, and western Utah. Some of the data sets are incomplete for the total area. On the CD-ROM, the data are provided in three formats, a prototype Federal Data Exchange standard format, the ESRI PC ARCVIEW1 format for viewing the data, and the ESRI ARC/INFO export format. Extensive documentation is provided to describe the data, the sources, and data enhancements. The following data are provided. One group of coverages comes primarily from 1:2,000,000-scale National Atlas data and can be assembled for use as base maps. These various forms of topographic information. In addition, public land system data sets are provided from the 1:2,500,000-scale Geologic Map of the United States and 1:500,000-scale geologic maps of Nevada, Oregon, and Utah. Geochemical data from the National Uranium Resource Evaluation (NURE) program are provided for most of the Great Basin. Geophysical data are provided for most of the Great Basin, typically gridded data with a spacing of 1 km. The geophysical data sets include aeromagnetics, gravity, radiometric data, and several derivative products. The thematic data sets include geochronology, calderas, pluvial lakes, tectonic extension domains, distribution of pre-Cenozoic terranes, limonite anomalies, Landsat linear features, mineral sites, and Bureau of Land Management exploration and mining permits.

  17. Basin stability in delayed dynamics

    NASA Astrophysics Data System (ADS)

    Leng, Siyang; Lin, Wei; Kurths, Jürgen

    2016-02-01

    Basin stability (BS) is a universal concept for complex systems studies, which focuses on the volume of the basin of attraction instead of the traditional linearization-based approach. It has a lot of applications in real-world systems especially in dynamical systems with a phenomenon of multi-stability, which is even more ubiquitous in delayed dynamics such as the firing neurons, the climatological processes, and the power grids. Due to the infinite dimensional property of the space for the initial values, how to properly define the basin’s volume for delayed dynamics remains a fundamental problem. We propose here a technique which projects the infinite dimensional initial state space to a finite-dimensional Euclidean space by expanding the initial function along with different orthogonal or nonorthogonal basis. A generalized concept of basin’s volume in delayed dynamics and a highly practicable calculating algorithm with a cross-validation procedure are provided to numerically estimate the basin of attraction in delayed dynamics. We show potential applicabilities of this approach by applying it to study several representative systems of biological or/and physical significance, including the delayed Hopfield neuronal model with multistability and delayed complex networks with synchronization dynamics.

  18. Biogeochemistry of a Suburban Basin

    NASA Astrophysics Data System (ADS)

    McDowell, W. H.; Daley, M. L.; Blumberg, J.

    2002-12-01

    A long-term research effort was recently established in the Lamprey River basin in southeastern New Hampshire. The watershed is largely forested, and has significant amounts of wetlands due to the relatively low topographic relief. Human population growth is rapid, resulting in conversion of forest and agricultural land to housing tracts. The primary focus of the project will be to examine the relationships between land use, land cover and water quality as the watershed continues to increase in population density. A secondary emphasis will be to examine the interactions between hydrologic flow paths, climatic variability, and biogeochemical processes that drive groundwater and surface water quality in the basin. Our initial work has quantified landscape attributes and related them to water quality. Results to date show that small tributary streams are relatively high in nitrogen relative to the main stem of the Lamprey; that human population density drives nitrate concentrations in the basin; and that DOC flux is predicted well by the model of Aitkenhead and McDowell that links DOC flux to watershed C:N ratio.

  19. The geologic history of Margaritifer basin, Mars

    USGS Publications Warehouse

    Salvatore, M. R.; Kraft, M. D.; Edwards, Christopher; Christensen, P.R.

    2016-01-01

    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava (ULM) outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre Basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  20. The geologic history of Margaritifer basin, Mars

    NASA Astrophysics Data System (ADS)

    Salvatore, M. R.; Kraft, M. D.; Edwards, C. S.; Christensen, P. R.

    2016-03-01

    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  1. Gravity Anomalies of the Lunar Orientale Basin and the Mercurian Caloris Basin

    NASA Astrophysics Data System (ADS)

    Blair, D. M.; Johnson, B. C.; Freed, A. M.; Melosh, H. J.

    2013-08-01

    We model the formation and evolution of the lunar Orientale and mercurian Caloris basin gravity anomalies using a combination of hydrocode and finite-element methods, constrained by free-air and Bouguer gravity anomalies and basin topography.

  2. Thermal evolution of sedimentary basins in Alaska

    USGS Publications Warehouse

    Johnsson, Mark J.; Howell, D.G.

    1996-01-01

    The complex tectonic collage of Alaska is reflected in the conjunction of rocks of widely varying thermal maturity. Indicators of the level of thermal maturity of rocks exposed at the surface, such as vitrinite reflectance and conodont color alteration index, can help constrain the tectonic evolution of such complex regions and, when combined with petrographic, modern heat flow, thermogeochronologic, and isotopic data, allow for the detailed evaluation of a region?s burial and uplift history. We have collected and assembled nearly 10,000 vitrinite-reflectance and conodont-color-alteration index values from the literature, previous U.S. Geological Survey investigations, and our own studies in Alaska. This database allows for the first synthesis of thermal maturity on a broadly regional scale. Post-accretionary sedimentary basins in Alaska show wide variability in terms of thermal maturity. The Tertiary interior basins, as well as some of the forearc and backarc basins associated with the Aleutian Arc, are presently at their greatest depth of burial, with immature rocks exposed at the surface. Other basins, such as some backarc basins on the Alaska Peninsula, show higher thermal maturities, indicating modest uplift, perhaps in conjunction with higher geothermal gradients related to the arc itself. Cretaceous ?flysch? basins, such as the Yukon-Koyukuk basin, are at much higher thermal maturity, reflecting great amounts of uplift perhaps associated with compressional regimes generated through terrane accretion. Many sedimentary basins in Alaska, such as the Yukon-Koyukuk and Colville basins, show higher thermal maturity at basin margins, perhaps reflecting greater uplift of the margins in response to isostatic unloading, owing to erosion of the hinterland adjacent to the basin or to compressional stresses adjacent to basin margins.

  3. Reserve estimates in western basins. Part 2: Piceance Basin

    SciTech Connect

    1995-10-01

    This study characterizes an extremely large gas resource located in low permeability, sandstone reservoirs of the Mesaverde group in the Piceance Basin, Colorado. Total in place resource is estimated at 307.3 Tcf. Via application of geologic, engineering and economic criteria, the portion of this resource potentially recoverable as reserves is estimated. Those volumes estimated include probable, possible and potential categories and total 5.8 Tcf as a mean estimate of recoverable gas for all plays considered in the basin. About 82.6% of the total evaluated resource is contained within sandstones that have extremely poor reservoir properties with permeabilities considered too low for commerciality using current frac technology. Cost reductions and technology improvements will be required to unlock portions of this enormous resource. Approximately 2.7% of the total resource is contained within sandstone reservoirs which do not respond to massive hydraulic fracture treatments, probably due to their natural lenticular nature. Approximately 6.8% of the total resource is located in deeply buried settings below deepest established production. Approximately 7.9% of the total resource is considered to represent tight reservoirs that may be commercially exploited using today`s hydraulic fracturing technology. Recent technology advances in hydraulic fracturing practices in the Piceance Basin Mesaverde has resulted in a marked improvement in per well gas recovery which, where demonstrated, has been incorporated into the estimates provided in this report. This improvement is so significant in changing the risk-reward relationship that has historically characterized this play, that previously uneconomic areas and resources will graduate to the economically exploitable category. 48 refs., 96 figs., 18 tabs.

  4. Reserves in western basins: Part 1, Greater Green River basin

    SciTech Connect

    Not Available

    1993-10-01

    This study characterizes an extremely large gas resource located in low permeability, overpressured sandstone reservoirs located below 8,000 feet drill depth in the Greater Green River basin, Wyoming. Total in place resource is estimated at 1,968 Tcf. Via application of geologic, engineering and economic criteria, the portion of this resource potentially recoverable as reserves is estimated. Those volumes estimated include probable, possible and potential categories and total 33 Tcf as a mean estimate of recoverable gas for all plays considered in the basin. Five plays (formations) were included in this study and each was separately analyzed in terms of its overpressured, tight gas resource, established productive characteristics and future reserves potential based on a constant $2/Mcf wellhead gas price scenario. A scheme has been developed to break the overall resource estimate down into components that can be considered as differing technical and economic challenges that must be overcome in order to exploit such resources: in other words, to convert those resources to economically recoverable reserves. Total recoverable reserves estimates of 33 Tcf do not include the existing production from overpressured tight reservoirs in the basin. These have estimated ultimate recovery of approximately 1.6 Tcf, or a per well average recovery of 2.3 Bcf. Due to the fact that considerable pay thicknesses can be present, wells can be economic despite limited drainage areas. It is typical for significant bypassed gas to be present at inter-well locations because drainage areas are commonly less than regulatory well spacing requirements.

  5. Evapotranspiration estimation in pastures at the municipality of Campo Grande, Brazil, using SEBAL and remote sensing data

    NASA Astrophysics Data System (ADS)

    Andrade, R. G.; Leivas, J. F.; Alvarez, I. A.; Vicente, L. E.; Nogueira, S. F.; Hott, M. C.; Takemura, C. M.; Gomes, D.

    2011-12-01

    The knowledge of the total water loss by evapotranspiration is essential for plant growth and development assessments. Studies show that the success of the Brazilian livestock is directly linked to the fact that bovine cattle is reared in pastures, which enables low cost beef production. However, many factors influence the productive capacity of pastures and, consequently, beef production. Among these, there are variations in precipitation, causing periods of water deficit even during rainy seasons, which makes evapotranspiration a major factor in the diagnosis of climatic and environmental conditions of pasture areas. Remote sensing information has been used by several models and algorithms for obtaining parameters of the Earth's surface. The Surface Energy Balance Algorithms for Land (SEBAL) is an algorithm for evapotranspiration estimation for large areas. It is processed by means of computational steps, which predict a full assessment of the solar radiation and energy on the Earth's surface. For that it uses data of sensors that collect wavelengths in the visible, reflective infrared and thermal bands. This study aimed at estimating actual daily evapotranspiration (ETdaily) in pasture areas at Embrapa Beef Cattle's Experimental Farm, located in the municipality of Campo Grande, Brazil, by means of the SEBAL algorithm and Landsat 5-TM images. For the scenes of May 9, June 28, July 7 and October 2, 2009, the ETdaily varied from 0.50 to 3.50 mm/day with an average of 1.85 mm/day for pasture areas. The application of the SEBAL algorithm proved itself adequate in extensive areas, and it is possible to use it for monitoring pasture conditions, thus contributing to making decisions that favor beef cattle production with environmental sustainability.

  6. Evapotranspiration estimation in pastures at the municipality of Campo Grande, Brazil, using SEBAL and remote sensing data

    NASA Astrophysics Data System (ADS)

    Andrade, R. G.; Leivas, J. F.; Hott, M. C.; Alvarez, I. A.; Vicente, L. E.; Nogueira, S. F.; Takemura, C. M.

    2011-12-01

    The knowledge of the total water loss by evapotranspiration is essential for plant growth and development assessments. Studies show that the success of the Brazilian livestock is directly linked to the fact that bovine cattle is reared in pastures, which enables low cost beef production. However, many factors influence the productive capacity of pastures and, consequently, beef production. Among these, there are variations in precipitation, causing periods of water deficit even during rainy seasons, which makes evapotranspiration a major factor in the diagnosis of climatic and environmental conditions of pasture areas. Remote sensing information has been used by several models and algorithms for obtaining parameters of the Earth's surface. The Surface Energy Balance Algorithms for Land (SEBAL) is an algorithm for evapotranspiration estimation for large areas. It is processed by means of computational steps, which predict a full assessment of the solar radiation and energy on the Earth's surface. For that it uses data of sensors that collect wavelengths in the visible, reflective infrared and thermal bands. This study aimed at estimating actual daily evapotranspiration (ETdaily) in pasture areas at Embrapa Beef Cattle's Experimental Farm, located in the municipality of Campo Grande, Brazil, by means of the SEBAL algorithm and Landsat 5-TM images. For the scenes of May 9, June 28, July 7 and October 2, 2009, the ETdaily varied from 0.50 to 3.50 mm d-1 with an average of 1.85 mm d-1 for pasture areas. The application of the SEBAL algorithm proved itself adequate in extensive areas, and it is possible to use it for monitoring pasture conditions, thus contributing to making decisions that favor beef cattle production with environmental sustainability.

  7. Petroleum system of the Gippsland Basin, Australia

    USGS Publications Warehouse

    Bishop, Michele G.

    2000-01-01

    The Gippsland Basin Province 3930, located on the southeastern coast of Australia, is formed from two successive failed rifts that developed into a passive margin during the Cretaceous. Formation of this basin is related to the break up of Gondwana, which resulted in the separation of Antarctica from Australia, and the separation of the New Zealand and Lord Howe Rise continental crust from Australia. Coals and coaly shales of Late Cretaceous through Eocene age are the source rocks for oil and gas that accumulated predominantly in anticlinal traps. The basin was Australia?s major producing basin until 1996 when daily oil/condensate production from the North West Shelf surpassed it.

  8. Late Paleozoic structural evolution of Permian basin

    SciTech Connect

    Ewing, T.E.

    1984-04-01

    The southern Permian basin is underlain by the NNW-trending Central Basin disturbed belt of Wolfcamp age (Lower Permian), the deep Delaware basin to its west, and the shallower Midland basin to its eat. The disturbed belt is highly segmented with zones of left-lateral offset. Major segments from south to north are: the Puckett-Grey Ranch zone; the Fort Stockton uplift; the Monahans transverse zone; the Andector ridges and the Eunice ridge; the Hobbs transverse zone; and the Tatum ridges, which abut the broad Roosevelt uplift to the north. The disturbed belt may have originated along rift zones of either Precambrian or Cambrian age. The extent of Lower and Middle Pennsylvanian deformation is unclear; much of the Val Verde basin-Ozona arch structure may have formed then. The main Wolfcamp deformation over thrust the West Texas crustal block against the Delaware block, with local denudation of the uplifted edge and eastward-directed backthrusting into the Midland basin. Latter in the Permian, the area was the center of a subcontinental bowl of subsidence - the Permian basin proper. The disturbed belt formed a pedestal for the carbonate accumulations which created the Central Basin platform. The major pre-Permian reservoirs of the Permian basin lie in large structural and unconformity-bounded traps on uplift ridges and domes. Further work on the regional structural style may help to predict fracture trends, to assess the timing of oil migration, and to evaluate intrareservoir variations in the overlying Permian giant oil fields.

  9. Petroleum geology of Norton basin, Alaska

    SciTech Connect

    Fisher, M.A.

    1982-03-01

    Basement rocks beneath the main part of the Norton basin were deformed and heated during the Late Jurassic and Early Cretaceous to the extent that these rocks were not capable of generating hydrocarbons when the basin formed during the latest Cretaceous or early Paleogene. Consequently, source rocks for oil, if they exist, are most likely to be within the basin fill. If the Norton basin began to form 65 m.y. ago, subsided at a nearly constant rate, and had an average geothermal gradient of between 35 and 45/sup 0/C/km, then rocks as young as late Oligocene are in the oil window (vitrinite reflectance between 0.65 and 1.30%). The appearance on seismic sections of reflections from rocks in and below the calculated oil window suggests that these rocks were deposited in a nonmarine environment. Thus, gas and condensate are the most likely hydrocarbons to be present in the basin. Because of their shallow depth of burial, Neogene (possibly marine) rocks are not likely to be thermally mature anywhere in the basin. Deep parts of the basin formed as isolated faultbounded lows; consequently, the volume of mature rocks makes up at most 11% of the total basin fill. Numerous potential traps for hydrocarbons exist in the Norton basin; the traps include fractured or weathered basement rocks in horsts, strata in alluvial fans on the flanks of horsts, and arched strata over horsts.

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  11. Regional geophysics and the basement of cratonic basins: a comparative study with the Michigan basin

    SciTech Connect

    Hinze, W.J.; Lidiak, E.G.

    1986-08-01

    The basement of the Michigan basin consists of four major provinces - the complex metasedimentary, metavolcanic, and igneous rocks of the Penokean orogenic assemblage in the north, the felsic anorogenic igneous rocks to the south, the highly metamorphosed schists, gneisses, and related igneous intrusions of the Grenville province in the east, and a middle Proterozoic rift zone, which transects the basin from the north to the southeast margin. Sparse basement drill holes and characteristic geophysical patterns support this interpretation. The direct geologic information on the basement of other cratonic basins is not as well known. However, regional geophysical surveys and sparse, poorly distributed basement drill holes provide information on the complex character and structural relationships of the basement of other basins. Like the Michigan basin, many cratonic basins (e.g., Illinois, Williston, and Paris basins) are underlain by dense and commonly more magnetic rocks than adjacent areas. As in the Michigan basin, these rocks are interpreted to have a profound effect on the origin and tectonic development of the basins. Geologic and geophysical evidence indicates that many of these dense basement rocks originated in rifts that formed hundreds of millions of years prior to basin development. A comparison of the basement in cratonic basins provides important constraints on the origin and tectonic development of the Michigan basin.

  12. 75 FR 43915 - Basin Electric Power Cooperative: Deer Creek Station

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-27

    ... Rural Utilities Service Basin Electric Power Cooperative: Deer Creek Station AGENCY: Rural Utilities... CFR Part 1794), and the Western Area Power Administration's (Western) NEPA implementing regulations... environmental impacts of and alternatives to Basin Electric Power Cooperative's (Basin Electric) application...

  13. Free energy basin-hopping

    NASA Astrophysics Data System (ADS)

    Sutherland-Cash, K. H.; Wales, D. J.; Chakrabarti, D.

    2015-04-01

    A global optimisation scheme is presented using basin-hopping with the acceptance criterion based on approximate free energy for the corresponding local minima of the potential energy. The method is illustrated for atomic and colloidal clusters and peptides to examine how the predicted global free energy minimum changes with temperature. Using estimates for the local free energies based on harmonic vibrational densities of states provides a computationally effective framework for predicting trends in structure at finite temperature. The resulting scheme represents a powerful tool for exploration of energy landscapes throughout molecular science.

  14. Central Nebraska river basins Nebraska

    USGS Publications Warehouse

    Huntzinger, Thomas L.; Ellis, Michael J.

    1993-01-01

    The Central Nebraska Basins (NAWQA) study unit includes the Platte River and two major tributaries, the Loup and Elkhorn Rivers. Platte River flows are variable of diversions, but the Loup and Elkhorn Rivers originate in an area of dune sand covered by grassland that generates consistent base flows. Ground water has no regional confining units and the system is a water table aquifer throughout. Macroinvertebrate and fish taxa were related to stream flow. One of the four wetland complexes includes habitat for threatened and endangered bird species. A water quality assessments will be based on the differences in environmental setting in each of four subunits within the study unit.

  15. 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

  16. Basin-scale relations via conditioning

    USGS Publications Warehouse

    Troutman, B.M.; Karlinger, M.R.; Guertin, D.P.

    1989-01-01

    A rainfall-runoff model is used in conjunction with a probabilistic description of the input to this model to obtain simple regression-like relations for basin runoff in terms of basin and storm characteristics. These relations, similar to those sought in regionalization studies, are computed by evaluating the conditional distribution of model output given basin and storm characteristics. This method of conditioning provides a general way of examining model sensitivity to various components of model input. The resulting relations may be expected to resemble corresponding relations obtained by regionalization using actual runoff to the extent that the rainfall-runoff model and the model input specification are physically realistic. The probabilistic description of model input is an extension of so-called "random-model" of channel networks and involves postulating an ensemble of basins and associated probability distributions that mimic the variability of basin characteristics seen in nature. Application is made to small basins in the State of Wyoming. Parameters of the input variable distribution are estimated using data from Wyoming, and basin-scale relations are estimated both, parametrically and nonparametrically using model-generated runoff from simulated basins. Resulting basin-scale relations involving annual flood quantiles are in reasonable agreement with those presented in a previous regionalization study, but error estimates are smaller than those in the previous study, an artifact of the simplicity of the rainfall-runoff model used in this paper. We also obtain relations for peak of the instantaneous unit hydrograph which agree fairly well with theoretical relations given in the literature. Finally, we explore the issues of sensitivity of basin-scale, relations and error estimates to parameterization of the model input probability distribution and of how this sensitivity is related to making inferences about a particular ungaged basin. ?? 1989 Springer-Verlag.

  17. Cenozoic evolution of San Joaquin basin, California

    SciTech Connect

    Bartow, J.A.

    1988-03-01

    The Neogene San Joaquin basin in the southern part of the 700-km long Great Valley of California is a successor to a late Mesozoic and earliest Tertiary forearc basin. The transition from forearc basin to the more restricted Neogene marine basin occurred principally during the Paleogene as the plate tectonic setting changed from oblique convergence to normal convergence, and finally to the initiation of tangential (transform) movement near the end of the Oligocene. Regional-scale tectonic events that affected the basin include: (1) clockwise rotation of the southernmost Sierra Nevada, and large-scale en echelon folding in the southern Diablo Range, both perhaps related to Late Cretaceous and early Tertiary right slip on the proto-San-Andreas fault; (2) regional uplift of southern California in the Oligocene that resulted from the subduction of the Pacific-Farallon spreading ridge: (3) extensional tectonism in the Basin and Range province, particularly in the Miocene; (4) wrench tectonism adjacent to the San Andreas fault in the Neogene; (5) northeastward emplacement of a wedge of the Franciscan complex at the west side of the Sierran block, with associated deep-seated thrusting in the late Cenozoic; and (6) the accelerated uplift of the Sierra Nevada beginning in the late Miocene. Neogene basin history was controlled principally by the tectonic effects of the northwestward migration of the Mendocino triple junction along the California continental margin and by the subsequent wrench tectonism associated with the San Andreas fault system. East-west compression in the basin, resulting from extension in the Basin and Range province was an important contributing factor to crustal shortening at the west side of the valley. Analysis of the sedimentary history of the basin, which was controlled to some extent by eustatic sea level change, enables reconstruction of the basin paleogeography through the Cenozoic.

  18. Potential for a basin-centered gas accumulation in the Albuquerque Basin, New Mexico

    USGS Publications Warehouse

    Johnson, Ronald C.; Finn, Thomsa M.; Nuccio, Vito F.

    2001-01-01

    The potential that a basin-centered or continuous-type gas accumulation is present in the Albuquerque Basin in central New Mexico was investigated. The Albuquerque Basin is one of the many rift basins that make up the Rio Grand rift system, an area of active extension from Oligocene to recent time. The basin is significantly different from other Rocky Mountain basins that contain basin-centered gas accumulations because it is actively subsiding and is at near maximum burial and heating conditions at the present time. Burial reconstructions suggest that Cretaceous-age source rocks began to generate gas in the deeper parts of the basin about 20 million years ago and are still generating large amounts of gas. The high mud weights typically used while drilling the Cretaceous interval in the deeper areas of the basin suggest some degree of over-pressuring. Gas shows are commonly reported while drilling through the Cretaceous interval; however, attempts to complete gas wells in the Cretaceous have resulted in subeconomic quantities of gas, primarily because of low permeabilities. Little water has been reported. All of these characteristics suggest that a basin-centered gas accumulation of some sort is present in the Albuquerque Basin.

  19. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... 1—Opposite Brossard. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for vessels up to... vessels up to 107 m in overall length. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut...

  20. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... 1—Opposite Brossard. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for vessels up to... vessels up to 107 m in overall length. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut...

  1. 33 CFR 401.48 - Turning basins.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... 1—Opposite Brossard. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut for vessels up to... vessels up to 107 m in overall length. (b) Turning Basin No. 2—Between Lock 7 and the Guard Gate Cut...

  2. African sedimentary basins - Tectonic controls on prospectivity

    SciTech Connect

    Bunter, M.A.G.; Crossley, R.; Hammill, M.; Jones, P.W.; Morgan, R.K.; Needham, D.T.; Spaargaren, F.A. )

    1991-03-01

    An important prerequisite for the evaluation of any sedimentary basin is the understanding of its regional tectonic setting. This is especially so in the underexplored regions of Africa. The majority of African sedimentary basins developed in an extensional setting although some have undergone subsequent compressional or transpressional deformation. The geometry and evolution of these basins is often influenced by basement structure. The extensional phase of basin development controls not only the distribution of syn-rift sediments but also the magnitude of post-rift regional subsidence and the preservation or removal of pre-rift sediments. This has important consequences for exploration models of syn-rift and pre-rift source rocks and reservoirs. Post-rift basin inversion and uplift provide crucial controls on the preservation of mature source rocks and quality of reservoirs. The distribution, nature, timing, and possible mechanisms of this uplift in Africa will be addressed. The hydrocarbon prospectivity of African basis appears to be highly variable although the limited exploration of some regions makes the exact extent of this variability unclear. Basins considered potentially prospective range from late Precambrian to Tertiary in age. The various tectonic controls outlined above, and criteria for the evaluation of underexplored areas, will be demonstrated by reference to basins studied by The Robertson Group. Examples described include basins from Bagon, Angola, Namibia, East Africa, Tertiary Rift and Karoo Rifts, and North Africa (Sudan, Egypt, Algeria, and Morocco).

  3. Frontier sedimentary basins of New Zealand region

    SciTech Connect

    Beggs, J.M. )

    1991-03-01

    Petroleum-prospective basins of New Zealand began to form by mid-Cretaceous rifting of crustal elements previously assembled at the Gondwana continental margin. During the latest Cretaceous-early Cenozoic New Zealand separated from Australia and Antarctica by sea-floor spreading. An overall transgression in widely recorded in this post-rift phase, with decreasing clastic sediment supply as land area and relief were reduced. Mid-Cenozoic initiation of the modern plate boundary has resulted in uplift of mountain ranges, subsidence and filling of troughs, progradation of the shelf, and common reactivation or eversion of older structures. Petroleum potential of less explored basins can be compared to the productive Taranki basin. Source rocks are coal-rich deposits of the rift phase, also developed in Great South, Canterbury/Chatham, Western Southland, West Coast, and Northland basins. A different source contributes to oil and gas seeps on the East Coast, a continental margin during Late Cretaceous. The main reservoirs of Taranaki are early Cenozoic coastal and fluvial sands, also present in Great South, Canterbury, and West Coast and possibly other basins. Other Taranaki reservoirs include mid-Cenozoic limestone and Miocene turbidites, which are widespread in most other basins. Pliocene limestones have excellent reservoir potential on the East Coast. Late Cenozoic tectonics, essential to trap development and significant for maturation in Taranaki, have created similar structures in basins near the plate boundary but are less significant in the development of Great South, eastern Canterbury/Chatham, and Northland basins.

  4. Relation between Tethys sea and Tarim basin

    SciTech Connect

    Wei Junchao )

    1988-08-01

    The Tarim basin is the largest continental basin in China. It is known as the heart of central Asia. Still it was related to the Mediterranean Sea in the geological past. Based on the investigations of paleontology, stratigraphy, tectonics, and remote sensing, it is suggested that Tethys and the Tarim basin should be connected from the Late Cretaceous to Miocene. The northern branch of the Tethys sea channel began to pass through the Alay gap and invade the Tarim basin at the beginning of the Late Cretaceous. Up to the Miocene, marine invasion and marine regression must have happened six times in the western Tarim basin. The Paleocene marine invasion encroached upon the widest area and lasted the longest of the six times, which extended to the region of the southern Hotan River. The occurrence of the Paleocene marine fossils in the Kuqa Seg indicates the influence of the marine invasion. At the end of the Miocene, seawater receded fully from the Tarim basin. A Miocene petroleum field has been found in the Yecheng Seg of the western Tarim basin. According to the relationship between Tethys and the Tarim basin, the potentialities of the Late Cretaceous-Miocene hydrocarbon source are considered to be great.

  5. Water quality in the eastern Iowa basins

    USGS Publications Warehouse

    Kalkhoff, Stephen J.; Barnes, Kymm K.; Becher, Kent D.; Savoca, Mark E.; Schnoebelen, Douglas J.; Sadorf, Eric M.; Porter, Stephen D.; Sullivan, Daniel J.; Creswell, John

    2001-01-01

    The Eastern Iowa Basins Study Unit includes the Wapsipinicon, Cedar, Iowa, and Skunk River basins and covers approximately 19,500 square miles in eastern Iowa and southern Minnesota. More than 90 percent of the land in the study unit is used for agricultural purposes. Forested areas account for only 4 percent of the land area.

  6. Scientific review of great basin wildfire issues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The University Nevada Reno, College of Agriculture and Resource Concepts Inc., co-sponsored a Great Basin Wildfire Forum in September 2007 to address a “Scientific Review of the Ecological and Management History of Great Basin Natural Resources and Recommendations to Achieve Ecosystem Restoration”. ...

  7. Scientific Review of Great Basin Wildfire Issues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The University Nevada Reno, College of Agriculture and Resource Concepts Inc., co-sponsored a Great Basin Wildfire Forum in September 2007 to address a “Scientific Review of the Ecological and Management History of Great Basin Natural Resources and Recommendations to Achieve Ecosystem Restoration”. ...

  8. Wyoming Basin Rapid Ecoregional Assessment

    USGS Publications Warehouse

    Carr, Natasha B.; Means, Robert E.

    2013-01-01

    The overall goal of the Wyoming Basin Rapid Ecoregional Assessment (REA) is to provide information that supports regional planning and analysis for the management of ecological resources. The REA provides an assessment of baseline ecological conditions, an evaluation of current risks from drivers of ecosystem change (including energy development, fire, and invasive species), and a predictive capacity for evaluating future risks (including climate change). Additionally, the REA may be used for identifying priority areas for conservation or restoration and for assessing cumulative effects of multiple land uses. The Wyoming Basin REA will address Management Questions developed by the Bureau of Land Management and other agency partners for 8 major biomes and 19 species or species assemblages. The maps developed for addressing Management Questions will be integrated into overall maps of landscape-level ecological values and risks. The maps can be used to address the goals of the REA at a number of levels: for individual species, species assemblages, aquatic and terrestrial systems, and for the entire ecoregion. This allows flexibility in how the products of the REA are compiled to inform planning and management actions across a broad range of spatial scales.

  9. Basins in ARC-continental collisions

    USGS Publications Warehouse

    Draut, Amy E.; Clift, Peter D.; Busby, Cathy; Azor, Antonio

    2012-01-01

    Arc-continent collisions occur commonly in the plate-tectonic cycle and result in rapidly formed and rapidly collapsing orogens, often spanning just 5-15 My. Growth of continental masses through arc-continent collision is widely thought to be a major process governing the structural and geochemical evolution of the continental crust over geologic time. Collisions of intra-oceanic arcs with passive continental margins (a situation in which the arc, on the upper plate, faces the continent) involve a substantially different geometry than collisions of intra-oceanic arcs with active continental margins (a situation requiring more than one convergence zone and in which the arc, on the lower plate, backs into the continent), with variable preservation potential for basins in each case. Substantial differences also occur between trench and forearc evolution in tectonically erosive versus tectonically accreting margins, both before and after collision. We examine the evolution of trenches, trench-slope basins, forearc basins, intra-arc basins, and backarc basins during arc-continent collision. The preservation potential of trench-slope basins is low; in collision they are rapidly uplifted and eroded, and at erosive margins they are progressively destroyed by subduction erosion. Post-collisional preservation of trench sediment and trench-slope basins is biased toward margins that were tectonically accreting for a substantial length of time before collision. Forearc basins in erosive margins are usually floored by strong lithosphere and may survive collision with a passive margin, sometimes continuing sedimentation throughout collision and orogeny. The low flexural rigidity of intra-arc basins makes them deep and, if preserved, potentially long records of arc and collisional tectonism. Backarc basins, in contrast, are typically subducted and their sediment either lost or preserved only as fragments in melange sequences. A substantial proportion of the sediment derived from

  10. Rifting Thick Lithosphere - Canning Basin, Western Australia

    NASA Astrophysics Data System (ADS)

    Czarnota, Karol; White, Nicky

    2016-04-01

    The subsidence histories and architecture of most, but not all, rift basins are elegantly explained by extension of ~120 km thick lithosphere followed by thermal re-thickening of the lithospheric mantle to its pre-rift thickness. Although this well-established model underpins most basin analysis, it is unclear whether the model explains the subsidence of rift basins developed over substantially thick lithosphere (as imaged by seismic tomography beneath substantial portions of the continents). The Canning Basin of Western Australia is an example where a rift basin putatively overlies lithosphere ≥180 km thick, imaged using shear wave tomography. Subsidence modelling in this study shows that the entire subsidence history of the <300 km wide and <6 km thick western Canning Basin is adequately explained by mild Ordovician extension (β≈1.2) of ~120 km thick lithosphere followed by post-rift thermal subsidence. This is consistent with the established model, described above, albeit with perturbations due to transient dynamic topography support which are expressed as basin-wide unconformities. In contrast the <150 km wide and ~15 km thick Fitzroy Trough of the eastern Canning Basin reveals an almost continuous period of normal faulting between the Ordovician and Carboniferous (β<2.0) followed by negligible post-rift thermal subsidence. These features cannot be readily explained by the established model of rift basin development. We attribute the difference in basin architecture between the western and eastern Canning Basin to rifting of thick lithosphere beneath the eastern part, verified by the presence of ~20 Ma diamond-bearing lamproites intruded into the basin depocentre. In order to account for the observed subsidence, at standard crustal densities, the lithospheric mantle is required to be depleted in density by 50-70 kg m-3, which is in line with estimates derived from modelling rare-earth element concentrations of the ~20 Ma lamproites and global isostatic

  11. Petroleum geochemistry of the Zala Basin, Hungary

    USGS Publications Warehouse

    Clayton, J.L.; Koncz, I.

    1994-01-01

    The Zala basin is a subbasin within the Pannonian basin. Geochemical study of oils and rocks in the basin indicate that two, and possibly three, genetic oil types are present in the basin. Miocene source rocks, previously believed to be the predominant source rock, have expelled minor amounts of hydrocarbons. The main source rock is the Upper Triassic (Rhaetian) Kossen Marl Formation or its stratigraphic equivalent. Knowledge of the geochemical characteristics of oils derived from these Upper Triassic source rocks and understanding of the source rock distribution and maturation history are important for recognizing Triassic oil-source bed relationships and for further exploration in other basins in Hungary and other parts of Europe where Triassic source rocks are present. -from Authors

  12. 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.

  13. Determination of the Relationship between Hydrologic Processes and Basin Morphometry - The Lamos Basin (Mersin, Turkey)

    NASA Astrophysics Data System (ADS)

    Yıldırım, Ümit; Güler, Cüneyt

    2016-04-01

    This study has been carried out to determine the relationship between hydrologic processes and basin morphometry in the Lamos Basin, which is located at the northern part of the Mersin (SE Turkey). The morphometric parameters of the basin was derived from the 1:25K scale topographic map sheets that were digitized using ArcGIS 9.3.1 geographic information system (GIS) software. Morphometric parameters considered in this study include basin area, basin length, basin perimeter length, stream order, stream number, stream length, mean stream length, basin relief, drainage density, stream frequency, drainage texture, bifurcation ratio, form factor, elongation ratio, overland flow length, relief ratio, and hypsometric integral. The results have shown that there are 1252 individual stream reaches with a total length of 1414.1 km in the Lamos basin, which covers an area of 1358 km2 and has a length of 103 km in the N-S direction. Furthermore, the basin has a medium drainage density of 1.04 1/km with a stream frequency and drainage texture values of 0.92 and 4.33, respectively. The basin can be classified as elongated because of the low values of elongation ratio (0.48) and form factor (0.12). The hypsometric integral of the basin (0.58) indicates that it is in the youth period and thus reasonably sensitive to erosion. The values of drainage texture, drainage density, and stream frequency indicate that the Lamos basin is moderately well drained, therefore overland flow in the basin is not expected to be so quick. Thus, in case of occurrence of sudden peak flows, sensitivity to the land sliding and erosion may increase further. As a result, it is suggested that human activities in the basin should be limited in areas in fairly close proximity to the present day stream network to prevent or reduce the risk to life and property.

  14. Preliminary evaluation of nominal drainage basin volume as a potentially useful morphometric parameter for small mountain basins

    SciTech Connect

    Keaton, J.R.

    1985-01-01

    Morphometric basin parameters have been used in quantitative geomorphic assessments since Horton's Hydrophysical Approach in 1945. A relationship between basin form and dominant process in small mountain basins in the western United States would be valuable for use in differentiating basins which produce deep-seated landslides from those which produce debris flows from debris slides. Drainage basin volume seems like it should be a parameter directly related to the dominant process operating in a basin. Consequently, it may be a potentially useful morphometric parameter. Nominal drainage basin volume is herein defined as the volume creates by the basin topography and linear projection of topographic contours across the basin. Incremental volume is computed from area encompassed by topographic contours and projections and the contour interval using the formula for the volume of the frustrum of a cone. Seven basins in the Wasatch Range and five in the Wasatch Plateau of Utah show strong relationship of log Basin Area to log Basin Volume (r/sup 2/ = 0.97). The relationship between average Basin Slope and log Basin Volume was poorer (r/sup 2/ = 0.78) than between Basin Slope and log Basin Area (r/sup 2/ = 0.87). This suggests that basin area may be a more useful parameter than basin volume, especially since area is more easily measured.

  15. Tick-borne agents in domesticated and stray cats from the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil.

    PubMed

    André, Marcos Rogério; Herrera, Heitor Miraglia; Fernandes, Simone de Jesus; de Sousa, Keyla Cartens Marques; Gonçalves, Luiz Ricardo; Domingos, Iara Helena; de Macedo, Gabriel Carvalho; Machado, Rosangela Zacarias

    2015-09-01

    Anaplasmataceae agents, piroplasmids and Hepatozoon spp. have emerged as important pathogens among domestic and wild felines. The present work aimed to detect the presence of species belonging to the Anaplasmataceae family, piroplasmas and Hepatozoon spp. DNA in blood samples of domesticated and stray cats in the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil. Between January and April 2013, whole blood samples were collected from 151 cats (54 males, 95 females and two without gender registration) in the city of Campo Grande, state of Mato Grosso do Sul, Brazil. DNA extracted from cat blood samples was submitted to conventional PCR assays for Theileria/Babesia/Cytauxzoon spp. (18S rRNA, ITS-1), Ehrlichia spp. (16S rRNA, dsb, groESL), Anaplasma spp. (16S rRNA, groESL) and Hepatozoon spp. (18S rRNA) followed by phylogenetic reconstructions. Out of 151 sampled cats, 13 (8.5%) were positive for Ehrlichia spp. closely related to Ehrlichia canis, 1 (0.66%) for Hepatozoon spp. closely related to Hepatozoon americanum and Hepatozoon spp. isolate from a wild felid, 1 (0.66%) for Cytauxzoon sp. closely related do Cytauxzoon felis, and 18 (11.9%) for Babesia/Theileria (one sequence was closely related to Babesia bigemina, eight for Babesia vogeli, five to Theileria spp. from ruminants [Theileria ovis, Theileria lestoquardi] and four to Theileria sp. recently detected in a cat). The present study showed that Ehrlichia spp., piroplasmids (B. vogeli, Theileria spp. and Cytauxzoon spp.) and, more rarely, Hepatozoon spp. circulate among stray and domesticated cats in the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil. PMID:26187416

  16. Tick-borne agents in domesticated and stray cats from the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil.

    PubMed

    André, Marcos Rogério; Herrera, Heitor Miraglia; Fernandes, Simone de Jesus; de Sousa, Keyla Cartens Marques; Gonçalves, Luiz Ricardo; Domingos, Iara Helena; de Macedo, Gabriel Carvalho; Machado, Rosangela Zacarias

    2015-09-01

    Anaplasmataceae agents, piroplasmids and Hepatozoon spp. have emerged as important pathogens among domestic and wild felines. The present work aimed to detect the presence of species belonging to the Anaplasmataceae family, piroplasmas and Hepatozoon spp. DNA in blood samples of domesticated and stray cats in the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil. Between January and April 2013, whole blood samples were collected from 151 cats (54 males, 95 females and two without gender registration) in the city of Campo Grande, state of Mato Grosso do Sul, Brazil. DNA extracted from cat blood samples was submitted to conventional PCR assays for Theileria/Babesia/Cytauxzoon spp. (18S rRNA, ITS-1), Ehrlichia spp. (16S rRNA, dsb, groESL), Anaplasma spp. (16S rRNA, groESL) and Hepatozoon spp. (18S rRNA) followed by phylogenetic reconstructions. Out of 151 sampled cats, 13 (8.5%) were positive for Ehrlichia spp. closely related to Ehrlichia canis, 1 (0.66%) for Hepatozoon spp. closely related to Hepatozoon americanum and Hepatozoon spp. isolate from a wild felid, 1 (0.66%) for Cytauxzoon sp. closely related do Cytauxzoon felis, and 18 (11.9%) for Babesia/Theileria (one sequence was closely related to Babesia bigemina, eight for Babesia vogeli, five to Theileria spp. from ruminants [Theileria ovis, Theileria lestoquardi] and four to Theileria sp. recently detected in a cat). The present study showed that Ehrlichia spp., piroplasmids (B. vogeli, Theileria spp. and Cytauxzoon spp.) and, more rarely, Hepatozoon spp. circulate among stray and domesticated cats in the city of Campo Grande, state of Mato Grosso do Sul, midwestern Brazil.

  17. Rocky Mountain Tertiary coal-basin models and their applicability to some world basins

    USGS Publications Warehouse

    Flores, R.M.

    1989-01-01

    Tertiary intermontane basins in the Rocky Mountain region of the United States contain large amounts of coal resources. The first major type of Tertiary coal basin is closed and lake-dominated, either mud-rich (e.g., North Park Basin, Colorado) or mud plus carbonate (e.g., Medicine Lodge Basin, Montana), which are both infilled by deltas. The second major type of Tertiary coal basin is open and characterized by a preponderance of sediments that were deposited by flow-through fluvial systems (e.g., Raton Basin, Colorado and New Mexico, and Powder River Basin, Wyoming and Montana). The setting for the formation of these coals varies with the type of basin sedimentation, paleotectonism, and paleoclimate. The mud-rich lake-dominated closed basin (transpressional paleotectonism and warm, humid paleoclimate), where infilled by sandy "Gilbert-type" deltas, contains thick coals (low ash and low sulfur) formed in swamps of the prograding fluvial systems. The mud- and carbonate-rich lake-dominated closed basin is infilled by carbonate precipitates plus coarse-grained fan deltas and fine-grained deltas. Here, thin coals (high ash and high sulfur) formed in swamps of the fine-grained deltas. The coarse-clastic, open basins (compressional paleotectonism and warm, paratropical paleoclimate) associated with flow-through fluvial systems contain moderately to anomalously thick coals (high to low ash and low sulfur) formed in swamps developed in intermittently abandoned portions of the fluvial systems. These coal development patterns from the Tertiary Rocky Mountain basins, although occurring in completely different paleotectonic settings, are similar to that found in the Tertiary, Cretaceous, and Permian intermontane coal basins in China, New Zealand, and India. ?? 1989.

  18. [Species from genus Eimeria observed in domestic rabbit (Oryctolagus cuniculus) feces raised at the Municipality of Campos dos Goytacazes in the State of Rio de Janeiro, Brazil].

    PubMed

    de Almeida, Adriana J; Mayen, Friederike L; de Oliveira, Francisco C R

    2006-01-01

    This study was designed to identify species of the genus Eimeria from eleven rabbit meat breeders from Campos dos Goytacazes. Fecal samples were collected from rabbits with different health conditions and consintence of feces. The following species of Eimeria were identified: E. perforans; E. magna; E. coecicola; E. irresidua; E. media; E. flavescens; E. nagpurensis; E. intestinalis, E. exigua and E. stiedae. Parasites from this genus were detected in 81.82% (9) of the rabbit meat production sites, regardless of the management and hygiene conditions. In all cases the infection was always caused from more than one species of Eimeria. PMID:17196120

  19. Umatilla Basin Habitat Improvement Project.

    SciTech Connect

    Bailey, Timothy D.

    1990-01-01

    This annual report is in fulfillment of contract obligations with Bonneville Power Administration which is the funding source for the Oregon Department of Fish and Wildlife's Umatilla Basin Habitat Improvement Project. The major activities undertaken during this report period were: procurement of 17 cooperative lease agreements with private landowners, design and layout of 8.6 miles of riparian exclosure fence and 3.0 miles of instream structures, development of five fencing contracts and six instream work contracts. Results include implementation of 10 miles of fencing and 3 miles of instream work. Other activities undertaken during this report period are: data collection from 90 habitat monitoring transects, collection and summarization of temperature data, photopoint establishment, coordination with numerous agencies and tribes and education of all age groups on habitat improvement and protection. 4 refs., 4 figs., 6 tabs.

  20. Wyoming Basin Rapid Ecoregional Assessment

    USGS Publications Warehouse

    Carr, Natasha B.; Melcher, Cynthia P.

    2015-08-28

    We evaluated Management Questions (Core and Integrated) for each species and community for the Wyoming Basin REA. Core Management Questions address primary management issues, including (1) where is the Conservation Element, and what are its key ecological attributes (characteristics of species and communities that may affect their long-term persistence or viability); (2) what and where are the Change Agents; and (3) how do the Change Agents affect the key ecological attributes? Integrated Management Questions synthesize the Core Management Questions as follows: (1) where are the areas with high landscape-level ecological values; (2) where are the areas with high landscape-level risks; and (3) where are the potential areas for conservation, restoration, and development? The associated maps and key findings for each Management Question are summa

  1. Wyoming Basin Rapid Ecoregional Assessment

    USGS Publications Warehouse

    Carr, Natasha B.; Melcher, Cynthia P.

    2015-08-28

    We evaluated Management Questions (Core and Integrated) for each species and community for the Wyoming Basin REA. Core Management Questions address primary management issues, including (1) where is the Conservation Element, and what are its key ecological attributes (characteristics of species and communities that may affect their long-term persistence or viability); (2) what and where are the Change Agents; and (3) how do the Change Agents affect the key ecological attributes? Integrated Management Questions synthesize the Core Management Questions as follows: (1) where are the areas with high landscape-level ecological values; (2) where are the areas with high landscape-level risks; and (3) where are the potential areas for conservation, restoration, and development? The associated maps and key findings for each Management Question are summarized for each Conservation Element in individual chapters. Additional chapters on landscape intactness and an REA synthesis are included.

  2. The evolution of Neoproterozoic magmatism in Southernmost Brazil: shoshonitic, high-K tholeiitic and silica-saturated, sodic alkaline volcanism in post-collisional basins.

    PubMed

    Sommer, Carlos A; Lima, Evandro F; Nardi, Lauro V S; Liz, Joaquim D; Waichel, Breno L

    2006-09-01

    The Neoproterozoic shoshonitic and mildly alkaline bimodal volcanism of Southernmost Brazil is represented by rock assemblages associated to sedimentary successions, deposited in strike-slip basins formed at the post-collisional stages of the Brasilian/Pan-African orogenic cycle. The best-preserved volcano sedimentary associations occur in the Camaquã and Campo Alegre Basins, respectively in the Sul-riograndense and Catarinense Shields and are outside the main shear belts or overlying the unaffected basement areas. These basins are characterized by alternation of volcanic cycles and siliciclastic sedimentation developed dominantly on a continental setting under subaerial conditions. This volcanism and the coeval plutonism evolved from high-K tholeiitic and calc-alkaline to shoshonitic and ended with a silica-saturated sodic alkaline magmatism, and its evolution were developed during at least 60 Ma. The compositional variation and evolution of post-collisional magmatism in southern Brazil are interpreted as the result mainly of melting of a heterogeneous mantle source, which includes garnet-phlogopite-bearing peridotites, veined-peridotites with abundant hydrated phases, such as amphibole, apatite and phlogopite, and eventually with the addition of an asthenospheric component. The subduction-related metasomatic character of post-collisional magmatism mantle sources in southern Brazil is put in evidence by Nb-negative anomalies and isotope features typical of EM1 sources.

  3. Metabolic principles of river basin organization.

    PubMed

    Rodriguez-Iturbe, Ignacio; Caylor, Kelly K; Rinaldo, Andrea

    2011-07-19

    The metabolism of a river basin is defined as the set of processes through which the basin maintains its structure and responds to its environment. Green (or biotic) metabolism is measured via transpiration and blue (or abiotic) metabolism through runoff. A principle of equal metabolic rate per unit area throughout the basin structure is developed and tested in a river basin characterized by large heterogeneities in precipitation, vegetation, soil, and geomorphology. This principle is suggested to have profound implications for the spatial organization of river basin hydrologic dynamics, including the minimization of energy expenditure known to control the scale-invariant characteristics of river networks over several orders of magnitude. Empirically derived, remarkably constant rates of average transpiration per unit area through the basin structure lead to a power law for the probability distribution of transpiration from a randomly chosen subbasin. The average runoff per unit area, evaluated for subbasins of a wide range of topological magnitudes, is also shown to be remarkably constant independently of size. A similar result is found for the rainfall after accounting for canopy interception. Allometric scaling of metabolic rates with size, variously addressed in the biological literature and network theory under the label of Kleiber's law, is similarly derived. The empirical evidence suggests that river basin metabolic activity is linked with the spatial organization that takes place around the drainage network and therefore with the mechanisms responsible for the fractal geometry of the network, suggesting a new coevolutionary framework for biological, geomorphological, and hydrologic dynamics.

  4. Petroleum potential of the Reggane Basin, Algeria

    SciTech Connect

    Boudjema, A.; Hamel, M.; Mohamedi, A.; Lounissi, R. )

    1990-05-01

    The intracratonic Reggane basin is located on the Saharan platform, southwest of Algeria. The basin covers an area of approximately 140,000 km{sup 2}, extending between the Eglab shield in the south and the Ougarta ranges in the north. Although exploration started in the early 1950s, only a few wells were drilled in this basin. Gas was discovered with a number of oil shows. The sedimentary fill, mainly Paleozoic shales and sandstones, has a thickness exceeding 5,000 m in the central part of the basin. The reservoirs are Cambrian-Ordovician, Siegenian, Emsian, Tournaisian, and Visean sandstones with prospective petrophysical characteristics. Silurian Upper Devonian and, to a lesser extent Carboniferous shales are the main source rocks. An integrated study was done to assess the hydrocarbon potential of this basin. Tectonic evolution source rocks and reservoirs distribution maturation analyses followed by kinetic modeling, and hydrogeological conditions were studied. Results indicate that gas accumulations could be expected in the central and deeper part of the basin, and oil reservoirs could be discovered on the basin edge.

  5. Submarine Landslides in Arctic Sedimentation: Canada Basin

    USGS Publications Warehouse

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Lebedova-Ivanova, N; Chapman, C.

    2016-01-01

    Canada Basin of the Arctic Ocean is the least studied ocean basin in the World. Marine seismic field programs were conducted over the past 6 years using Canadian and American icebreakers. These expeditions acquired more than 14,000 line-km of multibeam bathymetric and multi-channel seismic reflection data over abyssal plain, continental rise and slope regions of Canada Basin; areas where little or no seismic reflection data existed previously. Canada Basin is a turbidite-filled basin with flat-lying reflections correlateable over 100s of km. For the upper half of the sedimentary succession, evidence of sedimentary processes other than turbidity current deposition is rare. The Canadian Archipelago and Beaufort Sea margins host stacked mass transport deposits from which many of these turbidites appear to derive. The stratigraphic succession of the MacKenzie River fan is dominated by mass transport deposits; one such complex is in excess of 132,000 km2 in area and underlies much of the southern abyssal plain. The modern seafloor is also scarred with escarpments and mass failure deposits; evidence that submarine landsliding is an ongoing process. In its latest phase of development, Canada Basin is geomorphologically confined with stable oceanographic structure, resulting in restricted depositional/reworking processes. The sedimentary record, therefore, underscores the significance of mass-transport processes in providing sediments to oceanic abyssal plains as few other basins are able to do.

  6. Metabolic principles of river basin organization.

    PubMed

    Rodriguez-Iturbe, Ignacio; Caylor, Kelly K; Rinaldo, Andrea

    2011-07-19

    The metabolism of a river basin is defined as the set of processes through which the basin maintains its structure and responds to its environment. Green (or biotic) metabolism is measured via transpiration and blue (or abiotic) metabolism through runoff. A principle of equal metabolic rate per unit area throughout the basin structure is developed and tested in a river basin characterized by large heterogeneities in precipitation, vegetation, soil, and geomorphology. This principle is suggested to have profound implications for the spatial organization of river basin hydrologic dynamics, including the minimization of energy expenditure known to control the scale-invariant characteristics of river networks over several orders of magnitude. Empirically derived, remarkably constant rates of average transpiration per unit area through the basin structure lead to a power law for the probability distribution of transpiration from a randomly chosen subbasin. The average runoff per unit area, evaluated for subbasins of a wide range of topological magnitudes, is also shown to be remarkably constant independently of size. A similar result is found for the rainfall after accounting for canopy interception. Allometric scaling of metabolic rates with size, variously addressed in the biological literature and network theory under the label of Kleiber's law, is similarly derived. The empirical evidence suggests that river basin metabolic activity is linked with the spatial organization that takes place around the drainage network and therefore with the mechanisms responsible for the fractal geometry of the network, suggesting a new coevolutionary framework for biological, geomorphological, and hydrologic dynamics. PMID:21670259

  7. How integrated is river basin management?

    NASA Astrophysics Data System (ADS)

    Downs, Peter W.; Gregory, Kenneth J.; Brookes, Andrew

    1991-05-01

    Land and water management is increasingly focused upon the drainage basin. Thirty-six terms recently used for schemes of “integrated basin management” include reference to the subject or area and to the aims of integrated river basin management, often without allusion to the multiobjective nature. Diversity in usage of terms has occurred because of the involvement of different disciplines, of the increasing coherence of the drainage basin approach, and the problems posed in particular parts of the world. The components included in 21 different approaches are analyzed, and, in addition to showing that components related broadly to water supply, river channel, land, and leisure aspects, it is concluded that there are essentially five interrelated facets of integrated basin management that involved water, channel, land, ecology, and human activity. Two aspects not fully included in many previous schemes concern river channel changes and the dynamic integrity of the fluvial system. To clarify the terminology used, it is suggested that the term comprehensive river basin management should be used where a wide range of components is involved, whereas integrated basin management can signify the interactions of components and the dominance of certain components in the particular area. Holistic river basin management is advocated as a term representing an approach that is both fully comprehensive and integrated but also embraces the energetics of the river system and consideration of changes of river channels and of human impacts throughout the river system. The paradigm of working with the river can be extended to one of working with the river in the holistic basin context.

  8. Groundwater Mounding Beneath Stormwater Infiltration Basins

    NASA Astrophysics Data System (ADS)

    Nimmer, M.; Thompson, A. M.; Misra, D.

    2007-12-01

    An accurate understanding of groundwater mound formation is important in the proper design of stormwater infiltration basins since these basins are often required to recharge a portion of pre-development infiltration volume. Mound formation due to localized recharge may reduce the infiltration rate of the basin and the ability of the soil to filter pollutants. The goal of this research was to understand groundwater mounding and the potential for contaminant transport resulting from recharge beneath stormwater infiltration basins. A 0.10 ha infiltration basin serving a 9.4 ha residential subdivision in Oconomowoc, Wisconsin was used in this study. Subsurface conditions included sand and gravel material and a groundwater table at 2.3 m below grade. Three storm events, 4.9 cm, 2.8 cm, and 4.3 cm, between August 2006 and April 2007 were modeled using the two-dimensional numerical model HYDRUS. The calibrated model was used to evaluate hypothetical basin operation scenarios for various basin sizes, soil types, ponding depths, and water table depths. The groundwater mound intersected the basin floor in most scenarios with loamy sand and sandy loam soils, an unsaturated thickness of 1.52 m, and a ponding depth of 0.61 m. No groundwater table response was observed with ponding depths less than 0.31 m with an unsaturated zone thickness of 6.09 m. The mound height was most sensitive to hydraulic conductivity and unsaturated zone thickness. A 7.6 cm sediment layer delayed the time to reach maximum mound height, but had a minimal effect on the magnitude of the mound. Mound heights increased as infiltration basin size increased.

  9. Control of salt tectonics by young basement tectonics in Brazil`s offshore basins

    SciTech Connect

    Szatmari, P.; Mohriak, W.

    1995-08-01

    The Campos basin (offshore SE Brazil) is one of the most successful areas of oil exploration in South America. Discovered 20 years ago, its production (500,000 b/d) and reserves (2.9 billion barrels) are second only to Venezuela`s. This richness is due, to a large extent, to intense salt tectonics and the abundance of turbidites. Reactivated basement structures onshore provide a unique opportunity to understand the role of young basement tectonics in controlling salt tectonics and petroleum occurrence. The mountains of SE Brazil, over 1500 m high, formed by the reactivation of late Precambrian thrust and wrench zones under E-W compression, presumably caused by Mid-Atlantic ridge push. Coastal mountain ranges, up to 3000 m high, are limited to the segment of the Atlantic between the Vitoria-Trindade hotspot chain and the Rio Grande Rise. The coastal ranges formed as this segment of oceanic crust and adjacent continental margin were pushed WSW along a reactivated Precambrian wrench zone. To the north of this segment, salt tectonics is mostly due to basinward sliding on a tilted salt layer. Along the coastal ranges, to this is added basinward escape of the salt from beneath prograding sediments derived from the rising mountains. Extension above the salt tends to be compensated by compression farther basinward. Salt canopies, frequent in the Gulf of Mexico, occur only near the Abrolhos hotspot, where high temperatures during volcanic activity sharply reduced the viscosity of the salt.

  10. Two basins explored in Dominican Republic

    SciTech Connect

    Ellis, G.M.

    1996-04-29

    Exploration companies are exploring two tracts in separate basins of the Dominican Republic. Drilling is under way or planned in the eastern Cibao basin in the northeastern part of the country, where Petrolera Once Once SA holds a 1,001,287 ha concession, and the Azua-Bani basin in the southwester, where Mobil-Murfin holds a 2,266,197 ha concession. About 75 wells have been drilled onshore in Dominican Republic, but commercial production has not been established. This paper summarizes the exploration history and geology of the area.

  11. A geologic study of the Michigan Basin

    NASA Astrophysics Data System (ADS)

    Peterson, R. E.

    1982-05-01

    The Michigan Basin contains sediments from Cambrian through Pennsylvanian age. The geologic basin is of greatest depth in Central Michigan with approximately 15,000 ft of strata. To assess efficiently which formations have suitable reservoir characteristics to be included in the Gas Research Institute tight gas sands program, a catalog of the lower-permeability formations and their characteristics was required. The lack of geologic units that were considered to have sufficient extent reservoir characteristics or gas reserves to be of interest as blanket-like gas sands precluded a more detailed inventory and characterization. An overview of all gas productive formations in the Michigan Basin is given.

  12. Prediction of hydrocarbons in sedimentary basins

    USGS Publications Warehouse

    Harff, J.E.; Davis, J.C.; Eiserbeck, W.

    1993-01-01

    To estimate the undiscovered hydrocarbon potential of sedimentary basins, quantitative play assessments specific for each location in a region may be obtained using geostatistical methods combined with the theory of classification of geological objects, a methodology referred to as regionalization. The technique relies on process modeling and measured borehole data as well as probabilistic methods to exploit the relationship between geology (the "predictor") and known hydrocarbon productivity (the "target") to define prospective stratigraphic intervals within a basin. It is demonstrated in case studies from the oil-producing region of the western Kansas Pennsylvanian Shelf and the gas-bearing Rotliegend sediments of the Northeast German Basin. ?? 1993 International Association for Mathematical Geology.

  13. 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

  14. Stratigraphy of the Caloris basin, Mercury

    USGS Publications Warehouse

    McCauley, J.F.; Guest, J.E.; Schaber, G.G.; Trask, N.J.; Greeley, R.

    1981-01-01

    The 1300-km-diameter Caloris impact basin is surrounded by well-defined ejecta units that can be recognized from more than 1000 km, radially outward from the basin edge. A formal rock stratigraphic nomenclature is proposed for the Caloris ejecta units, which are collectively called the Caloris Group. Each of the individual formations within the Group are described and compared to similar rock units associated with the lunar Imbrium and Orientale basins. A crater degradation chronology, linked the the Caloris event, is also proposed to assist in stratigraphic correlation on a Mercury-wide basis. ?? 1981.

  15. K Basins isolation barriers summary report

    SciTech Connect

    Strickland, G.C., Westinghouse Hanford

    1996-07-31

    The 105-K East and 105-K West fuel storage basins (105-K Basins) were designed and constructed in the early 1950`s for interim storage of irradiated fuel following its discharge from the reactors. The 105-K- East and 105-K West reactor buildings were constructed first, and the associated storage basins were added about a year later. The construction joint between each reactor building structure and the basin structure included a flexible membrane waterstop to prevent leakage. Water in the storage basins provided both radiation shielding and cooling to remove decay heat from stored fuel until its transfer to the Plutonium Uranium Extraction (PUREX) Facility for chemical processing. The 105-K West Reactor was permanently shut down in February 1970; the 105-K East Reactor was permanently shut down in February 1971. Except for a few loose pieces, fuel stored in the basins at that time was shipped to the PUREX Facility for processing. The basins were then left idle but were kept filled with water. The PUREX Facility was shut down and placed on wet standby in 1972 while N Reactor continued to operate. When the N Reactor fuel storage basin began to approach storage capacity, the decision was made to modify the fuel storage basins at 105-K East and 105-K West to provide additional storage capacity. Both basins were subsequently modified (105-K East in 1975 and 105-K West in 1981) to provide for the interim handling and storage of irradiated N Reactor fuel. The PUREX Facility was restarted in November 1983 to provide 1698 additional weapons-grade plutonium for the United States defense mission. The facility was shut down and deactivated in December 1992 when the U.S. Department of Energy (DOE) determined that the plant was no longer needed to support weapons-grade plutonium production. When the PUREX Facility was shut down, approximately 2.1 x 1 06 kg (2,100 metric tons) of irradiated fuel aged 7 to 23 years was left in storage in the 105-K Basins pending a decision on

  16. YARD NO. 3 BASINS (GRAVING DOCKS), VIEW TO EASTNORTHEAST AT ...

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

    YARD NO. 3 BASINS (GRAVING DOCKS), VIEW TO EAST-NORTHEAST AT THE SOUTH END OF THE CRANEWAY AND GALLERY BETWEEN BASINS NO. 1 AND 2, LOOKING ACROSS SOUTH END OF BASIN NO. 1 (THE WESTERN-MOST BASIN) - Rosie the Riveter National Historical Park, Graving Docks, Shipyard No. 3, Richmond, Contra Costa County, CA

  17. Highly Complicated Basins of Periodic Attractors in Coupled Chaotic Maps

    NASA Astrophysics Data System (ADS)

    Inoue, M.; Nishi, Y.

    1996-03-01

    The basin structure of the coupled logistic maps is considered. It is found that a synchronous periodic attractor coexists with other periodic attractors in several regions of the parameter space. These periodic attractors have highly complicated basins which are similar to riddled basins. Basins of a roulette is also discussed.

  18. Discharge forecasts in mountain basins based on satellite snow cover mapping. [Dinwoody Creek Basin, Wyoming and the Dischma Basin, Switzerland

    NASA Technical Reports Server (NTRS)

    Martinec, J.; Rango, A. (Principal Investigator)

    1980-01-01

    The author has identified the following significant results. A snow runoff model developed for European mountain basins was used with LANDSAT imagery and air temperature data to simulate runoff in the Rocky Mountains under conditions of large elevation range and moderate cloud cover (cloud cover of 40% or less during LANDSAT passes 70% of the time during a snowmelt season). Favorable results were obtained for basins with area not exceeding serval hundred square kilometers and with a significant component of subsurface runoff.

  19. Seasonal variation of Lutzomyia longipalpis (Lutz & Neiva, 1912) (Diptera: Psychodidae: Phlebotominae) in endemic area of visceral leishmaniasis, Campo Grande, state of Mato Grosso do Sul, Brazil.

    PubMed

    Oliveira, Alessandra Gutierrez; Galati, Eunice Aparecida Bianchi; Fernandes, Carlos Eurico; Dorval, Maria Elizabeth Cavalheiros; Brazil, Reginaldo Peçanha

    2008-01-01

    The seasonal distribution of Lutzomyia longipalpis was studied in two forested and five domiciliary areas of the urban area of Campo Grande; MS, from December 2003 to November 2005. Weekly captures were carried out with CDC light traps positioned on ground and in the canopy inside a residual forest and on the edge (ground) of a woodland and in at least one of the following ecotopes in peridomiciles-a cultivated area, a chicken coop, a pigsty, a kennel, a goat and sheep shelter and an intradomicile. A total of 9519 sand flies were collected, 2666 during the first year and 6853 during the second. L. longipalpis was found throughout the 2-year period, presenting smaller peaks at intervals of 2-3 months and two greater peaks, the first in February and the second in April 2005, soon after periods of heavy rain. Only In one of the woodlands was a significant negative correlation (p<0.05) between the number of insects and temperature during the first year and the climatic factors (temperature, RHA and rain) was observed. In the domiciliary areas in four domiciles some positive correlations (p< or =0.05) occurred in relation to one or more climatic factors; however, the species shows a clear tendency to greater frequency (72%) in the rainy season than in the dry (28%). Thus, we recommend an intensification of the VL control measures applied in Campo Grande, MS, during the rainy season with a view to reducing the risk of the transmission of the disease.

  20. Abundance of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) and urban transmission of visceral leishmaniasis in Campo Grande, state of Mato Grosso do Sul, Brazil.

    PubMed

    Oliveira, Alessandra Gutierrez de; Galati, Eunice Aparecida Bianchi; de Oliveira, Orcy; de Oliveira, Gilliard Rezende; Espindola, Italo Alexander Cabello; Dorval, Maria Elizabeth Cavalheiros; Brazil, Reginaldo Peçanha

    2006-12-01

    The outspread and urbanization of visceral leishmaniasis (VL) in Campo Grande, state of Mato Grosso do Sul, lead us to undertake the present study over diversity and abundance of sand flies in the urban area to compare with previous search carried out during 1999/2000, before the identification of the disease in the human population. The captures were carried out with automatic light traps, weekly, from February 2004 to February 2005 on three sites including a forested area (Zé Pereira), two peridomicilies (shelters of domestic animals and cultivation areas), and intradomicilie. In the present study 110 collections were obtained during 13 months for 1320 h of collections, resulting in 5004 specimens, 3649 males and 1355 females belonging to the 20 following species: Brumptomyia avellari, Brumptomyia sp., Bichromomyia flaviscutellata, Evandromyia lenti, E. termitophila, E. cortelezzii, E. borrouli, Lutzomyia sp., L. longipalpis, Micropygomyia quinquefer, N. antunesi, N. whitmani, Pintomyia christenseni, Pi. damascenoi, Psathyromyia aragaoi, Ps. campograndensis, Ps. hermanlenti, Ps. shannoni, Pychodopygus claustrei, and Sciopemyia sordellii. L. longipalpis was the most abundant species in the anthropic environment with 92.22% of the captures. This shows an increase of sixty times in the density of L. longipalpis compared to the last sand fly evaluation in 1999/2000. The high density of L. longipalpis in Campo Grande is the main factor of risk in transmission of the disease to human in the urban area. The capture of N. antunesi, typical specie from Amazonian region, in Mato Grosso do Sul is reported for the first time.

  1. Death of a carbonate basin: The Niagara-Salina transition in the Michigan basin

    SciTech Connect

    Leibold, A.W.; Howell, P.D. )

    1991-03-01

    The A-O Carbonate in the Michigan basin comprises a sequence of laminated calcite/anhydrite layers intercalated with bedded halite at the transition between normal marine Niagaran carbonates and lower Salina Group evaporites. The carbonate/anhydrite interbeds represent freshing events during initial evaporative concentration of the Michigan basin. Recent drilling in the Michigan basin delineates two distinct regions of A-O Carbonate development: a 5 to 10 m thick sequence of six 'laminites' found throughout most of the western and northern basin and a 10 to 25 m thick sequence in the southeastern basin containing both thicker 'laminates' and thicker salt interbeds. Additionally, potash deposits of the overlying A-1 evaporite unit are restricted to the northern and western basin regions. The distribution of evaporite facies in these two regions is adequately explained by a source of basin recharge in the southeast-perhaps the 'Clinton Inlet' of earlier workers. This situation suggest either that: (1) the source of basin recharge is alternately supplying preconcentrated brine and more normal marine water, or (2) that the basin received at least two distinct sources of water during A-O deposition.

  2. BASIN STRUCTURE FROM TWO-DIMENSIONAL SEISMIC REFLECTION DATA, CRAZY MOUNTAINS BASIN, MONTANA

    SciTech Connect

    David J. Taylor

    2003-08-01

    Some 140 miles of multichannel seismic reflection data, acquired commercially in the 1970's, were reprocessed by the U.S. Geological Survey in late 2000 and early 2001 to interpret the subsurface geology of the Crazy Mountains Basin, an asymmetric Laramide foreland basin located in south-central Montana. The seismic data indicate that the northwestern basin margin is controlled by a thrust fault that places basement rocks over a thick (22,000 feet) sequence of Paleozoic and Mesozoic sedimentary rocks to the south. From the deep basin trough, Paleozoic through Tertiary rocks slope gently upward to the south and southeast. The northern boundary of the basin, which is not imaged well by the seismic data, appears to be folded over a basement ridge rather than being truncated against a fault plane. Seismic data along the basin margin to the south indicate that several fault controlled basement highs may have been created by thin-skinned tectonics where a series of shallow thrust faults cut Precambrian, Paleozoic, and early Mesozoic rocks, whereas, in contrast, Cretaceous and Tertiary strata are folded. The data are further interpreted to indicate that this fault-bounded asymmetric basin contains several structures that possibly could trap hydrocarbons, provided source rocks, reservoirs, and seals are present. In addition, faults in the deep basin trough may have created enough fracturing to enhance porosity, thus developing ''sweet spots'' for hydrocarbons in basin-centered continuous gas accumulations.

  3. VIEW TO EAST OF THE NORTH END OF BASIN NO. ...

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

    VIEW TO EAST OF THE NORTH END OF BASIN NO. 1 (THE WESTERN-MOST BASIN) SHOWING THE CRANEWAY AND GALLERY BETWEEN BASINS NO. 1 AND 2. BASSWOOD BUOY TENDER AND THREE SMALL VESSELS ARE BERTHED IN BASIN NO. 1. LARGER VESSELS ARE BERTHED IN BASINS TO THE EAST, SEEN IN BACKGROUND - Rosie the Riveter National Historical Park, Graving Docks, Shipyard No. 3, Richmond, Contra Costa County, CA

  4. K-Basins S/RIDS

    SciTech Connect

    Watson, D.J.

    1997-08-01

    The Standards/Requirements Identification Document (S/RID) is a list of the Environmental, Safety, and Health (ES{ampersand}H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility.

  5. K-Basins S/RIDS

    SciTech Connect

    Watson, D.J.

    1995-09-22

    The Standards/Requirements Identification Document(S/RID) is a list of the Environmental, Safety, and Health (ES&H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility

  6. Hydro Impact Basin Ribbon-Cutting Ceremony

    NASA Video Gallery

    August 9, 2011 -- Ribbon-cutting ceremony for the Hydro Impact Basin at NASA's Langley Research Center in Hampton, Va. The HIB expands NASA's capability to test and certify future spacecraft for wa...

  7. Stratigraphy of the Caloris basin, Mercury

    NASA Astrophysics Data System (ADS)

    McCauley, J. F.; Guest, J. E.; Schaber, G. G.; Trask, N. J.; Greeley, R.

    1981-08-01

    A formal rock stratigraphic nomenclature in proposed for the ejecta units of the 1300-km diameter Caloris impact basin of Mercury. The ejecta units can be recognized for more than 1000 km radially outward from the basin edge, and are collectively called the Caloris Group. The formations recognized within the Caloris Group include: (1) the Caloris Montes; (2) the Nervo; (3) the Odin; and (4) two Van Eyck Formations, one with lineated facies and the other with secondary crater facies. It is shown that of the craters in the 30-100-km size range superposed on the Caloris ejecta assemblage, most are of the c(4) and c(5) type. The youngest craters are assigned the highest subscript numbers. If other basins and craters can be tied into the Caloris basin over the rest of Mercury using data from Mariner 10, the stratigraphy described may help establish a time stratigraphy consisting of formal systems and periods in the history of Mercury.

  8. Pacific Basin Communication Study, volume 2

    NASA Technical Reports Server (NTRS)

    Young, E. L.; Hurd, J. N.

    1981-01-01

    Users' meeting summary report, chronology of visits, economic data for forum countries, techniques used in the study, communication choices, existing resources in the Pacific Basin, and warc 79 region 3 rules and regulations were presented in volume 2.

  9. Appalachian basin bibliography. Topical report, March 1994

    SciTech Connect

    Picciano, L.; Armstrong, T.S.

    1994-03-01

    More than 120 Gas Research Institute reports on gas exploration and production in the Appalachian Basin are listed. They cover geology and reservoir engineering in three gas producing formations: shales, tight gas sands, and coal seams.

  10. Petroleum generation in the Morocco Basin

    SciTech Connect

    Geodekyan, A.A.; Simonenko, L.A.; Trotsyuk, V.Ya.

    1987-12-01

    Passive-margin sedimentary basins, despite their geologic similarities, differ substantially in their oil and gas reserves and in the distributions of these areally and in the section. Evidently, the level of hydrocarbon potential is controlled by differences in the size and history of the zone of petroleum generation. This conclusion was originally drawn from historical methods applied to various basins. To refine the conclusions and define the significance of the individual factors controlling hydrocarbon generation, it is of interest to examine the petroleum potential for a fairly extensive system. Here the authors consider the Morocco basin, in the passive-margin basin system of the East Atlantic, which has very scanty oil and gas reserves. The proven reserves at the start of 1978 were only 20.55 million metric tons of oil and 1.2 billion m/sup 3/ of gas. 16 references.

  11. Overflow of Radioactive Water from K Basins

    SciTech Connect

    RITTMANN, P.D.

    1999-10-06

    This report documents the dose calculations for the postulated K Basin overflow accident using current methods to model the environmental doses for radioactive releases into the Columbia River and the air.

  12. Fishes of the White River basin, Indiana

    USGS Publications Warehouse

    Crawford, Charles G.; Lydy, Michael J.; Frey, Jeffrey W.

    1996-01-01

    Since 1875, researchers have reported 158 species of fish belonging to 25 families in the White River Basin. Of these species, 6 have not been reported since 1900 and 10 have not been reported since 1943. Since the 1820's, fish communities in the White River Basin have been affected by the alteration of stream habitat, overfishing, the introduction of non-native species, agriculture, and urbanization. Erosion resulting from conversion of forest land to cropland in the 1800's led to siltation of streambeds and resulted in the loss of some silt-sensitive species. In the early 1900's, the water quality of the White River was seriously degraded for 100 miles by untreated sewage from the City of Indianapolis. During the last 25 years, water quality in the basin has improved because of efforts to control water pollution. Fish communities in the basin have responded favorably to the improved water quality.

  13. River Basin Standards Interoperability Pilot

    NASA Astrophysics Data System (ADS)

    Pesquer, Lluís; Masó, Joan; Stasch, Christoph

    2016-04-01

    There is a lot of water information and tools in Europe to be applied in the river basin management but fragmentation and a lack of coordination between countries still exists. The European Commission and the member states have financed several research and innovation projects in support of the Water Framework Directive. Only a few of them are using the recently emerging hydrological standards, such as the OGC WaterML 2.0. WaterInnEU is a Horizon 2020 project focused on creating a marketplace to enhance the exploitation of EU funded ICT models, tools, protocols and policy briefs related to water and to establish suitable conditions for new market opportunities based on these offerings. One of WaterInnEU's main goals is to assess the level of standardization and interoperability of these outcomes as a mechanism to integrate ICT-based tools, incorporate open data platforms and generate a palette of interchangeable components that are able to use the water data emerging from the recently proposed open data sharing processes and data models stimulated by initiatives such as the INSPIRE directive. As part of the standardization and interoperability activities in the project, the authors are designing an experiment (RIBASE, the present work) to demonstrate how current ICT-based tools and water data can work in combination with geospatial web services in the Scheldt river basin. The main structure of this experiment, that is the core of the present work, is composed by the following steps: - Extraction of information from river gauges data in OGC WaterML 2.0 format using SOS services (preferably compliant to the OGC SOS 2.0 Hydrology Profile Best Practice). - Model floods using a WPS 2.0, WaterML 2.0 data and weather forecast models as input. - Evaluation of the applicability of Sensor Notification Services in water emergencies. - Open distribution of the input and output data as OGC web services WaterML, / WCS / WFS and with visualization utilities: WMS. The architecture

  14. Biomonitoring the genotoxic potential of the air on Tradescantia pallida var. purpurea under climatic conditions in the Sinos River basin, Rio Grande do Sul, Brazil.

    PubMed

    Cassanego, M B B; Sasamori, M H; Petry, C T; Droste, A

    2015-11-01

    The present study evaluated the genotoxic effects of the atmospheric air on Tradescantia pallida var. purpurea in urban areas with different intensities of vehicular traffic and in riparian forest fragments in the Sinos River Basin (Rio Grande do Sul, Brazil), considering the influence of climatic conditions prevailing in these environments. Bimonthly, from May 2012 to March 2013, cuttings with flower buds were exposed for 8 h in urban and riparian forest environments in the municipalities of Caraá, Taquara and Campo Bom in the upper, middle and lower sections, respectively, of the Sinos River Basin. Simultaneously, negative controls were made and climatic data were recorded. Micronuclei (MCN) frequencies were determined in young tetrads of pollen mother cells and expressed as MCN/100 tetrads. Significantly higher MCN frequencies were observed in buds exposed in urban and riparian forest environments in Taquara (up to 7.23 and 4.80, respectively) and Campo Bom (up to 4.90 and 4.23, respectively) than in buds exposed in Caraá (up to 2.90 and 2.50, respectively), in the majority of samplings, and in relation to the negative control (up to 1.93) in all months. Over the course of the period monitored, there were significant variations in MCN frequencies at all sampling points, with the exception of the urban environment in Caraá. For the urban environments, relation between the MCN frequency, vehicular traffic and mean temperature was observed. For the riparian forest fragments, there was no association between MCN frequency and climatic factors. Tradescantia pallida var. purpurea can be considered a useful tool to point out areas with increased atmospheric pollution, since the exposure of plants under severe climatic conditions is avoided to minimize their negative influence on the formation of micronuclei.

  15. Paraguay river basin response to seasonal rainfall

    NASA Astrophysics Data System (ADS)

    Krepper, Carlos M.; García, Norberto O.; Jones, Phil D.

    2006-07-01

    The use of river flow as a surrogate to study climatic variability implies the assumption that changes in rainfall are mirrored and likely amplified in streamflow. This is probably not completely true in large basins, particularly those that encompass different climatic regions, like the Paraguay river basin. Not all the signals present in precipitation are reflected in river flow and vice versa. The complex relationship between precipitation and streamflow could filter some signals and introduce new oscillatory modes in the discharge series. In this study the whole basin (1 095 000 km2) was divided into two sub-basins. The upper basin is upstream of the confluence with the River Apa and the lower basin is between the Apa river confluence and the Puerto Bermejo measuring station. The rainfall contribution shows a clear wet season from October to March and a dry season from April to September. A singular spectrum analysis (SSA) shows that there are trends in rainfall contributions over the upper and lower basins. Meanwhile, the lower basin only presents a near-decadal cycle (T 10 years). To determine the flow response to seasonal rainfall contributions, an SSA was applied to seasonal flow discharges at Puerto Bermejo. The seasonal flows, Q(t)O-M and Q(t)A-S, present high significant modes in the low-frequency band, like positive trends. In addition, Q(t)O-M presents a near-decadal mode, but only significant at the 77% level for short window lengths (M ≤ 15 years). Really, the Paraguay river flow is not a good surrogate to study precipitation variation. The low-frequency signals play an important role in the flow behaviour, especially during extreme events from the second half of the last century onwards.

  16. Microbiology of spent nuclear fuel storage basins.

    PubMed

    Santo Domingo, J W; Berry, C J; Summer, M; Fliermans, C B

    1998-12-01

    Microbiological studies of spent nuclear fuel storage basins at Savannah River Site (SRS) were performed as a preliminary step to elucidate the potential for microbial-influenced corrosion (MIC) in these facilities. Total direct counts and culturable counts performed during a 2-year period indicated microbial densities of 10(4) to 10(7) cells/ml in water samples and on submerged metal coupons collected from these basins. Bacterial communities present in the basin transformed between 15% and 89% of the compounds present in Biologtrade mark plates. Additionally, the presence of several biocorrosion-relevant microbial groups (i.e., sulfate-reducing bacteria and acid-producing bacteria) was detected with commercially available test kits. Scanning electron microscopy and X-ray spectra analysis of osmium tetroxide-stained coupons demonstrated the development of microbial biofilm communities on some metal coupons submerged for 3 weeks in storage basins. After 12 months, coupons were fully covered by biofilms, with some deterioration of the coupon surface evident at the microscopical level. These results suggest that, despite the oligotrophic and radiological environment of the SRS storage basins and the active water deionization treatments commonly applied to prevent electrochemical corrosion in these facilities, these conditions do not prevent microbial colonization and survival. Such microbial densities and wide diversity of carbon source utilization reflect the ability of the microbial populations to adapt to these environments. The presumptive presence of sulfate-reducing bacteria and acid-producing bacteria and the development of biofilms on submerged coupons indicated that an environment for MIC of metal components in the storage basins may occur. However, to date, there has been no indication or evidence of MIC in the basins. Basin chemistry control and corrosion surveillance programs instituted several years ago have substantially abated all corrosion mechanisms.

  17. Critically safety evaluation for K Basins sandfilters

    SciTech Connect

    Wittekind, W.D.

    1994-10-01

    Criticality safety for K Basins sandfilters was considered. No credible normal or off-normal scenarios were determined which could compromise criticality safety and result in a K{sub eff} {>=} 0.98. The conclusion is that, due to the physical form and isotopic distribution of the fissionable material, there is no possibility of a nuclear criticality in the sandfilter. For this reason, there is no need for a criticality alarm system for the K Basins sandfilters.

  18. Ordovician chitinozoan zones of Great Basin

    SciTech Connect

    Hutter, T.J.

    1987-08-01

    Within the Basin and Range province of the Great Basin of the western US, Ordovician chitinozoans have been recovered in two major lithic facies; the western eugeosynclinal facies and the eastern miogeosynclinal facies. Chitinozoans recovered from these facies range in age from Arenig to Ashgill. Extensive collections from this area make possible the establishment of chitinozoan faunal interval zones from the Ordovician of this area. Selected species of biostratigraphic value include, in chronostratigraphic order, Lagenochitina ovoidea Benoit and Taugourdeau, 1961, Conochitina langei Combaz and Peniguel, 1972, Conochitinia poumoti Combaz and Penique, Desmochitina cf. nodosa Eisenack, 1931, Conochitina maclartii Combaz and Peniguel, 1972, Conochitina robusta Eisenack, 1959, Angochitina capitallata Eisenack, 1937, Sphaerochitina lepta Jenkins. 1970, and Ancyrochitina merga Jenkins, 1970. In many cases, these zones can be divided into additional sub-zones using chitinozoans and acritarchs. In all cases, these chitinozoan faunal zones are contrasted with established American graptolite zones of the area, as well as correlated with British standard graptolite zones. The composition of these faunas of the western US Great Basin is similar to that of the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico, to which direct comparisons have been made. There also appears to be a great similarity with the microfaunas and microfloras of the Ordovician of the Canning basin of western Australia. The Ordovician chitinozoan faunal interval zones established for the Basin and Range province of the Great Basin of the western US also appear to be applicable to the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico.

  19. Assessment of undiscovered carboniferous coal-bed gas resources of the Appalachian Basin and Black Warrior Basin Provinces, 2002

    SciTech Connect

    Milici, R.C.; Hatch, J.R.

    2004-09-15

    Coalbed methane (CBM) occurs in coal beds of Mississippian and Pennsylvanian (Carboniferous) age in the Appalachian basin, which extends almost continuously from New York to Alabama. In general, the basin includes three structural subbasins: the Dunkard basin in Pennsylvania, Ohio, and northern West Virginia; the Pocahontas basin in southern West Virginia, eastern Kentucky, and southwestern Virginia; and the Black Warrior basin in Alabama and Mississippi. For assessment purposes, the Appalachian basin was divided into two assessment provinces: the Appalachian Basin Province from New York to Alabama, and the Black Warrior Basin Province in Alabama and Mississippi. By far, most of the coalbed methane produced in the entire Appalachian basin has come from the Black Warrior Basin Province. 8 refs., 1 fig., 1 tab.

  20. Interpretation of magnetic anomalies over the Grenada Basin

    NASA Astrophysics Data System (ADS)

    Bird, Dale E.; Hall, Stuart A.; Casey, John F.; Millegan, Patrick S.

    1993-10-01

    The Grenada Basin is a back arc basin located near the eastern border of the Caribbean Plate. The basin is bounded on the west by the north-south trending Aves Ridge (a remnant island arc) and on the east by the active Lesser Antilles island arc. Although this physiography suggests that east-west extension formed the basin, magnetic anomalies over the basin exhibit predominantly east-west trends. If the observed magnetic anomalies over the basin are produced by seafloor spreading, then the orientation of extension is complex. Extension in back arc basins is roughly normal to the trench, although some basins exhibit oblique extension. Present models for the formation of the Grenada Basin vary from north-south extension through northeast-southwest extension to east-west extension. An interpretation of magnetic anomalies over the Grenada Basin supports basin development by nearly east-west extension. Low amplitude magnetic anomaly trends subparallel to the island arc magnetic anomaly trends over the southern part of the basin and the results of forward three-dimensional (3-D) magnetic modeling are consistent with this conclusion. Late Cenozoic tectonic movements may have been responsible for disrupting the magnetic signature over the northern part of the basin. On the basis of our 3-D analysis, we attribute the prominent east-west trending anomalies of the Grenada Basin to fracture zones formed during seafloor spreading at low latitude. This east-west trend is not interpreted as indicating north-south extension of the basin.

  1. Geothermal resources of California sedimentary basins

    USGS Publications Warehouse

    Williams, C.F.; Grubb, F.V.; Galanis, S.P.

    2004-01-01

    The 2004 Department of Energy (DOE) Strategic Plan for geothermal energy calls for expanding the geothermal resource base of the United States to 40,000 MW of electric power generating potential. This will require advances in technologies for exploiting unconventional geothermal resources, including Enhanced Geothermal Systems (EGS) and geopressured geothermal. An investigation of thermal conditions in California sedimentary basins through new temperature and heat flow measurements reveals significant geothermal potential in some areas. In many of the basins, the combined cooling effects of recent tectonic and sedimentary processes result in relatively low (<60 mW/m2) heat flow and geothermal gradients. For example, temperatures in the upper 3 km of San Joaquin, Sacramento and Ventura basins are typically less than 125??C and do not reach 200??c by 5 km. By contrast, in the Cuyama, Santa Maria and western Los Angeles basins, heat flow exceeds 80 mW/m2 and temperatures near or above 200??C occur at 4 to 5 km depth, which represents thermal conditions equivalent to or hotter than those encountered at the Soultz EGS geothermal site in Europe. Although the extractable geothermal energy contained in these basins is not large relative to the major California producing geothermal fields at The Geysers or Salton Sea, the collocation in the Los Angeles basin of a substantial petroleum extraction infrastructure and a major metropolitan area may make it attractive for eventual geothermal development as EGS technology matures.

  2. Lunar basin formation and highland stratigraphy

    NASA Technical Reports Server (NTRS)

    Howard, K. A.; Wilhelms, D. E.; Scott, D. H.

    1974-01-01

    Multiring impact basins, formed after solidification of the lunar crust, account for most or all premare regional deposits and structures expressed in the lunar landscape and for major topographic and gravity variations. A fresh basin has two or more concentric mountain rings, a lineated ejecta blanket, and secondary impact craters. Crackled material on the floor may be impact melt. The ejecta blanket was emplaced at least partly as a ground-hugging flow and was probably hot. A suggested model of basin formation is that the center lifts up and the rings form by inward collapse during evisceration. The resulting basin is shallow and has a central uplift of the mantle. This results in a central gravity high and a ring low. Later flooding by mare basalt has since modified most near side basins. Highland deposits of plains, furrowed and pitted terrain, and various hills, domes, and craters that were interpreted before the Apollo missions as being volcanic can now be interpreted as being basin related.

  3. The basins on the Argentine continental margin

    SciTech Connect

    Urien, C.M.

    1996-08-01

    After the stabilization of the central Gondwana Craton, orogenic belts were accreted, as a result of convergence events and an extensive passive margin developed in southwestern Gondwana. Thermal subsidence in Parana, Karoo-Ventania basins and the Late Paleozoic-Early Mesozoic rifts, were modified by the Gondwana breakup and the South Atlantic opening. Early Paleozoic marine transgressions deposited the Table Mountain Group in Ventania. In southwestern Patagonia foreland clastics were deposited. Magmatic arcs and marine units indicate a tectonic trough was formed, alternating with continental sequences, over Late Paleozoic metamorphics and intrusives, resulting from plastered terrains along the Gondwana margin. In Patagonia, Permo-Carboniferous continental and glacio marine clastics infill the basins, while in Ventania, paralic sequences, grade from neritic to continental to the northeast, extending beneath the continental margin. The Triassic-Jurassic rift basins progressed onto regional widespread acid lavas and were infilled by lagoonal organic-rich sequences. Early drift phase built basins transverse to the margin, with fluvio-lacustrine sequences: Salado, Colorado, Valdes-Rawson, San Julian and North Malvinas intracratonic basins, which underwent transtensional faulting. Post-Oxfordian to Neocomian brackish sequences, onlapped the conjugate basins during the margin`s drift, with petroleum systems, as in Austral and Malvinas. In the Valanginian, basic extrusions commenced to form on the continental border, heralding the oceanic phase. Due to thermal subsidence, offlaping sediments prograded onto the remaining half-grabens. Several petroleum systems, proven and hypothetical, are identified in this region.

  4. Bison basin, central Wyoming - geologic overview

    SciTech Connect

    Pinnell, M.L.

    1984-07-01

    The northeastern part of the Great Divide basin is a separate, unique, and until recently, little-explored subbasin sometimes called the Bison basin. It is bounded by the Wind River Mountains, Sweetwater-Granite Mountain foreland uplift, Lost Soldier-Wertz structure, and a little-studied very positive east-west structural arch approximately coincident with the Sweetwater-Fremont county line. A comprehensive seismic, Landsat, and subsurface geologic examination or, better, dissection of the Bison basin was initiated in 1978. Numerous oil and gas prospects were delineated by this study. Since this small, 12 by 40 mi (19 by 64 km) basin is bordered by known reserves of 260 million bbl of oil and 90 million bcf of gas, these prospects proved to be a popular target of the drill bit. At least one of these prospects appears to be productive; others are currently being drilled. The presence of major east-west wrench faults, a well-documented foreland uplift, until recently undrilled surface and subsurface structures, faults with throw measured in tens of thousands of feet, and an oil seep indicate possible additional hydrocarbon potential in the Bison basin that could exceed presently known reserves. Currently drilling wells and abundant already acquired reflection seismic data are the beginning step in an ongoing exploration program of an interesting, complex, and rewarding small basin with a lot of promise.

  5. Hydrological Modelling of Ganga River basin.

    NASA Astrophysics Data System (ADS)

    Anand, J.; Gosain, A. K.; Khosa, R.

    2015-12-01

    Application of a hydrological model, Soil and Water Assessment Tool (SWAT) to the Ganga basin having a total drainage area of around 1.08 M sq. km extending over Tibet, Nepal, India and Bangladesh has been made. The model is calibrated to determine the spatial deviations in runoff at sub-basin level, and to capture the water balance of the river basin. Manual calibration approach was used for calibrating the SWAT model by following multi-step procedure to get to the realistic present situation as close as possible. Simulations were then further made with and without proposed future projects to obtain various scenarios. The various statistical parameters used for the evaluation of the monthly runoff simulation showed that SWAT performed well in mimicking the monthly stream flow for Ganga River basin. The model under predicted the flows in the non-perennial region during non-monsoon season, due to low rainfall and regulated flows and seepage taking place from the reservoirs. The impacts of the interventions, both existing as well as proposed, on the water balance of the basin were evaluated and quantified. The derived results suggest that there is a substantial reduction in overall water resources availability in the study basin on account of the current level of development and further, future developments, as are being proposed, may require a careful study of their potential impact on currently sanctioned water use. The present study showcases that efficacy of the model for simulating the stream flow is admirable.

  6. The East Falcon Basin: Its Caribbean roots

    SciTech Connect

    Bartok, P.; Boesi, T.

    1996-08-01

    The East Falcon Basin has been described persistently in the context of the Maracaibo Basin tectonic framework. It is the objective of the present study to demonstrate that the Falcon Basin is, in effect, a Caribbean basin juxtaposed on South America and affected by Caribbean tectonics. The oldest rocks outcropping in the region are Late Paleozoic metamorphic and igneous rocks rafted from northcentral Colombia, Middle Jurassic ophiolite complexes, sediments and metasediments and Cretaceous ophiolites transported by a melange of late Cretaceous to early Tertiary sediments. The south vergence of the Caribbean Nappe province has been documented and extends to the present limit of the Andean uplift and to the southern limit of the Coastal Range. The migrating foredeep that developed during the Paleocene-Eocene deposited dominantly basinal shales and thin sandstones. During the Oligocene the Caribbean faults of the Oca system and conjugates began with a dominantly transtensional regime becoming progressively transpressional by Miocene time. The facies development of the Oligocene-Miocene documents the tectonic history. Unique blocks remained as resistant blocks creating ramparts and modifying the basin configuration. During transpression northward-verging thrusting progressively migrated towards the present coastline. The most evident structures of the region are Caribbean in affinity and combined with the sedimentary history of the region can serve to unravel the complex Caribbean-South American plate interaction.

  7. Thermal evolution of the Newark basin

    SciTech Connect

    Huntoon, J.E. ); Furlong, K.P. )

    1992-09-01

    A one-dimensional conductive thermal model is used to calculate the transient thermal history of the Newark basin, a Triassic-Jurassic continental rift basin in the eastern United States that formed during the separation of North America and Africa. The model accounts for deposition, erosion, igneous activity, lithology-dependent variations in thermal conductivity, depth-dependent radiogenic heat production, and changes in heat flow through time. A burial and erosion history for the Newark basin is constructed for the modeling, including changes in heat flow through time, emplacement of Jurassic lava flows at the surface, and emplacement of the Palisades still at depth. Vitrinite-reflectance values and apatite and zircon fission-track ages, for units of both Triassic and Jurassic age, are used to constrain the models. Use of two different data sets greatly limits the number and types of models that can reproduce the observed data. Modeling results indicate that initial formation of the Newark basin is not coincident in time with a thermal event. Elevated heat flow (on the order of 130 mW/m[sup 2] in the models) did affect the basin during its evolution, however, and was associated with igneous activity (at approximately 201-199.5 Ma in the models). Results of the modeling also indicate that the original sedimentary package in the Newark basin was approximately 2.5 km thicker than today.

  8. 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.

  9. Mesozoic evolution of the Amu Darya basin

    NASA Astrophysics Data System (ADS)

    Brunet, Marie-Françoise; Ershov, Andrey; Korotaev, Maxim; Mordvintsev, Dmitriy; Barrier, Eric; Sidorova, Irina

    2014-05-01

    This study, granted by the Darius Programme, aims at proposing a model of tectono-stratigraphic evolution of the Amu Darya basin since the Late Palaeozoic and to understand the relationship with the nearby basins. The Amu Darya basin, as its close eastern neighbour, the Afghan-Tajik basin, lies on the Turan platform, after the closure of the Turkestan Ocean during the Late Paleozoic. These two basins, spread on mainly lowlands of Turkmenistan, southwest Uzbekistan, Tajikistan, and northern Afghanistan, are separated from one another by the South-Western Gissar meganticline, where series of the northern Amu Darya margin are outcropping. The evolution is closely controlled by several periods of crustal thinning (post-collision rifting and back-arc extension), with some marine incursions, coming in between accretions of continental blocks and collisions that succeeded from the Late Triassic-Early Jurassic (Eo-Cimmerian orogeny) to the Cenozoic times. These orogenies controlled the deposition of thick clastics sequences, and the collision of the Indian Plate with Eurasia strongly deformed the sedimentary cover of the Afghan-Tajik basin. The more than 7 km thick Meso-Cenozoic sedimentary succession of the Amu Darya basin, lies on a complex system of rifts and blocks. Their orientation and age (late Permian, Triassic?) are not well known because of deep burial. The north-eastern margin, with the Bukhara (upper margin) and Chardzhou steps, is NW oriented, parallel to the Paleozoic Turkestan suture. The orientation bends to W-E, in the part of the Gissar situated to the North of the Afghan-Tajik basin. This EW trending orientation prevails also in the south(-eastern) margin of the basin (series of North Afghanistan highs) and in the Murgab depression, the south-eastern deepest portion of the Amu Darya basin. It is in this area and in the eastern part of the Amu Darya basin that the Jurassic as well as the lower Cretaceous sediments are the thickest. The south-western part

  10. Estimating tectonic history through basin simulation-enhanced seismic inversion: Geoinformatics for sedimentary basins

    USGS Publications Warehouse

    Tandon, K.; Tuncay, K.; Hubbard, K.; Comer, J.; Ortoleva, P.

    2004-01-01

    A data assimilation approach is demonstrated whereby seismic inversion is both automated and enhanced using a comprehensive numerical sedimentary basin simulator to study the physics and chemistry of sedimentary basin processes in response to geothermal gradient in much greater detail than previously attempted. The approach not only reduces costs by integrating the basin analysis and seismic inversion activities to understand the sedimentary basin evolution with respect to geodynamic parameters-but the technique also has the potential for serving as a geoinfomatics platform for understanding various physical and chemical processes operating at different scales within a sedimentary basin. Tectonic history has a first-order effect on the physical and chemical processes that govern the evolution of sedimentary basins. We demonstrate how such tectonic parameters may be estimated by minimizing the difference between observed seismic reflection data and synthetic ones constructed from the output of a reaction, transport, mechanical (RTM) basin model. We demonstrate the method by reconstructing the geothermal gradient. As thermal history strongly affects the rate of RTM processes operating in a sedimentary basin, variations in geothermal gradient history alter the present-day fluid pressure, effective stress, porosity, fracture statistics and hydrocarbon distribution. All these properties, in turn, affect the mechanical wave velocity and sediment density profiles for a sedimentary basin. The present-day state of the sedimentary basin is imaged by reflection seismology data to a high degree of resolution, but it does not give any indication of the processes that contributed to the evolution of the basin or causes for heterogeneities within the basin that are being imaged. Using texture and fluid properties predicted by our Basin RTM simulator, we generate synthetic seismograms. Linear correlation using power spectra as an error measure and an efficient quadratic

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

    NASA Astrophysics Data System (ADS)

    Bahlburg, H.

    2015-12-01

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

  12. Active transtensional intracontinental basins: Walker Lane in the western Great Basin

    USGS Publications Warehouse

    Jayko, Angela S.; Bursik, Marcus

    2012-01-01

    The geometry and dimensions of sedimentary basins within the Walker Lane are a result of Plio-Pleistocene transtensive deformation and partial detachment of the Sierra Nevada crustal block from the North American plate. Distinct morpho-tectonic domains lie within this active transtensive zone. The northeast end of the Walker Lane is partly buried by active volcanism of the southern Cascades, and adjacent basins are filled or poorly developed. To the south, the basin sizes are moderate, 25–45km × 15–10 km, with narrow 8-12km wide mountain ranges mainly oriented N-S to NNE. These basins form subparallel arrays in discrete zones trending about 300° and have documented clockwise rotation. This is succeeded to the south by a releasing stepover domain ∼85-100km wide, where the basins are elongated E-W to ENE, small (∼15-30km long, 5-15km wide), and locally occupied by active volcanic centers. The southernmost part of the Walker Lane is structurally integrated, with high to extreme relief. Adjacent basins are elongate, 50-200km long and ∼5 -20km wide. Variations in transtensive basin orientations in the Walker Lane are largely attributable to variations in strain partitioning. Large basins in the Walker Lane have 2-6km displacement across basin bounding faults with up to 3 km of clastic accumulation based on gravity and drill hole data. The sedimentary deposits of the basins may include interbedded volcanic deposits with bimodal basaltic and rhyolitic associations. The basins may include lacustrine deposits that record a wide range of water chemistry from cold fresh water conditions to saline-evaporative

  13. Marcelina formation study - Maracaibo basin

    SciTech Connect

    D`Arlach, C.; Peralta, J.; Murillo, R.

    1996-08-01

    Recent development activity onshore, west of the Maracaibo Lake, has led to a better understanding of the Paleocene Marcelina formation in the basin. The Marcelina formation is divided into two sections, an upper coal dominated interval and a lower sand/claystone interval. The sandstone reservoir section consists of a number of fining upward sequences deposited in a fluvial environment. Laterally the section evolves to a shallow marine shaly and carbonatic section, or is truncated by a regional unconformity, being missing over much of the Lake area. The Marcelina sands are only commercially productive in the Alturitas Field, where oil is found in a combined stratigraphic/structural trap. This paper focuses on two aspects of the Marcelina. First, the study incorporates the field data into a regional framework to investigate the possibility of similar plays in the studied area. Second, the study integrates geology and engineering data to examine the Marcelina as a reservoir unit to optimize field development and increase the oil recovery efficiency. Information from seismic, logs, cores, reservoir pressures, and fluids is used to understand the depositional model and the field complexity. The study provides a model, supported by extensive data, which may help to develop other potential discoveries in the west coast area.

  14. 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.

  15. The Deep Structure of Lunar Basins: Clues to the Understanding of Basin Formation and Modification

    NASA Technical Reports Server (NTRS)

    Bratt, S. R.; Solomon, S. C.; Head, J. W.; Thurber, C. H.

    1985-01-01

    Basin excavation has played a major role in shaping the surface and subsurface of the Moon. Though photogeologic observations provide estimates for the present volumes of lunar impact basins and their ejecta deposits, there is not sufficient information to describe completely either the geometry of the basins at the time of impact or their modification with time. Determination of the structure of the crust and upper mantle beneath large basins can provide important insight into the thermal and mechanical processes associated with basin formation and modification as well as the differences in these processes as functions of basin age and size. Using observed gravity and topography together with the seismically determined crustal thickness of the central nearside, a model for the structure of the crust and upper mantle of the nearside of the Moon is presented. With this model the deep structure of the largest lunar basins are compared. The implications for the processes of basin formation and modification at different stages in lunar history are explored.

  16. Tularosa Basin Play Fairway Analysis: Partial Basin and Range Heat and Zones of Critical Stress Maps

    SciTech Connect

    Adam Brandt

    2015-11-15

    Interpolated maps of heat flow, temperature gradient, and quartz geothermometers are included as TIF files. Zones of critical stress map is also included as a TIF file. The zones are given a 5km diameter buffer. The study area is only a part of the Basin and Range, but it does includes the Tularosa Basin.

  17. Hydrocarbon systems in the East Texas basin: A basin modeling approach

    SciTech Connect

    Wescott, W.A.; Hood, W.C. )

    1993-09-01

    The East Texas basin is a prolific mature hydrocarbon province, producing oil and gas from several reservoirs and a variety of trap types. Much of the liquid hydrocarbons discovered in the basin are trapped in structures related to movement of the underlying Louann Salt. By determining the structural evolution of the basin, a framework was constructed to model the generation of hydrocarbons in the basin. Geochemical data indicate three major source horizons: the Smackover formation (Jurassic oil), shales in the Pearsal Group (Lower Cretaceous oil), and the Eagleford shale (Upper Cretaceous oil). The Jurassic source is mature throughout the basin and began to expel oil approximately 88 Ma. The distribution of Jurassic oil in Cretaceous reservoirs shows that vertical migration routes predominated. Lower Cretaceous source rocks are mature only in the deep, central part of the basin where expulsion began around 47 Ma Distribution of this oil type suggests that Lower Cretaceous source rocks occur only in localized areas of the East Texas basin. The Eagleford shale is immature in the main part of the basin, but it is mature south of the Angelina-Caldwell flexure, where is reached peak generation approximately 20 Ma. Lateral migration explains the distribution of this oil. Migration routes to the giant East Texas field may be 60 mi or more.

  18. Implication of drainage basin parameters of a tropical river basin of South India

    NASA Astrophysics Data System (ADS)

    Babu, K. J.; Sreekumar, S.; Aslam, Arish

    2016-03-01

    Drainage morphometry provides quantitative description of the drainage system which is an important aspect of the characterisation of watersheds. Chalakudi River is one of the important rivers of the South India which has attracted attention of many environmental scientists recently because of the proposed Athirapally Hydel Project across the river. SRTM (Shuttle Radar Topographic Mission) data were used for preparing DEM (Digital Elevation Model), Aspect Map and Slope Map. Geographical Information System (GIS) was used for the evaluation of linear, areal and relief aspects of morphometric parameters. The study reveals that the terrain exhibits dentritic and trellis pattern of drainage. The Chalakudi River Basin has a total area of 1,448.73 km2 and is designated as seventh-order basin. The drainage density of the basin is estimated as 2.54 and the lower-order streams mostly dominate the basin. The high basin relief indicates high runoff and sediment transport. The elongation ratio of the Chalakudi Basin is estimated as 0.48 and indicates that the shape of the basin is elongated. The development of stream segments in the basin area is more or less effected by rainfall. Relief ratio indicates that the discharge capability of watershed is very high and the groundwater potential is meagre. The low value of drainage density in spite of mountainous relief indicates that the area is covered by dense vegetation and resistant rocks permeated by fractures and joints. These studies are helpful in watershed development planning and wise utilization of natural resources.

  19. Carboniferous clastic-wedge stratigraphy, sedimentology, and foreland basin evolution: Black Warrior basin, Alabama and Mississippi

    SciTech Connect

    Hines, R.A.

    1986-05-01

    Carboniferous clastic-wedge stratigraphy and sedimentology in the Black Warrior basin of Alabama and Mississippi indicate deposition in an evolving foreland basin flanking the Appalachian-Ouachita fold-thrust belt. The strata reflect specific responses to foreland basin subsidence, orogenic activity, sediment supply, and dispersal systems. Definition of the regional stratigraphy of the clastic wedge provides for interpretation of the foreland basin subsidence history by enabling quantitative reconstruction of regional compaction and subsidence profiles. Comparison of the interpreted subsidence history with model profiles of foreland basin subsidence (predicted from loading and flexure of continental lithosphere) allows evaluation of mechanical models in terms of observed clastic-wedge sedimentology and stratigraphy. Mechanical modeling of foreland basin subsidence predicts formation of a flexural bulge that migrates cratonward ahead of the subsiding foreland basin during loading. In the Black Warrior basin, local stratigraphic thins, pinch-outs, and areas of marine-reworked sediments suggest migration of the flexural bulge. Comparison of flexural bulge migration with thermal maturation history allows evaluation of timing of stratigraphic trapping mechanisms with respect to onset of hydrocarbon generation.

  20. Precambrian shield and basement tectonics in sedimentary basin analysis

    SciTech Connect

    Touborg, J.F.

    1984-04-01

    This study focused on the use of (1) regional structural analysis of basement and Precambrian rocks surrounding a sedimentary basin, and (2) tracing basement structures into the sedimentary basin. The structural analysis of the Precambrian shield has a fundamental bearing on interpretation of overlying sedimentary cover rocks. This is expressed in the southern part of the Hudson's Bay basin and its southeastern arm, the Moose River basin. For instance, the rims of both basins are controlled by faults or graben structures. Approximately 13 major fault systems with strike lengths of 200-300 km (125-186 mi) or more can be traced from the exposed Precambrian shield into the basin in terms of lineament arrays and/or aeromagnetic and/or gravity signature. The data suggest reactivation of faults during basin sedimentation. This type of basement structural analysis in areas adjacent to sedimentary basins can provide a valuable interpretation base for subsequent seismic surveys and basin evaluation.

  1. 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.

  2. 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.

  3. A new survey of multiring impact basins on Mars

    NASA Technical Reports Server (NTRS)

    Schultz, Richard A.; Frey, Herbert V.

    1990-01-01

    Literature data on Martian multiring impact basins with diameters greater than 500 km are summarized, and evidence is found for eight new such basins. The pattern of changes of basin morphology with increasing basin size suggests three subclasses of multiring basins: (1) multiring basins with diameters up to about 1850 km, which are characterized by the Orientale type concentric structure and cumulative frequency power law slope of -0.75; (2) the Argyre-type basins (with diameters between 1850 and 3600 km, defined by rugged concentric annnuli and a power law slope of nearly -2.0; and (3) the Chryse-type basins (with diameters greater than 3600 km), which exhibit multiple concentric rings and very shallow topographic profiles. Multiring basins are found in all parts of Mars, including the northern lowlands, Tharsis, and surrounding highlands, and are associated with much of the subsequent resurfacing of cratered terrain.

  4. Propagating rift during the opening of a small oceanic basin: The Protector Basin (Scotia Arc, Antarctica)

    NASA Astrophysics Data System (ADS)

    Galindo-Zaldívar, Jesús; Bohoyo, Fernando; Maldonado, Andrés; Schreider, Anatoly; Suriñach, Emma; Vázquez, Juan Tomas

    2006-01-01

    The opening of oceanic basins constitutes one of the key features of Plate Tectonics because it determines the rifting and displacement of the continental crustal blocks. Although the mechanisms of development of large oceans are well known, the opening and evolution of small and middle size oceanic basins have not been studied in detail. The Protector Basin, located in the southern Scotia Sea, is a good example of a small oceanic basin developed between two thinned continental blocks, the Pirie Bank and the Terror Rise, poorly studied up to now. A new set of multibeam bathymetry, multichannel seismic reflection, and gravity and magnetic anomaly profiles obtained on the SCAN 2001 cruise led us to determine that the Protector Basin probably opened during the period comprised between C5Dn (17.4 Ma) and C5ACn-C5ABr chrons (13.8 Ma), forming a N-S oriented spreading axis. The end of spreading is slightly younger to the north. The start of spreading is clearly diachronous, with the most complete set of chrons up to C5Dn in the southern profile, C5Cn in the middle section and only up to C5ADn in the northern part of the basin. The spreading axis propagated northwards during the basin development, producing the wedge shape of the basin. In addition, at the NE part of the basin, a reverse fault developed in the border of the Pirie Bank after basin opening accentuates the sharp northern end. Moreover, the northwestern part of the Pirie Bank margin is an extremely stretched continental crust with N-S elongated magnetic anomalies related to incipient oceanic southward propagating spreading axes. The Protector Basin shows the oldest evidence of E-W continental stretching and subsequent oceanic spreading during Middle Miocene, related with the eastward development of the Scotia Arc that continues up to Present. The relative rotation of continental blocks during the development of small sized oceanic basins by continental block drifting favoured the opening of wedge shape basins

  5. Hydrogeology of the West Siberian Basin

    SciTech Connect

    Foley, M.G.; Bradley, D.J.; Cole, C.R.

    1996-08-01

    Nuclear fuel cycle activities of the former Soviet Union (FSU) have resulted in extensive radioactive contaminant releases to the environment in western Siberia. We are developing three-dimensional numerical models of the hydrogeology and potential contaminant migration in the West Siberian Basin. We have assumed that ground-water flow in the West Siberian Basin is topographically driven, with recharge to the basin occurring in the highlands on the west, east, and south, and internal discharge localized in numerous river valleys and lakes that ultimately discharge north to the ocean. We are modeling the regional hydrogeology as three-dimensional, steady-state, saturated flow that is recharged from above. We acquired topographic, geologic, hydrostratigraphic, hydrogeologic, and water-balance data for the West Siberian Basin and constructed a regional water table. We correlated and combined 70 different rock types derived from published descriptions of West Siberian Basin rocks into 17 rock types appropriate for assignment of hydrogeologic properties on the basis of spatial heterogeneity and constituent (i.e., sand, silt, and clay) diversity. Examination of resulting three-dimensional assemblages of rock types showed that they were consistent with published and inferred paleogeography and depositional processes. Calibrating the basin`s moisture balance (i.e., recharge and discharge) to the derived water table determined plausible input parameter values for unknowns such as hydraulic conductivities. The general directions of calculated ground-water flow suggest that major rivers act as discharge areas, with upwelling below the rivers extending down into the basement rocks, and that ground-water divides that penetrate the entire thickness of the model are evident between major rivers.

  6. 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.

  7. Basin modeling of the Parang (Socotra) Basin, northern East China Sea shelf: Implications for hydrocarbon potential

    NASA Astrophysics Data System (ADS)

    Kim, H.; Moon, S.; Lee, G.; Yoon, Y.; Kim, H.

    2013-12-01

    The hydrocarbon potential of the Parang (Socotra) Basin in the northern East China Sea shelf has remained poorly understood. We performed one-dimensional basin modeling for a dummy well located in the depocenter of the northern part of the Parang Basin to investigate the timings of hydrocarbon generation and expulsion. First, a depth-converted seismic profile crossing the dummy well was restored by backstripping and decompaction for eight regional and subregional unconformities, including the top of the acoustic basement, to reconstruct the subsidence history and to determine the timing of trap formation. The basin modeling, assuming rifting heat-flow model and source rocks with type III kerogen, suggests that the main phase of hydrocarbon (mostly gas) expulsion peaked in the Late Eocene, predating the inversion that created traps in the early Middle to latest Middle Eocene. Thus, the potential for large hydrocarbon accumulations in the northern Parang Basin is probably limited.

  8. Desert basins of the Southwest

    USGS Publications Warehouse

    Leake, Stanley A.; Konieczki, Alice D.; Rees, Julie A.H.

    2000-01-01

    Ground water is among the Nation’s most important natural resources. It provides drinking water to urban and rural communities, supports irrigation and industry, sustains the flow of streams and rivers, and maintains riparian and wetland ecosystems. In many areas of the Nation, the future sustainability of ground-water resources is at risk from overuse and contamination. Because ground-water systems typically respond slowly to human actions, a long-term perspective is needed to manage this valuable resource. This publication is one in a series of fact sheets that describe ground-water-resource issues across the United States, as well as some of the activities of the U.S. Geological Survey that provide information to help others develop, manage, and protect ground-water resources in a sustainable manner. Ground-water resources in the Southwest are among the most overused in the United States. Natural recharge to aquifers is low and pumping in many areas has resulted in lowering of water tables. The consequences of large-scale removal of water from storage are becoming increasingly evident. These consequences include land subsidence; loss of springs, streams, wetlands and associated habitat; and degradation of water quality. Water managers are now seeking better ways of managing ground-water resources while looking for supplemental sources of water. This fact sheet reviews basic information on ground water in the desert basins of the Southwest. Also described are some activities of the U.S. Geological Survey (USGS) that are providing scientific information for sustainable management of ground-water resources in the Southwest. Ground-water sustainability is defined as developing and using ground water in a way that can be maintained for an indefinite time without causing unacceptable environmental, economic, or social consequences.

  9. Basin analysis of tertiary strata in the Pattani Basin, Gulf of Thailand

    SciTech Connect

    Chonchawalit, A. ); Bustin, R.M. )

    1994-07-01

    The stratigraphic and structural evolution of the Pattani basin, the most prolific petroleum basin in Thailand, reflects the extensional tectonics of continental southeast Asia. East-west extension, a product of the northward collision of India with Eurasia since the early Tertiary resulted in the formation of a series of north-south-trending sedimentary basins including the Pattani basin. Subsidence and thermal histories of the basin can generally be accounted for by nonuniform lithospheric stretching. The validity of nonuniform lithospheric stretching as a mechanic for the formation of the Pattani basin is confirmed by a reasonably good agreement between modeled and observed vitrinite reflectance at various depths and locations. The amount of stretching and surface heat flow generally increases from the basin margin to the basin center. Crustal stretching factor ([beta]) ranges from 1.3 at the basin margin to 2.8 in the center. Subcrustal stretching factor ([sigma]) ranges from 1.3 at the margin to more than 3.0 in the center. The stretching of the lithosphere may have extended basement rocks as much as 45 to 90 km and may have caused the upwelling of asthenosphere, resulting in high heat flow. The sedimentary succession in the Pattani basin is divisible into synrift and postrift sequences. The synrift sequences comprise (1) late Eocene ( ) to early Oligocene alluvial fan, braided river, and flood-plain deposits; (2) late Oligocene to early Miocene floodplain and channel deposits; and (3) an early Miocene regressive package of marine to nonmarine sediments. Deposition of synrift sequences corresponded to rifting and extension, which included episodic block faulting and rapid subsidence. Postrift succession comprises (1) an early to middle Miocene regressive package of shallow marine to nonmarine sediments, (2) a late early Miocene transgressive package; and (3) a late Miocene to Pleistocene transgression succession.

  10. Effect of basin physical characteristics on solute fluxes in nine alpine/subalpine basins, Colorado, USA

    USGS Publications Warehouse

    Sueker, J.K.; Clow, D.W.; Ryan, J.N.; Jarrett, R.D.

    2001-01-01

    Alpine/subalpine basins may exhibit substantial variability in solute fluxes despite many apparent similarities in basin characteristics. An evaluation of controls on spatial patterns in solute fluxes may allow development of predictive tools for assessing basin sensitivity to outside perturbations such as climate change or deposition of atmospheric pollutants. Relationships between basin physical characteristics, determined from geographical information system (GIS) tools, and solute fluxes and mineral weathering rates were explored for nine alpine/subalpine basins in Rocky Mountain National Park, Colorado, using correlation analyses for 1993 and 1994 data. Stream-water nitrate fluxes were correlated positively with basin characteristics associated with the talus environment; i.e., the fractional amounts of steep slopes (??? 30??), unvegetated terrain and young debris (primarily Holocene till) in the basins, and were correlated negatively with fractional amounts of subalpine meadow terrain. Correlations with nitrate indicate the importance of the talus environment in promoting nitrate flux and the mitigating effect of areas with established vegetation, such as subalpine meadows. Total mineral weathering rates for the basins ranged from about 300 to 600 mol ha-1 year -1. Oligoclase weathering accounted for 30 to 73% of the total mineral weathering flux, and was positively correlated with the amount of old debris (primarily Pleistocene glacial till) in the basins. Although calcite is found in trace amounts in bedrock, calcite weathering accounted for up to 44% of the total mineral weathering flux. Calcite was strongly correlated with steep slope, unvegetated terrain, and young debris-probably because physical weathering in steep-gradient areas exposes fresh mineral surfaces that contain calcite for chemical weathering. Oligoclase and calcite weathering are the dominant sources of alkalinity in the basins. However, atmospherically deposited acids consume much of the

  11. Potential for deep basin-centered gas accumulation in Hanna Basin, Wyoming

    USGS Publications Warehouse

    Wilson, Michael S.; Dyman, Thaddeus S.; Nuccio, Vito F.

    2001-01-01

    The potential for a continuous-type basin-centered gas accumulation in the Hanna Basin in Carbon County, Wyoming, is evaluated using geologic and production data including mud-weight, hydrocarbon-show, formation-test, bottom-hole-temperature, and vitrinite reflectance data from 29 exploratory wells. This limited data set supports the presence of a hypothetical basin-centered gas play in the Hanna Basin. Two generalized structural cross sections illustrate our interpretations of possible abnormally pressured compartments. Data indicate that a gas-charged, overpressured interval may occur within the Cretaceous Mowry, Frontier, and Niobrara Formations at depths below 10,000 ft along the southern and western margins of the basin. Overpressuring may also occur near the basin center within the Steele Shale and lower Mesaverde Group section at depths below 18,000 to 20,000 ft. However, the deepest wells drilled to date (12,000 to 15,300 ft) have not encountered over-pressure in the basin center. This overpressured zone is likely to be relatively small (probably 20 to 25 miles in diameter) and is probably depleted of gas near major basement reverse faults and outcrops where gas may have escaped. Water may have invaded reservoirs through outcrops and fracture zones along the basin margins, creating an extensive normally pressured zone. A zone of subnormal pressure also may exist below the water-saturated, normal-pressure zone and above the central zone of overpressure. Subnormal pressures have been interpreted in the center of the Hanna Basin at depths ranging from 10,000 to 25,000 ft based on indirect evidence including lost-circulation zones. Three wells on the south side of the basin, where the top of the subnormally pressured zone is interpreted to cut across stratigraphic boundaries, tested the Niobrara Formation and recovered gas and oil shows with very low shut-in pressures.

  12. Australia`s southeastern Bonaparte basin has plenty of potential

    SciTech Connect

    Miyazaki, S.

    1997-04-21

    Situated in the Timor Sea and Joseph Bonaparte Gulf regions, the Bonaparte basin is one of the Phanerozoic basins of what is now called the North West Shelf of Australia. This basin consists of a number of Paleozoic and Mesozoic synclines and horsts. Drilling success rate for this basin is one of the highest in Australia in the last 5 years. New opportunities are available in the southeastern Bonaparte basin, where seven vacant tracts have just been released for application for exploration permits. The paper discusses the regional geology, previous exploration activities, and potentials of the southern Petrel sub-basin and Darwin shelf.

  13. A case for ancient evaporite basins on Mars

    NASA Astrophysics Data System (ADS)

    Forsythe, Randall D.; Zimbelman, James R.

    1995-03-01

    Observations indicate that a Martian analog to the Earth's salt pans and saline lakes of arid regions may have existed in crater-basins during Mars' early (Noachian) epoch. Terraced and channelized crater-basins point to ponding of surface water as well as possible prolonged and evolving base levels. In addition, supportive (evaporite basin) analogs are offered for three other morphologic features of Martian crater-basins. An evaporite basin model for crater-basins on Mars has major implications for the mechanical, chemical, and even biological processes that potentially have operated in Mars' past, and represent a spectrum of potential mineral resources. resources.

  14. 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

  15. Hydrothermal Activity in the Northern Guaymas Basin

    NASA Astrophysics Data System (ADS)

    Berndt, C.; Hensen, C.; Mortera-Gutierrez, C. A.; Sarkar, S.; Geilert, S.; Schmidt, M.; Liebetrau, V.; Kipfer, R.; Scholz, F.; Doll, M.; Muff, S.; Karstens, J.; Böttner, C.; Chi, W. C.; Moser, M.; Behrendt, R.; Fiskal, A.; Evans, T.; Planke, S.; Lizarralde, D.; Lever, M. A.

    2015-12-01

    Rift-related magmatism in the Guaymas Basin, Gulf of California induces hydrothermal activity within the basin sediments. Mobilized fluids migrate to the seafloor where they are emitted into the water column changing ocean chemistry and fuelling chemosynthetic ecosystems. New seismic and geochemical data from the northern rift arm of the Guaymas Basin document the variety of fluid expulsion phenomena from large-scale subsurface sediment mobilization related to contact metamorphosis to focused small-scale structures. The geochemical composition of emitted fluids depends largely on the age of the fluid escape structures with respect to the underlying intrusions. Whereas, old structures are dominated by methane emission, young vent sites are characterized by hot fluids that carry a wide range of minerals in solution. The overall high geothermal gradient within the basin (mainly between 160 and 260 °C/km) leads to a thin gas hydrate stability zone. Thus, deep hydrothermal fluid advection affects the gas hydrate system and makes it more dynamic than in colder sedimentary basins.

  16. Satellite altimetry over large hydrological basins

    NASA Astrophysics Data System (ADS)

    Calmant, Stephane

    2015-04-01

    The use of satellite altimetry for hydrological applications, either it is basin management or hydrological modeling really started with the 21st century. Before, during two decades, the efforts were concentrated on the data processing until a precision of a few decimeters could be achieved. Today, several web sites distribute hundreds of series spread over hundeds of rivers runing in the major basins of the world. Among these, the Amazon basin has been the most widely studied. Satellite altimetry is now routinely used in this transboundary basin to predict discharges ranging over 4 orders of magnitude. In a few years, satellite altimetry should evolve dramatically. This year, we should see the launchs of Jason-3 and that of Sentinel-3A operating in SAR mode. With SAR, the accuracy and resolution of a growing number of measurements should be improved. In 2020, SWOT will provide a full coverage that will join in a unique framework all the previous and forthcoming missions. These technical and thematical evolutions will be illustrated by examples taken in the Amazon and Congo basin.

  17. Maturation modeling in Otway Basin, Australia

    SciTech Connect

    Middleton, M.F.; Falvey, D.A.

    1983-02-01

    The Otway basin is a Jurassic to Pliocene sedimentary basin formed on the southern Australian continental margin. Its formation is associated with rifting and breakup of the Australian and Antarctic plates. Lithospheric cooling and contraction have probably produced post-breakup subsidence. Either lithospheric stretching or deep crustal metamorphism may have produced pre-breakup subsidence. These mechanisms have identifiable thermal histories. Organic diagenesis (specifically the reflectance of vitrinite in oil) is empirically determined by the thermal and depositional history of an organic sediment. Thus, the stages of hydrocarbon maturity of Otway basin sediments can be modeled. Depositional history is determined from ''geohistory analysis'' and thermal history depends on the subsidence mechanism applied to the basin. A paleo-heat-flow history derived from the deep crustal metamorphism model of subsidence produces a maturation profile with depth that is consistent with observed vitrinite reflectance data, although organic diagenesis modeling is relatively insensitive to precise details of thermal history. Depositional and maturation history modeling for the present day, 20 Ma ago, 40 Ma ago, and 60 Ma ago is applied to a seismic profile across the southern Australian continental shelf in the Otway basin as a demonstration of the projection backward in time of sedimentation and organic diagenesis.

  18. A geological history of the Turkana Basin.

    PubMed

    Feibel, Craig S

    2011-01-01

    The Turkana Basin preserves a long and detailed record of biotic evolution, cultural development, and rift valley geology in its sedimentary strata. Before the formation of the modern basin, Cretaceous fluvial systems, Paleogene lakes, and Oligo-Miocene volcano-sedimentary sequences left fossil-bearing strata in the region. These deposits were in part related to an early system of rift basins that stretched from Sudan to the Indian Ocean. The present-day basin has its origins in Pliocene tectonic developments of the modern rift, with subsidence making room for more than one kilometer of Plio-Pleistocene strata. Much of this sequence belongs to the Omo Group, richly fossiliferous sediments associated with the ancestral Omo River and its tributaries. Modern Lake Turkana has a record stretching back more than 200 thousand years, with earlier lake phases throughout the Plio-Pleistocene. The geologic history of the basin is one of dynamic landscapes responding to environmental influences, including tectonics, volcanic activity and climate. PMID:22170690

  19. Petroleum geochemistry of the Zala basin, Hungary

    SciTech Connect

    Clayton, J.L. ); Koncz, I. )

    1994-01-01

    The Zala basin is a subbasin within the Pannonian basis on Hungary. Oil and smaller amounts of gas are produced from Upper Triassic through Miocene reservoirs. Our geochemical study of oils and rocks in the basin indicate that two, and possibly three, genetic oil types are present in the basin. Miocene source rocks, previously believed by explorationists to be the predominant source rock, have expelled minor amounts of hydrocarbons. The main source rock is the Upper Triassic (Rhaetian) Koessen Marl Formation or its stratigraphic equivalent. Oils derived from the Triassic source rock are recognizable by their isotopic and biological marker composition, and high content of metals. In other areas of Europe, Upper Triassic source rocks have been correlated with large oil accumulations (e.g., Molassa and Villafortuna fields, Po basin, and other fields in Italy) or are postulated to be good potential source rocks (e.g., Bristol channel Trough). Knowledge of the geochemical characteristics of oils derived from these Upper Triassic source rocks and understanding of the source rock distribution and maturation history are important for recognizing Triassic oil-source bed relationships and for further exploration in other basins in Hungary and other parts of Europe where Triassic source rocks are present.

  20. Offshore Essaouira basin: Geology and hydrocarbon potential

    SciTech Connect

    Jabour, H.; Ait Salem, A. )

    1991-03-01

    The study area lies in the offshore extension of the onshore Essaouria basin. The Mesozoic development of the Essaouira margin was largely controlled by Late Triassic to Mid-Jurassic rifting and subsequent opening of the Central Atlantic, with the evolution of a typical passive, opening of the Central Atlantic, with the evolution of a typical passive, continental margin. Diapiric salt structure recognized on seismic defines a Late Triassic-Early Jurassic salt basin in the offshore area initiated during early rifting. Subsidence and sea-level rise during Jurassic resulted in carbonate platform development. This was followed during Cretaceous and Tertiary time by the deposition of a prograding siliciclastic system. Only three wells have been drilled in this basin. Although drilled on poorly defined prospects, these wells encountered gas and oil shows. Fairly extensive seismic coverage of good quality data is now available. A study based on an integrated approach involving seismic facies definition and mapping, correlation with well data, identification of the principal control on sedimentation, and basin modeling in conjunction with source rock prediction and maturity modeling has been carried out. Results have shown that hydrocarbon potential in the offshore Essaouira basin has not yet been substantiated by drilling. Attractive structural and stratigraphic prospects exist in the shelf, shelf edge, and the slope, and await confirmation by drilling.

  1. A geological history of the Turkana Basin.

    PubMed

    Feibel, Craig S

    2011-01-01

    The Turkana Basin preserves a long and detailed record of biotic evolution, cultural development, and rift valley geology in its sedimentary strata. Before the formation of the modern basin, Cretaceous fluvial systems, Paleogene lakes, and Oligo-Miocene volcano-sedimentary sequences left fossil-bearing strata in the region. These deposits were in part related to an early system of rift basins that stretched from Sudan to the Indian Ocean. The present-day basin has its origins in Pliocene tectonic developments of the modern rift, with subsidence making room for more than one kilometer of Plio-Pleistocene strata. Much of this sequence belongs to the Omo Group, richly fossiliferous sediments associated with the ancestral Omo River and its tributaries. Modern Lake Turkana has a record stretching back more than 200 thousand years, with earlier lake phases throughout the Plio-Pleistocene. The geologic history of the basin is one of dynamic landscapes responding to environmental influences, including tectonics, volcanic activity and climate.

  2. Stilling Basin Performance Analysis by ADV

    NASA Astrophysics Data System (ADS)

    Aleyasin, Sobhan; Fathi, Nima; Vorobieff, Peter

    2014-11-01

    The outlet flow from dams, channels, and pipes, as well as the river flow, can cause damage to the bed of the river or channel and cause scouring of structures such as the saddles of bridges, because of the huge amount of the kinetic energy carried by the flow. One of the ways to dissipate this energy is via the use of stilling basins, which are structures that calm the flow. Here we present a study of one type of stilling basins for pipe outlets based on a widely used standard. During the study, splitters and cellular baffles were placed in the stilling basin, and their locations were changed to assess their effect on the flow dissipation. Velocity at several locations in the basin was measured via acoustic Doppler velocimetry (ADV) for different Froude numbers to investigate the effect of flow rate and inlet velocity. Based on the findings of the experiments, we make several suggestions regarding the efficiency and geometry of stilling basins.

  3. Surficial deposits in the Bear Lake Basin

    USGS Publications Warehouse

    Reheis, Marith C.; Laabs, Benjamin J.C.; Forester, Richard M.; McGeehin, John P.; Kaufman, Darrell S.; Bright, Jordon

    2005-01-01

    Mapping and dating of surficial deposits in the Bear Lake drainage basin were undertaken to provide a geologic context for interpretation of cores taken from deposits beneath Bear Lake, which sometimes receives water and sediment from the glaciated Bear River and sometimes only from the small drainage basin of Bear Lake itself. Analyses of core sediments by others are directed at (1) constructing a high-resolution climate record for the Bear Lake area during the late Pleistocene and Holocene, and (2) investigating the sources and weathering history of sediments in the drainage basin. Surficial deposits in the upper Bear River and Bear Lake drainage basins are different in their overall compositions, although they do overlap. In the upper Bear River drainage, Quaternary deposits derived from glaciation of the Uinta Range contain abundant detritus weathered from Precambrian quartzite, whereas unglaciated tributaries downstream mainly contribute finer sediment weathered from much younger, more friable sedimentary rocks. In contrast, carbonate rocks capped by a carapace of Tertiary sediments dominate the Bear Lake drainage basin.

  4. The advertisement and aggressive calls of Rhinella abei (Baldissera, Caramaschi, and Haddad, 2004) (Anura: Bufonidae) from Campo Largo, Paraná, Brazil.

    PubMed

    Batista, Vinicius Guerra; Ramalho, Werther Pereira; Amaral, Diogo Ferreira Do; Maciel, Natan Medeiros; Bastos, Rogério Pereira

    2016-01-01

    Rhinella abei is a medium-sized species (snout-to-vent length 57.0-76.4 mm in males; 60.4-83.9 mm in females-Baldissera et al. 2004) of the Rhinella crucifer species group, distributed in the Brazilian Atlantic Rainforest, from the State of Paraná to northern Rio Grande do Sul (Frost 2016). It is recorded in forested areas (Conte & Rossa-Feres 2007), or while breeding along forest edges and open habitats. Information on advertisement calls of species in the R. crucifer group is available for R. casconi, R. crucifer, R. inopina and R. ornata (Andrade et al. 2015; Heyer et al. 1990; Oliveira et al. 2014; Roberto et al. 2014). Here we describe the advertisement and aggressive calls of R. abei recorded in the municipality of Campo Largo (25.507472° S, 49.376632° W, datum "WGS84"), southeast State of Paraná, Brazil. PMID:27394842

  5. Levelling profiles and a GPS network to monitor the active folding and faulting deformation in the Campo de Dalias (Betic Cordillera, southeastern Spain).

    PubMed

    Marín-Lechado, Carlos; Galindo-Zaldívar, Jesús; Gil, Antonio José; Borque, María Jesús; de Lacy, María Clara; Pedrera, Antonio; López-Garrido, Angel Carlos; Alfaro, Pedro; García-Tortosa, Francisco; Ramos, Maria Isabel; Rodríguez-Caderot, Gracia; Rodríguez-Fernández, José; Ruiz-Constán, Ana; de Galdeano-Equiza, Carlos Sanz

    2010-01-01

    The Campo de Dalias is an area with relevant seismicity associated to the active tectonic deformations of the southern boundary of the Betic Cordillera. A non-permanent GPS network was installed to monitor, for the first time, the fault- and fold-related activity. In addition, two high precision levelling profiles were measured twice over a one-year period across the Balanegra Fault, one of the most active faults recognized in the area. The absence of significant movement of the main fault surface suggests seismogenic behaviour. The possible recurrence interval may be between 100 and 300 y. The repetitive GPS and high precision levelling monitoring of the fault surface during a long time period may help us to determine future fault behaviour with regard to the existence (or not) of a creep component, the accumulation of elastic deformation before faulting, and implications of the fold-fault relationship. PMID:22319309

  6. Levelling Profiles and a GPS Network to Monitor the Active Folding and Faulting Deformation in the Campo de Dalias (Betic Cordillera, Southeastern Spain)

    PubMed Central

    Marín-Lechado, Carlos; Galindo-Zaldívar, Jesús; Gil, Antonio José; Borque, María Jesús; de Lacy, María Clara; Pedrera, Antonio; López-Garrido, Angel Carlos; Alfaro, Pedro; García-Tortosa, Francisco; Ramos, Maria Isabel; Rodríguez-Caderot, Gracia; Rodríguez-Fernández, José; Ruiz-Constán, Ana; de Galdeano-Equiza, Carlos Sanz

    2010-01-01

    The Campo de Dalias is an area with relevant seismicity associated to the active tectonic deformations of the southern boundary of the Betic Cordillera. A non-permanent GPS network was installed to monitor, for the first time, the fault- and fold-related activity. In addition, two high precision levelling profiles were measured twice over a one-year period across the Balanegra Fault, one of the most active faults recognized in the area. The absence of significant movement of the main fault surface suggests seismogenic behaviour. The possible recurrence interval may be between 100 and 300 y. The repetitive GPS and high precision levelling monitoring of the fault surface during a long time period may help us to determine future fault behaviour with regard to the existence (or not) of a creep component, the accumulation of elastic deformation before faulting, and implications of the fold-fault relationship. PMID:22319309

  7. Tectonics and Quaternary sequence development of basins along the active Vienna Basin strike-slip fault

    NASA Astrophysics Data System (ADS)

    Salcher, B.; Lomax, J.; Meurers, B.; Smit, J.; Preusser, F.; Decker, K.

    2012-04-01

    The Vienna Basin strike-slip fault is a continent scale active fault extending over a distance of some 300 km from the Eastern Alps through the Vienna Basin into the Western Carpathians. Sinistral movement causes the formation of several tight Pleistocene strike-slip basins within the older Miocene Vienna Basin. These sub-basins not only have a high relevance for groundwater exploitation but their fault activities depict serious seismic hazards. Basins are filled with fluvial sediments from the Danube and, closer to the Alpine front, with thick alluvial fan deposits. However, knowledge on the stratigraphy and tectonics is sparse and rather limited to the Miocene part of the Vienna Basin as it hosts giant hydrocarbon fields. This study tackles two major questions: (i) What is the effect of Quaternary climatic oscillations and subsidence on the sequence development of the alluvial fans and (ii) what is the deformation style of these basins? To answer (i) we present a series of new OSL ages and biotic data from both, surface and cores, to better constrain the timing of fan activity, fan abandonment but also to constrain the onset of Pleistocene basin formation. For (ii) we utilize information from unparalleled geophysical and geological data. Specifically we utilize industrial Bouguer gravity's derivatives to highlight shallow structures and to compensate for the lag of fault trace information. The integration of geological and geophysical data highlights textbook-like models of strike-slip basins, with typical features like Riedel shears with intervening relay ramps, en-echelon sidewall faults and a cross-basin fault zone delimiting opposite depocenters. The infill reflects a distinct cyclicity with thick sequences of coarse sediments deposited during colder periods and thin sequences of paleosol and flood sediments deposited during warmer periods. Ages indicate main activity around the short peak glacial periods and basin formation starting c. 300 ka ago. The

  8. Exploration in the Ombilin Intermontane Basin, West Sumatra

    SciTech Connect

    Koning, T. Petroleum Co., Lagos )

    1996-01-01

    The Ombilin Basin is a Tertiary intermontane basin located within the Barisan Mountain Range of Sumatra. Oil exploration commenced in the Ombilin Basin in the early 1980s when geological mapping was carried out, a synthetic aperture radar survey was flown, and a basin-wide geophysical survey was completed. This effort led to the drilling of Sinimar No. 1 to a total depth 3020 m. Sinimar No. 1 was a historic well in Indonesia's oil industry since it was the first oil exploration well drilled in the Ombilin Basin and also the first well drilled in an intermontane basin in Indonesia. Oil, gas and condensate was tested in the well. An integrated interpretation of the well, geophysical and outcrop data indicates that despite its small areal size (30 km x 50 km), the Ombilin Basin is a deep pull-apart basin containing up to 4500 m of Tertiary sediments, ranging in age from Middle Eocene to Early Miocene. The basin currently is in an intermontane basin structural setting but it was also an intermontane basin during its Early Tertiary depositional history. During the Eocene, alluvial fans and massive debris flows were deposited on the basin margins and a large lake occupied the basin center. Fluvial deposition occurred in the basin during the Oligocene followed by deposition of marine shales, sandstones, and isolated reefs during the Miocene. Although the Ombilin Basin is located within Sumatra's magmatic arc and is partially covered by volcanics from extinct and active volcanoes, the subsurface temperature gradients of 1.62 deg. F/100 ft. recorded in Sinimar No. I and 1.47 deg F/100 ft. measured in a deep (670 m) coal exploration core hole are significantly cooler than the average subsurface temperature gradients in the Sumatra back-arc basins. Organic-rich Eocene lacustrine shales are the likely source rocks for the hydrocarbons tested in Sinimar No. 1 and the oil seeps located along the basin margins.

  9. Exploration in the Ombilin Intermontane Basin, West Sumatra

    SciTech Connect

    Koning, T.

    1996-12-31

    The Ombilin Basin is a Tertiary intermontane basin located within the Barisan Mountain Range of Sumatra. Oil exploration commenced in the Ombilin Basin in the early 1980s when geological mapping was carried out, a synthetic aperture radar survey was flown, and a basin-wide geophysical survey was completed. This effort led to the drilling of Sinimar No. 1 to a total depth 3020 m. Sinimar No. 1 was a historic well in Indonesia`s oil industry since it was the first oil exploration well drilled in the Ombilin Basin and also the first well drilled in an intermontane basin in Indonesia. Oil, gas and condensate was tested in the well. An integrated interpretation of the well, geophysical and outcrop data indicates that despite its small areal size (30 km x 50 km), the Ombilin Basin is a deep pull-apart basin containing up to 4500 m of Tertiary sediments, ranging in age from Middle Eocene to Early Miocene. The basin currently is in an intermontane basin structural setting but it was also an intermontane basin during its Early Tertiary depositional history. During the Eocene, alluvial fans and massive debris flows were deposited on the basin margins and a large lake occupied the basin center. Fluvial deposition occurred in the basin during the Oligocene followed by deposition of marine shales, sandstones, and isolated reefs during the Miocene. Although the Ombilin Basin is located within Sumatra`s magmatic arc and is partially covered by volcanics from extinct and active volcanoes, the subsurface temperature gradients of 1.62 deg. F/100 ft. recorded in Sinimar No. I and 1.47 deg F/100 ft. measured in a deep (670 m) coal exploration core hole are significantly cooler than the average subsurface temperature gradients in the Sumatra back-arc basins. Organic-rich Eocene lacustrine shales are the likely source rocks for the hydrocarbons tested in Sinimar No. 1 and the oil seeps located along the basin margins.

  10. Miocene tephrochronology in the northern Basin and Range

    SciTech Connect

    Perkins, M.E.; Brown, F.H.; Nash, W.P. . Dept. of Geology and Geophysics)

    1993-04-01

    Silicic air-fall tephra layers with unaltered glass shards preserved in Miocene basins of the northern Basin and Range Province (NBR) were sampled from well-exposed sections in the Goose Creek (GCB) and Ibapah (IB) basins in the northeastern NBR, and the El Pasco basin (EPB) in the southwestern NBR. Each basin may contain up to 50 tephras. Glass shards from individual tephras in any one basin are compositionally distinct, as shown by XRF and electron microprobe analysis. Seventeen tephra correlate between two or more basins; 12 of these are regionally important, providing precise stratigraphic ties across the NbR. Four regionally correlative tephras are white biotitic ashes from southern Nevada sources, whereas eight are gray vitric ashes from Yellowstone hot spot sources. Dates on tephra layers and lava flows in the basins, and on ashflow units correlated with four other tephra provide a preliminary chronology for the tephra in the all basins. In each section [Delta]h/[Delta]t appears constant on time scales [>=]1 Ma, but variation in [Delta]h/[Delta]t is demonstrated from IB, and is likely typical of all basins. Sedimentation in all five basins begins in the time interval of 14.5--12.5 Ma, which may represent the beginning of a phase of regional extension in the NBR. Post-[approximately]9.5 Ma deformation has affected all basins and likely contributed to the termination of sedimentation in the exposed areas of these basins.

  11. Modified Streamflows 1990 Level of Irrigation : Missouri, Colorado, Peace and Slave River Basin, 1928-1989.

    SciTech Connect

    A.G. Crook Company; United States. Bonneville Power Administration

    1993-07-01

    This report presents data for monthly mean streamflows adjusted for storage change, evaporation, and irrigation, for the years 1928-1990, for the Colorado River Basin, the Missouri River Basin, the Peace River Basin, and the Slave River Basin.

  12. Independent focuses Philippines exploration on Visayan basin

    SciTech Connect

    Rillera, F.G.

    1995-08-21

    Cophil Exploration Corp., a Filipino public company, spearheaded 1995 Philippine oil and gas exploration activity with the start of its gas delineation drilling operations in Libertad, northern Cebu. Cophil and its Australian partners, Coplex Resources NL and PacRim Energy NL, have set out to complete a seven well onshore drilling program within this block this year. The companies are testing two modest shallow gas plays, Libertad and Dalingding, and a small oil play, Maya, all in northern Cebu about 500 km southeast of Manila. Following a short discussion on the geology and exploration history of the Visayan basin, this article briefly summarizes Cophil`s ongoing Cebu onshore drilling program. Afterwards, discussion focuses on identified exploration opportunities in the basin`s offshore sector.

  13. Radial thickness variations of Orientale basin ejecta

    NASA Technical Reports Server (NTRS)

    Cordell, B. M.

    1978-01-01

    Moore et al. (1974) measure the thickness of Orientale basin ejecta on the basis of filling of individual prebasin craters and a depth-diameter relation for fresh lunar craters. In the reported investigation the concept of filling of preexisting craters with basin ejecta is utilized somewhat differently to ascertain Orientale basin ejecta thicknesses and volume from the Cordillera ring with a radius of 450 km out to almost 2 radii. Briefly, the approach is to assume a reasonable geometric model for the form of Orientale ejecta, calculate how many pre-Orientale craters would be destroyed by the deposition of the ejecta, and match the model to Orientale crater statistics. The results of the investigation show that a radial ejecta thickness function can be derived from crater statistics.

  14. Hydrocarbon maturation in Laramide basins - constraints from evolution of northern Big Horn basin, Wyoming and Montana

    SciTech Connect

    Hagen, E.S.; Furlong, K.P.; Surdam, R.C.

    1984-04-01

    Thermal and mechanical models were used to quantify the effects of Laramide uplifts and subsequent synorogenic deposition on the hydrocarbon maturation of Cretaceous source rocks in the Big Horn basin. Laramide deformation and resultant sedimentation has clearly affected hydrocarbon maturation of Cretaceous source rocks. (Thermopolis, Mowry, Frontier, Cody). Modified Lopatin-type reconstructions suggest that a significant region containing Cretaceous source rocks has been within the liquid hydrocarbon window. The earliest onset of hydrocarbon maturation in the northern Big Horn basin was latest Eocene, with some regions still containing immature Cretaceous source rocks as a consequence of Cenozoic erosion, uplift of the Pryor Mountains, and lack of burial. Regional geologic features indicate that the basin formed as a result of flexural compensation of an elastic lithosphere during emplacement of the Beartooth and Pryor Mountains, and possibly the Absaroka volcanics. This was determined by 2-dimensional models which predict sediment thickness caused by tectonic loading and subsequent sedimentation. Flexural rigidities of 10/sup 2/2exclamation-10/sup 22/ newton-meters adequately explain flexural subsidence in the northern Big Horn basin. The present basin configuration also was compared with a theoretical profile based on geologic constraints. Subsidence models for the present basin profile suggest the Paleocene thrusting of the Beartooth block contributes a majority of the tectonic loading and that Cenozoic erosion has drastically affected the resultant sedimentary sequence (Fort Union and Wasatch). These models, along with stratigraphic reconstructions, can be combined to pinpoint areas of potential hydrocarbon maturation within Laramide-type basins.

  15. Avian cholera in Nebraska's Rainwater Basin

    USGS Publications Warehouse

    Windingstad, R.M.; Hurt, J.J.; Trout, A.K.; Cary, J.

    1984-01-01

    The first report of avian cholera in North America occurred in northwestern Texas in winter 1944 (Quortrup et al. 1946). In 1975, mortality from avian cholera occurred for the first time in waterfowl in the Rainwater Basin of Nebraska when an estimated 25,000 birds died (Zinkl et al. 1977). Avian cholera has continued to cause mortality in wild birds in specific areas of the Basin each spring since. Losses of waterfowl from avian cholera continue to be much greater in some of the wetlands in the western part of the Basin than in the east. Several wetlands in the west have consistently higher mortality and are most often the wetlands where initial mortality is noticed each spring (Figure 1). The establishment of this disease in Nebraska is of considerable concern because of the importance of the Rainwater Basin as a spring staging area for waterfowl migrating to their breeding grounds. The wetlands in this area are on a major migration route used by an estimated 5 to 9 million ducks and several hundred thousand geese. A large portion of the western mid-continental greater white-fronted goose (Anser albifrons) population stage in the Basin each spring. Occasionally, whooping cranes (Grus americana) use these wetlands during migration, and lesser sandhill cranes (Grus canadensis) staging on the nearby Platte River sometimes use wetlands where avian cholera occurs (Anonymous 1981). Our objectives were to determine whether certain water quality variables in the Rainwater Basin differed between areas of high and low avian cholera incidence. These results would then be used for laboratory studies involving the survivability of Pasteurella multocida, the causative bacterium of avian cholera. Those studies will be reported elsewhere.

  16. The "normal" elongation of river basins

    NASA Astrophysics Data System (ADS)

    Castelltort, Sebastien

    2013-04-01

    The spacing between major transverse rivers at the front of Earth's linear mountain belts consistently scales with about half of the mountain half-width [1], despite strong differences in climate and rock uplift rates. Like other empirical measures describing drainage network geometry this result seems to indicate that the form of river basins, among other properties of landscapes, is invariant. Paradoxically, in many current landscape evolution models, the patterns of drainage network organization, as seen for example in drainage density and channel spacing, seem to depend on both climate [2-4] and tectonics [5]. Hovius' observation [1] is one of several unexplained "laws" in geomorphology that still sheds mystery on how water, and rivers in particular, shape the Earth's landscapes. This narrow range of drainage network shapes found in the Earth's orogens is classicaly regarded as an optimal catchment geometry that embodies a "most probable state" in the uplift-erosion system of a linear mountain belt. River basins currently having an aspect away from this geometry are usually considered unstable and expected to re-equilibrate over geological time-scales. Here I show that the Length/Width~2 aspect ratio of drainage basins in linear mountain belts is the natural expectation of sampling a uniform or normal distribution of basin shapes, and bears no information on the geomorphic processes responsible for landscape development. This finding also applies to Hack's [6] law of river basins areas and lengths, a close parent of Hovius' law. [1]Hovius, N. Basin Res. 8, 29-44 (1996) [2]Simpson, G. & Schlunegger, F. J. Geophys. Res. 108, 2300 (2003) [3]Tucker, G. & Bras, R. Water Resour. Res. 34, 2751-2764 (1998) [4]Tucker, G. & Slingerland, R. Water Resour. Res. 33, 2031-2047 (1997) [5]Tucker, G. E. & Whipple, K. X. J. Geophys. Res. 107, 1-1 (2002) [6]Hack, J. US Geol. Surv. Prof. Pap. 294-B (1957)

  17. Paleohydrogeology of the San Joaquin basin, California

    USGS Publications Warehouse

    Wilson, A.M.; Garven, G.; Boles, J.R.

    1999-01-01

    Mass transport can have a significant effect on chemical diagenetic processes in sedimentary basins. This paper presents results from the first part of a study that was designed to explore the role of an evolving hydrodynamic system in driving mass transport and chemical diagenesis, using the San Joaquin basin of California as a field area. We use coupled hydrogeologic models to establish the paleohydrogeology, thermal history, and behavior of nonreactive solutes in the basin. These models rely on extensive geological information and account for variable-density fluid flow, heat transport, solute transport, tectonic uplift, sediment compaction, and clay dehydration. In our numerical simulations, tectonic uplift and ocean regression led to large-scale changes in fluid flow and composition by strengthening topography-driven fluid flow and allowing deep influx of fresh ground water in the San Joaquin basin. Sediment compaction due to rapid deposition created moderate overpressures, leading to upward flow from depth. The unusual distribution of salinity in the basin reflects influx of fresh ground water to depths of as much as 2 km and dilution of saline fluids by dehydration reactions at depths greater than ???2.5 km. Simulations projecting the future salinity of the basin show marine salinities persisting for more than 10 m.y. after ocean regression. Results also show a change from topography-to compaction-driven flow in the Stevens Sandstone at ca. 5 Ma that coincides with an observed change in the diagenetic sequence. Results of this investigation provide a framework for future hydrologic research exploring the link between fluid flow and diagenesis.

  18. Atlantic Mesozoic marginal basins: an Iberian view

    SciTech Connect

    Wilson, R.C.L.

    1987-05-01

    In the light of theoretical models for crustal stretching that precedes ocean opening, it is unlikely that Iberian basins have mirror image counterparts beneath North American or other European continental shelves. However, certain Iberian sedimentary sequences are comparable to those found in other basins. Of particular note are (1) the almost identical pre-rift sequences in all these areas, (2) the development of Upper Jurassic carbonate buildups in Portugal, Morocco, and beneath the Scotian Shelf, and (3) the hydrocarbon-bearing Upper Jurassic and Lower Cretaceous synrift and postrift siliciclastics of North America, Iberia, and Aquitaine. In the prerift sequences, Triassic red beds are capped by evaporites, which subsequently influenced the structural development of basins. Intertidal and supratidal carbonates occur at the base of the Jurassic and are overlain by Lower and Middle Jurassic limestone-shale sequences, which in places contain bituminous shales. In Portugal only, resedimented carbonates of Toarcian-Aalenian age are associated with an uplifted basement horst. In Portugal, Aquitaine, and eastern Canada, Middle Jurassic high-energy carbonate platforms developed. Synrift siliciclastic sequences show spectacular evidence for deposition within fault-bounded basins. In Portugal, lower Kimmeridgian clastics are up to 3 km thick, but Upper-Lower Cretaceous sequences are relatively thin (ca. 1 km), in contrast to those of the Basco-Cantabrian region where they exceed 10 km. In the latter region occurs the fluvially dominated Wealden (Upper Jurassic-Neocomian) and Urgonian carbonate platforms and associated basinal sediments. In the Asturias basin, Kimmeridgian shales and fluvially dominated deltaic sandstones succeed conglomeratic fluvial sandstones of uncertain age.

  19. 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.

  20. Geothermal structure of Australia's east coast basins

    NASA Astrophysics Data System (ADS)

    Danis, C. R.; O'Neill, C.

    2010-12-01

    The east coast sedimentary basins of Australia formed on an active margin of eastern Gondwana, and constitute an important hydrocarbon resource. The 1600km long Sydney-Gunnedah-Bowen Basin (SGBB) is largest east coast basin system, with thick Permian to Jurassic sedimentary successions overlying Palaeozoic basement rocks. The SGBB has been the focus of renewed geothermal exploration interest, however, the thermal state and geothermal potential of the system is largely unconstrained. Geothermal exploration programs require an accurate estimate of subsurface temperature information, in addition to favourable geology, to make informed decisions on potential targe developments. Primarily temperature information comes from downhole measurements, generally non-equilibrated, which are traditionally extrapolated to depth, however such extrapolation does not take into account variations in geological structure or thermal conductivity. Here we import deep 3D geological models into finite element conduction simulations, using the code Underworld, to calculate the deep thermal structure of the basin system. Underworld allows us to incorporate complex, detailed geological architecture models, incorporating different material properties for different layers, with variable temperature and depth-dependent properties. We adopt a fixed top boundary temperature on a variable topographic surface, and vary the bottom surface boundary condition, to converge of models which satisfy equilibrated downhole temperature measurement constraints. We find coal plays an important role in insulating sedimentary basins. Heat refracts around the coal interval and produces elevated temperatures beneath thick sediments, especially where thick coal intervals are present. This workflow has been formalized into an Underworld geothermal model library, enabling model centric computational workflows. Using the imported model architecture from the geology, data can be continuously updated and added to the

  1. 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.

  2. Paleohydrogeology of the San Joaquin basin, California

    SciTech Connect

    Wilson, A.M.; Garven, G.; Boles, J.R.

    1999-03-01

    Mass transport can have a significant effect on chemical diagenetic processes in sedimentary basins. This paper presents results from the first part of a study that was designed to explore the role of an evolving hydrodynamic system in driving mass transport and chemical diagenesis, using the San Joaquin basin of California as a field area. The authors use coupled hydrogeologic models to establish the paleohydrogeology, thermal history, and behavior of nonreactive solutes in the basin. These models rely on extensive geological information and account for variable-density fluid flow, heat transport, solute transport, tectonic uplift, sediment compaction, and clay dehydration. In the numerical simulations, tectonic uplift and ocean regression led to large-scale changes in fluid flow and composition by strengthening topography-driven fluid flow and allowing deep influx of fresh ground water in the San Joaquin basin. Sediment compaction due to rapid deposition created moderate overpressures, leading to upward flow from depth. The unusual distribution of salinity in the basin reflects influx of fresh ground water to depths of as much as 2 km and dilution of saline fluids by dehydration reactions at depths greater than {approximately}2.5 km. Simulations projecting the future salinity of the basin show marine salinities persisting for more than 10 m.y. after ocean regression. Results also show a change from topography- to compaction-driven flow in the Stevens Sandstone at ca. 5 Ma that coincides with an observed change in the diagenetic sequence. Results of this investigation provide a framework for future hydrologic research exploring the link between fluid flow and diagenesis.

  3. Modelling depositional shifts between sedimentary basins: Sediment pathways in Paratethys basins during the Messinian Salinity Crisis

    NASA Astrophysics Data System (ADS)

    Bartol, J.; Matenco, L.; Garcia-Castellanos, D.; Leever, K.

    2012-04-01

    The evolution of sedimentary basins separated by uplifted topographic barriers is characterised by gradual regressive deposition until one of the basins is filled and its sedimentation bypasses to the adjacent basin, defining a depositional shift. One of the critical parameters controlling these depositional shifts is sea level variation, its drop potentially triggering a depositional shift by cancelling the available accommodation space. Conversely, a sea level rise can create new accommodation space resulting in a depositional shift towards a previously overfilled basin. Here we use a three dimensional numerical model to study the sedimentary response to sea level variations of a system of two basins. In this model, a single mountainous source area is feeding an intra-continental basin that is separated by a submarine barrier from another basin with normal marine bathymetry. The sedimentary response is modelled during a cycle of sea-level drop and subsequent rebound that exposes the barrier to sub-aerial erosion. The examined parameters are the barrier height, magnitude and duration of sea level change, climate and flexural rigidity. Modelling demonstrates that shifting the bulk of sedimentation from the continental basin to the open marine environment requires some minimum magnitudes and durations of sea level drop. Moreover, given the specific geometry and parameters of our model, an intervening barrier causes a delay of up to 0.35 Myr, depending on the magnitude and duration of sea level change, to the onset of an outward depositional shift when compared to a situation without a barrier. These depositional shifts depend on changes in climate, magnitude and duration of sea level change. Model results are applied to the connectivity between the Black Sea and the Dacic Basin, suggesting that depositional shifts observed during the Messinian Salinity Crisis can be explained by a sea level drop of > 1000 m in the Black Sea.

  4. 14. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM TOWARD SETTLING BASIN, ...

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

    14. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM TOWARD SETTLING BASIN, SHOWING RIGHT FORK TO BYPASS, LEFT FORK TO BASIN - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  5. 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

  6. View west of reserve basin of submarine trout and frigate ...

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

    View west of reserve basin of submarine trout and frigate Edward E. McDonnell - Naval Base Philadelphia-Philadelphia Naval Shipyard, Reserve Basin & Marine Railway, League Island, Philadelphia, Philadelphia County, PA

  7. Hazard categorization of 105-KE basin debris removal project

    SciTech Connect

    Meichle, R.H.

    1996-01-25

    This supporting document provides the hazard categorization for 105-KE Basin Debris Removal Project activities planned in the K east Basin. All activities are categorized as less than Hazard Category 3.

  8. Grande Ronde Basin Fish Habitat Enhancement Project : 1998 Annual Report.

    SciTech Connect

    McGowan, Vance R.; Powell, Russ M.

    1999-05-01

    The primary goal of ''The Grande Ronde Basin Fish Habitat Improvement Project'' is to access, create, improve, protect, and restore reparian and instream habitat for anadromous salmonids, thereby maximizing opportunities for natural fish production within the basin.

  9. Geology of the Caloris basin, Mercury: a view from MESSENGER.

    PubMed

    Murchie, Scott L; Watters, Thomas R; Robinson, Mark S; Head, James W; Strom, Robert G; Chapman, Clark R; Solomon, Sean C; McClintock, William E; Prockter, Louise M; Domingue, Deborah L; Blewett, David T

    2008-07-01

    The Caloris basin, the youngest known large impact basin on Mercury, is revealed in MESSENGER images to be modified by volcanism and deformation in a manner distinct from that of lunar impact basins. The morphology and spatial distribution of basin materials themselves closely match lunar counterparts. Evidence for a volcanic origin of the basin's interior plains includes embayed craters on the basin floor and diffuse deposits surrounding rimless depressions interpreted to be of pyroclastic origin. Unlike lunar maria, the volcanic plains in Caloris are higher in albedo than surrounding basin materials and lack spectral evidence for ferrous iron-bearing silicates. Tectonic landforms, contractional wrinkle ridges and extensional troughs, have distributions and age relations different from their counterparts in and around lunar basins, indicating a different stress history. PMID:18599772

  10. Basins of attraction for chimera states

    NASA Astrophysics Data System (ADS)

    Martens, Erik A.; Panaggio, Mark J.; Abrams, Daniel M.

    2016-02-01

    Chimera states—curious symmetry-broken states in systems of identical coupled oscillators—typically occur only for certain initial conditions. Here we analyze their basins of attraction in a simple system comprised of two populations. Using perturbative analysis and numerical simulation we evaluate asymptotic states and associated destination maps, and demonstrate that basins form a complex twisting structure in phase space. Understanding the basins’ precise nature may help in the development of control methods to switch between chimera patterns, with possible technological and neural system applications.

  11. Drainage basins in Duval County, Florida

    USGS Publications Warehouse

    Stone, Roy B.; Largen, Joseph B.

    1983-01-01

    The drainage basins and subbasins in Duval County, Florida, are delineated on this atlas map. The county 's 840 square-mile area is drained by three major river systems; the St. Johns, 668 square miles; Nassau, 113 square miles; and St. Marys, 59 square miles. The remainder of the county is drained by a network of small streams that flow into either the Intracoastal Waterway or directly into the Atlantic Ocean. The sub-basins range in size from less than one square mile to more than 50 square miles. (USGS)

  12. Atlas of major Appalachian basin gas plays

    SciTech Connect

    Aminian, K.; Avary, K.L.; Baranoski, M.T.; Flaherty, K.; Humphreys, M.; Smosna, R.A.

    1995-06-01

    This regional study of gas reservoirs in the Appalachian basin has four main objectives: to organize all of the -as reservoirs in the Appalachian basin into unique plays based on common age, lithology, trap type and other geologic similarities; to write, illustrate and publish an atlas of major gas plays; to prepare and submit a digital data base of geologic, engineering and reservoir parameters for each gas field; and technology transfer to the oil and gas industry during the preparation of the atlas and data base.

  13. 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

  14. Science for the Changing Great Basin

    USGS Publications Warehouse

    Beever, Erik; Pyke, David A.

    2004-01-01

    The U.S. Geological Survey (USGS), with its multidisciplinary structure and role as a federal science organization, is well suited to provide integrated science in the Great Basin of the western United States. A research strategy developed by the USGS and collaborating partners addresses critical management issues in the basin, including invasive species, status and trends of wildlife populations and communities, wildfire, global climate change, and riparian and wetland habitats. Information obtained through implementation of this strategy will be important for decision-making by natural-resource managers.

  15. Ripple Ring Basins on Ganymede and Callisto

    NASA Technical Reports Server (NTRS)

    Croft, S. K.

    1985-01-01

    The unusual morphology of the Valhalla multiple or ripple-ring basin in Callisto was totally unexpected in light of the morphologies of large impact structures on the terrestrial planets. Two other ripple-ring basins (RRB's), Asgard and a smaller structure near the crater Adlinda are also described. Several additional RRB's were found on Callisto, an example of which is shown. A previously unrecognized RRB on Ganymede was also found. An image and geologic sketch map of this RRB are shown. Morphometric and positional data for all known RRB's are given.

  16. 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

  17. SimBasin: serious gaming for integrated decision-making in the Magdalena-Cauca basin

    NASA Astrophysics Data System (ADS)

    Craven, Joanne; Angarita, Hector; Corzo, Gerald

    2016-04-01

    The Magdalena-Cauca macrobasin covers 24% of the land area of Colombia, and provides more than half of the country's economic potential. The basin is also home a large proportion of Colombia's biodiversity. These conflicting demands have led to problems in the basin, including a dramatic fall in fish populations, additional flooding (such as the severe nationwide floods caused by the La Niña phenomenon in 2011), and habitat loss. It is generally believed that the solution to these conflicts is to manage the basin in a more integrated way, and bridge the gaps between decision-makers in different sectors and scientists. To this end, inter-ministerial agreements are being formulated and a decision support system is being developed by The Nature Conservancy Colombia. To engage stakeholders in this process SimBasin, a "serious game", has been developed. It is intended to act as a catalyst for bringing stakeholders together, an illustration of the uncertainties, relationships and feedbacks in the basin, and an accessible introduction to modelling and decision support for non-experts. During the game, groups of participants are led through a 30 year future development of the basin, during which they take decisions about the development of the basin and see the impacts on four different sectors: agriculture, hydropower, flood risk, and environment. These impacts are displayed through seven indicators, which players should try to maintain above critical thresholds. To communicate the effects of uncertainty and climate variability, players see the actual value of the indicator and also a band of possible values, so they can see if their decisions have actually reduced risk or if they just "got lucky". The game works as a layer on top of a WEAP water resources model of the basin, adapted from a basin-wide model already created, so the fictional game basin is conceptually similar to the Magdalena-Cauca basin. The game is freely available online, and new applications are being

  18. K West basin isolation barrier leak rate test

    SciTech Connect

    Whitehurst, R.; McCracken, K.; Papenfuss, J.N.

    1994-10-31

    This document establishes the procedure for performing the acceptance test on the two isolation barriers being installed in K West basin. This acceptance test procedure shall be used to: First establish a basin water loss rate prior to installation of the two isolation barriers between the main basin and the discharge chute in K-Basin West. Second, perform an acceptance test to verify an acceptable leakage rate through the barrier seals.

  19. A new survey of multiring impact basins on Mars

    SciTech Connect

    Schultz, R.A.; Frey, H.V. )

    1990-08-30

    Multiring impact basins have profoundly influenced the geologic evolution of Mars. The authors compile and summarize the evidence for Martian impact basins and suggest eight new examples. Multiring basins on Mars define three morphologic subclasses with increasing basin size. Basins having diameters 300 < D < 1,850 km are morphologically comparable to the classic lunar Orientale basin. Argyre type basins (1,850 < D < 3,600 km) are characterized by a rugged annulus and concentric grabens. The largest, Chryse type basins (D > 3,600 km) have extremely shallow topographic profiles and numerous concentric structures expressed as scarps, massifs, and channels. Radial and concentric structures analogous to those associated with Orientale are not apparent for basins of Argyre size or larger. These variations in basin morphology and structure may be associated with mechanical interactions between basin-forming impacts, relatively thin, weak lithosphere, and, for the largest impacts, spherical target geometry. Multiring basins are recognized on all parts of Mars, including Tharsis, Elysium, and the northern lowlands. Much of the subsequent resurfacing of cratered terrain such as Lunae Planum ridged plains is associated spatially with multiring basins. Nucleation of long-lived volcanic complexes in Tharsis and Elysium was probably aided by early impact basins. The planetary terrain dichotomy was probably established during the period of heavy meteoritic bombardment, and subsequent processes in the northern plains region were not sufficiently vigorous to destroy or completely obscure the underlying multiring basin fabric. The revised population of multiring basins is consistent with the size frequency distribution of craters < 500 km in diameter on Mars.

  20. Hydrology of the Johnson Creek Basin, Oregon

    USGS Publications Warehouse

    Lee, Karl K.; Snyder, Daniel T.

    2009-01-01

    The Johnson Creek basin is an important resource in the Portland, Oregon, metropolitan area. Johnson Creek forms a wildlife and recreational corridor through densely populated areas of the cities of Milwaukie, Portland, and Gresham, and rural and agricultural areas of Multnomah and Clackamas Counties. The basin has changed as a result of agricultural and urban development, stream channelization, and construction of roads, drains, and other features characteristic of human occupation. Flooding of Johnson Creek is a concern for the public and for water management officials. The interaction of the groundwater and surface-water systems in the Johnson Creek basin also is important. The occurrence of flooding from high groundwater discharge and from a rising water table prompted this study. As the Portland metropolitan area continues to grow, human-induced effects on streams in the Johnson Creek basin will continue. This report provides information on the groundwater and surface-water systems over a range of hydrologic conditions, as well as the interaction these of systems, and will aid in management of water resources in the area. High and low flows of Crystal Springs Creek, a tributary to Johnson Creek, were explained by streamflow and groundwater levels collected for this study, and results from previous studies. High flows of Crystal Springs Creek began in summer 1996, and did not diminish until 2000. Low streamflow of Crystal Springs Creek occurred in 2005. Flow of Crystal Springs Creek related to water-level fluctuations in a nearby well, enabling prediction of streamflow based on groundwater level. Holgate Lake is an ephemeral lake in Southeast Portland that has inundated residential areas several times since the 1940s. The water-surface elevation of the lake closely tracked the elevation of the water table in a nearby well, indicating that the occurrence of the lake is an expression of the water table. Antecedent conditions of the groundwater level and autumn

  1. Integrated Worker Radiation Dose Assessment for the K Basins

    SciTech Connect

    NELSON, J.V.

    1999-10-27

    This report documents an assessment of the radiation dose workers at the K Basins are expected to receive in the process of removing spent nuclear fuel from the storage basins. The K Basins (K East and K West) are located in the Hanford 100K Area.

  2. River basins of the United States: the Colorado

    USGS Publications Warehouse

    ,

    1987-01-01

    This leaflet, one of a series on the river basins of the United States, contains information on the Colorado River Basin, including a brief early history, a description of the physical characteristics, and other statistical data. At present, other river basins included in the series are The Columbia, The Delaware, The Hudson, The Potomac, and The Wabash.

  3. 75 FR 8895 - Basin Electric Power Cooperative: Deer Creek Station

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-26

    ...; ] DEPARTMENT OF AGRICULTURE Rural Utilities Service Basin Electric Power Cooperative: Deer Creek Station AGENCY.... SUMMARY: The Rural Utilities Service (RUS) and the Western Area Power Administration (Western) have issued... potential environmental impacts of and alternatives to Basin Electric Power Cooperative's (Basin...

  4. Work plan for 105KE Basin seal conveyor relocation

    SciTech Connect

    Tedeschi, D.J.

    1994-08-25

    This engineering work plan will support the activities of a pilot encapsulation of the spent fuel rods at 105KE Basin for the Hanford Site. The plan is to move and resue any existing encapsulation equipment in the Basin to another part of the Basin. This plan will discuss the activities involved in moving the seal conveyor system.

  5. 48 CFR 25.405 - Caribbean Basin Trade Initiative.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... must be treated as eligible products. In accordance with Section 201 (a)(3) of the Dominican Republic... country for purposes of the Caribbean Basin Economic Recovery Act, and is therefore no longer included in the definition of “Caribbean Basin country” for purposes of the Caribbean Basin Trade Initiative....

  6. Beijing Basin's amplification effect on long-period ground motion

    NASA Astrophysics Data System (ADS)

    Fu, Changhua

    2016-04-01

    A lot of high-rise buildings are located in basins. Previous researches tell us that the intensity of long-period ground motion in the basin is usually larger than that in its vicinities when a strong earthquake occurs. This higher intensity will cause severe damage to high-rise buildings which have long self-vibrating periods. So, by studying the characteristics of ground motion in the basin and analyzing basin amplification effect on long-period ground motion, we can understand reasonable seismic fortification requirement of high-rise buildings in the basin, and provide scientific reference for city future planning, earthquake emergency and rescue. Taking Beijing Basin as an example, we set up several scenario earthquakes, then use Ground-Motion-Simulation method to study how different scenario earthquakes influence basin's amplification effect on long-period ground motion. The research demonstrates that the amplification effect on 3~10-second ground motion acceleration response spectrum is mainly controlled by thickness of sediment in basin, although different seismic sources may cause the uncertainty to a certain extent. Thus, the average basin's amplification factor on 3~10-second ground motion acceleration response spectrum is computed, and the correlation function, that between the average amplification factor and equivalent thickness of sediment in basin, is analyzed. Finally, according to the distribution of high-rise buildings in Beijing Basin, preliminary discussion on the relationship between risk level of seismic hazard of high-rise buildings and basin structure is made.

  7. 75 FR 66389 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-28

    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  8. 76 FR 61382 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-04

    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. ] SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  9. 76 FR 24515 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of... Committee Act, the Bureau of Reclamation announces that the Colorado River Basin Salinity Control Advisory...) 524-3826; e-mail at: kjacobson@usbr.gov . SUPPLEMENTARY INFORMATION: The Colorado River Basin...

  10. 48 CFR 25.405 - Caribbean Basin Trade Initiative.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Caribbean Basin Trade... SOCIOECONOMIC PROGRAMS FOREIGN ACQUISITION Trade Agreements 25.405 Caribbean Basin Trade Initiative. Under the Caribbean Basin Trade Initiative, the United States Trade Representative has determined that,...

  11. 48 CFR 25.405 - Caribbean Basin Trade Initiative.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Caribbean Basin Trade... SOCIOECONOMIC PROGRAMS FOREIGN ACQUISITION Trade Agreements 25.405 Caribbean Basin Trade Initiative. Under the Caribbean Basin Trade Initiative, the United States Trade Representative has determined that,...

  12. 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...

  13. Notice of release of 'Trailhead II' basin wildrye

    Technology Transfer Automated Retrieval System (TEKTRAN)

    'Trailhead II' basin wildrye [Leymus cinereus (Scribn. & Merr.) A. Love] is a tetraploid basin wildrye release for use in re-vegetation efforts on rangelands of western North America. Trailhead II is the result of two cycles of recurrent selection within the basin wildrye cultivar 'Trailhead' for r...

  14. Evaluation of cross-protection between O1 Manisa and O1 Campos in cattle vaccinated with foot-and-mouth disease virus vaccine incorporating different payloads of inactivated O1 Manisa antigen.

    PubMed

    Nagendrakumar, Singanallur Balasubramanian; Srinivasan, Villuppanoor Alwar; Madhanmohan, Muthukrishnan; Yuvaraj, Shanmugam; Parida, Satya; Di Nardo, Antonello; Horsington, Jacquelyn; Paton, David James

    2011-02-24

    Serology is used to predict vaccine induced protection against challenge with a heterologous strain of the same serotype of foot-and-mouth disease virus (FMDV). To evaluate the accuracy of such predictions, we compared the protection afforded to cattle vaccinated with the O(1) Manisa strain of FMDV against challenge with either a homologous (O(1) Manisa) or a heterologous strain (O(1) Campos). Serology by virus neutralization test (VNT) using O(1) Manisa antiserum predicted an acceptable protection against such a challenge. Two experiments were carried out to compare the results for consistency. A total of 78 naïve cattle were vaccinated with different antigen payloads (60-0.94 μg) of O(1) Manisa. They were challenged by intradermolingual inoculation with live FMDV, either O(1) Manisa or O(1) Campos. Unvaccinated naïve control cattle (n=20) were also challenged with either the O(1) Manisa or O(1) Campos viruses and all developed generalized FMD. The protection results for the vaccinated cattle revealed that higher payloads of O(1) Manisa vaccine were needed to protect against heterologous challenge compared to that for homologous challenge. The 50% protective dose (PD(50)) values for the vaccine in experiments 1 and 2 were found to be 28.78 and 9.44 for the homologous challenge and 3.98 and 5.01 for heterologous challenge. Furthermore, protection against O(1) Campos required a higher level of vaccine-induced antibody against this virus compared to the level of O(1) Manisa neutralizing antibody associated with protection against homologous challenge. The 50% protective level of in vitro neutralizing antibody was found to be log(10)1.827 for O(1) Campos and log(10)0.954 for O(1) Manisa based on O(1) Manisa based virus neutralization test.

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

    SciTech Connect

    Ernest A. Mancini; Donald A. Goddard

    2005-08-01

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

  16. Basin development and tectonic history of the Llanos Basin, Eastern Cordillera, and Middle Magdalena Valley, Colombia

    SciTech Connect

    Cooper, M.A.; Addison, F.T.; Alvarez, R.

    1995-10-01

    The Middle Magdalena Valley, Eastern Cordillera, and Llanos basin constituted a major regional sedimentary basin from the Triassic to the middle Miocene. Basin development began during the Triassic to the earliest Cretaceous with a synrift megasequence related to the separation of North and South America in the proto-Caribbean. The synrift megasequence began with deposition in a continental environment that became paralic and shallow marine in the Early Cretaceous. Basin development continued into the Cretaceous in a back-arc setting east of the Andean subduction zone. The back-arc megasequence was dominated by shallow-marine sedimentation and produced an excellent regional source rock during the Turonian-Coniacian. Marine deposition was abruptly terminated during the early Maastrichtian due to the final accretion of the Western Cordillera.

  17. Somali Basin, Chain Ridge, and origin of the Northern Somali Basin gravity and geoid low

    NASA Technical Reports Server (NTRS)

    Cochran, James R.

    1988-01-01

    Geophysical data are used to investigate the origin of the Northern Somali Basin and its relationship to surrounding tectonic elements. The results show the Northern Somali Basin to be the third of a series of oceanic basins separated by long transform faults created during movement between East and West Gondwanaland. The flexure resulting from differential subsidence across Chain Ridge along with the difference in lithospheric thermal structure on either side of it can account for the amplitude and shape of the observed geoid step and gravity anomalies across Chain Rige. It is suggested that the geoid and gravity low over the Northern Somali Basin may result from the superposition of a continental edge effect anomaly and the fracture zone edge effect anomaly.

  18. Potential for a basin-centered gas accumulation in the Raton Basin, Colorado and New Mexico

    USGS Publications Warehouse

    Johnson, Ronald C.; Finn, Thomas M.

    2001-01-01

    The Raton Basin appears to contain a significant continuous or basin-centered gas accumulation in sandstones of the Upper Cretaceous Trinidad Sandstone and Vermejo Formation and Upper Cretaceous and Paleocene Raton Formation. The accumulation is underpressured and occurs at comparatively shallow (<3,500 ft) depths. The sandstones are interbedded with coal beds that are currently being developed for coal-bed methane, and the coals are the likely source for gas found in the sandstones. Based on analogs with other Rocky Mountain basins, relatively water-free production should occur where levels of thermal maturity in the coals exceed a vitrinite reflectance value of 1.1 percent. This level of thermal maturity occurs over much of the central part of the Raton Basin. Because of the shallow depths, some of the accumulation has probably been degraded by surface water invasion.

  19. Ghaba salt basin province and Fahud salt basin province, Oman; geological overview and total petroleum systems

    USGS Publications Warehouse

    Pollastro, Richard M.

    1999-01-01

    Three Total Petroleum Systems each consisting of one assessment unit have been identified in the Ghaba and Fahud Salt Basin Provinces of north-central Oman. One Total Petroleum System and corresponding assessment unit, the North Oman Huqf/?Q??Haushi(!) Total Petroleum System (201401) and Ghaba- Makarem Combined Structural Assessment Unit (20140101), were identified for the Ghaba Salt Basin Province (2014). In the Fahud Salt Basin Province, however, two overlapping Total Petroleum Systems (TPS) were recognized: (1) the North Oman Huqf?Shu?aiba(!) TPS (201601); Fahud-Huqf Combined Structural Assessment Unit (20160101), and (2) the middle Cretaceous Natih(!) TPS (201602); Natih-Fiqa Structural/Stratigraphic Assessment Unit (20160201). The boundary for each Total Petroleum System also defines the boundary of the corresponding assessment unit and includes all trap styles and hydrocarbon-producing reservoirs within the petroleum system. In both the Ghaba and Fahud Salt Basin Provinces, hydrocarbons were generated from several deeply buried source rocks within the Infracambrian Huqf Supergroup. One general ?North Oman Huqf? type oil is dominant in the Fahud Salt Basin. Oils in the Ghaba Salt Basin are linked to at least two distinct Huqf source-rock units based on oil geochemistry: a general North Oman Huqf-type oil source and a more dominant ?questionable unidentified source? or ?Q?-type Huqf oil source. These two Huqf-sourced oils are commonly found as admixtures in reservoirs throughout northcentral Oman. Hydrocarbons generated from Huqf sources are produced from a variety of reservoir types and ages ranging from Precambrian to Cretaceous in both the Ghaba and Fahud Salt Basin Provinces. Clastic reservoirs of the Gharif and Al Khlata Formations, Haushi Group (middle Carboniferous to Lower Permian), dominate oil production in the Ghaba Salt Basin Province and form the basis for the Huqf/?Q??Haushi(!) TPS. In contrast, the Lower Cretaceous Shu?aiba and middle Cretaceous

  20. Composition of Orientale basin deposits and implications for the lunar basin-forming process

    NASA Technical Reports Server (NTRS)

    Spudis, P. D.; Hawke, B. R.; Lucey, P.

    1984-01-01

    The geologic, spectral and geochemical characteristics of the lunar Orientale basin are discussed, and a model is defined for the generation of Orientale basin deposits. The data indicate that the basin ejecta is composed mainly of anorthositic deposits and no crustal material. The crater was originally 500-600 km across and 50-60 km deep, the latter being too shallow to reach the projected 100 km crustal depth. A proportional growth model is judged acceptable for the Orientale basin. Finally, it is concluded that neither the Apollo 14 nor 16 missions obtained Orientale ejecta material, which could in any case be unidentifiable until more thorough samplings are made of a large portion of the lunar surface.

  1. Cenozoic synthem stratigraphic architecture of the SE Brazilian shelf and its global eustatic context: evidence from the Pelotas Basin (offshore Brazil)

    NASA Astrophysics Data System (ADS)

    de Santana dos Anjos Zerfass, Geise; Ruban, Dmitry A.; Chemale, Farid, Jr.; Zerfass, Henrique

    2013-12-01

    The Pelotas Basin, located on the SE Brazilian shelf, has evolved since the Aptian. Stratigraphical data from the basin can be used for delineation of the unconformity-bounded units (synthems) on the shelf, which is a first step towards a full understanding of its stratigraphic architecture, evolution, and hydrocarbon potential. Hiatuses in the Cenozoic succession of the Pelotas Basin are established with both biostratigraphic (planktonic foraminifers and calcareous nannofossils) and isotopic (87Sr/86Sr) data. The seven recognised hiatuses are dated respectively as (1) Palaeocene (Danian- Thanetian), (2) Palaeocene/Eocene boundary (Thanetian-Ypresian), (3) Eocene (Ypresian-Lutetian), (4) Eocene-Oligocene (Lutetian-Rupelian), (5) early-late Oligocene (Rupelian-Chattian), (6) early Miocene (Aquitanian-Burdigalian), and (7) middle-late Miocene (Serravallian-Tortonian). These intervals between the hiatuses are correlated with those of the Santos and Campos Basins north from the Pelotas Basin. The breaks in sedimentation that these basins have in common occurred (1) at the Palaeocene-Eocene and (2) Eocene-Oligocene transitions, (3) in the early Miocene, and (4) in the middle-late Miocene. These main unconformities outline five synthems on the SE Brazilian shelf, viz. the SEBS-1 (Palaeocene), SEBS-2 (Eocene), SEBS-3 (Oligocene), SEBS-4 (early-middle Miocene) and SEBS-5 (late Miocene-Holocene). The above unconformities are correlated with those established in the Cenozoic sedimentary successions of different regions such as Western Siberia, Arabia, NW and NE Africa, peninsular India, S Australia, the Gulf of Mexico, NW Europe, and South Africa. The only regional unconformity, near the Oligocene/Miocene boundary, coincides with the nearly-global sedimentation break. The latter was resulted from a climatic event, i.e., the `Mi-1 glaciation'. Thus, a eustatic origin is supposed for this regional unconformity. The other regional unconformities also correspond to global sea

  2. Historical Orthoimagery of the Lake Tahoe Basin

    USGS Publications Warehouse

    Soulard, Christopher E.; Raumann, Christian G.

    2008-01-01

    The U.S. Geological Survey (USGS) Western Geographic Science Center has developed a series of historical digital orthoimagery (HDO) datasets covering part or all of the Lake Tahoe Basin. Three datasets are available: (A) 1940 HDOs for the southern Lake Tahoe Basin, (B) 1969 HDOs for the entire Lake Tahoe Basin, and (C) 1987 HDOs for the southern Lake Tahoe Basin. The HDOs (for 1940, 1969, and 1987) were compiled photogrammically from aerial photography with varying scales, camera characteristics, image quality, and capture dates. The resulting datasets have a 1-meter horizontal resolution. Precision-corrected Ikonos multispectral satellite imagery was used as a substitute for HDOs/DOQs for the 2002 imagery date, but these data are not available for download in this series due to licensing restrictions. The projection of the HDO data is set to UTM Zone 10, NAD 1983. The data for each of the three available dates are clipped into files that spatially approximate the 3.75-minute USGS quarter quadrangles (roughly 3,000 to 4,000 hectares), and have roughly 100 pixels (or 100 meters) of overlap to facilitate combining the files into larger regions without data gaps. The files are named after 3.75-minute USGS quarter quadrangles that cover the same general spatial extent. These files are available in the ERDAS Imagine (.img) format.

  3. Water Quality in the Yukon River Basin

    USGS Publications Warehouse

    Brabets, Timothy P.; Hooper, Rick; Landa, Ed

    2001-01-01

    The Yukon River Basin, which encompasses 330,000 square miles in northwestern Canada and central Alaska (Fig. 1), is one of the largest and most diverse ecosystems in North America. The Yukon River is also fundamental to the ecosystems of the eastern Bering Sea and Chukchi Sea, providing most of the freshwater runoff, sediments, and dissolved solutes. Despite its remoteness and perceived invulnerability, the Yukon River Basin is changing. For example, records of air temperature during 1961-1990 indicate a warming trend of about 0.75 deg C per decade at latitudes where the Yukon River is located. Increases in temperature will have wide-ranging effects on permafrost distribution, glacial runoff and the movement of carbon and nutrients within and from the basin. In addition, Alaska has many natural resources such as timber, minerals, gas, and oil that may be developed in future years. As a consequence of these changes, several issues of scientific and cultural concern have come to the forefront. At present, water quality data for the Yukon River Basin are very limited. This fact sheet describes a program to provide the data that are needed to address these issues.

  4. Seismic solutions in the Val Verde basin

    SciTech Connect

    Underwood, J.D.; Nickoloff, T.R. )

    1992-04-01

    The Val Verde basin has been an underexplored basin, despite the discovery of world-class gas fields on the northern edge of the basin in the 1950s and the 1960s, because the basin was opaque to conventional seismic reflection methods. Permian Exploration was approached in 1988 to design an acquisition geometry and processing sequence that would produce data that could be used with confidence. A field test was designed to test the hypothesis that the high Q limestones at the surface of the mesas were reflecting source generated noise into receiver lines from cross-line directions. That test crossed both mesa and valley terrains and looked for noise arriving from all directions. Analysis of the test data showed that cross-line coherent noise was a significant problem and that unconventional techniques were necessary to record the reflected signal. Acquisiton of data using multiline techniques, coupled with new high-channel recording systems, exhaustive statics analysis, and powerful noise cancellation algorithms has given data the interpreter can use with confidence.

  5. A-D. Evolution of sedimentary basins

    SciTech Connect

    Not Available

    1988-01-01

    This book includes the first four chapters in a bulletin series on the evolution of the Appalachian Basin. Structural, tectonic, sedimentologic, and conodont color alteration studies are presented, and the implications of the results of these studies on hydrocarbon potential in the area are discussed.

  6. KE Basin underwater visual fuel survey

    SciTech Connect

    Pitner, A.L.

    1995-02-01

    Results of an underwater video fuel survey in KE Basin using a high resolution camera system are presented. Quantitative and qualitative information on fuel degradation are given, and estimates of the total fraction of ruptured fuel elements are provided. Representative photographic illustrations showing the range of fuel conditions observed in the survey are included.

  7. Aquifers of the Denver Basin, Colorado

    USGS Publications Warehouse

    Topper, R.

    2004-01-01

    Development of the Denver Basin for water supply has been ongoing since the late 1800s. The Denver Basin aquifer system consists of the water-yielding strata of Tertiary and Cretaceous sedimentary rocks within four overlying formations. The four statutory aquifers contained in these formations are named the Dawson, Denver, Arapahoe, and Laramie-Fox Hills. For water rights administrative purposes, the outcrop/subcrop of the Laramie-Fox Hills aquifer defines the margins of the Basin. Initial estimates of the total recoverable groundwater reserves in storage, under this 6700-mi2 area, were 295 million acre-ft. Recent geologic evidence indicates that the aquifers are very heterogeneous and their composition varies significantly with distance from the source area of the sediments. As a result, available recoverable reserves may be one-third less than previously estimated. There is no legal protection for pressure levels in the aquifer, and water managers are becoming increasingly concerned about the rapid water level declines (30 ft/yr). Approximately 33,700 wells of record have been completed in the sedimentary rock aquifers of the Denver Basin for municipal, industrial, agricultural, and domestic uses.

  8. Classifying and quantifying basins of attraction

    SciTech Connect

    Sprott, J. C.; Xiong, Anda

    2015-08-15

    A scheme is proposed to classify the basins for attractors of dynamical systems in arbitrary dimensions. There are four basic classes depending on their size and extent, and each class can be further quantified to facilitate comparisons. The calculation uses a Monte Carlo method and is applied to numerous common dissipative chaotic maps and flows in various dimensions.

  9. Hydrological trends in Congo basin (Central Africa)

    NASA Astrophysics Data System (ADS)

    Laraque, A.

    2015-12-01

    The last studies concerning some main Congo basin rivers allowed to subdivide their multi-annual flows into several homogeneous phases. As in West Africa, 1970 was the year of the major hydroclimatic event announcing a weaker flowing period. In the absence of long, reliable and available flow series in the whole Congo basin of 3,8 106km2 area, the present study concerns only the Congo River at Brazzaville/Kinshasa and two of the main tributaries of its right bank, Ubangui at Bangui and Sangha at Ouesso, with hydrologic data available from the first half of the 20th century. For Congo River, in comparison with its secular average, after an excess flow noted during the sixties, a significant drop of 10% occurs in the eighties. However, a return to normal conditions is recorded from 1995. For Ubangui and Sangha, the flows remain weaker since 1970. Within the bi-modal hydrological regimes of Sangha and Congo river, because they are equatorial, we also observe since many years a small decline of the secondary flood of april-june. This phenomenon was emphasized especially these last years and is founded in others rivers of Central Africa, where it reflects the variations of de rainfall patterns and the surfaces features. For the Congo basin, the situation is worrying because that affects the inland waterway transport. Moreover that wakes also the project of junction by a canal of the Congo and Chari basins for fighting against the hydrological decline of Lake Chad.

  10. The Great Basin Research and Management Partnership

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Great Basin is undergoing major sociological and ecological change as a result of urbanization, changing technology and land use, climate change, limited water resources, altered fire regimes, and invasive species, insects, and disease. Sustaining ecosystems, resources, and human populations of...

  11. Central Mississippi River Basin LTAR site overview

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Central Mississippi River Basin (CMRB) member of the Long-Term Agro-ecosystem Research (LTAR) network is representative of the southern Corn Belt, where subsoil clay content makes tile drainage challenging and make surface runoff and associated erosion problematic. Substantial research infrastru...

  12. Tularosa Basin Play Fairway Analysis: Strain Analysis

    SciTech Connect

    Adam Brandt

    2015-11-15

    A DEM of the Tularosa Basin was divided into twelve zones, each of which a ZR ratio was calculated for. This submission has a TIFF image of the zoning designations, along with a table with respective ZR ratio calculations in the metadata.

  13. Plate evolution and petroliferous basins of China

    SciTech Connect

    Wu Shou Cheng; Zhang Wen Zhao

    1989-03-01

    The writers have compiled a group of paleogeographic and paleostructural maps of tectonic plates and sedimentary basins of China based on paleomagnetic, paleoclimatic, and paleoecologic data. The paleoenvironments and regional conditions that instigated the origin of petroleum in the superbasins have been reconstructed.

  14. Hydrocarbon potential of intracratonic rift basins

    SciTech Connect

    Baker, D.G.; Derksen, S.J.

    1984-09-01

    Significant world oil reserves have been added in recent years from rift system. Examples of petroliferous rift basins may be found on nearly every major continent. As our understanding of the mechanisms of sedimentation and structure in rift basins grows, more rift systems will be found. With a few notable exceptions, rifts that have been explored in the past are those that formed along continental margins. These contain marine sediments, and the conditions of source rock, sediment type, depositional environment, and structural style are well-known exploration concepts. Intracratonic rift systems containing continental sediments, and also because of the problems perceived to accompany continental sedimentation. A good modern analog is the East African rift system. Several companies have made significant oil discoveries in different components of the Central African rift system. Average daily production for 1982 from the basins associated with the Benue trough was 107.928 BOPD. In the Abu Gabra rift component, where Marathon is currently exploring, Chevron has drilled approximately 60 wells. Nineteen of these were discoveries and tested an average rate per well of 3,500 BOPD. The Abu Gabra rift may contain up to 10 billion bbl of oil. Research indicates that this type of rift system is present in other areas of the world. Ongoing worldwide exploration has shown that intracratonic rift basins have the potential to make a significant contribution to world oil reserves.

  15. Stochastic basins of attraction for metastable states

    NASA Astrophysics Data System (ADS)

    Serdukova, Larissa; Zheng, Yayun; Duan, Jinqiao; Kurths, Jürgen

    2016-07-01

    Basin of attraction of a stable equilibrium point is an effective concept for stability analysis in deterministic systems; however, it does not contain information on the external perturbations that may affect it. Here we introduce the concept of stochastic basin of attraction (SBA) by incorporating a suitable probabilistic notion of basin. We define criteria for the size of the SBA based on the escape probability, which is one of the deterministic quantities that carry dynamical information and can be used to quantify dynamical behavior of the corresponding stochastic basin of attraction. SBA is an efficient tool to describe the metastable phenomena complementing the known exit time, escape probability, or relaxation time. Moreover, the geometric structure of SBA gives additional insight into the system's dynamical behavior, which is important for theoretical and practical reasons. This concept can be used not only in models with small noise intensity but also with noise whose amplitude is proportional or in general is a function of an order parameter. As an application of our main results, we analyze a three potential well system perturbed by two types of noise: Brownian motion and non-Gaussian α-stable Lévy motion. Our main conclusions are that the thermal fluctuations stabilize the metastable system with an asymmetric three-well potential but have the opposite effect for a symmetric one. For Lévy noise with larger jumps and lower jump frequencies ( α = 0.5 ) metastability is enhanced for both symmetric and asymmetric potentials.

  16. Columbia Basin College Facts & Impacts, 2002.

    ERIC Educational Resources Information Center

    Columbia Basin Coll., Pasco, WA.

    This fact book for Columbia Basin College (CBC) (Washington) offers statistics on staff and faculty, students, degrees awarded, hot programs, enrollment; student services, financial aid, economic impact, educational partnerships, and governance. CBC serves more than 13,000 students annually and offers associate degrees in arts, science, and…

  17. Seasonal Streamflow Forecasts for African Basins

    NASA Astrophysics Data System (ADS)

    Serrat-Capdevila, A.; Valdes, J. B.; Wi, S.; Roy, T.; Roberts, J. B.; Robertson, F. R.; Demaria, E. M.

    2015-12-01

    Using high resolution downscaled seasonal meteorological forecasts we present the development and evaluation of seasonal hydrologic forecasts with Stakeholder Agencies for selected African basins. The meteorological forecasts are produced using the Bias Correction and Spatial Disaggregation (BCSD) methodology applied to NMME hindcasts (North American Multi-Model Ensemble prediction system) to generate a bootstrap resampling of plausible weather forecasts from historical observational data. This set of downscaled forecasts is then used to drive hydrologic models to produce a range of forecasts with uncertainty estimates suitable for water resources planning in African pilot basins (i.e. Upper Zambezi, Mara Basin). In an effort to characterize the utility of these forecasts, we will present an evaluation of these forecast ensembles over the pilot basins, and discuss insights as to their operational applicability by regional actors. Further, these forecasts will be contrasted with those from a standard Ensemble Streamflow Prediction (ESP) approach to seasonal forecasting. The case studies presented here have been developed in the setting of the NASA SERVIR Applied Sciences Team and within the broader context of operational seasonal forecasting in Africa. These efforts are part of a dialogue with relevant planning and management agencies and institutions in Africa, which are in turn exploring how to best use uncertain forecasts for decision making.

  18. Drilling bits optimized for the Paris basin

    SciTech Connect

    Vennin, H.C. Pouyastruc )

    1989-07-31

    Paris basin wells have been successfully drilled using steel-body bits with stud-type cutters. These bits offer the possibility of optimizing the bit-face based on the strata to be drilled, as well as allowing replacement of worn cutters. This article discusses: bit manufacturing; bit repair; optimizing bits; hydraulics.

  19. Petroleum geology in Tarim basin, China

    SciTech Connect

    Zhou, Guojun )

    1994-08-01

    Tarim basin is a superimposed basin with two tectonic regimes and contains multisources, multireservoirs, and multiseals. Almost all major strata within the Paleozoic, Mesozoic, and Cenozoic exist in the basin, and they are grouped by six regional unconformities, which are related to hydrocarbon accumulation. Source rocks are Cambrian marl; Lower Ordovician black carbonaceous shales; Middle Ordovician dark gray limestone; Upper Ordovician brownish black carbonaceous shales and oil shales; grayish black carbonaceous shales, dark gray and grayish brown bituminous marl, and reef limestone in the Carboniferous and Permian; and gray to dark gray shales in the Triassic-Jurassic oil-bearing strata. Reservoir rocks in the Cambrian-Ordovician oil-bearing strata and the Carboniferous-Permian oil-bearing strata are mainly fractured limestones and sandstones. The fracture distribution is related to unconformities. Vugs and casts also exist in most limestones; intergranular porosity exists in sandstones. The reservoirs in the Triassic-Jurassic are fluvial-deltaic sandstones, and above are Cretaceous gypsum and halite seals. Ten types of traps are found in this basin: (1) fold-related anticline traps, (2) anticline-fault traps, (3) fault drag-related anticline traps, (4) traps underneath thrusting faults, (5) fault-block traps (6) traps made from cross or arc-like fault and monocline, (7) salt dome traps, (8) traps created by intrusion, (9) lenticular or pinchout traps, and (10) unconformity and overlap traps.

  20. Nutrient levels in the Yazoo River Basin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High nitrogen (N) and phosphorus (P) loadings to aquatic ecosystems are linked to environmental problems including harmful algal blooms and hypoxia. Presented is an assessment of accessible data on nutrient sources, sinks and inputs to streams within the Yazoo River Basin of northern Mississippi. Ac...

  1. Summary status of K Basins sludge characterization

    SciTech Connect

    Baker, R.B.

    1995-01-20

    A number of activities are underway as part of the Spent Nuclear Fuels Project (SNFP) related to the processing and disposing of sludge in the 105-K Basins (K Basins). Efforts to rigorously define data requirements for these activities are being made using the Data Quality Objectives (DQO) process. Summaries of current sludge characterization data are required to both help support this DQO process and to allow continued progress with on-going engineering activities (e.g., evaluations of disposal alternatives). This document provides the status of K Basins sludge characterization data currently available to the Nuclear Fuel Evaluations group. This group is tasked by the SNFP to help develop and maintain the characterization baseline for the K Basins. The specific objectives of this document are to: (1) provide a current summary (and set of references) of sludge characterization data for use by SNFP initiatives, to avoid unnecessary duplication of effort and to support on-going initiatives; (2) submit these data to an open forum for review and comment, and identify additional sources of significant data that may be available; (3) provide a summary of current data to use as part of the basis to develop requirements for additional sludge characterization data through the DQO process; (4) provide an overview of the intended activities that will be used to develop and maintain the sludge characterization baseline.

  2. Atmospheric dispersion in mountain valleys and basins

    SciTech Connect

    Allwine, K.J.

    1992-01-01

    The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ``ventilation rate`` of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.

  3. Atmospheric dispersion in mountain valleys and basins

    SciTech Connect

    Allwine, K.J.

    1992-01-01

    The primary goal of the research is to further characterize and understand dispersion in valley and basin atmospheres. A secondary, and related goal, is to identify and understand the dominant physical processes governing this dispersion. This has been accomplished through a review of the current literature, and analyses of recently collected data from two field experiments. This work should contribute to an improved understanding of material transport in the atmospheric boundary layer. It was found that dispersion in a freely draining valley (Brush Creek valley, CO) atmosphere is much greater than in an enclosed basin (Roanoke, VA) atmosphere primarily because of the greater wind speeds moving past the release point and the greater turbulence levels. The development of a cold air pool in the Roanoke basin is the dominant process governing nighttime dispersion in the basin, while the nighttime dispersion in the Brush Creek valley is dominated by turbulent diffusion and plume confinement between the valley sidewalls. The interaction between valley flows and above ridgetops flows is investigated. A ventilation rate'' of material transport between the valley and above ridgetop flows is determined. This is important in regional air pollution modeling and global climate modeling. A simple model of dispersion in valleys, applicable through a diurnal cycle, is proposed.

  4. Starting a Business in the Permian Basin.

    ERIC Educational Resources Information Center

    Harrison, Danny

    The business and economic development center of Midland College provides assistance to small businesses. Written for use by future and current small business owners and entrepreneurs living in a 17-county area of the Permian Basin of Texas, this guidebook describes the procedures for developing a business plan and for successfully starting and…

  5. SE Great Basin Play Fairway Analysis

    DOE Data Explorer

    Adam Brandt

    2015-11-15

    Within this submission are multiple .tif images with accompanying metadata of magnetotelluric conductor occurrence, fault critical stress composite risk segment (CRS), permeability CRS, Quaternary mafic extrusions, Quaternary fault density, and Quaternary rhyolite maps. Each of these contributed to a final play fairway analysis (PFA) for the SE Great Basin study area.

  6. Tularosa Basin Play Fairway Analysis: Water Chemistry

    DOE Data Explorer

    Adam Brandt

    2015-12-15

    This shapefile contains 409 well data points on Tularosa Basin Water Chemistry, each of which have a location (UTM), temperature, quartz and Potassium/Magnesium geothermometer; as well as concentrations of chemicals like Mn, Fe, Ba, Sr, Cs, Rb, As, NH4, HCO3, SO4, F, Cl, B, SiO2, Mg, Ca, K, Na, and Li.

  7. Stochastic basins of attraction for metastable states.

    PubMed

    Serdukova, Larissa; Zheng, Yayun; Duan, Jinqiao; Kurths, Jürgen

    2016-07-01

    Basin of attraction of a stable equilibrium point is an effective concept for stability analysis in deterministic systems; however, it does not contain information on the external perturbations that may affect it. Here we introduce the concept of stochastic basin of attraction (SBA) by incorporating a suitable probabilistic notion of basin. We define criteria for the size of the SBA based on the escape probability, which is one of the deterministic quantities that carry dynamical information and can be used to quantify dynamical behavior of the corresponding stochastic basin of attraction. SBA is an efficient tool to describe the metastable phenomena complementing the known exit time, escape probability, or relaxation time. Moreover, the geometric structure of SBA gives additional insight into the system's dynamical behavior, which is important for theoretical and practical reasons. This concept can be used not only in models with small noise intensity but also with noise whose amplitude is proportional or in general is a function of an order parameter. As an application of our main results, we analyze a three potential well system perturbed by two types of noise: Brownian motion and non-Gaussian α-stable Lévy motion. Our main conclusions are that the thermal fluctuations stabilize the metastable system with an asymmetric three-well potential but have the opposite effect for a symmetric one. For Lévy noise with larger jumps and lower jump frequencies ( α=0.5) metastability is enhanced for both symmetric and asymmetric potentials. PMID:27475077

  8. Exploration in Ordovician of central Michigan Basin

    SciTech Connect

    Fisher, J.H.; Barratt, M.W.

    1985-12-01

    Deep wells in the central Michigan basin have provided sufficient data to define two new mappable formations - the Foster Formation and the Bruggers Formation. Recent conodont studies have corrected the age assignments of the strata containing these formations. Previously, the lower section (Foster) was classified as mostly Cambrian, and the upper unit (Bruggers) was identified as Early Ordovician. Conodont identifications indicate an Early and Middle Ordovician age for the Foster Formation and a Middle Ordovician age for the Bruggers Formation. The Michigan basin existed in embryonic form in the Late Cambrian, but the full outline of the present-day basin did not develop until Early Ordovician. Gas and condensate are produced from the Bruggers Formation as deep as 11,252 ft (3429 m). Geothermal investigations suggest that gas production is possible to the base of the Paleozoic section in the central basin (17,000 ft or 5181 m). Paleotemperatures were higher during the Paleozoic owing to 3000-4000 ft (914-1291 m) of additional sedimentary cover. Five wells are producing from the Bruggers Formation. All are deeper tests in anticlines producing from Devonian reservoirs discovered earlier. The structures are the result of vertical movements of basement fault blocks activated by regional stresses. 12 figures, 2 tables.

  9. Poyang Lake basin: a successful, large-scale integrated basin management model for developing countries.

    PubMed

    Chen, Meiqiu; Wei, Xiaohua; Huang, Hongsheng; Lü, Tiangui

    2011-01-01

    Protection of water environment while developing socio-economy is a challenging task for lake regions of many developing countries. Poyang Lake is the largest fresh water lake in China, with its total drainage area of 160,000 km2. In spite of rapid development of socio-economy in Poyang Lake region in the past several decades, water in Poyang Lake is of good quality and is known as the "last pot of clear water" of the Yangtze River Basin in China. In this paper, the reasons of "last pot of clear water" of Poyang Lake were analysed to demonstrate how economic development and environmental protection can be coordinated. There are three main reasons for contributing to this coordinated development: 1) the unique geomorphologic features of Poyang Lake and the short water residence time; 2) the matching of the basin physical boundary with the administrative boundary; and 3) the implementation of "Mountain-River-Lake Program" (MRL), with the ecosystem concept of "mountain as source, river as connection flow, and lake as storage". In addition, a series of actions have been taken to coordinate development, utilisation, management and protection in the Poyang Lake basin. Our key experiences are: considering all basin components when focusing on lake environment protection is a guiding principle; raising the living standard of people through implementation of various eco-economic projects or models in the basin is the most important strategy; preventing soil and water erosion is critical for protecting water sources; and establishing an effective governance mechanism for basin management is essential. This successful, large-scale basin management model can be extended to any basin or lake regions of developing countries where both environmental protection and economic development are needed and coordinated.

  10. 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.

  11. Orocline-driven transtensional basins: Insights from the Lower Permian Manning Basin (eastern Australia)

    NASA Astrophysics Data System (ADS)

    White, Llyam; Rosenbaum, Gideon; Allen, Charlotte M.; Shaanan, Uri

    2016-03-01

    The New England Orogen in eastern Australia exhibits an oroclinal structure, but its geometry and geodynamic evolution are controversial. Here we present new data from the southernmost part of the oroclinal structure, the Manning Orocline, which supposedly developed in the Early Permian, contemporaneously and/or shortly after the deposition of the Lower Permian Manning Basin. New U-Pb detrital zircon data provide a maximum depositional age of ~288 Ma. Structural evidence from rocks of the Manning Basin indicates that both bedding and preoroclinal fold axial planes are approximately oriented parallel to the trace of the Manning Orocline. Brittle deformation was dominated by sinistral strike-slip faulting, particularly along a major fault zone (Peel-Manning Fault System), which is marked by the occurrence of a serpentinitic mélange, and separates tectonostratigraphic units of the New England Orogen. Our revised geological map shows that the Manning Basin is bounded by faults and serpentinites, thus indicating that basin formation was intimately linked to deformation along the Peel-Manning Fault System. The Manning Basin is thus interpreted to be a transtensional pull-apart basin associated with the Peel-Manning Fault System. Age constraints and structural relationships indicate that basin formation likely occurred during the incipient stage of oroclinal bending, with block rotations and fragmentation of the transtensional pull-apart system occurring subsequently. The intimate link between oroclinal bending and basin formation in the New England oroclines indicates that back-arc extension, accompanied by transtensional deformation, could have played an important role in the early stage of orocline development.

  12. Tritium hydrology of the Mississippi River basin

    USGS Publications Warehouse

    Michel, R.L.

    2004-01-01

    In the early 1960s, the US Geological Survey began routinely analysing river water samples for tritium concentrations at locations within the Mississippi River basin. The sites included the main stem of the Mississippi River (at Luling Ferry, Louisiana), and three of its major tributaries, the Ohio River (at Markland Dam, Kentucky), the upper Missouri River (at Nebraska City, Nebraska) and the Arkansas River (near Van Buren, Arkansas). The measurements cover the period during the peak of the bomb-produced tritium transient when tritium concentrations in precipitation rose above natural levels by two to three orders of magnitude. Using measurements of tritium concentrations in precipitation, a tritium input function was established for the river basins above the Ohio River, Missouri River and Arkansas River sampling locations. Owing to the extent of the basin above the Luling Ferry site, no input function was developed for that location. The input functions for the Ohio and Missouri Rivers were then used in a two-component mixing model to estimate residence times of water within these two basins. (The Arkansas River was not modelled because of extremely large yearly variations in flow during the peak of the tritium transient.) The two components used were: (i) recent precipitation (prompt outflow) and (ii) waters derived from the long-term groundwater reservoir of the basin. The tritium concentration of the second component is a function of the atmospheric input and the residence times of the groundwaters within the basin. Using yearly time periods, the parameters of the model were varied until a best fit was obtained between modelled and measured tritium data. The results from the model indicate that about 40% of the flow in the Ohio River was from prompt outflow, as compared with 10% for the Missouri River. Mean residence times of 10 years were calculated for the groundwater component of the Ohio River versus 4 years for the Missouri River. The mass flux of

  13. Modeling Nitrogen Losses under Rapid Infiltration Basins

    NASA Astrophysics Data System (ADS)

    Akhavan, M.; Imhoff, P. T.; Andres, A. S.; Finsterle, S.

    2011-12-01

    Rapid Infiltration Basin System (RIBS) is one of the major land treatment techniques used for wastewater treatment and reuse of recovered treated wastewater. In this system, wastewater that is treated using primary, secondary, or advanced treatment techniques is applied at high rates to shallow basins constructed in permeable deposits of soil or sand, with further treatment occurring in soil and the vadose zone before the water recharges groundwater. Because the influent wastewater is usually enriched in nitrogen (N) compounds, there is particular concern that RIBS may contaminant groundwater or nearby surface waters if not designed and operated properly. In most of the new sequenced batch reactor (SBR) wastewater treatment plants, N is found in the form of nitrate in the discharged wastewater, so denitrification (DNF) is the main reaction in N removal. The absence of molecular oxygen is one of the required conditions for DNF. During RIBS operation, application of wastewater is cyclic and typically consists of a flooding period followed by days or weeks of drying. Key operational parameters include the ratio of wetting to drying time and the hydraulic loading rate, which affect water saturation and air content in the vadose zone and as a result have an impact on DNF. Wastewater is typically distributed at a limited number of discharge points in RIBS and basins are not usually completely flooded which result in non-homogeneous distribution of wastewater and unusual surface water flow patterns. For this reason, we couple overland flow within RIBS with subsurface flow to investigate the influence of non-uniform application of wastewater on DNF. No modeling effort has been done for understanding this aspect of RIBS performance previously. TOUGH2/ iTOUGH2, a general-purpose numerical simulation program for multi-phase fluid flow in porous media, is used for modeling fluid movement. Water saturation is used as a surrogate parameter to evaluate oxygen limitations in the

  14. K Basin sludge dissolution engineering study

    SciTech Connect

    Westra, A.G.

    1998-08-28

    The purpose of this engineering study is to investigate the available technology related to dissolution of the K Basin sludge in nitric acid. The conclusion of this study along with laboratory and hot cell tests with actual sludge samples will provide the basis for beginning conceptual design of the sludge dissolver. The K Basin sludge contains uranium oxides, fragments of metallic U, and some U hydride as well as ferric oxyhydroxide, aluminum oxides and hydroxides, windblown sand that infiltrated the basin enclosure, ion exchange resin, and miscellaneous materials. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be conditioned so that it meets Tank Waste Remediation System waste acceptance criteria and can be sent to one of the underground storage tanks. Sludge conditioning will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and then reacting the solution with caustic to co-precipitate the uranium and plutonium. There will be five distinct feed streams to the sludge conditioning process two from the K East (KE) Basin and three from the K West (KW) Basin. The composition of the floor and pit sludges which contain more iron oxides and sand than uranium is much different than the canister sludges which are composed of mostly uranium oxides. The sludge conditioning equipment will be designed to process all of the sludge streams, but some of the operating parameters will be adjusted as necessary to handle the different sludge stream compositions. The volume of chemical additions and the amount of undissolved solids will be much different for floor and pit sludge than for canister sludge. Dissolution of uranium metal and uranium dioxide has been studied quite thoroughly and much information is available. Both uranium metal and uranium dioxide have been dissolved on a large scale in nuclear fuel

  15. Rift basins in western margin of India and their hydrocarbon prospects with special reference to Kutch basin

    SciTech Connect

    Biswas, S.K.

    1982-10-01

    The western continental margin of India can be classed as a divergent or passive margin. The western continental shelf is an extensive carbonate bank (Bombay offshore basin) passing into clastic sediments on the north and south. Three craton-margin embayed basins-Kutch, Cambay, and Narmada- in the northern part of the shelf, are filled predominantly with clastic sediments. These basins occupy grabens bounded by faults diverging seaward. The grabens were formed by three rift systems along major Precambrian tectonic trends. The rifting developed sequentially from north to south around the Saurashtra horst. Kutch basin was formed in the Early Jurassic, followed by Cambay basin in Early Cretaceous time, and the Narmada in the Late Cretaceous. It appears that these rifting events occurred at successive stages during the northward migration of the Indian plate after its break from Gondwanaland in Late Triassic or Early Jurassic. It is inferred that these rift basins opened up successively as a result of the counterclockwise drift of the Indian craton. Bombay offshore and Cambay are two major oil-producing basins in the western margin. These basins are characterized by high geothermal gradients attributed to the shallowness of the mantle in this region. Oil has not been found in KUtch basin, which is mainly an onshore Mesozoic basin. The basin basin depocenter shifted offshore at the northwestern part of the continental shelf where the shelf is wide.

  16. Massive Impact Craters and Basins on Earth: Regarding the Amazon as a 3500 km Multi Ring Impact Basin

    NASA Astrophysics Data System (ADS)

    Burgener, J. A.

    2013-09-01

    The Amazon Basin is a multi-ring impact basin. The center has a 500 km diameter layer of ocean basalt. Surrounding and below is intermixed sediments and melt rock. The topography fits the same pattern as the Lunar Orientale Basin.

  17. Pennsylvanian-Permian tectonism in the Great Basin: The Dry Mountain trough and related basins

    SciTech Connect

    Snyder, W.S.; Spinosa, C.; Gallegos, D.M. )

    1991-02-01

    Pennsylvanian-Permian tectonism affected the continental margin of western North America from the Yukon to the Mojave Desert. Specific signatures of this tectonism include local angular unconformities, regional disconformities, renewed outpouring of clastic debris from a reactivated Antler and related highlands, and development of deeper water basins with anoxic sediments deposited below wave base. The basins formed include Ishbel trough (Canada), the Wood River basin (Idaho), Cassia basin, Ferguson trough, Dry Mountain trough (all Nevada), and unnamed basins in Death Valley-Mojave Desert region. The Dry Mountain trough (DMT) was initiated during early Wolfcampian and received up to 1,200 m of sediment by the late Leonardian. The lower contact is a regional unconformity with the Ely Limestone, or locally with the Diamond Peak or Vinini formations. Thus, following a period of localized regional uplift that destroyed the Ely basin, portions of the uplifted and exposed shelf subsided creating the Dry Mountain trough. Evidence suggesting a tectonic origin for the DMT includes (1) high subsidence rates (60-140 m/m.y.); (2) renewed influx of coarse clastic debris from the Antler highlands: (3) possible pre-Early Permian folding, thrusting, and tilting within the highlands; and (4) differential subsidence within the Dry Mountain trough, suggesting the existence of independent fault blocks.

  18. Gravity-driven structures and rift basin evolution: Rio Muni Basin, offshore equatorial West Africa

    SciTech Connect

    Turner, J.P.

    1995-08-01

    Offshore Equatorial Guinea, west Africa, gravity-driven nappes, more than 1 km thick and 15 km from head to toe, provide key evidence in reconstructing the late synrift: evolution of this part of the South Atlantic margin basin system. Furthermore, Aptian-Cenomanian carbonate and clastic rocks in the nappes` allochthonous hanging walls are attracting interest as a new exploration play in west Africa. The nappes exhibit a range of geometries that suggest they share many of the same deformation processes as thin-skin thrust and linked extensional fault systems. Not only are these structures significant in their own right, representing a rare example of gravity tectonics in the virtual absence of major halokinesis, but their presence may record an other-wise undetectable process active during the transition from a rift basin to a passive continental margin. A review of Equatorial Guinea in its pre-Atlantic configuration, alongside neighboring basins in Brazil (the Sergipe-Alagoas basin) and Gabon, suggests that gravity gliding was sustained by a relatively steep, westward paleoslope promoted by east-ward offset of the locus of thermal uplift from the rift basin (i.e., a simple shear model of basin formation). In contrast to gravity-driven structures in most postrift settings, the Equatorial Guinea nappes developed at the close of the Aptian-Albian synrift episode in response to a growing bathymetric deep caused by rapid subsidence outpacing restricted sedimentation.

  19. Water Temperature Controls in Arctic Basins

    NASA Astrophysics Data System (ADS)

    Neilson, B. T.; King, T.; Schmadel, N. M.; Heavilin, J.; Overbeck, L. D.; Kane, D. L.

    2015-12-01

    Understanding the dynamics of heat transfer mechanisms in arctic rivers is critical for forecasting the effects of climate change on river temperatures. Building on the collection of key data and a dynamic river temperature model that accounts for heat fluxes found important in temperate climates, we were able to identify portions of an arctic basin and hydrologic conditions for which heat flux dynamics differ from those found in temperate systems. During the open water season, similarities in heat flux influences include dominant shortwave radiation, greater surface exchanges than bed exchanges and greater influences of lateral inflows in the lower order portions of the basin. Differing from temperate systems, the heat flux contribution of net longwave radiation is consistently negative and both latent heat and bed friction are negligible. Despite these differences, accounting for the bulk lateral inflows from the basin resulted in accurate predictions during higher flows. Under lower flow conditions, however, lateral inflows were limited and resulting temperature predictions were poor. Work in a temperate system demonstrated that spatial variability in hydraulics influencing stream residence times are necessary for accurate river temperature predictions. Because heat fluxes at the air-water interface become increasingly dominant at low flows and these fluxes are sensitive to parameters representing the water surface area to volume ratio, similar to temperate systems, we expect that high-resolution representations of stream geometry and hydraulics are important both for accurate flux and residence time estimates. Furthermore, given the highly dynamic nature of flows in arctic basins, we anticipate that detailed information regarding spatially variable hydraulic characteristics (e.g., channel width, depth, and velocity) is critical for accurate predictions in low arctic rivers through a large range of flow conditions. Upon identifying key processes controlling

  20. Okanogan Basin Spring Spawner Report for 2007.

    SciTech Connect

    Colville Tribes, Department of Fish & Wildlife

    2007-09-01

    The Okanogan Basin Monitoring and Evaluation Program collected data related to spring spawning anadromous salmonid stocks across the entire Okanogan River basin. Data were collected using redd surveys, traps, underwater video, and PIT-tag technology then summarized and analyzed using simple estimate models. From these efforts we estimated that 1,266 summer steelhead spawned in the Okanogan River basin and constructed 552 redds;152 of these fish where of natural origin. Of these, 121 summer steelhead, including 29 of natural origin, created an estimated 70 redds in the Canadian portion of the Okanagan basin. We estimated summer steelhead spawner escapement into each sub-watershed along with the number from natural origin and the number and density of redds. We documented redd desiccation in Loup Loup Creek, habitat utilization in Salmon Creek as a result of a new water lease program, and 10 spring Chinook returning to Omak Creek. High water through most of the redd survey period resulted in development of new modeling techniques and allowed us to survey additional tributaries including the observation of summer steelhead spawning in Wanacut Creek. These 2007 data provide additional support that redd surveys conducted within the United States are well founded and provide essential information for tracking the recovery of listed summer steelhead. Conversely, redd surveys do not appear to be the best approach for enumerating steelhead spawners or there distribution within Canada. We also identified that spawning distributions within the Okanogan River basin vary widely and stocking location may play an over riding roll in this variability.

  1. Basin analysis of South Mozambique graben

    SciTech Connect

    Iliffe, J.; Lerche, I.; De Buyl, M.

    1987-05-01

    Basin analysis of the South Mozambique graben between latitudes 25/sup 0/ and 26/sup 0/ and longitudes 34/sup 0/ and 35/sup 0/ demonstrates how modeling techniques may help to assess the oil potential of a speculative basin with only minimal seismic data. Two-dimensional restoration of the seismic profiles, using a backstripping and decompaction program on pseudowells linked with structural reconstruction, assesses the rift's two-phase extensional history. Since no well or thermal indicator data exist within the basin, the thermal history had to be derived from extensional models. The best fit of observed subsidence curves and those predicted by the models results in values of lithospheric extension (gamma). The disagreement in observed and theoretical basement subsidence curves was minimized by taking a range of gamma for each model for each well. These extension factors were then used in each model's equations for paleoheat flux to derive the heat-flow histories. (It is noted that a systematic basinwide variance of gamma occurs.) The heat-flux histories were then used with a one-dimensional fluid flow/compaction model to calculate TTI values and oil windows. A Tissot generation model was applied to each formation in every well for kerogen Types I, II, and III. The results were contoured across the basin to assess possible oil- and gas-prone formations. The extensional, burial, and thermal histories are integrated into an overall basin development picture and provide an oil and gas provenance model. Thus they estimate the basinwide hydrocarbon potential and also gain insight into the additional data necessary to significantly decrease the uncertainty.

  2. Magmatism in rifting and basin formation

    NASA Astrophysics Data System (ADS)

    Thybo, H.

    2008-12-01

    Whether heating and magmatism cause rifting or rifting processes cause magmatic activity is highly debated. The stretching factor in rift zones can be estimated as the relation between the initial and the final crustal thickness provided that the magmatic addition to the crust is insignificant. Recent research demonstrates substantial magmatic intrusion into the crust in the form of sill like structures in the lowest crust in the presently active Kenya and Baikal rift zones and the DonBas palaeo-rift zone in Ukraine. This result may be surprising as the Kenya Rift is associated with large amounts of volcanic products, whereas the Baikal Rift shows very little volcanism. Identification of large amounts of magmatic intrusion into the crust has strong implications for estimation of stretching factor, which in the case of Baikal Rift Zone is around 1.7 but direct estimation gives a value of 1.3-1.4 if the magmatic addition is not taken into account. This may indicate that much more stretching has taken place on rift systems than hitherto believed. Wide sedimentary basins may form around aborted rifts due to loading of the lithosphere by sedimentary and volcanic in-fill of the rift. This type of subsidence will create wide basins without faulting. The Norwegian- Danish basin in the North Sea area also has subsided gradually during the Triassic without faulting, but only few rift structures have been identified below the Triassic sequences. We have identified several mafic intrusions in the form of large batholiths, typically more than 100 km long, 20-40 km wide and 20 km thick. The associated heating would have lifted the surface by about 2 km, which may have been eroded before cooling. The subsequent contraction due to solidification and cooling would create subsidence in a geometry similar to basins that developed by loading. These new aspects of magmatism will be discussed with regard to rifting and basin formation.

  3. Basic cytogenetics and physical mapping of 5S and 18S ribosomal genes in Hoplias malabaricus (Osteichthyes, Characiformes, Erythrinidae) from isolated natural lagoons: a conserved karyomorph along the Iguaçu river basin.

    PubMed

    Gemi, Gisele; Lui, Roberto Laridondo; Treco, Fernando Rodrigo; Paiz, Leonardo Marcel; Moresco, Rafaela Maria; Margarido, Vladimir Pavan

    2014-01-01

    Erythrinidae include Neotropical teleost fish that are widely distributed in South America. Hoplias Gill, 1903 include two large groups: H. malabaricus Bloch, 1794 and H. lacerdae Miranda Ribeiro, 1908. Hoplias malabaricus is characterized by remarkable karyotype diversity, with some karyomorphs widely distributed geographically while others are more restricted to certain river basins. Cytogenetic analyzes were performed in a population of Hoplias malabaricus from the Wildlife Refuge of Campos de Palmas, the Iguaçu River basin. The specimens showed diploid number of 42 chromosomes (24m+18sm) without differentiated sex chromosomes system. The impregnation by silver nitrate showed multiple AgNORs. Seven pairs (4, 7, 10, 13, 16, 20 and 21) carrying 18S rDNA were detected by FISH. Heterochromatin was verified in the centromeric and pericentromeric region of most chromosomes and the terminal region of some pairs. FISH with 5S rDNA probes showed two chromosome pairs carrying these sites in the interstitial region (8 and 14). The data obtained in this study are similar to those found for two other populations of H. malabaricus already studied in the basin of the Iguaçu River, confirming the hypothesis that this species is natural, not having been introduced, as well as having an intrinsic characteristic, such as the largest number of sites of 18S rDNA.

  4. South Platte River Basin - Colorado, Nebraska, and Wyoming

    USGS Publications Warehouse

    Dennehy, Keuin F.; Litke, David W.; Tate, Cathy M.; Heiny, Janet S.

    1993-01-01

    The South Platte River Basin was one of 20 study units selected in 1991 for investigation under the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) program. One of the initial tasks undertaken by the study unit team was to review the environmental setting of the basin and assemble ancillary data on natural and anthropogenic factors in the basin. The physical, chemical, and biological quality of the water in the South Platte River Basin is explicitly tied to its environmental setting. The resulting water quality is the product of the natural conditions and human factors that make up the environmental setting of the basin.

  5. The evolution of impact basins - Cooling, subsidence, and thermal stress

    NASA Technical Reports Server (NTRS)

    Bratt, S. R.; Solomon, S. C.; Head, J. W.

    1985-01-01

    The present study is concerned with an assessment of the contribution of thermal contraction and thermal stress to the topography and tectonics of large lunar impact basins. Exploratory models are developed, giving attention to the temperature structure following basin formation, the subsequent cooling of the basin region, and the resulting thermal displacements and stresses as functions of time. The subsidence and stress at the surface are compared with topography and tectonic features in the comparatively well-preserved Orientale basin. The results of the comparison are used as a basis to derive approximate constraints on the quantity and distribution of heat implanted during the basin-formation process.

  6. Numerical modelling of ground motion in the Taipei Basin: basin and source effects

    NASA Astrophysics Data System (ADS)

    Miksat, J.; Wen, K.-L.; Wenzel, F.; Sokolov, V.; Chen, C.-T.

    2010-12-01

    The Taipei basin in northern Taiwan is located in a high seismicity region and was affected by several earthquakes in the past (ML = 7.3 on 1909 April 15; ML = 6.8 on 1986 November 15; the Chi-Chi ML = 7.3 earthquake on 1999 September 21 and ML = 6.8 on 2002 March 31). The main characteristic of the Taipei basin is its complex shape with a deep western and shallow eastern part. The uppermost Sungshan formation with its low shear wave velocities (90-200ms-1) is also a distinct feature of the basin. Based on the large data base of earthquake records obtained from the Taiwan Strong Motion Instrumentation Program network, many studies on ground motion within the Taipei basin exist. However, the influence of the various subsurface structures on the observed ground motions as well as the variability of ground motion with respect to earthquake location is not fully understood. We apply a 3-D finite-difference method to simulate wave propagation up to 1Hz for a small earthquake close to the basin in order to resolve these open questions. By varying source and structural parameters, we explore the variability of ground motion. Our study includes a subsurface model that is based on recent studies on the basin structure and on the crustal structure of Taiwan. From our simulations we find a good fit between simulated and observed waveforms and peak ground accelerations for the considered small earthquake near the basin. We also explore the influence of fault plane orientation, hypocentre location, deep basin structure and soft soil surface layers of the Sungshan formation by varying the subsurface structure and earthquake position. Our studies reveal that the basin structure produces an amplification factor of about 4 compared to hard rock conditions. Additionally, the soft soil Sungshan formation produce amplification of a factor of 2. This results in a maximum amplification of the basin structure of about 8, which is in good comparison with amplification values larger than 5

  7. Ghaba salt basin province and Fahud salt basin province, Oman; geological overview and total petroleum systems

    USGS Publications Warehouse

    Pollastro, R.M.

    1999-01-01

    Three Total Petroleum Systems each consisting of one assessment unit have been identified in the Ghaba and Fahud Salt Basin Provinces of north-central Oman. One Total Petroleum System and corresponding assessment unit, the North Oman Huqf/`Q'? Haushi(!) Total Petroleum System (201401) and Ghaba-Makarem Combined Structural Assessment Unit (20140101), were identified for the Ghaba Salt Basin Province (2014). In the Fahud Salt Basin Province, however, two overlapping Total Petroleum Systems (TPS) were recognized: 1) the North Oman Huqf ? Shu'aiba(!) TPS (201601); Fahud-Huqf Combined Structural Assessment Unit (20160101), and 2) the Middle Cretaceous Natih(!) TPS (201602); Natih-Fiqa Structural/Stratigraphic Assessment Unit (20160201). The boundary for each Total Petroleum System also defines the boundary of the corresponding assessment unit and includes all trap styles and hydrocarbon producing reservoirs within the petroleum system. In both the Ghaba and Fahud Salt Basin Provinces, hydrocarbons were generated from several deeply-buried source rocks within the Infracambrian Huqf Supergroup. One general `North Oman Huqf' type oil is dominant in the Fahud Salt Basin. Oils in the Ghaba Salt Basin are linked to at least two distinct Huqf source-rock units based on oil geochemistry: a general North Oman Huqf-type oil source and a more dominant `questionable unidentified-source' or `Q'-type Huqf oil source. These two Huqf-sourced oils are commonly found as admixtures in reservoirs throughout north-central Oman. Hydrocarbons generated from Huqf sources are produced from a variety of reservoir types and ages ranging from Precambrian to Cretaceous in both the Ghaba and Fahud Salt Basin Provinces. Clastic reservoirs of the Gharif and Al Khlata Formations, Haushi Group (M. Carboniferous to L. Permian), dominate oil production in the Ghaba Salt Basin Province and form the basis for the Huqf/`Q' ? Haushi(!) TPS. In contrast, the Lower Cretaceous Shu'aiba and Middle Cretaceous

  8. Petroleum prospectivity in Precambrian and Early Paleozoic basins, Australia

    SciTech Connect

    Goldstein, B.A. )

    1991-03-01

    Proterozoic to Devonian age strata with some potential for petroleum accumulations are known from sedimentary basins covering {approximately}1,870,000 km{sup 2} onshore Australia. Portions of these very old basins have not sustained the deleterious effects of deep burial. Explorers with vision continue to target these very old rocks in the MacArthur/South Nicholson, Amadeus, Canning, Adavale, and Bonaparte basins. Approximately 429,000 km{sup 2} of these basins remain under license for petroleum exploration. The oldest known oil in Australia is reservoired within and sourced from the mid-Proterozoic in the McArthur basin. The Early Ordovician Pacoota Sandstone of the Amadeus basin is the oldest formation commercially exploited for oil and gas in Australia. Significant discoveries awaiting development include Dingo, Pictor, and Gilmore. The Tern gas field trap in the Bonaparte basin is related to a salt diapir; the salt probably being Silurian-Devonian in age. Salt probably of the same age has formed diapirs in the Canning basin, too. Cambrian and Proterozoic salt-bearing strata are likewise the cause and core of some anticlinal and diapiric structures in the Amadeus basin. Minor oil shows have been reported from the Cambrian of the Officer basin. The Warburton, Pedirka, Arrowie, Ord, Wiso, Georgina, and Ngalia basins contain Proterozoic and early Paleozoic sedimentary rocks but are ascribed only limited petroleum prospectivity at this time.

  9. Hydrocarbon potential of early mesozoic basins of eastern United States

    SciTech Connect

    Schlamel, S.

    1988-01-01

    The exposed Triassic-Liassic rift basins in the eastern United States are half-grabens filled with up to 7 km of continental sediments. The location and sense of asymmetry of the half-grabens are closely tied to the structural grain of the Appalachian crystalline terranes on which they have formed. In many instances, the faulted margins of the basins are older thrusts or terrane boundaries reactivated as listric normal faults. The sediment fill of the basins reflects their structural asymmetry. Coarse alluvial fan deposits along the main border faults pass basinward into a complex assemblage of fluvial, paludal, and lacustrine facies. The oldest sediment fill in the rift basins is dated palynologically as late Ladinian to late Carnian. Perhaps reflecting the northward opening of the central Atlantic, the youngest rift-fill sediments are older in the southern basins than in the northern-Carnian in the Righmond basin vs. Toarcian in the Hartford-Deerfield basin. Floral evidence points to a tropical to near-tropical environment, with severe oscillations between xerophytic (dry) and hydrophytic (wet) conditions. The degree of thermal maturation, as estimated from vitrinite reflectance and clay mineralogy, varies widely from basin to basin; however, most of the basins are within the oil to dry gas generative window. The basins with highest thermal maturities are those having large volumes of diabase intrusives and presumed higher paleogeothermal gradients. The peak of thermal maturation/migration may have occurred as early as the Jurassic.

  10. Archean foreland basin tectonics from the Witwatersrand, South Africa

    SciTech Connect

    Burke, K.; Kidd, W.S.F.; Kusky, T.M.

    1985-01-01

    The Witwatersrand Basin of South Africa is the best-known of Archean sedimentary basins and contains some of the largest gold reserves in the world. Sediments in the basin include a lower flysch-type sequence and an upper molassic facies, both of which contain abundant silicic volcanic detritus. The strata are thicker and more proximal on the northwestern side of the basin which is, at least locally, bound by thrust faults. These and other features indicate that the Witwatersrand strata were deposited in a foreland basin. A regional geologic synthesis suggests that his basin developed initially on the cratonward side of an Andean-type arc. Remarkably similar Phanerozoic basins may be found in the southern Andes above zones of shallow subduction. We suggest that the continental collision between the Kaapvaal and Zimbabwe Cratons at about 2.7 Ga caused further subsidence and deposition in the Witwatersrand Basin. Regional uplift during this later phase of development placed the basin on the cratonward edge of a collision-related plateau, now represented by the Limpopo Province. Striking similarities are seen between this phase of Witwatersrand Basin evolution and active basins located north of the Tibetan Plateau. The geologic evidence is not so compatible with earlier suggestions that the Witwatersrand strata were deposited in a rift or half-graben.

  11. Archean foreland basin tectonics in the Witwatersrand, South Africa

    SciTech Connect

    Burke, K.; Kidd, W.S.F.; Kusky, T.M.

    1986-06-01

    The Witwatersrand Basin of South Africa is the best-known of Archean sedimentary basins and contains some of the largest gold reserves in the world. Sediments in the basin include a lower flysch-type sequence and an upper molassic facies, both of which contain abundant silicic volcanic detritus. The strata are thicker and more proximal on the northwestern side of the basin which is, at least locally, bound by thrust faults. These features indicate that the Witwatersrand strata may have been deposited in a foreland basin and a regional geologic synthesis suggests that this basin developed initially on the cratonward side of an Andean-type arc. Remarkably similar Phanerozoic basins may be found in the southern Andes above zones of shallow subduction. It is suggested that the continental collision between the Kaapvaal and Zimbabwe Cratons at about 2.7 Ga caused further subsidence and deposition in the Witwatersrand Basin. Regional uplift during this later phase of development placed the basin on the cratonward edge of a collision-related plateau, now represented by the Limpopo Province. Similarities are seen between this Phase of Witywatersrand Basin evolution and that of active basins north of the Tibetan Plateau. The geologic evidence does not agree with earlier suggestions that the Witwatersrand strata were deposited in a rift or half-graben. 64 references.

  12. Archean foreland basin tectonics in the Witwatersrand, South Africa

    NASA Technical Reports Server (NTRS)

    Burke, K.; Kidd, W. S. F.; Kusky, T. M.

    1986-01-01

    The Witwatersrand Basin of South Africa is the best-known of Archean sedimentary basins and contains some of the largest gold reserves in the world. Sediments in the basin include a lower flysch-type sequence and an upper molassic facies, both of which contain abundant silicic volcanic detritus. The strata are thicker and more proximal on the northwestern side of the basin which is, at least locally, bound by thrust faults. These features indicate that the Witwatersrand strata may have been deposited in a foreland basin and a regional geologic synthesis suggests that this basin developed initially on the cratonward side of an Andean-type arc. Remarkably similar Phanerozoic basins may be found in the southern Andes above zones of shallow subduction. It is suggested that the continental collision between the Kaapvaal and Zimbabwe Cratons at about 2.7 Ga caused further subsidence and deposition in the Witwatersrand Basin. Regional uplift during this later phase of development placed the basin on the cratonward edge of a collision-related plateau, now represented by the Limpopo Province. Similarities are seen between this Phase of Witywatersrand Basin evolution and that of active basins north of the Tibetan Plateau. The geologic evidence does not agree with earlier suggestions that the Witwatersrand strata were deposited in a rift or half-graben.

  13. Archean foreland basin tectonics in the Witwatersrand, South Africa

    NASA Technical Reports Server (NTRS)

    Burke, K.; Kidd, W. S. F.; Kusky, T. M.

    1986-01-01

    The Witwatersrand Basin of South Africa is the best-known of Archean sedimentary basins and contains some of the largest gold reserves in the world. Sediments in the basin include a lower flysch-type sequence and an upper molassic facies, both of which contain abundant silicic volcanic detritus. The strata are thicker and more proximal on the northwestern side of the basin which is, at least locally, bound by thrust faults. These features indicate that the Witwatersrand strata may have been deposited in a foreland basin and a regional geologic synthesis suggests that this basin developed initially on the cratonward side of an Andean-type arc. Remarkably similar Phanerozoic basins may be found in the southern Andes above zones of shallow subduction. It is suggested that the continental collision between the Kaapvaal and Zimbabwe Cratons at about 2.7 Ga caused further subsidence and deposition in the Witwatersrand Basin. Regional uplift during this later phase of development placed the basin on the cratonward edge of a collision-related plateau, now represented by the Limpopo Province. Similarities are seen between this phase of Witwatersrand Basin evolution and that of active basins north of the Tibetan Plateau. The geologic evidence does not agree with earlier suggestions that the Witwatersrand strata were deposited in a rift or half-graben.

  14. Distribution, Statistics, and Resurfacing of Large Impact Basins on Mercury

    NASA Technical Reports Server (NTRS)

    Fassett, Caleb I.; Head, James W.; Baker, David M. H.; Chapman, Clark R.; Murchie, Scott L.; Neumann, Gregory A.; Oberst, Juergen; Prockter, Louise M.; Smith, David E.; Solomon, Sean C.; Strom, Robert G.; Xiao, Zhiyong; Zuber, Maria T.

    2012-01-01

    The distribution and geological history of large impact basins (diameter D greater than or equal to 300 km) on Mercury is important to understanding the planet's stratigraphy and surface evolution. It is also informative to compare the density of impact basins on Mercury with that of the Moon to understand similarities and differences in their impact crater and basin populations [1, 2]. A variety of impact basins were proposed on the basis of geological mapping with Mariner 10 data [e.g. 3]. This basin population can now be re-assessed and extended to the full planet, using data from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Note that small-to- medium-sized peak-ring basins on Mercury are being examined separately [4, 5]; only the three largest peak-ring basins on Mercury overlap with the size range we consider here. In this study, we (1) re-examine the large basins suggested on the basis of Mariner 10 data, (2) suggest additional basins from MESSENGER's global coverage of Mercury, (3) assess the size-frequency distribution of mercurian basins on the basis of these global observations and compare it to the Moon, and (4) analyze the implications of these observations for the modification history of basins on Mercury.

  15. Anomalous wave propagation across the South Caspian Basin

    SciTech Connect

    Priestly, K.; Patton, H.J.; Schultz, C.

    1997-10-01

    The Caspian basin blocks the propagation of the regional seismic phase Lg and this has importance consequences for seismic discrimination in the Middle East. Intermediate period surface waves propagating across the basin are also severely affected. In a separate study we have developed a crustal model of the south Caspian basin and the surrounding region. The crust of the basin consists of 15-25 km of low velocity, highly attenuating sediments lying on high velocity crystalline crust. The Moho beneath the basin is at a depth of about 30 km as compared to about 50 km in the surrounding region. In this study we used an idealized rendition of this crustal model to compute hybrid normal mode finite difference synthetic seismograms to identify the features of the Caspian basin which lead to the seismic blockage. Of the various features of the basin, the thickness and attenuation of the sediments appear to be the dominant blocking mechanism.

  16. Propagation of seismic ground motion in the Kanto Basin, Japan.

    PubMed

    Koketsu, K; Kikuchi, M

    2000-05-19

    The pattern of ground motion for a magnitude 5.7 earthquake near Tokyo was captured by 384 strong ground motion instruments across the Kanto sedimentary basin and its surroundings. The records allow the visualization of the propagation of long-period ground motion in the basin and show the refraction of surface waves at the basin edge. The refracted wave does not travel directly from the earthquake epicenter, but traverses the basin obliquely to the edge. The surface wave inside the basin propagates more slowly than that outside such that the wavefronts separate from each other, and the refracted wave heals the discrepancy in the speed of advance of the wavefronts inside and outside the basin. The refracted arrival is dominant near the edge of the Kanto basin.

  17. Evolution of the Rembrandt impact basin on Mercury.

    PubMed

    Watters, Thomas R; Head, James W; Solomon, Sean C; Robinson, Mark S; Chapman, Clark R; Denevi, Brett W; Fassett, Caleb I; Murchie, Scott L; Strom, Robert G

    2009-05-01

    MESSENGER's second Mercury flyby revealed a ~715-kilometer-diameter impact basin, the second-largest well-preserved basin-scale impact structure known on the planet. The Rembrandt basin is comparable in age to the Caloris basin, is partially flooded by volcanic plains, and displays a unique wheel-and-spoke-like pattern of basin-radial and basin-concentric wrinkle ridges and graben. Stratigraphic relations indicate a multistaged infilling and deformational history involving successive or overlapping phases of contractional and extensional deformation. The youngest deformation of the basin involved the formation of a approximately 1000-kilometer-long lobate scarp, a product of the global cooling and contraction of Mercury. PMID:19407197

  18. Stratigraphy and lithofacies of Foster formation in Michigan basin

    SciTech Connect

    Luneau, B.A.; Longman, M.W.; Horne, J.C. )

    1989-08-01

    The Lower Ordovician Foster formation lies in apparent conformity on the Umlor formation and is both conformably and unconformably overlain by the St. Peter Sandstone (Bruggers Formation), the primary target of the Michigan basin deep gas play. The Foster is stratigraphically equivalent to the Shakopee Dolomite and New Richmond Sandstone of the Illinois basin. The Foster formation is composed of up to 500 m of shallow marine and peritidal deposits divisible into three intervals. The basal interval is relatively uniform in thickness throughout the basin and is recognized by its interbedded lithologies above the relatively massive Unlor formation. The basal interval is primarily dolomite and sandstone with minor anhydrite. The middle interval is thickest in the basin center and progressively onlaps the basin margins. This interval is primarily dolomite and anhydrite. The upper unit extends throughout the basin but is thinner and truncated from above along the basin margins. Shaly dolomite and sandstone are the major lithologies.

  19. SUBSIDENCE, CRUSTAL STRUCTURE, AND THERMAL EVOLUTION OF GEORGES BANK BASIN.

    USGS Publications Warehouse

    Swift, B. Ann; Sawyer, D.S.; Grow, J.A.; Klitgord, Kim D.

    1987-01-01

    A geographical study of Georges Bank basin defines a deep crustal structure that is interpreted in terms of the basin's tectonic and thermal history. Gravity models along three basin cross sections delineate two zones of crustal thinning at the basement hinge zone and oceanic crustal margins. These two zones bound rift-stage crust (about 25 km thick) which underlies the central portion of the basin. Subsidence analysis of the basin, using data from multichannel seismic reflection lines and two COST wells, suggests a rifting and (uniform) extensional origin. Two-dimensional finite difference modeling of the basin defines a crustal structure that concurs with the gravity and subsidence studies. The resulting isotherms show no major changes in the thermal structure since the Late Jurassic. In some areas of the basin, temperature sufficient for oil generation are determined from maturation studies of Jurassic sediments. Hydrocarbon generation is questionable, however, because of the probable lack of proper and sufficient kerogen in the Jurassic deposits.

  20. Undiscovered petroleum of the Brazilian interior sag basins

    USGS Publications Warehouse

    Kingston, J.; Matzko, J.R.

    1995-01-01

    This paper focuses on the four large intracratonic (or interior) sag basins of Brazil: the Solimoes, Amazonas, Parnaiba, and Parana. The smaller Chaco basin also is discussed, although in less detail. The Dolimoes basin has the greatest initial estimated undiscovered reserves of oil (0.04 BBO), and the Parana basin has the greatest initial estimated undiscovered reserves of gas (5.08 TCFG). The most important plays in the Solimoes and structurally similar Amazonas basins are the fold and fault closures associated with the wrench systems found in the basins. The plays in the Parana basin are limited to possible structural traps linked to fault-associated closures, and possibly to some wrench-related features.

  1. Tectonic setting of Cretaceous basins on the NE Tibetan Plateau: Insights from the Jungong basin

    USGS Publications Warehouse

    Craddock, W.H.; Kirby, E.; Dewen, Z.; Jianhui, L.

    2012-01-01

    Quantifying the Cenozoic growth of high topography in the Indo-Asian collision zone remains challenging, due in part to significant shortening that occurred within Eurasia before collision. A growing body of evidence suggests that regions far removed from the suture zone experienced deformation before and during the early phases of Himalayan orogenesis. In the present-day north-eastern Tibetan Plateau, widespread deposits of Cretaceous sediment attest to significant basin formation; however, the tectonic setting of these basins remains enigmatic. We present a study of a regionally extensive network of sedimentary basins that are spatially associated with a system of SE-vergent thrust faults and are now exposed in the high ranges of the north-eastern corner of the Tibetan Plateau. We focus on a particularly well-exposed basin, located ~20km north of the Kunlun fault in the Anyemaqen Shan. The basin is filled by ~900m of alluvial sediments that become finer-grained away from the basin-bounding fault. Additionally, beds in the proximal footwall of the basin-bounding fault exhibit progressive, up-section shallowing and several intraformational unconformities which can be traced into correlative conformities in the distal part of the basin. The observations show sediment accumulated in the basin during fault motion. Regional constraints on the timing of sediment deposition are provided by both fossil assemblages from the Early Cretaceous, and by K-Ar dating of volcanic rocks that floor and cross-cut sedimentary fill. We argue that during the Cretaceous, the interior NE Tibetan Plateau experienced NW-SE contractional deformation similar to that documented throughout the Qinling-Dabie orogen to the east. The Songpan-Ganzi terrane apparently marked the southern limit of this deformation, such that it may have been a relatively rigid block in the Tibetan lithosphere, separating regions experiencing deformation north of the convergent Tethyan margin from regions deforming

  2. Hellas: A double-impact basin

    NASA Astrophysics Data System (ADS)

    Arkani-Hamed, J.

    2010-12-01

    With the major axis to minor axis ratio of about 1.3, Hellas is probably the most elliptical giant impact basin on Mars, even more elliptical than the basin fits to the northern lowland [1]. Because less than 4% of the impacts in the solar system have occurred at impact angles greater than 80o relative to the planet surface [2] Hellas is perceived to be formed by a single oblique impact at the first glance. Numerical simulations of oblique impacts have lead to contradictory conclusions. For 1 km size projectile the shape of a resulting crater is found indistinguishable from circle as long as the impact angle is greater than 30o [3], whereas for a putative planetary scale impact that has created the northern lowland the impact angle as high as 60 degrees fundamentally affects the ellipticity of the supergiant basin [4]. Despite these contradicting results the two numerical models are in agreement in that a single impact creates a single cavity characterized by a single bowel shape with a maximum depth located beneath the basin. The subsequent basin collapse, impact induced melt and later volcanism have resulted in a smooth floor of Hellas, to a point that the present topography does not provide any viable information about the structure of the excavated cavity. Unlike these surface processes, the mantle plug created in the process of isostatic uplift of the mantle, has likely been less modified. Based on this premise, I calculated the shape of the mantle plug beneath Hellas basin using MOLA surface topography [5] and most recent gravity field of Mars, MRO110B2 of Jet Propulsion Laboratory [6], assuming that the gravity field arises from the surface topography and the crust-mantle density contract associated with the mantle plug. Spherical harmonics coefficients of degree 2-20 are retained to suppress small scale features. The resulting crust-mantle boundary shows two distinct mantle plugs one at the northwest and the other at the southeast of the center of the basin

  3. Evolution of a trench-slope basin within the Cascadia subduction margin: the Neogene Humboldt Basin, California

    USGS Publications Warehouse

    McCrory, P.A.

    1995-01-01

    The Neogene Humboldt (Eel River) Basin is located along the north-eastern margin of the Pacific Ocean within the Cascadia subduction zone. This sedimentary basin originated near the base of the accretionary prism in post-Eocene time. Subduction processes since that time have elevated strata in the south-eastern portion of the basin above sea level. High-resolution chronostratigraphic data from the onshore portion of the Humboldt Basin enable correlation of time-equivalent lithofacies across the palaeomargin, reconstruction of slope-basin evolution, and preliminary delineation of climatic and tectonic influence on lithological variation. -from Author

  4. Lithospheric-scale centrifuge models of pull-apart basins

    NASA Astrophysics Data System (ADS)

    Corti, Giacomo; Dooley, Tim P.

    2015-11-01

    We present here the results of the first lithospheric-scale centrifuge models of pull-apart basins. The experiments simulate relative displacement of two lithospheric blocks along two offset master faults, with the presence of a weak zone in the offset area localising deformation during strike-slip displacement. Reproducing the entire lithosphere-asthenosphere system provides boundary conditions that are more realistic than the horizontal detachment in traditional 1 g experiments and thus provide a better approximation of the dynamic evolution of natural pull-apart basins. Model results show that local extension in the pull-apart basins is accommodated through development of oblique-slip faulting at the basin margins and cross-basin faults obliquely cutting the rift depression. As observed in previous modelling studies, our centrifuge experiments suggest that the angle of offset between the master fault segments is one of the most important parameters controlling the architecture of pull-apart basins: the basins are lozenge shaped in the case of underlapping master faults, lazy-Z shaped in case of neutral offset and rhomboidal shaped for overlapping master faults. Model cross sections show significant along-strike variations in basin morphology, with transition from narrow V- and U-shaped grabens to a more symmetric, boxlike geometry passing from the basin terminations to the basin centre; a flip in the dominance of the sidewall faults from one end of the basin to the other is observed in all models. These geometries are also typical of 1 g models and characterise several pull-apart basins worldwide. Our models show that the complex faulting in the upper brittle layer corresponds at depth to strong thinning of the ductile layer in the weak zone; a rise of the base of the lithosphere occurs beneath the basin, and maximum lithospheric thinning roughly corresponds to the areas of maximum surface subsidence (i.e., the basin depocentre).

  5. Accounting for Basin Effects Will Improve Seismic Risk Assessments

    NASA Astrophysics Data System (ADS)

    Magistrale, Harold

    2010-05-01

    A fundamental problem in assessing the seismic risk of properties and providing loss prevention solutions is determining the distribution, amplitude, frequency characteristics, and duration of strong ground motion from potential future earthquakes. This task is complicated by the strong effects that three-dimensional (3D) geologic structures, such as sediment-filled basins, have on ground shaking. Numerical studies of seismic wave propagation have shown that ground motions are amplified and have longer durations within basins, and there are observations of basin-edge-generated surface waves and of basin-focusing effects on ground motions. Further, basins typically host deep and/or soft unconsolidated soils that commonly experience enhanced ground motions. Evaluation of the seismic hazards and risks to the basin properties requires 3D numerical ground motion simulations to quantify the contributions of deep basin structure and shallow site conditions to ground motions. These simulations require 3D seismic velocity models. Here, we review these contributions as determined in a mature model of the Los Angeles, California, basin; introduce a new model of the Salt Lake City, Utah, basin; and report on preliminary ground motion simulations in the Salt Lake model. Both models consist of detailed, rule-based representations of the major populated sediment-filled basins, embedded in a 3D crust over a variable depth Moho, over upper mantle velocities. The basins are parameterized as a set of objects and rules implemented in a computer code that generates seismic velocities and density at any desired point. The shallow basin velocities are directly constrained by geotechnical borehole logs and detailed surface site response unit mapping based on surface geology and Vs30 measurements. Based on simulations of a suite of earthquakes in the Los Angeles basin model, Day et al. (2008) model the effect of sedimentary basin depth on long period (2 to 10 s) response spectra. They

  6. Geofluid Dynamics of Faulted Sedimentary Basins

    NASA Astrophysics Data System (ADS)

    Garven, G.; Jung, B.; Boles, J. R.

    2014-12-01

    Faults are known to affect basin-scale groundwater flow, and exert a profound control on petroleum migration/accumulation, the PVT-history of hydrothermal fluids, and the natural (submarine) seepage from offshore reservoirs. For example, in the Santa Barbara basin, measured gas flow data from a natural submarine seep area in the Santa Barbara Channel helps constrain fault permeability k ~ 30 millidarcys for the large-scale upward migration of methane-bearing formation fluids along one of the major fault zones. At another offshore site near Platform Holly, pressure-transducer time-series data from a 1.5 km deep exploration well in the South Ellwood Field demonstrate a strong ocean tidal component, due to vertical fault connectivity to the seafloor. Analytical solutions to the poroelastic flow equation can be used to extract both fault permeability and compressibility parameters, based on tidal-signal amplitude attenuation and phase shift at depth. These data have proven useful in constraining coupled hydrogeologic 2-D models for reactive flow and geomechanical deformation. In a similar vein, our studies of faults in the Los Angeles basin, suggest an important role for the natural retention of fluids along the Newport-Inglewood fault zone. Based on the estimates of fault permeability derived above, we have also constructed new two-dimensional numerical simulations to characterize large-scale multiphase flow in complex heterogeneous and anisotropic geologic profiles, such as the Los Angeles basin. The numerical model was developed in our lab at Tufts from scratch, and based on an IMPES-type algorithm for a finite element/volume mesh. This numerical approach allowed us model large differentials in fluid saturation and relative permeability, caused by complex geological heterogeneities associated with sedimentation and faulting. Our two-phase flow models also replicated the formation-scale patterns of petroleum accumulation associated with the basin margin, where deep

  7. The Messinian Evaporites in the Levantine Basin

    NASA Astrophysics Data System (ADS)

    Netzeband, G. L.; Huebscher, C. P.; Gajewski, D.

    2005-12-01

    The Levantine Basin in the Southeastern Mediterranean Sea is a world class site for studying the initial stages of salt tectonics. The deposition of the evaporites took place during the Messinian salinity crisis 5.9 - 5.3 Ma ago. About 2 km of halite, gypsum and anhydrite were deposited in the basin. The evaporite body is not uniformly transparent, but marked by several internal reflections. Between these reflections, the evaporites appear transparent. This leads to the conclusion that they represent different cycles of evaporite deposition, each with a succession of upper and lower evaporites. All of these internal reflections are differently folded and distorted, proving that the deformation was syn-depositional. Thrust angles of up to 14 degrees are observed. The sediment cover on top mainly originates from Nile sediments. Hence, the sediment thickness varies between about 400 m in the northern part of the basin over 1000 m near the shelf off Israel and Lebanon to almost 3000 m near the Nile Delta. A simple 1-D backstripping analysis reveals that this immense difference in sediment load is the driving force for salt migration. Hence, the main direction of salt movement is SSW-NNE, there has been no movement in E-W direction. The superposition of 'thin-skinned' tectonics and 'thick-skinned' tectonics is clearly visible in the Levantine Basin: At the Cyprus Arc, the convergence zone of Africa and Eurasia, deep-rooted compression heavily deformed the base of the salt, whereas at the Eratosthenes Seamount mainly superficial compression affecting the Post-Messinian sediments and the top of the evaporites is observed. Shear zones and fault lines, which have been postulated in the Levantine Basin, follow two trends: SSW-NNE and NW-SE. They add a component of 'thick-skinned' transpression to the generally 'thin-skinned' compressional regime in the basin. These deep-rooted fault lines represent zones of weakness, above which salt-related pop-up structures and thrust

  8. Hotspots within the Transboundary Selenga River Basin

    NASA Astrophysics Data System (ADS)

    Kasimov, Nikolay; Lychagin, Mikhail; Chalov, Sergey

    2013-04-01

    Gathering the efficient information on water pollution of transboundary river systems remains the crucial task in international water management, environmental pollution control and prevention health problems. Countries, located in the low parts of the river basins, depend on the water strategy and water use in the adjacent countries, located upstream. Surface water pollution is considered to be the most serious problem, facing the above-mentioned countries. Large efforts in terms of field measurement campaigns and (numerical) transport modeling are then typically needed for relevant pollution prediction and prevention. Russian rivers take inflow from 8 neighboring countries. Among them there are 2 developing economies - People Republic of China and Mongolia, which are located in water-scarce areas and thus solve their water-related problems through the consumption of international water. Negative change of water runoff and water quality in the foreign part of transboundary river is appeared inside Russian territory with more or less delay. The transboundary river system of Selenga is particularly challenging, being the biggest tributary of Lake Baikal which is the largest freshwater reservoir in the world. Selenga River contributes about 50 % of the total inflow into Baikal. It originates in the mountainous part of Mongolia and then drains into Russia. There are numerous industries and agricultural activities within the Selenga drainage basin that affect the water quality of the river system. Absence of the single monitoring system and predictive tools for pollutants transport in river system requires large efforts in understanding sources of water pollution and implemented data on the relevant numerical systems for the pollution prediction and prevention. Special investigations in the Selenga river basin (Mongolia and Russia) were done to assess hot spots and understand state-of-the art in sediment load, water chemistry and hydrobiology of transboundary systems

  9. Radionuclides in the Great Lakes basin.

    PubMed

    Ahier, B A; Tracy, B L

    1995-12-01

    The Great Lakes basin is of radiologic interest due to the large population within its boundaries that may be exposed to various sources of ionizing radiation. Specific radionuclides of interest in the basin arising from natural and artificial sources include 3H, 14C, 90Sr, 129I, 131I, 137Cs, 222Rn, 226Ra, 235U, 238U, 239Pu, and 241Am. The greatest contribution to total radiation exposure is the natural background radiation that provides an average dose of about 2.6 mSv/year to all basin residents. Global fallout from atmospheric nuclear weapons tests conducted before 1963 has resulted in the largest input of anthropogenic radioactivity into the lakes. Of increasing importance is the radionuclide input from the various components of the nuclear fuel cycle. Although the dose from these activities is currently very low, it is expected to increase if there is continued growth of the nuclear industry. In spite of strict regulations on design and operation of nuclear power facilities, the potential exists for a serious accident as a result of the large inventories of radionuclides contained in the reactor cores; however, these risks are several orders of magnitude less than the risks from other natural and man-made hazards. An area of major priority over the next few decades will be the management of the substantial amounts of radioactive waste generated by nuclear fuel cycle activities. Based on derived risk coefficients, the theoretical incidence of fatal and weighted nonfatal cancers and hereditary defects in the basin's population, attributable to 50 years of exposure to natural background radiation, is conservatively estimated to be of the order of 3.4 x 10(5) cases. The total number of attributable health effects to the year 2050 from fallout radionuclides in the Great Lakes basin is of the order of 5.0 x 10(3). In contrast, estimates of attributable health effects from 50 years of exposure to current nuclear fuel cycle effluent in the basin are of the order of 2

  10. Mesozoic Cenozoic history of the Congo Basin

    NASA Astrophysics Data System (ADS)

    Giresse, Pierre

    2005-10-01

    Geophysical surveys and drilling of deep wells have recently led to the recognition of underlying Precambrian basement, and to an interpretation of the structural evolution of the Congo Basin. Deformation estimated as Late Cambrian to Early Ordovician corresponds to the late Pan-African event more accurately dated as end-early Cambrian in West Africa. Subsequently, Paleozoic deformation led to widespread erosion and the development of a marked regional unconformity. The 1000-m-thick mostly continental deposition during the Cretaceous and Tertiary did not involve a noticeable subsidence process. There was no volcanism during this deposition, except at the Early Cretaceous, with the advent of kimberlites that are distributed over the border of the Cuvette. As a consequence most of the diamonds were transported northward or southward from upstream sources. The Mesozoic sediments of the Congo Basin were formed in lacustrine or lagoonal basins close to the sea level as demonstrated by some intercalations with marine fossils. In the eastern part of the basin, a limited marine connection during the Kimmeridgian was only possible with a gulf belonging to the young Indian Ocean. In southern Kasai, the same Kimmeridgian transgression is observed. In the northern part of the basin, a probable Cenomanian marine connection was suggested between the Tethys and the South Atlantic, and the marine deposition at Kipala suggests a connection with the Trans-Saharan corridor during the Late Cretaceous. The geometry of the continental Mesozoic and Cenozoic deposits begins with beds overlying a widespread planation level unconformity and/or the presence of gravel or conglomerate in the lower portion. The Sables Ocres Series and the Grès Polymorphes Series rest on the planation levels of Late Cretaceous and mid-Tertiary ages respectively. Mechanical composition and morphoscopic characters argue for a dominant eolian transport for the Grès Polymorphes and for a fluvial deposition for the

  11. Radionuclides in the Great Lakes basin.

    PubMed Central

    Ahier, B A; Tracy, B L

    1995-01-01

    The Great Lakes basin is of radiologic interest due to the large population within its boundaries that may be exposed to various sources of ionizing radiation. Specific radionuclides of interest in the basin arising from natural and artificial sources include 3H, 14C, 90Sr, 129I, 131I, 137Cs, 222Rn, 226Ra, 235U, 238U, 239Pu, and 241Am. The greatest contribution to total radiation exposure is the natural background radiation that provides an average dose of about 2.6 mSv/year to all basin residents. Global fallout from atmospheric nuclear weapons tests conducted before 1963 has resulted in the largest input of anthropogenic radioactivity into the lakes. Of increasing importance is the radionuclide input from the various components of the nuclear fuel cycle. Although the dose from these activities is currently very low, it is expected to increase if there is continued growth of the nuclear industry. In spite of strict regulations on design and operation of nuclear power facilities, the potential exists for a serious accident as a result of the large inventories of radionuclides contained in the reactor cores; however, these risks are several orders of magnitude less than the risks from other natural and man-made hazards. An area of major priority over the next few decades will be the management of the substantial amounts of radioactive waste generated by nuclear fuel cycle activities. Based on derived risk coefficients, the theoretical incidence of fatal and weighted nonfatal cancers and hereditary defects in the basin's population, attributable to 50 years of exposure to natural background radiation, is conservatively estimated to be of the order of 3.4 x 10(5) cases. The total number of attributable health effects to the year 2050 from fallout radionuclides in the Great Lakes basin is of the order of 5.0 x 10(3). In contrast, estimates of attributable health effects from 50 years of exposure to current nuclear fuel cycle effluent in the basin are of the order of 2

  12. Basin analysis and petroleum potential of Michigan Basin: deposition and subsidence history from Middle Ordovician (Trenton Formation) to Early Devonian

    SciTech Connect

    Nurmi, R.D.

    1984-12-01

    The history of the Michigan basin (Early Ordovician to Early Devonian) is that of a nonuniformly subsiding basin, with the Michigan basin, at times, nearly disappearing as either a topographic feature or a depositional center. This history is interpreted from the analysis of lithostratigraphic units, time stratigraphic features, and log formats (term by J. Forgotson). These units are defined for wells throughout the Michigan basin, and they extended eastward into the Appalachian basin. The definition and thickness mapping of these lithostratigraphic units and formats are accomplished using well cuttings, cores, and wire-line geophysical well logs. From these data, it is possible to interpret the major aspects of both the subsidence and depositional history of the basin. During deposition of both the Trenton limestones and Early Silurian carbonates and shales, the Michigan basin behaved as if it were part of the greater Appalachian basin, whereas prior to the deposition of the Trenton (Middle Ordovician) and during Middle and Late Silurian, the Michigan basin was an entity separate from, and with an apparent structural independence of, the greater Appalachian basin. The structural and topography of the Trenton prior to the deposition of the Utica Shale was mapped throughout Michigan to provide insight into the nature of petroleum entrapment in the Trenton formation. The structural entrapment of petroleum in southeast Michigan contrasts with the combination diagenetic to structural Albio-Scipio trend of south-central Michigan. Evidence is available that more of these two types of traps occur in unproducing areas of the Michigan basin.

  13. New exploration targets in Malaysia: Deep sandstone reservoirs in Malay basin and turbidites in Sabah basin

    SciTech Connect

    Ngah, K.B. )

    1996-01-01

    Much of the production in Malaysia is from middle to upper Miocene sandstones and carbonates in three main basins: Malay, Sarawak (Its three subbasins-Central Luconia, Balingian and Baram), and Sabah. Fifteen fields produce an average of 630,000 bopd and 3.0 bcfgpd. More than 4.0 billion barrels of oil and 20 tcf of gas have been produced, and reserves are 4.2 billion barrels of oil and 90 tcf. Oil production will decline within the next 1 0 years unless new discoveries are made and/or improved oil recovery methods introduced, but gas production of 5 tcf, expected after the turn of the century, can be sustained for several decades. Successful exploratory wells continue to be drilled in the Malaysian Tertiary basins, and others are anticipated with application of new ideas and technology. In the Malay basin, Miocene sandstone reservoirs in Groups L and M have been considered as very [open quote]high risk[close quotes] targets, the quality of the reservoirs has generally been thought to be poor, especially toward the basinal center, where they occur at greater depth. The cause of porosity loss is primarily burial-related. Because of this factor and overpressuring, drilling of many exploration wells has been suspended at or near the top of Group L. In a recent prospect drilled near the basinal axis on the basis of advanced seismic technology, Groups L and M sandstones show fair porosity (8-15%) and contain gas. In the Sabah basin, turbidite play has received little attention, partly because of generally poor seismic resolution in a very complex structural setting. Only one field is known to produce oil from middle Miocene turbidities. However, using recently acquired 3-D seismic data over this field, new oil pools have been discovered, and they are currently being developed. These finds have created new interest, as has Shell's recent major gas discovery from a turbidite play in this basin.

  14. New exploration targets in Malaysia: Deep sandstone reservoirs in Malay basin and turbidites in Sabah basin

    SciTech Connect

    Ngah, K.B.

    1996-12-31

    Much of the production in Malaysia is from middle to upper Miocene sandstones and carbonates in three main basins: Malay, Sarawak (Its three subbasins-Central Luconia, Balingian and Baram), and Sabah. Fifteen fields produce an average of 630,000 bopd and 3.0 bcfgpd. More than 4.0 billion barrels of oil and 20 tcf of gas have been produced, and reserves are 4.2 billion barrels of oil and 90 tcf. Oil production will decline within the next 1 0 years unless new discoveries are made and/or improved oil recovery methods introduced, but gas production of 5 tcf, expected after the turn of the century, can be sustained for several decades. Successful exploratory wells continue to be drilled in the Malaysian Tertiary basins, and others are anticipated with application of new ideas and technology. In the Malay basin, Miocene sandstone reservoirs in Groups L and M have been considered as very {open_quote}high risk{close_quotes} targets, the quality of the reservoirs has generally been thought to be poor, especially toward the basinal center, where they occur at greater depth. The cause of porosity loss is primarily burial-related. Because of this factor and overpressuring, drilling of many exploration wells has been suspended at or near the top of Group L. In a recent prospect drilled near the basinal axis on the basis of advanced seismic technology, Groups L and M sandstones show fair porosity (8-15%) and contain gas. In the Sabah basin, turbidite play has received little attention, partly because of generally poor seismic resolution in a very complex structural setting. Only one field is known to produce oil from middle Miocene turbidities. However, using recently acquired 3-D seismic data over this field, new oil pools have been discovered, and they are currently being developed. These finds have created new interest, as has Shell`s recent major gas discovery from a turbidite play in this basin.

  15. I-Xe ages of Campo del Cielo silicates as a record of the complex early history of the IAB parent body

    NASA Astrophysics Data System (ADS)

    Pravdivtseva, O.; Meshik, A.; Hohenberg, C. M.; Kurat, G.

    2013-12-01

    Using in situ laser analyses of a polished thin section from the IAB iron meteorite Campo del Cielo, we identified two silicate grains rich in radiogenic 129*Xe, Cr-diopside, and oligoclase, excavated them from the metal, and irradiated them with thermal neutrons for I-Xe dating. The release profiles of 129*Xe and 128*Xe are consistent with these silicates being diopside and oligoclase, with activation energies, estimated using Arrhenius plots, of ˜201 and ˜171 kcal mole-1, respectively. The 4556.4 ± 0.4 Ma absolute I-Xe age of the more refractory diopside is younger than the 4558.0 ± 0.7 Ma I-Xe age of the less refractory oligoclase. We suggest that separate impact events at different locations and depths on a porous initial chondritic IAB parent body led to the removal of the melt and recrystallization of diopside and oligoclase at the times reflected by their respective I-Xe ages. The diopside and oligoclase grains were later brought into the studied inclusion by a larger scale catastrophic collision that caused breakup and reassembly of the debris, but did not reset the I-Xe ages dating the first events. The metal melt most probably was <1250 °C when it surrounded studied silicate grains. This reassembly could not have occurred earlier than the I-Xe closure in diopside at 4556.4 ± 0.4 Ma.

  16. Analysis of the Astronomical Concepts Presented by Teachers of Science, Physics, and Mathematics of São José dos Campos / SP Municipality

    NASA Astrophysics Data System (ADS)

    Pereira Gonzaga, Edson; Voelzke, Marcos Rincon

    2013-11-01

    The aim of this work is to conduct a survey of alternative conceptions about the basic concepts of Astronomy from schoolteachers in the City of São José dos Campos. This study covers the the state-run education system and complies with legal documents related to the curriculum of educational systems, such as the Curriculum of São Paulo State and the Parameters of the National Curriculum (PCN). Alternative conceptions, mentioned in Langhi (2009) as very important, were used, because it is believed that if a student can learn these concepts before the methodological intervention, it is possible to prepare contextualized presentations for teachers, and consequently students, to compare what they already know with the new information they obtain in the sessions at the digital mobile planetarium (DMP) of the Universidade Cruzeiro do Sul. Afterwards, they may discuss in a forum, in the form of debate, seeking to draw conclusions relevant to the topic, and transmitting the same to students in Basic Education (EB). This is a case study with a quantitative survey and a qualitative analysis of data on astronomical concepts collected through two questionnaires, one before and one after the intervention, respecting the implementation period of the study,- here called methodological intervention of content presentations at the mobile planetarium - and on respective discussions.

  17. Ecological aspects of phlebotomines (Diptera: Psychodidae) in endemic area of visceral leishmaniasis, Campo Grande, State of Mato Grosso do Sul, Brazil.

    PubMed

    Oliveira, Alessandra Gutierrez; Galati, Eunice Aparecida Bianchi; Fernandes, Carlos Eurico; Dorval, Maria Elizabeth Cavalheiros; Brazil, Reginaldo Peçanha

    2012-01-01

    Aspects of phlebotomine behavior were investigated in the city of Campo Grande, Mato Grosso do Sul state. The insects were captured weekly during December 2003 to November 2005, with Centers for Disease Control light traps at seven different sites including forests and residential areas. In total, 11,024 specimens (7,805 males and 3,219 females) were collected, from which 9,963 (90.38%) were identified as Lutzomyia longipalpis, the proven vector of American visceral leishmaniasis agent. The remaining 9.62% comprised 21 species. L. longipalpis was the most frequent species in all sampled sites, and the first in the ranking of standardized species abundance index. In residential areas this species clearly predominated in the peridomicile (90.96%), in contrast to the intradomicile (9.04%); in animal shelters, it was more numerous in hen houses and prevailed at ground level, inside, and at forest edge around the residences; this aspect is worrying because this insect may remain sheltered in forested environments during the use of insecticides in homes. In the forest environment, other probable or proven vector of cutaneous leishmaniasis agents were also captured such as Lutzomyia whitmani (=Nyssomyia whitmani, sensu Galati), Lutzomyia antunesi (=Nyssomyia antunesi, sensu Galati), and Lutzomyia flaviscutellata (=Bichromomyia flaviscutellata, sensu Galati).

  18. Paleogeographic and paleotectonic setting of sedimentary basins in the Sevier thrust belt and hinterland, eastern Great Basin

    SciTech Connect

    Schmitt, J.G. . Dept. of Earth Sciences); Vandervoort, D.S. . Dept. of Geological Sciences); Suydam, J.D. . Dept. of Geology)

    1993-04-01

    The eastern Great Basin contains a sparse record of broadly distributed Cretaceous sedimentary rocks which record: evolution of intermontane basins during development of the Sevier (Sv)contractional orogen and incipient extensional collapse of the elevated Sv hinterland (east-central NV), and complex tectono-sedimentary interactions between frontal thrust belt structures and the western margin of the adjacent foreland basin. Palinspastic restoration of these strata and associated structures to pre-Tertiary extension positions reveals a clearer pictures of Cretaceous basin paleogeography and allows comparison with the Puna/Altiplano plateau and precordillera thrust belt of the Neogene Andean orogen. Two syntectonic stratal assemblages are present in east-central NV. Lower Cretaceous alluvial strata (Newark Canyon Fm) record basin development coeval with emergence of contractional structures in the Sv hinterland. Localized early Cretaceous basins were possibly piggyback immature; periods of open drainage to the to the east and south suggest connection with the nascent Sv foreland basin to the east (Cedar Mountain/Sanpete Fms) prior to major thrust loading in central Utah. Development of hinterland structures is almost recorded by Aptian-Albian foreland basin alluvial deposits in SW Utah (Dakota Fm) and southern Nevada (Willow Tank Fm). Upper Cretaceous to Eocene strata (Sheep Pass Fm) record inception of regionally abundant alluvial-lacustrine basins which developed in response to onset of latest Cretaceous extension and associated collapse of the Sv hinterland. Evolution of the structurally complex western margin of the Sv foreland basin is recorded in Cretaceous through Eocene strata deposited in: piggyback basins which were at times hydrologically connected to the adjacent foreland basins, and thrust-proximal portions of the foreland basin. These proximal areas are characterized by folding and faulting of basin fill and development of intrabasinal unconformities.

  19. Tectonic History and Modelling of South Caspian Basin

    NASA Astrophysics Data System (ADS)

    Korotaev, M.; Nikishin, A.; Ershov, A.; Brunet, M.-F.

    South Caspian Basin is situated to the east from Caucasus mountains, to the north from Alborz mountain and to the west from Turkmenia. Basin is underlyed by oceanic crust and has extremely high thickness of sediments - up to 22 km. Generally, sedi- ments of South Caspian are divided in 9 complexes (by seismic data): from Jurassic to Quaternary, mostly terrigenous sediments. Modern stress fields obtained from struc- tural data, earthquakes data and GPS data shows compressional environments in South Caspian Region. We propose that the South Caspian Basin was opened in Callovian- Late Jurassic. Callovian-Late Jurassic rapid subsidence event is well documented for the Pre-Caucasus area. We can conclude that a large back-arc deep water basin with very thinned to local oceanic crust originated during Callovian-Late Jurassic which in- cluded Great Caucasus Trough, South Caspian Basin and Kopet-Dagh Basin. It could be recognised the following main stages of the basin history: Callovian-Late Jurassic - that main rifting and crustal extension epoch; Cretaceous-Eocene - gentle thermal sub- sidence affected by stress events; Oligocene-Miocene - rapid subsidence with domi- nant clay deposition within the basin; Pliocene-Quaternary - unusual rapid subsidence of the South Caspian Basin coincided with mountain uplift of the Great Caucasus, Kopet-Dagh and Alborz. We made a backstripping reconstruction along the seismic profile in the central part of the south Caspian Basin. We obtained main peak of the tectonic subsidence for the South Caspian Basin in the Pliocene time - 2 km of the tectonic subsidence and tectonic subsidence rate up to 1200 m/Ma. Rapid subsidence of the basin was contemporaneous with increase of compression and orogenesis on the borders of the basin. We examine the hypothesis, explaining this rapid syncompres- sional subsidence by flexural response of the basin lithosphere to increase of imposed compressional force Lithosphere of the investigated South Caspian

  20. Iron control in the Appalachian Basin

    SciTech Connect

    Dill, W.R.; Fredette, G.

    1983-11-01

    The Appalachian Basin presents one of the most challenging production and stimulation problems because of the iron content of its hydrocarbon producing formations. A variety of iron compounds in the producing formations present problems that have to be considered to effectively stimulate these formations. A research program was initiated in the later part of 1980 to determine methods of more effectively controlling the iron problems in the Appalachian Basin. Results of this study provide data for comparing the effectiveness of various iron control systems that are used in acid stimulation or breakdown techniques that minimize the release of acid insoluble solids and stabilizes them to decrease the detrimental effect caused by fines migration. Also developed in this study was an iron control system that helps the compatibility of the treating fluid with ferrous iron in the formation water. Flow test data and field results indicate the effectiveness of these iron control systems and treating techniques.

  1. Hydrologic data for Soldier Creek Basin, Kansas

    USGS Publications Warehouse

    Carswell, William J.

    1978-01-01

    Selected hydrologic data collected in the Soldier Creek basin in northeastern Kansas are available on magnetic tape in card-image format. Data on the tape include water discharge in fifteen-minute and daily time intervals; rainfall in fifteen-minute and daily time intervals; concentrations and particle sizes of suspended sediment; particle sizes of bed material; ground-water levels; and chemical quality of water in concentrations of selected constituents. The data-collection system includes: (1) 7 recording streamflow stations; (2) 5 recording rainfall stations; (3) 51 nonrecording rainfall stations located within and adjacent to the basin; (4) 31 ground-water observation wells (two recording); and (5) intermittent chemical quality of water and sediment sampling sites. Examples of the information on magnetic tape for each type of data collected are presented in computer-printout format. (Woodard-USGS)

  2. Formation of the Orientale lunar multiring basin

    NASA Astrophysics Data System (ADS)

    Johnson, Brandon C.; Blair, David M.; Collins, Gareth S.; Melosh, H. Jay; Freed, Andrew M.; Taylor, G. Jeffrey; Head, James W.; Wieczorek, Mark A.; Andrews-Hanna, Jeffrey C.; Nimmo, Francis; Keane, James T.; Miljković, Katarina; Soderblom, Jason M.; Zuber, Maria T.

    2016-10-01

    Multiring basins, large impact craters characterized by multiple concentric topographic rings, dominate the stratigraphy, tectonics, and crustal structure of the Moon. Using a hydrocode, we simulated the formation of the Orientale multiring basin, producing a subsurface structure consistent with high-resolution gravity data from the Gravity Recovery and Interior Laboratory (GRAIL) spacecraft. The simulated impact produced a transient crater, ~390 kilometers in diameter, that was not maintained because of subsequent gravitational collapse. Our simulations indicate that the flow of warm weak material at depth was crucial to the formation of the basin’s outer rings, which are large normal faults that formed at different times during the collapse stage. The key parameters controlling ring location and spacing are impactor diameter and lunar thermal gradients.

  3. Hydrocarbon prospects of southern Indus basin, Pakistan

    SciTech Connect

    Quadri, V.U.N.; Shuaib, S.M.

    1986-06-01

    The Southern Indus basin extends approximately between lat. 23/sup 0/ and 28/sup 0/31'N, and from long. 66/sup 0/E to the eastern boundary of Pakistan. Of the 55 exploratory wells drilled (1955-1984), 27 were based on results of multifold seismic surveys. Five commercial oil discoveries and one gas discovery in Cretaceous sands, three gas discoveries in Paleocene limestone or sandstone, and one gas-condensate discovery from lower Eocene limestone prove that hydrocarbons are present. The main hydrocarbon fairways are Mesozoic tilted fault blocks. Tertiary reefal banks, and drape and compressional anticlines. Older reservoirs are accessible toward the east and northeast, and younger mature source rocks are to the west, including offshore, of the Badin block oil field area. The Indus offshore basin reflects sedimentation associated with Mesozoic rifting of the Pakistan-Indian margin, superimposed by a terrigenous clastic depositional system comprised of deltas, shelves, and deep-sea fans of the Indus River.

  4. Susquehanna River Basin Hydrologic Observing System (SRBHOS)

    NASA Astrophysics Data System (ADS)

    Reed, P. M.; Duffy, C. J.; Dressler, K. A.

    2004-12-01

    In response to the NSF-CUAHSI initiative for a national network of Hydrologic Observatories, we propose to initiate the Susquehanna River Basin Hydrologic Observing System (SRBHOS), as the northeast node. The Susquehanna has a drainage area of 71, 410 km2. From the headwaters near Cooperstown, NY, the river is formed within the glaciated Appalachian Plateau physiographic province, crossing the Valley and Ridge, then the Piedmont, before finishing its' 444 mile journey in the Coastal Plain of the Chesapeake Bay. The Susquehanna is the major source of water and nutrients to the Chesapeake. It has a rich history in resource development (logging, mining, coal, agriculture, urban and heavy industry), with an unusual resilience to environmental degradation, which continues today. The shallow Susquehanna is one of the most flood-ravaged rivers in the US with a decadal regularity of major damage from hurricane floods and rain-on-snow events. As a result of this history, it has an enormous infrastructure for climate, surface water and groundwater monitoring already in place, including the nations only regional groundwater monitoring system for drought detection. Thirty-six research institutions have formed the SRBHOS partnership to collaborate on a basin-wide network design for a new scientific observing system. Researchers at the partner universities have conducted major NSF research projects within the basin, setting the stage and showing the need for a new terrestrial hydrologic observing system. The ultimate goal of SRBHOS is to close water, energy and solute budgets from the boundary layer to the water table, extending across plot, hillslope, watershed, and river basin scales. SRBHOS is organized around an existing network of testbeds (legacy watershed sites) run by the partner universities, and research institutions. The design of the observing system, when complete, will address fundamental science questions within major physiographic regions of the basin. A nested

  5. Cold Pools in the Columbia Basin

    SciTech Connect

    Whiteman, Charles D.; Zhong, Shiyuan; Shaw, William J.; Hubbe, John M.; Bian, Xindi; Mittelstadt, J.

    2001-01-01

    Persistent midwinter cold air pools produce multi-day periods of cold, dreary weather in valleys and basins. Persistent stable stratification leads to the buildup of pollutants and moisture in the pool. Because the pool sometimes has temperatures below freezing while the air above is warmer, freezing precipitation often occurs with consequent effects on transportation and safety. Forecasting the buildup and breakdown of these cold pools is difficult because the physical mechanisms leading to their formation, maintenance, and destruction have received little study. This paper provides a succinct meteorological definition of a cold pool, develops a climatology of Columbia Basin cold pools, and analyzes remote and in situ temperature and wind sounding data for two winter cold pool episodes that were accompanied by fog and stratus, illustrating many of the physical mechanisms affecting cold pool evolution.

  6. Insights into Mejerda basin hydrogeology, Tunisia

    NASA Astrophysics Data System (ADS)

    Guellala, Rihab; Tagorti, Mohamed Ali; Inoubli, Mohamed Hédi; Amri, Faouzi

    2012-09-01

    The present study concentrates on the interpretation of Vertical Electrical Soundings (VES) and well logs to understand the geometry and the functioning of the Ghardimaou multilayered aquifer, a potential target for water supply in the Mejerda basin (Tunisia). The analysis of isobath and isopach maps established in this study, shows a tectonic influence on the reservoirs structure; the Villafranchian folding and the NE-SW, and E-W normal faulting in the recent Quaternary created an aquifer system compartmentalized by raised and tilted blocks. Geoelectrical cross sections reveal that this structure influences the thickness of permeable formations and the groundwater circulation. These results will be useful for rationalizing the future hydrogeological research that will be undertaken in the Mejerda basin.

  7. Utility of San Juan basin silcretes

    SciTech Connect

    Gassaway, J.S. )

    1989-09-01

    Silcretes are silicified paleosols that formed as part of deep-weathering profiles during depositional hiatuses under humid climatic regimes. They provide chronostratigraphic support for hypotheses regarding local and regional tectonic and surface events. Silcrete occurs in the San Juan basin (SJB), near the top of the Kirtland Shale (Cretaceous), in the Ojo Alamo Sandstone (Paleocene), and in the Nacimiento Formation (Paleocene). These occurrences mark the southern limit of a 1,000 mi-long, discontinuous outcrop of silcrete discovered during reconnaissance of 16 Western Interior basins. These silcretes, common in Upper Cretaceous to middle Paleocene rocks, are rare in older and younger rocks. Recognition of silcrete occurrences may prove useful to field geologists where other chronostratigraphic information is absent. For example, geologists searching for the K-T boundary could use the lowest silcrete as a starting point.

  8. Proposed Great Salt Lake Basin Hydrologic Observatory

    NASA Astrophysics Data System (ADS)

    Johnson, W. P.; Tarboton, D. G.

    2004-12-01

    The dynamic physiography and population growth within the Great Salt Lake Basin provide the opportunity to observe climate and human-induced land-surface changes affecting water availability, water quality, and water use, thereby making the Great Salt Lake Basin a microcosm of contemporary water resource issues and an excellent site to pursue interdisciplinary and integrated hydrologic science. Important societal concerns center on: How do climate variability and human-induced landscape changes affect hydrologic processes, water quality and availability, and aquatic ecosystems over a range of scales? What are the resource, social, and economic consequences of these changes? The steep topography and large climatic gradients of the Great Salt Lake Basin yield hydrologic systems that are dominated by non-linear interactions between snow deposition and snow melt in the mountains, stream flow and groundwater recharge in the mid-elevations, and evaporative losses from the desert floor at lower elevations. Because the Great Salt Lake Basin terminates in a closed basin lake, it is uniquely suited to closing the water, solute, and sediment balances in a way that is rarely possible in a watershed of a size sufficient for coupling to investigations of atmospheric processes. Proposed infrastructure will include representative densely instrumented focus areas that will be nested within a basin-wide network, thereby quantifying fluxes, residence times, pathways, and storage volumes over a range of scales and land uses. The significant and rapid ongoing urbanization presents the opportunity for observations that quantify the interactions among hydrologic processes, human induced changes and social and economic dynamics. One proposed focus area will be a unique, highly instrumented mountain-to-basin transect that will quantify hydrologic processes extending from the mountain ridge top to the Great Salt Lake. The transect will range in elevation from about 1200 m to 3200 m, with a

  9. Concealed evaporite basin drilled in Arizona

    SciTech Connect

    Rauzi, S.L.

    1996-10-21

    The White Mountains of Arizona are a high forested plateau underlain by volcanic rocks of Late Pliocene and Quaternary age on the south margin of the Colorado plateau province. Elevations range from 6,000--11,590 ft, with winter snow and summer rain but ideal conditions for much of the year. There was no evidence of a Permian evaporite basin concealed beneath the White Mountain volcanic field until 1993, when the Tonto 1 Alpine-Federal, a geothermal test well, was drilled. This test did not encounter thermal waters, but it did encounter a surprisingly thick and unexpected sequence of anhydrite, dolomite, and petroliferous limestone assigned to the Supai (Yeso) formation of Permian age. The Tonto test was continuously cored through the Permian section, providing invaluable information that is now stored at the Arizona Geological Survey in Tucson. The paper describes the area geology and the concealed basin.

  10. Transtensional Basin Forming Processes in the Quaternary of Northern Greece: The Mygdonia Pull-Apart Basin

    NASA Astrophysics Data System (ADS)

    Venetikidis, A.; Schoenbohm, L. M.

    2014-12-01

    The geodynamic setting of the northern Aegean is governed by the superimposition of NE-SW strike-slip deformation, associated with the propagation of the North Anatolian fault zone towards the west, and N-S extension, caused by the suction of the Aegean realm towards the south due to deep seated processes of trench retreat and slab rollback. The Mygdonia basin sits at the westernmost termination of the Kavala-Xanthi-Komotini fault zone, a structure that is considered the northernmost splay of the North Anatolian fault system in the northern Aegean. It is one of the most seismically active regions in continental northern Greece, and it is herein interpreted, for the first time, as a transtensional pull-apart structure that has been progressively established since the Early Pleistocene by westward directed rupture of NW-SE and NE-SW trending oblique slip normal faults and E-W trending normal faults. The interaction of the two, separate, stress regimes in the basin demands decreasing accumulated displacement from west to east to accommodate clockwise rotation. The close correspondence between analogue models of transtensional basins and the observed spatial distribution of faulting in the Mygdonia basin attests to the importance of oblique deformation in the basin-forming processes. Detailed topographic profiles across the fault-bounded ranges confirm the decreasing trend of accrued displacement from east to west. Furthermore, topographic swaths reveal the scaling of faulting into discrete segments along the basin-bounding ranges, while calcrete maturity on abandoned hanging wall fans reveals a towards-the-west diachronous faulting with associated fan sedimentation. The Early Pleistocene age of the initial fill of the basin complex and fault displacements on the order of many hundreds of meters point to dramatic and rapid landscape forming processes in this tectonically active region. The increasing appreciation of the interaction of both strike-slip deformation and

  11. Stratigraphy of the Caloris Basin, Mercury: Implications for Volcanic History and Basin Impact Melt

    NASA Technical Reports Server (NTRS)

    Ernst, Carolyn M.; Denevi, Brett W.; Barnouin, Olivier S.; Klimczak, Christian; Chabot, Nancy L.; Head, James W.; Murchie, Scott L.; Neumann, Gregory A.; Prockter, Louis M.; Robinson, Mark S.; Solomon, Sean C.; Watters, Thomas R.

    2015-01-01

    Caloris basin, Mercury's youngest large impact basin, is filled by volcanic plains that are spectrally distinct from surrounding material. Post-plains impact craters of a variety of sizes populate the basin interior, and the spectra of the material they have excavated enable the thickness of the volcanic fill to be estimated and reveal the nature of the subsurface. The thickness of the interior volcanic plains is consistently at least 2.5 km, reaching 3.5 km in places, with thinner fill toward the edge of the basin. No systematic variations in fill thickness are observed with long-wavelength topography or azimuth. The lack of correlation between plains thickness and variations in elevation at large horizontal scales within the basin indicates that plains emplacement must have predated most, if not all, of the changes in long-wavelength topography that affected the basin. There are no embayed or unambiguously buried (ghost) craters with diameters greater than 10 km in the Caloris interior plains. The absence of such ghost craters indicates that one or more of the following scenarios must hold: the plains are sufficiently thick to have buried all evidence of craters that formed between the Caloris impact event and the emplacement of the plains; the plains were emplaced soon after basin formation; or the complex tectonic deformation of the basin interior has disguised wrinkle-ridge rings localized by buried craters. That low-reflectance material (LRM) was exposed by every impact that penetrated through the surface volcanic plains provides a means to explore near-surface stratigraphy. If all occurrences of LRM are derived from a single layer, the subsurface LRM deposit is at least 7.5-8.5 km thick and its top likely once made up the Caloris basin floor. The Caloris-forming impact would have generated a layer of impact melt 3-15 km thick; such a layer could account for the entire thickness of LRM. This material would have been derived from a combination of lower crust

  12. Crustal structure and basin architecture, De Soto Canyon Salt basin, northeastern Gulf of Mexico

    SciTech Connect

    MacRae, G. . Dept. of Oceanography); Watkins, J.S. . Dept. of Geophysics)

    1992-01-01

    Evolution of sedimentary basins in the Gulf of Mexico can be explained by extensional processes associated with a rifted, passively subsiding continental margin. The De Soto Canyon Salt Basin in the northeastern Gulf of Mexico contains a thick sequence of Mesozoic and Cenozoic sediments which have accumulated almost continuously since the Middle Jurassic, in a relatively stable, slowly subsiding tectonic environment. Simplified isostatic principles based on a lithosphere buoyancy model are used to quantify total tectonic subsidence, crust thickness, crustal extension and crust type. Regional gravity anomaly trends reflect the interpreted crustal configuration. Multifold seismic reflection data and well data are integrated with computed isostatic relations to establish the basic architecture of the basin. An average estimated crustal thickness of 25 km and Beta-values between 1.4 and 1.8 suggest the sedimentary succession is underlain by moderately stretched and attenuated continental crust. Linear east-west and NNW-SSE trends in Beta-value contours indicate major crustal discontinuities in the region of the Mississippi-Alabama-Florida (MAFLA) shelf and beneath the west Florida shelf, respectively. The geometry of dipping sub-salt reflectors defines a major graben extending east-west in the central part of the basin. These structural trends are thought to be in response to Late Triassic-Early Jurassic rifting. The present-day configuration of the basin was established by the Middle Jurassic.

  13. The deep structure of lunar basins - Implications for basin formation and modification

    NASA Technical Reports Server (NTRS)

    Bratt, S. R.; Solomon, S. C.; Head, J. W.; Thurber, C. H.

    1985-01-01

    Models for the crustal structure in the vicinity of nine impact basins, from an inversion of gravity and topographic data from the lunar nearside are presented. The models display a low-density nonmare crustal layer and a mare basalt layer, both of variable thicknesses. Assuming that topography in mare areas is isostatically compensated before the emplacement of mare basalts and that compensation of mare basalt units may be neglected, a decomposition of the gravity anomaly into contributions from Moho relief and mare fill is permitted. Minimum values for mare basalt thicknesses are obtained but because mare basalts and mantle material are similar in density, the thicknesses of the nonmare crust are estimated. An important constraint is the crustal thickness inferred from the Apollo 12 and 14 landing sites from seismic observations. The crustal thickness model indicates that the crust is thinner beneath each of the major nearside basins than in surrounding areas. New bounds on the volume of material ejected from each basin are derived. The geological implications of structural differences among basins for the processes of basin formation and modification are evaluated as functions of time on the moon.

  14. Miocene temblor formation and related basin evolution, southwestern San Joaquin Basin, California

    SciTech Connect

    Gillespie, B.W.

    1988-01-01

    The southwestern San Joaquin basin is an area of great importance for the energy industry and academic basin analysts. Understanding basin evolution is a key concern for explorationists in this essentially pristine province. Temblor Formatio is exposed in an east-west-trending belt that comprises the north flank of the San Emigdio Mountains. Field and subsurface evidence were used to elucidate the geology, depositional environments, and age of the Temblor Formation. The formation represents sand-rich borderland sedimentation in a predominantly deep-marine setting. Deposition of Temblor clastics reflects deformation due to the impingement of the Farallon Pacific ridge with the California-North American plate margin during the middle Oliocene. As a result, severe uplift along the margins of the southern San Joaquin basin, reinforced by a lowstand of global seal level, caused large volumes of coarse, immature clastics to be shed into the rapidly subsiding deep-marine depocenter. Deposition of the Temblor was thus concurrent with the transformation from a convergent margin tectonic regime to one of dextral strike-slip. This transformation was marked by an episode of transform-extension indicated by volcanism, rapid subsidence, and marine transgression during the early Miocene. The Maricopa trough or oceanic connection from the San Joaquin basin to the Pacific Ocean is inferred to have existed between Recruit Pass and Maricopa. The age of the Temblor Formation is late Oligocene to early Miocene. Petroleum production is limited to the upper member in small oil fields flanking the northern Sam Emigdio Mountains.

  15. Integrated Basin Scale Hydropower and Environmental Opportunity Assessment in the Deschutes River Basin, Oregon

    NASA Astrophysics Data System (ADS)

    Voisin, N.; Geerlofs, S. H.; Vail, L. W.; Ham, K. D.; Tagestad, J. D.; Hanrahan, T. P.; Seiple, T. E.; Coleman, A. M.; Stewart, K.

    2012-04-01

    The Deschutes River Basin in Oregon, USA, is home to a number of diverse groups of stakeholders that rely upon the complex snowmelt and groundwater-dominated river system to support their needs, livelihoods, and interests. Basin system operations that vary across various temporal and spatial scales often must balance an array of competing demands including maintaining adequate municipal water supply, recreation, hydropower generation, regulations related to environmental flows, mitigation programs for salmon returns, and in-stream and storage rights for irrigation water supplied by surface water diversions and groundwater pumping. The U.S. Department of Energy's Integrated Basin-scale Opportunity Assessment initiative is taking a system-wide approach to identifying opportunities and actions to increase hydropower and enhance environmental conditions while sustaining reliable supply for other uses. Opportunity scenarios are analyzed in collaboration with stakeholders, through nested integrated modeling and visualization software to assess tradeoffs and system-scale effects. Opportunity assessments are not intended to produce decisional documents or substitute for basin planning processes; assessments are instead intended to provide tools, information, and a forum for catalyzing conversation about scenarios where both environmental and hydropower gains can be realized within a given basin. We present the results of the nested integrated modeling approach and the modeling scenarios in order to identify and explore opportunities for the system.

  16. Hydrothermal circulation in an anisotropic sedimentary basin: Application to the Okinawa back arc basin

    SciTech Connect

    Genthon, P.; Rabinowicz, M. ); Foucher, J.P.; Sibuet, J.C. )

    1990-11-10

    The authors explore the pattern of two-dimensional convection in an highly anisotropical porous medium. This physical situation is relevant to passive margin sedimentary basins consisting of interbedded coarse-grained pervious and shale matrix. They show that permeability anisotropies of the order of 10{sup 2}-10{sup 4} allow for long convective cells, of aspect ratio greater than 10, but that a combination of this parameter with a slight slope of the order of a few percent of the sedimentary layers is required to stabilize these long cells. As an example, they present the Okinawa basin, an active submarine back arc basin, with a sedimentary thickness of about 2 km and a heat flow profile across this basin, varying from 32 to 232 mWm{sup {minus}2} over a distance of 30 km. It is shown that this heat flow variation is difficult to explain with conductive mechanisms only but is well reproduced by different convective models relying on permeability anisotropy plus slope. Although the insufficient thermal and structural constraints did not allow them to build a unique model, the whole set of possible fits to the heat flow data may restrict the mean hydraulic parameters of the basin. A vertical permeability of a few tens of milidarcy and an anisotropy greater than 100 are required to produce the expected stable and active large-scale circulation. It is suggested in conclusion that this type of circulation might be active in oil- or oil-forming element migration.

  17. Serenitatis multi-ringed basin - Regional geology and basin ring interpretation

    NASA Technical Reports Server (NTRS)

    Head, J. W., III

    1979-01-01

    New topographic data allow a reassessment of the ring structure and distribution of facies of the Serenitatis basin (SB) and correlation with the younger and essentially same-size Orientale basin. Three major rings of the main (southern) SB are mapped: the Linne ring, outlined by mare ridges, average diameter 420 km; the Haemus ring, outlined by basin-facing scarps and massifs with crenulated borders, 610 km; and the Vitruvius ring, outlined by basin-facing linear scarps and massifs, 880 km. The second ring is interpreted as the rim of the transient cavity, while Serenitatis ejecta should be present in significant amounts at the junction of the Serenitatis and Imbrium third rings. The new reconstruction indicates that portions of the SB are better preserved than previously thought, consistent with recent stratigraphic and sample studies that suggest an age (as young as 3.87 plus or minus 0.04 b.y.) for SB which is older than, but close to, the time of formation of the Imbrium basin.

  18. Basin-wide architecture of sandstone reservoirs in the Fort Union Formation, Wind River basin, Wyoming

    SciTech Connect

    Flores, R.M.; Keighin, C.W.; Keefer, W.R. )

    1991-06-01

    Architecture of hydrocarbon-bearing sandstone reservoirs of the Paleocene Fort Union Formation in the Wind River basin, Wyoming, was studied using lithofacies, grain size, bounding surfaces, sedimentary structures, internal organization, and geometry. Two principal groups of reservoirs, both erosionally based and fining upward, consist of either conglomeratic sandstone or sandstone lithofacies. Two types of architecture were recognized in conglomeratic sandstone reservoirs: (1) heterogeneous, multistacked, lenticular and (2) homogeneous, multiscoured, wedge-sheet bodies. Three types of architecture were recognized in sandstone reservoirs: (3) heterogeneous, multistacked, elongate; (4) homogeneous, multilateral, lenticular; and (5) homogeneous, ribbon-lensoid bodies. Conglomeratic sandstone reservoirs in the southern and southwestern parts of the basin suggest deposition in gravel-bedload fluvial systems influenced by provenance uplift of the Granite and southern Wind River mountains. Type 2 reservoirs represent deposits of eastward-flowing braided streams aggrading an alluvial valley in response to base level rise. Thus, to determine basin-wide architecture of reservoirs requires understanding the interplay between base level conditions, basin subsidence, and provenance uplift. These interrelated factors, in turn, control differences in hierarchies of fluvial systems throughout the basin.

  19. Water resources of Rockland Basin, southeastern Idaho

    USGS Publications Warehouse

    Williams, Rhea P.; Young, H.W.

    1982-01-01

    Rockland basin comprises about 320 sq mi of the Snake River drainage in southeastern Idaho. Mountain ranges bordering the basin are composed predominantly of limestone and are complexly faulted. Major aquifers include Holocene alluvium, Quaternary-Tertiary volcanic rocks, and Tertiary sedimentary rocks. Groundwater occurs under water table conditions except where it is locally confined. Groundwater discharges to springs in the Deep Creek Mountains and maintains perennial streamflow. Near the mouth of Rock Creek, groundwater movement is northward toward the Snake River. Underflow is estimated to be 51,000 acre-ft/yr. Total water yield available to Rockland basin is estimated to be 5.0 in. (85,000 acre-ft) of the estimated 17.3 in. of annual precipitation. Evapotranspiration ranges from 9.9 to 17 in./yr, depending, in part, on altitude of the land surface. An estimated 12,000 acre-ft of surface water and 3,500 acre-ft of groundwater are used annually for irrigation. Less than 100 acre-ft of water is used for public supply, domestic, and stock supplies. East Fork Rock Creek supplies the most surface water for irrigation of agricultural lands. At the present (1980) state of groundwater development in Rockland basin, streams and aquifers are hydraulically connected. Pumping of groundwater in increased quantities from wells near streams will affect groundwater movement and may diminish streamflow. There are no long-term regional water table declines at present. Continued water level monitoring of selected wells may aid in documenting effects of future management practices on the groundwater system. (Author 's abstract)

  20. K Basin sludge treatment process description

    SciTech Connect

    Westra, A.G.

    1998-08-28

    The K East (KE) and K West (KW) fuel storage basins at the 100 K Area of the Hanford Site contain sludge on the floor, in pits, and inside fuel storage canisters. The major sources of the sludge are corrosion of the fuel elements and steel structures in the basin, sand intrusion from outside the buildings, and degradation of the structural concrete that forms the basins. The decision has been made to dispose of this sludge separate from the fuel elements stored in the basins. The sludge will be treated so that it meets Tank Waste Remediation System (TWRS) acceptance criteria and can be sent to one of the double-shell waste tanks. The US Department of Energy, Richland Operations Office accepted a recommendation by Fluor Daniel Hanford, Inc., to chemically treat the sludge. Sludge treatment will be done by dissolving the fuel constituents in nitric acid, separating the insoluble material, adding neutron absorbers for criticality safety, and reacting the solution with caustic to co-precipitate the uranium and plutonium. A truck will transport the resulting slurry to an underground storage tank (most likely tank 241-AW-105). The undissolved solids will be treated to reduce the transuranic (TRU) and content, stabilized in grout, and transferred to the Environmental Restoration Disposal Facility (ERDF) for disposal. This document describes a process for dissolving the sludge to produce waste streams that meet the TWRS acceptance criteria for disposal to an underground waste tank and the ERDF acceptance criteria for disposal of solid waste. The process described is based on a series of engineering studies and laboratory tests outlined in the testing strategy document (Flament 1998).

  1. Sediment thickness in the southern Canada Basin

    USGS Publications Warehouse

    May, S.D.; Grantz, A.

    1990-01-01

    Multichannel seismic reflection data are used, in conjunction with deep crustal seismic refraction data, to estimate the thickness of sediments in the southern Canada Basin of the Arctic Ocean north of Alaska. The sediments are interpreted to be of Hauterivian (mid-Early Cretaceous) to Holocene age. Comparison of the seismic reflection character of seismic reflections in the study area with that in other basins indicates that a base-of-sediment-top of oceanic layer 2 reflection is not present above the depth at which the water-bottom multiple obscures all deeper arrivals, which is in conflict with the conclusions drawn from aeromagnetic, refraction, and other reflection studies. Seismic velocity structure, determined from the reflection data, indicates that the reflections above the multiple are from sedimentary strata. In the absence of seismic reflection evidence for the top of layer 2 above the multiple, we estimate total sediment thickness by using the layer 3 refractions and subtracting an average assumed layer 2 thickness from the top of layer 3. Assuming that an average thickness of oceanic layer 2 (1.4 km) overlies layer 3 in the southern Canada Basin, sediment thickness in the study area is estimated to range between 6.5 km where water depth is 3.8 km to greater than 11 km where the water depth is 2 km. This is nearly double that of any previous estimates and should have a significant effect on calculations such as the age of Canada Basin, regional heat flow, and long-term sedimentation rates. ?? 1990.

  2. Caribbean basin framework, 2: Northern Central America

    SciTech Connect

    Tyburski, S.A.; Gordon, M.B.; Mann, P. )

    1991-03-01

    There are four Jurassic to Recent basin-forming periods in northern Central America (honduras, Honduran Borderlands, Belize, Guatemala, northern Nicaragua): (1) Middle Jurassic-Early Cretaceous rifting and subsidence along normal faults in Honduras and Guatemala; rifts are suggested but are not well defined in Honduras by the distribution of clastic sediments and associated volcanic rocks. Rifting is attributed to the separation of Central America from the southern margin of the North American plate; (2) Cretaceous subsidence recorded by the development of a Cretaceous carbonate platform in Honduras, Guatemala, and Belize; subsidence is attributed to thermal subsidence of the rifted margins of the various blocks; (3) Late Cretaceous-Recent development of a volcanic arc along the western margin of Middle America and the northern margin of Honduras; (4) Late Cretaceous large-scale folding in Honduras, ophiolite obduction, and formation of a foredeep basin in Guatemala (Sepur trough); deformation is attributed to the collision between a north-facing arc in northern Honduras and the Nicaraguan Rise and the passive margin of Guatemala and Belize; and (5) Eocene to Recent strike-slip faulting along the present-day North American-Caribbean plate boundary in Guatemala, northern Honduras, and Belize. Strike-slip faults and basins form a California-type borderlands characterized by elongate basins that appear as half-grabens in profile. Counterclockwise rotation of the central honduras plateau, a thicker and topographically higher-than-average block within the plate boundary zone, is accommodated by rifting or strike-slip faults at its edges.

  3. Prospective Frontier basins off eastern Australia

    SciTech Connect

    Falvey, D.A.; Hinz, K.; Willcox, J.B.; Exon, N.F.; Symonds, P.A.; Williamson, P.E.

    1986-07-01

    Eleven thousand kilometers of high-quality multichannel seismic reflection data have been gathered in four poorly known, but prospective areas off eastern Australia. The Otway basin has an area of 100,000 km/sup 2/, more than half of which is in depths exceeding 500 m. Its Cretaceous and Cenozoic sedimentary sequence is up to 10,000 m thick and is cut by large coast-parallel normal faults. The oldest marine strata are Cenomanian. The basinal area off west Tasmania covers 40,000 km/sup 2/, two-thirds of it in offshelf depths. It contains up to 6000 m of Cretaceous and Cenozoic sequences similar to those of the Otway basin. The Lord Howe Rise is a ribbon of continent off eastern Australia, about 2000 km long and 400 km wide. Much of its crest lies in water depths of 750-1200 m. Up to 4500 m of Mesozoic and Cenozoic sequences has been identified, and extensive faulting, related to the formation of the Tasman Sea, has formed rift basins and horst and graben areas. Simple extension was apparently dominant in the south, and oblique extension in the north. The Queensland Plateau covers 200,000 km/sup 2/, half of which is in water shallower than 1000 m. The plateau behaved as a stable block during and after the Paleogene spreading episode, which formed the Coral Sea to the northeast. About 1000 m of latest Cretaceous and Cenozoic sequences are present above a planated surface on the plateau, and up to 5000 m in the flanking Queensland and Townsville Troughs to the southwest. The sequence beneath the planated surface is believed to contain Cretaceous rift-fill sediments in places.

  4. Sedimentation basin performance at highway construction sites.

    PubMed

    Kalainesan, Sujaya; Neufeld, Ronald D; Quimpo, Rafael; Yodnane, Precha

    2009-02-01

    Sedimentation basins (SBs) are commonly used during highway construction for erosion and sedimentation pollution control as well as for attenuation of overland storm waters. In order to evaluate the sediment removal capacity of these SBs, four basins were selected for monitoring from a new highway construction that extends I-99 to I-80, in Pennsylvania. Between September 2004 and August 2005, ten sampling trips were conducted during which basin inlet and outlet water samples were obtained. The SB samples were analyzed for pH, color, turbidity, total suspended solids (TSS), volatile suspended solids (VSS), total and dissolved iron, magnesium, manganese, aluminum, calcium, sulfate and phosphate. The data showed peaks in concentrations of TSS, total aluminum, total manganese, total iron and total phosphate that closely correlated to localized rainfall peaks. For certain samples, the concentration of TSS in the outlet was higher than the TSS concentration at the basin inlet, suggesting sediment re-suspension. In general SBs managed high flows during wet weather events, but were not effective in capturing particulates. This paper discusses the need for Best Management Practices (BMPs) for the design of SBs that reflect contemporary concerns for management of particle removal and to control the release of particulate-bound metals. This paper also evaluates the water quality impacts of naturally occurring acidic drainages into SBs, as several acidic seeps with pH in the range of 5-6 and having high dissolved concentrations of metals (Fe, Mn, Mg and Ca), sulfate and phosphate were observed draining into the SBs.

  5. K Basin spent nuclear fuel characterization

    SciTech Connect

    LAWRENCE, L.A.

    1999-02-10

    The results of the characterization efforts completed for the N Reactor fuel stored in the Hanford K Basins were Collected and summarized in this single referencable document. This summary provides a ''road map'' for what was done and the results obtained for the fuel characterization program initiated in 1994 and scheduled for completion in 1999 with the fuel oxidation rate measurement under moist inert atmospheres.

  6. Underworld and multi-basin heat flow

    NASA Astrophysics Data System (ADS)

    Quenette, S. M.; O'Neill, C.; Moresi, L. N.; Danis, C. R.; Mansour, J.

    2011-12-01

    We present an over arching method for non-linear heat flow assessments of large, multi-basin systems. Our example is the Sydney-, Gunnedah-, Bowen basins (Danis et al 2011), which covers an area of 800kms by 1900kms and depth of 5kms, on the east coast of Australia. It is used as a baseline towards further fluid and structural geodynamics oriented analysis. In contrast to reservoir scale geothermal models - basin, multi-basin and towards lithosphere scale models exhibit their own challenges in terms of physical/rheological behaviour and computational tractability. For instance we model a non-linear heat flow by means of temperature dependent conductivity, as indicated by Clauser and Huenges (1995), which allows crystalline basement rocks, such as granites, to show for example a significant decrease in conductivity from ambient temperature up to around 400C, dropping from around 3 mK**(units) to around 2. For this modelling, a specialisation of the geodynamics code 'Underworld' (Moresi et al 2007) called Underworld-GT is used. A toolbox is added to the otherwise un-touched Underworld code adding geothermal workflow and context to Underworld. A particular novel feature is the ability to load stratigraphic layers, and/or GoCAD or GeoModeller voxel sets as the constraining geological geometry, whilst allowing the heat assessment models to scale from 1 process to 1000s. Another is the ability to prescribe synthetic drill holes, and its use in stochastic-oriented assessments of model parameters. Following the Underworld platform's approach and its simple PDE abstraction layer, these model configurations from a baseline for further additions to the governing equations such as fluid flow and structure, enabling a bridge between reservoir and continental scale dynamics, albeit with their own computational challenges.

  7. SE Great Basin Play Fairway Analysis

    SciTech Connect

    Adam Brandt

    2015-11-15

    This submission includes a Na/K geothermometer probability greater than 200 deg C map, as well as two play fairway analysis (PFA) models. The probability map acts as a composite risk segment for the PFA models. The PFA models differ in their application of magnetotelluric conductors as composite risk segments. These PFA models map out the geothermal potential in the region of SE Great Basin, Utah.

  8. The stratigraphy of the Trinity Group, East Texas basin

    SciTech Connect

    French, V.L. )

    1991-03-01

    The Lower Cretaceous Trinity Group of the East Texas basin contains formations that have produced oil for a number of years, and while they have been the subject of considerable discussion, little has been said about their character and regional distribution over the entire basin. This regional treatment is critical to an understanding of the tectonic history of the East Texas basin. The Trinity Group consists of facies varying from fluvial sands to marginal marine limestones and shales. In the East Texas basin, Trinity rocks were initially deposited during basinal subsidence and form a wedge of sediments that thicken rapidly eastward. Early Trinity deposition began as clastics were shed from highlands to the north and west and then were deposited within the basin by prograding deltaic systems. Sediment was first deposited as channel-fill and point-bar deposits. Toward the basin, fluvial sands were deposited as destructive deltaic facies. True marine sedimentation was confined to the extreme southeastern part of the basin. Trinity deposition reflects a series of minor transgressive and regressive pulses, with environments ranging from deltaic and shallow open shelf to restricted lagoon. With the buildup of the Stuart City reef system along the southern margin of the basin isolation occurred. During late Trinity, seas covered the entire basin and a large area of the stable Texas platform resulting in deposition of a thick, shallow, open-marine limestone and shale sequence, which marks the end of Trinity deposition.

  9. Dose reduction improvements in storage basins of spent nuclear fuel

    SciTech Connect

    Huang, Fan-Hsiung F.

    1997-08-13

    Spent nuclear fuel in storage basins at the Hanford Site has corroded and contaminated basin water, which has leaked into the soil; the fuel also had deposited a layer of radioactive sludge on basin floors. The SNF is to be removed from the basins to protect the nearby Columbia River. Because the radiation level is high, measures have been taken to reduce the background dose rate to as low as reasonably achievable (ALARA) to prevent radiation doses from becoming the limiting factor for removal of the SW in the basins to long-term dry storage. All activities of the SNF Project require application of ALARA principles for the workers. On the basis of these principles dose reduction improvements have been made by first identifying radiological sources. Principal radiological sources in the basin are basin walls, basin water, recirculation piping and equipment. Dose reduction activities focus on cleaning and coating basin walls to permit raising the water level, hydrolasing piping, and placing lead plates. In addition, the transfer bay floor will be refinished to make decontamination easier and reduce worker exposures in the radiation field. The background dose rates in the basin will be estimated before each task commences and after it is completed; these dose reduction data will provide the basis for cost benefit analysis.

  10. Early, middle, and late Miocene basin development, California

    SciTech Connect

    Bachman, S.B.

    1988-03-01

    Contrary to earlier models of progressive basin development related to northward migration of the Mendocino triple junction, it can now be documented that the major basins of coastal California developed at about the same time in the late Oligocene to early Miocene. This basin development is marked by rapid deepening of basin floors, subsequent changes in depositional facies from nonmarine and shallow marine to deep marine, and widespread volcanism dated at 23-20 Ma. The coastal basins likely formed by rifting and subsidence linked to the proximity of the Farallon-pacific spreading ridge and the subduction of hot young oceanic crust, but cannot be correlated to any existing models of triple junction migration. Indeed, strike-slip restored positions of the coastal basins at their inception indicate that the basins were spread out over about 800 km of the southern coast of California. The Miocene basins were likely larger than the present coastal basins, although their configurations are obscured by late Neogene faulting and erosion. It is likely, however, that paleohighs separated at least some of the margin into proximal and distal basins. With local exceptions, structuring in the Miocene basins was primarily extensional, with widespread strike-slip and thrust tectonics restricted mainly to latest Miocene and younger events. Plate reconstructions suggest several hundred kilometers of transform motion occurred along the California margin during the Miocene, but there is only limited evidence of this movement in the known history of either the basins or the major faults of California. Sedimentation during the Miocene was controlled by both oceanic conditions (biogenic component) and the relative abundance of clastic input. The clastic input was controlled by a combination of proximal vs distal basinal positions, eustatic sea level changes, and local tectonics.

  11. Ensemble predictions of runoff using hydrograph transpositions to ungauged basins

    NASA Astrophysics Data System (ADS)

    de Lavenne, Alban; Cudennec, Christophe

    2014-05-01

    Regionalisation is one common approach for modelling streamflow in ungauged basins. It is sometimes performed on the basis of ensemble modelling and model averaging through the play of parameters of rainfall-runoff models. We propose an original approach for ensemble modelling by transposing physically based time series rather than model's parameters. We applied the approach on 6 sub-basins of the Blavet river in Brittany (France) with area varying from 5 km² to 316 km². Inside this sample of gauged basins, the water provided by hillslopes to the network at a basin scale, called the net rainfall, is assessed by inverting their simple geomorphology based network transfer function. Those net rainfall time series, estimated at an hourly time step on each gauged basin separately, summarise the hydrological behaviour of their hillslopes without the need of any complex modelling. Moreover, it has the advantage of being relatively scale independent which enables its transposition among basins. Once this net rainfall is transposed to an ungauged basin, it is reconvoluted using its own transfer function in order to estimate the hydrograph therein. We propose to combine several gauged basins to perform ensemble modelling prediction. This ensemble modelling provides an indication of uncertainty. Although it is not a robust estimate of the possible flow range, it informs about the variability of basins behaviour inside the studied region and, as a consequence, the relative confidence in those transpositions of hydrograph. By selecting donor basins according to their similarity to the ungauged one, we aim to improve prediction accuracy, reduce uncertainty and check the best way to define hydrological similarity for the choice of the donor basin. It is demonstrated that spatial proximity provides a relatively robust estimate of the best donor basin, and giving more importance to similar basins does not necessarily lead to higher accuracy in simulations compared to a simple net

  12. Hydrocarbon potential of basins along Australia's southern margin

    SciTech Connect

    Willink, R.J. )

    1991-03-01

    Seven discrete sedimentary basins are recognized along the southern margin of the Australian continent; namely, from east to west, the Gippsland, Bass, Sorell, Otway, Duntroon, Bight, and Bremer. All formed since the Late Jurassic in response to the separation of Australia and Antarctica, and to the opening of the Tasman Sea. Only the Gippsland basin, which has proved initial oil reserves exceeding 3.6 billion barrels, is a prolific oil province. The search for oil in the other basins has been virtually fruitless despite many similarities between these basins and the Gippsland in terms of stratigraphy and structural geology. Rift and drift components are discernible in the sedimentary successions of all basins but the precise tectonic controls on respective basin formation remain conjectural. The lack of drilling success in the Bremer, Bight, Duntroon, Otway, and Sorell basins has been attributed mainly to the paucity of mature, oil-prone source rocks. The common occurrence of stranded bitumens along the entire coastline, however, indicates oil generation. The Bass and Gippsland basins are both characterized by excellent oil-prone source rocks developed in Late Cretaceous to Early Tertiary sediments. Limited exploration success in the Bass basin is due to poorer reservoir development. The Gippsland basin is at a mature stage of exploration whereas the other basins are moderately to very sparsely explored. Consequently, there is a comparable potential for undiscovered hydrocarbons in all basins. Success in the under-explored basins will come only to those prepared to challenge the perception of low prospectivity. Many play types remain to be tested by the drill.

  13. Modelling conservation in the Amazon basin.

    PubMed

    Soares-Filho, Britaldo Silveira; Nepstad, Daniel Curtis; Curran, Lisa M; Cerqueira, Gustavo Coutinho; Garcia, Ricardo Alexandrino; Ramos, Claudia Azevedo; Voll, Eliane; McDonald, Alice; Lefebvre, Paul; Schlesinger, Peter

    2006-03-23

    Expansion of the cattle and soy industries in the Amazon basin has increased deforestation rates and will soon push all-weather highways into the region's core. In the face of this growing pressure, a comprehensive conservation strategy for the Amazon basin should protect its watersheds, the full range of species and ecosystem diversity, and the stability of regional climates. Here we report that protected areas in the Amazon basin--the central feature of prevailing conservation approaches--are an important but insufficient component of this strategy, based on policy-sensitive simulations of future deforestation. By 2050, current trends in agricultural expansion will eliminate a total of 40% of Amazon forests, including at least two-thirds of the forest cover of six major watersheds and 12 ecoregions, releasing 32 +/- 8 Pg of carbon to the atmosphere. One-quarter of the 382 mammalian species examined will lose more than 40% of the forest within their Amazon ranges. Although an expanded and enforced network of protected areas could avoid as much as one-third of this projected forest loss, conservation on private lands is also essential. Expanding market pressures for sound land management and prevention of forest clearing on lands unsuitable for agriculture are critical ingredients of a strategy for comprehensive conservation. PMID:16554817

  14. Gas potential of the Rharb Basin, Morocco

    SciTech Connect

    Mohamed, D.; Costagliola, A.

    1995-08-01

    The Rharb basin in northern Morocco is a Tertiary foreland filled by clastic series during Miocene and Pliocene times These sediments, derived from the Prerif to the North-East and the Meseta to the South, are characterized by two main turbiditic sequences during much of the Upper Tortonian/Messinian and Lower Pliocene. These deep water sand deposits were probably related to both uplifting of the Rif and prerif and relative change of sea level. Although the first oil discovery in the basin was made by the beginning of the 1920`s and that over 25 billions cf of gas have been discovered by exploration drilling, the problem still facing exploration in the area is seismic resolution and reprocessing. Recent studies, based on high seismic resolution techniques and general integrated basin study have permitted to gain a deep insight of stratigraphy and distribution of deep water sand within the Upper Miocene series and their fluid content and provide critical data for evaluating hydrocarbon potential. Such evaluation combined with structural configuration and seals allows assessment of different prospects for gas exploration. Out of more 100 amplitude anomalies identified in the area based on new exploration concepts, 7 are recently drilled with 4 discoveries and 8 are proposed for drilling.

  15. Geothermal fluid genesis in the Great Basin

    SciTech Connect

    Flynn, T.; Buchanan, P.K.

    1990-01-01

    Early theories concerning geothermal recharge in the Great Basin implied recharge was by recent precipitation. Physical, chemical, and isotopic differences between thermal and non-thermal fluids and global paleoclimatic indicators suggest that recharge occurred during the late Pleistocene. Polar region isotopic studies demonstrate that a depletion in stable light-isotopes of precipitation existed during the late Pleistocene due to the colder, wetter climate. Isotopic analysis of calcite veins and packrat midden megafossils confirm the depletion event occurred in the Great Basin. Isotopic analysis of non-thermal springs is utilized as a proxy for local recent precipitation. Contoured plots of deuterium concentrations from non-thermal and thermal water show a regional, systematic variation. Subtracting contoured plots of non-thermal water from plots of thermal water reveals that thermal waters on a regional scale are generally isotopically more depleted. Isolated areas where thermal water is more enriched than non-thermal water correspond to locations of pluvial Lakes Lahontan and Bonneville, suggesting isotopically enriched lake water contributed to fluid recharge. These anomalous waters also contain high concentrations of sodium chloride, boron, and other dissolved species suggestive of evaporative enrichment. Carbon-age date and isotopic data from Great Basin thermal waters correlate with the polar paleoclimate studies. Recharge occurred along range bounding faults. 151 refs., 62 figs., 15 tabs.

  16. Frost risks in the Mantaro river basin

    NASA Astrophysics Data System (ADS)

    Trasmonte, G.; Chavez, R.; Segura, B.; Rosales, J. L.

    2008-04-01

    As part of the study on the Mantaro river basin's (central Andes of Perú) current vulnerability to climate change, the temporal and spatial characteristics of frosts were analysed. These characteristics included intensity, frequency, duration, frost-free periods, area distribution and historical trends. Maps of frost risk were determined for the entire river basin, by means of mathematical algorithms and GIS (Geographic Information Systems) tools, using minimum temperature - 1960 to 2002 period, geomorphology, slope, land-use, types of soils, vegetation and life zones, emphasizing the rainy season (September to April), when the impacts of frost on agriculture are most severe. We recognized four categories of frost risks: low, moderate, high and critical. The critical risks (with a very high probability of occurrence) were related to high altitudes on the basin (altitudes higher than 3800 m a.s.l.), while the low (or null) probability of occurring risks were found in the lower zones (less than 2500 m a.s.l.). Because of the very intense agricultural activity and the high sensitivity of the main crops (Maize, potato, artichoke) in the Mantaro valley (altitudes between 3100 and 3300 m a.s.l.), moderate to high frost risks can be expected, with a low to moderate probability of occurrence. Another significant result was a positive trend of 8 days per decade in the number of frost days during the rainy season.

  17. Precipitation recycling in the Amazon basin

    NASA Technical Reports Server (NTRS)

    Eltahir, E. A. B.; Bras, R. L.

    1994-01-01

    Precipitation recycling is the contribution of evaporation within a region to precipitation in that same region. The recycling rate is a diagnostic measure of the potential for interactions between land surface hydrology and regional climate. In this paper we present a model for describing the seasonal and spatial variability of the recycling process. The precipitation recycling ratio, rho, is the basic variable in describing the recycling process. Rho is the fraction of precipitation at a certain location and time which is contributed by evaporation within the region under study. The recycling model is applied in studyiing the hydrologic cycle in the Amazon basin. It is estimated that about 25% of all the rain that falls in the Amazon basin is contributed by evaporation within the basin. This estimate is based on analysis of a data set supplied by the European Centre for Medium-range Weather Forecasts (ECMWF). The same analysis is repeated using a different data set from the Geophysical Fluid Dynamics Laboratory (GFDL). Based on this data set, the recycling ratio is estimated to be 35%. The seasonal variability of the recycling ratio is small compared with the yearly average. The new estimates of the recycling ratio are compared with results of previous studies, and the differences are explained.

  18. Phanerozoic tectonic evolution of Tarim Basin

    SciTech Connect

    Sun Zhaocai; Zhang Yigang

    1995-08-01

    The tectonic evolution of Tarim Basin can be divided into two stages. In the first stage, there developed three Palaeozoic sequences (Pt3-01, O2-3-D and C1-P2), the deposition of which were controlled by Palaeoasian Tectonic Domain. In the second stage, there appeared five Meso-Cenozoic sequences (T1-2, T3, J, K2-E and N1-Q), controlled by Tethys Sea Tectonic Domain. Both of the first sequence of each stage (Pt3-01 and T1-2) are of typical rift-drift facies, overlain by flexural facies. The Palaeozoic tectonic style is characterized by basement-involved, back-thrusted uplifts and the pop-up held inbetween them. The main tectonic style since Late Triassic time has been thin-skin decoupling anticlines developed near the deep troughs in the foreland basins. Corresponding to the two above-mentioned stages, two major petroleum systems were formed. However, the early petroleum system was partly destroyed due to the marked overturn of the basin during Late Palaeozoic time.

  19. Moon - 2 Views of Orientale Basin

    NASA Technical Reports Server (NTRS)

    1990-01-01

    These pictures of the Moon were taken by the Galileo spacecraft at (right photo) 6:47 p.m. PST Dec.8, 1990 from a distance of almost 220,000 miles, and at (left photo) 9:35 a.m. PST Dec. 9, 1990 at a range of more than 350,000 miles. The picture on the right shows the dark Oceanus Procellarum in the upper center, with Mare Imbrium above it and the smaller circular Mare Humorum below. The Orientale Basin, with a small mare in its center, is on the lower left near the limb or edge. Between stretches the cratered highland terrain, with scattered bright young craters on highlands and maria alike. The picture at left shows the globe of the Moon rotated, putting Mare Imbrium on the eastern limb and moving the Orientale Basin almost to the center. The extent of the cratered highlands on the far side is very apparent. At lower left, near the limb, is the South Pole Aitken basin, similar to Orientale but very much older and some 1,200 miles in diameter. This feature was previously known as a large depression in the southern far side; this image shows its Orientale like structure and darkness relative to surrounding highlands.

  20. South Fork Holston River basin 1988 biomonitoring

    SciTech Connect

    Saylor, C.F.; Ahlstedt, S.A.

    1990-06-01

    There is concern over the effects of shifts in land use use practices on the aquatic fauna of streams in the South Fork Holston River basin in northwestern North Carolina and southwestern Virginia. Trout reproduction has noticeably declined in the Watauga River subbasin. The Watauga River and Elk River subbasins have been subjected to commercial and resort development. The Middle fork Holston River and the upper South Fork Holston River subbasins have been affected by agricultural and mining activities, respectively (Cox, 1986). To aid reclamation and management of the South Fork Holston basin, Tennessee Valley Authority (TVA) biologists conducted biomonitoring--including index of biotic integrity and macroinvertebrate sampling--on the Middle Fork Holston, South Fork Holston, Watauga, and Elk Rivers to assess cumulative impairment related to changes in habitat and pollutant loading in these subbasins. Biomonitoring can detect environmental degradation, help document problem areas, and assist in development of strategies for managing water quality. This report discusses the methods and materials and results of the biomonitoring of South Fork Holston River Basin. 13 refs., 5 figs., 12 tabs.

  1. Petroleum exploration in the Amadeus Basin

    NASA Astrophysics Data System (ADS)

    Roe, L. E.

    Although the spectacular outcrops in the Amadeus Basin have attracted researcher for many years, commercial exploration for oil started only in 1958. Up until 1973, 16 petroleum exploration wells were drilled and the major Mereenie Oil and Gas Field and the Palm Valley Gas Field were discovered. In both cases, the principal reservoir is the latest Cambrian-Early Ordovician Pacoota Sandstone; the reservoirs were sourced from the Early Ordovician Horn Valley Siltstone. Due to a combination of adverse circumstances, there was no exploration in the basin between 1973 and 1980. Since activity resumed, 14 further exploratory wells have been drilled and both the Mereenie and Palm Valley Fields have commenced production. The Dingo Gas Field, with flows form the basal part of the latest Proterozoic Arumbera Sandstone, was discovered in 1981. The Dingo Field is currently under study because of low flow rates from the reservoir. Exploration during the 1980's has brought out new concepts regarding the prospectiveness of parts of the basin, many of which have yet to be tested.

  2. Foreland Basin Structures and Remote Sensing

    NASA Technical Reports Server (NTRS)

    Paylor, E. D.

    1985-01-01

    Rocky Mountain foreland basins are somewhat unique in that the basins may exhibit a variety of structural styles. It is generally agreed that shortening has occurred in the foreland basement but the cause is controversial: vertical vs compressional horizontal tectonics. Even when shortening is attributed to compression, the attitude (dip) of the fault plane and whether the horizontal or vertical component of movement is dominant is unconstrained. The controversy is difficult to resolve from surface data alone due to the variety of possible interpretations. Detailed surface mapping and geologic modeling are needed to constrain subsurface interpretations. In many areas of the Wind River and Bighorn basins detailed geologic maps do not exist. State-of-the-art remote sensing data could potentially provide an efficient means of mapping surface geology. State-of-the-art remote sensing systems now provide geometrically correct data at 30 meter pixel size and increased spectral coverage, capable of more detailed geologic analyses. These data can be photographically enlarged to 1:24,000 scale and combined with 7 1/2' uses topographic quads to provide an excellent base map for geologic interpretations.

  3. Structure and dynamics of the Tyrrhenian basin

    SciTech Connect

    Sborshchikov, I.M.; Verjbitsky, E.V.; Schreider, A.A. )

    1988-08-01

    The Tyrrhenian Sea is a recently subsided oceanic basin. Young tholeiitic volcanoes are found in the central part of this sea as well as sea mount fragments of continental blocks formed by Alpine folding complexes. Mesozoic ophiolites are found on Baronie and DeMarchi sea mounts and Site 651 (Leg 107). Soviet investigations show that Baronie serpentinites are covered by thick carbonate rocks of Late Jurassic age, and these deposits are comparable with ophicalcites of the Ligurian Alps. The ophiolites are traced across the basin indicating the connection to north Corsican and Calabrian structures. The fracture zone of 41{degree}N is possibly the fault which controls microplate displacement. Rifting occurred quickly and migrated toward the Eolian arc. There is no direct evidence of regular spreading (linear magnetic anomalies) in the Tyrrhenian Sea now, and opening rate calculations are difficult. Detailed heat-flow data, similar to data of typical spreading centers, allow them to estimate the gradient of the thinning lithosphere outside to axis volcanoes (Vavilov and Marsili). The calculated rifting rate on this basis is about 1-2 cm/year relative to each stretching center. The Tyrrhenian Sea has developed as a back-arc basin within the collision zone of thick continental plates.

  4. Amazonis and Utopia Planitiae: Martian Lacustrine basins

    NASA Technical Reports Server (NTRS)

    Scott, David H.; Rice, James W., Jr.; Dohm, James M.; Chapman, Mary G.

    1992-01-01

    Amazonis and Utopia Planitiae are two large (greater than 10(exp 6) sq. km) basins on Mars having morphological features commonly associated with former lakes. The investigation of these areas is an extension of our previous paleolake studies in the Elysium basin. Using Viking images, we are searching for familiar geologic forms commonly associated with standing bodies of water on Earth. Like Elysium, the two basins exhibit terraces and lineations resembling shorelines, etched and infilled floors with channel-like sinuous markings in places, inflow channels along their borders, and other geomorphic indicators believed to be related to the presence of water and ice. In some areas these features are better displayed than in others where they may be very tenuous; their value as indicators can be justified only by their association with related features. Even though these postulated paleolakes are very young in the Martian stratigraphic sequence, their shoreline features are poorly preserved and they are probably much older than large Pleistocene lakes on Earth.

  5. Miscellaneous chemical basin expedited site characterization report

    SciTech Connect

    Riha, B.D.; Pemberton, B.E.; Rossabi, J.

    1996-12-01

    A total of twenty nine cone penetrometer test (CPT) pushes in three weeks were conducted for vadose zone characterization of the Miscellaneous Chemical Basin (MCB) waste unit at the Savannah River Site. The shallow, unlined basin received liquid chemical wastes over an 18 year period beginning in 1956. This characterization was initiated to determine the vertical and lateral extent of contamination in the vadose zone and to install vadose zone wells for remediation by barometric pumping or active vapor extraction to help prevent further contamination of groundwater. The CPT locations within the waste site were selected based on results from previous shallow soil gas surveys, groundwater contamination data, and the suspected basin center. Geophysical data and soil gas samples were collected at twenty five locations and twenty five vadose zone wells were installed. The wells were screened to target the clay zones and areas of higher soil gas concentrations. The well construction diagrams are provided in Appendix B. Baro-Ball{trademark} valves for enhanced barometric pumping were installed on each well upon completion to immediately begin the remediation treatability study at the site.

  6. 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.

  7. Incentive compatibility and conflict resolution in international river basins: A case study of the Nile Basin

    NASA Astrophysics Data System (ADS)

    Wu, Xun; Whittington, Dale

    2006-02-01

    Nation-states rarely go to war over water, but it is equally rare that water conflicts in an international river basin are resolved through cooperation among the riparian countries that use the shared resources. Gains from cooperation will mean little to individual riparians unless the required cooperative behaviors are incentive compatible. Cooperative game theory offers useful insights for assessing cooperative solutions for water conflicts in international river basins. Applying cooperative game theory concepts such as core, nucleolus, and Shapley value to Nile water conflicts, we examine the incentive structure of both cooperative and noncooperative strategies for different riparian countries and establish some baseline conditions for incentive-compatible cooperation in the Nile basin.

  8. Thermal contraction and flexure of intracratonic basins: A three dimensional study of the Michigan Basin

    NASA Astrophysics Data System (ADS)

    Nunn, J. A.

    1981-01-01

    Surface cooling of heated continental crust imposes a load on the lithosphere which subsides as the basement rocks contract. Accumulation of sediments in the resulting depression forms a sedimentary basin. Studies of the geometry of sedimentary basins with horizontal dimensions of a few hundred kilometers suggests the lithosphere responds to loads by regional flexure of a strong elastic or viscoelastic upper lithosphere. Two and three dimensional models for flexure of the lithosphere due to thermal contraction were applied to the Michigan basin. Lithostratigraphic data were used to quantitatively determine the contribution of the weight of sediment overburden to the subsidence. Thermal contraction load was calculated from the load necessary to produce the observed deflection of the lithosphere minus sediment load. Gravity effects of the models were computed and compared to the observed free air gravity anomalies.

  9. Impact melts of the Orientale and Imbrium basins

    NASA Astrophysics Data System (ADS)

    Spudis, P.

    2014-12-01

    The largest impacts on the Moon - those that form the multi-ring basins - can produce thousands of cubic kilometers of melt. This melt is largely concentrated inside the basin, although some is ejected along with the clastic materials that make up the continuous ejecta blanket that surrounds basins. Impact melt is important because it contains information on the crustal target for basins as well as being the most suitable material to date basin-forming events. New geological mapping of the lunar Orientale and Imbrium impact basins has identified likely deposits of both types of impact melt. The Orientale basin (930 km diameter) is well preserved and only partly flooded by later mare basalts. The basin interior melt sheet is represented by the Maunder Formation, a smooth-to-cracked surface unit that covers the innermost basin ring. Study of the composition of the Maunder Fm. as determined by remote sensing shows that it is remarkably uniform both laterally and vertically, with no evidence of differentiation. Surrounding the basin are vast ejecta deposits, most of which are probably made up of clastic material. However, a few isolated deposits contained within basin secondary craters appear melt-like, with low albedo and a cracked surface texture (e.g., Struve L, 20.7° N, 76° W). The larger (1160 km diameter) and slightly older Imbrium basin is mostly filled with mare basalt lava, concealing most of the basin floor. The Imbrium basin exterior shows isolated deposits of melt-like material in several locales, including on the floors of the craters Parrot C (18.5° S, 1.2° E) and Murchison (5.1° N, 0.1° W). These deposits have low albedo and show cracked surfaces, with evidence of ground flow after deposition. Their composition is remarkably similar to highland basaltic impact melts found in the Apollo collections, such as the Apollo 17 impact melts. These features offer the possibility of examining basin impact melt at distances far removed from basin interiors or

  10. Nuussuaq basin of west Greenland: Subsidence and structural inversion in an Albian - early Tertiary pull-apart basin

    SciTech Connect

    Tankard, A. ); Ng, T. ) Renner, T. )

    1996-01-01

    The western margin of Greenland consists of a complex of linked extensional basins which formed during opening of Labrador Sea and Baffin Bay in Albian - early Tertiary time. The Nuussuaq basin, which straddles Nuussuaq peninsula and Disko Island, is onshore. Its sedimentary succession is generally hidden beneath a cover of early Tertiary extrusives. Slim-hole exploration drilling has been based on an integrated basin analysis and magnetotelluric data acquisition. Nuussuaq basin developed at a left-lateral releasing stepover at the end of the Ungava fault, an interplate strike-slip fault zone. SW-directed extension was accommodated by several transfer faults which compartmented the Nuussuaq basin. Although the principal depocenter is only 1500 km[sup 2] in area, interpretation of the magnetotelluric: data shows basin depths greater than 10 km. Persistent overpressuring and the low resistivity lower basin fill are believed to be typical of a young basin which has subsided rapidly. The Cretaceous - lower Tertiary succession is indicative of a restricted, underfilled basin. In contrast, the mid-Paleocene paleogeography was controlled by dextral slip along the basement strike-slip fault zones, broadscale structural inversion of the earlier extensional faults, and widespread volcanism. Catastrophic crestal collapse of inversion anticlines is reflected in sudden incision and rapid filling of a suite of paleovalleys. In Paleocene time, the Nuussuag basin was generally overfilled and dominated by terrestrial depositional systems. Oil seeps are associated with crestal collapse and fracturing of inversion structures. Biomarkers suggest a source rock of Paleocene age.

  11. Nuussuaq basin of west Greenland: Subsidence and structural inversion in an Albian - early Tertiary pull-apart basin

    SciTech Connect

    Tankard, A.; Ng, T. Renner, T.

    1996-12-31

    The western margin of Greenland consists of a complex of linked extensional basins which formed during opening of Labrador Sea and Baffin Bay in Albian - early Tertiary time. The Nuussuaq basin, which straddles Nuussuaq peninsula and Disko Island, is onshore. Its sedimentary succession is generally hidden beneath a cover of early Tertiary extrusives. Slim-hole exploration drilling has been based on an integrated basin analysis and magnetotelluric data acquisition. Nuussuaq basin developed at a left-lateral releasing stepover at the end of the Ungava fault, an interplate strike-slip fault zone. SW-directed extension was accommodated by several transfer faults which compartmented the Nuussuaq basin. Although the principal depocenter is only 1500 km{sup 2} in area, interpretation of the magnetotelluric: data shows basin depths greater than 10 km. Persistent overpressuring and the low resistivity lower basin fill are believed to be typical of a young basin which has subsided rapidly. The Cretaceous - lower Tertiary succession is indicative of a restricted, underfilled basin. In contrast, the mid-Paleocene paleogeography was controlled by dextral slip along the basement strike-slip fault zones, broadscale structural inversion of the earlier extensional faults, and widespread volcanism. Catastrophic crestal collapse of inversion anticlines is reflected in sudden incision and rapid filling of a suite of paleovalleys. In Paleocene time, the Nuussuag basin was generally overfilled and dominated by terrestrial depositional systems. Oil seeps are associated with crestal collapse and fracturing of inversion structures. Biomarkers suggest a source rock of Paleocene age.

  12. Scaling issues in sustainable river basin management

    NASA Astrophysics Data System (ADS)

    Timmerman, Jos; Froebich, Jochen

    2014-05-01

    Sustainable river basin management implies considering the whole river basin when managing the water resources. Management measures target at dividing the water over different uses (nature, agriculture, industry, households) thereby avoiding calamities like having too much, too little or bad quality water. Water management measures are taken at the local level, usually considering the sub-national and sometimes national effects of such measures. A large part of the world's freshwater resources, however, is contained in river basins and groundwater systems that are shared by two or more countries. Sustainable river basin management consequently has to encompass local, regional, national and international scales. This requires coordination over and cooperation between these levels that is currently compressed into the term 'water governance' . Governance takes into account that a large number of stakeholders in different regimes (the principles, rules and procedures that steer management) contribute to policy and management of a resource. Governance includes the increasing importance of basically non-hierarchical modes of governing, where non-state actors (formal organizations like NGOs, private companies, consumer associations, etc.) participate in the formulation and implementation of public policy. Land use determines the run-off generation and use of irrigation water. Land use is increasingly determined by private sector initiatives at local scale. This is a complicating factor in the governance issue, as in comparison to former developments of large scale irrigation systems, planning institutions at state level have then less insight on actual water consumption. The water management regime of a basin consequently has to account for the different scales of water management and within these different scales with both state and non-state actors. The central elements of regimes include the policy setting (the policies and water management strategies), legal setting

  13. Onset of basin development in the Black Warrior Basin: Evidence from echinoderm biostratigraphy

    SciTech Connect

    Waters, J.A. . Dept. of Geology); Maples, C.G. )

    1992-01-01

    Many echinoderm taxa have limited temporal ranges and are potentially significant regional index fossils. Echinoderm endemism and size have limited the utility of echinoderms in biostratigraphy, but in particular situations, echinoderm biostratigraphy has provided the key to timing of geological events. One example is the timing of the onset of basin development in the Black Warrior Basin (BWB), a major Carboniferous foreland basin in Alabama and Mississippi. Physical stratigraphy indicates that basinal development in the BWB began some time during or after deposition of the Tuscumbia Limestone (TL). The TL was deposited on a broad carbonate platform on the southern passive margin of North America. In the BWB, the TL is overlain by the Pride Mountain Formation (PMF), which is a mixed siliciclastic/carbonate unit that prograded into the basin from the west. Northeast of the BWB, on the Warrior platform, the TL is Monteagle Limestone and the PMF have been difficult owing to the lack of biostratigraphic acuity in rocks of this age, which has resulted in mistaken time stratigraphic relationships between the units. The authors have collected echinoderms in the basal limestones in the PMF, which indicates a Gasperian age for all but the lowest 30 cm of the PMF. The Genevievian apparently was a time of nondeposition in the BWB because this lowermost 30 cm of PMF is temporally equivalent to tens of meters of carbonates rocks in the Monteagle Limestone on the Warrior platform. Therefore, the onset of foreland basin development in the BWB can be constrained to early during the Genevievian Stage.

  14. Subsidence history of Cook Inlet basin, southern Alaska: basement control on forearc basin development

    SciTech Connect

    Carroll, A.R.

    1987-05-01

    The Cook Inlet, lying between the Aleutian Trench and the Alaska-Aleutian batholith, has often been cited as a typical forearc basin. Upper (northeast) Cook Inlet Tertiary sediments have produced oil for over 25 years. Lower (southwest) Cook Inlet exploration, however, has been unsuccessful; previous studies have noted extensive zeolitization of potential Jurassic reservoirs. Geohistory analysis (backstripping) of published stratigraphic sections from outcrop and bore holes reveals two different tectonic mechanism of basin development in the lower and upper Cook Inlet. Thermal subsidence coincident with radiometrically determined cooling ages of the Alaska-Aleutian batholith predominated in the lower Cook Inlet during the Jurassic, suggesting that this part of the basin may be underlain by an extension of the batholith. Previous workers have noted a typical arc-unroofing sequence in Jurassic sandstones. The Tertiary section here is relatively thin. In contrast, the upper Cook Inlet has had a more complex history. Accumulation of nearly 5000, m of tertiary sediments over a thin Mesozoic section appears to have resulted from crustal loading, possibly through accretionary thickening of trenchward metasediments. These accreted terranes may extend beneath the upper Cook Inlet basin, resulting in a relatively ductile basement susceptible to load deformation. Published sandstone QFL compositions in the Tertiary indicate mixed or recycled orogene provenances, with source terrains both arcward and trenchward. Local basement type appears to have exerted a strong influence on sediment accumulation and petroleum potential in the Cook Inlet basin. Further study of the basin may thus lead to better understanding of the overall construction and tectonic history of this complex convergent margin.

  15. 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.

  16. Luminescence dating of ancient Darhad basin, Mongolia

    NASA Astrophysics Data System (ADS)

    Cheul Kim, Jin; Yi, Sangheon; Lim, Jaesoo; Kim, Ju-Yong

    2016-04-01

    Darhad basin is located in the northern Mongolia, in the western end of the Baikal Rift Zone. In contrast to the neighboring Lake Hovsgol, Mongolia's largest and deepest lake, the Darhad is a drained lake basin. It is ~100 km long (north-south), 20-40 km wide and covered by sediments which locally exceed 500 m thickness (Zorin et al., 1989). Darhad basin is characterized by alternating episodes of expansion and desiccation that are closely related with the Pleistocene damming events. Previous studies of the Darhad Basin suggest that the last paleolake was dammed by a large glacier or the sediments (Selivanov, 1967, 1968; Krivonogov et al., 2005; Gillespie et al., 2008). Especially, recent expansion of the paleolake might be caused by the two glacial maxima during MIS 4 and 2. However, glacier-dammed lakes might be short-lived, dried up and permafrost occurred in the drained basin during the Holocene period. The uppermost paleolake sediments (13.2 m depth) are exposed following the curvature of the meandering river (called "Hodon outcrop"). It is considered the most likely site for the youngest paleolake sediments because it is distributed in the northern middle part of the paleolake. Krivonogov et al. 2012 described the Hodon outcrop with the sedimentological and chronological data. Age dating of 16 samples (11 mollusk shells, 5 wood fragments) indicated that Hodon outcrop sediments were deposited between 10.1±7 and 4.9±5 ka. However, the ages obtained on shells much older dates than the matched wood samples because of ingestion of old carbon by mollusks. The age difference between shells and wood fragments is a minimum of 1.73 ka and a maximum of 3.41 ka (average 2.5 ka). In this case, 14C ages from shells should be corrected with appropriate correction factor. However, the old carbon effects could vary temperally and spatially in the Darhad paleolake. The limited number of the 14C ages from wood fragments result in a simple linear trend in the depth-age curve

  17. NATURAL GAS RESOURCES IN DEEP SEDIMENTARY BASINS

    SciTech Connect

    Thaddeus S. Dyman; Troy Cook; Robert A. Crovelli; Allison A. Henry; Timothy C. Hester; Ronald C. Johnson; Michael D. Lewan; Vito F. Nuccio; James W. Schmoker; Dennis B. Riggin; Christopher J. Schenk

    2002-02-05

    From a geological perspective, deep natural gas resources are generally defined as resources occurring in reservoirs at or below 15,000 feet, whereas ultra-deep gas occurs below 25,000 feet. From an operational point of view, ''deep'' is often thought of in a relative sense based on the geologic and engineering knowledge of gas (and oil) resources in a particular area. Deep gas can be found in either conventionally-trapped or unconventional basin-center accumulations that are essentially large single fields having spatial dimensions often exceeding those of conventional fields. Exploration for deep conventional and unconventional basin-center natural gas resources deserves special attention because these resources are widespread and occur in diverse geologic environments. In 1995, the U.S. Geological Survey estimated that 939 TCF of technically recoverable natural gas remained to be discovered or was part of reserve appreciation from known fields in the onshore areas and State waters of the United. Of this USGS resource, nearly 114 trillion cubic feet (Tcf) of technically-recoverable gas remains to be discovered from deep sedimentary basins. Worldwide estimates of deep gas are also high. The U.S. Geological Survey World Petroleum Assessment 2000 Project recently estimated a world mean undiscovered conventional gas resource outside the U.S. of 844 Tcf below 4.5 km (about 15,000 feet). Less is known about the origins of deep gas than about the origins of gas at shallower depths because fewer wells have been drilled into the deeper portions of many basins. Some of the many factors contributing to the origin of deep gas include the thermal stability of methane, the role of water and non-hydrocarbon gases in natural gas generation, porosity loss with increasing thermal maturity, the kinetics of deep gas generation, thermal cracking of oil to gas, and source rock potential based on thermal maturity and kerogen type. Recent experimental simulations using laboratory

  18. Early history of the Michigan basin: Subsidence and Appalachian tectonics

    SciTech Connect

    Howell, P.D.; van der Pluijm, B.A. )

    1990-12-01

    Geometries of Cambrian to Silurian stratigraphic sequences in the Michigan basin record discrete episodes of basin-centered subsidence separated by periods of regional tilting. Backstripping reveals irregular subsidence rates that argue against a simple thermal contraction model. Depositional facies architecture also reflects episodic subsidence patterns, basin-centered facies tracts dominating during subsidence reactivations. These three lines of evidence indicate that subsidence cessations and reactivations characterize the early history of the Michigan basin. Periods of episodic subsidence correlate temporally with orogenic events in the Appalachians, suggesting that reactivation of basin subsidence is related to tectonic activity. The authors propose that Appalachian orogenic activity caused the episodic subsidence of the Michigan basin, possibly through weakening of the lower crust and reactivation of a preexisting upper-crustal isotatic imbalance.

  19. Mining the earth's heat in the basin and range

    USGS Publications Warehouse

    Sass, John H.

    1995-01-01

    The Geothermal Program of the U.S. Geological Survey (USGS) is revisiting the Basin and Range Province after a hiatus of over a decade. The Basin and Range is a region of Neogene extension and generally high, but regionally and locally variable heat flow. The northern Basin and Range (Great Basin) has higher mean elevation and more intense Quaternary extension than does the southern Basin and Range, and a somewhat higher average heat flow. Present geothermal electric power generation (500+ MW) is entirely from hydrothermal systems of the Great Basin. The USGS is seeking industrial partners to investigate the potential for new hydrothermal reservoirs and to develop the technology to enhance the productivity of existing reservoirs.

  20. Early history of the Michigan basin: Subsidence and Appalachian tectonics

    NASA Astrophysics Data System (ADS)

    Howell, Paul D.; van der Pluijm, Ben A.

    1990-12-01

    Geometries of Cambrian to Silurian stratigraphc sequences in the Michigan basin record discrete episodes of basin-centered subsidence separated by periods of regional tilting. Backstripping reveals irregular subsidence rates that argue against a simple thermal contraction model. Depositional facies architecture also reflects episodic subsidence patterns, basin-centered facies tracts dominating during subsidence reactivations. These three lines of evidence indicate that subsidence cessations and reactivations characterize the early history of the Michigan basin. Periods of episodic subsidence correlate temporally with orogenic events in the Appalachians, suggesting that reactivation of basin subsidence is related to tectonic activity. We propose that Appalachian orogenic activity caused the episodic subsidence of the Michigan basin, possibly through weakening of the lower crust and reactivation of a preexisting upper-crustal isostatic imbalance.