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Sample records for platform basins ne

  1. Dating the Barremian-Aptian shallow platform deposits at the eastern part of the Kopet Dagh sedimentary basin, NE Iran

    NASA Astrophysics Data System (ADS)

    Chenarani, Atefeh; Hosseini, Seyedabolfazl; Vahidi Nia, Mohammad

    2016-04-01

    The Kopet Dagh sedimentary basin covers the northeastern part of Iran, most parts of Turkmenistan and north of Afghanistan which contains several giant gas fields. The extension of this basin in the Iranian part is around 55km2(Afshar Harb, 1994). The Kopet Dagh basin is marked by having very thick sedimentary rocks and lack of volcanic activity. During the Lower Cretaceous, the Tirgan Formation was deposited in a shallow platform setting and lithologically includes in thick-bedded orbitolinid limestones. This study focuses on the biostratigraphy and age determination of these shallow-water deposits using benthic foraminifera and calcareous green algae. In the studied outcrop, the Tirgan Formation has a thickness of 180 m and includes in limestone beds with some marly intervals. It is overlain by the Sarcheshmeh Formation and rests on the Shurijeh Formation. Both contacts are believed to be transitional and lack of discontinuity. A total of 56 thin-sections were used in this study. This study led to determine 28 genera and 14 species of benthic foraminifera along with 13 genera and 5 species of calcareous green algae. Based on the obtained biostratigraphy data, a late Barremian-early Aptian age is suggested for these deposits. We also defined the precise boundary between the Barremian and Aptian which is reported for the first time from this area. Keywords: Barremian-Aptian, Shallow platform, Kopet Dagh, Iran. Reference: Afshar Harb, A., 1994. Geology of Iran: Geology of the Kopet Dagh. Geological survey of Iran, Report No. 11, 275 pp.

  2. Controls on facies and sequence stratigraphy of an upper Miocene carbonate ramp and platform, Melilla basin, NE Morocco

    USGS Publications Warehouse

    Cunningham, K.J.; Collins, Luke S.

    2002-01-01

    Upwelling of cool seawater, paleoceanographic circulation, paleoclimate, local tectonics and relative sea-level change controlled the lithofacies and sequence stratigraphy of a carbonate ramp and overlying platform that are part of a temporally well constrained carbonate complex in the Melilla basin, northeastern Morocco. At Melilla, from oldest to youngest, a third-order depositional sequence within the carbonate complex contains (1) a retrogradational, transgressive, warm temperate-type rhodalgal ramp; (2) an early highstand, progradational, bioclastic platform composed mainly of a temperate-type, bivalve-rich molechfor facies; and (3) late highstand, progradational to downstepping, subtropical/tropical-type chlorozoan fringing Porites reefs. The change from rhodalgal ramp to molechfor platform occurred at 7.0??0.14 Ma near the Tortonian/Messinian boundary. During a late stage in the development of the bioclastic platform a transition from temperate-type molechfor facies to subtropical/tropical-type chlorozoan facies occurred and is bracketed by chron 3An.2n (??? 6.3-6.6 Ma). Comparison to a well-dated carbonate complex in southeastern Spain at Cabo de Gata suggests that upwelling of cool seawater influenced production of temperate-type limestone within the ramp and platform at Melilla during postulated late Tortonian-early Messinian subtropical/tropical paleoclimatic conditions in the western Paleo-Mediterranean region. The upwelling of cool seawater across the bioclastic platform at Melilla could be related to the beginning of 'siphoning' of deep, cold Atlantic waters into the Paleo-Mediterranean Sea at 7.17 Ma. The facies change within the bioclastic platform from molechfor to chlorozoan facies may be coincident with a reduction of the siphoning of Atlantic waters and the end of upwelling at Melilla during chron 3An.2n. The ramp contains one retrogradational parasequence and the bioclastic platform three progradational parasequences. Minor erosional surfaces

  3. Active Eruptions in the NE Lau Basin

    NASA Astrophysics Data System (ADS)

    Resing, J. A.; Embley, R. W.

    2009-12-01

    NE Lau Response Team: K Rubin, E Baker, J Lupton, M Lilley, T Shank, S Merle, R Dziak, T Collasius (Jason 2 Expedition Leader), N Buck, T Baumberger, D Butterfield, D Clague, D Conlin, J Cowen, R Davis, L Evans, J Huber, M Keith, N Keller, P Michael, E Podowski, A-L Reysenbach, K Roe, H Thomas, S Walker. During a May 2009 cruise to W Mata volcano in the NE Lau Basin, we made the first observations of an active eruption on the deep-sea floor. The cruise was organized after volcanic activity was detected at two sites (W Mata volcano and NE Lau Spreading Center, NELSC) during a Nov. 2008 NOAA-PMEL expedition. At that time, both sites had elevated H2 concentrations and volcaniclastic shards in the hydrothermal plumes. Moored hydrophone data since Jan 2009 indicate that the activity at W Mata has been continuous between these expeditions. Results of our cruise and other work suggest that the NE Lau Basin hosts an unusually high level of magmatic activity, making it an ideal location to study the effects of magmatic processes on hydrothermal activity and associated ecosystems. W Mata was visited with 5 ROV Jason 2 dives and 2 dives with the MBARI autonomous mapping vehicle in May 2009. It was actively erupting at the 1200 m deep summit during each, so a hydrophone was deployed locally to collect acoustic data. Ship and shore-based analysis of HD video, molten lava, rocks, sediments, hot spring waters, and micro- and macro biological specimens collected by Jason 2 have provided a wealth of data. The eruption itself was characterized by extrusion of red, molten lava, extensive degassing, formation of large magma bubbles, explosive pyroclast ejection, and the active extrusion of pillow lavas. The erupting magmas are boninite, a relatively rare magma type found only at convergent margins. The hydrothermal fluids are generally acidic and all diffuse fluids collected were microbially active, even those at pH <3. W Mata was host to shrimp similar to those found at several other

  4. NeXO Web: the NeXO ontology database and visualization platform

    PubMed Central

    Dutkowski, Janusz; Ono, Keiichiro; Kramer, Michael; Yu, Michael; Pratt, Dexter; Demchak, Barry; Ideker, Trey

    2014-01-01

    The Network-extracted Ontology (NeXO) is a gene ontology inferred directly from large-scale molecular networks. While most ontologies are constructed through manual expert curation, NeXO uses a principled computational approach which integrates evidence from hundreds of thousands of individual gene and protein interactions to construct a global hierarchy of cellular components and processes. Here, we describe the development of the NeXO Web platform (http://www.nexontology.org)—an online database and graphical user interface for visualizing, browsing and performing term enrichment analysis using NeXO and the gene ontology. The platform applies state-of-the-art web technology and visualization techniques to provide an intuitive framework for investigating biological machinery captured by both data-driven and manually curated ontologies. PMID:24271398

  5. neXtProt: a knowledge platform for human proteins.

    PubMed

    Lane, Lydie; Argoud-Puy, Ghislaine; Britan, Aurore; Cusin, Isabelle; Duek, Paula D; Evalet, Olivier; Gateau, Alain; Gaudet, Pascale; Gleizes, Anne; Masselot, Alexandre; Zwahlen, Catherine; Bairoch, Amos

    2012-01-01

    neXtProt (http://www.nextprot.org/) is a new human protein-centric knowledge platform. Developed at the Swiss Institute of Bioinformatics (SIB), it aims to help researchers answer questions relevant to human proteins. To achieve this goal, neXtProt is built on a corpus containing both curated knowledge originating from the UniProtKB/Swiss-Prot knowledgebase and carefully selected and filtered high-throughput data pertinent to human proteins. This article presents an overview of the database and the data integration process. We also lay out the key future directions of neXtProt that we consider the necessary steps to make neXtProt the one-stop-shop for all research projects focusing on human proteins. PMID:22139911

  6. neXtProt: a knowledge platform for human proteins

    PubMed Central

    Lane, Lydie; Argoud-Puy, Ghislaine; Britan, Aurore; Cusin, Isabelle; Duek, Paula D.; Evalet, Olivier; Gateau, Alain; Gaudet, Pascale; Gleizes, Anne; Masselot, Alexandre; Zwahlen, Catherine; Bairoch, Amos

    2012-01-01

    neXtProt (http://www.nextprot.org/) is a new human protein-centric knowledge platform. Developed at the Swiss Institute of Bioinformatics (SIB), it aims to help researchers answer questions relevant to human proteins. To achieve this goal, neXtProt is built on a corpus containing both curated knowledge originating from the UniProtKB/Swiss-Prot knowledgebase and carefully selected and filtered high-throughput data pertinent to human proteins. This article presents an overview of the database and the data integration process. We also lay out the key future directions of neXtProt that we consider the necessary steps to make neXtProt the one-stop-shop for all research projects focusing on human proteins. PMID:22139911

  7. Plateau growth around the Changma Basin in NE Tibet

    NASA Astrophysics Data System (ADS)

    Vernon, Rowan; Cunningham, Dickson; Zhang, Jin; England, Richard

    2014-05-01

    The Qilian Mountains form one of the most actively uplifting regions of the northeastern Tibetan Plateau and provide an opportunity to study the ongoing, intermediate stages of plateau growth. The crust of the Qilian Mountains consists of an orogenic collage of mid-Proterozoic to mid-Palaeozoic island arc terranes accreted to the North China Craton during the Palaeozoic. NE-directed compression related to the Indo-Asian collision began in the Early Neogene, uplifting fold-thrust mountain ranges which splay south-eastwards from the sinistral northeast-trending Altyn Tagh Fault (ATF). In this study, we investigate the post-Oligocene tectonic evolution of the northern margin of the Tibetan Plateau around the Changma Basin, at the very northeast corner of the Plateau, where the ATF forms a triple junction with the frontal Qilian Shan thrust. Our research involves synthesis of previous geological and geophysical data, remote sensing analysis and field mapping of structures along key transects. The Changma Basin is a relatively low intra-montane basin in the northeast Tibetan Plateau that is receiving alluvial infill from surrounding ranges, but is also being drained by the Su Le River, one of the largest river systems in the northeast Tibetan Plateau. The basin is also internally deforming and inverting along fault and fold zones, as well as being overthrust along some of its margins. Where older basement trends are parallel to neotectonic faults, some reactivation is inferred and locally documented through field observations. Otherwise, the post-Oligocene thrust and oblique-slip faults which are responsible for uplifting various basement blocks and inverting the Changma Basin appear discordant to nearby basement trends. Range-bounding thrust faults with the greatest along-strike continuity and relief generation are assumed to have the largest displacements, whereas other intra-range thrusts that bound uplifted limestone blocks are assumed to have lower amounts of

  8. Hydrothermal plumes in the NE Lau basin: A regional perspective

    NASA Astrophysics Data System (ADS)

    Walker, S. L.; Baker, E. T.

    2013-12-01

    Exploration for mineral resources and the presence of an extensive plume of excess 3He centered at 1750 m water depth in the Samoa-Tonga-Fiji region (Lupton, 2004) have motivated exploration for active hydrothermal vent sites in the NE Lau basin during the past decade. The region is tectonically complex with back-arc spreading centers, rift zones, and volcanic centers, all of which potentially host active venting and/or active volcanism. To date, 400 km of the three back-arc spreading centers in the NE Lau basin (FRSC, Fonualei Rift and Spreading Center; MTJ, Mangatolu Triple Junction; and NELSC, Northeastern Lau Spreading Center) plus several volcanic centers have been systematically surveyed for hydrothermal plumes using towed CTD or MAPR arrays that include both optical backscatter and oxidation-reduction potential (ORP) sensors. The FRSC, where spreading rates range from 47 mm/a in the south to 85 mm/a in the north, has 5 active sites (plume depths ranging from 1300-2200 m) distributed one every ~40 km over its 200 km length. There is evidence for 4 active sites (plume depths range from 1950-2380 m) along the 150 km combined length of the MTJ segments, however plumes were optically weak (dNTU < 0.02) and except for one location along the northeastern limb, no ORP anomalies were detected. Plumes were observed off-axis to the MTJ at a bathymetric high adjacent to the northeastern limb (1700 m) as well as over the summit of a cratered volcanic edifice east of the central junction (1200-1300 m). The southern segment of the NELSC was the site of an active eruption in 2008 which injected event plumes throughout the water column (900-1600 m depth range) in addition to the chronic plume from the Maka massive sulfide vent site (1500 m). There is evidence for at least two additional active areas along the northern segments of the NELSC (1800-1900 m). Several volcanoes in the region are hydrothermally active ranging from the northernmost volcano on the Tonga arc (Niua

  9. 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

  10. Reefal platform development, Devonian of the Canning basin western Australia

    SciTech Connect

    Playford, P.E.; Hurley, N.F.; Kerans, C.; Middleton, M.F.

    1987-05-01

    Growth of Devonian reefal limestone platforms on the Canning basin was nearly continuous from the late Givetian to the late Famennian. The earliest (Givetian and early Frasnian) platforms were low-relief banks; later Frasnian and Famennian platforms were normally reef rimmed, with high relief. Upright reef margins predominated in the Frasnian, with intervals of backstepping associated with widespread drowning and the development of pinnacle reefs. A brief emergence occurred at the Frasnian-Famennian boundary, and the succeeding Famennian platforms advanced basinward over equivalent marginal slope and basin facies. Platform extinction in the late Famennian resulted from abrupt drowning. An important initial control on platform trends was basement topography resulting from Middle Devonian or older faulting. Continued faulting during the Late Devonian influenced the morphology of some platforms. Contemporary seismicity also led to neptunian fracturing and the collapse of platform margins. The hypothetical sea level curve for the Canning basin Devonian is believed to be a combined result of global eustatism and regional diastrophism; it shows gross resemblance to the equivalent Euramerican curve. Rates of sea level rise (or subsidence) are thought to have largely controlled platform evolution. Banks and advancing platforms were associated with slow rises in sea level; upright reef scarps with moderately rapid rises; and backstepping, pinnacle reefs, and drowning with very rapid rises. Shoaling-upward cycles in back-reef limestones resulted from periodic abrupt rises of a few meters, followed by longer stillstands. Seismic-stratigraphic modeling together with observed seismic records and well data suggest that the evolutionary model for the Devonian platforms deduced from outcrop studies can also be applied in the subsurface.

  11. Discontinuous Drainage Systems of NE Hellas Basin, Mars

    NASA Astrophysics Data System (ADS)

    Hargitai, H. I.; Gulick, V. C.

    2015-12-01

    We mapped several valley and channel systems located on the plains NE of Hellas Basin, NW of Dao, Harmakhis, and Reull Valles, using CTX, THEMIS, HiRISE and HRSC data. The dissected terrain is comprised of early Hesperian lava flows. Drainage systems consist of deep, narrow valleys that we interpret as bedrock reaches and small outflow-like, flat-floored channels, that are approximately 1-2 km wide and contain depositional bedforms. In these systems, approximately 130 m deep narrow reaches alternate with wide, shallow sediment-dominated reaches. This morphologic pattern is probably the result downcutting and erosion of bedrock by stream flow and subsequent deposition of the eroded material in the wider reaches downstream in response to local topographic and lithologic changes. The floors of the wider channel reaches contain several stream-lined smooth-surfaced islands, which we interpret as possible bar deposits. In some of these non-terminal depositional reaches, the channels are completely filled by deposits but further downstream the boundaries of the channel walls become apparent again. We interpret these locations as possible sites where stream flow spreads out and infiltrates into the subsurface and then subsequently outflows again to surface where channel walls become more defined. Some channels seem to be associated with the pitted latitude dependent mantle, whereas elevated islands remain smooth and free of pits. In the upper reaches of one channel system, an assemblage of intra-channel features is repeated: knobs, sinuous ridges and elongate, channel-jamming deposits similar to the morphology resulting from glaciers or rock glaciers. One channel system begins with several theater-shaped heads, suggesting a possible formation by sapping. Channel heads are cut into a high-thermal-inertia unit, possibly basaltic bedrock. We propose that this setting is suggestive of terrestrial discontinuous ephemeral stream channel systems.

  12. Wolfcampian sequence stratigraphy of eastern Central Basin platform, Texas

    SciTech Connect

    Candelaria, M.P.; Entzminger, D.J.; Behnken, F.H. ); Sarg, J.F. ); Wilde, G.L. )

    1992-04-01

    Integrated study of well logs, cores, high-resolution seismic data, and biostratigraphy has established the sequence framework of the Atokan (Early Pennsylvanian)-Wolfcampian (Early Permian) stratigraphic section along the eastern margin of the Central Basin platform in the Permian basin. Sequence interpretation of high-resolution, high-fold seismic data through this stratigraphic interval has revealed a complex progradational/retrogradational evolution of the platform margin that has demonstrated overall progradation of at least 12 km during early-middle Wolfcampian. Sequence stratigraphic study of the Wolfcamp interval has revealed details of the internal architecture and morphologic evolution of the contemporaneous platform margin. Two generalized seismic facies assemblages are recognized in the Wolfcampian. Platform interior facies are characterized by high-amplitude, laterally continuous parallel reflections; platform margin facies consist of progradational sigmoidal to oblique clinoforms and are characterized by discontinuous, low-amplitude reflections. Sequence interpretation of carbonate platform-to-basin strata geometries helps in predicting subtle stratigraphic trapping relationships and potential reservoir facies distribution. Moreover, this interpretive method assists in describing complex reservoir heterogeneities that can contribute to significant reserve additions from within existing fields.

  13. Basin evolution at the SW Barents Sea margin and its conjugate off NE Greenland

    NASA Astrophysics Data System (ADS)

    Faleide, Jan Inge; Wong, Po Wan; Helge Gabrielsen, Roy; Tsikalas, Filippos; Blaich, Olav A.; Planke, Sverre; Myklebust, Reidun

    2015-04-01

    The SW Barents Sea margin developed from a megashear zone which linked the Norwegian-Greenland Sea and the Artic Eurasia Basin during the initial Eocene opening. Within the dextral megashear system, a series of deep and narrow basins formed in the SW Barents Sea. These basins formed in response to multiple rift events and rapid differential subsidence. The distribution of salt structures both in the SW Barents Sea and on the conjugate NE Greenland margin reflects the Late Paleozoic basin configuration. Late Middle Jurassic to Early Cretaceous rifting affected all deep basins in the SW Barents Sea (e.g., Bjørnøya, Tromsø, Harstad and Sørvestsnaget basins) as on the mid-Norwegian margin and the conjugate NE Greenland margin. Following rifting, a wide region subsided and was covered by thick Cretaceous strata. Late Cretaceous-Paleocene rifting between Norway and Greenland was taken up within the megashear zone and pull-apart basins formed in the SW Barents Sea and in the Wandel Sea Basin in NE Greenland. Contraction/inversion formed structural highs separating distinct Late Cretaceous depocenters that continued to subside rapidly. The rifting culminated in crustal breakup and accretion of oceanic crust near the Paleocene-Eocene transition. NE Atlantic breakup was accompanied by large-scale igneous activity, which also affected parts of the SW Barents Sea margin. The sheared Senja FZ margin is segmented, each segment having different structural styles reflecting a complex interplay between the geometry of the sheared margin segments and the opening direction. A continental sliver was also cut off the SW Barents Sea margin, now forming the Greenland Ridge which is a protrusion of the NE Greenland margin. The continent-ocean transition is confined within a narrow zone, bounded by a characteristic marginal high along the Senja Fracture Zone. During Eocene, the Harstad and southern Sørvestsnaget basins developed as narrow, elongated, en echelon basins landward of the

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

    SciTech Connect

    Purves, W.J. ); Ting, S.C. )

    1990-05-01

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

  15. Chronology of the Early Toarcian environmental crisis in the Lorraine Sub-Basin (NE Paris Basin)

    NASA Astrophysics Data System (ADS)

    Ruebsam, Wolfgang; Münzberger, Petra; Schwark, Lorenz

    2014-10-01

    Early Toarcian (Jurassic; ∼183 Ma) sediments recorded profound environmental changes, including mass extinction, global warming, marine transgression as well as widespread bottom water anoxia and organic matter accumulation on the Western Tethyan shelf. Enhanced organic matter accumulation was accompanied by a positive carbon isotope excursion (CIE) in pelagic carbonate, which marks the Toarcian Oceanic Anoxic Event. These environmental changes were accompanied by a major perturbation of the global carbon cycle, expressed by negative CIE, interrupting the positive trend. The duration of the carbon cycle perturbation is still debated, with estimates for the negative CIE range from ∼200 to ∼600 kyr. Here we present ultra high-resolution (<1 kyr) measurements of magnetic susceptibility and sediment color from a marine section located in the Lorraine Sub-Basin (NE Paris Basin) documenting Milankovitch-controlled fluctuations in depositional conditions that occurred superimposed onto the overall sea level evolution. Differences in the wavelength of the sedimentary cycles indicate variable sediment accumulation rates that mainly resulted from rapid sea level fluctuations. The most pronounced sea level rise that took place within the uppermost tenuicostatum zone resulted in a strong condensation of the basal Schistes Carton formation. Strong condensation can explain the discrepancy between durations previously calculated for the CIE placed at this stratigraphic interval. Our data support durations of ∼900 kyr and ∼600 kyr for the positive and negative CIE, respectively. The cyclostratigraphy-based timescale further proposes a duration of >555 kyr for the tenuicostatum zone and 1310 kyr for the serpentinum zone. The durations of the elegantulum and falciferum subzones can be estimated to ∼790 kyr and ∼520 kyr, respectively. A change in the orbital response from eccentricity- to obliquity-forcing, evident from other locations, is well-expressed in the Lorraine

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

    SciTech Connect

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

    1988-01-01

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

  17. Neogene Magnetostratigraphy of the Xunhua and Hualong Basins, NE Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Lease, R. O.; Hough, B.; Burbank, D.; Yuan, D.; Wang, Z.; Zheng, D.; Zhang, G.; Zheng, W.; Zhang, P.

    2006-12-01

    The Xunhua and Hualong intermontane basins in NE Tibet contain strata recording Mio-Pliocene surface uplift, deformation, and lateral expansion of the Tibetan Plateau. The timing and nature of broad surface uplift of the Tibetan Plateau remains uncertain. Competing interpretations argue for synchronous uplift of the entire plateau, pulsed plateau uplift, and incremental outward and upward plateau growth. Even within any given sector of the plateau, controversy prevails over whether the entire region rose synchronously or whether the growth of individual ranges and ponding of sediment in intervening basins led to incremental expansion and upward plateau growth. To address this question we aim to combine information from basin stratigraphy and provenance, chronology of deposition, stable isotopes, structural geometry, and cooling histories of bounding ranges to develop a more coherent synthesis of plateau growth in this region. The Xunhua and Hualong basins lie along the NE margin of the Tibetan Plateau, a broad, eastward-sloping topographic ramp punctuated by individual mountain ranges: locally, the W. Qinling Shan to the S, the Laji Shan to the N, the Jishi Shan to the E, and the Gongbo and Zamazari Shan to the W. The youngest (U-Th)/He cooling ages from these ranges are Late Miocene, suggesting accelerated rock uplift, erosion, and cooling at this time. Additionally, the Linxia basin to the E and the Guide basin to the W exhibit increased sediment- accumulation rates and grain size in the Late Miocene (Fang et al., 2003; 2005). Both the Xunhua and Hualong basins contain a coarsening-upward sequence of fine-grained, gypsiferous, lacustrine mudstone at the base that grade up-section into fluvial sandstone and siltstone (including numerous paleosols), with conglomerate capping the sequence. The homogeneity of the oldest strata in the Xunhua and Hualong basins suggests that the basins were initially contiguous. However, at present the significantly folded Hualong

  18. Tectonic implications deduced from drill cores in the Qaidam basin, NE Tibetan Plateau (Invited)

    NASA Astrophysics Data System (ADS)

    Appel, E.; Zhang, W.; Fang, X.; Song, C.; Setzer, F.; Herb, C.

    2013-12-01

    The Qaidam Basin is the largest intermontane basin of the NE Tibetan Plateau and an ideal place to study the paleoenvironmental evolution and erosion history related to tectonic activity and climate change. We studied two cores of lacustrine sediments drilled in the western basin within a distance of about 25 km, the 940 m deep SG-1 core in the Chahansilatu sub-depression and the 723 m deep SG-1b core in the Jianshan anticline. These cores comprise fine-grained lacustrine sediments and according to our magnetostratigraphic results span the ages of ~2.8-1.1 Ma (SG-1) and ~7.3-1.6 Ma (SG-1b). The proxy record reveals a long-term drying trend, and several proxy parameters can be matched with the marine oxygen isotope curve indicating a tie to global climate change. However, overlying trends and stepwise changes of average sediment accumulation rates (SAR) point towards an influence of tectonic processes. The results of average SARs of core SG-1b show three intervals with relatively higher values from the bottom (>7.3 Ma) to 6.0 Ma, between 5.2 and 4.2 Ma and between 3.6 and 2.6 Ma. These phases are in temporal agreement with the deposition of thick coarse-grained deposits in other parts of the Qaidam basin, the development of the en-echelon s-shaped structure of the basin, the separation of the western basin into shallow subbasins and the formation of a large synclinal trough in the eastern basin, and tectonic activities at the north-eastern plateau and other plateau regions. Growth strata are crucial to interpret the fold-and-thrust geometry, and the kinematics modeled by variations of the sedimentation rate and the uplift rate in the folding region. Several features indicate that the geometry of growth strata at our study site has developed by limb rotation with clear changes of growth strata dip and thicknesses on the forelimb, rather than by kink-band migration. Comparison of the SARs from SG-1 and SG-1b demonstrates that the development of the limb rotation was

  19. Integrated Analysis on Gravity and Magnetic Fields of the Hailar Basin, NE China: Implications for Basement Structure and Deep Tectonics

    NASA Astrophysics Data System (ADS)

    Sun, Bin; Wang, Liangshu; Dong, Ping; Wu, YongJing; Li, Changbo; Hu, Bo; Wang, Chong

    2012-11-01

    The Hailar Basin is one of the typical basins among the NE China Basin Groups, which is situated in the east of East Asia Orogene between the Siberia Plate and the North China Plate. Based on the detailed analysis of magnetic, gravity, petrophysical, geothermal and seismological data, we separate the Gravity and Magnetic Anomalies (GMA) into four orders using Wavelet Multi-scale Decomposition (WMD). The apparent depths of causative sources were then assessed by Power Spectrum Analysis (PSA) of each order. Low-order wavelet detail anomalies were used to study the basin's basement structure such as major faults, the basement lithology, uplifts and depressions. High-order ones were used for the inversion of Moho and Curie discontinuities using the Parker method. The results show that the Moho uplifting area of the Hailar Basin is located at the NE part of the basin, the Curie uplifting area is at the NW part, and neither of them is consistent with the basin's sedimentary center. This indicates that the Hailar Basin may differ in basin building pattern from other middle and eastern basins of the basin groups, and the Hailar Basin might be of a passive type. When the Pacific Plate was subducting to NE China, the frontier of the plate lying on the mantle transition zone didn't pass through the Great Khingan Mountains region, so there is not an obvious magma upwelling or lithospheric extension in the Hailar Basin area. Finally, based on the seismological data and results of WMD, a probable 2D crust model is derived from an across-basin profile using the 2D forward modeling of the Bouguer gravity anomaly. The results agree with those from seismic inversion, suggesting WMD is suitable for identifying major crustal density interfaces.

  20. Lower and middle Guadalupian shelf carbonates, eastern margin of Central Basin platform, Permian basin, west Texas

    SciTech Connect

    Ward, R.F.; Chalcraft, R.G.

    1988-01-01

    Lower and middle Guadalupian shelf carbonates serve as the reservoir for a nearly continuous band of oil fields extending 100 mi along the eastern margin of the Central Basin platform of west Texas. Approximately 5 billion bbl of oil have been produced from stratigraphic-structural traps within the Upper Permian (Gaudalupian Series) dolomites of the San Andrea and Grayburg Formations in Upton, Crane, Ector, Pecos, and Andrews Counties, Texas. The San Andrea and Grayburg Formations are cyclical shallowing-upward carbonate sequences of open shelf through sabkha facies whose depositional strike parallels the eastern margin of the Central Basin platform. Porosity and permeability of reservoir rock are governed by diagenetic processes such as dolomitization, anhydrite porosity occlusion, leaching, silicification, and authigenic clay formation. Self sediments are primarily burrowed wackestones and packstones that locally contain pelletal, skeletal, and ooid grainstones. Typical subtidal shelf sediments are capped by algal-laminated dolomite, nodular anhydritic dolomite, and bedded anhydrite. The fauna is normally sparse and dominated by foraminifera and algae. Less common faunal components include pelecypods, crinoids, sponges, Bryozoa, brachiopods, gastropods, and coral that are associated with the development of small scattered patch reefs. Lowering the sea level during the early Guadalpian initiated basinward progradation of San Andres carbonate facies with hydrocarbon reservoirs best developed in shallow self fusulinid wackestones to packstone and oolitic grainstone. Reservoir dolomites of the Grayburg formation are present east of San Andres fields with optimal reservoir properties occurring near the San Andreas outer shelf margin.

  1. Magnetostratigraphic and radiometric constraints on salt formation in the Qaidam Basin, NE Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Wang, Jiuyi; Fang, Xiaomin; Appel, Erwin; Zhang, Weilin

    2013-10-01

    The Qaidam Basin is the largest Cenozoic intermontane basin within the northeast (NE) Tibetan Plateau. It contains large amounts of nonmarine evaporite deposits formed during the Pliocene-Quaternary. Even at present, extensive salt deposits dominated by halite and potash are formed by solar-driven concentration of brine water in the basin interior, making it the most important industrial base for potash exploitation in China. The formation of salt required an arid climatic, appropriate hydrological and tectonic setting through geologic times and will do so in the future. Studying the salt formation in the Qaidam Basin will enhance our understanding of processes driven by saline lake evolution, regional climate change, and tectonic movements, not only for the setting of the Tibetan Plateau. Reliable dating is crucial for assessing the time of salt formation in Qaidam Basin and the accumulation process, yet no comprehensive scientific studies have been reported on this important issue until now. In this paper, we critically review and compile magnetostratigraphic and radiometric studies of the salt-bearing strata within seven depressions of the basin. We find that the ages of salt formation are very different in these depressions: for the Dalangtan, Yiliping, Chahansilatu, and Kunteyi depressions, first salt deposits occurred at >3.90 ± 0.02 Ma, 2.88 ± 0.04 Ma, 2.24 ± 0.01 Ma and 1.18 ± 0.02 Ma, respectively. For the Mahai, Gasikule, and Qarhan, the ages of earliest salt formation are much younger i.e., 302 ± 56 ka, 608 ± 38 ka, and 54-24 ka, respectively. However, the result from Mahai has to be considered with caution. The variability of ages suggests an older salt-forming stage in the center of the western basin and a younger salt accumulation period along the basin margin. In a regional view, previous results from stratigraphy, sedimentology, geomorphology, and tectonic history allow us to conclude that the salt formation in the Qaidam Basin was probably

  2. Rapid Magmatic Rates Implied by Widespread Contemporaneous Magmatism in the NE Lau Basin

    NASA Astrophysics Data System (ADS)

    Rubin, K. H.; Embley, R. W.; Arculus, R. J.; Pyle, D. G.; Russo, C. J.

    2011-12-01

    The northern portion of the Lau Basin is the fastest opening backarc environment on Earth. The NE portion of this basin is characterized by numerous recently active volcanic centers that have erupted a diverse range of magma types over a relatively small spatial domain (see Embley et al., 2009, abstract V51D-1719). Roughly 20% of the sea floor in an area of 40 x 70km in the northeasternmost portion of the Basin is floored by high backscatter seafloor characterized by little to no sediment cover, as documented by near-bottom photographs, and recovery of relatively fresh lavas during dredging operations aboard the R/V Kilo Moana in 2010. Visual observations are consistent with ages of 100 to 1000 yrs for most of these lavas. This region includes two recently active volcanoes discovered in 2008 as well as numerous others, such as a series of 9 small, very closely spaced, hydrothermally-active, elongate volcanic edifices (the "Matas") near the east-west portion of the Tonga Trench with an average spacing of just 4 km between the summits. Dredging reveals that all the Matas are composed of fresh boninite or picrite. A large, ~140 km2 lava sheet composed of one or more lava flows emanates from ridges and scarps between Volcano "O" and West Mata. These predominantly lobate and pillowed flows are fresh, very glassy and nearly aphyric; given lava thicknesses in excess of 30m seen in collapsed lava ponds, total erupted volumes probably represent >4 km3 of erupted magma. Other features in the area, some of which are currently hydrothermally active, have erupted compositions ranging from basalt to dacite. The voluminous, geologically recent volcanic activity from a wide range of primarily extensional volcanic centers suggests that this portion of the highly dynamic NE Lau basin is experiencing chaotic and perhaps transient patterns of localized mantle upwelling capable of sampling and preserving a diverse range of mantle compositions and magma-forming conditions. The

  3. Extensive and Diverse Submarine Volcanism and Hydrothermal Activity in the NE Lau Basin

    NASA Astrophysics Data System (ADS)

    Embley, R. W.; Merle, S. G.; Lupton, J. E.; Resing, J.; Baker, E. T.; Lilley, M. D.; Arculus, R. J.; Crowhurst, P. V.

    2009-12-01

    The northeast Lau basin, the NE “corner” of the Tonga subduction zone, has an unusual concentration of young submarine volcanism and hydrothermal activity. The area is bounded on the west by overlapping spreading centers opening at rates up to 120 mm/yr, on the north by the E-W trending Tonga trench and on the east by the Tofua arc front. From the south, the Fonualei rift spreading center (FRSC) overlaps with the southern rift of The Mangatolo triple junction spreading center (MTJSC). The northern arm of the MTJSC overlaps with the northeast Lau spreading center (NELSC). Surveys of the area with an EM300 sonar system in November 2008 show high backscatter over the 10-20 km wide neovolcanic zones of the FRSC, MTJSC and NELSC. High backscatter is also associated with: (1) a 10-km diameter, hydrothermally active, volcanic caldera/cone (Volcano “O”) lying between the NELSC and the northern Tofua arc front; (2) a rift zone extending north from volcano “O” and intersecting the NELSC near the Tonga trench; and (3) a series of volcanoes constructed along SW-NE trending crustal tears in the northernmost backarc near the east-west portion of the Tonga Trench. Two eruptions were detected in November 2008 during hydrothermal plume surveys of the area. Subsequent dives with the remotely operated vehicle Jason 2 in May 2009 revealed that the southern NELSC eruption was a short-lived, primarily effusive eruption. The second eruption was detected on the summit of the largest SW-NE trending volcano (West Mata) and was ongoing when Jason 2 arrived on site more than 6 months later. It was producing both pillow lavas and abundant volcaniclastic debris streams that have a characteristic appearance on the sonar backscatter map. There is also an unusual series of lava flows emanating from ridges and scarps between Volcano “O” and West Mata. These flows contain drained-out lava ponds up to 2 km in diameter. The apparent high level of volcanic activity in the NE Lau basin

  4. The Neogene tectonic evolution and climatic change of the Tianshui Basin, NE Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Peng, T.; Li, J.; Song, C.; Zhao, Z.; Zhang, J.; Wang, X.; Hui, Z.

    2013-12-01

    The Tianshui Basin, located at the conjunction of NE Tibetan Plateau and Chinese Loess Plateau, has received intensive attention recently. Fine-grained Miocene sediment was identified as loess in its north part and this pushes the onset of Asian aridification into 22 Ma. However, our sedimentological, biomarker, pollen, diatom and mammalian fossils evidence propose that these sediments were suggested to be mudflat/distal fan and floodplain deposit instead of eolian deposit. So detailed tectonic background and climate reconstruction may illustrate the controversy and shed light on the tectonic, climate and ecology interactions. Here we report our integrated studies on the tectonic evolution, climate change and paleoecology reconstruction in the Tianshui basin. Based on the magnetostratigraphy and fossil mammal ages, sedimentological and detrital fission-track thermochronologic (DFT) analysis reveals four episodic tectonic uplift events occurred at ~20 Ma, ~14 Ma, ~9.2-7.4 Ma and ~3.6 Ma along the basin and its adjacent mountains. The timing of these activities at Western Qinling have been documented at many segments of the Tibetan Plateau, so most likely they were the remote response to the ongoing India-Asia collision. Pollen, mammalian fossils and biomarker data permit us to illustrate the paleoenvironment in the Tianshui Basin. During the period of ~17-10 Ma, the climate was generally warm-humid revealed by the broad-leaved forest and low Average Chain Length (ACL) values, when the Paltybelodon and Gomphotherium were roaming near an extensive aquatic setting. In addition, the observed Middle Miocene Climatic Optimum and Middle Miocene Climatic Transition events may be a terrestrial response to global climate changes. During the interval of ~10-6 Ma, the climate was relatively arid characterized by the rapid development of steppe and appearance of the Hipparion fauna, consistent with the biomarker proxy. Although the NE Tibetan Plateau experienced a phase of

  5. New characterization aspects of carbonate accumulation horizons in Chalky Champagne (NE of the Paris Basin, France)

    NASA Astrophysics Data System (ADS)

    Linoir, Damien; Thomachot-Schneider, Céline; Gommeaux, Maxime; Fronteau, Gilles; Barbin, Vincent

    2016-05-01

    The soil profiles of the Champagne area (NE of Paris Basin, France) occasionally show carbonate accumulation horizons (CAHs). From the top to the bottom, these soil profiles include a rendic leptosol horizon, a Quaternary cryoturbated paleosol (QCP), and a chalky substratum. The CAHs are located in the top part of the QCP. This study is aimed at highlighting the specific characteristics of CAHs compared to other soil profile horizons using geophysics, geochemistry, micromorphology, and mercury injection porosimetry. It is the first essential step for understanding the impact of CAHs on water transfers into the Champagne soil profiles. Our analyses show that Champagne CAHs are not systematically characterized by a typical induration unlike generally put forward in the regional literature. They are more porous and heterogeneous than their parent material (QCP). Carbonate accumulation horizons are also characterized by singular colorimetric parameters that are linked to their geochemical specific content, even if they bear a signature of the initial QCP before the pedogenic modification.

  6. Extensive hydrothermal activity in the NE Lau basin revealed by ROV dives

    NASA Astrophysics Data System (ADS)

    Embley, R. W.; Resing, J. A.; Tebo, B.; Baker, E. T.; Butterfield, D. A.; Chadwick, B.; Davis, R.; de Ronde, C. E. J.; Lilley, M. D.; Lupton, J. E.; Merle, S. G.; Rubin, K. H.; Shank, T. M.; Walker, S. L.; Arculus, R. J.; Bobbitt, A. M.; Buck, N. J.; Caratori Tontini, F.; Crowhurst, P. V.; Mitchell, E.; Olson, E. J.; Ratmeyer, V.; Richards, S.; Roe, K. K.; Kenner-Chavis, P.; Martinez-Lyons, A.; Sheehan, C.; Brian, R.

    2014-12-01

    Dives with the QUEST 4000 ROV (Remotely Operated Vehicle) in September 2012 discovered nine hydrothermal sites in the arc and rear-arc region of the NE Lau Basin in 1150 m to 2630 m depth. These sites, originally detected by water column and seafloor surveys conducted in 2008-2011, include: (1) a paired sulfur-rich/black smoker field on the summit of a tectonically deformed magmatic arc volcano (Niua), (2) fracture-controlled black smoker venting on several small en echelon seamounts (north Matas) that lie between the magmatic arc and the backarc spreading center and (3) a magmatic degassing site on the summit of a dacite cone within a large (~12 km diameter) caldera volcano (Niuatahi). Dives at West Mata Seamount, which was undergoing strombolian volcanic activity and effusive rift-zone eruptions from 2008 to 2010, revealed a dormant volcanic phase in September 2012, with continued low-temperature diffuse venting. The high-temperature venting is likely driven by magmatic heat indicative of underlying partial melt zones and/or melt pockets distributed through the region. The occurrence of the youngest known boninite eruptions on the Mata volcanoes is consistent with subduction fluid flux melting extending into the rear-arc zone. Extension related to the transition from subduction to strike-slip motion of the northern Tonga Arc over the active Subduction-Transform Edge Propagator (STEP) fault probably contributes to the enhanced volcanism/hydrothermal activity in the NE Lau Basin. Chemosynthetic ecosystems at these sites range from mostly motile, lower diversity ecosystems at the eruptive/magmatically-degassing sites to higher diversity ecosystems with less mobile faunal components at the black-smoker systems. The wide range of fluid chemistry, water depth and geologic settings of the hydrothermal systems in this area provides an intriguing template to study the interaction of hydrothermal fluid chemistry, chemosynthetic habitats and their geologic underpinning

  7. Hyperactive hydrothermal activity in the NE Lau basin revealed by ROV dives

    NASA Astrophysics Data System (ADS)

    Embley, R. W.; Resing, J. A.; Tebo, B.; Baker, E. T.; Butterfield, D. A.; Chadwick, B.; Davis, R.; de Ronde, C. E.; Lilley, M. D.; Lupton, J. E.; Merle, S. G.; Rubin, K. H.; Shank, T. M.; Walker, S. L.; Arculus, R. J.; Bobbitt, A. M.; Buck, N.; Caratori Tontini, F.; Crowhurst, P. V.; Mitchell, E.; Olson, E. J.; Ratmeyer, V.; Richards, S.; Roe, K. K.; Keener, P.; Martinez Lyons, A.; Sheehan, C.; Brian, R.

    2013-12-01

    Dives with the QUEST 4000 ROV (Remotely Operated Vehicle) in September 2012 discovered nine hydrothermal sites in the arc and rear-arc region of the NE Lau Basin in 1150 m to 2630 m depth. These sites, originally detected by water column and seafloor surveys conducted in 2008-2011, include: (1) a paired sulfur-rich/black smoker field on the summit of a tectonically deformed magmatic arc volcano (Niua), (2) fracture-controlled black smoker venting on several small en echelon seamounts (north Matas) that lie between the magmatic arc and the backarc spreading center and (3) a magmatic degassing site on the summit of a dacite cone within a large (~12 km diameter) caldera volcano (Niuatahi). Dives at West Mata Seamount, which was undergoing strombolian volcanic activity and effusive rift-zone eruptions from 2008 to 2010, revealed a dormant volcanic phase in September 2012, with continued low-temperature diffuse venting. The high-temperature venting is likely driven by magmatic heat indicative of underlying partial melt zones and/or melt pockets distributed through the region. The occurrence of the youngest known boninite eruptions on the Mata volcanoes is consistent with subduction fluid flux melting extending into the rear-arc zone. Extension related to the transition from subduction to strike-slip motion of the northern Tonga Arc over the active Subduction-Transform Edge Propagator (STEP) fault probably contributes to the enhanced volcanism/hydrothermal activity in the NE Lau Basin. Chemosynthetic ecosystems at these sites range from mostly motile, lower diversity ecosystems at the eruptive/magmatically-degassing sites to higher diversity ecosystems with less mobile faunal components at the black-smoker systems. The wide range of fluid chemistry, water depth and geologic settings of the hydrothermal systems in this area provides an intriguing template to study the interaction of hydrothermal fluid chemistry, chemosynthetic habitats and their geologic underpinning

  8. Managing the impact of climate change on the hydrology of the Gallocanta Basin, NE-Spain

    NASA Astrophysics Data System (ADS)

    Kuhn, N. J.

    2010-12-01

    The endorheic Gallocanta Basin represents an environment highly sensitive to climate change. Over the past 60 years, the Laguna de Gallocanta, an ephemeral lake situated in the centre of the Gallocanta basin, experienced a sequence of wet and dry phases. The lake and its surrounding wetlands are one of only a few bird sanctuaries left in NE-Spain for grey cranes on their annual migration from Scandinavia to northern Africa. Understanding the impact of climate change on basin hydrology is therefore of utmost importance for the appropriate management of the bird sanctuary. Changes in lake level are only weakly linked to annual rainfall, but strongly to individual events, with reaction times from hours to months after rainfall. Individual extreme event intensities as well as magnitudes affect lake level through both groundwater and surface runoff. In this study, the characteristics and frequencies of daily, event, monthly and bi-monthly rainfall over the past 60 years were analysed to assess the role of past, current and future rainfall characteristics for the lake level and its fluctuations. The results revealed a clear link between increased frequencies of high magnitude rainfall and phases of water filling in the Laguna de Gallocanta. In the middle of the 20th century, the rainfall recharge of groundwater appears to have been more important for lake level, while more recently the frequency of high magnitude rainfall and surface runoff has emerged as the dominant variable. In the Gallocanta Basin, climate change and the distinct and continuing land use change since Spain joined the EU in 1986 have created an environment that is in a more or less constant state of transition. This highlights two challenges faced by researchers involved in developing water management tools for the Gallocanta Basin in particular, but also other endorheic basins with sensitive and rapidly changing environments. Hydrologists have to understand the processes and the spatial and temporal

  9. Geologic Storage at the Basin Scale: Region-Based Basin Modeling, Powder River Basin (PRB), NE Wyoming and SE Montana

    NASA Astrophysics Data System (ADS)

    Melick, J. J.; Gardner, M. H.

    2008-12-01

    Carbon capture and storage from the over 2000 power plants is estimated at 3-5 GT/yr, which requires large- scale geologic storage of greenhouse gasses in sedimentary basins. Unfortunately, determination of basin scale storage capacity is currently based on oversimplified geologic models that are difficult to validate. Simplification involves reducing the number of geologic parameters incorporated into the model, modeling with large grid cells, and treatment of subsurface reservoirs as homogeneous media. The latter problem reflects the focus of current models on fluid and/or fluid-rock interactions rather than fluid movement and migration pathways. For example, homogeneous models over emphasize fluid behavior, like the buoyancy of super-critical CO2, and hence overestimate leakage rates. Fluid mixing and fluid-rock interactions cannot be assessed with models that only investigate these reactions at a human time scale. Preliminary and conservative estimates of the total pore volume for the PRB suggest 200 GT of supercritical CO2 can be stored in this typical onshore sedimentary basin. The connected pore volume (CPV) however is not included in this estimate. Geological characterization of the CPV relates subsurface storage units to the most prolific reservoir classes (RCs). The CPV, number of well penetrations, supercritical storage area, and potential leakage pathways characterize each RC. Within each RC, a hierarchy of stratigraphic cycles is populated with stationary sedimentation regions that control rock property distributions by correlating environment of deposition (EOD) to CPV. The degree to which CPV varies between RCs depends on the geology and attendant heterogeneity retained in the fluid flow model. Region-based modeling of the PRB incorporates 28000 wells correlated across a 70,000 Km2 area, 2 km thick on average. Within this basin, five of the most productive RCs were identified from production history and placed in a fourfold stratigraphic framework

  10. Cretaceous intracontinental rifting and post-rift inversion in NE Brazil: Insights from the Rio do Peixe Basin

    NASA Astrophysics Data System (ADS)

    Nogueira, Francisco C. C.; Marques, Fernando O.; Bezerra, Francisco H. R.; de Castro, David L.; Fuck, Reinhardt A.

    2015-03-01

    The breakup of Pangea in the Mesozoic placed the South American and African plates under horizontal extension, which triggered rifting and the formation of intracontinental basins in NE Brazil. The subsequent geodynamic evolution changed the forces acting upon the South American plate because of the simultaneous development of the Mid-Atlantic Ridge (MAR) and the Andes. The problem we address in this work is the effect of the changing stress field on intracontinental deformation in NE Brazil, and we used the intracontinental Rio do Peixe Basin (RPB) as case study. We used remote sensing, shuttle radar topography, geophysical data, and detailed structural geology to address this problem. Based on the integrated analysis of brittle deformation within the basin, at the basin boundaries, and in the host basement, we conclude the following: (1) In the Cretaceous, the Rio do Peixe Basin formed from an approximately NW-SE tension, as deduced from brittle deformation in sedimentary rocks within the RPB and bounding master faults. (2) Subsequently, the maximum compressive stress that acted upon the study area shifted from vertical to horizontal, and was oriented approximately ENE-WSW. The new compressive stress field inverted the RPB, which is recorded in the basin at all scales. (3) The inversion of the RPB is consistent with the stress field imposed by the MAR push (to the west) and the Andean push (to the east), which have kept the South American plate under ENE-WSW horizontal compression since the late Cretaceous.

  11. Hydrothermal Activity and its Chemical Characteristics in the NE Lau Basin

    NASA Astrophysics Data System (ADS)

    Resing, J. A.; Lilley, M. D.; Baker, E. T.; Lupton, J. E.; Embley, R. W.; Buck, N.; Walker, S. L.; Olson, E. J.; Dziak, R. P.; Baumberger, T.

    2010-12-01

    The NE Lau Basin is a magmatically robust area with an abundance of hydrothermal activity. We conducted exploratory research to the NE Lau Basin during three cruises to the area in November 2008, May 2009, and May 2010. We have found an unusual density of hydrothermal activity in the area bounded by the NE Lau Spreading Center (NELSC) and the Tongan Magmatic arc. Aside from the magmatic activity at the NELSC and the Tonga Arc, this area includes a area of crustal extension, where nine elongate volcanoes (The Matas) lie in a 25km arc extending into the Tonga trench with the summits from ˜1200m to ˜ 2700m depth and a large volcanic feature (Volcano “O”) which is characterized by a caldera >10km diameter with an emergent dome in its SE quadrant. Finally, the basin bounded by the Matas, the NELSC, and Volcano “O” contain many large lava flows with elevated acoustic backscatter suggesting a relatively young age. During the cruise in 2008, two ongoing eruptions were encountered in the region, one at the NELSC and another at W Mata volcano. These eruptions were later confirmed using the Jason II submersible in 2009. W Mata has been continuously erupting over the course of our observations. In addition to the eruption on the NELSC, hydrothermal activity was also observed at Maka and Tafu volcanoes, which are south and north of the eruptive area respectively. Observations of hydrothermal activity at two sites were made within the caldera at Volcano “O” and on the volcanic arc at two depths on Niua Volcano. The cruise in May 2010, revealed dense hydrothermal activity along the Mata chain where eight of the nine Mata volcanoes were hydrothermally active, including W Mata. Hydrothermal activity in this region is very sulfur rich as documented by large amounts of elemental sulfur at “O”, Niua, and seven of the Matas (elemental sulfur is inferred from light scatter and particulate matter color; analyses are pending), by acidic magmatic volatiles at”O” and

  12. Mesozoic carbonate-siliciclastic platform to basin systems of a South Tethyan margin (Egypt, East Mediterranean)

    NASA Astrophysics Data System (ADS)

    Tassy, Aurélie; Crouzy, Emmanuel; Gorini, Christian; Rubino, Jean-Loup

    2015-04-01

    The Mesozoïc Egyptian margin is the south margin of a remnant of the Neo-Tethys Ocean, at the African northern plate boundary. East Mediterranean basin developed during the late Triassic-Early Jurassic rifting with a NW-SE opening direction (Frizon de Lamotte et al., 2011). During Mesozoïc, Egypt margin was a transform margin with a NW-SE orientation of transform faults. In the Eastern Mediterranean basin, Mesozoïc margins are characterized by mixed carbonate-siliciclastics platforms where subsidence and eustacy are the main parameters controlling the facies distribution and geometries of the platform-to-basin transition. Geometries and facies on the platform-slope-basin system, today well constrained on the Levant area, where still poorly known on the Egyptian margin. Geometries and stratigraphic architecture of the Egyptian margin are revealed, thanks to a regional seismic and well data-base provided by an industrial-academic group (GRI, Total). The objective is to understand the sismostratigraphic architecture of the platform-slope-basin system in a key area from Western Desert to Nile delta and Levant margin. Mapping of the top Jurassic and top Cretaceous show seismic geomorphology of the margin, with the cartography of the hinge line from Western Desert to Sinaï. During the Jurassic, carbonate platform show a prograding profile and a distally thickening of the external platform, non-abrupt slope profiles, and palaeovalleys incisions. Since the Cretaceous, the aggrading and retrograding mixed carbonate-siliciclastic platform show an alternation of steep NW-SE oblique segments and distally steepened segments. These structures of the platform edge are strongly controlled by the inherited tethyan transform directions. Along the hinge line, embayments are interpreted as megaslides. The basin infilling is characterised by an alternation of chaotic seismic facies and high amplitude reflectors onlaping the paleoslopes. MTC deposits can mobilize thick sedimentary

  13. Extensive young dacite lava flows between boninite and BABB in a backarc setting: NE Lau Basin

    NASA Astrophysics Data System (ADS)

    Embley, R. W.; Rubin, K. H.

    2015-12-01

    Several hundred square kilometers of young dacite lava flows mapped by their high acoustic backscatter erupted in several batches in proximity to boninite and back-arc basin basalt (BABB) in the NE Lau Basin, the world's fastest opening back-arc region and a site proposed as a modern analogue in some ophiolite models. Where sampled, these lavas are aphyric, glassy dacites and are not associated with andesite extrusives (commonly observed elsewhere). Several flow fields occur on the flank of the large silicic Niuatahi seamount. Two of the largest lava fields and several smaller ones (~220 km2) erupted as far as 60 km north of Niuatahi. Their occurrence is likely controlled by crustal fractures from the long-term extension in this rear-arc region. Determining thickness of these flows is problematic, but relief of 30-100 m on flow fronts and in collapsed areas yields volume estimates as high as ~7-18 km3 for the northern group. The mean silica content of the largest and best sampled dacite flow field (LL-B) is 65.6 ±0.2%, a remarkably consistent composition for such an extensive flow (~140 km2). Camera tows show lower viscosity flow forms, including many anastomatosing pillow tubes and ropey surfaces, as well as endogenous domes, ridges and lobes (some with "crease-like" extrusion ridges, and inflated lobes with extrusion structures). An enigmatic 2 x 1.5 km, 30-m deep collapse depression could mark an eruption center for the LL-B flow field. Low viscosity flow morphologies on portions of LL-B and a nearby smaller flow field implies high effusion rates during some phases of the eruption(s), which in turn implies some combination of higher than normal liquidus temperature and high water content. Submarine dacite flows have been described in ancient sequences from the Archaean through the Miocene but this is the first modern occurrence of large volume submarine dacite flows. The volume of these young dacite flows implies the presence of large differentiated melt

  14. Influence of Mesozoic age structure on Miocene tectonic development in NE Anzoategui, Eastern Venezuela Basin

    SciTech Connect

    Sadler, P.; White, S.

    1996-08-01

    Structure within and surrounding the Quiamare-La Ceiba region, Eastern Venezuela Basin, is dominated by two major thrust fault systems. They were generated during Early-Middle Miocene time in response to oblique convergence of the Caribbean and South American plates. They are. respectively, the SE vergent NE-SW oriented Anaco fault system, and the SSE vergent ENE-WSW oriented Pirital fault system. The major structural feature associated with each fault system is a basement cored ramp anticline. New seismic data provides evidence that contributes to a better understanding of the sequence of tectonic development within and surrounding the Quiamare-La Ceiba region. Compressional structures in both the hanging wall and the footwall of the Pirital fault system appear to be inverted normal faults, that were previously active during Mesozoic time along the northern South America passive margin. A conjugate set of strike-slip faults is also present. They are oriented NNW-SSE, parallel to the Urica lineation, and SSW-NNE, respectively. A Mesozoic origin for these faults is suggested. Post-compressional relaxation during Plio-Pleistocene time resulted in the development of shallow, small scale normal faults. These normal faults appear to be localized by structural adjustments along the strike-slip fault sets. Existing oil and gas production within the Quiamare-La Ceiba region is from localized structural closures. Strike-slip faults dissect the prevailing structural grain, and may provide an additional hydrocarbon trapping mechanism.

  15. Eruptive modes and hiatus of volcanism at West Mata seamount, NE Lau basin: 1996-2012

    NASA Astrophysics Data System (ADS)

    Embley, Robert W.; Merle, Susan G.; Baker, Edward T.; Rubin, Kenneth H.; Lupton, John E.; Resing, Joseph A.; Dziak, Robert P.; Lilley, Marvin D.; Chadwick, William W.; Shank, T.; Greene, Ron; Walker, Sharon L.; Haxel, Joseph; Olson, Eric; Baumberger, Tamara

    2014-10-01

    present multiple lines of evidence for years to decade-long changes in the location and character of volcanic activity at West Mata seamount in the NE Lau basin over a 16 year period, and a hiatus in summit eruptions from early 2011 to at least September 2012. Boninite lava and pyroclasts were observed erupting from its summit in 2009, and hydroacoustic data from a succession of hydrophones moored nearby show near-continuous eruptive activity from January 2009 to early 2011. Successive differencing of seven multibeam bathymetric surveys of the volcano made in the 1996-2012 period reveals a pattern of extended constructional volcanism on the summit and northwest flank punctuated by eruptions along the volcano's WSW rift zone (WSWRZ). Away from the summit, the volumetrically largest eruption during the observational period occurred between May 2010 and November 2011 at ˜2920 m depth near the base of the WSWRZ. The (nearly) equally long ENE rift zone did not experience any volcanic activity during the 1996-2012 period. The cessation of summit volcanism recorded on the moored hydrophone was accompanied or followed by the formation of a small summit crater and a landslide on the eastern flank. Water column sensors, analysis of gas samples in the overlying hydrothermal plume and dives with a remotely operated vehicle in September 2012 confirmed that the summit eruption had ceased. Based on the historical eruption rates calculated using the bathymetric differencing technique, the volcano could be as young as several thousand years.

  16. Be-10 derived basin-wide erosion rates of Southern Qilian Shan, NE Tibet

    NASA Astrophysics Data System (ADS)

    Hu, K.; Fang, X.; Granger, D. E.; Zhao, Z.

    2013-12-01

    The actively uplifting Qilian Shan forms the northeastern margin of the Tibetan Plateau. The mountain range is bounded to the northeast by a thrust fault forming a 2 km-high mountain front over the Hexi Corridor basin, and to the southwest by a series of thrusts within an internally-drained elevated plateau that steps downwards into the Qaidam basin. The mountain range forms an important climatic boundary as well, where the East Asian Monsoon gives its way to Northern Hemisphere Westerlies. Understanding the interplay among active faulting, climate, and erosion in this region could be important for revealing the northeastern expansion and uplift of the Tibetan Plateau. Here we present 10Be derived catchment-wide erosion rates for a large area of the southern Qilian Shan. Our preliminary results show remarkably slow erosion rates ranging from~ 10 - 100 mm/ky,much slower than those reported for rivers draining the north Qilian Shan (ranging from 39-833 mm/ky) [Palumbo et al., 2011]. These results may suggest that catchments draining the mountain front experience relatively high precipitation and are eroding quickly, while catchments in the arid, internally-drained interior are isolated from base level fall and are eroding slowly. Moreover, our erosion rates may also suggest that the interior (southern) portions of the Qilian Shan are deforming more slowly than along the frontal thrust. This is consistent with the North Qilian Shan thrust accommodating most of the tectonic shortening in the mountain range, with shortening occurring at a slower rate in the interior. These data may suggest that low erosion rates (at least partially due to aridity) are promoting surface uplift of the Qilian Shan and Qaidam basin along the northeastern edge of the Tibetan Plateau. Additional samples are being processed from a variety of geologic and climatic settings that we hope will further elucidate patterns of erosion in the Qilian Shan region. Palumbo, L., R. Hetzel, M. Tao, and X

  17. Partitioned transpression in the Triassic Aghdarband basin: evidence for a Cimmerian deformation in NE IRAN:

    NASA Astrophysics Data System (ADS)

    Zanchi, Andrea; Zanchetta, Stefano; Balini, Marco; Ghassemi, Mohammad Reza

    2014-05-01

    The Lower-Middle Triassic Aghdarband Basin, NE Iran, consists of a strongly deformed arc-related marine succession deposited along the southern margin of Eurasia (Turan domain) in a highly mobile tectonic context. The marine deposits are unconformably covered by Upper Triassic continental beds, marking the Cimmerian collision of Iran with Eurasia. The Aghdarband Basin is a key-area for the study of the Cimmerian events, as the Triassic units were severely folded and thrust short time after the collision and were unconformably covered by the gently deformed Middle Jurassic succession which seals the Cimmerian structures. The Triassic deposits form a north-verging thrust stack interacting with an important left-lateral strike-slip shear zone exposed in the northernmost part of the basin. Transpressional structures as strike-slip faults and vertical folds are here associated with high angle reverse faults forming intricate positive flower structures. Systematic asymmetry of major and parasitic folds, as well as their geometrical features indicate that they generated in a left-lateral transpressional regime roughly coeval to thrust imbrication to the south, as a consequence of a marked strain partitioning. Aim of this presentation is to describe in detail the deformational structures of the Aghdarband region, based on structural mapping and detailed original mesoscopic field analyses, resuming from the excellent work performed in the '70s by Ruttner (1991). Our work is focused on the pre mid-Jurassic structures which can be related to the final stages of the Cimmerian deformation resulting from the oblique collision of the Iranian microplate with the southern margin of Eurasia, the so-called Turan domain. We will finally discuss the kinematic significance of the Late Triassic oblique convergence zone of Aghdarband in the frame of strain partitioning in transpressional deformation. Structural weakness favouring strain partitioning can be related to inversion of syn

  18. Gravity and magnetic joint modeling of the Potiguar Rift Basin (NE Brazil): Basement control during Neocomian extension and deformation

    NASA Astrophysics Data System (ADS)

    Lopes de Castro, David

    2011-03-01

    A 2.5D gravity and magnetic investigation was conducted along five transects across the Potiguar Basin in the Borborema Province, NE Brazil. The objective of the study is to model the internal architecture of this intracontinental rift basin, which represents the interaction between the heterogeneous Precambrian basement and the Neocomian extensional tectonics, which led to the South Atlantic opening. Joint modeling of the gravity and magnetic data was constrained by Euler deconvolution results, seismic data, well logs and geologic mapping. This integrated approach allowed to determine the rift architecture that is inserted in a complex tectonic and structural framework. Results from joint modeling show that a series of asymmetric half-grabens is oriented in the NE-SW direction and controlled by a system of normal faults with throw greater than 5.5 km. High-density and low-magnetized material constitutes the footwall and intrarift horsts. These supracrustal heterogeneities in association with preexisting shear zones probably guided the Mesozoic rifting process in NE Brazil. Their composition seems to be related to metamorphic rocks of the Proterozoic basement, as suggested by gravity and magnetic anomalies and the geology of the exposed basement. Our interpretation is supported by geophysical studies carried out in the Benue Trough, the counterpart of the Potiguar Basin in West Africa.

  19. Identification and Implications of a Submarine Monogenetic Field in the NE Lau Basin

    NASA Astrophysics Data System (ADS)

    Rubin, K. H.; Embley, R. W.

    2012-12-01

    Short-lived, volcanism at discrete, closely spaced volcanic cones and low lying lava flows in the NE corner of the Lau backarc basin shares many characteristics with subaerial monogenetic fields. We use geological, morphological, petrological, and geochemical observations of this volcanic field made on five research expeditions since 2008, along with comparisons to well-known terrestrial monogenetic fields to assess whether the Mata volcanic group is best thought of as a submarine mongenetic volcanic field (a term rarely, if ever, applied to submarine settings). The volcanism has constructed a series of 9 small, very closely spaced, hydrothermally-active, elongate volcanic edifices near the east-west portion of the Tonga Trench, which are 1.5 to 7.5 km apart (summit to summit) and are 450 to 1400m tall. Only one of the volcanoes (West Mata) is currently active, erupting boninite pillow lavas along with explosively-generated volcaniclastic sediments. The ages of the youngest volcanics on the other Mata volcanoes are not yet determined but most are hydrothermally active and are surfaced with relatively young lava flows without significant sediment cover. The volcanoes are all formed predominantly of low effusion rate pillow lavas with variable amounts of pyroclastic deposits mantling the constructional topography, suggesting relatively long-lived volcanism (ca 100-200 yrs) at each center, similar to large lava shields in Iceland (e.g., skjaldbreidur). Detailed stratigraphic observations are as yet only available for one volcano (with more to come during an ROV field campaign in Sept. 2012). Bottom photographs provide no clear evidence for long-lived hiatuses at any of these cones and bathymetric data do not intricate overlapping constructional structures, resurgent construction, or large scale collapse or mass wasting structures, as might be expected for a protracted, many-eruption volcanic history at any single volcano. However, the oldest edifice does show evidence

  20. Timing and recurrence of failure within NE Gela Basin, Sicily Channel

    NASA Astrophysics Data System (ADS)

    Kuhlmann, Jannis; Asioli, Alessandra; Trincardi, Fabio; Huhn, Katrin

    2014-05-01

    Submarine mass movements represent a common phenomenon in the evolution of continental margins. In order to enhance knowledge on trigger mechanisms and assess the geologic risk of slope failure, many studies focus on extensive and voluminous slide complexes, since these may have catastrophic and largely unpredictable consequences for offshore infrastructures and coastal communities alike. However, rather thick and complex deposits often hinder the definition of internal structures and hence the recognition of individual failure events. Small-scaled slide complexes are uniquely positioned in this context, as full data coverage often allows for a more detailed evaluation of the timing and recurrence rates of failure. We present evidence from a multidisciplinary study combining high-resolution acoustic data with deep-drilled core material (MeBo type) from a prominent example - the NE portion of Gela Basin within Sicily Channel, Central Mediterranean Sea. Morphological data (Kongsberg Simrad EM120 and EM1002 multibeam echosounder) and subsurface imagery (Atlas parametric sediment echosounder) from this submarine landslide complex between 200 and 700 m water depth reveal multiple slope failures and stacked mass transport deposits of varying thicknesses and lateral distributions. Correlations of the acoustic data to 14C-dated core material (GeoB14401, 35.5 mbsf) drilled through the stacked mass transport deposits suggest the occurrence of four major failure events within the basin during the last ~30 ka. Failure times of these events relate to different palaeo-environments including (1) the MIS2/3 boundary, (2) the Last Glacial Maximum [LGM], (3) the deposition of Sapropel S1 equivalent, and (4) the late Holocene. In addition to these major events, the occasional presence of reworked shelf-benthic foraminifera species within the core sedimentary record hints towards the presence of additional, small-scaled events during the period of the LGM chronozone. Frequent failure

  1. Nanometer-Scale Pore Characteristics of Lacustrine Shale, Songliao Basin, NE China

    PubMed Central

    Wang, Min; Yang, Jinxiu; Wang, Zhiwei; Lu, Shuangfang

    2015-01-01

    In shale, liquid hydrocarbons are accumulated mainly in nanometer-scale pores or fractures, so the pore types and PSDs (pore size distributions) play a major role in the shale oil occurrence (free or absorbed state), amount of oil, and flow features. The pore types and PSDs of marine shale have been well studied; however, research on lacustrine shale is rare, especially for shale in the oil generation window, although lacustrine shale is deposited widely around the world. To investigate the relationship between nanometer-scale pores and oil occurrence in the lacustrine shale, 10 lacustrine shale core samples from Songliao Basin, NE China were analyzed. Analyses of these samples included geochemical measurements, SEM (scanning electron microscope) observations, low pressure CO2 and N2 adsorption, and high-pressure mercury injection experiments. Analysis results indicate that: (1) Pore types in the lacustrine shale include inter-matrix pores, intergranular pores, organic matter pores, and dissolution pores, and these pores are dominated by mesopores and micropores; (2) There is no apparent correlation between pore volumes and clay content, however, a weak negative correlation is present between total pore volume and carbonate content; (3) Pores in lacustrine shale are well developed when the organic matter maturity (Ro) is >1.0% and the pore volume is positively correlated with the TOC (total organic carbon) content. The statistical results suggest that oil in lacustrine shale mainly occurs in pores with diameters larger than 40 nm. However, more research is needed to determine whether this minimum pore diameter for oil occurrence in lacustrine shale is widely applicable. PMID:26285123

  2. Nanometer-Scale Pore Characteristics of Lacustrine Shale, Songliao Basin, NE China.

    PubMed

    Wang, Min; Yang, Jinxiu; Wang, Zhiwei; Lu, Shuangfang

    2015-01-01

    In shale, liquid hydrocarbons are accumulated mainly in nanometer-scale pores or fractures, so the pore types and PSDs (pore size distributions) play a major role in the shale oil occurrence (free or absorbed state), amount of oil, and flow features. The pore types and PSDs of marine shale have been well studied; however, research on lacustrine shale is rare, especially for shale in the oil generation window, although lacustrine shale is deposited widely around the world. To investigate the relationship between nanometer-scale pores and oil occurrence in the lacustrine shale, 10 lacustrine shale core samples from Songliao Basin, NE China were analyzed. Analyses of these samples included geochemical measurements, SEM (scanning electron microscope) observations, low pressure CO2 and N2 adsorption, and high-pressure mercury injection experiments. Analysis results indicate that: (1) Pore types in the lacustrine shale include inter-matrix pores, intergranular pores, organic matter pores, and dissolution pores, and these pores are dominated by mesopores and micropores; (2) There is no apparent correlation between pore volumes and clay content, however, a weak negative correlation is present between total pore volume and carbonate content; (3) Pores in lacustrine shale are well developed when the organic matter maturity (Ro) is >1.0% and the pore volume is positively correlated with the TOC (total organic carbon) content. The statistical results suggest that oil in lacustrine shale mainly occurs in pores with diameters larger than 40 nm. However, more research is needed to determine whether this minimum pore diameter for oil occurrence in lacustrine shale is widely applicable. PMID:26285123

  3. The massive dolomitization of platformal and basinal sequences: proposed models from the Paleocene, Northeast Sirte Basin, Libya

    NASA Astrophysics Data System (ADS)

    Mresah, Mohamed H.

    1998-03-01

    The Paleocene carbonate succession in the Northeast Sirte Basin is composed of two shallowing-upward ramp cycles, where each cycle is under- and overlain by deeper-water, pelagic facies. A significant proportion of each of these two cycles is dolomitized. Petrographic study, supported by geochemical data (stoichiometry, stable isotopes, trace elements, and fluid inclusions), and integrated with broader tectono-sedimentary information, has provided the basis for interpreting these Paleocene dolomites. The use of this integrated approach in the study of dolomites suggests that, despite the much publicized uncertainties in interpreting geochemical analyses of ancient dolomites, the results of the Paleocene dolomites show that the geochemical characteristics are generally consistent with regional stratigraphic distribution and petrographic observations. Four distinct types of dolomite have been recognized in this part of the Sirte Basin. Based on the stratigraphic position and petrographic criteria, two of these types have a platformal setting and the other two are basinal. The platform varieties consist of dolomicrites and pervasive stratal dolomites. The dolomicrites, interpreted to be of syn-sedimentary origin, were probably a product of reflux of seawater, with elevated salinity, as suggested by palaeoenvironmental analysis and supported by geochemical evidence (the average S'80 value is -0.1‰ PDB; the average Sr content is 639 ppm). The pervasive dolomites were formed during the progradation of the platform sequences, and probably stabilized and augmented during shallow burial. A meteoric-marine mixing-zone is thought to have been the most likely process for the formation of these dolomites. This interpretation is supported by geochemical evidence (the average δ18O is -2.4‰ PDB; the average Sr content is 72 ppm) combined with a favourable stratigraphic position. The most characteristic feature related to both mixing-zone and reflux dolomitization is the

  4. Carbonate platform, slope, and basinal deposits of Upper Oligocene, Kalimantan, Indonesia

    SciTech Connect

    Armin, R.A.; Cutler, W.G.; Mahadi, S.; Van de Weerd, A.

    1987-05-01

    Upper Oligocene platform carbonates (Berai Formation) occur extensively on the Barito shelf in southeastern Kalimantan (Borneo) and are flanked northward by coeval slope and basinal deposits (Bongan Formation) which accumulated in the southwestern part of the Kutei basin. Isolated carbonate buildups equivalent to the Berai Formation also occur within the Kutei basin and were probably deposited on basement highs. The distribution of these facies is fairly well constrained by the study of outcrops, wells, and seismic profiles. The Berai Formation consists of diverse limestone types with a wide range of textures and with dominant skeletal components of large foraminifera, red algae, and corals. Deposition of the Berai Formation occurred in moderate- and high-energy shallow-marine conditions. Slope and basin facies occur in extensional basins adjacent to the shelfal carbonates and peripheral to isolated carbonate buildups. Slope deposits consist of hemipelagic claystone, debris-flow conglomerate, calciturbidite, and volcaniclastic intervals. syndepositional downslope transport of slope deposits was an important process, as indicated by intervals containing redeposited debris flows, intraformational truncation surfaces, slide blocks, and associated shear planes. Recurrent movement on basin-margin faults and local volcanism probably perpetuated instability of slope deposits. Basinal deposits consist of calcareous claystone with intercalated thin, distal calciturbidite and volcaniclastic beds.

  5. Lithostratigraphic and Isotopic Correlations Between the Xunhua and Linxia Basins, NE Tibet: Implications for Local Climate Variability

    NASA Astrophysics Data System (ADS)

    Hough, B.; Garzione, C.; Wang, Z.; Lease, R.; Yuan, D.; Zhang, P.; Burbank, D.

    2006-12-01

    Changes in local climate conditions associated with the evolution of mountain belts or plateaus are recorded in sediments that accumulate in basins adjacent to the growing feature. The Xunhua and Linxia basins are deep, internally-drained, intermontaine basins located on the NE margin of the Tibetan Plateau that may have been contiguous in the middle Miocene, but were separated at ~8 Ma by the growth of the Laji Shan. New paleomagnetic, sedimentologic, and light stable isotope records indicate that the Xunhua basin record contains an overall coarsening upward trend spanning the past ~8-10 My. The section comprises three distinct facies: ~400 m of calcareous lacustrine mudstones conformably overlain by ~500 m of fluvial sandstones and floodplain mudstones, which coarsen upward to alluvial fan conglomerates. Lithostratigraphic and magnetostratigraphic correlation between the Xunhua basin and previously documented records from the Linxia basin suggest that, prior to growth of the Laji Shan, both basins may have shared a common lacustrine sedimentary history. This interpretation is supported by similar isotopic compositions between Linxia and Xunhua lacustrine carbonates. The lacustrine to fluvial transition in the Xunhua basin is marked by a 1 ‰ increase in δ18O values. A similar enrichment in 18O, however, is not present at the same facies boundary in the Linxia record. We interpret the 1 ‰ increase in δ18O of sedimentary carbonates west of the Laji Shan to suggest that the growing mountain range created a rainshadow on its leeward side, that resulted in aridification west of the Laji Shan.

  6. Magnetostratigraphy of drill-core SG-1b in the western Qaidam Basin (NE Tibetan Plateau) and tectonic implications

    NASA Astrophysics Data System (ADS)

    Zhang, Weilin; Appel, Erwin; Fang, Xiaomin; Song, Chunhui; Setzer, Fabian; Herb, Christian; Yan, Maodu

    2014-04-01

    The Qaidam Basin is an ideal archive to study long-term climate and erosion histories at the NE Tibetan Plateau. We present a magnetostratigraphic study of the 723 m deep drill-core SG-1b of lacustrine sediments at the Jianshan anticline in the western Qaidam Basin. The polarity sequence shows 18 normal and 19 reverse polarity zones which can be readily correlated with chrons C1n-C3Br of the Geomagnetic Polarity Time Scale 2004 (GPTS 2004), dating the core at about 7.3-1.6 Ma. The resulting mean sediment accumulation rate (SAR) between polarity boundaries ranges from 6.5 to 30.4 cm ka-1. High SARs occur within the intervals of >7.3-6.0, 5.2-4.2 and 3.6-2.6 Ma indicating three episodic phases of higher erosion. From the derived variation of SARs and previous results, we conclude that growth strata at the Jianshan anticline started to develop at ˜1.6 Ma by limb rotation. All this we relate to pulse tectonic uplift of the NE Tibetan Plateau and fault-propagation-folding in the Qaidam Basin.

  7. On the tectonics of the Neocomian Rio do Peixe Rift Basin, NE Brazil: Lessons from gravity, magnetics, and radiometric data

    NASA Astrophysics Data System (ADS)

    de Castro, David Lopes; de Oliveira, Diógenes Custódio; Gomes Castelo Branco, Raimundo Mariano

    2007-09-01

    A geophysical perspective based on well-acquired gravity, magnetic, and radiometric data provides good insights into the basin architectural elements and tectonic evolution of the Rio do Peixe Basin (RPB), an Early Cretaceous intracontinental basin in the northeast Brazilian rift system, which developed during the opening of the South Atlantic. NW-SE-trending extensional forces acting over an intensively deformed Precambrian basement yielded a composite basin architecture strongly controlled by preexisting, mechanically weak fault zones in the upper crust. Reactivated NE-SW and E-W ductile shear zones of Brasiliano age (˜0.6 Ga) divided the RPB into three asymmetrical half-grabens (Brejo das Freiras, Sousa, and Pombal subbasins), separated by basement highs of granite bodies that seem to anchor and distinguish the mechanical subsidence of the subbasins. Radiometric and geopotential field data highlight the relationship between the tectonic stress field and the role of a preexisting structural framework inserted in the final rift geometry. The up-to-2000 m thick half-grabens are sequentially located at the inflexion of sigmoidal-shaped shear zones and acquire a typical NE-SW-oriented elliptic shape. The Sousa Subbasin is the single exception. Because of its uncommon E-W elongated form, three-dimensional gravity modeling reveals an E-W axis of depocenters within the Sousa Subbasin framework, in which the eastern shoulders are controlled by NE-SW-trending faults. These faults belong to the Precambrian structural fabric, as is well illustrated by the gamma ray and magnetic signatures of the basement grain. Release faults were identified nearly perpendicular or oblique to master faults, forming marginal strike ramps and horst structures in all subbasins. The emplacement mechanism of Brasiliano granites around the RPB was partially oriented by the same structural framework, as is indicated by the gravity signature of the granitic bodies after removal of the gravity

  8. Sedimentary record of Pleistocene paleodoline evolution in the Ebro basin (NE Spain)

    NASA Astrophysics Data System (ADS)

    Luzón, A.; Pérez, A.; Soriano, M. A.; Pocoví, A.

    2008-03-01

    Pleistocene fluvial deposits of the Ebro River, in NE Spain, are widely affected by faults, fractures and tilting of beds. Based on the lithological, geometrical and textural features of these deposits, seven architectural elements have been differentiated. Gravel Bars (GB), Gravel-filled Channels (CH), Sheets and Channel-fill Sands (SB), are the most common elements and, together with less frequent Overbank Fines (FF), characterize a gravel-dominated braided fluvial system. Gravel Lobes (GL) that draw progressive unconformities and are laterally related to U-shaped or basin-form mud deposits, Sediment Gravity Flow deposits (SG), and Sands with Slumps and Convolute Bedding (SGS), are not typical architectural elements of braided fluvial environments and they are interpreted in this work as related to syn-sedimentary deformation. Our research proves that deformation is due to dissolution of the underlying Tertiary evaporites with genesis of dolines. The development of these karst structures involved both subsidence and sudden collapses that affected previous fluvial sediments. Small depressions (dolines) generated that were progressively filled by syn-sedimentary deformed detrital deposits. A model for the evolution of the doline fills is purposed that envisages several stages: 1) gravitational processes caused remobilisation of previous fluvial gravels that were dragged to the created depression, 2) flooding of the depression and development of a backswamp area that was progressively filled by fine sediments and gravel lobes as a consequence of the overflow of nearby channels, 3) gravel lobes draw progressive unconformities revealing several subsidence episodes related to dissolution, dragging and compaction, 4) non-deformed fluvial facies at the top of the series mark the end of the karstification influence. OSL (Optically Stimulated Luminiscence) ages, the first from the terraces of the Ebro River, demonstrate that karst has developed in this area at least since

  9. The biogeochemical reactivity of suspended particulate matter at nested sites in the Dee basin, NE Scotland.

    PubMed

    Dawson, J J C; Adhikari, Y R; Soulsby, C; Stutter, M I

    2012-09-15

    Variation in the organic matter content associated with suspended particulate matter (SPM) is an often overlooked component of carbon cycling within freshwater riverine systems. The potential biogeochemical reactivity of particulate organic carbon (POC) that affect its interactions and fate, i.e. respired and lost to the atmosphere along river continua or ultimately exported to estuarine and oceanic pools was assessed. Eleven contrasting sites draining nested catchments (5-1837 km(2)) in the River Dee basin, NE Scotland were sampled during summer 2008 to evaluate spatio-temporal variations in quantity and quality (biogeochemical reactivity) of SPM during relatively low flow conditions. Mean SPM concentrations increased from 0.21 to 1.22 mg L(-1) between the uppermost and lowest mainstem sites. Individually, POC concentrations ranged from 0.08 to 0.55 mg L(-1) and accounted for ca. 3-15% of total aqueous organic carbon transported. The POC content was partitioned into autotrophic (2.78-73.0 mg C g(-1) SPM) and detrital (119-388 mg C g(-1) SPM) biomass carbon content. The particulate respired CO(2)-C as a % of the total carbon associated with SPM, measured by MicroResp™ over 18 h, varied in recalcitrance from 0.49% at peat-dominated sites to 3.20% at the lowermost mainstem site. Significant (p<0.05) relationships were observed between SPM biogeochemical reactivity measures (% respired CO(2)-C; chlorophyll α; bioavailable-phosphorus) and arable and improved grassland area, associated with increasing biological productivity downstream. Compositional characteristics and in-stream processing of SPM appear to be related to contributory land use pressures, that influence SPM characteristics and biogeochemistry (C:N:P stoichiometry) of its surrounding aqueous environment. As moorland influences declined, nutrient inputs from arable and improved grasslands increasingly affected the biogeochemical content and reactivity of both dissolved and particulate matter. This

  10. Oceanic crust of the Grenada Basin in the Southern Lesser Antilles Arc Platform

    NASA Astrophysics Data System (ADS)

    Speed, R. C.; Walker, J. A.

    1991-03-01

    Seismic refraction data permit the southern Lesser Antilles arc and surrounding regions to be divided by the velocity of their basement. We propose that high-velocity basement of the arc platform beneath the Grenadine islands and below a part of the Tobago Trough forearc basin is oceanic and continuous and was originally connected with oceanic crust of the Grenada Basin. Low-velocity basements of the Tobago terrane and the arc platform from St. Vincent north lie south and north, respectively, of the high-velocity basement of the arc platform. An oceanic origin of this high-velocity crust in the Grenadines is argued to be more plausible than an origin as unroofed lower arc crust. The segment of probable oceanic crust in the arc platform was greatly uplifted during development of the present island arc, mainly in late Neogene time, relative to the Grenada Basin and Tobago Trough. Accepting the proposition of shallow oceanic crust in the Grenadines, early middle Eocene and possibly older pillow basalts of Mayreau, the oldest rock unit of the southern Lesser Antilles arc platform, may be an exposure of such basement. Major and minor element compositions of Mayreau Basalt are indicative of a spreading rather than arc origin. The stratigraphy of the pillow basalts indicates extrusion in an open marine environment, distant or shielded from sources of arc or continental sediment, followed by a period of pelagic sedimentation above the carbonate compensation depth. The Eocene basalt and pelagic cover formed a relatively deep floor of a marine basin in which arc-derived turbidites and pelagic sediments accumulated over the succeeding 25-30 ma. Such basalts thus indicate a probable spreading origin of the Grenada Basin and an age of cessation of spreading in the region of Mayreau in Eocene time. The configuration of the Eocene basin and the direction of spreading, however, are unknowns. Regional structural relationships imply the spreading was probably backarc, an origin also

  11. Towards quantifying long-term erosion rates in the Campine Basin, NE Belgium

    NASA Astrophysics Data System (ADS)

    Beerten, Koen; Vanacker, Veerle

    2016-04-01

    The Campine Basin, NE Belgium, is situated between the uplifting Ardennes Massif and rapidly subsiding Roer Valley Graben. It contains a thick series of marine, estuarine and continental Neogene and Quaternary sediments, locally more than 300 m. As a result of relief inversion during the Quaternary, the Campine Plateau is nowadays a distinct morphological feature in this basin. Its surface elevation dips from 100 m in the south to 30 m in the north over a distance of about 60 km, which is the result of differential uplift. The Campine Plateau is covered by Early and Middle Pleistocene erosion-resistant fluvial sediments from the Rhine and Meuse and can thus be regarded as a fluvial terrace. The age of deposition and time of abandonment of the terrace have not yet been resolved by direct numerical dating. In this study, we apply the cosmogenic radionuclide (CRN) profiling technique that, in ideal circumstances, allows one to constrain the exposure age, burial age and amount of post-depositional erosion of the landform. Samples were taken from a 3.5 m deep cross-section in coarse river sands that were deposited by the river Rhine, and now situated at an altitude of about 50 m (a.s.l.). Nine of them were prepared for CRN measurements according to state-of-the-art techniques. The in-situ 10Be concentration of the samples was determined using accelerator mass spectrometry (ETH, Zurich). The in-situ 10Be concentrations are 1.5x10e5 atoms/g for the uppermost sample (at 0.3 m depth) and 0.9x10e5 at/g for the lowermost sample (at 3.1 m depth), yielding an estimated 0.6x10e5 at/g of radionuclide accumulation following sediment deposition. Using forward modelling, we solved for the exposure duration and erosion rate that best fit the measured in-situ 10Be depth profile data, nuclide inheritance and their associated analytical uncertainties. Model optimisation is here based on the sum of chi-squared between the measured and modelled 10Be concentrations. When taking previous

  12. Reconstructing the Santa Tecla flash flood in the Ondara River (Ebro Basin, NE Spain)

    NASA Astrophysics Data System (ADS)

    Balasch, J. C.; Tuset, J.; Ramos, M. C.; Martínez-Casasnovas, J. A.

    2009-09-01

    The Santa Tecla flood may be considered the most catastrophic rainfall event in the modern history of Catalonia (NE Iberian Peninsula), and one of the most important in the Western Mediterranean Basin. This event took place during the night between 22nd and 23rd September 1874, in which torrential convective rainfalls generated significant flash floods in most of the small streams in the southern half of Catalonia (i.e. Ondara, Corb, Francolí and Siurana catchments). More than 570 people died, 150 of which in the town of Tàrrega, by the Ondara River. Despite being one of the last huge floods of the pre-instrumental era and, consequently, without any precipitation or flow data, the event was reconstructed both hydraulically and hydrologically for the Ondara River at Tàrrega (150 km2). Thus, the maximum water level and the temporal evolution of the flood were obtained, respectively, from several epigraphic limnimarks found in Tàrrega and from the event description recorded in historical documents. Additionally, the information from local archaeological sites allowed the reconstruction of the fluvial section at Tàrrega at the end of the 19th century. Finally, some old cellars flooded during the event provided information about sediment concentration at the peak flow. The methodology put into practice for the event reconstruction had two stages. The first stage was the hydraulic modelling, which estimated the peak flow. The input data used were the maximum water level given by the limnimetric marks, a digital terrain model of the river bed shape, and the stream and floodplain roughness and channel slope (which were considered similar to the present ones, according to archaeological data). The hydraulic model used was the unidimensional HEC-RAS (USACE), applied in several cross sections of the Ondara River at Tàrrega. The second stage was the hydrological modelling. The objective of this stage was to derive the event hyetograph from the above calculated peak flow

  13. Tectono-eustatic controls on carbonate platform development, Permian basin outcrop-subsurface

    SciTech Connect

    Sarg, J.F.; Romine, K.; Vail, P.R.

    1987-05-01

    Integration of seismic stratigraphic concepts, detailed field studies, and geohistory analysis provides powerful interpretation leverage for deciphering the geologic history of the Permian carbonate platform complexes. The structural history of the Permian basin during the Permian shows two subsidence cycles of 10 to 20 m.y. duration. These subsidence cycles played a major role in the long-term (millions to tens of millions of years) development of the Permian carbonate platforms. During periods of relatively rapid subsidence, aggradation was dominant; during times of slow subsidence, major basinward platform progradation occurred. Superimposed on the long-term tectonic cycles are a series of third-order eustatic cycles (0.5-3 m.y.) which controlled development of 23 depositional sequences. Each sequence is composed of three depositional systems tracts: (1) a lower basin-restricted wedge interpreted to have been deposited during a relative fall and lowstand of sea level; (2) a transgressive systems tract of variable thickness; and (3) an upper aggradational to progradational carbonate platform system interpreted to have been deposited during a relative highstand in sea level. The lowstand systems tracts are composed dominantly of quartz sandstone, commonly intercalated with carbonate debris beds at the toe-of-slope. Two highstand depositional styles are differentiated here: (1) a keep-up system which maintains pace with periodic rises in relative sea level and displays a mounded-oblique stratal geometry at the platform margin and (2) a catch-up system which represents a relatively slow rate of accumulation and displays a sigmoid profile at the platform margin. Sequence boundaries display erosional truncation (subaerial on shelf or at shelf edge; subaqueous on slope) and/or subaerial exposure.

  14. Post-rift geodynamics of the Songliao Basin, NE China: Origin and significance of T11 (Coniacian) unconformity

    NASA Astrophysics Data System (ADS)

    Song, Ying; Ren, Jianye; Stepashko, Andrei A.; Li, Jianguo

    2014-11-01

    The T11 unconformity lies between the Qingshankou and Yaojia Formations in the post-rifting sequence of the Cretaceous Songliao Basin, NE China. It is intimately associated with petroleum reservoirs and considered to be a disconformity forming in the tectonic quiet stage. We present the interpretations from new seismic surveys and cored sections of the Cretaceous Continental Scientific Drilling borehole (CCSD-SK-1) in order to resolve the nature and origin of T11 unconformity. The T11 is often a low-angle unconformity with underlying Qingshankou Formation having been deformed and eroded prior to deposition of the Yaojia Formation. In the post-rift evolution of the basin it marks an abrupt change from a deep lake to shallow lake or subaerial environment, documented by reddening of the lacustrine mudstone, extinction of the ostracod assemblages and a great increase of coarse detrital inputs. The sharp change of depositional environment, the truncation of gentle folds and the cluster of volcanic and paleoearthquake activities, all happened simultaneously, immediately before the development of T11 unconformity, indicating a significant regional compressional uplift event in the basin. The timing of the T11 unconformity formation is within the interval 88-86.2 Ma. Correlations with coeval unconformities in other Cretaceous sedimentary basins in eastern Asia indicate that this compressional uplift coincided with an episode of global plate reorganization between the Eurasian and Paleo-Pacific plates that culminated at 88-87 Ma. During this short interval the northeast Asian margin, in eastern China, South Korea, Japan and Russian Far East experienced widespread violent volcanic and granite emplacement activity triggered by compression resulting from rapid and orthogonal slab subduction. The post-rift basin tectonic inversion occurred during T11 (Coniacian) time; thereafter the basin again evolved in an extension regime. Two subsidence phases in post-rift history took

  15. ESR dating of Neogene marine sands from the southern North Sea basin, NE Belgium: first results

    NASA Astrophysics Data System (ADS)

    Iacovo, Serena; Jivanescu, Mihaela; Beerten, Koen; Stesmans, Andre; Vandenberghe, Noël

    2013-04-01

    Quantifying Neogene and Quaternary geodynamic processes requires reliable age control on the geological record from which the rate and intensity of these processes are usually derived. The nature and geometry of marine sediments preserved in the southern North Sea basin, NE Belgium, are influenced by geodynamic processes such as tectonic movements and eustatic sea level changes. Yet, the geochronology of these sediments is almost entirely based on micropalaeontological analyses and subsequent correlations with widely accepted geological boundaries. In recent years, the electron spin resonance (ESR) dating method has been applied to buried sediments that range in age between ~ 100 ka and several Ma. The method is based on the measurement of accumulated radiation damage in quartz crystals during burial, and can thus in theory be applied to obtain absolute numerical age control on any quartz-rich sediment given several conditions are met. The most important of these is sunlight bleaching of pre-existing radiation damage prior to burial. In this case study, we present preliminary ESR dating results of three samples from a cored borehole in Miocene glauconite-rich sands, which are biostratigraphically estimated as between 7 Ma and 11 Ma (Tortonian). Following chemical and physical purification of the samples (taken at 107 m, 135 m and 147 m depth), quartz grains (100-200 µm) were irradiated by Co-60 gamma rays to doses between 1-150 kGy. Individual aliquots (each weighting several 100 mg) were measured at cryogenic temperatures in a JEOL X-band ESR spectrometer operating at a microwave frequency of ~ 9.2 GHz. Defect densities were derived by integration of relevant ESR spectra, and making use of a comounted defect density calibrated marker sample. Subsequently, the equivalent dose was calculated using the thus constructed dose curves (including the natural, unirradiated, aliquot). Finally, dose rates were determined using high resolution gamma ray spectrometry in the

  16. An Early to Middle Miocene Magnetostratigraphy From the Ebro Basin (NE Spain)

    NASA Astrophysics Data System (ADS)

    Garces, M.; Perez-Rivares, F. J.; Larrasoana, J. C.; Murelaga, X.; Arenas, C.; Pardo, G.; Cabrera, L.

    2007-05-01

    The Ebro Basin represents the last stage of evolution of the south-pyrenean foreland, which formed since the late Cretaceous as a result of northwards subduction and collision between the Iberian and the European plates. The basin evolved into a land-locked configuration by the latest Eocene when continued compression led to closing of its NW marine gateway. Filling of the basin continued from late Eocene to the late Middle Miocene, leading to the accumulation of a thick sequence of alluvial and lacustrine sediments. In the middle-to-late Miocene the basin opened towards the Mediterranean and river incision cut through the complete Eocene to Miocene sedimentary succession. Nearly undeformed Early to Middle Miocene units crop out extensively in the central parts of the basin and have delivered a long and continuous magnetostratigraphic record. Considering the time resolution achievable with magnetostratigraphy, the numerous studies on the sedimentary sequences of the Ebro Basin provide compelling evidence for stratigraphic completeness and relatively steady sedimentation over the Oligocene-Miocene time interval. The perfect match with the geomagnetic polarity time scale provides a robust and high resolution chronology for the late stages of basin infill, allowing cyclostratigraphic analysis to be made as well as correlation with the various records of regional to global climate change. Noticeably, the Early- Middle Miocene boundary corresponds in the central Ebro Basin with a remarkable and sharp transition from a marly-gypsiferous to a carbonate unit. It represents a significant environmental change from a dry period dominated by a hipersaline water body to a wetter period with rapid installation of an areally extensive carbonate lake. Magnetostratigraphic data indicates that this period of lacustrine expansion is simultaneously recorded in other basins of the Iberian Plate and corresponds to the climatic optimum of the Langhian stage that preceeded the middle

  17. Magnetostratigraphy of deep drilling core SG-1 in the western Qaidam Basin (NE Tibetan Plateau) and its tectonic implications

    NASA Astrophysics Data System (ADS)

    Zhang, Weilin; Appel, Erwin; Fang, Xiaomin; Song, Chunhui; Cirpka, Olaf

    2012-07-01

    The Qaidam Basin is the largest intermontane basin of the northeastern Tibetan Plateau and contains a continuous Cenozoic sequence of lacustrine sediments. A ~ 1000-m-deep drilling (SG-1) with an average core recovery of ~ 95% was carried out in the depocenter of the Chahansilatu playa (sub-depression) in the western Qaidam Basin, aimed to obtain a high-resolution record of the paleoenvironmental evolution and the erosion history. Stepwise alternating field and thermal demagnetization, together with rock magnetic results, revealed a stable remanent magnetization for most samples, carried by magnetite. The polarity sequence consisted of 16 normal and 15 reverse zones which can be correlated with chrons 1n to 2An of the global geomagnetic polarity time scale. Magnetostratigraphic results date the entire core SG-1 at ~ 2.77 Ma to ~ 0.1 Ma and yielded sediment accumulation rate (SAR) ranging from 26.1 cm/ka to 51.5 cm/ka. Maximum SARs occurred within the intervals of ~ 2.6-2.2 Ma and after ~ 0.8 Ma, indicating two episodes of erosion, which we relate to pulse tectonic uplift of the NE Tibetan Plateau with subsequent global cooling.

  18. Overview of the structural geology and tectonics of the Central Basin Platform, Delaware Basin, and Midland Basin, West Texas and New Mexico

    SciTech Connect

    Hoak, T.; Sundberg, K.; Ortoleva, P.

    1998-12-31

    The structural geology and tectonics of the Permian Basin were investigated using an integrated approach incorporating satellite imagery, aeromagnetics, gravity, seismic, regional subsurface mapping and published literature. The two primary emphases were on: (1) delineating the temporal and spatial evolution of the regional stress state; and (2) calculating the amount of regional shortening or contraction. Secondary objectives included delineation of basement and shallower fault zones, identification of structural style, characterization of fractured zones, analysis of surficial linear features on satellite imagery and their correlation to deeper structures. Gandu Unit, also known as Andector Field at the Ellenburger level and Goldsmith Field at Permian and younger reservoir horizons, is the primary area of interest and lies in the northern part of Ector county. The field trends northwest across the county line into Andrews County. The field(s) are located along an Ellenburger thrust anticline trap on the eastern margin of the Central Basin Platform.

  19. Magma Emplacement and the 3D Geometry of Igneous Bodies in Rift Basins: Insights from the Bornu Basin, Onshore NE Nigeria

    NASA Astrophysics Data System (ADS)

    Suleiman, Adamu; Jackson, Christopher; Magee, Craig; Fraser, Alastair

    2016-04-01

    Recent studies of regional unconformities in the circum-South Atlantic tectonic plates have linked unconformity age to the timing of changes in the azimuth of oceanic fracture zones, caused by plate interactions during opening of the South Atlantic. This observation is significant, proposing that a plate boundary geodynamic processes are transmitted into and expressed in plate interiors. However, it is not yet clear if and how other geologic events, such as intra-plate magmatism, may be linked to changes in the oceanic fracture azimuthal geometry. Here we use 2D and 3D seismic reflection, geochemical, borehole datasets and outcrop observations from the Bornu Basin, one of several intra-continental rift basins located in NE Nigeria to constrain the 3D geometry of igneous bodies and magmatic emplacement processes. This allows us to link South Atlantic plate boundary geodynamics and magmatism in the surrounding continental rift basins. Seismic attributes, reflection intensity, relative acoustic impedance, were used to identify and map igneous intrusions. Saucer-shaped sills are the most common type of intrusion, although en-echelon sills, up to 1.4 km in length, were also identified. The 3D geometry of the sills reveals the detailed structural components like inner sill, inclined sheets and outer sill. A mapped bifurcating network of the sills suggests magma emplacement process through upward and outward propagation. Seismic-stratigraphic observations indicate that igneous activity occurred in the Early Cretaceous, Late Cretaceous and Paleogene corresponding to the timing of major azimuth changes observed in the Kane Oceanic fracture zone in the South Atlantic Ocean. Overall, our study, suggests a possible influence of plate boundary geodynamics on intra-plate magmatism as reflected in the link between the time of changes in the azimuth of oceanic fracture zones and magmatic emplacement observed in the tectono-stratigraphy of the intra-continental rift basins.

  20. Magma Emplacement and the 3D Geometry of Igneous Bodies in Rift Basins: Insights from the Bornu Basin, Onshore NE Nigeria

    NASA Astrophysics Data System (ADS)

    Suleiman, A. A.; Jackson, C. A. L.; Magee, C.; Fraser, A.

    2015-12-01

    Recent studies of regional unconformities in the circum-South Atlantic tectonic plates have linked unconformity age to the timing of changes in the azimuth of oceanic fracture zones, caused by plate interactions during opening of the South Atlantic. This observation is significant, proposing that a plate boundary geodynamic processes are transmitted into and expressed in plate interiors. However, it is not yet clear if and how other geologic events, such as intra-plate magmatism, may be linked to changes in the oceanic fracture azimuthal geometry. Here we use 2D and 3D seismic reflection, geochemical, borehole datasets and outcrop observations from the Bornu Basin, one of several intra-continental rift basins located in NE Nigeria to constrain the 3D geometry of igneous bodies and magmatic emplacement processes. This allows us to link South Atlantic plate boundary geodynamics and magmatism in the surrounding continental rift basins. Seismic attributes, reflection intensity, relative acoustic impedance, were used to identify and map igneous intrusions. Saucer-shaped sills are the most common type of intrusion, although en-echelon sills, up to 1.4 km in length, were also identified. The 3D geometry of the sills reveals the detailed structural components like inner sill, inclined sheets and outer sill (Fig.1). A mapped bifurcating network of the sills suggests magma emplacement process through upward and outward propagation. Seismic-stratigraphic observations indicate that igneous activity occurred in the Early Cretaceous, Late Cretaceous and Paleogene corresponding to the timing of major azimuth changes observed in the Kane Oceanic fracture zone in the South Atlantic Ocean. Overall, our study, suggests a possible influence of plate boundary geodynamics on intra-plate magmatism as reflected in the link between the time of changes in the azimuth of oceanic fracture zones and magmatic emplacement observed in the tectono-stratigraphy of the intra-continental rift basins.

  1. [Book review] Ecology, biogeography and management of Pinus halepensis and P. brutia forest ecosystems in the Mediterranean Basin, by G. Ne'eman and L. Trabaud

    USGS Publications Warehouse

    Keeley, J.E.

    2001-01-01

    Review of: Ne'eman, G. & Trabaud, L. Ecology, Biogeography and Management of Pinus halepensis and P. brutia Forest Ecosystems in the Mediterranean Basin. xii + 412 pp. Backhuys Publishers, Leiden. ISBN 90?5782-055-2 (hardcover). Price: USD 120.00.

  2. Age constraints on late Mesozoic lithospheric extension and origin of bimodal volcanic rocks from the Hailar basin, NE China

    NASA Astrophysics Data System (ADS)

    Li, Shuang-Qing; Hegner, Ernst; Yang, Yi-Zeng; Wu, Jia-De; Chen, Fukun

    2014-03-01

    Following the amalgamation of the late Mesoproterozoic-Carboniferous Central Asian Orogenic Belt with the Siberian and North China cratons, NE China underwent late Mesozoic lithospheric extension and widespread formation of volcano-sedimentary basins. We report U-Pb zircon ages and geochemical data for mafic and felsic volcanic rocks from the Hailar basin, located about 1000 km north of Beijing. Zircon populations of six felsic rock samples analyzed by laser ablation ICP-MS yielded similar U-Pb age spectra ranging from 158 to 125 Ma. The youngest zircon ages are interpreted as time of magma eruption and the xenocrystic zircon-age spectra as evidence for a protracted melting of lower crust due to the underplating of mantle-derived magmas during lithospheric extension. The volcanic assemblage has a bimodal composition comprising geochemically evolved trachybasalts and felsic volcanic rocks of I- and subordinate A-type compositions. The mafic volcanic rocks have negative Nb-anomalies, high Th/Nb and Ce/Pb ratios, low initial ɛNd values of + 0.4 to + 3.4, and radiogenic Pb and Sr isotopes all interpreted as evidence for the melting of passively upwelling asthenosphere and lithospheric mantle previously modified by plate subduction. The xenocrystic zircon ages and chemical/isotopic data of the felsic rocks support an origin from juvenile crustal protoliths: the data of I-type felsic rocks are consistent with the melting of underplated mafic protoliths and those of the A-type rhyolites support the melting of a crustal source with a composition similar to the I-type felsites with apatite controlling their Nb anomaly. The evidence for the persistent melting of a subduction-modified mantle in NE China is in agreement with a model of an extending coupled upper mantle-crust system due to a retreating Paleo-Pacific trench.

  3. Intra-platform tectono-sedimentary response to geodynamic transition along the margin of the Tarim Basin, NW China

    NASA Astrophysics Data System (ADS)

    Gao, Zhiqian; Fan, Tailiang

    2014-12-01

    The Tarim Basin has experienced three tectonic evolutionary phases from the Cambrian to Ordovician: (1) Regional extension from the late Neoproterozoic to Mid-Early Cambrian, (2) Relatively weak regional compression from the Late Cambrian to Mid-Early Ordovician, and (3) Regional compression during the Late Ordovician. Intra-platform tectonic and sedimentary characteristics indicate a clear linkage to the tectonic evolution of the basin margin during early Paleozoic time. During the Cambrian, small intra-platform rift-related depressions formed during an extensional setting. During the Mid-Early Ordovician, a transition from extension to compression caused formation of the Tazhong and Tabei paleo-uplifts and major unconformities T74 (base of the Late Ordovician). The evolving paleo-geomorphology led to differentiation of sedimentary facies, and numerous intra-platform shoals formed during deposition of the Early Ordovician Yingshan Formation. During the Late Ordovician, regional compression began, which changed the platform margin slopes into four slopes that surrounded the three isolated island uplifts of Tabei, Tazhong, and Tangnan in the Late Ordovician. Simultaneously, the basin margin dynamic conditions also changed the relative sea level and filling pattern of the basin. In the Early and Middle Cambrian, the Tarim Basin mainly developed a progradational ramp-type platform due to relative sea level fall. From the Late Cambrian to Early Ordovician the relative sea level began to rise, resulting in an aggradational-retrograding rimmed margins-type platform. In the Late Ordovician, along with a further rise in relative sea level, the basin mainly developed isolated platform.

  4. Geochemical and palynological records for the end-Triassic Mass-Extinction Event in the NE Paris Basin (Luxemburg)

    NASA Astrophysics Data System (ADS)

    Kuhlmann, Natascha; van de Schootbrugge, Bas; Thein, Jean; Fiebig, Jens; Franz, Sven-Oliver; Hanzo, Micheline; Colbach, Robert; Faber, Alain

    2016-04-01

    The End-Triassic mass-extinction event is one of the "big five" mass extinctions in Earth's history. Large scale flood basalt volcanism associated with the break-up of Pangaea, which resulted in the opening of the central Atlantic Ocean, is considered as the leading cause. In addition, an asteroid impact in Rochechouart (France; 201 ± 2 Ma) may have had a local influence on ecosystems and sedimentary settings. The Luxembourg Embayment, in the NE Paris Basin, offers a rare chance to study both effects in a range of settings from deltaic to lagoonal. A multidisciplinary study (sedimentology, geochemistry, palynology) has been carried out on a number of outcrops and cores that span from the Norian to lower Hettangian. Combined geochemical and palynological records from the Boust core drilled in the NE Paris Basin, provide evidence for paleoenvironmental changes associated with the end-Triassic mass-extinction event. The Triassic-Jurassic stratigraphy of the Boust core is well constrained by palynomorphs showing the disappaerance of typical Triassic pollen taxa (e.g. Ricciisporites tuberculates) and the occurrence of the marker species Polypodiisporites polymicroforatus within the uppermost Rhaetian, prior to the Hettangian dominance of Classopollis pollen. The organic carbon stable isotope record (δ13Corg) spanning the Norian to Hettangian, shows a series of prominent negative excursions within the middle Rhaetian, followed by a trend towards more positive values (approx -24 per mille) within the uppermost Rhaetian Argiles de Levallois Member. The lowermost Hettangian is characterized by a major negative excursion, reaching - 30 per mille that occurs in organic-rich sediments. This so-called "main negative excursion" is well-known from other locations, for example from Mariental in Northern Germany and from St Audrie's Bay in England, and Stenlille in Denmark. Based on redox-sensitive trace element records (V, Cr, Ni, Co, Th, U) the lowermost Hettangian in most of

  5. Understanding the Mesozoic kinematic evolution in the Cameros basin (Iberian Range, NE Spain) from magnetic subfabrics and mesostructures

    NASA Astrophysics Data System (ADS)

    García-Lasanta, Cristina; Oliva-Urcia, Belén; Román-Berdiel, Teresa; Casas, Antonio M.; Hirt, Ann M.

    2014-09-01

    Analysis of anisotropy of magnetic susceptibility (AMS) and brittle mesostructures (hydroplastic synsedimentary faults and tension gashes) is applied in this study in order to characterize the Mesozoic tectonic events in the Cameros basin (NW Iberian Range), formed between Tithonian and Albian times. Low-field AMS at room and low temperature (LF-AMS at RT and LF-AMS at LT, respectively) together with high-field AMS (HF-AMS) measurements allow separating ferro- and paramagnetic fabrics. The combination of LF-AMS at LT and HF-AMS torque measurements confirms the reliability of both procedures in terms of isolating the paramagnetic contribution to the AMS. Magnetic fabric results combined with the analyses of synsedimentary faults indicate a NW-SE extension direction during Aptian (and probably Barremian) times. This extension direction is perpendicular to the main extension direction (NE-SW) prevailing during early and late stages of basin evolution. It is also consistent with extension direction deduced from large-scale bending folds and tension gashes, developed after partial lithification. Cleavage development during Albian enhanced the orientation of the magnetic fabric in lithologies where the previous extensional magnetic lineation is coaxial with the expected one for compression.

  6. Palaeoenvironmental and chronological constraints on the Early Pleistocene mammal fauna from loess deposits in the Linxia Basin, NE Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Zan, Jinbo; Fang, Xiaomin; Zhang, Weilin; Yan, Maodu; Zhang, Tao

    2016-09-01

    The Longdan mammal fauna from the central part of Linxia Basin, NE Tibetan Plateau, is the first Early Pleistocene fauna in China in which the fossils are derived loess deposits, and it provides an excellent opportunity to document mammalian and environmental evolution in Asia. However, the precise age and palaeoenvironmental setting of the fauna are controversial due to the poor exposure of the outcrop section. In the present study, a 105-m-long drill core was obtained from Longdan village and used for detailed magnetostratigraphic dating. The results demonstrate that the late Pliocene- Pleistocene loess deposits in the Longdan section deposited since ca. 3 Ma and that the Longdan fauna has an age range of 2.5-2.2 Ma. In addition, the results of lithological and rock magnetic analyses demonstrate that paleosols are weakly developed throughout the whole core and that in the lower and middle parts the core the magnetic susceptibility and its frequency dependence are relatively low and uniform. These observations, combined with the ecological characteristics of the Longdan fauna, indicate that during the Early Pleistocene the climate in the Longdan area, and even in the Linxia Basin, was sub-humid and that the aeolian dust was frequently subjected to post-depositional reworking by water.

  7. Subduction, platform subsidence, and foreland thrust loading: The late Tertiary development of Taranaki Basin, New Zealand

    NASA Astrophysics Data System (ADS)

    Holt, W. E.; Stern, T. A.

    1994-10-01

    Borehole, seismic, and gravity data are used to investigate deformation of continental lithosphere at a Miocene collisional zone. Deformation is manifested in the three following principal forms: a long wavelength (>500 km) platform subsidence ascribed to mantle convection; flexural deformation on a scale of 100-200 km due to crustal thrusting at the eastern boundary of the Taranaki Basin; and a ductile thickening, evident on the deep seismic section of Taranaki Basin, that occurs on a scale of ˜10 km. Evidence for flexural deformation principally comes from the deep seismic section that shows a 150-km wavelength bending of the Moho down toward the major zone of thrusting within the Taranaki Fault Zone. Paleowater depths, however, provide evidence for an initial early Miocene regional subsidence that is too long in wavelength to be explained by flexure induced from thrust sheet loading. Instead, we propose that this broad "platform subsidence" was driven by loading from a deep source, probably subduction-induced flow in the mantle. By ˜22-19 Ma, 1-2 km of water existed over most of the area now occupied by South Taranaki Basin. By ˜19-17 Ma the water depth in the zone east of the Taranaki Basin, the Taranaki Fault Zone, had been replaced by rock due to submarine thrusting and crustal thickening. This build up of submarine topography in the Taranaki Fault Zone constitutes part of the load (25±8 MPa) that created and maintains South Taranaki Basin. Gravity data place further constraints on loading at the thrust front and point to an additional intracrustal loading, equivalent to 15±7 MPa over a 50-km-wide zone. This intracrustal load is explained as being due to thick-skinned thrusting bringing denser, lower-crustal rocks nearer to the surface in the thrust zone. The complete load on the Taranaki foreland is therefore in three parts; the submarine-topographic load, the intracrustal load, and the loading of infilling sediments.

  8. Variations of fluvial tufa sub-environments in a tectonically active basin, Pleistocene Teruel Basin, NE Spain

    NASA Astrophysics Data System (ADS)

    Camuera, Jon; Alonso-Zarza, Ana M.; Rodríguez-Berriguete, Álvaro; Meléndez, Alfonso

    2015-12-01

    The Pleistocene Tortajada fluvial deposit occurs in the eastern active margin of the Teruel Basin. It developed in the early stages of opening of the basin and at present is disconnected to the Alfambra River. The preserved deposits show that the fluvial system consisted in three different sub-environments including: Upper Terraces, Ponds and Cascades. The main facies are framestones of stems, phytoclastic rudstone, framestone of bryophytes, peloidal and filamentous stromatolites, mudstone and detrital (conglomerates and slope-breccias) facies. These facies are arranged in three different sequence types, all of them showing a lower detrital term followed by pond and, in cases, cascade deposits. The microfacies analyses reveal that both biotic and abiotic processes performed an important role in the deposition within the river. Isotopic analyses (δ18O from - 8.58‰ to - 6.70‰ VPDB and δ13C from - 7.44‰ to - 3.97‰ VPDB) are indicative of meteoric water within a hydrologically open system. The carbonate hinterland rocks, together with a semi-arid to sub-humid climate favored carbonate accumulation within the river. Our results point out that the location, morphology and sedimentary sequences of the Tortajada fluvial system had an important tectonic control. The situation of the main and secondary faults controlled the paleomorphology of the river floor. Thus cascades are found in areas of important step faults, whereas the spaces between faults were occupied by fluviatile/lacustrine areas. In addition the development of the different sedimentary sequences was also a reflection of movements of these faults. In short, our study may confirm that tectonism is an important control on tufa development.

  9. Oscillation of mineral compositions in Core SG-1b, western Qaidam Basin, NE Tibetan Plateau.

    PubMed

    Fang, Xiaomin; Li, Minghui; Wang, Zhengrong; Wang, Jiuyi; Li, Jiao; Liu, Xiaoming; Zan, Jinbo

    2016-01-01

    Uplift of the Tibetan Plateau since the Late Miocene has greatly affected the nature of sediments deposited in the Qaidam Basin. However, due to the scarcity of continuously dated sediment records, we know little about how minerals responded to this uplift. In order to understand this response, we here present results from the high-resolution mineral profile from a borehole (7.3-1.6 Ma) in the Basin, which shows systematic oscillations of various evaporite and clay minerals that can be linked to the variation of regional climate and tectonic history. In particular, x-ray diffraction (XRD) analyses show that carbonate minerals consist mainly of calcite and aragonite, with minor ankerite and dolomite. Evaporates consist of gypsum, celesite and halite. Clay minerals are principally Fe-Mg illite, mixed layers of illite/smectite and chlorite, with minor kaolinite and smectite. Following implications can be drawn from the oscillations of these minerals phases: (a) the paleolake was brackish with high salinity after 7.3 Ma, while an abrupt change in the chemical composition of paleolake water (e.g. Mg/Ca ratio, SO4(2-) concentration, salinity) occurred at 3.3 Ma; (b) the three changes at ~6.0 Ma, 4.5-4.1 Ma and 3.3 Ma were in response to rapid erosions/uplift of the basin; PMID:27625177

  10. Detrital zircon U-Pb geochronology and stratigraphy of the Cretaceous Sanjiang Basin in NE China: Provenance record of an abrupt tectonic switch in the mode and nature of the NE Asian continental margin evolution

    NASA Astrophysics Data System (ADS)

    Zhang, Feng-Qi; Chen, Han-Lin; Batt, Geoffrey E.; Dilek, Yildirim; A, Min-Na; Sun, Ming-Dao; Yang, Shu-Feng; Meng, Qi-An; Zhao, Xue-Qin

    2015-12-01

    The age spectra obtained from 505 spots of detrital zircon U-Pb ages of five representative sandstone samples from the Sanjiang Basin in NE China point to a significant change in its provenance during the Coniacian-Santonian. The predominant detrital source for the Sanjiang Basin during the early Cretaceous was the Zhangguangcai Range magmatic belt and Jiamusi Block along its western and southern periphery, whereas it changed in the late Cretaceous to its eastern periphery. The timing of these inferred changes in the detrital source regions and drainage patterns nearly coincide with the age of a regional unconformity in and across the basin. The time interval of non-deposition and unconformity development was coeval with a transitional period between an extensional tectonic regime in the early Cretaceous and a contractional deformation episode in the late Cretaceous. The Sanjiang Basin evolved during this time window from a backarc to a foreland basin. The migration of the coastal orogenic belt and the fold and thrust belt development farther inland during the late Cretaceous marked the onset of regional-scale shortening and surface uplift in the upper plate of a flat (or very shallow-dipping) subduction zone. The stratigraphic record, the detrital source and geochronology of the basinal strata, and the internal structure of the Sanjiang Basin present, therefore, an important record of a tectonic switch in the nature of continental margin evolution of Northeast Asia during the late Mesozoic.

  11. Structural subprovinces of the Central Basin Platform, west Texas: Strike-slip bounded crustal blocks

    SciTech Connect

    Gardiner, W.B. )

    1990-05-01

    The Central Basin platform (CBP) of west Texas is composed of six structural blocks, which moved independently during the Ouachita orogeny. As the South American plate collided with North America the Wasson uplift on the northwestern shelf of the Permian basin acted as a buttress against which the CBP was compressed. Shear forces transmitted through the crust resulted in buckling, uplifting, and faulting of the greater CBP. Although the platform is dominated by vertical movement, it did not however, uplift as a single tectonic unit. Rather, it splintered into six megablocks, which moved simultaneously along oblique-slip fault systems. A tectonic model for formation of the CBP is useful for predicting the orientation and spacing of fault systems. The three structurally highest blocks on the CBP, the Eunice high, the Sand Hills high, and the Fort Stockton uplift, show three distinct positive gravity and magnetic anomalies. These county-sized blocks (35 x 80 km) share similar characteristics: (1) they are bounded by strike-slip faults that involve basement uplift; (2) they have maximum structural deformation along their margins where bends in the strike-slip fault system enhance compressions; and (3) their oil is trapped in high-angle fault structures (R-shears ) along the clock boundaries, but toward the center of the blocks, oil tends to accumulate at unconformity and fold traps. Strike-slip fault systems in west Texas are subtle, with only about 3-7 km of offset and commonly may be overlooked. However, detailed regional mapping indicates that these individual fault segments are parts of through-going systems, which are distributed in logical patterns based upon models for strike-slip tectonics.

  12. Sedimentary characteristics of carbonate intra-platform shoals and their formation in Ordovician Tarim Basin, West China

    NASA Astrophysics Data System (ADS)

    Meng, M.

    2015-12-01

    The widely distributed carbonate intra-platform shoals has become a new important exploration target within the Tarim Basin, where reservoirs of Yubei oil-field (discovered in 2011) and the Shunnan oil-field (discovered in 2013) occur. Better understanding of the sedimentary characteristics and formation of intra-platform shoals is significant for predicting the distribution of Ordovician shoal reservoirs. The sedimentary characteristics, distribution patterns and formation mechanisms of carbonate intra-platform shoals in Ordovician Tarim Basin were studied based on outcrop analogue, core data, thin section observation, seismic, and well log data. Those shoals include oolitic shoal, intraclast shoal and bioclastic shoal. The intra-platform shoal consists of three sedimentary units: shoal base, shoal core and shoal cover, which are adjacent to intershoal sea faces. Laterally, the intra-platform shoals occurred as a more continuous sheet-like body.The intra-platform shoals deposited mainly in the lowstand systems tract and late stage of highstand systems tract. Several factors were probably responsible for the occurrence of intra-platform shoals, including: (i) a relatively shallow-water condition with a strong hydrodynamic environment, (ii) high-frequency oscillations of the sea level, and (iii) Subtle paleo-highs and relatively weak structural activities, which are important for the spatial distribution of reservoir facies.

  13. Integrated Assessment of Heavy Metal Contamination in Sediments from a Coastal Industrial Basin, NE China

    PubMed Central

    Li, Xiaoyu; Liu, Lijuan; Wang, Yugang; Luo, Geping; Chen, Xi; Yang, Xiaoliang; Gao, Bin; He, Xingyuan

    2012-01-01

    The purpose of this study is to investigate the current status of metal pollution of the sediments from urban-stream, estuary and Jinzhou Bay of the coastal industrial city, NE China. Forty surface sediment samples from river, estuary and bay and one sediment core from Jinzhou bay were collected and analyzed for heavy metal concentrations of Cu, Zn, Pb, Cd, Ni and Mn. The data reveals that there was a remarkable change in the contents of heavy metals among the sampling sediments, and all the mean values of heavy metal concentration were higher than the national guideline values of marine sediment quality of China (GB 18668-2002). This is one of the most polluted of the world’s impacted coastal systems. Both the correlation analyses and geostatistical analyses showed that Cu, Zn, Pb and Cd have a very similar spatial pattern and come from the industrial activities, and the concentration of Mn mainly caused by natural factors. The estuary is the most polluted area with extremely high potential ecological risk; however the contamination decreased with distance seaward of the river estuary. This study clearly highlights the urgent need to make great efforts to control the industrial emission and the exceptionally severe heavy metal pollution in the coastal area, and the immediate measures should be carried out to minimize the rate of contamination, and extent of future pollution problems. PMID:22768107

  14. Tectonic and climate control of oil shale deposition in the Upper Cretaceous Qingshankou Formation (Songliao Basin, NE China)

    NASA Astrophysics Data System (ADS)

    Jia, Jianliang; Liu, Zhaojun; Bechtel, Achim; Strobl, Susanne A. I.; Sun, Pingchang

    2013-09-01

    Oil shales were deposited in the Songliao Basin (NE China) during the Upper Cretaceous period, representing excellent hydrocarbon source rocks. High organic matter (OM) contents, a predominance of type-I kerogen, and a low maturity of OM in the oil shales are indicated by bulk geochemical parameters and biomarker data. A major contribution of aquatic organisms and minor inputs from terrigenous land plants to OM input are indicated by n-alkane distribution patterns, composition of steroids, and organic macerals. Strongly reducing bottom water conditions during the deposition of the oil shale sequences are indicated by low pristane/phytane ratios, high C14-aryl-isoprenoid contents, homohopane distribution patterns, and high V/Ni ratios. Enhanced salinity stratification with mesosaline and alkaline bottom waters during deposition of the oil shales are indicated by high gammacerane index values, low MTTC ratios, high β-carotene contents, low TOC/S ratios, and high Sr/Ba ratios. The stratified water column with anoxic conditions in the bottom water enhanced preservation of OM. Moderate input of detrital minerals during the deposition of the oil shale sequences is reflected by titanium concentrations. In this study, environmental conditions in the paleo-lake leading to OM accumulation in the sediments are related to sequence stratigraphy governed by climate and tectonics. The first Member of the Qingshankou Formation (K2qn1) in the Songliao Basin, containing the oil shale sequence, encompasses a third-order sequence that can be divided into three system tracts (transgressive system tract—TST, highstand system tract—HST, and regressive system tract—RST). Enrichment of OM changed from low values during TST-I to high-moderate values during TST-II/III and HST-I/II. Low OM enrichment occurs during RST-I and RST-II. Therefore, the highest enrichment of OM in the sediments is related to stages of mid-late TST and early HST.

  15. Late-Miocene palaeoecological evolution of the Tianshui Basin, NE Tibetan Plateau: Evidence from stable organic carbon isotope record

    NASA Astrophysics Data System (ADS)

    Hou, Zhanfang; Li, Jijun; Song, Chunhui; Meng, Jingjing; Zhang, Jun

    2015-02-01

    The spatial and temporal variations and the driving mechanisms of C3/C4 vegetation evolution throughout the Miocene have been a matter of long-standing debate. A continuous lacustrine-fluvial sediment sequence widely exposed in the Tianshui Basin, NE Tibetan Plateau provides great potential for deciphering the C3/C4 vegetation dynamics during the Miocene. Based on the measurements of δ13Corg, C, N, and C/N ratios of organic matter of this sediment sequence, here we present a new perspective on vegetation history in inland Asia during the period from 17.1 to 6.1 Ma. The organic matter preserved in the Tianshui Basin is most likely a mixture of terrestrial and aquatic origins. The lack of correlation between organic δ13Corg and carbonate δ13Ccarb indicates that terrestrial plants made a dominant contribution to the organic matter. The δ13Corg of organic matter shows negative values (between -24.1‰ and -28.3‰) along the sequence from 17.1 to 6.1 Ma, indicating a predominance of C3 plants. More specifically, our results indicate that the δ13Corg values of organic matter show a significant increase by ca. 1.4‰ from -26.6‰ to -25.2‰ from 7.1 Ma onwards (equivalent to ca. 10% increase in C4 plants), reflecting the initial occurrence of C4 plants. The occurrence and expansion of the C4 component in the study area is supposed to be a result of increasing summer precipitation due to the enhanced Asian Summer Monsoon since that time.

  16. Turbulence observations over a desert basin using a kite/tethered-blimp platform

    NASA Astrophysics Data System (ADS)

    Eaton, Frank D.; Balsley, Ben B.; Frehlich, Rod G.; Hugo, Ronald J.; Jensen, Michael L.; McCrae, Kimberley A.

    2000-09-01

    Results of the (temperature) refractive index structure parameter (C2T), C2n, and the eddy dissipation rate (epsilon) derived from the velocity structure parameter C2v are presented from fast response sensor observations using a kite/tethered-blimp platform in the Tularosa Basin at White Sands Missile Range, New Mexico, during the spring of 1998. Comparisons of different sensors (fine-wire probes and pilot tubes) measuring the same parameter are displayed and discussed while salient features of all sensors (standard and fast response) and the kite and tethered-blimp platforms are outlined. The nature and statistics of turbulence, including intermittency, under different stability conditions is discussed, including those found in the residual layer above the nocturnal boundary layer and the entrainment zone at the top of the daytime planetary boundary layer. In addition to displaying time series of temperature C2n and (epsilon) results obtained at specific altitudes and times, histograms of all daytime and nighttime C2n and (epsilon) values are compared to log-normal distributions. Examples of profiles of C2n and (epsilon) for daytime, near sunset, and nighttime conditions are shown and discussed. The relationship of C2n with (epsilon) is displayed for all data as well as sorted by daytime and nighttime. These results are explained in terms of potential and kinetic energy considerations under different atmospheric stability conditions.

  17. In-situ turbulence measurements over a desert basin using a kite/tethered-blimp platform

    NASA Astrophysics Data System (ADS)

    Eaton, Frank D.; Balsley, Ben B.; Bishop, Kenneth P.; Frehlich, Rod G.; Hugo, Ronald J.; Jensen, Michael L.; McCrae, Kimberley A.

    1999-08-01

    Results of the refractive index structure parameter (CT2), Cn2, and the eddy dissipation rate, (epsilon) , derived from the velocity structure parameter, Cv2, are presented from high speed fluctuation measurements taken using a kite/tethered-blimp platform in the Tularosa Basin at White Sands Missile Range, NM during the spring of 1998. Comparisons of different sensor measuring the same parameter are displayed and discussed. Salient features of the sensors and the kite and blimp platforms are outlined. Long term measurements of high speed fluctuations of temperature and velocity are shown and intermittency of turbulence is discussed. The nature and statistics of turbulence inside, outside, and at the boundary of a turbulent layer are also shown and interpreted. Observations in the entrainment zone at the top of the planetary boundary layer are shown and similarities of characteristics found in the tropopause region with these boundary layer features is discussed. The diurnal variation of turbulence is presented with particular emphasis on the transition period from the end of daytime convection to development of the stable nocturnal boundary layer. Results are displayed as profiles and histograms of Cn2 and (epsilon) for daytime, near sunset, and nighttime conditions.

  18. Thermal shock and splash effects on burned gypseous soils from the Ebro Basin (NE Spain)

    NASA Astrophysics Data System (ADS)

    León, J.; Seeger, M.; Badía, D.; Peters, P.; Echeverría, M. T.

    2014-03-01

    Fire is a natural factor of landscape evolution in Mediterranean ecosystems. The middle Ebro Valley has extreme aridity, which results in a low plant cover and high soil erodibility, especially on gypseous substrates. The aim of this research is to analyze the effects of moderate heating on physical and chemical soil properties, mineralogical composition and susceptibility to splash erosion. Topsoil samples (15 cm depth) were taken in the Remolinos mountain slopes (Ebro Valley, NE Spain) from two soil types: Leptic Gypsisol (LP) in a convex slope and Haplic Gypsisol (GY) in a concave slope. To assess the heating effects on the mineralogy we burned the soils at 105 and 205 °C in an oven and to assess the splash effects we used a rainfall simulator under laboratory conditions using undisturbed topsoil subsamples (0-5 cm depth of Ah horizon). LP soil has lower soil organic matter (SOM) and soil aggregate stability (SAS) and higher gypsum content than GY soil. Gypsum and dolomite are the main minerals (>80%) in the LP soil, while gypsum, dolomite, calcite and quartz have similar proportions in GY soil. Clay minerals (kaolinite and illite) are scarce in both soils. Heating at 105 °C has no effect on soil mineralogy. However, heating to 205 °C transforms gypsum to bassanite, increases significantly the soil salinity (EC) in both soil units (LP and GY) and decreases pH only in GY soil. Despite differences in the content of organic matter and structural stability, both soils show no significant differences (P < 0.01) in the splash erosion rates. The size of pores is reduced by heating, as derived from variations in soil water retention capacity.

  19. Heat Flow of The NE German Basin: A Matter of Revision?

    NASA Astrophysics Data System (ADS)

    Lotz, B.; Förster, A.

    The Northeast German Basin (NEGB) is part of the Middle European Depression and comprises a sedimentary succession up to 9 km thick. Recent geophysical investiga- tions have shown that Baltic crust reaches to the south of the Caledonian Deforma- tion Front (CDF) and that strong crustal heterogeneity exists between the CDF and the Elbe line. This area of crustal heterogeneity is interpreted as the transition zone between Proterozoic and Phanerozoic European crusts where magmatic underplating occurred in Permian time. The crust here supposedly contains blocks of lower crust of Baltica that were detached and displaced during the Caledonian orogeny. To further clarify whether the crust beneath the NEGB is different in composition and to what extent crustal composition and crustal thickness affect the thermal conditions of the basin it is of interest to revisit surface heat flow. A set of widely distributed deep wells from which temperature profiles and drill cores are available is under examination yet. The Lower Permian (Rotliegend) sediments and volcanic rocks are the main target for new heat flow determinations. Obstacles for determining high-quality heat flow val- ues are the temperature data provided by the oil industry with large (50-m) recording intervals and therefore lack of detail in the temperature-depth distribution. Some tem- perature logs need to be corrected for thermal equilibrium. Other corrections concern the temperature dependence of thermal conductivity and the heat transfer around thick salt structures. For example, the temperature decrease below a salt structure of 2000- m thickness and, vice versa, the temperature increase above the salt can be observed for several hundred meters and may reach -5 to +15 C, respectively. New thermal conductivity values differ slightly to strongly from measurements made in previous studies under unknown conditions. Andesites show values of 2.2 W/m/K in corre- spondence with the older data. In contrast, previous

  20. Prospect evaluation of shallow I-35 reservoir of NE Malay Basin offshore, Terengganu, Malaysia

    NASA Astrophysics Data System (ADS)

    Janjua, Osama Akhtar; Wahid, Ali; Salim, Ahmed Mohamed Ahmed; Rahman, M. Nasir B. A.

    2016-02-01

    A potential accumulation of hydrocarbon that describes significant and conceivable drilling target is related to prospect. Possibility of success estimation, assuming discovery of hydrocarbons and the potential recoverable quantities range under a commercial development program are the basis of Prospect evaluation activities. The objective was to find the new shallow prospects in reservoir sandstone of I -Formation in Malay basin. The prospects in the study area are mostly consisting of faulted structures and stratigraphic channels. The methodology follows seismic interpretation and mapping, attribute analysis, evaluation of nearby well data i.e., based on well - log correlation. The petrophysical parameters analogue to nearby wells was used as an input parameter for volumetric assessment. Based on analysis of presence and effectiveness, the prospect has a complete petroleum system. Two wells have been proposed to be drilled near the major fault and stratigraphic channel in I-35 reservoir that is O-1 and O-2 prospects respectively. The probability of geological success of prospect O-1 is at 35% while for O-2 is 24%. Finally, for hydrocarbon in place volumes were calculated which concluded the best estimate volume for oil in O-1 prospect is 4.99 MMSTB and O-2 prospect is 28.70 MMSTB while for gas is 29.27 BSCF and 25.59 BSCF respectively.

  1. A Siliciclastic-Infilled Sedimentary Basin Within a Large Carbonate Platform, Tampa Bay, Florida

    NASA Astrophysics Data System (ADS)

    Suthard, B. C.; Hine, A. C.; Locker, S. D.; Duncan, D. S.; Morton, R. A.; Hansen, M. E.; Edgar, N. T.

    2002-12-01

    A seismic stratigraphic framework based on over 800 km of seismic reflection data collected within the Tampa Bay estuary and approximately 200 boreholes in and around the estuary shows three separate subsurface regions. In the north-central portion of the bay there is an irregular east-west oriented subsurface trough in the Miocene limestone that reaches depths of 30 m below the seafloor (mbsf). This trough contains steeply dipping clinoforms that indicate it has been filled from the south and east and borehole data show that these clinoforms are siliciclastic sediments. South of the trough in the center of Tampa Bay there is a broad carbonate bedrock high. This area is characterized by less than two meters of siliciclastic sediment cover as well as small-scale shallow karst features (10's m in width and up to 10 m in relief). In the southern portion of the Bay the seismic reflection data shows the Miocene limestone has large-scale warping as well as larger-scale karst features (100's m in width and 30+ m in relief) creating another deep basin (up to 40 mbsf) that has been filled by siliciclastics from the south and the east. The sedimentary basin underlying the modern estuary reveals that accommodation space can form within the center of large carbonate platforms and that this accommodation space may be filled by remobilized siliciclastics. Based upon the age of the underlying limestones, and recent work in south Florida by others, we propose that the Tampa Basin was filled during multiple Late Neogene and Quaternary sea-level fluctuations. Additionally, we speculate that the observed multiple buried sinkholes, and sag-and-warp deformation indicate spatially selective subsurface collapse probably initiated by deep-seated dissolution produced by karst processes. Overlying stratigraphic units subsided as a result of solution collapse, creating a surficial topographic low. This surficial basin may have controlled subsequent non-marine, estuarine and even open marine

  2. Stages in evolution of Paleozoic carbonate platform and basin margin types - western United States passive Continental Margin

    SciTech Connect

    Cook, H.E.; Taylor, M.E.

    1987-05-01

    Late Precambrian rifting along the western edge of North America established a passive continental margin that became the site of 5000 m of platform and basin carbonate sediments over a 150-m.y. interval (Cambrian-Devonian). This megaplatform evolved through several stages: (1) Cambrian-Silurian, distally steepened nonrimmed ramp with base-of-slope fan (Hales Limestone) to homoclinal ramp (Hanson Creek Formation); to (2) Silurian-Devonian, rimmed platform (Lone Mountain Dolomite) having low-angle depositional slopes and slope aprons (Roberts Mountains Formation) and basinal debris sheets (Tor Limestone); to (3) Devonian, rimmed platforms having high-angle bypass slopes, slides, and base-of-slope aprons (McColley Canyon Formation and Devils Gate Limestone). The position of the rifted continental margin controlled the overall trend of the platform-slope break. Postrift subsidence with superimposed eustatic sea level changes allowed the platform to accumulate 5000 m of sediment. The stratigraphic progression from nonrimmed ramps in the Cambrian to rimmed platforms with high-angle bypass slopes in the Devonian was a function of both the gradual steepening of the slope, as the platform margin built up and prograded seaward, and the evolution of reef and bank-building organisms through time. Evolution of adjacent basinal carbonates was strongly influenced by slope declivity and relative sea level changes. As slope declivity increased through time, sedimentary processes on the slope changed from small-scale sediment gravity flows that accreted on the slope (ex: Roberts Mountains Formation slope apron) to large-scale sediment gravity flows that deposited debris in base-of-slope settings (ex: Devils Gate Limestone base-of-slope apron).

  3. Facies patterns and stratal geometries: clues to the nature of the platform margin during the Paleocene, northeast Sirte Basin, Libya

    NASA Astrophysics Data System (ADS)

    Mresah, Mohamed H.

    1993-04-01

    The Sirte Basin of Libya is a Mesozoic—Tertiary rift basin comprising a series of horsts and grabens, which were formed as a result of collapse of a N—S trending arch in Late Cretaceous time. The Paleocene section is made up of two shallowing-upward cycles, where each cycle is under- and overlain by deeper, pelagic facies. A gradual shallowing trend from basin to shallow platform is seen in both bio- and lithofacies. These are interpreted as representing prograding ramps, with no evidence of a significant break in slope between the basin and the adjacent platform. The fact that most facies are dominated by micrites suggests that deposition was in a low-energy setting, possibly on a leeward margin. These ramps were initially foram-dominated platforms, setting the style for later Tertiary ramps, large forams filling the role of inner-mid ramp carbonate producers after the demise of the rudist—coral assemblage at the end of the Cretaceous. Based on local and regional information, a number of episodes of relative sea-level change can be recognized. The two shallowing-upward ramp cycles are interpreted as representing two highstand system tracts. The precipitation of evaporites in the lower cycle appears to be associated with the earlier highstand system tract, culminating during a sea-level lowstand. A drop in sea level during the Late Paleocene is also invoked to explain the interpreted influx of meteoric waters following the later highstand. This event resulted in the creation of good mouldic and vuggy porosities, thus making these porous, inner-mid ramp facies potential targets for hydrocarbon exploration. On a basin-wide scale, this event is also very important because all the Paleocene reservoirs, at least in the eastern Sirte Basin, seem to be related to this possible subaerial exposure event.

  4. Screening of perfluorinated compounds in water, sediment and biota of the Llobregat River basin (NE Spain)

    NASA Astrophysics Data System (ADS)

    Campo, Julian; Perez, Francisca; Pico, Yolanda; Farre, Marinella; Barcelo, Damia; Andreu, Vicente

    2014-05-01

    PFCs present significant thermal and chemical stability being persistent in the environment, where they can bio-accumulate and adversely affect humans and wildlife (Llorca et al., 2012). Human exposure to PFCs is of concern since PFCs tend to be associated with fatty acid binding proteins in the liver or albumin proteins in blood, and have been detected in human serum, urine, saliva, seminal plasma and breast milk (Sundstrom et al., 2011). This study is aimed at the screening of 21 perfluorinated compounds (PFCs) in environmental samples by high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS). The main objective is to identify target compounds at low levels in water, sediments and biota of the Llobregat River (2010), second longest river in Catalonia and one of Barcelona's major drinking water resources. PFCs were extracted from water samples by Solid Phase Extraction (SPE); from sediment by ultrasonication with acidified methanol followed by an off-line SPE procedure (Picó et al., 2012), and from biota (fish) with alkaline digestion, clean-up by TurboFlow™ on line technology coupled to LC-MS/MS (Llorca et al., 2012). The limits of detection (LODs) and limits of quantification (LOQs) of the method were calculated by analysis of spiked river water, sediment, and biota with minimum concentrations of each individual compound at a signal-to-noise ratio of 3 and 10, respectively. The LODs and LOQs of the method in river water ranged between 0.004 and 0.8 ng L-1 and between 0.01 and 2 ng L-1, respectively. In sediment LODs were 0.013-2.667 ng g-1 dry weight (dw) and LOQs were 0.04-8 ng g-1 dw, meanwhile in biota these were 0.006-0.7 pg μL-1 and 0.02-2.26 pg μL-1, respectively. Recoveries ranged between 65% and 102% for all target compounds. The method was applied to study the spatial distribution of these compounds in the Llobregat River basin. For this, a total of 40 samples were analysed (14 water, 14 sediments, 12 fishes). Of the 21 target

  5. Cycle stratigraphy and porosity in Pennsylvanian and Lower Permian shelf limestones, eastern Central Basin Platform, Texas

    SciTech Connect

    Saller, A.H.; Dickson, J.A.D.; Boyd, S.A.

    1994-12-01

    Pennyslvanian and Lower Permian shelfal limestones were studied in core and wireline logs on the eastern side of the Central Basin platform in west Texas. Sixty-three (63) cycles were delineated in the study interval, which includes 200-250 m of Canyon (Missourian), Cisco (Virgilian), and Wolfcamp strata. Four general lithofacies are present: fossiliferous wackestones and packstones, grainstones, phylloid algal boundstones, and shales. These lithologies typically occur in 1-18-m-thick cycles bounded by subaerial exposure surfaces. Grainstones in the upper part of some cycles indicate a shallowing of environments prior to subaerial exposure. Many cycles have subaerial exposure surfaces developed on subtidal fossiliferous wackestones or packstones suggesting rapid falls in sea level. Long-term transgressive intervals (transgressive systems tracts or TST) are dominated by thick (>4 m) cycles, whereas long-term regressive intervals (highstand systems tract or HST) are dominated by thinner cycles. Stable carbon isotope data suggest that thick cycles in TSTs were subjected to short periods of subaerial exposure, whereas thin cycles in the HSTs were subjected to much longer subaerial exposure. Where present, reservoir-grade porosity occurs in the upper part of cycles, 0.3-5 m below subaerial exposure surfaces. Prolonged subaerial exposure apparently reduced matrix porosity by allowing more time for calcite precipitation, which was especially effective in reducing porosity in micritic strata below exposure surfaces.

  6. Mississippian carbonate buildups and development of cool-waterlike carbonate platforms in the Illinois Basin, Midcontinent U.S.A.

    USGS Publications Warehouse

    Lasemi, Z.; Norby, R.D.; Utgaard, J.E.; Ferry, W.R.; Cuffey, R.J.; Dever, G.R., Jr.

    2005-01-01

    Numerous biohermal buildups occur in Mississippian (Lower Carboniferous) strata in the Illinois Basin and adjacent regions. They developed as mud mounds, biodetrital calcisiltite mounds, and bryozoan frame thickets (fenestrate-frame coquina or rudstone) during the Kinderhookian and early Meramecian (Tournaisian and early Visean), and as microbial mud mounds, microbial- serpulidbryozoanboundstones, and solenoporoid (red algal) boundstones during the Chesterian (late Visean and Serpukhovian). True Waulsortian mounds did not develop in the Illinois Basin, but echinoderm (primarily crinoids)-bryozoan carbonate banks and bryozoan frame thickets generally occupied the same niche during the Kinderhookian-early Meramecian. Nutrient availability and the resulting increase in the productivity of echinoderms and bryozoans were apparently detrimental to Waulsortian mound development. Deposition of crinoidal-bryozoan carbonates during the Kinderhookian-Osagean initially occurred on a ramp setting that later evolved into a platform with a relatively steep margin through sediment aggradation and progradation. By mid-Osagean-early Meramecian, two such platforms, namely the Burlington Shelf and the Ullin Platform, developed adjacent to a deep, initially starved basin. Sedimentologic and petrographic characteristics of the Kinderhookian-earliest Meramecian carbonates resemble the modern cool-water Heterozoan Association. This is in contrast with post-earliest Meramecian carbonates, which are typically oolitic and peloidal with common peri tidal facies. The post-earliest Meramecian carbonates, therefore, resemble those of the warm-water Photozoan Association. The prevalence of Heterozoan carbonates in the Illinois Basin correlates with a rapid increase in the rate of subsidence and a major second-order eustatic sea-level rise that resulted in deep-water starved basins at this time. In the starved Illinois Basin, deposition was initially limited to a thin phosphatic shale that was

  7. Reconstruction of Sea/Lake-Level Changes in an Active Strike-Slip Basin (Gulf of Cariaco, NE Venezuela)

    NASA Astrophysics Data System (ADS)

    van Daele, M.; Audemard, F.; Beck, C.; de Batist, M.; van Welden, A.; Moernaut, J.; 2006 Shipboard Party, G.

    2008-05-01

    . According to this age model, our seismic stratigraphy reaches back to MIS6, and the average sedimentation rate in the central parts of the gulf since MIS5e is 0.92 mm/y. Our data show that reconstructed lake levels in the Gulf of Cariaco, which represent a proxy for climate in NE- Venezuela, are very strongly coupled to the global stadials and interstadials of the last glacial period. Also the Younger Dryas is recognised in the sedimentary record of the Gulf of Cariaco as lowstand deposit resulting from an (almost) complete desiccation. Our data reveal that the stratigraphy of the Gulf of Cariaco holds a very accurate, complete and promising record of eustasy and climate change, at least since the penultimate glacial maximum. The quality of this record and the vicinity to the iconic Cariaco Basin make the Gulf of Cariaco an ideal target for future ocean drilling (or long coring).

  8. Platforms.

    PubMed

    Josko, Deborah

    2014-01-01

    The advent of DNA sequencing technologies and the various applications that can be performed will have a dramatic effect on medicine and healthcare in the near future. There are several DNA sequencing platforms available on the market for research and clinical use. Based on the medical laboratory scientist or researcher's needs and taking into consideration laboratory space and budget, one can chose which platform will be beneficial to their institution and their patient population. Although some of the instrument costs seem high, diagnosing a patient quickly and accurately will save hospitals money with fewer hospital stays and targeted treatment based on an individual's genetic make-up. By determining the type of disease an individual has, based on the mutations present or having the ability to prescribe the appropriate antimicrobials based on the knowledge of the organism's resistance patterns, the clinician will be better able to treat and diagnose a patient which ultimately will improve patient outcomes and prognosis. PMID:25219075

  9. Patterns of landscape form in the upper Rhône basin, Central Swiss Alps, predominantly show lithologic controls despite multiple glaciations and variations in rock uplift rates

    NASA Astrophysics Data System (ADS)

    Stutenbecker, L. A.; Costa, A.; Schlunegger, F.

    2015-10-01

    The development of topography is mainly dependent on the interplay of uplift and erosion, which are in term controlled by various factors including climate, glaciers, lithology, seismic activity and short-term variables such as anthropogenic impact. While most studies have focused on the role of tectonics and climate on the landscape form and underlying processes, less attention has been paid on exploring the controls of lithology on erosion. The Central European Alps are characterized by a large spatial variability in exposed lithologies and as such offer an ideal laboratory to investigate the lithological controls on erosion and landscape form. Here, we focus on the ca. 5400 km2-large upper Rhône basin situated in the Central Swiss Alps to explore how the lithological architecture of the bedrock conditions the Alpine landscape. To this extent, we extract geomorphological parameters along the channels of ca. 50 tributary basins, whose catchments are located in either granitic basement rocks (External massifs), oceanic meta-sedimentary and ophiolitic rocks (Penninic nappes) or fine-grained continental-margin sediments (Helvetic nappes). The analysis of longitudinal river profiles show that all tributary rivers within the Rhône basin are in topographic transient state as testified by mainly convex or concave-convex longitudinal stream channel profiles with several knickpoints of either tectonic or glacial origin. In addition, although the entire Rhône basin shows a strong glacial inheritance (and is still partly glaciated) and some of the highest uplift rates recently measured in the Alps, the river network has responded differently to those perturbations as revealed by the morphometric data. In particular, tributary basins in the Helvetic nappes are the most equilibrated (concave river profiles, overall lower elevations, less steep slope gradients and lowest hypsometric integrals), while the tributaries located in the External massifs are least equilibrated

  10. Genetic sequence relationships of Winnipegosis platform carbonates, Southern Elk Point basin, North Dakota

    SciTech Connect

    Shanley, K.W.; Cross, T.A.

    1988-07-01

    Examination of cores and well-log data from the Winnipegosis Formation (Givetian) within a study area of approximately 11,500 mi/sup 2/ (30,000 km/sup 2/) in northern North Dakota allows recognition of seven time-stratigraphic progradational units within the Winnipegosis Formation. Together with the underlying Ashern Formation, these units are arranged in landward-stepping, vertical stacking, and seaward-stepping geometric patterns, which reflect changes in relative sea level. Abrupt juxtaposition of shallow over deeper water lithologies, evidence for subaerial exposure, and onlap geometries further suggest that these progradational units form two larger Vail-type sequences separated by regionally persistent unconformities or their correlative conformities. Sea level rise during the early Eifelian caused southeastward onlap of the Ashern Formation onto Middle Silurian carbonates of the Interlake Formation. Maximum flooding, expressed by deepest marine facies and a hardground surface, suggests the existence of a condensed section at the top of the Ashern Formation. This section was developed during the maximum rate of sea level rise. A decrease in the rate of sea level rise resulted in aggradation of lower Winnipegosis units on a gently dipping ramp. These units are presented by nodular and burrowed open-marine limestones with scattered stromatoporoid patch reefs and grainstone shoals. During the subsequent sea level fall, represented by Temple units, a shelf margin with pronounced depositional topography and adjacent starved basin were developed. Temple strata include coral-brachiopod-stromatoporoid reefs and productive fore-reef talus deposits along the shelf-margin rim. With increased rates of sea level fall, the platform interior and shelf margin were subaerially exposed, slope carbonates were dolomitized, and the E-shale was deposited as a lowstand wedge.

  11. Landscape response to recent tectonic deformation in the SW Pannonian Basin: Evidence from DEM-based morphometric analysis of the Bilogora Mt. area, NE Croatia

    NASA Astrophysics Data System (ADS)

    Matoš, Bojan; Pérez-Peña, José Vicente; Tomljenović, Bruno

    2016-06-01

    Bilogora Mt. area is a transpressional structure located in the NE of Croatia, linked with the tectonic evolution of the Drava Depression. The structure formed during Pliocene and Quaternary from the inversion of NW-striking Drava Depression Boundary Fault, which originated as a normal fault and was reactivated as a dextral strike-slip fault. During Pliocene and Quaternary time, Bilogora Mt. area underwent more than 400 m of differential uplift, while still ongoing tectonic deformation is documented by historical and instrumental seismicity (3.5 ≤ ML ≤ 5.6). In this geomorphic study, the recent deformation in the Bilogora Mt. area, although obscured by landscape evolution variables, was assessed using DEM-based landscape morphometry and a set of morphometric indexes. Local relief and slope angle variability distributions were combined with morphometric indexes computed at the scale of the drainage basin. We analyzed hypsometric curves with the hypsometric integral (HI), basin asymmetry (AF) and parameters of longitudinal stream profiles (Cf, Cmax, Δl/L, θ, and ksn). Analyzed morphometric parameters were combined into a cumulative index of relative tectonic activity (RTA). This index summarizes drainage basin response to the possible recent tectonic activity. Results suggest that most of the tectonic activity is probably located along the NE front of the Bilogora Mt. area, in its NW and central part. This activity could be likely related to recent tectonic activity along the Kalnik Mt. Fault zone and Drava Depression Boundary Fault zones, respectively. A subordinate area characterized by recent tectonic activity could be suggested within the southernmost part of the study area. Quaternary activity in this area is probably related to NE-striking faults in vicinity of the town Daruvar that continue towards the northeast into the study area. Though methodology presented here represents a good identification tool of possible ongoing deformation, this study will be

  12. 3-D seismic analysis of a carbonate platform in the Molasse Basin - reef distribution and internal separation with seismic attributes

    NASA Astrophysics Data System (ADS)

    von Hartmann, Hartwig; Buness, Hermann; Krawczyk, Charlotte M.; Schulz, Rüdiger

    2012-10-01

    Carbonate platforms differ from clastic sedimentary environments by a greater heterogeneity, so that key horizons for mapping and compartmentalisation of the reservoir are generally missing. We show that different seismic attributes help to compete with these difficulties and to identify different carbonate facies within the platform. The Upper Jurassic carbonate platform in Southern Germany in the Molasse Basin is a main exploration target for hydrogeothermal projects. Knowledge about the distribution of different carbonate facies within the platform, which is overprinted by faults, is important for a realistic reservoir simulation. The platform with an average thickness of 600 meters was artificially divided into four layers of equal thickness. Within each layer the characteristic seismic pattern was visualized by different attributes (travel time mapping, spectral decomposition), allowing additionally for further depositional classification. Within the uppermost layer the coral reef distribution could be mapped. The reefs form several complexes of up to 12 square kilometres in size. The surrounding slope and trough areas are identified as well. Within the platform , the distribution of sponge reefs could be visualized. They form either amalgamations in distinct areas, or are spread as small singular structures with diameters of approximately less than hundred meters. Comparing tectonic elements and reef distribution within the whole platform reveals that the early topography triggered the reef distribution, while these lithologic inhomogenities influenced later on the local shape of tectonic lineaments. The fault system which dominates the structural style in the area is visible in the different transformations but does not obscure the facies distribution, which hindered former interpretations of the data set. In this way a reservoir model can incorporate now the first time the reef distribution within an area.

  13. The Bartonian-Priabonian marine record of the Eastern South Pyrenean Foreland Basin (NE Spain): A new calibration of the larger foraminifers and calcareous nannofossil biozonations.

    NASA Astrophysics Data System (ADS)

    Costa, E.; Garcés, M.; López-Blanco, M.; Serra-Kiel, J.; Bernaola, G.; Cabrera, L.; Beamud, E.

    2012-04-01

    The up to 5000-m-thick sedimentary infill of the South Pyrenean Foreland Basin (in NE Spain) records the Cenozoic evolution of the NE Iberian plate. This region is an excellent area where to perform a combined biomagnetostratigraphic study of a Paleogene succession as the present level of erosion of the basin infill and its surrounding mountain ranges is at an optimal stage for studying a continuous and thick stratigraphic record. In this sense, a biochronological framework of the South Pyrenean Foreland Basin has been developed since the early 1950's, which was later combined with magnetostratigraphic studies. This biochronological framework, together with all the available literature on the biostratigraphy and magnetostratigraphy of the Paleocene and Eocene Tethys, were integrated in a general chronostratigraphic framework used to define and calibrate the larger foraminifer biozonation (Shallow Benthic Zones, SBZ). However, in the Gelogical Time Scale 2004 no correlation of the Paleogene SBZ zonation with the geomagnetic polarity time scale was provided. Here we present a combined biostratigraphic (larger foraminifers, calcareous nannofossils) and magnetostratigraphic study of the Middle and Late Eocene marine units of the Igualada area, on the eastern Ebro Basin. The studied sections of Santa Maria de Miralles and La Tossa encompass the complete marine succession of the Santa Maria Group. A total of 224 paleomagnetic sites and 64 biostratigraphic samples were collected along a 1350-m-thick section that ranges from chron C20n to chron C16n (ca. 43-36 Ma). The resulting magnetostratigraphy-based chronology challenges existing chronostratigraphic interpretations of these units and results in a new calibration of the larger foraminifers and calcareous nannofossil biozonations. The traditional division of the Bartonian stage into two complete larger foraminifers zones, SBZ17 and SBZ18, is challenged. Zone SBZ17 embraces most of the Bartonian, while Zone SBZ18 extends

  14. Drainage architecture and sediment routing in erosive catchments within the Ebro Eiver sedimentary basin (NE Iberian Peninsula)

    NASA Astrophysics Data System (ADS)

    Castelltort, Xavier; Colombo, Ferran; Carles Balasch Solanes, Josep

    2016-04-01

    The Ebro Basin (EB) is the result of filling a foreland basin located between active mountain ranges during the Paleogene compressive phases, and later affected by phases of distension in the Neogene. The arrangement of filler material is monocline in the eastern margin and in the contact with the Catalan Coastal Range (CCR). This has repercussions on the model of emptying the erosive basins and in the drainage that took place in the margins of the original sedimentary basin. One can speak of a drainage architecture and sediment routing associated to a monocline erosive basin model. The monocline topography in the original margin of EB encouraged the formation of a string of erosive basins around the contact with CCR, which are the result of headward erosion towards the center of the EB of the rivers draining the CCR towards the Valencia Trough. At the time, the transition from the EB in its initial condition of endorheic to exorheic was through one of these monocline erosive basins. The erosive basins emptied by means of two vectors. On the one hand, growth in surface of the basin by deepening anaclinal streams through resistant beds of monocline stratigraphic succession that empty and link small depressions that increase laterally on the less resistant lithologic member. Moreover, the new drainage system entrenches as the exit point of the basin does, thanks to gradients created by distensional movements of the Neogene Valencia Trough. Growth and entrenchment model of river basins, as well as, sedimentary deposits and landforms generated by these processes are described and analyzed.

  15. Integrated Analysis on Gravity and Magnetic Fields of the Hailar Basin, NE China: Implications for Basement Structure and Deep Tectonics

    NASA Astrophysics Data System (ADS)

    Sun, B.; Wang, L.; Dong, P.; Scientific Team Of Applied Geophysics

    2010-12-01

    The Hailar Basin is one of the most representative basins among the Northeast China Basin Group, which is situated in the east of East Asia Orogene between the Siberia Plate and the North China Plate. Based on the detailed analysis of the Bouguer gravity anomaly, aeromagnetic anomaly as well as petrophysical data, we studied the features of gravity-magnetic fields in the basin and its neighboring areas. A combined approach of Wavelet Multi-scale Decomposition and Power Spectrum Analysis was adopted to quantitatively grade the gravity and magnetic anomalies into four levels. Accordingly, the apparent depths of the source fields can be assessed. The results reveal the crustal density and magnetic structures of the Hailar Basin. Low-order wavelet details of gravity-magnetic anomalies were carried out on studying basin basement structure. Seven major basement faults of the basin were identified, and the basement lithology was discussed and predicted. Three major uplifts and 14 depressions were delineated according to basement depth inversion by the Park method. High-order wavelet approximations of gravity-magnetic anomalies were carried out on studying deep tectonics of the basin. The average Moho depth of the study area is about 40 km, with a mantle uplift located in the northeast of the basin. The average depth of the Curie interface is about 19 km, while the uplift of the Curie interface is in the basin center and its east and west sides are depressions. Finally, inversion of Bouguer gravity anomalies was conducted on an across-basin GGT profile using the Wavelet Multi-scale Decomposition. The inversion results are consistent with those of GGT seismic inversion, suggesting that the Wavelet Multi-scale Decomposition can be applied to distinguish major crustal density interfaces.

  16. Late Cenozoic deformation of the Da'an-Dedu Fault Zone and its implications for the earthquake activities in the Songliao basin, NE China

    NASA Astrophysics Data System (ADS)

    Zhongyuan, Yu; Peizhen, Zhang; Wei, Min; Qinghai, Wei; Limei, Wang; Bin, Zhao; Shuang, Liu; Jian, Kang

    2015-08-01

    The Da'an-Dedu Fault Zone is a major tectonic feature cutting through the Songliao Basin from south to north in NE China. Five earthquakes with magnitudes over 5 that occurred during the past 30 years suggest the fault zone is a seismogenic structure with future seismic potential. The structural pattern, tectonic history, Quaternary activity and seismic potential have previously been unknown due to the Quaternary sedimentary coverage and lack of large historic earthquakes (M > 7). In this paper, we use seismic reflection profiles and drilling from petroleum explorations and shallow-depth seismic reflections to study those problems. The total length of the Da'an-Dedu Fault Zone is more than 400 km; modern seismicity delineates it into 4 segments each with a length of 90-100 km. In cross-section view, the folds and associated faults form a complex structural belt with a width of more than 10 km. Shallow-level seismic reflection across the Da'an-Dedu Fault Zone reveals that the Late Quaternary sediments were folded and faulted, indicating its present tectonic activity. The Da'an-Dedu Fault Zone and Songliao Basin have been subjected to three stages of tectonic evolution: a rifting stage characterized by normal faulting and extension (∼145-112 Ma), a prolonged stage of thermal subsidence (∼112-65 Ma), and a tectonic reversal that has been taking place since ∼65 Ma. Our shallow-level reflection profiles show that the folding and reverse faulting have influenced the Late Quaternary sediments. The seismicity and moderate earthquakes suggest that the tectonic activity persists today. The deformation rate across the Da'an-Dedu Fault Zone, however, is measured to be very slow. In conjunction with the inference that most deformation in NE China may be taken up by the Yilan-Yitong Fault Zone bounding the Songliao Basin to the east, we suggest moderate earthquake potential and thus moderate seismic hazards along the Da'an-Dedu Fault Zone. The geological structures, which

  17. Principles and Best Practices Emerging from Data Basin: A Data Platform Supporting Scientific Research and Landscape Conservation Planning

    NASA Astrophysics Data System (ADS)

    Comendant, T.; Strittholt, J. R.; Ward, B. C.; Bachelet, D. M.; Grossman, D.; Stevenson-Molnar, N.; Henifin, K.; Lundin, M.; Marvin, T. S.; Peterman, W. L.; Corrigan, G. N.; O'Connor, K.

    2013-12-01

    A multi-disciplinary team of scientists, software engineers, and outreach staff at the Conservation Biology Institute launched an open-access, web-based spatial data platform called Data Basin (www.databasin.org) in 2010. Primarily built to support research and environmental resource planning, Data Basin provides the capability for individuals and organizations to explore, create, interpret, and collaborate around their priority topics and geographies. We used a stakeholder analysis to assess the needs of data consumers/produces and help prioritize primary and secondary audiences. Data Basin's simple and user-friendly interface makes mapping and geo-processing tools more accessible to less technical audiences. Input from users is considered in system planning, testing, and implementation. The team continually develops using an agile software development approach, which allows new features, improvements, and bug fixes to be deployed to the live system on a frequent basis. The data import process is handled through administrative approval and Data Basin requires spatial data (biological, physical, and socio-economic) to be well-documented. Outreach and training is used to convey the scope and appropriate use of the scientific information and available resources.

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

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

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

  19. Platform-margin and marginal slope relationships and sedimentation in Devonian reef complexes of Canning basin, Western Australia

    SciTech Connect

    Playford, P.E.; Kerans, C.; Hurley, N.F.

    1984-04-01

    Devonian limestone platforms in the Canning basin were generally rimmed by reef-margin and reef-flat deposits, constructed by stromatoporoids, algae, and corals in the Givetian and Frasnian, and by algae in the Famennian. However, some platforms were low-relief banks with little or no reef development. The reefs and slowly deposited parts of the marginal-slope facies were subject to pervasive early submarine cementation by fibrous high-magnesium calcite (now radiaxial spar). The strongly cemented reef limestones formed rigid wave-resistant rims to the platforms. Fracturing of these limestones, probably largely associated with earthquake shaking, gave rise to extensive networks of neptunian dikes and sills, and to the collapse of some sections of the margins. Such collapses in turn initiated debris flows and the deposition of allochthonous reef blocks on the adjoining marginal slopes. The reef complexes are being explored extensively for lead-zinc deposits in outcrop and oil in the subsurface. A significant oil discovery was made in a Famennian platform margin (the Blina field) in 1981.

  20. NE-RESM: An Integrated Water Resource Assessment and Solutions Platform for the U.S. Northeast

    NASA Astrophysics Data System (ADS)

    Vorosmarty, C. J.; Miara, A.; Rosenzweig, B.; Duchin, F.; Dileki, N.; Stewart, R.; Wollheim, W. M.; Melillo, J. M.; Kicklighter, D. W.; Fekete, B. M.; Yang, P.; Gonzalez, J.

    2013-12-01

    Recent analysis of inland water systems using high-resolution maps depicting a wide array of stressors unveils a pattern of threat to the world's fresh water resource base upon which much of the human water supply and aquatic biodiversity depend. A characteristic pattern of management is evident in the contemporary setting, through which impairment accumulates as a function of wealth, but is then remedied by costly, after-the-fact technological investments. The Northeast region of the United States serves as an ideal example of major changes that have taken place with respect to the global hydrologic cycle. Over the course of this century, the region will be significantly impacted by both climate change and strategic management decisions focused often on near-term solutions but with potential century-scale legacy effects. We report on development of a Regional Earth System Model for the Northeast (NE-RESM), an NSF-funded project that assembles an interdisciplinary research team from academia and government with expertise in physics, biogeochemistry, engineering, energy, economics, and policy. Major components of this work include: (i) downscaled atmospheric model outputs to drive terrestrial-aquatic ecosystem models, (ii) geospatial modeling of anthropogenic greenhouse gas emissions and biotic source/sinks, (iii) a meso-economic input-output model to evaluate the impacts of ecosystem services constraints on the economy, (iv) a linked ecosystem services accounting tool, and (v) policymaker engagement. This paper will report on one set of experiments focusing on the nexus of energy, water and the economy and how it is impacted by climate constraints and environmental regulations (i.e., Clean Water Act). We identify climate and regulatory-based limits on regional power output. At the same time, we can demonstrate opportunities to better manage the nearly 400 power plants comprising the region's thermoelectric sector. These opportunities arise from analysis of power

  1. Chronology of the Final Marine Regression in the Eastern Ebro Basin: Late Eocene to Early Oligocene Tectonosedimentary Evolution. (NE Spain)

    NASA Astrophysics Data System (ADS)

    Costa, E.; Garces, M.; Saez, A.; Lopez-Blanco, M.; Beamud, E.; Gomez-Paccard, M.; Cabrera, L.

    2007-12-01

    The Ebro Basin is a triangular shaped foreland basin surrounded by three alpine ranges: the Pyrenees to the north, the Iberian Range to the SW and the Catalan Coastal Range to the SE. During the early Paleocene started the development of the Ebro Basin by flexural subsidence related to the growth of its margins as a consequence of the continental collision of Iberia and Europe. Connection of the Ebro Basin with the open sea was maintained until late Eocene, when ongoing convergence along the Pyrenean margin lead to the final closure of its western connection with the Atlantic Ocean. Since then, a long endorheic period of uninterrupted continental sedimentation leads to the accumulation of a thick sequence composed by alluvial and lacustrine facies. In foreland basins, tectonics plays a fundamental role in the sedimentation, by generating relief in the margins and accommodation space in the basin. Therefore, it is generally assumed that the main sedimentary breaks have a tectonic origin. The tectonic control on the sedimentation has been successfully established along the margins of the Ebro Basin through the study of the geometries of the syntectonic sediments. However, away from the margins, in distal alluvial and lacustrine environments some other factors related to the climate can also exert control on the sedimentation. In order to interpret the sedimentary record of the Ebro Basin in terms of tectonosedimentary and paleoclimatic evolution, we have sampled two magnetostratigraphic sections (1000 m and 600 m, thick) on Eocene-Oligocene continental sequences. Samples were collected at 2-5 m stratigraphic intervals. Stepwise thermal demagnetisation of the NRM of up to 2 samples per site has yielded a local magnetic polarity stratigraphy. Unambiguous correlation with the geomagnetic polarity time scale was feasible based on the presence of late Eocene to early Oligocene mammal fossil localities and previous magnetostratigraphic studies spanning the complete

  2. Geologic map of the Alligator Ridge area, including the Buck Mountain East and Mooney Basin Summit quadrangles and parts of the Sunshine Well NE and Long Valley Slough quadrangles, White Pine County, Nevada

    USGS Publications Warehouse

    Nutt, Constance J.

    2000-01-01

    Data set describes the geology of Paleozoic through Quaternary units in the Alligator Ridge area, which hosts disseminated gold deposits. These digital files were used to create the 1:24,000-scale geologic map of the Buck Mountain East and Mooney Basin Summit Quadrangles and parts of the Sunshine Well NE and Long Valley Slough Quadrangles, White Pine County, east-central Nevada.

  3. Alternating Wind and Fluvial Erosion during the Quaternary in the Qaidam Basin (NE Tibetan Plateau) and its tectonic and climatic significance

    NASA Astrophysics Data System (ADS)

    Wu, L.; Xiao, A.

    2014-12-01

    The Qaidam Basin is located in the NE Tibetan Plateau, and trapped by the Altyn Tagh Fault system to the northwest, the Qilian Mts. to the northeast and the East Kunlun Mts. - Qiman Tagh to the south. It forms one of the driest regions on earth with severe wind erosion since ca. 3.0 Ma (Heermance et al., 2013). Whether the Qaidam Basin is one of the major sources of the Chinese Loess Plateau is still debating: study on U-Pb ages of zircon crystals favored the positive answer (Pullen et al., 2011), whereas chemical and mineralogical analysis (Sun, 2002), together with observation on dust storms over the past 50 years (Sun et al., 2001), preferred the negative one. Kapp et al. (2011) reconciled the two contrasting viewpoints by numerical modeling based on the assumption that the Qaidam Basin underwent strong wind erosion during glacial periods but weak wind erosion even fluvial deposition during interglacial periods. However, no geological evidences have been found to back up the assumption. In this contribution, we reported geological evidence indicating that alternating wind erosion and fluvial deposition do exist in the western Qaidam Basin. The evidence consists of an isolated alluvial fan overlying old yardangs forming prior to the fan. The fan, as well as the underlying old yardangs, is now tens of meters higher than adjacent area which is full of young yardangs, suggesting that the fan was deposited between the two wind erosion events. We obtained high resolution (<10cm) DEM data of the fan and adjacent area by terrestrial LiDAR scanning and the age of the fan by 10Be exposure dating (test in process). We will use the results to calculate the long-term wind erosion rate in the Qaidam Basin, which is the first wind erosion rate obtained from accurate geological evidence. We believe that the result is significant to evaluate the impact of wind erosion on folding inside the basin, and of the global glacial - interglacial cycles on surface processes in the

  4. Crustal thickness beneath the Chaco-Parana basin, NE Argentina, from surface waves and ambient noise tomography

    NASA Astrophysics Data System (ADS)

    Rosa, M.; Collaco, B.; Sanchez, G.; Assumpcao, M.; Sabbione, N.

    2013-05-01

    We present the results of a study of surface-wave dispersion data obtained by group velocity tomography, using seismic data and ambient seismic noise correlation, for the region of the Chaco-Parana basin, a Neopaleozoic intracratonic basin, formed by a complex history of different processes of subsidence. Previous surface waves analysis (e.g., Feng et al., 2004, 2007; Snokes and James, 1997) estimated Moho depth in the central Chaco basin and a low-velocity anomaly in the lithospheric mantle. However the seismic structure of the crust and upper mantle remains little characterized across the region due to the rather poor resolution, especially for the south region. The aim of this work is to improve the resolution and fidelity of crustal images obtained from traditional earthquake-based measurements. Hence, we have increased the number of group velocity measurements using data from regional earthquakes recorded at LPA (La Plata) station, Brazilian Seismic Network stations (BRASIS), permanent (GSN) and portable (BLSP) stations as well as inter-station dispersion curves derived from a dataset of seismic noise recordings from BRASIS, INPRES stations, LPA, CPUP and TRQA stations. The resulting path coverage is denser and displays a more uniform azimuthally distribution producing better tomographic images. The dispersion curves were obtained by a multiple filter technique (Dziewonski et al, 1969) using a phase-matched filter. A 2D group velocity tomographic inversion was performed, applying a conjugate-gradient method (Paige and Saunders, 1982). The group velocity maps for 10 to 120 seconds correspond very well to tectonic structures throughout the studied area and the resolution was improved in northern Argentina and southern Brazil by the better seismic ray coverage showing low-velocity anomalies in the upper-mantle beneath the Chaco basin, compatible with other dispersion results. The new group velocity maps were inverted for S velocity structures, using a

  5. Geophysical evidence of crustal-heterogeneity control of fault growth in the Neocomian Iguatu basin, NE Brazil

    NASA Astrophysics Data System (ADS)

    de Castro, David L.; Bezerra, Francisco H. R.; Castelo Branco, Raimundo M. G.

    2008-11-01

    Models of fault growth propose that rift initiation starts with short fault segments. Knowledge of the growth of these segments and their interactions is important to understanding rift geometry and evolution. In the northern part of the Borborema Province, northeastern Brazil, a continental-scale, Cretaceous extensional system of faults has been observed to have reactivated ductile Precambrian shear zones. The faults form small grabens that represent the rift stage of the sedimentary basins. We integrated airborne radiometric and magnetic data with terrestrial gravity survey to investigate the influence of crustal heterogeneity on fault growth and the development of the extensional faults in one of these grabens, the Iguatu basin. Previous studies presented geophysical data, which provide evidence that the Iguatu basin contains a half-graben geometry. In our study, gravity and airborne geophysical data indicate that the basement of the Iguatu basin is part of a heterogeneous structural framework composed of two structural domains, is affected by several ductile shear zones and intruded by a few granite bodies. The gravity modeling reveals that this basin is composed of three right-bend en echelon fault segments. They form a sigmoid system of normal faults that accommodate the strong ˜90° bend of the Precambrian shear zones from E-W to roughly N-S. The growth of these segments led to the generation of two isolated depocenters. The overlapping fault segments link through relay ramps. Release faults that are nearly perpendicular or oblique to the three main fault segments form marginal strike ramps and horst structures in both depocenters. 3D-gravity modeling incorporates the presence of interfering sources of a heterogeneous structural framework. The modeling reveals a maximum sedimentary cover 1620 m thick, which occurs at the bend of the reactivated shear zones. The gravity signature of a possible granite body, after removal of the gravity effect of the basin

  6. Detrital Zircon Ages from Late Jurassic-Early Cretaceous Myrgovaam Basin Sandstones (Rauchua Trough), Western Chukotka, NE Russia

    NASA Astrophysics Data System (ADS)

    Miller, E. L.; Toro, J.; Gehrels, G.; Tuchkova, M.; Katkov, S.

    2004-12-01

    Late Jurassic to Early Cretaceous Myrgovaam Basin sediments (previously Rauchua Trough) are regionally significant because of the stratigraphic constraints they provide on the age and progression of deformation in the Chukotka fold belt, a possible along-strike continuation of the Alaskan Brooks Range fold-and-thrust belt. Existing descriptions of the structural and stratigraphic relations of Myrgovaam Basin sediments to underlying strata are contradictory. Some maps portray the basin fill as deposited unconformably over deformed Triassic and Jurassic strata of the Chukotka fold-belt. In other publications, the deposits are described as structurally detached and imbricated by N-verging thrust sheets (Baranov, 1996). Field studies reveal that underlying strata are tightly folded compared to overlying strata and that the contact is a structural discordance not an unconformity. More locally, we observed arkosic sandstones typical of the Myrgovaam Basin interbedded with underlying Late Jurassic strata or present as submarine channel deposits cut into older rocks, suggesting an original stratigraphic relationship. To reconcile these observations we suggest regional deformation post-dates deposition of Myrgovaam Basin deposits, and that the disharmony in deformational style between underlying thin-bedded Triassic sandstones and shales and (stratigraphically) overlying massive quartzites, is due to their different mechanical properties. Petrographic studies indicate that fine-grained Triassic-early Jurassic sandstones represent a distal recycled orogen source, while Myrgovaam Basin sandstones originated from a proximal orogenic source containing granitoid and crystalline basement rocks (microcline, biotite, muscovite and fragments of multiply deformed schist) and intermediate to felsic volcanic rocks. Laser Ablation ICPMS was used to date zircons (100 grains) from sandstones of the Myrgovaam Basin and compare them to those in Triassic sandstones (300 grains) and verify

  7. Pliocene-Pleistocene stepwise drying of Central Asia: Evidence from paleomagnetism and sporopollen record of the deep borehole SG-3 in the western Qaidam Basin, NE Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Cai, Maotang; Fang, Xiaomin; Wu, Fuli; Miao, Yunfa; Appel, Erwin

    2012-08-01

    Drying of the Asian interior has generally been linked to Tibetan Plateau uplift, retreat of the Para-Tethys Sea and global cooling. However, lack of detailed aridification records hinders elucidation of how drying is controlled by these factors and to what extent each factor contributes. In this study, a 600 m deep core (SG-3) of lacustrine-playa deposits was obtained from the western Qaidam Basin, NE Tibetan Plateau for pollen analysis. Magnetostratigraphic dating of the core determines its age at ca. 3.1-0.01 Ma. The palynologic compositions show that a steppe to desert vegetation predominates the core. Artemisia-dominated steppe representative of relative warm and wet climate before 2.6 Ma changed to Chenopodiaceae-dominated steppe desert under drier climate conditions between 2.6 Ma and 0.9 Ma, interrupted by a short moister interval of Artemisia-dominated steppe at 1.8-1.2 Ma. From 0.9 Ma to 0.6 Ma, Chenopodiaceae-Ephedraceae desert vegetation started to develop, and since 0.6 Ma, Ephedraceae-dominated desert prevailed. This vegetation change in the western Qaidam Basin suggests a stepwise long-term aridification of the central Asia inland beginning at ca. 2.6 Ma, 1.2 Ma, 0.9 Ma and 0.6 Ma since the late Pliocene, most probably as a response to both long-term global cooling and Tibetan Plateau uplift at those times.

  8. Petroleum geology and total petroleum systems of the Widyan Basin and Interior Platform of Saudi Arabia and Iraq

    USGS Publications Warehouse

    Fox, James E.; Ahlbrandt, Thomas S.

    2002-01-01

    The Widyan Basin-Interior Platform Province (2023) ranks 17th in the world, exclusive of the United States, with 62.5 billion barrels of oil equivalent of total petroleum endowment (cumulative production plus remaining petroleum plus estimated mean undiscovered volumes). Mean estimates of undiscovered petroleum for the province, which includes both Paleozoic and Jurassic petroleum systems as well as portions of three additional total petroleum systems from adjacent provinces, are 21.22 billion barrels of oil, 94.75 trillion cubic feet of gas (15.8 billion barrels of oil equivalent), and 6.85 billion barrels of natural gas liquids. The Paleozoic total petroleum system is dominantly gas prone, whereas the volumetrically larger Jurassic total petroleum system is oil prone - resulting in the characterization of the province as an oil province. The discovery maturity for the province is a relatively low 31 percent, meaning that much of the province petroleum potential lies in the future.

  9. Geomorphological response of a landscape to long-term tectonic and glacial processes: the upper Rhône basin, Central Swiss Alps

    NASA Astrophysics Data System (ADS)

    Stutenbecker, Laura; Schlunegger, Fritz

    2015-04-01

    The Rhône River in the Central Swiss Alps drains a 5380 km2 large basin that shows a high spatial variability of bedrock lithology, exhumation rate, glacial conditioning and climate. All of these factors were recently discussed to control erosion rates in orogenic settings in general, and particularly in the Alps (e.g. Wittmann et al. 2007, Vernon et al. 2008, Norton et al. 2010a). Thanks to various and densely distributed data, the upper Rhône basin located between the Aar massif and Lake Geneva is a suitable natural laboratory to analyze the landscape's geomorphological state and controlling factors at a basin-scale. In this study, we extract geomorphological parameters along the channels of ca. 50 tributary basins of various sizes that contribute to the sediment budget of the Rhône River either through sediment supply by torrents or debris flows. Their catchments are located in either granitic basement rocks (External Massifs), oceanic meta-sedimentary and ophiolitic rocks (Penninic nappes) or fine-grained continental-margin sediments (Helvetic nappes). The analysis of longitudinal river profiles from DEMs and slope/area relationships show that all tributary rivers within the Rhône basin are in topographic transient state that is expressed by mainly convex or concave-convex channel shapes with several knickpoints of either tectonic-lithological or glacial origin. Furthermore, the frequency distribution of elevations (hypsometry) along the river channel allows identifying glacially inherited morphologies and the recent erosional front. The combination of those different geomorphological data yields to a categorization of the tributary rivers into three endmember groups: (1) streams with highly convex profiles, testifying to a strong glacial inheritance, (2) concave-convex channels with several knickzones and inherited morphologies of past glaciations, (3) predominantly concave, relatively steep rivers with minor knickpoints and inner gorges. Assuming that

  10. Tectonic and paleoclimate evolution at the NE Tibetan Plateau from 2.8 to 0.1 Ma deduced from a drill-core in Qaidam Basin

    NASA Astrophysics Data System (ADS)

    Appel, E.; Fang, X.; Zhang, W.; Song, C.; Pross, J.; Koutsodendris, A.; Li, M.; Han, W.; Hu, S.; Cirpka, O. A.; Wang, J.; Yang, Y.

    2011-12-01

    Two drillings into the lacustrine sediments of the western Qaidam Basin, with a core recovery rate of about 95%, were performed by a joint Sino-German project in order to obtain high-resolution information on paleoclimate and tectonic evolution at the NE Tibetan Plateau. Using detailed magnetostratigraphy and OSL the ca. 940 m long core SG-1 was dated at 0.1 to 2.8 Ma while the ca. 720 m long core SG-1b (located in a 20 km distant anticline) spans the period from 1.7 to 7.2 Ma. For SG-1 a high average sediment accumulation rate (SAR) of 35.1 cm/kyr is determined with two maximum SAR intervals between 2.6-2.2 Ma and after 0.8 Ma indicating two episodic erosional events, which we relate to pulse tectonic uplift of the NE Tibetan Plateau with subsequent global cooling. Using spectral characteristics of magnetic susceptibility within sliding windows allows refining changes of SAR along the core SG-1. Both cores comprise mostly fine grained sediments (mudstone, clay, sandy clay) and in SG-1 frequent salt layers occur in the upper part. A trend of increasing aridification is observed in SG-1, with nearly twenty dry stages since ca. 1 Ma detected by evaporite minerals and extreme aridification from ca. 0.5 to 0.3 Ma onwards. These trends and stepwise drying events are supported by an increasing mean grain size towards younger ages. Palynofloras in SG-1 show an excellent degree of preservation. They can be attributed to two main biomes representing (i) mixed coniferous forests and woodlands that grew in the mountains surrounding the Qaidam basin, and (ii) a grass-steppe-like environment likely to be attributed to the basin itself. The long-term fluctuations of these main biomes allow insights into the monsoon dynamics of the Qaidam region, with a weakening of the East Asian summer monsoon and a strengthening of the winter monsoon during the past 2.8 Ma. A first set of high-resolution data provides insights into the climate variability during Marine Isotope Stage (MIS) 19

  11. Ordovician platform, slope, and basin facies in subsurface of southern North America

    SciTech Connect

    Alberstadt, L.P.; Colvin, G.; Sauve, J.

    1986-05-01

    Ordovician carbonates of the Nashville dome and Ozark dome regions have long been considered typical shelf deposits. In the subsurface to the south, in the Black Warrior basin, Mississippi Embayment, and Arkoma basin, these shelf carbonate units changed facies. The most significant change is the occurrence of a thick limestone unit characterized by a faunal and floral assemblage of Nuia, Girvanella (isolated long strands), Sphaerocodium, a delicate stacked-chambered organism (.algal), and sponge spicules and sponge mudstone clumps. In ascending order, the complete Ordovician sequence consists of: a lower dolostone, the Nuia-sponge limestone, a dolostone, and a limestone. The upper part of this four-fold sequence changes character westward into the Arkoma basin. The lower two units maintain their character for long distances along depositional strike and occur in parts of the Appalachians as far north as Newfoundland, and on the opposite side of the continent in Nevada. The Nuia-sponge assemblage is a distinctive petrographic marker and seems to be a persistent Ordovician rock and fossil assemblage of widespread occurrence. In Nevada, it occurs on the surface where it is associated with slump and slide features that suggest that it is an outer shelf or upper slope deposit. Coeval carbonates in the Ouachita Mountains are different and show indications of being deep water (basinal). Biostratigraphic evidence indicates that the succession in the subsurface is continuous; the regional Lower Ordovician-Middle Ordovician unconformity is absent. The Lower Ordovician-Middle Ordovician boundary falls near the top of the Nuia-sponge mudstone unit and not at the top of the underlying thick dolostone unit.

  12. Diagenesis of upper Devonian platform deposits in Emanual Range, Canning basin, western Australia

    SciTech Connect

    Pedone, V.A.; Meyers, W.J.

    1988-02-01

    The Emanuel Range consists of 600 m of peritidal and subtidal carbonate platform deposits of the Pillara Limestone (Givetian-lower Frasnian). Diagenesis of the lower 75 m contrasts markedly with the upper 520 m, principally in the occurrence of extensive dolomite. Formation of extensive secondary porosity by tectonic fracturing, in-situ brecciation, and dissolution of calcitic fossils was enhanced in previously dolomitized strata, exhibiting only minor occurrences in nondolomitized rocks. Formation of secondary porosity occurred over an extended period, marked by a succession of calcite cements, generally following a sequence from slightly ferroan, luminescently zoned cements to nonferroan, nonluminescent cement. Beckite chalcedony and hematite/goethite postdate but are associated with the final calcite cement. The post-dolomite diagenetic sequence suggests initial cementation under reducing burial conditions to final cementation under strongly oxidizing conditions. Fluids moving through the extensive Late carboniferous karst system in the platform may be the diagenetic agent for the later calcites, chalcedony, and iron oxides.

  13. A history of basin inversion, scarp retreat and shallow denudation: The Araripe basin as a keystone for understanding long-term landscape evolution in NE Brazil

    NASA Astrophysics Data System (ADS)

    Peulvast, Jean-Pierre; Bétard, François

    2015-03-01

    At the border between the states of Ceará and Pernambuco (northeast Brazil), the Chapada do Araripe is a high plateau (800-1000 m a.s.l.) formed by a slab of Cenomanian fluvial sandstone. This caprock is underlain by lacustrine or marine Albian layers and older rift deposits. During the Cretaceous, the Araripe basin lay at a palaeoelevation close to sea-level. Through a presentation and discussion of original field and cartographic data we analyse the mechanisms of topographic inversion in this sedimentary basin in relation to local or regional crustal upwarp. The contrast between the plateau - a weakly dissected structural surface - and the surrounding lowlands is explained through a study of the erosional scarps - cuesta-like landforms and their outliers - that fringe the Chapada. No evidence of local tectonic inversion is found. River incision, spring sapping, landslides and other forms of mass movement are listed as efficient processes of topographic inversion and scarp retreat, the rates and patterns of which appear to be controlled by lithological contrasts and conditions of exhumation of the basement. Geometric relationships with regional stepped surfaces (e.g., the low-elevation Sertaneja Surface), exhumed palaeosurfaces and regional drainage systems are analysed. Our estimation of the amplitude of denudation and topographic inversion (0.6-0.7 km) differs significantly from apatite fission-track-derived estimates reported in recent literature, which would imply burial by considerable thicknesses of younger sediments followed by 1.5 km or more of post-rift denudation - not just in the study area, but also in the Tucano-Jatoba basin to the south. The exhumation and reworking of surrounding basement surfaces probably began during the early Cenozoic, as shown to the northwest of the Chapada by the presence of widespread laterites of probable Palaeogene age. A second stage of topographic inversion occurred during the Oligocene or later. This would correspond to

  14. New occurrences of fossilized feathers: systematics and taphonomy of the Santana Formation of the Araripe Basin (Cretaceous), NE, Brazil

    PubMed Central

    Anelli, Luiz Eduardo; Petri, Setembrino; Romero, Guilherme Raffaeli

    2016-01-01

    Here we describe three fossil feathers from the Early Cretaceous Santana Formation of the Araripe Basin, Brazil. Feathers are the most complex multiform vertebrate integuments; they perform different functions, occurring in both avian and non-avian dinosaurs. Despite their rarity, fossil feathers have been found across the world. Most of the Brazilian feather fossil record comes from the Santana Formation. This formation is composed of two members: Crato (lake) and Romualdo (lagoon); both of which are predominantly reduced deposits, precluding bottom dwelling organisms, resulting in exceptional preservation of the fossils. Despite arid and hot conditions during the Cretaceous, life teemed in the adjacency of this paleolake. Feathered non-avian dinosaurs have not yet been described from the Crato Member, even though there are suggestions of their presence in nearby basins. Our description of the three feathers from the Crato laminated limestone reveals that, despite the small sample size, they can be referred to coelurosaurian theropods. Moreover, based on comparisons with extant feather morphotypes they can be identified as one contour feather and two downy feathers. Despite their rareness and low taxonomic potential, fossilized feathers can offer insights about the paleobiology of its owners and the paleoecology of the Araripe Basin. PMID:27441102

  15. New occurrences of fossilized feathers: systematics and taphonomy of the Santana Formation of the Araripe Basin (Cretaceous), NE, Brazil.

    PubMed

    Prado, Gustavo M E M; Anelli, Luiz Eduardo; Petri, Setembrino; Romero, Guilherme Raffaeli

    2016-01-01

    Here we describe three fossil feathers from the Early Cretaceous Santana Formation of the Araripe Basin, Brazil. Feathers are the most complex multiform vertebrate integuments; they perform different functions, occurring in both avian and non-avian dinosaurs. Despite their rarity, fossil feathers have been found across the world. Most of the Brazilian feather fossil record comes from the Santana Formation. This formation is composed of two members: Crato (lake) and Romualdo (lagoon); both of which are predominantly reduced deposits, precluding bottom dwelling organisms, resulting in exceptional preservation of the fossils. Despite arid and hot conditions during the Cretaceous, life teemed in the adjacency of this paleolake. Feathered non-avian dinosaurs have not yet been described from the Crato Member, even though there are suggestions of their presence in nearby basins. Our description of the three feathers from the Crato laminated limestone reveals that, despite the small sample size, they can be referred to coelurosaurian theropods. Moreover, based on comparisons with extant feather morphotypes they can be identified as one contour feather and two downy feathers. Despite their rareness and low taxonomic potential, fossilized feathers can offer insights about the paleobiology of its owners and the paleoecology of the Araripe Basin. PMID:27441102

  16. Boninite Volcanism in the Back-Arc: Testing Tectonic and Magmatic Controls at the NE Lau Basin Mata Seamounts

    NASA Astrophysics Data System (ADS)

    Glancy, S.; Rubin, K. H.; Hellebrand, E.; Embley, R. W.

    2012-12-01

    The North East Lau Basin is an actively spreading back-arc basin that has erupted a variety of igneous products. These include a series of young seamounts in the northeast of the basin called the Matas, which lay between the transform boundary marking the northern edge of the basin, the Tofua arc to the east, and the northeast Lau spreading center to the west. Sampling so far indicates that all are constructed of boninite pillow lavas except for one seamount which is composed of meimechite; nearly all are high Mg orthopyroxene-clinopyroxene-olivine porphorytic, with somewhat differentiated glass compositions relative to the whole rocks. The Mata volcanoes are geologically young (an eruption was observed at West Mata Volcano in May 2009 (Resing et al., Nat. Geosci, 4, 2011) and several of the northern Mata group have active hydrothermal systems), providing unique opportunities for insights into boninite formation. The Mata seamounts are in a unique setting, very close to the arc, but within the backarc region. The small, possibly monogenetic cones have formed in a small extensional basin along en-echelon fractures trending obliquely away from the subduction trench (Rubin and Embley 2012, AGU meeting). This pattern is in contrast to the arc-parallel lineated northeast Lau spreading center that intersects the E-W arm of the trench within ~25 km west of the Mata basin. We test two possible models for formation of the Matas using geochemical signatures within the lavas. In the first model, volcanism is sourced in part by fluids derived from the actively subducting slab, causing geochemical signatures related to the nearby active arc that decrease with distance from the arc. This model predicts that subduction related geochemical signatures would be greatest in the South where the volcanoes are closer to the downgoing slab. In an alternate model, volcanism is fed by extension-driven upwelling of back-arc mantle, which was enhanced by subduction-derived fluids at some

  17. Evidence for Thin Oceanic Crust on the Extinct Aegir Ridge, Norwegian Basin, N.E. Atlantic Derived from Satellite Gravity Inversion

    NASA Astrophysics Data System (ADS)

    Greenhalgh, E. E.; Kusznir, N. J.

    2006-12-01

    Satellite gravity inversion incorporating a lithosphere thermal gravity correction has been used to map crustal thickness and lithosphere thinning factor for the N.E. Atlantic. The inversion of gravity data to determine crustal thickness incorporates a lithosphere thermal gravity anomaly correction for both oceanic and continental margin lithosphere. Predicted crustal thicknesses in the Norwegian Basin are between 7 and 4 km on the extinct Aegir oceanic ridge which ceased sea-floor spreading in the Oligocene. Crustal thickness estimates do not include a correction for sediment thickness and are upper bounds. Crustal thicknesses determined by gravity inversion for the Aegir Ridge are consistent with recent estimates derived using refraction seismology by Breivik et al. (2006). Failure to incorporate a lithosphere thermal gravity anomaly correction produces an over-estimate of crustal thickness. Oceanic crustal thicknesses within the Norwegian Basin are predicted by the gravity inversion to increase to 9-10 km eastwards towards the Norwegian (Moere) and westwards towards the Jan Mayen micro-continent, consistent with volcanic margin continental breakup at the end of the Palaeocene. The observation (from gravity inversion and seismic refraction studies) of thin oceanic crust produced by the Aegir ocean ridge in the Oligocene has implications for the temporal evolution of asthenosphere temperature under the N.E. Atlantic during the Tertiary. Thin Oligocene oceanic crust may imply cool (normal) asthenosphere temperatures during the Oligocene in contrast to elevated asthenosphere temperatures in the Palaeocene and Miocene-Recent as indicated by volcanic margin formation and the formation of Iceland respectively. Gravity inversion also predicts a region of thin oceanic crust to the west of the northern part of the Jan Mayen micro-continent and to the east of the thicker oceanic crust currently being formed at the Kolbeinsey Ridge. Thicker crust (c.f. ocean basins) is

  18. Stone Age settlement and Holocene water level changes of the Baltic Sea in the Torvajoe Basin area, Narva-Luga Klint Bay, NE Estonia

    NASA Astrophysics Data System (ADS)

    Raig, Hanna; Rosentau, Alar; Muru, Merle; Risberg, Jan

    2014-05-01

    The Tõrvajõe basin is located in NE Estonia in the southern part of the Narva-Luga Klint Bay, that is characterized by slow post-glacial isostatic uplift (about 0-1mm/yr) and slowly undulating low topography. Post-glacial changes of the water-level of the Baltic Sea have at times flooded the area, and at times, it has emerged as terrestrial land. In addition to a complex geological development, the surroundings of the Tõrvajõe basin are interesting from the archaeological point of view because of abundant archaeological findings in the area, of which the oldest (c 8.1 cal ka BP) from the Mesolithic period and the majority, indicating very intense habitation (c 7.1-5.5 cal ka BP), from the Neolithic period. Development of the Tőrvajőe basin area during the period of Stone Age settlement (c 8.1-5.5 cal. ka BP) is studied with multiple geological and archaeological proxies. Sediments are described by lithostratigraphical methods, loss-on-ignition. AMS radiocarbon dates are used to date events and create an age-depth model. Environment is described by pollen analyses and water environment by siliceous microfossil analyses. Palaeogeographical reconstructions for time slices of interest are created to illustrate Stone Age settlement pattern and changes of the coastline and landscape over time. The aim of this interdisciplinary study is to investigate and associate palaeoenvironmental conditions and water-level changes with Stone Age settlement pattern in the Tőrvajőe area. Results show four developmental stages in the post-glacial history of the basin: Ancylus Lake lagoon, mire, lagoon during the Litorina Sea and mire. During the Ancylus Lake transgression at about 10.8-10.2 cal. ka BP a spit started to form north of the basin and a lagoon evolved behind it. Following the Ancylus Lake regression river activity and formation of palaeosoil and fen peat took place. Due to the Litorina Sea transgression, that was initially slower but accelerated around 7.8-7.6 cal ka

  19. Infrared inspection applied to offshore platforms: Petrobras experience at Campos Basin

    NASA Astrophysics Data System (ADS)

    Verdini, Edson A.; Veratti, Attilio B.

    2002-03-01

    Bacia de Campos (Rio de Janeiro - Brazil) is one of the biggest offshore petroleum fields in the world today. In June 2001, Bacia de Campos, having more than 490 oil wells, 34 offshore platforms and 7 modified ships in operation, reached 1,3 million barrels/day. If compared to OPEP countries only nine of them got an average production higher than 1 million barrels/day in 2000, which means it can be placed on the 10th position in the rank of oil producers. In this context this work aims not only to show the results achieved within the introduction of thermographic inspections in offshore oil production (platforms and ships), but also the financial results (ROI - Return of Investment) considering the use of this particular technique. Bacia de Campos got a ROI around 7 million dollars in the last 4 years, which means a hundred times higher than the total cost of thermographic services in the same period. As far as we know this is one of the best results already reported in the world. We also present the methodology applied to analyze thermal anomalies in electrical components and data management software, including advanced Digital Reports sent via Internet.

  20. Organic geochemical characterisation of shallow marine Cretaceous formations from Yola Sub-basin, Northern Benue Trough, NE Nigeria

    NASA Astrophysics Data System (ADS)

    Sarki Yandoka, Babangida M.; Abdullah, Wan Hasiah; Abubakar, M. B.; Hakimi, Mohammed Hail; Jauro, Aliyu; Adegoke, Adebanji Kayode

    2016-05-01

    The shallow marine shales of the Cretaceous formations namely Yolde, Dukul, Jessu, Sekuliye and Numanha ranging in age from Cenomanian to Coniacian within the Yola Sub-basin in the Northern Benue Trough, northeastern Nigeria were analysed to provide an overview on their hydrocarbon generation potential. This study is based on pyrolysis analysis, total organic carbon content (TOC), extractable organic matter (EOM), biomarker distributions and measured vitrinite reflectance. The present-day TOC contents range between 0.24 and 0.71 wt. % and Hydrogen Index (HI) values between 8.7 and 113 mg HC/g TOC with Type III/IV kerogens. Based on the present-day kerogen typing, the shale sediments are expected to generate mainly gas. Biomarker compositions indicates deposition in a marine environment under suboxic conditions with prevalent contribution of aquatic organic matter and a significant amount of terrigenous organic matter input. Organic matter that is dominated by marine components contains kerogens of Type II and Type II-III. This study shows that the organic matter has been affected by volcanic intrusion and consequently, have reached post-mature stage of oil generation. These higher thermal maturities levels are consistent with the vitrinite reflectance ranging from 0.85 to 2.35 Ro % and high Tmax (440-508 °C) values as supported by biomarker maturity ratios. Based on this study, a high prospect for major gas and minor oil generation potential is anticipated from the shallow marine Cretaceous formations from Yola Sub-basin.

  1. Emission factor estimation of ca. 160 emerging organic microcontaminants by inverse modeling in a Mediterranean river basin (Llobregat, NE Spain).

    PubMed

    Banjac, Zoran; Ginebreda, Antoni; Kuzmanovic, Maja; Marcé, Rafael; Nadal, Martí; Riera, Josep M; Barceló, Damià

    2015-07-01

    Starting from measured river concentrations, emission factors of 158 organic compounds out of 199 analyzed belonging to different groups of priority and emerging contaminants [pesticides (25), pharmaceuticals and hormones (81), perfluoroalkyl substances (PFASs) (18), industrial compounds (12), drugs of abuse (8) and personal care products (14)] have been estimated by inverse modeling. The Llobregat river was taken as case study representative of Mediterranean rivers. Industrial compounds and pharmaceuticals are the dominant groups (range of 10(4) mg·1000 inhab(-1)·d(-1)). Personal care products, pesticides, PFASs and illegal drugs showed a load approximately one order of magnitude smaller. Considered on a single compound basis industrial compounds still dominate (range of ca. 10(3) mg·1000 inhab(-1)·d(-1)) over other classes. Generally, the results are within the range when compared to previously published estimations for other river basins. River attenuation expressed as the percentage fraction of microcontaminants eliminated was quantified. On average they were around 60-70% of the amount discharged for all classes, except for PFASs, that are poorly eliminated (ca. 20% on average). Uncertainties associated with the calculated emissions have been estimated by Monte-Carlo methods (15,000 runs) and typically show coefficients of variation of ca. 120%. Sensitivities associated with the various variables involved in the calculations (river discharge, river length, concentration, elimination constant, hydraulic travel time and river velocity) have been assessed as well. For the intervals chosen for the different variables, all show sensitivities exceeding unity (1.14 to 3.43), tending to amplify the variation of the emission. River velocity and basin length showed the highest sensitivity value. Even considering the limitations of the approach used, inverse modeling can provide a useful tool for management purposes facilitating the quantification of release rates of

  2. Analysis of the occurrence and risk assessment of polar pesticides in the Llobregat River Basin (NE Spain).

    PubMed

    Köck-Schulmeyer, Marianne; Ginebreda, Antoni; González, Susana; Cortina, Jose Luis; de Alda, Miren López; Barceló, Damià

    2012-01-01

    Contamination of surface waters by pesticides continues to be the focus of concern for water authorities due to the growing evidence of their deleterious effects on aquatic life. In this context, the present work investigates the occurrence of 16 selected pesticides belonging to the classes of triazines, phenylureas, organophosphates, chloroacetanilides and thiocarbamates in surface waters from the Llobregat River (NE Spain) and some of its tributaries (Anoia and Rubí) and assesses their potential impact on the aquatic organisms by applying a recently developed index, the Short-term Pesticide Risk Index for the Surface Water System (PRISW-1), which takes into account the pesticides concentrations and their overall toxicity against three aquatic organisms (algae, Daphnia, and fish). Chemical analysis, performed by means of a fully automated method based on isotope dilution on-line solid phase extraction-liquid chromatography-electrospray-tandem mass spectrometry (on-line SPE-LC-ESI-MS/MS), revealed diuron and diazinon as the most ubiquitous and abundant compounds with levels up to 818 and 132 ng L(-1), respectively. Total pesticide concentrations, which in only 1 out of 66 samples surpassed 500 ng L(-1), were higher in the tributaries than in the river but their contribution in terms of mass-loads to the overall pesticide pollution of the Llobregat River was relatively small. Contamination increased downstream of the river and was clearly influenced by rainfall and hence river flow. Application of the PRISW-1 index indicated that, although pesticides levels fulfilled the European Union Environmental Quality Standards (EQS) for surface waters, the existing pesticide contamination poses a low to high ecotoxicological risk for aquatic organisms, that algae and macro-invertebrates are at higher risk than fish, and that the organophosphates diazinon and malathion and the phenylurea diuron are the major contributors to the overall toxicity and therefore the most

  3. Genetic sequence relationships of Winnipegosis platform carbonates, southern Elk Point basin, North Dakota

    SciTech Connect

    Shanley, K.W.; Cross, T.A.

    1988-01-01

    Examination of cores and well log data from the Winnipegosis Formation (Givetian) within a study area of approximately 11,500 mi/sup 2/ (30,000 km/sup 2/) in northern North Dakota allows recognition of seven time-stratigraphic progradational units within the Winnipegosis Formation. Together with the underlying Ashern Formation, these units are arranged in landward-stepping, vertical stacking, and seaward-stepping geometric patterns, which reflect changes in relative sea level. Abrupt juxtaposition of shallow over deeper water lithologies, evidence for subaerial exposure, and onlap geometries further suggest that these progradational units form two larger, Vail-type sequences separated by regionally persistent unconformities or their correlative conformities. Sea level rise during the early Eifelian caused southeastward onlap of the Ashern Formation onto Middle Silurian carbonates of the Interlake Formation. Maximum flooding, expressed by deepest marine facies and a hardground surface, suggests the existence of a condensed section at the top of the Ashern Formation. This was developed during the maximum rate of sea level rise. A decrease in the rate of sea level rise resulted in aggradation of lower Winnipegosis units on a gently dipping ramp. These are represented by nodular and burrowed open marine limestones with scattered stromatoporoid patch reefs and grainstone shoals. During the subsequent sea level fall, represented by Temple units, a shelf margin with pronounced depositional topography and adjacent starved basin were developed. Temple strata include coral-brachiopod-stromatoporoid reefs and productive fore-reef talus deposits along the shelf margin rim.

  4. Fast Deposition of Small River Particles on the NE South China Sea Slope Basin Since the Last Glacial Maximum

    NASA Astrophysics Data System (ADS)

    Lin, S.; Cheng, W. Y.; Hsieh, I. C.

    2015-12-01

    Huge quantities of small rivers derived suspended particles are exporting to the ocean from oceanic islands at the present time. Depending on location and proportion of shelf/slope area, a major fraction of small river particles may by-pass the shelf region, transport and deposit on the deep ocean basin. Major mechanisms driving those huge quantities of small river derived particles to the ocean are quantity of precipitation from monsoon and those from short period of tropical cyclone. Although data demonstrate that deeper part of the South China Sea, SCS, is the major final burial location of the river derived particles from the island of Taiwan, it is not sure if this was the same during the glaciation when monsoon and climatic conditions were drastic different from the present time. The purpose of this study is to understand history of small river derived sediment export and deposition during climatic change. A long piston core with length of ~35 meter was taken on r/v Marion DuFresne on a slope basin offshore SW Taiwan. We have measured density, magnetic susceptibility with multi-sensor core logger, MSCL, and organic, inorganic carbon, C/N ratio, biogenic silica as well as grain sizes. Foraminifera (Orbulina universa, Globigerinoides sacculifer and Globigerinoides conglobatus) were picked and measured carbon 14 for age determination. Two different types of processes control sediment deposition in our study site, steady state and event driven sedimentation. Our results demonstrated that sedimentation rates were consistent during each major periods, the Holocene (present to 10k year) and the transition (10-20 k year) period, but, difference existed in between the two. Sedimentation rate was about twice faster during the transition period (20-10k year) than that at the Holocene (10-present time) at our study site. A number of spikes existed in our study site, probably a result of turbidite overflow from the adjacent canyon. Frequency and total thickness of event

  5. Model quantification of the CO2 storage in the Los Páramos site (Duero basin, NE Spain)

    NASA Astrophysics Data System (ADS)

    Nardi, Albert; Grandia, Fidel; Abarca, Elena; Motis, Kilian; Molinero, Jorge

    2013-04-01

    The Duero basin in NW Spain is one the most promising basin for CO2 storage in the Iberian Peninsula due to the existence of favourable deep aquifers close to large CO2 emission point sources. A number of projects are presently active either for scientific research (e.g., the Hontomín site, OXI-CFB300 EPRR project) or commercial purposes (e.g., Sahagún and Los Páramos projects). The project called Los Páramos intends to assess the injection of CO2 in a group of dome-shaped structures with an estimated total capacity of 200 Mt (ranked 2nd in the Iberian Peninsula, IGME 2010). These domes were studied in the past for hydrocarbon exploration and a large body of information is available from seismic profiles (over 170 km) and 3 deep wells. The Los Páramos site is emplaced in the San Pedro Folded Band (SPFB) that consists mainly of thick-skinned thrusts of Mesozoic rocks (Triassic and Upper Cretaceous) sealed by a thick (1200-1500 m), undeformed cover of Tertiary claystones. Dome-like structures are related to thrusts leading to favourable reservoirs. The target horizon for CO2 storage is the Utrillas Fm sandstone with high porosity (13-20%) and thickness (225-250 m). In three of the domes, the Utrillas Fm is below -800m, allowing thus the storage of CO2(sc). This sandstone hosts an aquifer containing saline water, up to 50 g·L-1, according to the data from drill wells. The presence of saline groundwater is explained by water interaction with Triassic evaporite layers just underlying the Utrillas Fm sandstones. The CO2 storage at Los Paramos site is planned via injection of supercritical CO2 (CO2(sc)) in the Utrillas Fm. In general, the next four trapping mechanisms are expected, which are of increasing importance through time (1) structural, (2) residual saturation, (3) dissolution, and (4) mineral. The prediction of the mass of CO2 stored through time in any storage systems is an essential parameter in the pre-injection assessment of a geological storage. For

  6. Isotope evidence of palaeorecharge and palaeoclimate in the deep confined aquifers of the Chad Basin, NE Nigeria.

    PubMed

    Maduabuchi, Chris; Faye, Serigne; Maloszewski, Piotr

    2006-11-01

    Groundwaters from the Quaternary and Continental Terminal Formations in the Nigeria sector of the Chad Sedimentary Basin (CSB) together with rain and surface waters have been chemically and isotopically analyzed in order to investigate sources and ages of waters, possible modern renewal and mixing of the deep groundwaters, and to infer palaeoclimate incidences. Most of the waters are slightly to moderately mineralized and are of Na-HCO(3) type induced mainly by Na-feldspar weathering and ion exchange reactions. The wide range of the delta(18)O and delta(2)H values and (3)H contents in the upper aquifer indicate replenishment with modern meteoric water. However, the deep system (middle and lower aquifers) with a narrow range of depleted stable isotope values and low (14)C activities indicates that these waters have a palaeometeoric origin. The period of infiltration was within the humid and cooler period (35 to 40 ka BP) prior to the Last Glacial Maximum. In addition, the isotope compositions of the deep system show no mixing with modern waters. These results are in agreement with other palaeorecord studies in the Sahel zone during this period. PMID:16989892

  7. 40Ar/ 39Ar ages and Sr-Nd-Pb-Os geochemistry of CAMP tholeiites from Western Maranhão basin (NE Brazil)

    NASA Astrophysics Data System (ADS)

    Merle, Renaud; Marzoli, Andrea; Bertrand, Hervé; Reisberg, Laurie; Verati, Chrystèle; Zimmermann, Catherine; Chiaradia, Massimo; Bellieni, Giuliano; Ernesto, Marcia

    2011-03-01

    The Central Atlantic Magmatic Province (CAMP), emplaced at the Triassic-Jurassic (T-J) boundary (~ 200 Ma), is among the largest igneous provinces on Earth. The Maranhão basin in NE Brazil is located around 700 km inland and 2000 km from the site of the earliest Pangea disruption. The CAMP tholeiites occur only in the western part of the basin and have been described as low and high-Ti. Here we document the occurrence of two sub-groups among the high-Ti tholeiites in the Western Maranhão basin. The major and trace elements and the Sr-Nd-Pb isotopic ratios define three chemical groups corresponding to the low-Ti (TiO 2 < 1.3 wt.%), high-Ti (TiO 2 ~ 2.0 wt.%) and evolved high-Ti (TiO 2 > 3 wt.%) western Maranhão basin tholeiites (WMBT). The new 40Ar/ 39Ar plateau ages obtained on plagioclase separates for high-Ti (199.7 ± 2.4 Ma) and evolved high-Ti WMBT (197.2 ± 0.5 Ma and 198.2 ± 0.6 Ma) are indistinguishable and identical to those of previously analyzed low-Ti WMBT (198.5 ± 0.8 Ma) and to the mean 40Ar/ 39Ar age of the CAMP (199 ± 2.4 Ma). We also present the first Re-Os isotopic data for CAMP basalts. The low and high-Ti samples display mantle-like initial ( 187Os/ 188Os) i ranging from 0.1267 to 0.1299, while the evolved high-Ti samples are more radiogenic (( 187Os/ 188Os) i up to 0.184) We propose that the high-Ti WMBT were derived from the sub-lithospheric asthenosphere, and contaminated during ascent by interaction with the subcontinental lithospheric mantle (SCLM). The evolved high-Ti WMBT were derived from the same asthenospheric source but experienced crustal contamination. The chemical characteristics of the low-Ti group can be explained by partial melting of the most fertile portions of the SCLM metasomatized during paleo-subduction. Alternatively, the low-Ti WMBT could be derived from the sub-lithospheric asthenosphere but the resulting melts may have undergone contamination by the SCLM. The occurrences of high-Ti basalts are apparently not

  8. A Satellite Driven Real-time Forecasting Platform in the Upper Zambezi Basin: A Multi-model Comparison

    NASA Astrophysics Data System (ADS)

    Valdes, J. B.; Wi, S.; Serrat-Capdevila, A.; Demaria, E. M.; Durcik, M.

    2015-12-01

    In large basins such as the Upper Zambezi where concentration times are of many days or even weeks, satellite precipitation products available in real-time become a key component enabling - with the use of hydrologic models - streamflow forecasts for downstream locations with enough lead time to inform decision-making. We present a real-time streamflow forecasting application based on this concept, using the TMPA and CMORPH rainfall products (which we bias-correct using the CHIRPS product) to force four distributed hydrologic models (VIC, HyMod, HBV, Sacramento) covering a variety of levels of model complexity. This study aims at establishing a multi-model satellite-based streamflow forecasting platform as a tool that can inform water management in real-time. This work is part of the efforts of the SERVIR Applied Sciences Team to bring NASA Earth Observation Applications into decision support tools for managing water resources in the Upper Zambezi, in collaboration with the Southern African Development Community Climate Services Center and the Zambezi Watercourse Commission.

  9. The Quaternary Tahoe-Medicine Lake trough: The western margin of the Basin and Range transition, NE California

    SciTech Connect

    Page, W.D. . Geoscience Dept.); Sawyer, T.L. ); Mclaren, M.K.; Savage, W.U.; Wakabayashi, J.

    1993-04-01

    The Tahoe-Medicine Lake trough is a series of small right-stepping, en echelon tectonic depressions that extend 400 km NNW from Lake Tahoe to near the Oregon border. The trough developed since the Miocene, and forms the eastern edge of the Sierra Nevada and southern Cascade Mountains, and the western boundary of the Plumas province and Modoc Plateau, which are transitional to the Basin and Range. The geomorphic expression of the trough indicates late Pleistocene and Holocene fault activity along its length. The continuity of the structure, however, has been masked in places by volcanic deposits that have filled or partly filled the tectonic lows. Moderate historical earthquakes (M5-6) have occurred only along the southern trough. Microearthquakes prominently follow the trough from Lake Tahoe north [omega] Lake Almanor. From there northward, seismicity patterns are predominantly shallow (<5 km) volcanic-related clusters at Mt. Lassen, Medicine Lake, and Tennent and Stephens passes. Geologic and seismicity data indicate that the NW-trending south-central section has a significant component of right-slip, which appears to be related to the Walker Lane shear zone. To the south, the trough is the NNW-striking, 10- to 20-km-wide Tahoe depression, which extends from Lake Tahoe to the Sierra Valley and is partly filled with Quaternary volcanic deposits near Truckee. The escarpment and probable displaced moraines along this section indicate late Pleistocene and possibly Holocene activity. Seismicity is diffuse except in the vicinity of the 1966 Truckee earthquake (M6.0). Northward, from Sierra Valley to American Valley, the trough changes trend to the NW, and is the 6-km-wide Plumas trench, which down-faults the Mehrten Fm. (Miocene to early Pliocene) about 1,000 m.

  10. Lithofacies and sequence stratigraphic analysis of the Upper Jurassic siliciclastics in the eastern Kopet-Dagh Basin, NE Iran

    NASA Astrophysics Data System (ADS)

    Zand-Moghadam, Hamed; Moussavi-Harami, Reza; Mahboubi, Asadollah; Aghaei, Ali

    2016-05-01

    The Upper Jurassic (Oxfordian-Kimmeridgian) Mozduran Formation is the most important gas reservoirs of the northeast Iran. Siliciclastic facies of this formation in eastern most parts of the basin have not been studied yet. Therefore, four stratigraphic sections of Mozduran Formation have been selected in the Kole-Malekabad, Kale-Karab, Deraz-Ab and Karizak to interpret depositional history and analyze depositional sequences. Based on texture and sedimentary structures, 14 slilciclastic lithofacies were identified and classified into four categories, including conglomerate (Gms, Gp, Gt), sandstone (Sh, Sp, St, Sr, Sl, Sm, Se), mud rock (Fl) and intermediate sandstone-mud rock (Sr (Fl), Sr/Fl, Fl (Sr)). Identified lithofacies formed four architectural elements CH, SB, LA and FF. Lithofacies characteristics and architectural elements with mostly bimodal pattern of paleocurrents show that the majority of Mozduran lithofacies deposited in the coastal environment (tidal influence). Sequence stratigraphic analysis shows that the Kole-Malekabad section consists of two depositional sequences while other sections are characterized by three depositional sequences. The lower and upper sequence boundaries of the Mozduran Formation in all stratigraphic sections are SB1 that are distinguished by paleosol and sometime conglomerate horizons. Most of depositional sequences in studied sections are composed only of TST and HST. The TST deposits consist mostly of quartzarenite and litharenite petrofacies that have been deposited in the tidal zone. HST packages are mostly including mud rocks with interdeds of sandstone lithofacies that are deposited in supratidal setting. The LST facies is recognized only in the DS3 (equivalent to the second depositional sequences of the Kole-Malekabad), which consist of conglomerate facies. Instead, the Kole-Malekabad section is often composed of supratidal gypsiferrous shales, indicating sea level fall in the study area.

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

    NASA Astrophysics Data System (ADS)

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

    2016-08-01

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

  12. Comment on "Chronology of the Early Toarcian environmental crisis in the Lorraine Sub-Basin (NE Paris Basin)" by W. Ruebsam, P. Münzberger, and L. Schwark [Earth and Planetary Science Letters 404 (2014) 273-282

    NASA Astrophysics Data System (ADS)

    Boulila, Slah; Hinnov, Linda A.

    2015-04-01

    Ruebsam et al. (2014), henceforth "Ruebsam et al.", recently conducted a cyclostratigraphic study of an Early Toarcian interval from the FR-210-078 drill-core, located in the Lorraine Sub-Basin (NE Paris Basin). The goal was to assess the durations of ammonite zones and the carbon isotope excursion (CIE) of the T-OAE. They used magnetic susceptibility and sediment color as paleoclimatic proxies to seek evidence for Milankovitch cycles. Although the mean sedimentation rate of the Early Toarcian in the Lorraine FR-210-078 drill-core is reported as low (0.8 cm/kyr, see Section 2 below) compared to other equivalent sections used for cyclostratigraphy (1.4 cm/kyr at Sancerre, 2.5 cm/kyr at Yorkshire, 3.5 cm/kyr at Peniche, see Boulila et al., 2014, henceforth "Boulila et al."), Milankovitch-like cyclicities are well recorded in the color reflectance a* data (Figs. 1, 2). Ruebsam et al. compared their results and the inferred duration estimates with those of Boulila et al., suggesting significant differences in the durations of the CIE and in the occurrence of obliquity-dominant cycles. Here we comment on Ruebsam et al.'s interpretation and propose an alternative one, and discuss the implications of both interpretations on the duration of the CIE. Finally, we discuss the discrepancy in the hypothesis of obliquity forcing during the CIE as suggested by Boulila et al. versus after the CIE as postulated by Ruebsam et al.

  13. Flash flood frequency assessment from historical data in an ungauged basin: the Ondara River at Tàrrega (NE Spain)

    NASA Astrophysics Data System (ADS)

    Balasch, J. C.; Tuset, J.; Ruiz-Bellet, J. Ll.

    2010-09-01

    In the last four centuries, the Ondara River has flash-flooded several times the town of Tàrrega (NE Spain), resulting in a huge amount of deaths and damages to buildings. Indeed, from the early XVIIth Century, a minimum of six major events have occurred, in which the old-town streets have been flooded -in some cases, up to the dwellings’ second floor-, commonly during night hours, with an obvious surprise factor which added to the quickness of the events. These six events happened in 1644, 1783, 1842, 1874, 1930 and 1989; the flood marks preserved in Sant Agustí Street at Tàrrega allowed the reconstruction of the peak flows. The Ondara River catchment at Tàrrega has an area of 150 km2 and an average slope of 1,6%; there are neither gauging records nor hydraulic structures. In order to find a relationship between magnitude and frequency of the major flash floods, a two-staged methodology was used: in the first stage, the sediment-laden peak flow of each flood was calculated; in the second one, an extreme value distribution function was fitted to those peak flows in order to assess their recurrence likelihood. More in detail, each flash flood peak flow was reconstructed through the iterative application of a hydraulic model. The input data for each modelling were: i) a digital terrain model of the river bed; for each flood, the topographic and the land use changes given by contemporary maps and archaeological data were taken into account ii) the stream, floodplain and urban areas roughness coefficients (0.035, 0.04, and 0.1, respectively) iii) the channel slope (0.0045) iv) a tentative peak flow. As said above, the process was iterative, trying different peak flows until the modelled maximum water level was close enough to the one known through the flood limnimarks. The hydraulic model used was the unidimensional HEC-RAS v. 4.0/2008 (USACE), applied in several cross sections of the Ondara River at Tàrrega, spaced 40-50 m in average. Thence, the Bayliss & Reed

  14. A 7.3-1.6 Ma grain size record of interaction between anticline uplift and climate change in the western Qaidam Basin, NE Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Lu, Yin; Fang, Xiaomin; Appel, Erwin; Wang, Jiuyi; Herb, Christian; Han, Wenxia; Wu, Fuli; Song, Chunhui

    2015-04-01

    How sediment grain size corresponds to both climate change and tectonics is increasingly the focus of debate. The shrinkage and migration of the huge paleo-lake in the western Qaidam Basin (WQB), NE Tibetan Plateau (TP) provide an excellent case study. We present a nearly 6 Ma well-dated high-resolution grain size record from the 723-m-deep drill core SG-1b (located in the Jianshan Anticline in the WQB) to show how sediment grain size responds to anticline growth and climate change. The results show that variations in grain size represent three distinct phases. Phase I (7.3-3.6 Ma) is characterized by fine sediments with good sorting, with a predominance of clay and fine silt. During this phase, the drilling site was in a deep to semi-deep lake environment, the Jianshan Anticline has undergone relatively weak tectonics and the climate was dry, but still much wetter than that in the Quaternary; grain size variation and lacustrine deposition were principally controlled by climate. Phase II (~3.6-3.3 Ma) was a transitional period characterized by a rapid shift toward consistently coarser sediments with increased volumes of medium-coarse silt and sand. During this phase, the drilling site underwent a dramatic shift to a shallow lake environment, the anticline experienced rapid uplift and the climate was in an episode of rapid drying; grain size variation and lacustrine deposition were principally controlled by tectonics in the Jianshan Anticline. Phase III (~3.3-1.6 Ma) was a period exhibiting a long-term fining trend in mean grain size relative to Phase II, but still much coarser than that of Phase I, and with a distinct and prolonged increase in very fine sediments accompanied by poor sorting. During this phase, the drilling site was in a shallow lake environment between 3.3 Ma and 1.9 Ma, and finally became a lakeshore-like environment between 1.9 Ma and 1.6 Ma; the anticline experienced rapid and continuous uplift and the climate was in a long-term stepwise drying

  15. Accelerated subsidence and sedimentation in the Levant Basin during the Late Tertiary and concurrent uplift of the Arabian platform: Tectonic versus counteracting sedimentary loading effects

    NASA Astrophysics Data System (ADS)

    Bar, Oded; Gvirtzman, Zohar; Feinstein, Shimon; Zilberman, Ezra

    2013-06-01

    Since the Middle Eocene, the northwest Arabian Platform has been emerging from the water and rising above sea level, whereas the adjacent Levant Basin has been subsiding and accumulating a thick sedimentary section. This study investigates these opposing vertical motions and the relative roles of tectonic-driven versus isostatic adjustment forces involved. Such a distinction is strongly dependent on a reliable estimation of the paleobathymetry, which in pelagic environments may vary substantially. We use two different methods to estimate the paleo-water-depth in the deep Levant Basin in the Tertiary time. Isostatic balancing calculations with the adjacent inland region are employed to estimate the paleo-water-depth in the deep Levant Basin in the Middle Eocene, just before the commencement of the Late Tertiary tectonic phase. For later periods, we use morpho-structural elements such as abrasion surfaces and incised canyons to build laterally changing topo-bathymetry profiles. Our results indicate that in the Mid-Eocene water depth in the deep Levant Basin was 2-3.5 km, which gradually decreased to 1.5 km today. Based on these results, our analysis shows that the enhanced subsidence of the Levant Basin reflects an isostatic response to sedimentary filling of a pre-existing deep-water basin with no involvement of a downward tectonic force. On the contrary, we suggest that the regional tectonic force was upward, counteracting a sedimentary loading effect. Further regional implication of this understanding is that the cause for uplifting and exposure of the NW Arabian Platform in the Late Tertiary extended far westward beyond the inland region.

  16. Orbitally tuned age model for the late Pliocene-Pleistocene lacustrine succession of drill core SG-1 from the western Qaidam Basin (NE Tibetan Plateau)

    NASA Astrophysics Data System (ADS)

    Herb, Christian; Appel, Erwin; Voigt, Silke; Koutsodendris, Andreas; Pross, Jörg; Zhang, Weilin; Fang, Xiaomin

    2015-01-01

    The availability of accurate and reliable age control is a crucial prerequisite for palaeoclimate studies, particularly when different archives are to be compared. Here we present a detailed depth-to-time transformation for the lacustrine sediments of a ˜940-m-long drill core (SG-1) from the western Qaidam Basin (NE Tibetan Plateau). To establish a more precise age model than the one previously available, which was based solely on magnetostratigraphic dating using polarity boundaries as tie points, we applied time-series analysis on magnetic susceptibility (χ) variation. The χ data are available in high resolution and are considered to be closely linked to orbital forcing. Since the sediment accumulation rate (SAR) varies strongly throughout the succession of core SG-1, conventional cyclostratigraphy by bandpass filtering cannot be applied. We present two alternative age models based on spectral characteristics and orbital tuning. The first age model (TPspec) is based on the assumption that changes in SAR occurred when the frequency spectra revealed obviously different characteristics in the spectral pattern. For the second age model (SARA), SAR was adjusted every 2 m by comparing observed with expected orbital cycles in accordance with the age of magnetic reversals. This age model appears more robust and shows the most convincing spectral results in the frequency and wavelet power spectrum of χ. According to the SARA age model, SAR varies between 14 and 73 cm kyr-1, and the bottom of SG-1 has an age of 2.69 Ma. Our results show that orbital tuning can be successfully applied for sequences with strongly variable SAR. The age model SARA can be used for a more detailed analysis of the existing multiproxy data set in terms of palaeoclimate evolution. The most prominent feature of χ spectra using the SARA age model is the identification of the middle Pleistocene transition.

  17. Diversity and factors controlling widespread occurrence of syn-rift Ladinian microbialites in the western Tethys (Triassic Catalan Basin, NE Spain)

    NASA Astrophysics Data System (ADS)

    Mercedes-Martín, Ramon; Arenas, Concha; Salas, Ramon

    2014-11-01

    that thrombolites exhibit abundant botryoidal and isopachous fibrous marine cements, corrosion and significant microbial evidence allow us to hypothesize about the relationship between thrombolite occurrence and hydrothermal fault-controlled fluid circulation during the Triassic rifting. The two depositional models here proposed constitute a step forward the understanding of the platform-to-basin microbialite heterogeneity during the Ladinian. Furthermore this work sheds new light on the mechanisms that likely promoted microbialite development during a period of major ecological restructuration and complex oceanographic conditions.

  18. A Late Jurasssic to Cretaceous sedimentological and chemostratigraphic transect trough the Oman Mountains; from the Arabian Platform into the Hawasina Basin

    NASA Astrophysics Data System (ADS)

    Wohlwend, Stephan; Celestino, Ricardo; Rehakova, Daniela; Weissert, Helmut

    2014-05-01

    The Oman mountains preserve a Late Jurassic to Cretaceous continental margin transect with the Arabian carbonate shelf and the adjacent deep Hawasina Basin which is outcropping in the nappe pile of the Oman Mountains today. The whole nappe pile containing the continental margin transect is today outcropping in the Central Oman Mountains. The sediment successions of the Platform (Kahmah & Wasia Group) and the Hawasina Basin (Sumeini, Hamrat Duru and Kawr Group) provide the opportunity to investigate the response of an eastern Tethyan equatorial ocean system to multiple perturbations of the carbon cycle during the Cretaceous. Shallow water sediments on the Arabian carbonate shelf and continental slope to turbiditic basinal successions are difficult to date with biostratigraphy and sequence stratigraphy. Therefore we complement existing sequence and biostratigraphy with our newly established carbon isotope chemostratigraphy. The Hawasina Basin and also the easternmost Arabian Platform were affected by the Late Jurassic sea level rise, by changes in oceanography and also by regional tectonics. The widespread shift towards a "pelagic Maiolica Limestone Facies" (Lower Sid'r, Nadan Fm, Rayda Fm) documents this transition in oceanography. Chemo- and biostratigraphy serve for correlation of the pelagic facies across the Hawasina Basin. Pelagic to hemipelagic conditions existed until the time of the Valanginian carbon isotope excursion. With the onset of this excursion chert and silicification features in the pelagic sediments disappeared for a while. Coarse turbidites indicate that the Arabian carbonate platform prograded during Valaginian and Hauterivian time more than 300 km towards the northeast. Facies changes towards coarser turbidites complicates the use of chemostratigraphy as a correlation tool. However, chemostratigraphy of the Barremian to Cenomanian combined with existing radiolarian biostratigraphy in the Hamrat Duru Group shows episodes of reduced sedimentation

  19. The Huaihe Basin Water Resource and Water Quality Management Platform Implemented with a Spatio-Temporal Data Model

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Zhang, W.; Yan, C.

    2012-07-01

    Presently, planning and assessment in maintenance, renewal and decision-making for watershed hydrology, water resource management and water quality assessment are evolving toward complex, spatially explicit regional environmental assessments. These problems have to be addressed with object-oriented spatio-temporal data models that can restore, manage, query and visualize various historic and updated basic information concerning with watershed hydrology, water resource management and water quality as well as compute and evaluate the watershed environmental conditions so as to provide online forecasting to police-makers and relevant authorities for supporting decision-making. The extensive data requirements and the difficult task of building input parameter files, however, has long been an obstacle to use of such complex models timely and effectively by resource managers. Success depends on an integrated approach that brings together scientific, education and training advances made across many individual disciplines and modified to fit the needs of the individuals and groups who must write, implement, evaluate, and adjust their watershed management plans. The centre for Hydro-science Research, Nanjing University, in cooperation with the relevant watershed management authorities, has developed a WebGIS management platform to facilitate this complex process. Improve the management of watersheds over the Huaihe basin through the development, promotion and use of a web-based, user-friendly, geospatial watershed management data and decision support system (WMDDSS) involved many difficulties for the development of this complicated System. In terms of the spatial and temporal characteristics of historic and currently available information on meteorological, hydrological, geographical, environmental and other relevant disciplines, we designed an object-oriented spatiotemporal data model that combines spatial, attribute and temporal information to implement the management

  20. Calculation and interpretation of crustal shortening along the Central Basin Platform, West Texas: A method to calculate basement motion for modeling input

    SciTech Connect

    Hoak, T.E. |; Sundberg, K.R.; Ortoleva, P.

    1998-12-31

    The analysis carried out in the Chemical Interaction of Rocks and Fluids Basin (CIRFB) model describes the chemical and physical evolution of the entire system. One aspect of this is the deformation of the rocks, and its treatment with a rigorous flow and rheological model. This type of analysis depends on knowing the state of the model domain`s boundaries as functions of time. In the Andrews and Ector County areas of the Central Basin Platform of West Texas, the authors calculate this shortening with a simple interpretation of the basic motion and a restoration of the Ellenburger formation. Despite its simplicity, this calculation reveals two distinct periods of shortening/extension, a relatively uniform directionality to all the deformation, and the localization of deformation effects to the immediate vicinities of the major faults in the area. Conclusions are drawn regarding the appropriate expressions of these boundary conditions in the CIRFB model and possible implications for exploration.

  1. Glacioeustatic cyclicity of a Pennsylvanian carbonate platform in a foreland basin setting: An example from the Bachende Formation of the Cantabrian Zone (NW Spain)

    NASA Astrophysics Data System (ADS)

    Corrochano, Diego; Barba, Pedro; Colmenero, Juan R.

    2012-03-01

    By analysis of outcrop data, sequence stratigraphy was used to interpret the stratal architecture and evolution of a Moscovian (Pennsylvanian) carbonate platform (Bachende Formation) located in the Variscan foreland basin of the Cantabrian Zone (NW Spain). The Bachende Formation represents a delta-top carbonate platform developed in highly subsiding (average subsidence rate of 254 m/My) distal shelf areas of the basin. It reached a thickness of 650 m and covered an area of ~ 170 km2 (after conservative palinspastic restorations). The platform interior succession is mostly composed of low-relief mound-shaped micritic boundstones, alternating with bioclastic mudstones/wackestones, peloidal-foraminiferal packstones/grainstones, calcareous algal bafflestones and skeletal and ooidal grainstones. Landwards (to the W), carbonate platform beds alternate and interfinger with deltaic sandstones and shallow marine shales. The platform interior consists of three sequences (S1, S2 and S3), ranging from 180 to 230 m in thickness and from 1.3 to 0.5 My in age. These sequences are in turn subdivided into several meter-scale (10.6 m average thickness), high-frequency (110 to 15 ky), subtidal transgressive-regressive cycles. These cycles are bounded by subaerial exposure or marine flooding surfaces and are inferred to be laterally continuous across the platform-top. They vary from mixed carbonate-siliciclastic to carbonate-dominated cycles. Cyclicity on the Bachende platform was strongly influenced by glacioeustatic sea level variations and changes in subsidence and sedimentation rates. Subaerial exposure surfaces capping high-frequency cycles are better developed in the sequence 1 (late Kashirian/early Podolskian), when subsidence was relatively low and glacioeustatic sea level fluctuations could have exposed subtidal deposits during base-level falls. On the basis of the conservative estimated duration of each cycle and spectral analysis of cycle thickness, the precessional (~ 20

  2. High resolution sequence stratigraphy in the upper Jurassic carbonate platform of the Paris basin: Reservoir geometries in lagoonal, protected marine and ooids shoals environments

    SciTech Connect

    Pascal, H.; Villalobos, L. Guillocheau, F.

    1995-08-01

    Reservoir geometry reconstruction within carbonate platforms has been carried out in the Upper Jurassic of the Paris Basin based on high-resolution sequence stratigraphy correlations (cores and well-logs). 18 cored wells over 25 kM{sup 2} have been correlated (Saint-Clair-sur-Epte field, Gaz de France). During lower and middle Oxfordian the Paris Basin is a carbonate platform prograding southward. This progradational trend can be subdivided into three upper order sequences (parasequences sets, mean duration: one m.y.). The lower parasequence-set is a stacking of shallowing-upward parasequences made up of tidal ooids bars surrounded laterally and backward by more protected environments (large variety of coated grains). The middle parasequence-set is recorded in lagoonal environments with numerous channels and lobes of storm washover-fans. Metric-thick sequences have been correlated over the field. They are ernersive upward (subtidal lagoonal deposits cut by storm-induced channels and lobes, covered by small karsts). The upper parasequence-set is made-up of protected-marine deposits grading into lagoonal sediments. The metric thick shallowing-upward sequences are composed by sheet-shaped, strongly bioturbated, medium to coarse-grained bioclastic limestones. Correlation levels are the deepest facies (strongly monospecifically bioturbated wackstones). Shape and size of reservoirs will be quantified.

  3. Plio-Quaternary Stepwise Aridification of the Asian Inland: Multi-Proxy Records from a 938.5m Drill Core in the Western Qaidam Basin, NE Tibet Plateau

    NASA Astrophysics Data System (ADS)

    Fang, X.; Xi, X.; Li, M.; Appel, E.

    2014-12-01

    The Qaidam Basin is a largest closed basin in the northeastern Tibetan Plateau which is now under hyperarid climate. A 938.5 m-long core was drilled in the Qahansilatu depression in the western Qaidam Basin with an average core recovery rate of 95%. It consists of lacustrine grayish mudstone and siltstones with upperward increasing interbedded salt layers. High resolution paleomagnetic and OSL-U/Th dating of the core determine the core formed between 2.77 Na and 0.1 Ma. Detailed examinations of lithofacies, evaporative minerals, carbon and oxygen isotopes, grain size, bioproductivity and redox conditions collectively reveal that the climate was dry since 2.77Ma and became intensively dried at about 2.5 Ma, 2.2 Ma, 1.6 Ma, 1.2 Ma, 0.9 Ma, 0.6 Ma and 0.1 Ma. Accompanying this stepwise aridifications is the phased shrinkage of the paleo-Qaidam lake from the semi-deep brackish lake in early stage via shallow brackish lake and perennial saline lake to playa saline lake in late stage and completely dried out at the end. Episodic global cooling and tectonic uplift of the NE Tibetan Plateau are possible forcing.

  4. Lateral migration of fault activity in Weihe basin

    NASA Astrophysics Data System (ADS)

    Feng, Xi-Jie; Dai, Wang-Qiang

    2004-03-01

    Lateral migration of fault activity in Weihe basin is a popular phenomenon and its characteristics are also typical. Taking the activity migrations of Wangshun Mountain piedmont fault toward Lishan piedmont fault and Weinan platform front fault, Dabaopi-Niujiaojian fault toward Shenyusi-Xiaojiazhai fault, among a serial of NE-trending faults from Baoji city to Jingyang County as examples, their migration time and process are analyzed and discussed in the present paper. It is useful for further understanding the structure development and physiognomy evolution history of Weihe basin.

  5. Taphonomic and paleoenvironmental considerations for the concentrations of macroinvertibrate fossils in the Romualdo Member, Santana Formation, Late Aptian - Early Albian, Araripe Basin, Araripina, NE, Brazil

    NASA Astrophysics Data System (ADS)

    Prado, Ludmila Alves Cadeira Do; Pereira, Priscilla Albuquerque; Sales, Alexandre Magno Feitosa; Barreto, Alcina Magnólia Franca

    2015-10-01

    Benthic macroinvertebrate fossils can be seen towards to the top of the Romualdo Member of the Santana Formation, in the Araripe Basin, Northeast Brazil, and can provide paleoenvironmental and paleobiogeographical information regarding the Cretaceous marine transgression which reached the interior basins in Northeast Brazil. We analyse taphonomic characteristics of macroinvertebrate concentrations of two outcrops (Torrinha and Torre Grande) within the municipality Araripina, Pernambuco, in order to enhance our understanding of the Cretaceous paleoenvironment in the western portion of the Araripe Basin. At the outcrop Torrinha, proximal tempestitic taphofacies were identified. These predominantly consist of ceritid, cassiopid, and later, naticid gastropods as well as undetermined bivalves. Given this lack of variability it can be deduced that there were no significant paleoenvironmental changes during the successive stages tempestitic sedimentation. In the Torre Grande outcrop distal to proximal tempestitic taphofacies were identified from the base to the top respectively pointing to a decrease in paleodepth. Asides from the macroinvertebrates present in Torrinha, there are also echinoids - unequivocal evidence for marine conditions. These occurrences appear to be restricted to Romualdo Member outcrops in the Araripina municipality (the Southeast portion of the Araripe Basin) confirming a previously published hypothesis suggesting that the Cretaceous marine transgression originated from the neighbouring Parnaíba Basin to the west. This study identified marine molluscs of a similar age to those in the Romualdo Member's equivalent rock units in the Parnaíba and Sergipe-Alagoas (SE-AL) basins suggesting a marine connection between these basins and the Araripe Basin during the Early Cretaceous.

  6. Computer aided graphics simulation modelling using seismogeologic approach in sequence stratigraphy of Early Cretaceous Punjab platform, Central Indus Basin, Pakistan

    SciTech Connect

    Qureshi, T.M.; Khan, K.A.

    1996-08-01

    Modelling stratigraphic sequence by using seismo-geologic approach, integrated with cyclic transgressive-regressive deposits, helps to identify a number of non-structural subtle traps. Most of the hydrocarbons found in Early Cretaceous of Central Indus Basin pertain to structural entrapments of upper transgressive sands. A few wells are producing from middle and basal regressive sands, but the massive regressive sands have not been tested so far. The possibility of stratigraphic traps like wedging or pinch-out, a lateral gradation, an uplift, truncation and overlapping of reservoir rocks is quite promising. The natural basin physiography at times has been modified by extensional episodic events into tectono-morphic terrain. Thus, seismo scanning of tectonically controlled sedimentation might delineate some subtle stratigraphic traps. Amplitude maps representing stratigraphic sequences are generated to identify the traps. Seismic expressions indicate the reservoir quality in terms of amplitude increase or decrease. The data is modelled on computer using graphics simulation techniques.

  7. Tertiary Tectonics of the West Qinling Fault Zone : evidence from deformation, sedimentation, and magneto-stratigraphy in associated basins in the NE Tibetan plateau

    NASA Astrophysics Data System (ADS)

    Wang, Z.; Brian, H.; Lease, R. O.; Garzione, C. N.; Zhang, P.

    2012-12-01

    The West Qinling fault zone (WQFZ) is one of the important NWW-trending faults in the northeastern margin of the Tibetan plateau. Field work in Longxi and Wushan region of the east Gansu province indicates that thrust faulting predominated the history of the fault belt in Cenozoic time, while strike-slip movement probably did not appear until the middle Miocene. We argue here that WQFZ has been so sensitive a structure that its Cenozoic activities may be related to the collision between India and Eurasia and the rising of the Tibetan plateau. Reverse faulting and associated mountain uplift along WQFZ at ˜45-50 Ma has been inferred with thermo-chronological dating in its west segment. According to our research, about 30% shortening occurred during the late Paleogene deformation in the Tange basin south of the WQFZ, while significant shortening for regions north of the WQFZ occurred no earlier than the middle Miocene. This shows that the WQFZ became the early northern boundary of the Tibetan Plateau during the late Paleogene. Basin geometry, magnetostratigraphy, sedimentation characteristics and the early syn-depositional deformation indicates that the Wushan basin with ~1700 m of sedimentary rocks generated in association with transpressional deformation along the WQFZ since ~16 Ma when another pulse of uplift and/or deformation began across the north and east margin of the Tibetan plateau. Furthermore, the WQFZ may have played an important role in the process of basin segmentation initiated since ~22 Ma in the region from the Qinghai lake to the east part of Gansu province. We suggest that the middle Miocene (~16 Ma) may represent a change in kinematics and deformation style in the region along and to the south of the WQFZ. At this time, there was a transition from NNE-SSW compressional deformation that dominated the region since the late Paleogene to the development of WNW-ESE and/or E-W trending strike-slip movement and associated transpressional and

  8. Brasiliano crustal structure and the tectonic setting of the Parnaíba basin of NE Brazil: Results of a deep seismic reflection profile

    NASA Astrophysics Data System (ADS)

    Daly, Michael C.; Andrade, Vander; Barousse, Chuck A.; Costa, Rafaela; McDowell, Kenneth; Piggott, Neil; Poole, Alan J.

    2014-11-01

    A 1430 km, deep crustal, seismic reflection profile of the Parnaíba basin shows an asymmetric, structured western margin and a gently dipping eastern margin. The ~3 km thick, Phanerozoic sedimentary section overlies a pronounced, planar, regional unconformity that crosses three Precambrian blocks with differing seismic facies: the Amazonian/Araguaia block, the Parnaíba block, and the Borborema block. The blocks are separated by steep crustal-scale boundaries across which seismic facies change abruptly. In the west, the ophiolitic metasedimentary rocks of the Araguaia Group overlie the Amazonian craton. Both craton and metasediments terminate eastward against a steep, east dipping fault zone defining the Amazonian/Araguaia block and Parnaíba block boundary. Reactivation of this Neoproterozoic margin in the Late Triassic and Late Jurassic/Early Cretaceous, folded and elevated basement and basin over 2 km. A second crustal boundary defines the eastern margin of the Parnaíba block with the Neoproterozoic Borborema block. This boundary is interpreted as the extension of the Transbrasiliano shear zone. These data demonstrate that the basement of the Parnaíba basin was formed during Brasiliano orogenesis by west directed collision-related thrusting, succeeded by lateral accretion along steep, crustal-scale boundaries. After formation of a post-Brasiliano peneplain, the Parnaíba basin developed seamlessly across three very different crustal blocks and appears to have been significantly larger than its present outline. No extensive underlying rift system is evident suggesting that basement structure had little to do with basin formation, but that episodic reactivation of the boundary zones and basement fabric has controlled the structuring and preservation of the basin.

  9. Furongian Stable Carbon Isotope Excursions (SPICE and HERB) in the Mixed Carbonate-Siliclastics on an Epeiric Platform of the Taebaeksan Basin, Korea

    NASA Astrophysics Data System (ADS)

    Chung, G. S.; Lim, J. N.; Park, T. Y.; Lee, K. S.; Lee, B. S.; Seo, K. S.

    2014-12-01

    Stable carbon isotope stratigraphy of the Late Cambrian mixed carbonate-siliciclastics from an epeiric platform allows a good stratigraphic marker and interpretation of paleoenvironmental conditions. The SPICE (Steptoean positive carbon excursion) and HERB (Hellnmaria-Red Tops Boundary) events are distinctly developed in the Furongian (Late Cambrian) of mixed carbonate-siliciclastics (Sesong and Hwajeol Formations) deposited on an epeiric platform of the Taebaeksan Basin, Korea, part of the North China Platform. The SPICE event occurs in the Prochuangia mansuyi zone and in the lower part of Chuangia zone of trilobite in the Sesong Formation with the δ13C values ranging from 1.1 to 1.8‰; it occurs in the stratigraphic interval mostly composed of nodular shale, massive to laminated fine sandstone with intercalation of limestone conglomerate beds which is interpreted to have been deposited in the inner to middle ramp. The HERB event begins at about the Eoconodontus notchpeakensis FAD of conodont and ends in the lower part of the range of E. notchpeakensis in the Hwajeol Formation. The HERB event shows negative δ13C values up to -5.5‰ forming a conspicuous and distinctive peak. The HERB event occurs in the stratigraphic interval mostly composed of nodular shale, limestone-shale couplet, and limestone conglomerate which is interpreted to have been deposited in the middle ramp. The onset of HERB event at the E. notchpeakensis FAD in the Taebaeksan basin, Korea suggests that the HERB event may be an excellent tool for intercontinental correlation defining the base of the terminal Cambrian (Stage 10). The paleoenvironmental conditions of the SPICE and HERB events seem to be contrary to each other; the SPICE event may be caused by the high rate of primary production and the high rate burial of organic matter with probable association of the high rate of input of terrigenous sediments. In contrast, the HERB event may be caused by the low rate of primary productivity

  10. Lithospheric structure beneath trans-Carpathian transect from Precambrian platform to Pannonian basin: CELEBRATION 2000 seismic profile CEL05

    NASA Astrophysics Data System (ADS)

    Grad, Marek; Guterch, Aleksander; Keller, G. Randy; Janik, Tomasz; Hegedűs, Endre; Vozár, Jozef; Ślączka, Andrzej; Tiira, Timo; Yliniemi, Jukka

    2006-03-01

    In 2000, a consortium of European and North American institutions completed a huge active source seismic experiment focused on central Europe, the Central European Lithospheric Experiment Based on Refraction or CELEBRATION 2000. This experiment primarily consisted of a network of seismic refraction profiles that extended from the East European craton, along and across the Trans-European suture zone region in Poland to the Bohemian massif, and through the Carpathians and eastern Alps to the Pannonian basin. The longest profile CEL05 (1420 km) is the focus of this paper. The resulting two-dimensional tomographic and ray-tracing models show strong variations in crustal and lower lithospheric structure. Clear crustal thickening from the Pannonian basin (24-25 km thick) to the Trans-European suture zone region (˜50 km), together with the configuration of the lower lithospheric reflectors, suggests northward subduction of mantle underlying Carpathian-Pannonian plate under the European plate. This, however, conflicts with strong geological evidence for southward subduction, and we present three tectonic models that are to not totally mutually exclusive, to explain the lithospheric structure of the area: (1) northward "old" subduction of the Pannonian lithosphere under the East European craton in the Jurassic-Lower Cretaceous, (2) a collisional zone containing a "crocodile" structure where Carpatho-Pannonian upper crust is obducting over the crystalline crust of the East European craton and the Carpathian-Pannonian mantle lithosphere is underthrusting cratonic lower crust, and (3) lithosphere thinning due to the effects of Neogene extension and heating with the slab associated with "young" subduction southward in the Miocene having been either detached and/or rolled back to the east. In the last case, the northwestward dipping in the lithosphere can be interpreted as being due to isotherms that could represent the lithosphere/asthenosphere boundary in the Pannonian region.

  11. New paleomagnetic pole from Precambrian magmatic bodies of the Kotuy river basin (northwestern part of the Siberian platform)

    NASA Astrophysics Data System (ADS)

    Veselovskiy, R.; Pavlov, V.

    2009-04-01

    Apparent polar wander paths are powerful means for deciphering of tectonic history of the Earth lithosphere and its structural elements. At the same time APWP's can be used as a tool for dating of different geological events and objects. Importance of APWP's especially increases when dealing with Precambrian where possibilities of many other methods of dating become limited. Whereas Proterozoic APWP's of North American, East European and Australian ancient platforms are more or less developed, Siberian Apparent Polar Wander Path is at the first stage of its elaboration. Proterozoic and, especially, Meso- and Paleoproterozoic paleomagnetic poles are scarce and for long time intervals are practically absent. Thus every new reliable Siberian paleomagnetic pole of Proterozoic age is of paramount importance for elaboration of Proterozoic APWP of the Siberian platform. To obtain such the pole we have carried out paleomagnetic investigation of Late Precambrian magmatic complex of northwestern part of the Anabar Uplift (Siberian platform). In total, six dolerite subvolcanic intrusions (dykes and sills) exposed along the Kotuy, Kotuykan and Djogdjo rivers have been studied. Clear paleomagnetic record was found in 5 intrusions. Thermal demagnetization isolates two magnetic components. The first of them is parallel to the recent geomagnetic field at the site and is removed in the low to middle temperature range. The second one (HTC) is isolated at higher temperatures (up to 600°C) and has dual magnetic polarities. Intrusions means form relatively tight cluster, which average direction corresponds to paleomagnetic poles with coordinates: Plat=-23.4°N, Plong=70.0°E, dp/dm = 3.4°/6.7°. Two polarity distribution of HTC vectors, no resemblance to paleomagnetic poles of younger age, and relative proximity to poles of close age (Ernst et al., 2000; Veselovskiy et al., 2006, 2009) - all these allow us to consider the paleomagnetic pole as reflecting the direction of geomagnetic

  12. Depth distribution of the sedimentary basin and Moho undulation in the Yellow Sea, NE Asia interpreted by using satellite-derived gravity field

    NASA Astrophysics Data System (ADS)

    Choi, Sungchan; Ryu, In-Chang; Götze, H.-J.

    2015-07-01

    We interpreted the TRIDENT satellite derived gravity field to provide detailed insights into the spatial distribution of the crustal density structures in the area of the Yellow Sea. We used 3-D forward density modelling for the interpretation that incorporated constraints from existing geological and geophysical information. A gravity stripping method is used to separate out the gravity effects of different geological crustal structures. From this analysis we see that (1) the Gunsan sedimentary basin is isostatically compensated. (2) The satellite-derived Bouguer anomalies ranging from 15 to -30 × 10-5 m s-2 are linked to basin thicknesses in the Yellow Sea. (3) The calculated Moho depth in the Yellow Sea varies from 27 km beneath the deep sedimentary basin to 34 km in the uplifted zones. (4) Moho depth calculations show two distinct areas, characterized by the deepest Moho depths and the largest crustal thicknesses in the Yellow Sea. The one region extends along the Qianliyan Uplift Zone from Jiaodong to Hongsung while the other area extends from southeastern China to Hongsung in the Korean peninsula. Compared to previous works we suggest that they are the part of the collisions zone between North and South China Blocks extending from China to the Korean peninsula via the Yellow Sea.

  13. Multi-scale factors controlling the pattern of floodplain width at a network scale: The case of the Rhône basin, France

    NASA Astrophysics Data System (ADS)

    Notebaert, Bastiaan; Piégay, Hervé

    2013-10-01

    In this study the floodplain width (FW) was assessed for the entire Rhône catchment river network (32,160 km long) to highlight controlling factors. The FW data, which is measured every kilometre on a digital elevation model (DTM), is aggregated into spatial homogenous segments using a Pettitt break detection test, resulting in aggregated geographical objects (AGO). Based on these AGOs, an analysis of the variability of the floodplain width was performed. The general pattern for the Rhône network shows a downstream increase in FW related to the concept of river continuum. This general pattern explains ca. 30% of the variation in FW. Deviations from this general trend are, however, large. Values for floodplain widths are normalized for catchment scale to study deviations that do not depend on scale effects. Based on a conceptual model, the main environmental parameters influencing FW were identified. These parameters include lithology and different parameters that influence the river profile, such as base level changes and tectonics, sediment load and discharge. An analysis of catchment-wide patterns shows that the main variations on the scaling effect are caused by lithology. Superposed on this general scaling pattern, disturbed by lithological variations, are the variations in floodplain width caused by disturbances in the geomorphic system, which influence floodplain slope, sediment, and water discharge and which include inherited landscapes. Although large data sets become increasingly available and the applied methodology reduces data noise, data availability and quality still hampers studies at a larger scale. Nevertheless, such information sources are becoming crucial because they are more and more accessible and diverse, and the analysis is now easier with the increasing capacities of GIS technologies. As a result, they are becoming very complementary to field studies to understand geomorphic processes at wider spatial and longer temporal scales. In a

  14. Hidden Intra-Basin Extension: Evidence for Dike-Fault Interaction from Magnetic, Gravity, and Seismic Reflection Data in Surprise Valley, NE California

    NASA Astrophysics Data System (ADS)

    Athens, N. D.; Klemperer, S. L.; Glen, J. M. G.; Egger, A. E.

    2015-12-01

    In continental rift zones, the proportion of strain accommodated by tectonic and magmatic processes, as well as their spatial and temporal distribution, is highly variable. Magnetic, gravity, and seismic reflection data in Surprise Valley, CA, in the northwest Basin and Range, reveal an intra-basin, fault-controlled, ~10 m thick dike at a depth of ~150 m, providing a unique example of the interplay between faulting and magmatism in the process of continental rifting. The dike, likely a composite structure representing multiple successive intrusions, is inferred from modeling a positive magnetic anomaly that extends ~35 km and parallels the basin-bounding Surprise Valley normal fault on the west side of the valley. A 2D high-resolution seismic reflection profile acquired across the magnetic high images a normal fault dipping 56°E with ~275 m of throw. Densely spaced gravity measurements reveal a <1 mGal gravity low consistent with the offset along the fault inferred from the seismic data. Co-location of the magnetic high and gravity low for ~6 km implies normal fault control of the dike along that length. The unusually shallow angle of the dike suggests that motion along the fault (perhaps aided by reduced friction along the dike) and associated block rotation resulted in post-intrusion tilting of the dike. The source of the dike is likely related to a shallow brittle-ductile transition zone that was elevated following rapid slip on the Surprise Valley fault post-3 Ma. Prior to this work, the Surprise Valley fault was assumed to accommodate the vast majority of extension across the region. Our results indicate that subsurface features, though no longer active, are significant contributors to the processes, timing, and total amount of extension observed in continental rift environments.

  15. Spatio-temporal variability in Ebro river basin (NE Spain): Global SST as potential source of predictability on decadal time scales

    NASA Astrophysics Data System (ADS)

    Gámiz-Fortis, S. R.; Hidalgo-Muñoz, J. M.; Argüeso, D.; Esteban-Parra, M. J.; Castro-Díez, Y.

    2011-11-01

    SummaryThis paper investigates the spatial and temporal variability of streamflow in the Ebro river basin and its potential predictability. Principal Component Analysis applied to monthly streamflow series from 83 gauging stations distributed through the basin, reveals three homogeneous regions: Basque-Cantabrian, Pyrenees and Southern Mediterranean. Attending to this classification the main characteristic time scales of the maximum monthly streamflows are studied by Singular Spectral Analysis (SSA). Decadal variations in streamflow make particularly large contributions to year-to-year streamflow variance in stations placed in the Basque-Cantabrian and Southern Mediterranean regions, while for the Pyrenees flows the interannual contribution is more important. The predictability of the Ebro flow anomalies has been investigated using a combined methodology: at decadal time scales SST anomalies from several regions provide a significant source of predictability for the Ebro flow, while at interannual time scales autoregressive-moving-average modelling, applied to the time series previously filtered by SSA, is able to provide potential skill in forecasting. For gauging stations associated to the Basque-Cantabrian region significant correlations between the maximum monthly streamflow anomalies and a tripole-like pattern in the North Atlantic SSTs during the previous spring are found. This association is found maximum and stable for the tropical part of the pattern (approximately 0-20°N). For the gauging stations placed to the southeast of basin some influence from the Pacific Decadal Oscillation (PDO) is found. This method allows evaluating, independently, the decadal and interannual predictability of the streamflow series. In addition, the combination of both modelling techniques gives as result a methodology that has the capacity to provide basin-specific hydroclimatic predictions which vary (for the 1990-2003 validation period) between 62% for the Basque

  16. Magnetostratigraphy and Susceptibility of Deep Drilling Core SG-1 in the Western Qaidam Basin (ne Tibetan Plateau) and Their Tectonic and Climatic Implications

    NASA Astrophysics Data System (ADS)

    Fang, X.; Zhang, W.; Appel, E.; Song, C.

    2013-05-01

    The Qaidam Basin is the largest intermontane basin of the northeastern Tibetan Plateau and contains a continuous Cenozoic sequence of lacustrine sediments. A nearly 1000 m deep drilling (SG-1) with an average core recovery of ~95% was carried out in the depocenter of the western Qaidam Basin, aimed to obtain a high-resolution record of the paleoenvironmental evolution and the erosion history. The core consists of dark grayish mudstone and grayish siltstone, intercalated with salts and fine sandstones in the upper part. Stepwise alternating field and thermal demagnetization, together with rock magnetic results, revealed a stable remanent magnetization for most samples, carried by magnetite. The polarity sequence consists of sixteen normal and fifteen reverse zones which can be correlated with chrons 1n to 2An of the global geomagnetic polarity time scale. Magnetostratigraphic results date the entire core SG-1 at ~2.77 Ma to ~0.1 Ma and yield sediment accumulation rate (SAR) ranging from 26.1 cm/ka to 51.5 cm/ka. Maximum SARs occur within the intervals of ~2.6-2.2 Ma and after ~0.8 Ma indicating two episodic erosional periods. Detailed magnetic susceptibility and rock magnetic properties were analyzed for revealing the significance of ferro(i)magnetic concentration for past changes of climate and erosion. Mass-specific susceptibility (χ) shows a striking cyclic and long-term variation. Samples with high χ values are dominated by magnetite and maghemite with pseudo-single-domain properties. In contrast, samples with low χ values contain maghemite from single-domain to multi-domain, and additionally a significant fraction of hematite. Combining with high resolution pollen-spore and geochemical records for representative time intervals, the driving mechanism of χ variation can be explained by low-temperature oxidation in the lake sediments (dry climate). Trends of match with sedimentation rates and are roughly synchronous with the deep-sea δ18O record on a glacial

  17. Dynamic response signatures of a scaled model platform for floating wind turbines in an ocean wave basin.

    PubMed

    Jaksic, V; O'Shea, R; Cahill, P; Murphy, J; Mandic, D P; Pakrashi, V

    2015-02-28

    Understanding of dynamic behaviour of offshore wind floating substructures is extremely important in relation to design, operation, maintenance and management of floating wind farms. This paper presents assessment of nonlinear signatures of dynamic responses of a scaled tension-leg platform (TLP) in a wave tank exposed to different regular wave conditions and sea states characterized by the Bretschneider, the Pierson-Moskowitz and the JONSWAP spectra. Dynamic responses of the TLP were monitored at different locations using load cells, a camera-based motion recognition system and a laser Doppler vibrometer. The analysis of variability of the TLP responses and statistical quantification of their linearity or nonlinearity, as non-destructive means of structural monitoring from the output-only condition, remains a challenging problem. In this study, the delay vector variance (DVV) method is used to statistically study the degree of nonlinearity of measured response signals from a TLP. DVV is observed to create a marker estimating the degree to which a change in signal nonlinearity reflects real-time behaviour of the structure and also to establish the sensitivity of the instruments employed to these changes. The findings can be helpful in establishing monitoring strategies and control strategies for undesirable levels or types of dynamic response and can help to better estimate changes in system characteristics over the life cycle of the structure. PMID:25583866

  18. Dynamic response signatures of a scaled model platform for floating wind turbines in an ocean wave basin

    PubMed Central

    Jaksic, V.; O'Shea, R.; Cahill, P.; Murphy, J.; Mandic, D. P.; Pakrashi, V.

    2015-01-01

    Understanding of dynamic behaviour of offshore wind floating substructures is extremely important in relation to design, operation, maintenance and management of floating wind farms. This paper presents assessment of nonlinear signatures of dynamic responses of a scaled tension-leg platform (TLP) in a wave tank exposed to different regular wave conditions and sea states characterized by the Bretschneider, the Pierson–Moskowitz and the JONSWAP spectra. Dynamic responses of the TLP were monitored at different locations using load cells, a camera-based motion recognition system and a laser Doppler vibrometer. The analysis of variability of the TLP responses and statistical quantification of their linearity or nonlinearity, as non-destructive means of structural monitoring from the output-only condition, remains a challenging problem. In this study, the delay vector variance (DVV) method is used to statistically study the degree of nonlinearity of measured response signals from a TLP. DVV is observed to create a marker estimating the degree to which a change in signal nonlinearity reflects real-time behaviour of the structure and also to establish the sensitivity of the instruments employed to these changes. The findings can be helpful in establishing monitoring strategies and control strategies for undesirable levels or types of dynamic response and can help to better estimate changes in system characteristics over the life cycle of the structure. PMID:25583866

  19. Devonian/Carboniferous boundary glacioeustatic fluctuations in a platform-to-basin direction: A geochemical approach of sequence stratigraphy in pelagic settings

    NASA Astrophysics Data System (ADS)

    Bábek, Ondrej; Kumpan, Tomáš; Kalvoda, Jiří; Matys Grygar, Tomáš

    2016-05-01

    in the most distal pelagic sections. Consequently, the previous interpretation of the HBE black shale as a condensed succession deposited during rapid sea-level rise seems unlikely. We interpret the HBE s.l. (i.e., including the HBE black shale) as a marine record of glacioeustatic sea-level drop and increased aeolian transport in connection with late Devonian climatic cooling and glaciation. The set of geochemical markers related to the late Devonian sea-level fluctuation can be used for super-regional to global correlations from platform to basin settings. Moreover, they can facilitate current efforts to determine a new D/C boundary definition.

  20. Modelling the coupled fluid and heat transport in a geothermal site: First results from Groß Schönebeck, NE-German Basin

    NASA Astrophysics Data System (ADS)

    Cherubini, Y.; Cacace, M.; Scheck-Wenderoth, M.; Lewerenz, B.

    2010-05-01

    Predicting the temperature distribution in the subsurface becomes increasingly important in the course of recently intensified exploration for geothermal energy. Numerical models considering both the physical processes controlling heat transfer as well as the structural setting of the subsurface are an important option to assess variations in the temperature distribution. The geothermal in-situ laboratory "Groß Schönebeck" located 40 km north of Berlin is one of the key sites of geothermal exploration studies in the North German Basin. 3D numerical simulations of coupled fluid flow and heat transfer processes are carried out to investigate the geothermal field. The Goal of the study is to quantify the impact of variable rock parameters and geological structures on the resulting thermal distribution. The Zechstein salt as a prominent feature in the North German Basin is of particular interest in this context because it locally modifies the geothermal field. Our first attempts to model coupled fluid flow and heat transfer processes confirm the strong impact of the Upper Permian Zechstein salt. Furthermore, our results indicate that conduction is an important heat transfer mechanism below the Middle Triassic layers. Conversely, the more than 3000 m thick and permeable sediments above the Middle Triassic Muschelkalk unit favour the formation of convection cells. Here, especially high degrees of coupling result in remarkable convective heat transport. We assess the sensitivity of these results, and discuss implications for temperature predictions.

  1. Primary uranium sources for sedimentary-hosted uranium deposits in NE China: insight from basement igneous rocks of the Erlian Basin

    NASA Astrophysics Data System (ADS)

    Bonnetti, Christophe; Cuney, Michel; Bourlange, Sylvain; Deloule, Etienne; Poujol, Marc; Liu, Xiaodong; Peng, Yunbiao; Yang, Jianxing

    2016-05-01

    Carboniferous-Permian, Triassic and Jurassic igneous basement rocks around the Erlian Basin in northeast China have been investigated through detailed mineralogical, whole-rock geochemistry, geochronological data and Sm-Nd isotope studies. Carboniferous-Permian biotite granites and volcanic rocks belong to a calc-alkaline association and were emplaced during the Late Carboniferous-Early Permian (313 ± 1-286 ± 2 Ma). These rocks are characterised by positive ɛNd(t) (3.3-5.3) and fairly young T DM model ages (485-726 Ma), suggesting a dominant derivation from partial melting of earlier emplaced juvenile source rocks. Triassic biotite granites belong to a high-K calc-alkaline association and were emplaced during the Middle Triassic (243 ± 3-233 ± 2 Ma). Their negative ɛNd(t) (-2 to -0.1) and higher T DM model ages (703-893 Ma) suggest a contribution from Precambrian crust during the magma generation processes, leading to a strong enrichment in K and incompatible elements such as Th and U. Highly fractionated magmas crystallised in U-rich biotite (up to 21 ppm U) and two-mica granites. In biotite granite, the major U-bearing minerals are uranothorite and allanite. They are strongly metamict and the major part of their uranium (90 %) has been released from the mineral structure and was available for leaching. Mass balance calculations show that the Triassic biotite granites may have, at least, liberated ˜14,000 t U/km3 and thus correspond to a major primary uranium source for the U deposits hosted in the Erlian Basin.

  2. Intensified tectonic deformation and uplift of the Altyn Tagh range recorded by rock magnetism and growth strata studies of the western Qaidam Basin, NE Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Han, Wenxia; Fang, Xiaomin; Zhang, Weilin; Song, Chunhui; Yan, Maodu

    2016-02-01

    As the tectonical and geographical northern edge of the Tibetan Plateau, the evolution of the Altyn Tagh range has attracted wide attention. Precise dating of its activities is believed essential for understanding the possible mechanisms of the Tibetan Plateau uplift and its effects on climate changes. Under the framework of basin-mountain coupling, both magnetic susceptibility and rock magnetic researches were carried out in this study on the Late Cenozoic sediments of the Honggouzi (HGZ) section (ca. 17-5 Ma) in the western Qaidam Basin to explore the tectonic and climatic evolution as well as their interactions of the Altyn Tagh range. The obtained magnetic susceptibility record in the HGZ section displayed a two-step variation, which kept relatively low and stable values for sediments from the stratigraphic levels of 120-596 m (ca. 17-10 Ma) (stage I), but increased rapidly from 596 to 1014 m (ca. 10-5 Ma) (stage II). The rock magnetic results revealed that paramagnetic minerals or clay minerals, maghemite and hematite are dominant in stage I, which were replaced by magnetite and maghemite in stage II. A detailed comparison of magnetic susceptibility record in the HGZ section with regional tectonic and climate records was carried out. Combined with sedimentary facies, lithology and angular unconformity in the sequence, as well as seismostratigraphy data, paleocurrent and provenance analyses, the possible mechanisms for the magnetic susceptibility variation were explored. The results indicated a direct link between magnetic susceptibility change and the uplift of the Altyn Tagh range at ca. 10 Ma.

  3. Late Miocene to Pleistocene Environmental Changes in the Western Qaidam Basin (NE Tibetan Plateau) Revealed By Magnetic Properties in Lacustrine Sediments

    NASA Astrophysics Data System (ADS)

    Herb, C.; Appel, E.; Zhang, W.; Koutsodendris, A.; Fang, X.; Pross, J.

    2014-12-01

    The advantage of studying magnetic properties of the lacustrine sediments deposited in the Qaidam paleolake to reconstruct past environmental changes was shown in detail for the 940-m-long drill core SG-1 (2.69-0.08 Ma) recovered from the western Qaidam Basin. Especially magnetic susceptibility (χ) turned out to be a useful proxy indicating past humidity changes in the study region. The causes of χ variation could be related to weathering (low-temperature oxidation) in the catchment area and a changing catchment area, respectively. To benefit further from magnetic properties as high-resolution paleoclimate proxies in the Qaidam paleolake, we expand our magnetic record to the late Miocene by investigating magnetic properties of the 723-m deep drilling SG-1b. While SG-1 was drilled in the flat lying strata of the Chahansilatu sub-basin, SG-1b was recovered from the adjacent Jianshan anticline (in ~20 km distance from SG-1). Magnetostratigraphy of core SG-1b detects a time span ranging from 7.3 to 1.6 Ma, missing the younger sequence as a consequence of the anticline structure. We analyze climatic implications of the magnetic record of SG-1b, especially by observing 750 hysteresis loops and 20 FORC diagrams, and check for small-scale variations of the studied sediments by comparing χ of bulk samples (in the order of 10 g) and samples used for hysteresis measurements (in the order of 0.01 g). Spectral analysis based on the time scale provided by magnetostratigraphy reveals variations of χ in the order of Milankovitch cycles (precession, obliquity, and eccentricity) indicating insolation changes as one important driving factor of the magnetic concentration signal. The magnetic records of SG-1 and SG-1b are also used to check implications of the anticline structure on magnetic signatures by comparing the overlapping interval of both cores (2.69-1.6 Ma).

  4. Geomorphic and stratigraphic evidence of incision-induced halokinetic uplift and dissolution subsidence in transverse drainages crossing the evaporite-cored Barbastro-Balaguer Anticline (Ebro Basin, NE Spain)

    NASA Astrophysics Data System (ADS)

    Lucha, Pedro; Gutiérrez, Francisco; Galve, Jorge Pedro; Guerrero, Jesús

    2012-10-01

    The evaporite-cored Barbastro-Balaguer Anticline, located in the northeastern sector of the Ebro Tertiary Basin, NE Spain, is traversed perpendicularly by several drainages coming from the Pyrenees, including the Cinca, Noguera-Ribagorzana and Segre rivers. The terraces associated with these discordant fluvial systems, deposited upon evaporitic and detrital formations across the anticline, allow the analysis of geomorphic and stratigraphic anomalies related to the soluble and ductile nature of the halite-bearing rocks in the core of the anticline. Geomorphological mapping reveals that the gravels discontinuously capping the evaporitic core of the anticline, together with some alluvial mantles disconnected from the present-day river valleys, constitute the oldest sediments deposited under exorheic conditions in this sector of the Ebro Tertiary Basin. These alluvial deposits inset into the basin fill record an early post-capture palaeogeographic stage during which the drainage was dominated by unconfined distributary channels developed on extensive alluvial fans fed by perennial rivers coming from the Pyrenees. The terraces associated with the present-day fluvial valleys correspond to a later palaeogeographic stage characterized by a well-integrated drainage confined to fluvial valleys entrenched in the basin fill. These terraces show evidence of both dissolution-induced subsidence and halokinesis restricted to areas underlain by the evaporites of the anticline core. The deposits of the highest terrace levels of the Noguera-Ribagorzana and Segre rivers and its tributaries, Lo Reguer Creek and Farfanya River, are locally thickened filling basins generated by dissolution-induced synsedimentary subsidence up to several kilometers long and more than 100 m deep. Subsidence caused by the karstification of the evaporites reached higher magnitude and extent during the early stages of development of the new external drainage network, when the more soluble halite-bearing units

  5. Identification of different groundwater flowpaths within volcanic aquifers using natural tracers for the evaluation of the influence of lava flows morphology (Argnat basin, Chaîne des Puys, France)

    NASA Astrophysics Data System (ADS)

    Bertrand, Guillaume; Celle-Jeanton, Hélène; Huneau, Frédéric; Loock, Sébastien; Renac, Christophe

    2010-09-01

    SummaryHydrochemical and stable isotopic ( 2H, 18O) data were used to characterize the groundwater flow and major chemical features within a complex fractured volcanic aquifer system, the Argnat basin, which is located in the Chaîne des Puys (French Massif Central). From 10 sampling points, the study of the transfer into the saturated zone from upstream to downstream, given the geological context and topography, allows to estimate the role of supply from high and low altitudes to the recharge processes. This work shows the existence of different types of supply between pahoehoe and a'a flows. Therefore, the morphology of volcanic flows impacts the chemical and isotopic signatures of groundwater, enhancing or reducing the influence of the unsaturated zone on the pathways of infiltrated water. Pahoehoe flows imply horizontal water flows of low discharge at the top of the lava whereas a'a flows seems to be much more heterogeneous and locally able to promote the existence of perched water bodies and further vertical circulations. Taking into account these two types of behaviour, a conceptual scheme of the functioning of this heterogeneous environment is proposed, which will help towards a sustainable management of volcanic aquifers in relation with the European Union Groundwater Directive (2006/118/CE) (2006).

  6. Tectonics and sedimentation in the Curitiba Basin, south of Brazil

    NASA Astrophysics Data System (ADS)

    Salamuni, Eduardo; Ebert, Hans Dirk; da Silva Borges, Mauricio; Hasui, Yociteru; Costa, João Batista Sena; Salamuni, Riad

    2003-03-01

    The Curitiba Basin, Paraná, lies parallel to the west side of the Serra do Mar range and is part of a continental rift near the Atlantic coast of southeastern Brazil. It bears unconsolidated and poorly consolidated sediments divided in two formations: the lower Guabirotuba Formation and the overlying Tinguis Formation, both developed over Precambrian basement. Field observations, water well drill cores, and interpretations of satellite images lead to the inference that regional tectonic processes were responsible for the origin of the Basin in the continental rift context and for morphotecatonic evolution through block tilting, dissection, and erosion. The structural framework of the sediments and the basement is characterized by NE-SW-trending normal faults (extensional tectonic D 1 event) reactivated by NE-SW-trending strike-slip and reverse oblique faults (younger transtensional tectonic D 2' to transpressional tectonic D 2″ event). This tectonic event, which started in the Paleogene and controlled the basin geometry, began as a halfgraben and was later reactivated as a pull-apart basin. D 2 is a neotectonic event that controls the current morphostructures. The Basin is connected to the structural rearrangement of the South American platform, which underwent a generalized extensional or trantensional process and, in late Oligocene, changed to a compressional to transpressional regime.

  7. Decadal to Multi-centennial SST Reconstructions From the Anthropocene Into the Last 2 Millennia: Planktonic Foraminiferal Mg/Ca Evidence From San Lazaro Basin (NE Pacific)

    NASA Astrophysics Data System (ADS)

    Mortyn, P. G.; Martínez-Botí, M. À.; Herguera, J. C.

    2009-04-01

    On inter-annual time scales, the El Niño / Southern Oscillation (ENSO) climatic phenomenon is the largest driver of change in the ocean-atmosphere system. Significant impacts also arise from longer-term phenomena at decadal to centennial timescales, such as the Pacific Decadal Oscillation (PDO). It is a primary interest to understand how modern global warming has impacted such drivers of significant climatic impacts, and how the marine sedimentary archive records this linkage in the southern California Current (CC). This would allow detailed comparison against other high-resolution archives, such as corals, and an improved ability to interpret past events as potential analogs for the future of ENSO and PDO. Furthermore, such reconstructions in recent millennia are crucial, since they record pre-anthropogenic climates under interglacial (warm) boundary conditions that allow us to characterize the nature of modern influence on this system. Here we present sub-decadal reconstructions of sea surface temperature (SST), derived from the Mg/Ca ratio of the shallow-dwelling planktonic foraminifera Globigerinoides ruber. The samples come from San Lázaro Basin in the southern Baja California continental margin (25°N; 112°W), situated beneath the dynamic boundary of the cool eastern Pacific boundary CC of northern origin, and the warm subtropical water masses of southern origin. The bottom of this coastal basin (maximum depth of 540m) is bathed by oxygen-depleted waters that flow over a shallow sill at 370m. High levels of primary production and export of biogenic particles to depth ensue from strong seasonal upwelling processes during spring to early summer. This combination of high sediment production and preservation in an area very sensitive to ENSO and PDO impacts allows for a high-resolution reconstruction of inter-annual climatic phenomena in this unique eastern boundary current setting. For our highest temporal detail, we examine 2 cores at interannual resolution

  8. Assessing the sources of uncertainty associated with the calculation of rainfall kinetic energy and erosivity - application to the Upper Llobregat Basin, NE Spain

    NASA Astrophysics Data System (ADS)

    Catari, G.; Latron, J.; Gallart, F.

    2011-03-01

    The diverse sources of uncertainty associated with the calculation of rainfall kinetic energy and rainfall erosivity, calculated from precipitation data, were investigated at a range of temporal and spatial scales in a mountainous river basin (504 km2) in the south-eastern Pyrenees. The sources of uncertainty analysed included both methodological and local sources of uncertainty and were (i) tipping-bucket rainfall gauge instrumental errors, (ii) the efficiency of the customary equation used to derive rainfall kinetic energy from intensity, (iii) the efficiency of the regressions obtained between daily precipitation and rainfall erosivity, (iv) the temporal variability of annual rainfall erosivity values, and the spatial variability of (v) annual rainfall erosivity values and (vi) long-term erosivity values. The differentiation between systematic (accuracy) and random (precision) errors was taken into account in diverse steps of the analysis. The results showed that the uncertainty associated with the calculation of rainfall kinetic energy from rainfall intensity at the event and station scales was as high as 30%, because of insufficient information on rainfall drop size distribution. This methodological limitation must be taken into account for experimental or modelling purposes when rainfall kinetic energy is derived solely from rainfall intensity data. For longer temporal scales, the relevance of this source of uncertainty remained high if low variability in the types of rain was supposed. Temporal variability of precipitation at wider spatial scales was the main source of uncertainty when rainfall erosivity was calculated on an annual basis, whereas the uncertainty associated with long-term erosivity was rather low and less important than the uncertainty associated with other model factors such as those in the RUSLE, when operationally used for long-term soil erosion modelling.

  9. Recent climate trends and multisecular climate variability: temperature and precipitation during the cold season (October-March) in the Ebro Basin (NE of Spain) betrween 1500 and 2008

    NASA Astrophysics Data System (ADS)

    Saz-Sanchez, M.-A.; Cuadrat-Prats, J.-M.

    2009-09-01

    One of the goals of Paleoclimatology is to assess the importance and the exceptional nature of recent climate trends related to the anthropogenic climate change. Instrumental data enable the analysis of last century's climate, but do not give any information on previous periods' precipitation and temperature, during which there was no anthropic intervention on the climate system. Dendroclimatology is one of the paleoclimatic reconstruction sources giving best results when it comes to reconstructing the climate of the time before instruments could be used. This work presents the reconstructed series of precipitation and temperature of the cold season (October-March) In the central sector of the Ebro Valley (NE of Spain). The chronologies used for the reconstruction come on the one hand from the International Tree-Ring Data Bank (ITRDB) and on the other hand from the dendrochronological information bank created in the northern half of the Iberian Peninsula within the framework of the Spanish Interministerial Commission for Science and Technology (CICYT) CLI96-1862 project. The climate data used for chronology calibration and the reconstruction of the temperature and precipitation values are those of the instrumental observatory number 9910 (Pallaruelo) belonging to the Spanish State Meteorological Agency (Agencia Estatal de Meteorología or AEMET), located in the central sector of the Ebro Valley. The reconstruction obtained covers the 1500-1990 period. In order to extend the series up to 2008, instrumental information has been used. Thanks to data from a set of AEMET instrumental observatories close to the one used for chronology calibration, a regional series of temperatures as well as a precipitation one were generated. The series reconstructed through dendroclimatic methods and the regional series do not show statistically significant differences in their mean and variance values. R values between both series exceed 0.85. Taking these statistical characteristics

  10. Geochemistry of the Cretaceous coals from Lamja Formation, Yola Sub-basin, Northern Benue Trough, NE Nigeria: Implications for paleoenvironment, paleoclimate and tectonic setting

    NASA Astrophysics Data System (ADS)

    Sarki Yandoka, Babangida M.; Abdullah, Wan Hasiah; Abubakar, M. B.; Hakimi, Mohammed Hail; Adegoke, Adebanji Kayode

    2015-04-01

    The Cretaceous coals of Lamja Formation located in Yola Sub-basin of the Northern Benue Trough, northeastern Nigeria, were analyzed based on a combined investigation of organic and inorganic geochemistry to define the paleodepositional environment condition, organic matter source inputs and their relation to paleoclimate and tectonic setting. The total organic carbon and sulfur contents of Lamja Formation coals ranges from 48.2%-67.8% wt.% and 0.42%-0.76% wt.%, respectively, pointing their deposition in freshwater environment with inferred marine influence during burial. Biomarkers and chemical compositions provide evidence for a major contribution of land-derived organic matter, with minor aquatic organic matter input. Minerals such as quartz, pyrite, kaolinite, illite, montmorillonite and calcite were present in the coals, suggesting that these minerals were sourced from terrigenous origin with slightly marine influence, considered as post-depositional. This is consistent with a significant amount of the oxides of major elements such as SiO2, Fe2O3, Al2O3, TiO2, CaO, and MgO. The investigated biomarkers are characterized by dominant odd carbon numbered n-alkanes (n-C23 to n-C33), moderately high Pr/Ph ratios (1.72-3.75), very high Tm/Ts ratios (18-29), and high concentrations of regular sterane C29, indicating oxic to relatively suboxic conditions, delta plain marine environment of deposition with prevalent contribution of land plants and minor aquatic organic matter input. Concentrations of trace elements such as Ba, Sr, Cr, Ni, V, Co and their standard ratios also suggested that the organic matter was deposited under oxic to relatively suboxic conditions, which is in parts deposited under marine influenced. Some standard binary plots of SiO2 versus (Al2O3 + K2O + Na2O) indicate a semi-arid paleoclimatic condition whereas log SiO2 versus (K2O/Na2O) also revealed passive continental margin setting. The inferred tectonic setting is in agreement with the tectonic

  11. 4. View of the NE side primary scrubbers with the ...

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

    4. View of the NE side primary scrubbers with the collector main alongside the mezzanine platform; looking NW. (Ryan) - Holston Army Ammunition Plant, Producer Gas Plant, Kingsport, Sullivan County, TN

  12. Response of magnetic susceptibility in Quaternary lacustrine sediments of the Qaidam Basin (NE Tibetan Plateau) to orbital forcing: applying time series analyses to improve magnetostratigraphic dating of drill core SG-1

    NASA Astrophysics Data System (ADS)

    Herb, C.; Appel, E.; Voigt, S.; Zhang, W.; Fang, X.; Koutsodendris, A.; Pross, J.

    2013-12-01

    The Cenozoic lacustrine sediments around the drilling site of the ~940-m-long core SG-1 from the western Qaidam Basin (NE Tibetan Plateau) in the Chahansilatu sub-depression, having a thickness of up to 6,000 m, offer a great archive for studying past climate change. Magnetostratigraphic dating of SG-1 reveals an average sediment accumulation rate of 35 cm/kyr and a time span ranging from ~2.8 to ~0.1 Ma. Beside several non-magnetic proxies, mass-specific magnetic susceptibility (χ) shows a response to past environmental change. The χ time series displays high-amplitude cyclicities (beside long-term trends), which can be attributed to orbital forcing. Major Milankovitch cycles can be detected as well as the occurrence of spectral power near periods corresponding to nonlinear responses to orbital forcing (near the typical periods of ~30, ~54, and ~70 ka). The Middle Pleistocene Transition (MPT; ~1.2-0.7 Ma) can also be observed in the χ record of SG-1, represented by a typical shift of main spectral power in the 41-kyr obliquity to an additional appearance of the 100-kyr eccentricity band. We attempt to use this climate forced signals of the χ record to establish a more detailed depth-to-time transformation for drill core SG-1 based on cyclostratigraphy and spectral analysis of χ in windows, with the magnetic polarity boundaries as tie points. Due to the changing spectral power of the Milankovitch cycles along the core, SG-1 has to be divided into different parts with different prominences of the 41- and 100-ka cycle, as well as cycles originating from nonlinear climate responses.

  13. Séquences de dépôt à l'articulation plate-forme urgonienne bassin (intervalle Barrémien Albien) dans le Prébalkan occidental (Bulgarie du Nord-Ouest)Depositional sequences at the Urgonian platform/basin transition (Barremian Albian interval) in the western Fore-Balkan (northwest Bulgaria).

    NASA Astrophysics Data System (ADS)

    Peybernès, Bernard; Ivanov, Marin; Nikolov, Todor; Ciszak, Richard; Stoykova, Kristalina

    2000-04-01

    In the western Fore-Balkan (northwest Bulgaria), the characterization of numerous depositional sequences within the Barremian-Albian interval allows us to reconstruct from southeast to northwest the successive palaeogeographies of this part of the north Tethyan margin: two carbonate (Urgonian) platforms flanking a central terrigenous basin during the Barremian; a single centrifugal terrigenous basin (Aptian) marked, along its axis, by an olistostrome and siliciclastic turbidites; a single Albian basin characterized by the stacking of glauconite-rich condensation sections and anoxic black marls.

  14. (U Th) / Ne chronometry

    NASA Astrophysics Data System (ADS)

    Gautheron, C. E.; Tassan-Got, L.; Farley, K. A.

    2006-03-01

    Production of 21Ne from the reaction 18O( α, n) 21Ne in U and Th rich minerals such as apatite, zircon, monazite and titanite can potentially be used for chronometry. Based on a review of the available cross section data we reevaluated the production of 21Ne from this reaction using a thin target approach and compared the results against thick target situations. The ( 21Ne / 4He) production ratio in these minerals is about 4 × 10 - 8 , but varies with oxygen content and Th / U ratio. 21Ne has a stopping range of about 1 μm compared to about 20 μm for α particles; thus the ( 21Ne / 4He) production ratio also depends on crystal size when the crystals are small enough that α ejection is important. Using a Monte Carlo model we computed the effects of ejection on the ( 21Ne / 4He) ratio for various geometries and grain sizes. We also present measurements of the ( 21Ne / 4He) ratio on few mg aliquots of well-dated volcanic apatites and zircons for which the duration of retention of 21Ne and 4He is the same. Values of (4.4 ± 1.1) × 10 - 8 and (3.5 ± 1.2) × 10 - 8 for apatite and zircon, respectively, are in agreement with the theoretical values of (4.16 ± 0.14) × 10 - 8 ; (3.54 ± 0.13) × 10 - 8 . Based on our production rate estimates the Durango apatite and Fish Canyon Tuff zircon give Ne ages of 34.2 ± 8.6 and 28 ± 12 Ma, respectively, which are in agreement with independently known ages. Our results demonstrate that the 21Ne production is well understood and can be used to measure the neon retention time for slowly cooled minerals. The 4He and 21Ne content of zircons from the deeply exhumed crustal section in Gold Butte, Nevada (crystallization age of 1.4 Ga) imply (U-Th) / Ne ages of 963 ± 164 and 777 ± 122 Ma, far older than their He ages of 16.7 ± 1.3 and 19.1 ± 1.5 Ma, respectively. To explain the age difference, a neon closure temperature for zircon between the values given by the thermochronometers U-Pb on apatite and Ar-Ar on muscovite is

  15. NARSTO NE MODEL

    Atmospheric Science Data Center

    2014-04-25

    ... Station Instrument:  Chemiluminescence UV Ozone Detector Location:  Northeastern United States ... Files:  NE Model Readme Hourly Surface Air Quality Ozone & Nitrogen Measurement Sites Related Data:  ...

  16. MiniBooNE

    SciTech Connect

    Stefanski, Ray; /Fermilab

    2009-10-01

    To begin, we examine the relationship between MiniBooNE and the neutrino beam geometry at Fermilab. In Figure 1, a schematic representation is shown of the plan view of the location of MiniBooNE relative to SciBooNE and the NuMI target, where it can be seen that SciBooNE and MiniBooNE share the same beamline and neutrino flux, and therefore share some of the same systematic effects -- A combined analysis between the two experimental groups could yield a superior result compared to segregated individual analysis. MiniBooNE makes an angle of 6.3 degrees with the NuMI beamline, an off-axis measurement if you will, that provides a relatively high yield of electron neutrinos from kaon decay. Furthermore, the proton beam incident on the MiniBooNE target possesses a 53 MHz structure that will be important in timing studies related to the low energy excess. Let's review of the results of the MiniBooNE: As is well known, MiniBooNE, a test of the LSND effect [1], adds experimental inspiration to the possible existence of new phenomena; although two neutrino-family oscillations were shown to be an unlikely candidate to explain the LSND effect, a low energy excess of 3.0 sigma in the neutrino sector at energies between 200 to 475 MeV [2] - an effect that appears to have no counterpart in the antineutrino sector [3], combined with the 3.8 sigma LSND result - at roughly 50 MeV - strains phenomenology for insight. Miniboones continues to run and collect antineutrino data; will combine disappearance analysis with SciBooNE; take data from the NuMI target, an unusual source with a potentially new look at the low energy anomaly; and use beam timing techniques to further constrain phenomenological models. In this paper we will review current topics related to MiniBooNE and other associated experiments and phenomenology.

  17. MiniBooNE

    SciTech Connect

    Mahn, Kendall Brianna Mcconnel; /Columbia U.

    2007-03-01

    MiniBooNE is a short baseline neutrino experiment designed to confirm or refute the LSND observed excess of electron anti neutrinos in a muon anti neutrino beam. The experimental setup, data samples, and oscillation fit method are discussed. Although the result was not public at the time of the talk, MiniBooNE has since published results, which are discussed briefly as well.

  18. Tectonic framework of Turkish sedimentary basins

    SciTech Connect

    Yilmaz, P.O. )

    1988-08-01

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

  19. Styles of deposition and diagenesis in the Monahans Clear Fork reservoir: Implications for improved characterization of Leonard reservoirs on the Central basin platform

    SciTech Connect

    Ruppel, S.C. )

    1992-04-01

    The Leonard Series (Lower Permian) of west Texas contains a substantial hydrocarbon resource; the original oil in place in these predominantly carbonate rocks totaled about 14.5 billion bbl. Recovery of this resource has proven difficult, however. Current recovery efficiencies average about 20%, far below the 35% average for other Permian basin carbonate reservoirs. Detailed characterization of the Leonard in the Monahans field (Ward and Winkler counties, Texas) illustrates that poor reservoir performance in these reservoirs is the result of extreme lithologic heterogeniety resulting from cyclic rise and fall of relative sea level. Patterns of both depositional and diagenetic facies are a function of this cyclicity. Three orders of cyclicity are apparent in the Leonard: high-frequency, fifth-order cycles averaging 1-2 m in thickness, fourth-order cycles averaging 15-20 m in thickness, and third-order cycles averaging 200 m in thickness. Diagenetic patterns reflect control by fourth-order and third-order cyclicity. Both depositional and diagenetic trends are modified by local topography. Porosity and permeability also manifest cycle-related trends. Porosity and permeability exhibit opposite relationships to paleotopography. Porosity, which is encountered in tidal-flat and subtidal facies, is greatest on paleotopographic highs, whereas permeability, which is most commonly developed in subtidal facies, is most common on paleotopographic lows. Preliminary investigation of Leonard carbonate sequences elsewhere in the Permian basin reveals analogous styles and patterns of facies development. The concepts and models developed in the Monahans field should help improve characterization of these sequences as well.

  20. Tectonic evolution and paleogeography of the Mesozoic Pucará Basin, central Peru

    NASA Astrophysics Data System (ADS)

    Rosas, Silvia; Fontboté, Lluís; Tankard, Anthony

    2007-06-01

    The Pucará Basin of Peru is an elongate trough that subsided landward of a NNW-trending structural high during the Late Triassic-Early Jurassic. It formed as a postrift regional sag as the earlier Triassic fault-controlled Mitu rifts yoked together. The rift and transitional postrift basins were associated with a NW-striking sinistral shear zone that controlled isopachs and facies distributions and resulted in magmatism and mineralization along its trend. A distinct association of later dolomitization and MVT lead-zinc mineralization also occurs with these basin-forming shear zones. Although basaltic and andesitic extrusives are common, there is no evidence that the Pacific margin was a magmatic arc until the upper Pucará, and then only weakly developed in northern Peru. Except in the upper Pucará of northwest Peru, geochemical studies, including whole rock and trace element analyses, indicate that intercalations of volcanic material have intraplate rift affinities. The basin fill has a three-part stratigraphic subdivision, comprising lower and upper carbonate platforms with an intermediate phase of basin overdeepening and sediment starvation that resulted in a regional, organic-rich argillaceous drape. Stratigraphic accumulation was dominated by axial patterns of onlap and progradation, though facies characteristics show it was augmented by periodic flooding of the western basin margin high. Marine invertebrate fossils indicate normal marine salinities. The sedimentological interpretation is based on a SW-NE transect in the southern part of the Pucará Basin. The Chambará (Norian-Rhaetian) and Condorsinga (Toarcian) formations were constructed principally by shallow-water carbonate sedimentation in lagoon-like subtidal, intertidal, and supratidal paleoenvironments. The subtidal carbonate platform is dominated by oolitic grainstones with subordinate bioclastic packstones. Subordinate open-basin facies in the Chambará Formation consist principally of crinoidal

  1. Comparison of the triple-point temperatures of 20Ne, 22Ne and normal Ne

    NASA Astrophysics Data System (ADS)

    Nakano, T.; Tamura, O.; Nagao, K.

    2013-09-01

    At the National Metrology Institute of Japan (NMIJ), the triple points of 20Ne and 22Ne were realized using modular sealed cells, Ec3Ne20 and Ec8Ne22, made by the Istituto Nazionale di Ricerca Metrologica (INRiM) in Italy. The difference of the triple-point temperatures of 20Ne and 22Ne was estimated by using the sub-range of standard platinum resistance thermometers (SPRTs) calibrated by NMIJ on the International Temperature Scale of 1990 (ITS-90). The melting curves obtained with the Ec3Ne20 and Ec8Ne22 cells show narrow widths (0.1 mK) over a wide range of the inverse of the melted fraction (1/F) from 1/F=1 to 1/F=10. The liquidus point Ttp estimated by the melting curves from F˜0.5 to F˜0.85 using the Ec8Ne22 is 0.146 29 (4) K higher than that using the Ec3Ne20 cell, which is in good agreement with that observed by INRiM using the same cells. After correction of the effect of impurities and other isotopes for Ec3Ne20 and Ec8Ne22 cells, the difference of Ttp between pure 20Ne and pure 22Ne is estimated to be 0.146 61 (4) K, which is consistent with the recent results reported elsewhere. The sub-ranges of SPRTs computed by using the triple point of 20Ne or 22Ne realized by the Ec3Ne20 cell or the Ec8Ne22 cell in place of the triple point of Ne for the defining fixed point of the ITS-90 are in good agreement with those realized on the basis of the ITS-90 at NMIJ within 0.03 mK, which is much smaller than the non-uniqueness and the sub-range inconsistency of SPRTs.

  2. Episodic yo-yo movements (epeirogeny) on continental platform intracratonic basins: Need for reinterpretation of paleogeography, faunal extinctions, and source rock maturity

    SciTech Connect

    Friedman, G.M. )

    1989-08-01

    In the Appalachian basin and Mississippi Valley, dates for epeirogeny cluster between 250 and 300 Ma, with the completion of the uplifts at about the Permian-Triassic boundary. In the Fennoscandian shield and elsewhere, uplifts appear to be of comparable age. This was the time when the continents had collided to become supercontinent Pangea which, as a result of uplift, stood high above sea level; environments became stressful, weather patterns changed, and faunal extinctions occurred. Large-scale epeirogeny began again at about 100 Ma, with some dates at about 60 Ma marking Cretaceous-Tertiary boundary extinctions. Precambrian basements, such as the Adirondacks, the Canadian shield, and the Arabo-Nubian shield suffered domal uplift during the Oligocene-Miocene, especially in the Miocene to Holocene interval. Oceanic sedimentation rates were elevated in the Miocene to accommodate this increased continental erosion. Active Holocene uplift in the Arabo-Nubian shield involving several meters or even tens of meters occurred as recently as between 3,405 {plus minus} 90 years and 2,465 {plus minus} 155 years ago.

  3. Context view from NE ridge of Daybreak Canyon running NE ...

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

    Context view from NE ridge of Daybreak Canyon running NE from lookout tower shows fire line on right and NE side of lookout tower in the far distance. Tree in foreground is Pondaross Pine that survived fires of 1991 and 1994. Camera is pointed SW with wide-angle lens. - Chelan Butte Lookout, Summit of Chelan Butte, Chelan, Chelan County, WA

  4. Lysimeter Platform

    NASA Astrophysics Data System (ADS)

    Klammler, Gernot; Murer, Erwin; Plieschnegger, Markus

    2014-05-01

    The existing European Lysimeter Platform (www.lysimeter.at/HP_EuLP) provides an overview of lysimeter types used in Europe and show details on equipment, research results and future perspectives of lysimeter facilities. However, this platform is not user-editable and has not been updated since 2008. Thus, the Lysimeter Research Group (www.lysimeter.at) intends to serve a new database based website called Lysimeter Platform, where existing information of the former European Lysimeter Platform will be transferred to the new Lysimeter Platform and, furthermore, registered users are able to create and edit sites where lysimeters, soil water samplers and soil hydrologic measuring profiles are operated. The Lysimeter Research Group is a scientific association and, therefore, the membership is free of charge. The new Lysimeter Platform contains general information of lysimeter sites worldwide (e.g., what is measured at which site) in a standardized form to get a quick but informative overview of the sites and can be linked to more detailed, already existing information provided by the site operators. Due to the standardized information in the database the Lysimeter Platform serves also as search-engine for soil water measurements and helps to find sites of interest and corresponding contact information worldwide. The Session "Estimation of soil-atmosphere and vadose zone water fluxes by use of precision lysimeter measurements" at the EGU General Assembly 2014 would be an excellent chance to present the idea and the concept of this new Lysimeter Platform to international site operators and scientists.

  5. Seismic tomographic evidence for upwelling mantle plume in NE China

    NASA Astrophysics Data System (ADS)

    He, Chuansong; Santosh, M.

    2016-05-01

    In this study, we collected teleseismic data recorded by permanent and mobile seismic stations and carried out a teleseismic P-wave tomographic study. The results reveal low velocity perturbation regions at the central part of NE China and specifically in the Songliao basin at different depths, which correspond to the location of a proposed upwelling mantle plume identified by receiver function in a recent study. Receiver function data show a predominantly mafic/ultra-mafic lower crust in the Songliao basin, in contrast to the predominantly felsic lower crust in the other regions. The vestige of upwelling mantle plume is well defined at the mantle transition region. Based on the above results, we suggest that the volcanism in NE China and the Songliao basin formation might be related to Mesozoic mantle plume beneath NE China. We also evaluate alternate models on lower crustal delamination contributing to the volcanism in NE China following collision and amalgamation between the Siberia craton and the North China-Mongolian block during late Jurassic and early Cretaceous.

  6. Regional Mesozoic basin development along the Irish continental margins: evidence from regional gravity studies

    NASA Astrophysics Data System (ADS)

    O'Reilly, B. M.; Readman, P. W.

    2003-04-01

    Sedimentary basins, which formed in response to multiphase rifting episodes during the early to late Mesozoic Era, comprise a global assemblage distributed across the entire North Atlantic region from eastern North America to the European Platform. This assemblage of basins has as its centre the region around and to the west of Ireland where tectonic re-activation of a strong NE-SW trending Caledonian basement fabric partly controlled the siting of the basins. The development of individual basins was contemporaneous with the onset of sea-floor-spreading within the Atlantic south of the Charlie Gibbs and Azores Fracture Zones. In this study a compilation of marine and satellite gravity data is primarily used to produce a regional interpretation of the tectonic fabrics in the region. A series of gravity models across the various sedimentary basins including the Rockall Basin, the Porcupine Basin and the Celtic and Irish Sea basins are used with vertical incidence and wide-angle seismic data to define crustal structure and its relationship with basin geometries. Two end-member sedimentary basin types are recognized in a regional preliminary model for Mesozoic basin development. The deep-water Rockall and Porcupine basins overlie North Atlantic lithosphere where large amounts of extensional strain were focused into the upper and mid-crust producing large amounts of syn-rift subsidence. In the shallow water shelf sea basin areas of the Celtic and Irish Sea generally smaller strains occur equally throughout all levels of the lithosphere and is distributed across wide regions of the lower crust and mantle lithosphere. This model for basin structuring requires that the strain field varies erratically within the upper to mid-crust across the North Atlantic. These changes in the pattern of strain are accommodated by rotation of continental crustal blocks (about vertical axes) and also by large-scale crustal transfer fault systems that penetrate at least to a lower crustal

  7. Orogenic evolution of the External Dinarides in the NE Adriatic region: a model constrained by tectonostratigraphy of Upper Cretaceous to Paleogene carbonates

    NASA Astrophysics Data System (ADS)

    Korbar, Tvrtko

    2009-11-01

    Mesozoic to Cenozoic evolution of the central part of the Adriatic plate (External Dinarides and Adriatic foreland) is still a matter of debate. This is expressed by opposing paleogeographic models: single carbonate platform (Adriatic or Adriatic-Dinaridic) versus two carbonate platforms (Adriatic and Dinaridic) separated by the inter-platform Budva-Cukali basin. Estimates of shortening during Adria NE subduction, that resulted in the development of the Dinaric Alps, differ substantially. The single-platform model involves minor shortening achieved by folding and faulting along steep reverse faults. The two-platform model involves significant shortening achieved mainly by thrust stacking, which resulted in almost complete underthrusting of the intervening basinal deposits. Analysis of Upper Cretaceous to Paleogene stratigraphical data from both outcrops and boreholes allows regional correlation and the interpretation of major lithostratigraphic units. As a result, a few tectonostratigraphic units are recognized. The tectonostratigraphy is used as a basis for a new model on the late Mesozoic to Cenozoic evolution of the region. Generally, Adriatic and Dinaridic segments acted as major regional crustal entities of Adria. The upper portions of the sedimentary cover were differentially affected by progressive, southwestward verging thin-skinned deformations during the Paleocene to Eocene (Miocene?). The Adriatic foreland stayed out of the deformations, and is characterized predominantly by wrench and salt tectonics. The regional tectonic map shows arcuate thrust fronts of the External Dinarides. They could be a consequence of both, differential propagation of early-orogenic thin-skinned deformations over crustal fragments separated by transversal faults, and/or differential (isostatic?) movements of the fragments. The collision zone of the Adriatic and Dinaridic segments is characterized by late-orogenic (Oligocene to Miocene) thick-skinned compressional uplift

  8. Crustal and basin evolution of the southwestern Barents Sea: From Caledonian orogeny to continental breakup

    NASA Astrophysics Data System (ADS)

    Gernigon, L.; Brönner, M.; Roberts, D.; Olesen, O.; Nasuti, A.; Yamasaki, T.

    2014-04-01

    A new generation of aeromagnetic data documents the post-Caledonide rift evolution of the southwestern Barents Sea (SWBS) from the Norwegian mainland up to the continent-ocean transition. We propose a geological and tectonic scenario of the SWBS in which the Caledonian nappes and thrust sheets, well-constrained onshore, swing from a NE-SW trend onshore Norway to NW-SE/NNW-SSE across the SWBS platform area. On the Finnmark and Bjarmeland platforms, the dominant inherited magnetic basement pattern may also reflect the regional and post-Caledonian development of the late Paleozoic basins. Farther west, the pre-breakup rift system is characterized by the Loppa and Stappen Highs, which are interpreted as a series of rigid continental blocks (ribbons) poorly thinned as compared to the adjacent grabens and sag basins. As part of the complex western rift system, the Bjørnøya Basin is interpreted as a propagating system of highly thinned crust, which aborted in late Mesozoic time. This thick Cretaceous sag basin is underlain by a deep-seated high-density body, interpreted as exhumed high-grade metamorphic lower crust. The abortion of this propagating basin coincides with a migration and complete reorganization of the crustal extension toward a second necking zone defined at the level of the western volcanic sheared margin and proto-breakup axis. The abortion of the Bjørnøya Basin may be partly explained by its trend oblique to the regional, inherited, structural grain, revealed by the new aeromagnetic compilation, and by the onset of further weakening later sustained by the onset of magmatism to the west.

  9. Jurassic platform development, northwestern Gulf of Mexico

    SciTech Connect

    Moore, C.H. Jr.

    1987-05-01

    Triassic and Early Jurassic rifting set the stage for the subsequent development of carbonate platforms in the Late Jurassic. These platforms formed along the interior margins of salt basins separated from the main ancestral Gulf of Mexico by a series of positive features. A major sea level rise, after deposition of the Louann Salt (late Callovian), drowned the interior salt basins around the margins of the Gulf of Mexico, leading to an anoxic event. Organic-rich sediments of the lower Smackover were deposited as a basin-fill sequence, forming one of the major hydrocarbon source rocks of the region. As sea level rise slowed in the late Oxfordian, carbonate production began to catch up with sea level rise along the basin margins, leading to the initial development of a rimmed carbonate platform. The platform margin was marked by high-energy ooid grainstones, while crustacean pellet muds were deposited in the platform interior. A high-energy ooid-dominated platform (upper Smackover) developed in the late Oxfordian when sea level reached a standstill. During the subsequent Kimmeridgian sea level rise, a second rimmed carbonate platform, the Haynesville, was developed. During the initial rise, grainstones were deposited on the platform margin, while the interior was dominated by evaporites (Buckner) and siliciclastics. As sea level slowed and reached a standstill, the platform margin facies extended shoreward (Gilmer) and a high-energy platform, analogous to the upper Smackover, was formed. The Smackover and Haynesville platforms of the northwestern gulf show a parallel evolution in response to cyclic changes in Upper Jurassic sea level.

  10. The Pennsylvanian and Permian Oquirrh-Wood River basin

    SciTech Connect

    Geslin, J.K. . Dept. of Earth and Planetary Sciences)

    1993-04-01

    Strata of the Middle Pennsylvanian to Lower Permian Oquirrh-Wood River Basin (OWRB) lie unconformably above the Antler orogenic belt and flysch trough/starved basin in NW Utah, NE Nevada, and SC Idaho. Strata of the basin, now separated geographically by the Neogene Snake River Plain, show similar subsidence histories, identical mixed carbonate-siliciclastic sedimentary fill, and identical chert pebble conglomerate beds supplied by one or more DesMoinesian uplifts containing Lower Paleozoic strata. This conglomerate, of the lower Sun Valley Group, Snaky Canyon Formation, and parts of the Oquirrh Formation, was reworked progressively southward, to at least the Idaho-Utah border. It is present in strata as young as Virgilian. Virgilian to Leonardian rocks are ubiquitously fine-grained mixed carbonate-siliciclastic turbidites. These rocks contain cratonal, well-sorbed subarkosic and quartzose sand and silt in part derived from the Canadian Shield. This siliciclastic fraction is intimately mixed with arenaceous micritized skeletal material and peloids derived from an eastern carbonate platform represented by the Snaky Canyon Formation in east-central Idaho, an eastern facies of the Eagle Creek Member, Wood River Formation in the Boulder Mountains, and the Oquirrh Formation in the Deep Creek Mountains. Subsidence of the OWRB may have been caused by two phases (DesMoinesian and Wolfcampian to Leonardian) of crustal loading by continental margin tectonism to the west. An elevated rim separated the OWRB from coeval volcanogenic basins to the west. Earlier, Antler-age structures may have been reactivated. A new pulse of tectonism occurred in Leonardian to Guadalupian time as in most places carbonatic and phosphatic strata of the Leonardian to Guadalupian Park City and Phosphoria Formation overlie OWRB strata, with different geographic arrangement of basinal, slope, and shelf depocenters.

  11. ENSO- and PDO-modulated SST Reconstructions From the Anthropocene Into the Last 2 Millennia: Planktonic Foraminiferal Mg/Ca Evidence at Inter-annual Resolution From San Lázaro Basin (NE Pacific)

    NASA Astrophysics Data System (ADS)

    Mortyn, P.; Martinez-Boti, M. A.; Herguera, J. C.

    2008-12-01

    On inter-annual time scales, the El Niño / Southern Oscillation (ENSO) climatic phenomenon is the largest driver of change in the ocean-atmosphere system. As such, it is a primary interest to understand how modern global warming has impacted ENSO, and how the marine sedimentary archive records this linkage in the southern California Current (CC). This would allow detailed comparison against other high-resolution archives, such as corals, and an improved ability to interpret past events as potential analogs for the future of ENSO. Furthermore, such reconstructions in recent millennia are crucial, since they record pre- anthropogenic climates under interglacial (warm) boundary conditions that allow us to characterize the nature of modern influence on this system. Here we present sub-decadal reconstructions of sea surface temperature (SST), derived from the Mg/Ca ratio of the shallow-dwelling planktonic foraminifera Globigerinoides ruber. The samples come from San Lázaro Basin in the southern Baja California continental margin (25° N; 112° W), situated beneath the dynamic boundary of the cool eastern Pacific boundary CC of northern origin, and the warm subtropical water masses of southern origin. The bottom of this coastal basin (maximum depth of 540m) is bathed by oxygen-depleted waters that flow over a shallow sill at 370m. High levels of primary production and export of biogenic particles to depth ensue from strong seasonal upwelling processes during spring to early summer. This combination of high sediment production and preservation in an area very sensitive to ENSO impact allows for a high-resolution reconstruction of inter-annual climatic phenomena in this unique eastern boundary current setting. For our highest temporal detail, we examine 2 cores at interannual resolution for the past ~90 years, which we use to validate our proxy against instrumental SSTs. This variability is effectively traced by Mg/Ca in G. ruber, which has an affinity for warmer waters

  12. Registration of 'NE01643' Wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NE01643 is a hard red winter wheat (Triticum aestivum L.) cultivar developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS and released in 2007 by the developing institutions and the South Dakota Agricultural Experiment Station. NE01643 will be marketed under the na...

  13. Crustal and basin evolution of the southwestern Barents Sea: from the Caledonian orogeny to continental breakup

    NASA Astrophysics Data System (ADS)

    Gernigon, Laurent; Brönner, Marco; Roberts, David; Olesen, Odleiv

    2013-04-01

    A new generation of aeromagnetic data documents the post-Caledonian tectonic evolution of the southwestern Barents Sea (SBS) up to the continent-ocean transition. Clear evidence of reactivation of Caledonian structures controlling both, Late Palaeozoic and Mesozoic basins can be observed at the edge of the Hammerfest and Nordkapp basins where reactivated low-angle detachments are observed on seismics. Our new aeromagnetic surveys confirm most of the previous structural elements, but new features appear and illustrate the complexity of the pre-Permian tectonic and the basement architecture in the SBS. We propose an updated tectonic scenario of the SBS where the Caledonian nappes and thrust sheets, well constrained onshore, swing anticlockwise from a NE-SW trend close to the Varanger Peninsula to NW-SE across the Nordkapp Basin and the Bjarmeland Platform. On the Bjarmeland Platform, the dominant magnetic grain is clearly NNW-SSE. We show that this pattern reflects a regional pre-Permian system involving several Caledonian thrust sheets that possibly collapsed and controlled the post-Caledonian late Palaeozoic rift development of the SBS. We also consider that this model can explain the later development of the SBS. One specific case is the Bjørnøya Basin, located between the Loppa and Stappen highs which are interpreted as a series of rigid and poorly thinned continental blocks (ribbons) flanked by the Hammerfest and Bjørnøya basins and the basins of the Vestbakken volcanic province. As part of this extensive complex system, the Bjørnøya Basin is interpreted as a extensively thinned and propagating system that aborted in Late Mesozoic time. This thick, Cretaceous sag basin is characterised by a deep high-density body, interpreted as a combination of exhumed lower crust and/or potential serpentinised mantle as suggested by potential field modelling. The abortion of this propagating basin may be partly explained by its trend, which is oblique to the inherited

  14. KM3NeT

    NASA Astrophysics Data System (ADS)

    de Jong, M.

    2015-07-01

    KM3NeT is a large research infrastructure, that will consist of a network of deep-sea neutrino telescopes in the Mediterranean Sea. The main objective of KM3NeT is the discovery and subsequent observation of high-energy neutrino sources in the Universe. A further physics perspective is the measurement of the mass hierarchy of neutrinos. A corresponding study, ORCA, is ongoing within KM3NeT. A cost effective technology for (very) large water Cherenkov detectors has been developed based on a new generation of low price 3-inch photo-multiplier tubes. Following the successful deployment and operation of two prototypes, the construction of the KM3NeT research infrastructure has started. The prospects of the different phases of the implementation of KM3NeT are summarised.

  15. KM3NeT

    SciTech Connect

    Jong, M. de; Collaboration: KM3NeT Collaboration

    2015-07-15

    KM3NeT is a large research infrastructure, that will consist of a network of deep-sea neutrino telescopes in the Mediterranean Sea. The main objective of KM3NeT is the discovery and subsequent observation of high-energy neutrino sources in the Universe. A further physics perspective is the measurement of the mass hierarchy of neutrinos. A corresponding study, ORCA, is ongoing within KM3NeT. A cost effective technology for (very) large water Cherenkov detectors has been developed based on a new generation of low price 3-inch photo-multiplier tubes. Following the successful deployment and operation of two prototypes, the construction of the KM3NeT research infrastructure has started. The prospects of the different phases of the implementation of KM3NeT are summarised.

  16. Integrated diagenetic and sequence stratigraphy of a late Oligocene-early Miocene, mixed-sediment platform (Austral Basin, southern Patagonia): Resolving base-level and paleoceanographic changes, and paleoaquifer characteristics

    NASA Astrophysics Data System (ADS)

    Dix, George R.; Parras, Ana

    2014-06-01

    A condensed (~ 20-m-thick) marine transgressive-highstand succession comprises the upper San Julián Formation (upper Oligocene-lower Miocene) of the northern retroarc Austral Basin, southern Patagonia. Mixed-sediment facies identify a shelf-interior setting, part of an overall warm-temperate regional platform of moderate energy. Giant oyster-dominated skeletal-hiatal accumulations along the maximum flooding surface and forming high-energy event beds in the highstand succession preserve relict micrite in protected shelter porosity, and identify periods of reduced sediment accumulation. The stratigraphic distribution of marine-derived glaucony and diagenetic carbonates is spatially related to sequence development. Depositional siderite coincides with prominent marine transgression, defining transient mixing of marine and meteoric waters across coastal-plain deposits. Chemically evolved autochthonous glaucony coincides with periods of extended seafloor exposure and transgressions that bracket the marine succession, and within the oyster-dominated skeletal accumulations. Seafloor cement, likely once magnesian calcite, formed in association with an encrusting/boring biota along the maximum flooding surface in concert with incursion of cool (11-13 °C) water. The cement is present locally in skeletal event beds in the highstand succession suggesting a possible association with high-order base-level change and cooler water. As the highstand succession coincides with elevated global sea level in the late Oligocene-early Miocene, the locally marine-cemented glauconitic skeletal event beds in the highstand succession may identify higher order glacio-eustatic control. Local stratal condensation, however, is best explained by regional differences in basement subsidence. In the burial realm, carbonate diagenesis produced layers of phreatic calcrete coincident with skeletal-rich deposits. Zeolite (clinoptilolite-K) cement is restricted to the lowermost marine transgressive

  17. Polyphase evolution of the Chaîne des Matheux frontal thrust (Haiti)

    NASA Astrophysics Data System (ADS)

    Wessels, Richard; Ellouz-Zimmermann, Nadine; Rosenberg, Claudio; Bellahsen, Nicolas; Hamon, Youri; Deschamps, Remy; Battani, Anne; Leroy, Sylvie; Momplaisir, Roberte

    2016-04-01

    The NW - SE trending Haitian fold-and-thrust belt (HFTB) is located in the western part of the Caribbean island of Hispaniola. It covers the suture between the Cretaceous Caribbean island arc in the north and the Late Cretaceous thickened oceanic crust in the south. The HFTB is bounded to the north and south by the left-lateral Septentrional (SFZ) and Enriquillo-Plantain Garden (EPGFZ) fault zones, respectively. Compressional deformation on the HFTB commenced as early as Eocene times. It was followed by transpressional deformation from the early Miocene onwards, with in sequence progressive stacking of thrust sheets towards the SW. Seismicity at the junction between the HFTB and the EPGFZ is recorded by the 12 January 2010 Mw 7.0 earthquake. Surface mapping did not reveal a rupture, as the main activity occurred on the steep NNW dipping oblique transpressional Léogâne fault, while aftershocks documented motion on a shallow SW dipping thrust segment. The structural style of deformation of the HFTB, either the stacking of thrust sheets on basement heterogeneities or basement-involved thrusting, has not been studied in detail. Also lacking are conceptual models addressing the amount of convergence between the northern and southern domains, and describing how convergence was accommodated. To address these problems we conducted a detailed fieldwork on the southernmost thrust sheet, known as the Chaîne des Matheux front. Using stratigraphy, geological mapping, cross sections, kinematic fault slip data, analysis of mineralizations and fluid inclusions, and geochemical analysis of fluid seeps, we decipher the evolution of this anticlinal structure. Stratigraphic data reveal stable Eocene platform sedimentation over the whole region, which preceded deepening of the basin throughout Oligocene and early Miocene times. A diachronous evolution is evident from the middle Miocene onwards. The NE flank displays a shallowing upwards trend and clastic sedimentation, while the

  18. Isostatic controls on carbonate platform development

    SciTech Connect

    Aigner, T.; Doyle, M.; Lawrence, D.T.

    1987-05-01

    Although carbonate bodies represent a significant surface load on the lithosphere, isostatic effects have been little studied in carbonate systems. In addition to well-documented controls such as spatially varying growth potential, the isostatic response to carbonate platform loads can be an important control on a variety of large-scale patterns in carbonate platform evolution. (1) The bucket structure as the basic anatomy of carbonate platforms can be explained isostatically by load-induced sagging of platform interiors and upbulging of platform margins. (2) Pulses of rapid sea level rises may transform isostatically sagged platform interiors into partly drowned intra-platform basins surrounded by elevated rims. (3) Differential drowning of isostatically sagged platforms may cause a wide-spread megabank to evolve into an archipelago of isolated platforms and intervening troughs. This may be an alternative mechanism for the origin of isolated platforms in the Bahamas. (4) Isolated pinnacle reefs within carbonate/evaporite provinces that occur close to the shelf margin may be initiated in flexural bulges developing beyond the edges of the load of the carbonate shelf during a cycle of sea level fall and rise. Quantitative computer simulations of the isostatic control on carbonate platform development will be presented.

  19. 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.

  20. Estimation of the extraterrestrial 3He and 20Ne fluxes on Earth from He and Ne systematics in marine sediments

    NASA Astrophysics Data System (ADS)

    Chavrit, Déborah; Moreira, Manuel; Moynier, Frédéric

    2016-04-01

    Sediments contain interplanetary dust particles (IDPs) carrying extraterrestrial noble gases, such as 3He, which have previously been used to estimate the IDP accretion flux over time and the duration of past environmental events. However, due to its high diffusivity, He can be lost by diffusion either due to frictional heating during entry in the atmosphere, or once it has been incorporated in the sediments. Therefore the absolute values of 3He IDP fluxes cannot be known. Due to its lower diffusivity, Ne is less likely to be lost by diffusion than He and can potentially provide an absolute IDP flux value. Here, we studied the Ne and He isotopic composition of 21 sediments of different ages (3 to 38 Myr, 56 Myr and 183 Myr) in order to better constrain the retention of 3He in such deposits. The samples are carbonates from 2 sites of the Integrated Ocean Drilling Program (IODP), which previously showed evidence of detectable extraterrestrial 3He, and from the Sancerre core in the Paris basin. The 3He/4He, 20Ne/22Ne and 21Ne/22Ne ratios of decarbonated residues vary respectively from 0.09×10‑6 to 76.5×10‑6, 9.54±0.08 to 11.30±0.60 and from 0.0295±0.0001 to 0.0344±0.0003. These isotopic compositions can be explained by a mixing between two terrestrial components (atmosphere and radiogenic He and nucleogenic Ne present in the terrigenous fractions) and an extraterrestrial component. The linear relationship between 20Ne/22Ne and 3He/22Ne ratios shows that the extraterrestrial component has a unique composition and is similar to the He and Ne composition of implanted solar wind. This composition is different from the individual stratospheric IDPs for which the Ne and He isotopic compositions have been measured. We suggest that this difference is due to a bias in the sampling of the individual IDPs previously analyzed toward the largest ones that are more likely to lose He during entry in the atmosphere. Our data further constrains the size of the majority of

  1. Estimation of the extraterrestrial 3He and 20Ne fluxes on Earth from He and Ne systematics in marine sediments

    NASA Astrophysics Data System (ADS)

    Chavrit, Déborah; Moreira, Manuel A.; Moynier, Frédéric

    2016-02-01

    Sediments contain interplanetary dust particles (IDPs) carrying extraterrestrial noble gases, such as 3He, which have previously been used to estimate the IDP accretion flux over time and the duration of past environmental events. However, due to its high diffusivity, He can be lost by diffusion either due to frictional heating during entry in the atmosphere, or once it has been incorporated in the sediments. Therefore the absolute values of 3He IDP fluxes cannot be known. Due to its lower diffusivity, Ne is less likely to be lost by diffusion than He and can potentially provide an absolute IDP flux value. Here, we studied the Ne and He isotopic composition of 21 sediments of different ages (3 to 38 Myr, 56 Myr and 183 Myr) in order to better constrain the retention of 3He in such deposits. The samples are carbonates from 2 sites of the Integrated Ocean Drilling Program (IODP), which previously showed evidence of detectable extraterrestrial 3He, and from the Sancerre core in the Paris basin. The 3He/4He, 20Ne/22Ne and 21Ne/22Ne ratios of decarbonated residues vary respectively from 0.09 ×10-6 to 76.5 ×10-6, 9.54 ± 0.08 to 11.30 ± 0.60 and from 0.0295 ± 0.0001 to 0.0344 ± 0.0003. These isotopic compositions can be explained by a mixing between two terrestrial components (atmosphere and radiogenic He and nucleogenic Ne present in the terrigenous fractions) and an extraterrestrial component. The linear relationship between 20Ne/22Ne and 3He/22Ne ratios shows that the extraterrestrial component has a unique composition and is similar to the He and Ne composition of implanted solar wind. This composition is different from the individual stratospheric IDPs for which the Ne and He isotopic compositions have been measured. We suggest that this difference is due to a bias in the sampling of the individual IDPs previously analyzed toward the largest ones that are more likely to lose He during entry in the atmosphere. Our data further constrains the size of the majority

  2. Reply to the comment by Boulila and Hinnov towards "Chronology of the Early Toarcian environmental crisis in the Lorraine Sub-Basin (NE Paris Basin)" by W. Ruebsam, P. Münzberger, and L. Schwark [Earth and Planetary Science Letters 404 (2014) 273-282

    NASA Astrophysics Data System (ADS)

    Ruebsam, Wolfgang; Münzberger, Petra; Schwark, Lorenz

    2015-04-01

    Recently Boulila and Hinnov provided an alternative interpretation for the cyclostratigraphy of the Early Toarcian in the Lorraine Basin proposed by Ruebsam et al. (2014). Floating chronologies based on cyclostratigraphy, in particular when discrete time lines (e.g. tephra layers, intrusions, etc.) are missing, are subject to contrasting interpretation and discussion as exemplified for the Early Toarcian by previous contributions (e.g. Kemp et al., 2011; Boulila et al., 2014; Huang and Hesselbo, 2014). In the following we address the discussion raised by Boulila and Hinnov with specific focus on differential sedimentation rates in sub-basins on the NW-Tethyan Shelf during the Early Toarcian and how this may have affected i) the duration of individual ammonite (sub)zones and the Toarcian carbon isotopic excursion, ii) the expression of a 405 ka cycle and iii) the obliquity-forcing on paleoclimate.

  3. (U-Th)/Ne Chronometry

    NASA Astrophysics Data System (ADS)

    Gautheron, C. E.; Tassan-Got, L.; Farley, K. A.

    2005-12-01

    Nuclear production of 21Ne, like 4He, in U and Th rich minerals such as apatite, zircon, monazite and titanite can potentially be used for chronometry. Due to the absence of 24Mg from the accessory minerals of interest, the production of 21Ne through neutron-induced reactions can be neglected and this production only occurs through the reaction 18O(α,n)21Ne. As the closure temperature is higher for neon than for helium, this gives a possible insight to the thermal history of minerals. To test the possibility of this new chronometer, a review of the available cross section data has been done, permitting a reevaluation of the 21Ne production from this reaction, using a thin target approach and testing the validity of the results against thick target situations. The important factors of the simulation are the cross section and the stopping distance values for a mineral characterized by its chemical composition and density. The (21Ne/4He) production ratio in these minerals is about 4× 10-8, but varies with oxygen content and Th/U ratio. Although the 21Ne has a stopping range of about 1 μm compared to about 20 μm for α particles, preferential α ejection compared to 21Ne lowers (21Ne/4He) at grain edges. For a bulk crystal the (21Ne/4He) production ratio depends on crystal size when the crystals are small. Using a Monte Carlo model we computed the effects of ejection on the (21Ne/4He) ratio for various geometries and grain sizes. The simulation can be run by any user through a graphical interface accessible from the Web at the address: http://h0.web.u-psud.fr/UThHeNe_MonteCarloSimulation/. We also present measurements of the (21Ne/4He) ratio on few mg aliquots of well-dated volcanic apatites and zircons. Values of (4.43± 1.1)× 10-8 and (3.46± 1.2)× 10-8 for apatite and zircon respectively are in agreement with the theoretical values of (4.16± 0.14)× 10-8; (3.54± 0.13)× 10-8. Based on our production rate estimates the Durango apatite and Fish Canyon Tuff

  4. Shear-wave splitting within the Southeastern Carpathian Arc, Transylvanian Basin, Romania

    NASA Astrophysics Data System (ADS)

    Stanciu, A. C.; Russo, R. M.; Mocanu, V. I.; Munteanu, L.

    2013-10-01

    We present new splitting measurements for SKS and SKKS phases recorded at four broadband seismic stations located within the Carpathian Arc, in the eastern part of the Transylvanian Basin. We made 75 measurements, of which 58 are nulls and 17 show clear splitting. We used two methods to estimate splitting parameters, ϕ (the fast polarization direction) and δt (the delay time between fast and slow split shear waves): minimization of energy on the horizontal component corresponding to the minimum eigenvalue of the polarization matrix, and simultaneous linearization of split waves from a suite of earthquakes recorded at a given station. We consistently observed no splitting at station IACB, in the northern part of the study area, for a range of well-recorded earthquakes at different backazimuths; we consider the station splitting to be null. Null splitting here is consistent with several possible tectonic scenarios, including downwelling of asthenospheric material as a result of the sinking Vrancea body, asthenospheric upwelling beneath Ciomadul volcano, or lack of anisotropic fabric development in the large Ciomadul magma chamber beneath the station. Fast polarized shear waves trend NW-SE at CHDM, in the Transylvanian Basin, and at PMAR, which lies at the boundary between the Transylvanian Basin and the E-W-striking Southern Carpathians; these fast directions are consistent with a regional trend in splitting ϕ azimuths over much of the Eastern Carpathians, the East European and Moesian Platforms, and the northwestern Transylvanian Basin away from the Vrancea Bend Zone. The regional NW-SE splitting trend parallels the NW-to-SE temporal migration of Neogene volcanism along the Eastern Carpathians, and is likely due to a combination of southeastward rollback of the Vrancea high velocity body and simultaneous southwestwards absolute plate motion of the thick leading edge of the East European Platform (Tornquist-Teisseyre Suture Zone), which together constrain regional

  5. Structure of thinned continental crust across the Orphan Basin from a dense wide-angle seismic profile and gravity data

    NASA Astrophysics Data System (ADS)

    Lau, K. W. Helen; Watremez, Louise; Louden, Keith E.; Nedimovíć, Mladen R.

    2015-09-01

    We present a 500-km long, 2-D P-wave velocity model across the Orphan Basin, offshore NE Newfoundland, Canada, from Flemish Cap to the Bonavista Platform, formed using refraction and wide-angle reflection data from 89 ocean-bottom seismometers. This layered model builds on a recent traveltime tomography result using additional constraints from coincident multichannel seismic reflection and gravity data plus borehole logs from three wells. The model shows (i) post-rift Tertiary (velocities ˜1.7-3.5 km s-1) and (ii) both post-rift and syn-rift, Cretaceous and Jurassic sediments (˜4-5 km s-1), deposited within an eastern and a western sub-basin that are separated by a major basement block. The existence of Jurassic sediments indicates a pre-Cretaceous rifting phase in the eastern sub-basin, and possibly in the western sub-basin. However, there is no evidence that Triassic sediments are widespread across the Orphan Basin. Two upper crustal sublayers and one lower crustal layer are defined by differences in velocities (5.4-6.1, 6.1-6.5 and 6.3-7.1 km s-1, respectively) and vertical velocity gradients (mean = 0.14, 0.10 and 0.05 s-1, respectively). Crustal thinning is asymmetric across the Orphan Basin. Within the eastern sub-basin, continental crust beneath Flemish Cap (˜32 km thick; β ˜ 1.1) thins westward into a 35-km-wide zone of hyperextended crust (<10 km thick; β > 3.4) beneath an 11-km-deep sedimentary basin. Within the western sub-basin, the Bonavista Platform crust (˜32 km thick) thins eastward into a 116-km-wide zone of hyperextended crust. Two zones of thicker crust (β = 2-3.5) exist within the central section, with muted topography within the eastern part and large basement highs in the western part, separated by the eastward dipping White Sail Fault (WSF). The zone to the east of the WSF displays higher velocities in the lower crust than to the west. This can only be explained by a lateral ductile flow across the zone boundary. By combining the two

  6. Stress Map 2.0: Updating the Stress Map of the Western Canadian Sedimentary Basin

    NASA Astrophysics Data System (ADS)

    Mallyon, D.; Schmitt, D. R.; Currie, C. A.; Gu, Y. J.; Heidbach, O.

    2015-12-01

    The greatest horizontal compression in much of the Western Canada Sedimentary Basin appears to uniformly trend NE-SW. Beyond this, major gaps remain in our knowledge of stress magnitudes and even faulting regimes. This lack of quantitative information impedes a proper understanding of seismic events that appear to be linked to hydraulic fracturing stimulations. Apart from this immediate concern, such seismicity could impact long term green-house gas sequestration and geothermal energy development. As part of the Helmholtz-Alberta geothermal collaboration, we are developing a program to update this crustal stress state information. The program consists of more immediate studies related to conventional analysis of borehole image logs, core fractures, and transient pressure records as can be made available. Data sets analyzed to date include logs to 3.5 km depth from areas experiencing induced seismicity, from 2.5 km depth within the Precambrian craton in NE Alberta, and to 400 m depth within a large carbonate platform. All these data largely confirm the NE-SW stress directions. In some cases, the configurations of drilling induced tensile fractures and borehole breakouts allow the faulting regime to be constrained. The addition of new seismometers to the region is also allowing for the refinement of earthquake focal mechanisms. Finally, a dramatic contrast in lithosphere thickness, composition and geothermal gradient exists at the contact between the Cordillera and the North American craton; therefore, lithosphere-scale numerical models are also being developed to quantify the relative contribution of geodynamic processes, such as mantle flow and contact geometry, to the observed stress regime within the basin.

  7. Collapse of modern carbonate platform margins

    SciTech Connect

    Mullins, H.T.; Hine, A.C.; Gardulski, A.

    1985-01-01

    Modern carbonate platform margins in the Florida-Bahama region have been viewed as depositional or constructional features. However, recent studies have shown that carbonate escarpments, such as the Blake-Bahama and West Florida Escarpments, are erosional in origin where the platform margins have a scalloped or horse-shoe shape. Seismic reflection data from one of these crescentic features along the west Florida platform margin indicate that it originated by large scale gravity collapse (slump). This collapse structure extends for at least 120 km along the margin and has removed about 350 m of strata as young as early Neogene. Although at least three generations of slope failure are recognized, catastrophic collapse appears to have occurred in the mid-Miocene. Gravitational instability due to high rates of sediment accumulation may have been the triggering mechanism. These data suggest that submarine slumping is an important process in the retreat of limestone escarpments and in the generation of carbonate megabreccia debris flows. Scalloped platform margins occur on satellite images of northern Exuma Sound and Columbus Basin in the Bahamas. The authors suggest that large-scale submarine slumping can cause elongation of structurally controlled intraplatform basins (Exuma South), and produce anomalous horse-shoe shaped basins (Columbus Basin) by mega-collapse processes.

  8. Fluvial drainage systems: Margaritifer Sinus and Agyre (NC, NE) quadrangles, Mars

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    Fluvial drainage systems, delineated by mapping on stereo pairs of Viking Orbiter images, have developed in various-sized basins in the Margaritifer Sinus (MC-19) and Agyre (MC-26) Quadrangles, Mars. The Ladon Valles system is the largest, draining into and through two multi-ringed impact basins. Smaller fluvial basins to the southeast of the Ladon structural basin appear to have internal drainage. An intermediate-scale fluvial basin containing Himera Vallis extends along a north-south axis at 22 W and opens northward toward outflow channels south of Margaritifer Chaos. Stereo-pair mapping was extended furhter to the east, in MC-19 Ne, Se, and MC-26 NE, to investigate sources of outflow to the Ares Vallis system. The direction of flow in the channel at the northeast quadrant of the Ladon Basin is unresolved at present because of the poor quality of images available to form stereo pairs. However, an easterly drainage basin boundary running north-south along longitude 9 W, and extending westward at latitude 32-35 S, encloses a series of longitudinal drainage systems. Both the Parana Valles-Loire Vallis system and the Samara Valles system appear to drain in a northwesterly direction. The Samara flows to the Himera drainage basin, and the Parana-Loire to the northeast Ladon channel area.

  9. Neogene-Quaternary evolution of the Tefenni basin on the Fethiye-Burdur fault zone, SW Anatolia-Turkey

    NASA Astrophysics Data System (ADS)

    Aksoy, Rahmi; Aksarı, Süleyman

    2016-06-01

    The Fethiye-Burdur fault zone (FBFZ) is a complex belt of major break in the southwestern Anatolia. A number of basins occur within the FBFZ. The Tefenni basin is one of the NE-SW trending basins located in the central part of the FBFZ. The basin is 10-20 km wide and 60 km long. It contains two infills of fluvial, lacustrine and alluvial fan deposits from late Miocene to Recent. The older and folded infill rests on the pre-middle Miocene basement rocks with an angular unconformity and consists of fluvial and lacustrine sediments. The younger and undeformed Plio-Quaternary basin fill unconformably overlies the older basin fill and is composed predominantly of conglomerate, mudstone, silt, clay and recent basin floor sediments. The Tefenni basin is controlled by a series of NE-SW trending left lateral oblique-slip normal faults along its margins. The Tefenni and Mürseller faults bound the northwestern margin of the basin and the Kemer fault bounds the southeastern margin of the basin. The basin is also cut by NE-SW striking major and NW-SE, N-S and E-W striking small scale normal faults. Structural analyses in the basin show that NE-SW-trending contraction stress regime ended by Pliocene and was followed by NE-SW-trending extension from Pliocene onward.

  10. KInNeSS: a modular framework for computational neuroscience.

    PubMed

    Versace, Massimiliano; Ames, Heather; Léveillé, Jasmin; Fortenberry, Bret; Gorchetchnikov, Anatoli

    2008-01-01

    Making use of very detailed neurophysiological, anatomical, and behavioral data to build biologically-realistic computational models of animal behavior is often a difficult task. Until recently, many software packages have tried to resolve this mismatched granularity with different approaches. This paper presents KInNeSS, the KDE Integrated NeuroSimulation Software environment, as an alternative solution to bridge the gap between data and model behavior. This open source neural simulation software package provides an expandable framework incorporating features such as ease of use, scalability, an XML based schema, and multiple levels of granularity within a modern object oriented programming design. KInNeSS is best suited to simulate networks of hundreds to thousands of branched multi-compartmental neurons with biophysical properties such as membrane potential, voltage-gated and ligand-gated channels, the presence of gap junctions or ionic diffusion, neuromodulation channel gating, the mechanism for habituative or depressive synapses, axonal delays, and synaptic plasticity. KInNeSS outputs include compartment membrane voltage, spikes, local-field potentials, and current source densities, as well as visualization of the behavior of a simulated agent. An explanation of the modeling philosophy and plug-in development is also presented. Further development of KInNeSS is ongoing with the ultimate goal of creating a modular framework that will help researchers across different disciplines to effectively collaborate using a modern neural simulation platform. PMID:18695948

  11. Middle Miocene mound-shaped sediment packages on the slope of the Xisha carbonate platforms, South China Sea: Combined result of gravity flow and bottom current

    NASA Astrophysics Data System (ADS)

    Tian, Jie; Wu, Shiguo; Lv, Fuliang; Wang, Dawei; Wang, Bin; Zhang, Xinyuan; Ma, Benjun

    2015-12-01

    Deep-water mound-shaped sediment packages on the northern slope of the Xisha carbonate platforms in the northern South China Sea were analyzed by integrating high-resolution multi-channel seismic and drilling data. The mounds are distributed in the Beijiao depression of the Qiongdongnan Basin within the T41-T40 seismic horizons, which correspond to the middle Miocene. Mound-shaped reflections were identified both in the NE-SW and NW-SE oriented seismic profiles. The mound shapes are most prominent in the center of the NW-SE oriented seismic profiles, and the undulating tops flatten out towards the NW and SE. Similar reflections are mostly asymmetric, with steeper eastern flanks in the NE-SW oriented seismic profiles, and they are mostly round in shape. The wave impedance from the inversion calculation is 6-8×106 kg/(m2·s). It is much lower than that of the reef reservoir in the LH11-1 Reef Oilfield. Paleogeographic analysis shows that the Xisha uplift was dominated by tropical shallow carbonate platforms, while the Beijiao depression became a bathyal environment in the middle Miocene. Drilling data confirmed that the mound-shaped sediment packages are mainly composed of calcareous mudstone. Therefore, we infer that the mound-shaped sediment packages could be reef complexes or they were presumably built by combined gravity flow and bottom current.

  12. Active faults and minor plates in NE Asia

    NASA Astrophysics Data System (ADS)

    Kozhurin, Andrey I.; Zelenin, Egor A.

    2014-05-01

    portion of the plate northern boundary. With this, we have discovered no active faults or fault zones of the Ulakhan fault strike, which could be the portion of the boundary between the Lankovaya-Omolon zone and either the western margin of the Komandor basin or the westernmost Aleutians. We conclude that there is a certain disagreement between active faulting pattern and plate models for NE Asia, relating to the extent of the plates and missing portions of the plate boundaries. The research was supported by grant # 110500136-a from the Russian Foundation for Basic Research.

  13. Paleogene Rift Basins along East China Sea: Tectonic Evolution of Penghu Basin

    NASA Astrophysics Data System (ADS)

    Yang, Tzu-Ruei; Yang, Kenn-Ming; Kuo, Yong-Chein; Lee, Chang-Ji

    2013-04-01

    Prior to the orogeny, Taiwan is located at the passive continental margin. Two extensional events in Tertiary resulted in Paleogene and Neogene basins. The Paleogene rift basins along East China Sea and Taiwan Straight - Tungyintao, Nanjihtao, Penghu basins, from north to south, respectively, comprise a left-lateral and en echelon array rift system. Previous wellbore data revealed that these basins are filled with Paleocene and Eocence sediments, which were controlled by the NE-SW trending growth normal faults. Moreover, Penghu basin is composed of two sub-basins separated by lateral fault which induced a regional volcanic uplift. The seismic profiles indicate that it represents a typical half-graben basin with wedge-shaped synrift deposits thickening toward the main boundary fault. Five wells in the Penghu basin show that Penghu basin began to form during the Late Pliocene with shallow marine deposition. The mid-Eocene shale sequences in northwestern side are interbedded with some layers of basic lava flow, which indicate that the normal faults induced the volcanism. Data used in this study consist of: (1) multi-channel seismic data, (2) seven wellbore data acquired by CPC, Taiwan (Chinese Petroleum Corporation, Taiwan). Seismic profiles were interpreted by Kingdom Suite. Afterwards, integrate synthetic seismogram to generate depth-converted profiles, and import them to 2Dmove for cross-section restoration. Three regional unconformities and four sequence units are delineated in this area. Seismic profile interpretations also infer that the main faults dominantly oriented NE-SW, and the formation of Penghu basin is mostly due to the normal fault in the southeastern side, which is NE-SW trending in the north, and gradually changes to nearly E-W trending. These normal faults are separated by some lateral faults. Restoration of representive cross sections suggest three phases of basin development in the Penghu basin. Regarding to the stratigraphy framework according

  14. Bulk crustal properties in NE Tibet and its implication for deformation model

    NASA Astrophysics Data System (ADS)

    Tian, Xiaobo

    2014-05-01

    The crust beneath the northeastern (NE) Tibetan Plateau records far field effects of collision and convergence occurring between the Indian and Eurasian plates. A better structural understanding of the crust beneath NE Tibet can improve our understanding of Cenozoic deformation resulting from the India-Eurasia collision. Taking advantage of the relatively dense coverage in most areas in NE Tibet except for the Qaidam basin by regional seismic networks of Gansu and Qinghai Provinces, we isolate receiver functions from the teleseismic P wave data recorded from 2007 to 2009 and resolve the spatial distribution of crustal thickness and Vp/Vs ratio beneath NE Tibet from H-K scanning. Our results can be summarized as: (1) NE Tibet is characterized by ~ 60-km-thick crust beneath the Nan Shan, Qilian Shan thrust belts and the Anyemaqen Shan, and 45-50 km-thick crust beneath the Tarim basin, the Alashan depression and the Ordos basin; the crust thins gradually from west to east in addition to the previously observed pronounced thinning from south to north; (2) the crust of NE Tibet exhibits a relatively lower Vp/Vs ratio of 1.72 than the north China block and a decrease in average crustal Vp/Vs ratio with increasing crustal thickness; and (3) the crustal thicknesses are less than the values predicted by the simple isostatic model of throughout Tibetan plateau in where the elevation is larger than 3.0 km. Our observations can be explained by the hypothesis that deformation occurring in NE Tibet is predominated by upper-crustal thickening or lower-crust extrusion.

  15. "Normal Planetary" Ne-Q in Chelyabinsk and Mars

    NASA Astrophysics Data System (ADS)

    Nyquist, L. E.; Park, J.; Nagao, K.; Haba, M. K.; Mikouchi, T.; Kusakabe, M.; Shih, C.-Y.; Herzog, G. F.

    2015-07-01

    Chelyabinsk contains “Q”-noble gases. Martian shergottite Dhofar 378 contains trapped 20Ne/22Ne = 7.3±0.3, derivable from Q-Ne with 20Ne/22Ne = 10.67 via fractionation by solar wind induced sputtering. Martian juvenile Ne is suggested to be Q-Ne.

  16. Shear-Wave Splitting Within the Southeastern Carpathian Arc, Transylvanian Basin, Romania

    NASA Astrophysics Data System (ADS)

    Stanciu, A. C.; Russo, R. M.; Mocanu, V. I.; Munteanu, L.

    2012-12-01

    We present 75 new measurements of shear wave splitting at 4 temporary broadband seismic stations that we deployed in the Transylvanian Basin within the Carpathian Arc, Romania. The Tisza-Dacia terranes, which form the basement of this basin, were accommodated in the space between the thick, old, rigid and cold East European Platform and the Moesian Platform during the Miocene. This movement was driven by the subduction of a part of the Tethys Ocean, which led to the formation of Carpathian orogen system. In Romania, the mountains are divided into the Eastern Carpathians, at the limit of Transylvanian Basin and the East European Platform along the Tornquist-Teisseyre Suture Zone, and the Southern Carpathians, at the limit with Moesian Platform. They connect to the West of the Carpathian Bend Zone where a very active high velocity seismic body generates intermediate depth earthquakes between 70 and 200 km beneath the Vrancea seismogenic zone. We analyzed splitting of SKS and SKKS phases recorded at epicentral distances between 87 and 150 degrees using the method of Silver and Chan (1991). We estimated splitting parameters, fast shear polarization azimuth and delay time, using both weighted averages of individual splitting measurements (Helffrich et al., 1994) and simultaneous linearization of all clearly recorded SK(K)S waves (Wolfe and Silver, 1998). For COMD, located at the contact of the Carpathian Bend Zone and Transylvanian Basin, we obtained a fast shear polarization azimuth trending NE-SW, parallel to the contact and to the strike of the Vrancea seismic body. For 10 suitable events recorded at IACB, at the contact of the Neogene Volcanic zone with the Eastern Carpathians, we did not observe any splitting; we consider the station splitting to be null. The fast shear polarization azimuth for PMAR, at the limit between Tisza-Dacia block and Southern Carpathians thrust belt, and at CHDM, within the Transylvanian Basin, is NW-SE similar to a regional splitting

  17. Geomorphological context of the basins of Northwestern Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Sautter, Benjamin; Pubellier, Manuel; Menier, David

    2014-05-01

    Geomorphological context of the basins of Northwestern Peninsular Malaysia Benjamin Sautter, Manuel Pubellier, David Menier Department of Petroleum Geosciences, Universiti Teknologi PETRONAS CNRS-UMR 8538, Ecole Normale Supérieure, 24, Rue Lhomond, 75231, Paris Cedex 05, France Petroleum basins of Western Malaysia are poorly known and their formation is controlled by the Tertiary stress variations applied on Mesozoic basement structures. Among these are the Paleozoic-Mesozoic Bentong Raub, Inthanon, and Nan suture zones. By the end of Mesozoic times, the arrival of Indian plate was accompanied by strike slip deformation, accommodated by several Major Faults (Sagaing, Three Pagodas, Mae Ping, Red River, Ranong and Klong Marui Faults). Due to changes in the boundary forces, these areas of weakness (faults) were reactivated during the Tertiary, leading to the opening of basins in most of Sundaland. Within this framework, while most of the Sundaland records stretching of the crust and opening of basins (SCS, Malay, Penyu, Natuna, Mergui) during the Cenozoics, Peninsular Malaysia and the Strait of Malacca are considered to be in tectonic quiescence by most of the authors. We present the geomorphology of the Northwestern Malaysia Peninsula with emphasis on the deformations onshore from the Bentong Raub Suture Zone to the Bok Bak Fault, via the Kinta Valley, and offshore from the Port Klang Graben to the North Penang Graben. By analyzing Digital Elevation Model from ASTER and SRTM data, two main directions of fractures in the granitic plutons are highlighted: NW-SE to W-E sigmoidal faults and N-S to NE-SW linear fractures which seem to cross-cut the others. In the field in the area of the Kinta Valley (Western Belt, NW Peninsular Malaysia), granitic bodies show intense fracturation reflecting several stages of deformation. The granites are generally syntectonic and do not cut fully across the Late Paleozoic platform limestone. Two sets of fractures (NW-SE and NE

  18. 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.

  19. Drowned Carbonate Platforms in the Huon Gulf, Papua New Guinea; Morphology, Composition and Implications for Reef Development on a Rapidly Subsiding Margin

    NASA Astrophysics Data System (ADS)

    Webster, J.; Silver, E.; Potts, D.; Wallace, L.; Riker-Coleman, K.; Gallup, C.; Applegate, B.; Jupiter, S.

    2002-12-01

    Collision between the South Bismarck Plate and the northern edge of the Australian Plate has produced an actively subsiding foreland basin in the western Huon Gulf. A series of drowned coral reef platforms and pinnacles are preserved on this margin as a result of this rapid subsidence. Previous data and models suggest that these platforms drowned due to the combined affects of rapid relative sea-level rise associated with glacial terminations and continual subsidence (up to 5.7 mm/year) over the last 400 ky. A multidisciplinary cruise on the R/V Melville (Aug-Sep 2001). mapped and sampled nine platforms and pinnacles using; (1) Seabeam 2000; (2) high-resolution side-scan mapping (DSL120) and (3) the ROV Jason for outcrop sampling. Two U-Th ages (348 ka at 1950 mbsl and 60 ka at 240 mbsl) confirm the platforms age and deepen progressively NE towards the Markham Fault. The bathymetric and sidescan data indicates the platforms are composite features, often recording multiple terrace levels and pinnacle structures that probably formed during less dramatic interstadial sea-level fluctuations. The edges of the platforms have experienced substantial lateral modification through fracturing and slumping, producing vertical outcrop exposures, slumped blocks and debris fields. However, the tops of each platform appear to preserve the signature and timing of platform drowning. Coral assemblages and microfacies data indicate there are significant differences in paleoenvironmental settings between the shallow, middle and deep platforms. Prior to drowning, the deeper platforms developed in significantly higher energy reefal conditions compared with the middle or shallow platforms. Thus the paleoenvironmentals conditions have changed substantially through time in the Huon Gulf. The changes may be related a re-organisation of the oceanographic/climatic conditions of the Huon Gulf as a result of; (1) the rotation and uplift of the Huon Peninsular and/or (2) variation in more

  20. Response of the Rhône deltaic margin to loading and subsidence during the last climatic cycle

    NASA Astrophysics Data System (ADS)

    Jouet, Gwenael; Hutton, Eric W. H.; Syvitski, James P. M.; Berné, Serge

    2008-10-01

    Passive continental margin subsidence is initiated by the synrift mechanical stretching of the lithospheric upper brittle layer and continues during the postrift phase; the thermal cooling and contraction of the upwelled asthenosphere forces the margin to subside in addition to the overloads from sea water and sediments. Therefore, the total subsidence in stretched basins includes fault-controlled initial sinking, thermal subsidence and flexural isostatic compensations. Decoupling and estimating the different components of this subsidence from stratigraphic analysis and restricted geophysical and sedimentological databases remains problematic. In particular, backstripping the sediment layers requires a well-constrained geological framework. A method is proposed here to investigate the subsidence history of a margin based on forward stratigraphic modelling. Using the Sedflux model, several experiments are done using generally agreed upon assumptions on the parameters describing lithospheric rheology and isostatic behaviour of a margin. The stratigraphic modelling of the Rhône deltaic margin during the last climatic cycle (125 kyr) provides an assessment of these parameter estimates and their influence on geohistory (tectonic/thermal subsidence and sediment loading). The model results confirm the important impact of water loading on vertical deflection along the platform between glacial low sea-level and interglacial high sea-level. Based on Gulf of Lions (NW Mediterranean) observations, a conceptual method that uses the stratigraphic simulations is produced in order to evaluate the different components of the total subsidence of a margin, and, in particular, the relative impact of tectonic subsidence and sediment load.

  1. 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.

  2. Comparison of the triple-point temperatures of {sup 20}Ne, {sup 22}Ne and normal Ne

    SciTech Connect

    Nakano, T.; Tamura, O.; Nagao, K.

    2013-09-11

    At the National Metrology Institute of Japan (NMIJ), the triple points of {sup 20}Ne and {sup 22}Ne were realized using modular sealed cells, Ec3Ne20 and Ec8Ne22, made by the Istituto Nazionale di Ricerca Metrologica (INRiM) in Italy. The difference of the triple-point temperatures of {sup 20}Ne and {sup 22}Ne was estimated by using the sub-range of standard platinum resistance thermometers (SPRTs) calibrated by NMIJ on the International Temperature Scale of 1990 (ITS-90). The melting curves obtained with the Ec3Ne20 and Ec8Ne22 cells show narrow widths (0.1 mK) over a wide range of the inverse of the melted fraction (1/F) from 1/F=1 to 1/F=10. The liquidus point T{sub tp} estimated by the melting curves from F∼0.5 to F∼0.85 using the Ec8Ne22 is 0.146 29 (4) K higher than that using the Ec3Ne20 cell, which is in good agreement with that observed by INRiM using the same cells. After correction of the effect of impurities and other isotopes for Ec3Ne20 and Ec8Ne22 cells, the difference of T{sub tp} between pure {sup 20}Ne and pure {sup 22}Ne is estimated to be 0.146 61 (4) K, which is consistent with the recent results reported elsewhere. The sub-ranges of SPRTs computed by using the triple point of {sup 20}Ne or {sup 22}Ne realized by the Ec3Ne20 cell or the Ec8Ne22 cell in place of the triple point of Ne for the defining fixed point of the ITS-90 are in good agreement with those realized on the basis of the ITS-90 at NMIJ within 0.03 mK, which is much smaller than the non-uniqueness and the sub-range inconsistency of SPRTs.

  3. MicroBooNE Electronics

    NASA Astrophysics Data System (ADS)

    Kaleko, David

    2013-04-01

    MicroBooNE is a neutrino experiment under construction at Fermi National Lab. It employs a 10mx2.6mx(2.5m drift length) 86 ton liquid argon time projection chamber (TPC) active volume to record ionization signals from particles produced in neutrino interactions, and uses scintillation light detected by a PMT array to provide precise interaction timing information. The MicroBooNE readout electronics system includes both TPC and PMT readout electronics which digitize neutrino interaction signals at 2MHz and 64MHz, respectively. The TPC electronics readout system processes ionization signals from the three wire planes to two readout streams: one for triggered neutrino events, and a second one for continuous readout. The PMT readout system generates the trigger. This talk will describe the MicroBooNE readout system, its physics requirements, and specifications. Various tests which have been performed to exercise the data flow and integration with DAQ system, including data volume and integrity tests, will be described.

  4. Geochronometry and thermochronometry using nucleogenic 21Ne

    NASA Astrophysics Data System (ADS)

    Farley, K. A.; Flowers, R. M.; Vasconcelos, P. M.

    2011-12-01

    Nucleogenic 21Ne is produced by the interaction of α particles with 18O. While the cross section for this reaction is small (about 1 α in 25 million participates), 21Ne excesses can be measured in a variety of minerals, forming the basis of (U-Th)/Ne chronometry. Previous work focused on thermochronometry of U, Th rich trace minerals. For example, Gautheron et al. (2005) studied nucleogenic Ne in zircon and inferred a closure temperature of ~400 C. Our preliminary Ne diffusion data on Durango apatite suggests Tc ~280 C. The method can also be applied to phases with much lower U and Th contents in which the 21Ne is measurable on old and/or large specimens. We have obtained (U-Th)/Ne ages on ~50 mg samples of iron oxides with ppm-level U and Th and Ne ages of 50-500 Ma. For example, hematites from the Neoproterozoic (?) Urucum BIF yield a 21Ne age of 470 ± 15 Ma and post-depositional hydrothermal hematite in the Redwall Limestone in the Grand Canyon yields an age of 251 ± 11 Ma. In both cases (U-Th)/He ages are more than 100 Myr younger. Outstanding issues with this method are 1) the diffusivity of Ne - are we measuring cooling ages or formation ages?, 2) how well known is the production rate?, and 3) in what minerals is the air component sufficiently small to permit precision measurements of 21Ne excesses?

  5. Polyphase basin evolution of the Vienna Basin inferred from 3D visualization of sedimentation setting and quantitative subsidence

    NASA Astrophysics Data System (ADS)

    Lee, Eun Young; Novotny, Johannes; Wagreich, Michael

    2016-04-01

    This study analyzed and visualized data from 210 wells using a MATLAB-based program (BasinVis 1.0) for 3D visualization of sediment distribution, thickness, and quantitative subsidence of the northern and central Vienna Basin. The sedimentation settings for selected horizons were visualized to 3D sediment distribution maps, isopach maps, and cross-sections. Subsidence of the study area resulted in 3D subsidence depth and rate maps of basement and tectonic subsidences. Due to the special position of the Vienna Basin, the basin evolution was influenced by the regional tectonics of surrounding units. The 2D/3D maps provided insights into the polyphase evolution of the Vienna Basin, which is closely related to changes in the changing regional stress field and the paleoenvironmental setting. In the Early Miocene, the sedimentation and subsidence were shallow and E-W/NE-SW trending, indicating the development of piggy-back basins. During the late Early Miocene, maps show wider sedimentation and abruptly increasing subsidence by sinistral strike-slip faults, which initiated the Vienna pull-apart basin system. The sediments of the Early Miocene were supplied through a small deltaic system entering from the south. After thin sedimentation and shallow subsidence of the early Middle Miocene, the development of the Vienna Basin was controlled and accelerated mainly by NE-SW trending synsedimentary normal faults, especially the Steinberg fault. From the Middle Miocene, the subsidence was decreasing overall, however the tectonic subsidence show regionally different patterns. This study suggests that a major tensional regime change, from transtension to E-W extension, caused laterally varying subsidence across the Vienna Basin. The Late Miocene was characterized by the slowing down of basement and tectonic subsidence. From the middle Middle to Late Miocene, enormous amount of sediments supplied by a broad paleo-Danube delta complex on the western flank of the basin. The latest

  6. Defensive platform size and survivability. [Platform survivability

    SciTech Connect

    Canavan, Gregory H.

    1988-06-01

    This report discusses the survivability of space platforms, concentrating on space based kinetic energy interceptors. It evaluates the efficacy of hardening, maneuver, self-defense, and deception in extending the survivability of platforms of varying sizes to expected threats, concluding that they should be adequate in the near and mid terms.

  7. Segway robotic mobility platform

    NASA Astrophysics Data System (ADS)

    Nguyen, Hoa G.; Morrell, John; Mullens, Katherine D.; Burmeister, Aaron B.; Miles, Susan; Farrington, Nathan; Thomas, Kari M.; Gage, Douglas W.

    2004-12-01

    The Segway Robotic Mobility Platform (RMP) is a new mobile robotic platform based on the self-balancing Segway Human Transporter (HT). The Segway RMP is faster, cheaper, and more agile than existing comparable platforms. It is also rugged, has a small footprint, a zero turning radius, and yet can carry a greater payload. The new geometry of the platform presents researchers with an opportunity to examine novel topics, including people-height sensing and actuation modalities. This paper describes the history and development of the platform, its characteristics, and a summary of current research projects involving the platform at various institutions across the United States.

  8. Miocene uplift of the NE Greenland margin linked to plate tectonics: Seismic evidence from the Greenland Fracture Zone, NE Atlantic.

    NASA Astrophysics Data System (ADS)

    Døssing, Arne; Japsen, Peter; Watts, Anthony; Nielsen, Tove; Jokat, Wilfried; Thybo, Hans

    2016-04-01

    Tectonic models predict that, following breakup, rift margins undergo only decaying thermal subsidence during their post-rift evolution. However, post-breakup stratigraphy beneath the NE Atlantic shelves shows evidence of regional-scale unconformities, commonly cited as outer margin responses to inner margin episodic uplift, including the formation of coastal mountains. The origin of these events remains enigmatic. We present a seismic reflection study from the Greenland Fracture Zone - East Greenland Ridge (GFZ-EGR) and the NE Greenland shelf. We document a regional intra-Miocene seismic unconformity (IMU), which marks the termination of syn-rift deposition in the deep-sea basins and onset of: (i) thermo-mechanical coupling across the GFZ, (ii) basin compression, and (iii) contourite deposition, north of the EGR. The onset of coupling across the GFZ is constrained by results of 2-D flexural backstripping. We explain the thermo-mechanical coupling and the deposition of contourites by the formation of a continuous plate boundary along the Mohns and Knipovich ridges, leading to an accelerated widening of the Fram Strait. We demonstrate that the IMU event is linked to onset of uplift and massive shelf-progradation on the NE Greenland margin. Given an estimated middle-to-late Miocene (~15-10 Ma) age of the IMU, we speculate that the event is synchronous with uplift of the East and West Greenland margins. The correlation between margin uplift and plate-motion changes further indicates that the uplift was triggered by plate tectonic forces, induced perhaps by a change in the Iceland plume (a hot pulse) and/or by changes in intra-plate stresses related to global tectonics.

  9. Miocene uplift of the NE Greenland margin linked to plate tectonics: Seismic evidence from the Greenland Fracture Zone, NE Atlantic

    NASA Astrophysics Data System (ADS)

    Døssing, Arne; Japsen, Peter; Watts, Anthony B.; Nielsen, Tove; Jokat, Wilfried; Thybo, Hans; Dahl-Jensen, Trine

    2016-02-01

    Tectonic models predict that following breakup, rift margins undergo only decaying thermal subsidence during their postrift evolution. However, postbreakup stratigraphy beneath the NE Atlantic shelves shows evidence of regional-scale unconformities, commonly cited as outer margin responses to inner margin episodic uplift, including the formation of coastal mountains. The origin of these events remains enigmatic. We present a seismic reflection study from the Greenland Fracture Zone-East Greenland Ridge (GFZ-EGR) and the NE Greenland shelf. We document a regional intra-Miocene seismic unconformity (IMU), which marks the termination of synrift deposition in the deep-sea basins and onset of (i) thermomechanical coupling across the GFZ, (ii) basin compression, and (iii) contourite deposition, north of the EGR. The onset of coupling across the GFZ is constrained by results of 2-D flexural backstripping. We explain the thermomechanical coupling and the deposition of contourites by the formation of a continuous plate boundary along the Mohns and Knipovich ridges, leading to an accelerated widening of the Fram Strait. We demonstrate that the IMU event is linked to onset of uplift and massive shelf progradation on the NE Greenland margin. Given an estimated middle to late Miocene (~15-10 Ma) age of the IMU, we speculate that the event is synchronous with uplift of the east and west Greenland margins. The correlation between margin uplift and plate motion changes further indicates that the uplift was triggered by plate tectonic forces, induced perhaps by a change in the Iceland plume (a hot pulse) and/or by changes in intraplate stresses related to global tectonics.

  10. Oil migration pattern in the Sirte Basin

    SciTech Connect

    Roohi, M.; Aburawi, R.M.

    1995-08-01

    Sirte Basin is an asymmetrical cratonic basin, situated in the north-central part of Libya. It covers an area of over 350,000km{sup 2} and is one of the most prolific oil-producing basins in the world. Sirte Basin is divided into large NW-SE trending sub-parallel platforms and troughs bounded by deep seated syndepositional normal faults. A very unique combination of thick sediments with rich source rocks in the troughs vs. thinner sediments with prolific reservoir rocks on the platforms accounts for the productivity of the basin. Analysis of oil migration pattern in the Sirte Basin will certainly help to discover the remaining reserves, and this can only be achieved if the important parameter of structural configuration of the basin at the time of oil migration is known. The present paper is an attempt to analyse the time of oil migration, to define the structural picture of the 4 Basin during the time of migration and to delineate the most probable connecting routes between the hydrocarbon kitchens and the oil fields.

  11. Isotopic Fractionation of 20Ne, 21Ne, and 22Ne in a Simulated Thermal Gradient

    NASA Astrophysics Data System (ADS)

    Jester, B.; Dominguez, G.

    2014-12-01

    Computer simulations allow for the analysis of the thermodynamic properties of systems which are difficult or impossible to do experimentally. Isotopic fractionation in thermal gradients is an example of a system which is not fully understood but could provide background for understanding variations in fractionations like those observed for noble gases in terrestrial and extraterrestrial material. Using a recently developed molecular dynamics simulation focused on the accuracy of the simulated physics, the isotopic fractionation of Neon in a thermal gradient was analyzed in order to provide a correlation between the fractionation and the experimental system's properties. Various ratios of isotopes 20Ne, 21Ne, and 22Ne were simulated in a thermal gradient ranging from 218 K to 233 K for a variety of time scales. Data was collected for various configurations including box sizes on the order of 1 nm to 100 μm. The simulated thermal conductivity was determined and compared with known values. The analysis indicates that the dimensions of the box heavily influence the magnitude of the isotopic fractionation in the thermal gradient.

  12. 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.

  13. Nearshore half-grabens as analogues for offshore, early Carboniferous rift basins along the SW Barents Sea Margin

    NASA Astrophysics Data System (ADS)

    Koehl, Jean-Baptiste; Bergh, Steffen G.; Indrevær, Kjetil; Lea, Halldis; Bergø, Espen; Henningsen, Tormod; Forthun, Tore; Faleide, Jan-Inge

    2016-04-01

    The present study focuses on the onshore-offshore correlation of brittle faults along the SW Barents Sea Margin, northern Norway. Several studies indicate that the SW Barents Sea Margin experienced a pulse of extensional deformation in the Late Devonian?-early Carboniferous, shortly after the Caledonian contractional deformation ended. The formation of major brittle faults and associated offshore basins that represent targets for hydrocarbon exploration, such as the NE-SW trending Nordkapp Basin, are thought to have initiated during this rifting event. Half-graben structures similar in shape and orientation to the southern segment of the Nordkapp Basin have been identified on the Finnmark Platform and in nearshore areas in coastal Finnmark, northern Norway. Although relatively smaller, these half-graben structures display the same asymmetric, sigma-shaped to triangular architecture in map view as the Nordkapp Basin and also initiated in the earliest Carboniferous, as confirmed by fossiliferous assemblages from shallow cores. The triangular shape of these half-graben structures is related to the presence of possible fault segments of the Trollfjord-Komagelv Fault Zone that trend WNW-ESE and partly truncate the NE-SW trending, sometimes arcuate, extensional brittle faults that bound the half-graben structures. High-resolution bathymetry data show that these half-graben structures internally display minor, NE-SW trending brittle faults and relatively high seafloor relief, thus possible fault displacement, at the intersection between these minor faults and the major, arcuate bounding faults. Microstructural analysis of fault-rocks in nearby onshore fault zones showed multiple generations of cataclasite, suggesting several episodes of faulting in the region. A major goal for future work will be to constrain the exact timing of the faulting event(s) with K/Ar radiometric dating of onshore fault-rocks. This may help estimating the timing of potential fluid migration

  14. Crustal structure of the northeastern margin of the Tibetan plateau from the Songpan-Ganzi terrane to the Ordos basin

    USGS Publications Warehouse

    Liu, M.; Mooney, W.D.; Li, S.; Okaya, N.; Detweiler, S.

    2006-01-01

    The 1000-km-long Darlag-Lanzhou-Jingbian seismic refraction profile is located in the NE margin of the Tibetan plateau. This profile crosses the northern Songpan-Ganzi terrane, the Qinling-Qilian fold system, the Haiyuan arcuate tectonic region, and the stable Ordos basin. The P-wave and S-wave velocity structure and Poisson's ratios reveal many significant characteristics in the profile. The crustal thickness increases from northeast to southwest. The average crustal thickness observed increases from 42??km in the Ordos basin to 63??km in the Songpan-Ganzi terrane. The crust becomes obviously thicker south of the Haiyuan fault and beneath the West-Qinlin Shan. The crustal velocities have significant variations along the profile. The average P-wave velocities for the crystalline crust vary between 6.3 and 6.4??km/s. Beneath the Songpan-Ganzi terrane, West-Qinling Shan, and Haiyuan arcuate tectonic region P-wave velocities of 6.3??km/s are 0.15??km/s lower than the worldwide average of 6.45??km/s. North of the Kunlun fault, with exclusion of the Haiyuan arcuate tectonic region, the average P-wave velocity is 6.4??km/s and only 0.5??km/s lower than the worldwide average. A combination of the P-wave velocity and Poisson's ratio suggests that the crust is dominantly felsic in composition with an intermediate composition at the base. A mafic lower crust is absent in the NE margin of the Tibetan plateau from the Songpan-Ganzi terrane to the Ordos basin. There are low velocity zones in the West-Qinling Shan and the Haiyuan arcuate tectonic region. The low velocity zones have low S-wave velocities and high Poisson's ratios, so it is possible these zones are due to partial melting. The crust is divided into two layers, the upper and the lower crust, with crustal thickening mainly in the lower crust as the NE Tibetan plateau is approached. The results in the study show that the thickness of the lower crust increases from 22 to 38??km as the crustal thickness increases from

  15. Eustatic implications of late Miocene depositional sequences in the Melilla Basin, northeastern Morocco

    NASA Astrophysics Data System (ADS)

    Cunningham, Kevin J.; Benson, Richard H.; Rakic-El Bied, Kruna; McKenna, Larry W.

    1997-01-01

    The age (˜5.78 Ma or lower chron C3r) of the major drawdown of the Paleo-Mediterranean Sea during the Messinian Salinity Crisis has been established by combining results from stratigraphy, paleontology, magnetostratigraphy, and argon dating for a late Miocene sedimentary succession in the Melilla Basin, NE Morocco. This event is inferred from a marine-to-continental series of carbonate and siliciclastic rocks that record the end of Messinian marine deposition in the Melilla Basin and presumably marks the final isolation of the Paleo-Mediterranean Sea. The evidence from the Melilla Basin is approximately coeval with an increase in benthic foraminiferal δ18O values from a deep-marine section in the Bou Regreg valley, NW Morocco (Hodell et al., 1994). This increase suggests that a glacio-eustatic lowering of sea level, at least, contributed to the final closure of the Mediterranean during the Messinian Salinity Crisis. The marine-to-continental succession onlaps a carbonate complex that contains evidence for multiple relative sea-level changes leading up to the main drawdown. From bottom to top, the carbonate complex is composed of: (1) an onlapping ramp; (2) a prograding bioclastic platform; (3) a prograding and, locally, downstepping Porites-reef complex; and (4) a topography-draping sequence composed of grainstones, Porites reefs, and stromatolites (terminal carbonate complex of Esteban, 1979). The transgressive ramp correlates to relatively low values of benthic foraminiferal δ18O values from a Tortonian-to-lower Messinian section at Bou Regreg (Hodell et al., 1994). This correlation indicates, at least in part, a link between rising sea level and a reduction in global ice volume during deposition of the ramp. A major fall in relative sea level (˜60 m) occurred near the demise of the reef complex during chron C3n.1n at 5.95 ± 0.10 Ma. This signals the initiation of drawdown and changing environmental conditions in the Melilla Basin (a marginal basin), and

  16. Stabilized floating platforms

    DOEpatents

    Thomas, David G.

    1976-01-01

    The subject invention is directed to a floating platform for supporting nuclear reactors and the like at selected offshore sites. The platform is provided with a stabilizer mechanism which significantly reduces the effects of wave action upon the platform and which comprises a pair of relatively small floats attached by rigid booms to the platform at locations spaced therefrom for reducing wave pitch, acceleration, and the resonance period of the wave.

  17. Seismic and geologic characteristics of drowning events on carbonate platforms

    SciTech Connect

    Erlich, R.N.; Barrett, S.E. )

    1990-05-01

    Carbonate platform drowning events were recorded in Late Jurassic-Early Cretaceous carbonates of the Baltimore Canyon area, and early Miocene carbonates of the Pearl River Mouth basin. Cursory examination of seismic data from both areas would suggest that the platforms appear to fit the classic definition of a drowning unconformity. Lithologic and paleontologic data however, indicate that depositional hiatuses vary widely in each area (from 0-25 Ma in the Baltimore Canyon area, to no hiatus, but a condensed section in the Pearl River Mouth basin). The sedimentary sequence produced during a drowning event (the drowning sequence) in both areas is gradational with underlying shallow platform carbonates and, in some places, overlying deeper marine limestones and shales. Facies models illustrate that drowning event, in general, can appear as instantaneous or gradual changes in lithologic and seismic data. However, evidence from platforms adjacent to continental margins (Baltimore Canyon) and isolated open ocean atolls and banks (Pearl River Mouth basin) indicates that their response to drowning is different. In addition, bypass/erosional and accretionary carbonate platforms also respond somewhat differently to drowning events. The geologic characteristics of drowning events on carbonate platforms include gradational lower (and sometimes upper) contacts, chemical sedimentation, open-marine shelf sediments, and variable loss of time at the upper boundary. Late-growth shelf margin reefs can also be a diagnostic feature of drowned platforms. Seismic characteristics include horizontal to subhorizontal basinal marine onlap and basin-parallel reflector continuity above the carbonate sequence boundary. Proper recognition of the seismic and geologic characteristics of drowning events can lead to better reservoir-seal predictions, and to correct reconstruction of the depositional and tectonic/eustatic history of an area.

  18. Cretaceous carbonate platforms - emerging concepts and open problems

    SciTech Connect

    Schlager, W.

    1988-02-01

    The Cretaceous is a time of both spectacular growth and abrupt demise of carbonate platforms. Tectono-eustatic rise of sea level coupled with sediment-starvation in the ocean basins produced exceptionally high platforms. Because platform slopes steepen with height whereas siliciclastic slopes do not, the flanks of these high-rising platforms were onlapped by more gently dipping siliciclastics when the platforms ceased to grow. Future studies will have to separate these termination unconformities from the geometrically similar lowstand unconformities. Simultaneously, a carbonate sea level curve should be constructed solely from the record of the platform tops and compared with the onlap curves of seismic stratigraphy. The abrupt demise of Cretaceous platforms is even more remarkable than their rapid growth. In the Valanginian, the Aptian, the late Albian, the late Cenomanian, and the Turonian, platforms were drowned or reduced in size. The mid-Cretaceous events affected platforms in all major oceans and point to a global crisis of carbonate platforms, probably caused by environmental change such as oceanic anoxic events. A worldwide study is required to date these events and search for their causes in the record of life, climate, ocean circulation, and ocean chemistry. A third field of future research is the record of paleoclimate in the tidal flats and lagoons of the platforms on the northern and southern margins of Tethys. Climate modeling has identified this zone as a particularly sensitive switch in the ocean-atmosphere system of the Cretaceous.

  19. 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

  20. 78 FR 23280 - Agency Information Collection Activities: United States-Caribbean Basin Trade Partnership Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-18

    ...-Caribbean Basin Trade Partnership Act (CBTPA) AGENCY: U.S. Customs and Border Protection (CBP), Department... collection requirement concerning the United States-Caribbean Basin Trade Partnership Act (CBTPA). This... Rulings, Office of International Trade, 90 K Street NE., 10th Floor, Washington, DC 20229- 1177, at...

  1. Photoionization of the neon–rare gas dimers NeAr, NeKr, and NeXe

    SciTech Connect

    Pratt, Stephen T.; Dehmer, Patricia M.

    1982-01-01

    The relative photoionization cross sections for the heteronuclear neon--rare gas dimers NeAr, NeKr, and NeXe were measured at a wavelength resolution of 0.15 Â for NeAr and 0.28 Â for NeKr and NeXe in the energy region between the molecular ionization threshold and the atomic ²P⁰1/2 ionization limit of the heavier rare gas atom. The dimer ionization potentials are 15.685±0.004 eV for NeAr, 13.950±0.003 eV for NeKr, and 12.094±0.004 eV for NeXe. Combining these values with the known values of the atomic ionization potentials and the neutral ground state dissociation energies yields values of the A ²Σ⁺1/2 ionic ground state dissociation energies of 0.079±0.004 eV for NeAr, 0.055±0.003 eV for NeKr, and 0.041±0.004 eV for NeXe. Molecular Rydberg structure, which shows strong similarities to the atomic structure in the region of the autoionizing Beutler--Fano resonances, has been partially analyzed in terms of Rydberg series converging to the B ²Π1/2 state of the dimer ion. Vertical binding energies for the individual Rydberg states were determined based on the assumption that the Rydberg states dissociate to a neon atom in the ¹S0 ground state plus a rare gas atom in an ns'[1/2]⁰1 or nd'[3/2]⁰1 excited state. Values of the vertical binding energies of the B ²Π1/2 ionic state were determined from the series limits and are 0.022±0.002 eV for NeAr, 0.018±0.004 eV for NeKr, and 0.014±0.002 eV for NeXe.

  2. The role of strain partitioning on intermontane basin inception and isolation, External Western Gibraltar Arc

    NASA Astrophysics Data System (ADS)

    Jiménez-Bonilla, A.; Expósito, I.; Balanyá, J. C.; Díaz-Azpiroz, M.; Barcos, L.

    2015-12-01

    The intermontane Ronda Basin, currently located in the Western Betics External Zones, started as an embayment of the Betic foreland basin during the Tortonian. We have characterized a post-Serravallian, basin-related deformation event that overprinted the former fold-and-thrust belt. Updated structural and kinematic maps allow us to identify NW-SE basinward-dipping normal faults at the southwestern and northeastern boundaries of the basin and NE-SW shortening structures (large-scale folds and reverse faults) affecting both the outcropping basement and partially the basin infill. In order to test the possible tectonic activity of these structures during the last 5 Ma, exhaustive geomorphologic analyses in the Ronda Basin area have been done. This included the qualitative study of relief and drainage network, together with the characterization of quantitative indices (SLk, Smf, Vf and HI). These results obtained from this analysis are coherent with structural data and suggest that the identified post-Serravallian structures were active up to at least 5 Ma. We also conclude that the Ronda Basin was generated by along strike segmentation of the relief in the Western Betics induced by NE-SW (arc-parallel) stretching accompanied with NW-SE shortening. In the NW basin boundary, the strain was partitioned into ENE-WSW dextral strike-slip faults and NE-SW shortening structures, which gave rise to a Messinian transpressive structural high that disconnected the former Ronda Basin from its parental foreland basin.

  3. 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).

  4. Floor Plans Engine Removal Platform, Hold Down Arm Platform, ...

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

    Floor Plans - Engine Removal Platform, Hold Down Arm Platform, Hydraulic Equipment Platforms, Isometric Cutaway of Engine Removal Platform, Isometric Cutaway of Hold Down Arm Platform, Isometric Cutaway of Hydraulic Platforms and Engine Support System Access - Marshall Space Flight Center, Saturn V S-IC Static Test Facility, West Test Area, Huntsville, Madison County, AL

  5. 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.

  6. 40Ar/ 39Ar dating of the pre-evaporitic Messinian marine sequences of the Melilla basin (Morocco): a proposal for some biosedimentary events as isochrons around the Alboran Sea

    NASA Astrophysics Data System (ADS)

    Roger, S.; Münch, Ph.; Cornée, J. J.; Saint Martin, J. P.; Féraud, G.; Pestrea, S.; Conesa, G.; Ben Moussa, A.

    2000-06-01

    In the Mediterranean region, the Melilla basin (NE Morocco) represents a key area that recorded biosedimentary events and environmental changes relative to the pre-evaporitic Messinian times. 40Ar/ 39Ar dating of volcanic tuffs interbedded all along the Melilla Messinian shelf carbonates and coeval basin deposits has been performed in order to date accurately three main pre-evaporitic biosedimentary events: the prograding bioclastic deposition and the oligospecific prograding Porites coral reef buildings with coeval Halimeda blooms, both within the platform, and the diatomite deposition basinward. The new age data allow a precise chronological framework to be established for the pre-evaporitic sequence of Melilla basin demonstrating that diatomitic deposits are coeval with both prograding bioclastic and reefal units. The prograding bioclastic carbonate unit related to boreal influences in coeval basinal diatomites, began at least at 6.73±0.02 Ma and ended at 6.46±0.03 Ma. The oligospecific prograding Porites coral-reefs and Halimeda beds and coeval warm-water diatomites began at least at 6.46±0.03 Ma. Previous 40Ar/ 39Ar ages indicate that they ended prior to 6.0±0.1 Ma. Both biosedimentological similarities and chronological accordance within several platforms and adjacent basins all around the Alboran Sea show that these main bioevents, dated in Melilla, are synchronous over the Alboran realm. This accurate time scale for these pre-evaporitic biosedimentary events (6.9-6.0 Ma) is in accordance with the most recent work on the latter period corresponding to the Messinian Salinity Crisis.

  7. Onshore and offshore basins of northeast Libya: Their origin and hydrocarbon potential

    SciTech Connect

    Shegewi, O.M.

    1992-01-01

    A comprehensive data base of more than 3000 km of seismic lines, gravity and magnetic data, more than 30 subsurface well logs, and surface geology data were utilized to examine and interpret the sedimentary and tectonic history of the onshore and offshore parts of Northeast Libya and their hydrocarbon potential. The Dernah-Tobruk and Benghazi offshore basins form the northern parts of the study area. The Cyrenaica Stable Platform represents the southern parts. The Sirual Trough stretches E-W and opens into the Antelat Trough in the west. Between these elements is the uplifted areas of the Al Jabal Al Akhdar. Six principal tectonic phases were responsible for the formation and development of these structural elements: the pre-Mesozoic phase, the Triassic-Jurassic rifting phase, the Neocomian and the Aptian-Albian renewed rifting phases, the Late Cretaceous-Paleocene uplifting phase; and the Eocene-Middle Oligocene rifting phase. Oceanic crust of probable Aptian-Albian age is evident on the seismic lines north of the master fault marking the southern boundary of the rift separating the north African plate and Apulia. The western boundary of the Dernah High displayed clearly NE-SW strike-slip movement of these trajectories. Oceanic crust is also present west of the Dernah High. Positive gravity and magnetic anomalies traverse parallel to the boundary of this oceanic plate Mesogea. The prerequisites for commercial hydrocarbon production are present in abundance. Reservoirs ranging in age from Paleozoic clastics in the Cyrenaica Stable Platform to Mesozoic and Tertiary carbonates throughout the rest of the region. Several deep sites for the generation of hydrocarbons were also present, including the rifted northern parts of the Dernah-Tobruk basin, the Antelat Trough and the Cyrenaica Passive Margin. The Cretaceous and Tertiary section in the study area contain several potential seal rocks. Several potential trap types are also present.

  8. MiniBooNE Oscillation Results

    SciTech Connect

    Djurcic, Zelimir; /Columbia U.

    2009-07-01

    These proceedings summarize the MiniBooNE {nu}{sub {mu}} {yields} {nu}{sub e} results, describe the first {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e} result, and current analysis effort with the NuMI neutrinos detected in the miniBooNE detector.

  9. Multitarget, quantitative nanoplasmonic electrical field-enhanced resonating device (NE2RD) for diagnostics.

    PubMed

    Inci, Fatih; Filippini, Chiara; Baday, Murat; Ozen, Mehmet Ozgun; Calamak, Semih; Durmus, Naside Gozde; Wang, ShuQi; Hanhauser, Emily; Hobbs, Kristen S; Juillard, Franceline; Kuang, Ping Ping; Vetter, Michael L; Carocci, Margot; Yamamoto, Hidemi S; Takagi, Yuko; Yildiz, Umit Hakan; Akin, Demir; Wesemann, Duane R; Singhal, Amit; Yang, Priscilla L; Nibert, Max L; Fichorova, Raina N; Lau, Daryl T-Y; Henrich, Timothy J; Kaye, Kenneth M; Schachter, Steven C; Kuritzkes, Daniel R; Steinmetz, Lars M; Gambhir, Sanjiv S; Davis, Ronald W; Demirci, Utkan

    2015-08-11

    Recent advances in biosensing technologies present great potential for medical diagnostics, thus improving clinical decisions. However, creating a label-free general sensing platform capable of detecting multiple biotargets in various clinical specimens over a wide dynamic range, without lengthy sample-processing steps, remains a considerable challenge. In practice, these barriers prevent broad applications in clinics and at patients' homes. Here, we demonstrate the nanoplasmonic electrical field-enhanced resonating device (NE(2)RD), which addresses all these impediments on a single platform. The NE(2)RD employs an immunodetection assay to capture biotargets, and precisely measures spectral color changes by their wavelength and extinction intensity shifts in nanoparticles without prior sample labeling or preprocessing. We present through multiple examples, a label-free, quantitative, portable, multitarget platform by rapidly detecting various protein biomarkers, drugs, protein allergens, bacteria, eukaryotic cells, and distinct viruses. The linear dynamic range of NE(2)RD is five orders of magnitude broader than ELISA, with a sensitivity down to 400 fg/mL This range and sensitivity are achieved by self-assembling gold nanoparticles to generate hot spots on a 3D-oriented substrate for ultrasensitive measurements. We demonstrate that this precise platform handles multiple clinical samples such as whole blood, serum, and saliva without sample preprocessing under diverse conditions of temperature, pH, and ionic strength. The NE(2)RD's broad dynamic range, detection limit, and portability integrated with a disposable fluidic chip have broad applications, potentially enabling the transition toward precision medicine at the point-of-care or primary care settings and at patients' homes. PMID:26195743

  10. Multitarget, quantitative nanoplasmonic electrical field-enhanced resonating device (NE2RD) for diagnostics

    PubMed Central

    Inci, Fatih; Filippini, Chiara; Ozen, Mehmet Ozgun; Calamak, Semih; Durmus, Naside Gozde; Wang, ShuQi; Hanhauser, Emily; Hobbs, Kristen S.; Juillard, Franceline; Kuang, Ping Ping; Vetter, Michael L.; Carocci, Margot; Yamamoto, Hidemi S.; Takagi, Yuko; Yildiz, Umit Hakan; Akin, Demir; Wesemann, Duane R.; Singhal, Amit; Yang, Priscilla L.; Nibert, Max L.; Fichorova, Raina N.; Lau, Daryl T.-Y.; Henrich, Timothy J.; Kaye, Kenneth M.; Schachter, Steven C.; Kuritzkes, Daniel R.; Steinmetz, Lars M.; Gambhir, Sanjiv S.; Davis, Ronald W.; Demirci, Utkan

    2015-01-01

    Recent advances in biosensing technologies present great potential for medical diagnostics, thus improving clinical decisions. However, creating a label-free general sensing platform capable of detecting multiple biotargets in various clinical specimens over a wide dynamic range, without lengthy sample-processing steps, remains a considerable challenge. In practice, these barriers prevent broad applications in clinics and at patients’ homes. Here, we demonstrate the nanoplasmonic electrical field-enhanced resonating device (NE2RD), which addresses all these impediments on a single platform. The NE2RD employs an immunodetection assay to capture biotargets, and precisely measures spectral color changes by their wavelength and extinction intensity shifts in nanoparticles without prior sample labeling or preprocessing. We present through multiple examples, a label-free, quantitative, portable, multitarget platform by rapidly detecting various protein biomarkers, drugs, protein allergens, bacteria, eukaryotic cells, and distinct viruses. The linear dynamic range of NE2RD is five orders of magnitude broader than ELISA, with a sensitivity down to 400 fg/mL This range and sensitivity are achieved by self-assembling gold nanoparticles to generate hot spots on a 3D-oriented substrate for ultrasensitive measurements. We demonstrate that this precise platform handles multiple clinical samples such as whole blood, serum, and saliva without sample preprocessing under diverse conditions of temperature, pH, and ionic strength. The NE2RD’s broad dynamic range, detection limit, and portability integrated with a disposable fluidic chip have broad applications, potentially enabling the transition toward precision medicine at the point-of-care or primary care settings and at patients’ homes. PMID:26195743

  11. Production of Ne Auger electrons by Ne/+/ bombardment of Mg and Al surfaces

    NASA Technical Reports Server (NTRS)

    Ferrante, J.; Pepper, S. V.

    1976-01-01

    A description is given of experiments which provide evidence for the production of an inner shell vacancy in the Ne by the asymmetric Ne-Mg and Ne-Al collision. In addition, autoionization states of neutral Ne have been observed. These states are to be distinguished from the more usual case in Auger electron spectroscopy of de-excitation of an ion with a core vacancy. The experiments involved the bombardment of Mg and Al surfaces with Ne(+) ions. A LEED-Auger system equipped with an ion gun and a four-grid retarding potential analyzer operated in the usual dN(E)/dE mode was used.

  12. He and Ne isotopic ratios along the Terceira Rift: implications for the Azores mantle source

    NASA Astrophysics Data System (ADS)

    Madureira, P.; Moreira, M. A.; Nunes, J.; Lourenco, N.; Carvalho, M.; Mata, J.; Pinto de Abreu, M.

    2010-12-01

    Noble gas data (He and Ne) on olivine phenocrysts obtained from Azores’ lavas sampled along the Terceira Rift will be presented in this work. The Terceira Rift is considered as one of the slowest spreading system in the world (Vogt & Jung, 2004). Lava samples were collected inland at S. Miguel, Terceira, Graciosa, Pico and Faial Islands as well at sea at D. João de Castro Bank and south Hirondelle basin, the latter being sampled by the ROV cruises in 2008 and 2009. Noble gas data were analyzed in the Noblesse mass spectrometer housed at the IPGP. The most primitive He isotopic ratios were obtained from Pico, Terceira and Hirondelle olivines. Most Ne isotopic ratios are similar to the present-day atmosphere, but distinct 20Ne/22Ne ratios were found for the majority of submarine samples and also Pico and Faial Islands, defining mixing lines with the atmospheric end-member with slopes greater than that defined from MORB lavas. The He-Ne systematics shows that most of the new noble gas data fit in a mixing model between a dominant MORB-type mantle source and a relatively primitive mantle source related with the regional Azores component. However, data from the D. João de Castro Bank argue for the presence of a radiogenic He end-member distinct from MORB. References: Vogt, P. & Jung W. (2004). Earth Planet. Sci. Lett., 218: 77 90.

  13. Basin Dynamics and Sedimentary Infilling of Miocene Sandstone Reservoir Systems In Eastern Tunisian African Margin

    NASA Astrophysics Data System (ADS)

    Bédir, Mourad; Khomsi, Sami

    2015-04-01

    Most of hydrocarbon accumulations and aquifers within the Cap Bon, Gulf of Hammamet and Sahel basins in eastern tunisian foreland are reservoired within the Upper Miocene Birsa and Saouaf sandstones and shales Formations. In the gulf of Hammamet, these sandstones constitutes oil and gas fields and are exploited on anticline highs and described as varying from shoreface to shallow marine and typically exhibit excellent reservoir quality of 30% to 35% porosity and good permeability from 500 to 1100 md. In addition, the fracturing of faults enhanced the reservoir quality potential. In contrary, the same hydrocarbon reservoirs are important hydrogeologic ones in the Cap Bon and Sahel basins with huge amount of hundred millions of cubic meters of water only partially exploited. Integrated wire line logging correlations, seismic sequence stratigraphic, tectonics and outcrop geologic analogue studies had permitted to highlight the basin structuring and sedimentary environments of sequence deposits infilling of the reservoir distribution between high platforms to subsiding graben and syncline basins bounded by deep-seated transtensive and transpressive flower faults. Seven third order sequence deposits limited by downlap prograding and onlap/toplap aggrading/retrograding system tracts extend along the eastern margin around the three basins by facies and thickness variances. System tracts exhibit around high horst and graben a channelized and levee infillings extending from 100 meters to more than a kilometer of width. They present a stacked single story and multistory channels types showing space lateral and vertical migrations along NE-SW, E-W and N-S directions. Paleogeographic depositional reservoir fair maps distribution highlight deltaic horst domain with floodplain and incised valley of fluvial amalgamed and braided sandstones distributary channels that occupy the high folded horsts. Whereas folded horst-graben and syncline borders domain of Shelf prodelta are

  14. Omnidirectional holonomic platforms

    SciTech Connect

    Pin, F.G.; Killough, S.M.

    1994-06-01

    This paper presents the concepts for a new family of wheeled platforms which feature full omnidirectionality with simultaneous and independently controlled rotational and translational motion capabilities. The authors first present the orthogonal-wheels concept and the two major wheel assemblies on which these platforms are based. They then describe how a combination of these assemblies with appropriate control can be used to generate an omnidirectional capability for mobile robot platforms. The design and control of two prototype platforms are then presented and their respective characteristics with respect to rotational and translational motion control are discussed.

  15. Siberian Platform: Geology and Natural Bitumen Resources

    USGS Publications Warehouse

    Meyer, Richard F.; Freeman, P.A.

    2006-01-01

    Summary: The Siberian platform is located between the Yenisey River on the west and the Lena River on the south and east. The Siberian platform is vast in size and inhospitable in its climate. This report is concerned principally with the setting, formation, and potential volumes of natural bitumen. In this report the volumes of maltha and asphalt referred to in the Russian literature are combined to represent natural bitumen. The generation of hydrocarbons and formation of hydrocarbon accumulations are discussed. The sedimentary basins of the Platform are described in terms of the Klemme basin classification system and the conditions controlling formation of natural bitumen. Estimates of in-place bitumen resources are reviewed and evaluated. If the bitumen volume estimate is confined to parts of identified deposits where field observations have verified rock and bitumen grades values, the bitumen resource amounts to about 62 billion barrels of oil in-place. However, estimates of an order of magnitude larger can be obtained if additional speculative and unverified rock volumes and grade measures are included.

  16. Concrete production floating platforms

    SciTech Connect

    Letourneur, O.; Falcimaigne, J.

    1981-01-01

    The floating production platforms operating in the North Sea are adapted from drilling semisubmersibles which allow only a limited payload capacity. Experience of concrete production platforms constructed for the North Sea has led Sea Tank Co. to propose a floating platform which offers large payload and oil storage capacities similar to those of existing fixed platforms. Sea Tank Co. and Institut Francais du Petrole joined forces in early 1976 to study the feasibility of a concrete floating production platform incorporating the structure and the production riser together. The results of this 3-yr program show that the concrete floating structure is economically attractive for permanent utilization on a production site. Furthermore, concrete has definite advantages over other materials, in its long term behavior.

  17. The thermal environment of Cascadia Basin

    NASA Astrophysics Data System (ADS)

    Johnson, H. Paul; Hautala, Susan L.; Bjorklund, Tor A.

    2012-07-01

    Located adjacent to the NE Pacific convergent boundary, Cascadia Basin has a global impact well beyond its small geographic size. Composed of young oceanic crust formed at the Juan de Fuca Ridge, igneous rocks underlying the basin are partially insulated from cooling of their initial heat of formation by a thick layer of pelagic and turbidite sediments derived from the adjacent North American margin. The igneous seafloor is eventually consumed at the Cascadia subduction zone, where interactions between the approaching oceanic crust and the North American continental margin are partially controlled by the thermal environment. Within Cascadia Basin, basement topographic relief varies dramatically, and sediments have a wide range of thickness and physical properties. This variation produces regional differences in heat flow and basement temperatures for seafloor even of similar age. Previous studies proposed a north-south thermal gradient within Cascadia Basin, with high geothermal flux and crustal temperatures measured in the heavily sedimented northern portion near Vancouver Island and lower than average heat flux and basement temperatures predicted for the central and southern portions of the basin. If confirmed, this prediction has implications for processes associated with the Cascadia subduction zone, including the location of the "locked zone" of the megathrust fault. Although existing archival geophysical data in the central and southern basin are sparse, nonuniformly distributed, and derived from a wide range of historical sources, a substantial N-S geothermal gradient appears to be confirmed by our present compilation of combined water column and heat flow measurements.

  18. Coulomb Energies in ^18Ne

    NASA Astrophysics Data System (ADS)

    Sherr, R.; Fortune, H. T.

    1998-10-01

    Coulomb energies of the ^18Ne mirrors of the levels of ^18O vary considerably from state to state, an effect understood as arising from their different configurations. All the low-lying positive-parity states in these nuclei can be described in terms of two nucleons coupled to an ^16O core plus a collective component (most probably four-particle two-hole (4p-2h)). We have computed Coulomb energies using one such formulation(Lawson, Serduke and Fortune, Phys. Rev. C 14), 1245 (1976).. Two-particle energies arise from coupling a neutron to single-particle states of ^17O, and a proton to the mirror states of ^17F. For the 4p-2h component, we use the ^14O-^14C mass difference, plus a ph Coulomb term(Sherr and Bertsch, Phys. Rev. C 12), 1671 (1975).. Agreement is perhaps slightly better than another such attempt(Nero, Adelberger and Dietrich, Phys. Rev. C 24), 1864 (1981). using wave functions from Benson and Flowers.

  19. News from KM3NeT

    SciTech Connect

    Katz, Ulrich F.; Collaboration: KM3NeT Collaboration

    2014-11-18

    KM3NeT is a future research infrastructure in the Mediterranean Sea, hosting a multi-cubic-kilometre neutrino telescope and nodes for Earth and Sea sciences. In this report we shortly summarise the genesis of the KM3NeT project and present key elements of its technical design. The physics objectives of the KM3NeT neutrino telescope and some selected sensitivity estimates are discussed. Finally, some first results from prototype operations and the next steps towards implementation – in particular the first construction phase in 2014/15 – are described.

  20. Chicxulub impact basin: Gravity characteristics and implications for basin morphology and deep structure

    NASA Technical Reports Server (NTRS)

    Sharpton, Virgil L.; Burke, Kevin; Hall, Stuart A.; Lee, Scott; Marin, Luis E.; Suarez, Gerardo; Quezada-Muneton, Juan Manuel; Urrutia-Fucugauchi, Jaime

    1993-01-01

    The K-T-aged Chicxulub Impact Structure is buried beneath the Tertiary carbonate rocks of the Northern Yucatan Platform. Consequently its morphology and structure are poorly understood. Reprocessed Bouguer (onshore) and Free Air (offshore) gravity data over Northern Yucatan reveal that Chicxulub may be a 200-km-diameter multi-ring impact basin with at least three concentric basin rings. The positions of these rings follow the square root of 2 spacing rule derived empirically from analysis of multi-ring basins on other planets indicating that these rings probably correspond to now-buried topographic basin rings. A forward model of the gravity data along a radial transect from the southwest margin of the structure indicates that the Chicxulub gravity signature is compatible with this interpretation. We estimate the basin rim diameter to be 204 +/- 16 km and the central peak ring diameter (D) is 104 +/- 6 km.

  1. Photon beam quality correction factors for the NE2571A and NE2581A thimble ionization chambers using PENELOPE.

    PubMed

    Erazo, Fabián; Lallena, Antonio M

    2016-01-01

    The beam quality correction factor kQ,Q0 and the perturbation factor pQ for photon beams were calculated for the NE2571A and NE2581A ionization chambers, using the Monte Carlo simulation code PENELOPE. Results are compared to those quoted for the NE2571 and NE2581 chambers in previous works. Both kQ,Q0 and pQ obtained for NE2571A and NE2581A chambers agree with those of their predecessors NE2571 and NE2581 ones. PMID:26602965

  2. View from second floor platform looking up at subsequent platforms. ...

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

    View from second floor platform looking up at subsequent platforms. Note the Shuttle assembly outlined by the platform edges. - Marshall Space Flight Center, Saturn V Dynamic Test Facility, East Test Area, Huntsville, Madison County, AL

  3. Active NE-SW Compressional Strain Within the Arabian Plate

    NASA Astrophysics Data System (ADS)

    Floyd, M. A.; ArRajehi, A.; King, R. W.; McClusky, S.; Reilinger, R. E.; Douad, M.; Sholan, J.; Bou-Rabee, F.

    2012-12-01

    Motion of the Arabian plate with respect to Eurasia has been remarkably steady over more than 25 Myr as revealed by comparison of geodetic and plate tectonic reconstructions (e.g., McQuarrie et al., 2003, GRL; ArRajehi et al., 2010, Tectonics). While internal plate deformation is small in comparison to the rate of Arabia-Eurasia convergence, the improved resolution of GPS observations indicate ~ NE-SW compressional strain that appears to affect much of the plate south of latitude ~ 30°N. Seven ~ NE-SW oriented inter-station baselines all indicated shortening at rates in the range of 0.5-2 mm/yr, for the most part with 1-sigma velocity uncertainties < 0.4 mm/yr. Plate-scale strain rates exceed 2×10-9/yr. The spatial distribution of strain can not be resolved from the sparse available data, but strain appears to extend at least to Riyadh, KSA, ~ 600 km west of the Zagros Fold and Thrust Belt that forms the eastern, collisional boundary of the Arabian plate with Eurasia (Iran). Geodetic velocities in the plate tectonic reference frame for Arabia, derived from magnetic anomalies in the Red Sea (Chu and Gordon, 1998, GJI), show no significant E-W motion for GPS stations located along the Red Sea coast (i.e., geodetic and plate tectonic spreading rates across the Red Sea agree within their resolution), in contrast to sites in the plate interior and along the east side of the plate that indicate east-directed motions. In addition, NE-SW contraction is roughly normal to ~ N-S striking major structural folds in the sedimentary rocks within the Arabian Platform. These relationships suggest that geodetically observed contraction has characterized the plate for at least the past ~ 3 Myr. Broad-scale contraction of the Arabian plate seems intuitively reasonable given that the east and north sides of the plate are dominated by active continental collision (Zagros, E Turkey/Caucasus) while the west and south sides are bordered by mid-ocean ridge spreading (Red Sea and Gulf of

  4. The NeXus data format

    PubMed Central

    Könnecke, Mark; Akeroyd, Frederick A.; Bernstein, Herbert J.; Brewster, Aaron S.; Campbell, Stuart I.; Clausen, Björn; Cottrell, Stephen; Hoffmann, Jens Uwe; Jemian, Pete R.; Männicke, David; Osborn, Raymond; Peterson, Peter F.; Richter, Tobias; Suzuki, Jiro; Watts, Benjamin; Wintersberger, Eugen; Wuttke, Joachim

    2015-01-01

    NeXus is an effort by an international group of scientists to define a common data exchange and archival format for neutron, X-ray and muon experiments. NeXus is built on top of the scientific data format HDF5 and adds domain-specific rules for organizing data within HDF5 files, in addition to a dictionary of well defined domain-specific field names. The NeXus data format has two purposes. First, it defines a format that can serve as a container for all relevant data associated with a beamline. This is a very important use case. Second, it defines standards in the form of application definitions for the exchange of data between applications. NeXus provides structures for raw experimental data as well as for processed data. PMID:26089752

  5. UCB-NE-107 user's manual

    SciTech Connect

    Lee, W.W.L.

    1989-03-01

    The purpose of this manual is to provide users of UCB-NE-107 with the information necessary to use UCB-NE-107 effectively. UCB-NE-107 is a computer code for calculating the fractional rate of readily soluble radionuclides that are released from nuclear waste emplaced in water-saturated porous media. Waste placed in such environments will gradually dissolve. For many species such as actinides and rare earths, the process of dissolution is governed by the exterior flow field, and the chemical reaction rate or leaching rate. However, for readily soluble species such as /sup 135/Cs, /sup 137/Cs, and /sup 129/I, it has been observed that their dissolution rates are rapid. UCB-NE-107 is a code for calculating the release rate at the waste/rock interface, to check compliance with the US Nuclear Regulatory Commission's (USNRC) subsystem performance objective. It is an implementation of the analytic solution given below. 5 refs., 2 figs.

  6. The NeXus data format

    SciTech Connect

    Könnecke, Mark; Akeroyd, Frederick A.; Bernstein, Herbert J.; Brewster, Aaron S.; Campbell, Stuart I.; Clausen, Björn; Cottrell, Stephen; Hoffmann, Jens Uwe; Jemian, Pete R.; Männicke, David; Osborn, Raymond; Peterson, Peter F.; Richter, Tobias; Suzuki, Jiro; Watts, Benjamin; Wintersberger, Eugen; Wuttke, Joachim

    2015-01-30

    NeXus is an effort by an international group of scientists to define a common data exchange and archival format for neutron, X-ray and muon experiments. NeXus is built on top of the scientific data format HDF5 and adds domain-specific rules for organizing data within HDF5 files, in addition to a dictionary of well defined domain-specific field names. The NeXus data format has two purposes. First, it defines a format that can serve as a container for all relevant data associated with a beamline. This is a very important use case. Second, it defines standards in the form of application definitions for the exchange of data between applications. NeXus provides structures for raw experimental data as well as for processed data.

  7. The NeXus data format

    DOE PAGESBeta

    Könnecke, Mark; Akeroyd, Frederick A.; Bernstein, Herbert J.; Brewster, Aaron S.; Campbell, Stuart I.; Clausen, Björn; Cottrell, Stephen; Hoffmann, Jens Uwe; Jemian, Pete R.; Männicke, David; et al

    2015-01-30

    NeXus is an effort by an international group of scientists to define a common data exchange and archival format for neutron, X-ray and muon experiments. NeXus is built on top of the scientific data format HDF5 and adds domain-specific rules for organizing data within HDF5 files, in addition to a dictionary of well defined domain-specific field names. The NeXus data format has two purposes. First, it defines a format that can serve as a container for all relevant data associated with a beamline. This is a very important use case. Second, it defines standards in the form of application definitionsmore » for the exchange of data between applications. NeXus provides structures for raw experimental data as well as for processed data.« less

  8. Reassessment of offshore platforms

    SciTech Connect

    Nair, V.V.D.; Kuhn, J.M. )

    1993-05-01

    Data from Hurricane Andrew demonstrated that the systems and procedures in place for evacuating offshore workers and minimizing oil spills and environmental damage functioned as planned. While the vast majority of the platforms survived the storm with no damage, a few of the older platforms (installed prior to 1972) either collapsed or suffered severe damage. The collapsed platforms were designed with insufficient deck height to clear the storm waves. In recent years, the API RP 2A has introduced guidance for minimum air gap, minimum structures, platform inspection and platform reuse. These provisions, coupled with natural attribution of the older platforms, will significantly improve the performance of platforms in the future. The reliability of NDT techniques to detect major structural defects should be improved through continued research. While flooded member detection is used by several operators as a screening tool to detect major defects underwater, its reliability is not always good and further research is needed in this area. Another area of high priority research is related to the use of Remotely Operated Vehicles (ROV) to perform underwater inspection of structures. 51 refs., 7 figs.

  9. Petroleum potential of the Libyan sedimentary basins

    SciTech Connect

    Hammuda, O.S.; Sbeta, A.M.

    1988-08-01

    Contrary to prevailing opinion, all Libyan sedimentary basins and the Al-Jabal Al-Akhdar platform contain prolific petroleum accumulations with very high prospectivity. A systematic review of the types of traps and pays in this central part of the southern Mediterranean province reveals great variability in reservoir and source rock characteristics. The reservoir rocks are of almost all geologic ages. The thick source rock sequences also vary in nature and organic content. The organic-rich facies have accumulated in intracratonic and passive margin basins or in marginal seas. Most of the oil discovered thus far in these basins is found in large structural traps. Future discoveries of stratigraphic traps or small structural traps will require intensified efforts and detailed studies using up-to-date multidisciplinary techniques in sedimentary tectonics, biostratigraphic facies analysis, and geochemical prospecting in order to develop a better understanding of these basins, thus improving their prospectivity.

  10. MicroBooNE Detector Move

    SciTech Connect

    Flemming, Bonnie; Rameika, Gina

    2014-06-25

    On Monday, June 23, 2014 the MicroBooNE detector -- a 30-ton vessel that will be used to study ghostly particles called neutrinos -- was transported three miles across the Fermilab site and gently lowered into the laboratory's Liquid-Argon Test Facility. This video documents that move, some taken with time-lapse camerad, and shows the process of getting the MicroBooNE detector to its new home.

  11. MicroBooNE Detector Move

    ScienceCinema

    Flemming, Bonnie; Rameika, Gina

    2014-07-15

    On Monday, June 23, 2014 the MicroBooNE detector -- a 30-ton vessel that will be used to study ghostly particles called neutrinos -- was transported three miles across the Fermilab site and gently lowered into the laboratory's Liquid-Argon Test Facility. This video documents that move, some taken with time-lapse camerad, and shows the process of getting the MicroBooNE detector to its new home.

  12. Ladder attachment platform

    DOEpatents

    Swygert,; Richard, W [Springfield, SC

    2012-08-28

    A ladder attachment platform is provided that includes a base for attachment to a ladder that has first and second side rails and a plurality of rungs that extend between in a lateral direction. Also included is a user platform for having a user stand thereon that is carried by the base. The user platform may be positioned with respect to the ladder so that it is not located between a first plane that extends through the first side rail and is perpendicular to the lateral direction and a second plane that extends through the second side rail and is perpendicular to the lateral direction.

  13. Découverte de deux nouvelles espèces du genre Myocricetodon dans le Miocène supérieur du bassin d'Aït Kandoula (Maroc)Discovery of two new species of Myocricetodon genus in the Upper Miocene of Aït Kandoula basin (Morocco)

    NASA Astrophysics Data System (ADS)

    Benammi, Mouloud

    2001-08-01

    The Aı̈t Kandoula basin is known for its abundance of micromammal fauna. The systematic study of the fauna of two layers of the Afoud section (AF6 and AF5), highlights the presence of two new species: Myocricetodon afoudensis nov. sp. and Myocricetodon jaegeri nov. sp. These two layers are respectively dated at 10.1 and 6.3 Ma by magnetostratigraphic correlation.

  14. 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

  15. Tracing tetraether lipids from source to sink in the Rhône River system (NW Mediterranean)

    NASA Astrophysics Data System (ADS)

    Kim, Jung-Hyun; Ludwig, Wolfgang; Buscail, Roselyne; Dorhout, Denise; Sinninghe Damste, Jaap

    2015-06-01

    In this study, we investigated soils and river suspended particulate matter (SPM) collected in the Rhône and its tributary basins as well as marine surface sediments taken in the Rhône prodelta (Gulf of Lions, NW Mediterranean). Thereby, we traced the signal of branched glycerol dialkyl glycerol tetraethers (brGDGTs) from the source to sink via the Rhône River and its tributaries and identified sources of brGDGTs in rivers and marine sediments. Soil pH rather than the mean annual air temperature (MAAT) explains most of the observed variances of the brGDGT distribution in our soil dataset. The observed changes in the distribution of brGDGTs in the river SPM indicate that brGDGTs brought by the river to the sea are primarily derived from the lower Rhône and its tributary soils, even though in situ production in the river itself cannot be excluded. In marine surface sediments, it appears that the input of riverine brGDGTs is the primary source of brGDGTs in the Rhône prodelta, although the brGDGT composition may be further modified by the in situ production in the marine environment. More work is required to assess fully whether brGDGTs can be used to reconstruct the terrestrial paleoenvironmental changes using marine sediment cores taken in the Rhône prodelta close to the river mouth.

  16. Kilop Cretaceous Hardground (Kale, Gümüshane, NE Turkey):description and origin

    NASA Astrophysics Data System (ADS)

    Eren, Muhsin; Tasli, Kemal

    2002-06-01

    A hardground surface is well exposed in the Kilop area of Kale (Gümüshane, NE Turkey) which forms part of the Eastern Pontides. Here, the hardground is underlain by shallow water Lower Cretaceous limestones, and overlain by Upper Cretaceous red limestones/marls which contains a planktonic microfauna including Globotruncanidae. In the field, the recognition of the hardground is based on the presence of extensive burrows (especially vertical burrows), the encrusting rudistid bivalve Requienia, neptunian-dykes with infills of pelagic sediments and synsedimentary faults. Skolithos and Thalassinoides-type burrows are present. Some burrow walls show iron hydroxide-staining. The extensive burrowing occurred prior to lithification. On the other hand, the neptunian-dykes and synsedimentary faults, which cut the hard ground, occurred after the lithification. These features indicate the progressive hardening of the substrate. The burrowed limestone consists of an intrabioclastic peloidal grainstone which was deposited in an intertidal to shallow, subtidal, moderate to relatively high energy environment. The peloidal limestone shows little or no evidence of submarine cementation, characterized by only scarce relics of isopachous cement rims of bladed calcite spar. The grainstone cement is composed predominantly of blocky calcite and overgrowth calcite cements on the echinoid-fragments. The origin of this cement is controversial. Biostratigraphic analysis of the limestones demonstrates that there is a marked stratigraphic gap (hiatus), spanning the Aptian to the Santonian, in the Cretaceous of the Kilop area. The formation of the Kilop Hardground is related to the break-up and subsidence of the Eastern Pontides carbonate platform during the formation of the Black Sea backarc basin. Hardground development was initiated in a shallow marine environment of slow sedimentation and with moderate to high energy indicating slow subsidence. Later, the hardground subsided abruptly, as

  17. Neutrino-nucleus neutral current elastic interactions measurement in MiniBooNE

    SciTech Connect

    Perevalov, Denis

    2009-12-01

    The MiniBooNE experiment at the Fermi National Accelerator Laboratory (Fermilab) was designed to search for vμ → ve neutrino oscillations at Δm2 ~ 1 eV2 using an intense neutrino flux with an average energy Ev ~ 700 MeV. From 2002 to 2009 MiniBooNE has accumulated more than 1.0 x 1021 protons on target (POT) in both neutrino and antineutrino modes. MiniBooNE provides a perfect platform for detailed measurements of exclusive and semiinclusive neutrino cross-sections, for which MiniBooNE has the largest samples of events up to date, such as neutral current elastic (NCE), neutral current π0, charged current quasi-elastic (CCQE), charged current π+, and other channels. These measured cross-sections, in turn, allow to improve the knowledge of nucleon structure. This thesis is devoted to the study of NCE interactions. Neutrino-nucleus neutral current elastic scattering (vN → vN) accounts for about 18% of all neutrino interactions in MiniBooNE. Using a high-statistics, high purity sample of NCE interactions in MiniBooNE, the flux-averaged NCE differential cross-section has been measured and is being reported here. Further study of the NCE cross-section allowed for probing the structure of nuclei. The main interest in the NCE cross-section is that it may be sensitive to the strange quark contribution to the nucleon spin, Δs, this however requires a separation of NCE proton (vp → vp) from NCE neutron (vn → vn) events, which in general is a challenging task. MiniBooNE uses a Cherenkov detector, which imposes restrictions on the measured nucleon kinematic variables, mainly due to the impossibility to reconstruct the nucleon direction below the Cherenkov threshold. However, at kinetic energies above this threshold MiniBooNE is able to identify NCE proton events that do not experience final state interactions (FSI). These events were used for the Δs measurement. In this thesis

  18. ARM for Platform Application

    NASA Astrophysics Data System (ADS)

    Patte, Mathieu; Poupat, Jean-Luc; Le Meur, Patrick

    2015-09-01

    The activities described in this paper are part of the CNES R&T “Study of a Cortex-R ARM based architecture” performed by Airbus DS Space System & Electronics in 2014. With the support of CNES, Airbus DS has performed the porting of a representative space application software on an ARM based demonstration platform. This paper presents the platform itself, the activities performed at software level and the first results on this evaluation study.

  19. Repairing damaged platforms

    SciTech Connect

    Moore, R.E.; Kwok, P.H.; Wang, S.S.

    1995-10-01

    This paper introduces a unique method for strengthening of platforms and replacing damaged members. Extending the life of existing infrastructure is approved means of decreasing cash expenditures for new platforms and facilities. Platforms can be affected by corrosion, overloading and fatigue. The renovation and repair of existing offshore installations is an important part of offshore engineering. The basis behind this paper is an April, 1993 incident in the Arabian Gulf. A vessel broke loose from its moorings in a severe storm and collided with a wellhead platform. The collision severely damaged the platform buckling seven major support members and cracking joints throughout the structure. In view of the significant damage, there was an urgent need to repair the structure to avoid any further damage from potentially sever winter storm conditions. Various means of repair and their associated costs were evaluated: traditional dry hyperbaric welding, adjacent platforms, grouted clamped connections, and mechanical pipe connectors. The repair was completed using an innovative combination of clamps and wet welding to attach external braces to the structure.

  20. 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.

  1. Geological Setting and Petroleum Potential of the Paleozoic Hudson Platform, Northern Canada

    NASA Astrophysics Data System (ADS)

    Dietrich, J.; Hamblin, T.; Lavoie, D.; Duchesne, M.; Lajeunesse, P.; Zhang, Z.

    2009-05-01

    The Hudson Platform covers an area of 600,000 km2 and represents one of the largest Paleozoic sedimentary basins in Canada. The Hudson Platform contains the large Hudson Bay Basin and smaller Moose River Basin. The Hudson Bay and Moose River basins are surrounded and underlain by Precambrian igneous and metamorphic rocks of the Canadian Shield. The Hudson Platform contains Ordovician to Cretaceous sedimentary strata, with a maximum known thickness of about 2500 m in Hudson Bay. The lower Paleozoic succession includes Late Ordovician to Early Devonian shallow marine carbonates and thin mudstones, deposited during widespread early Paleozoic marine inundation of the Canadian Shield, and Early to Late Devonian marine carbonates, evaporates, and mudstones deposited in saucer-shaped, isolated basin depocentres. There is no record of late Paleozoic sedimentation in the region, perhaps related to cratonic uplift accompanying the Alleghenian Orogeny. Lower Paleozoic strata are unconformably overlain by thin, erosional remnants of Middle Jurassic and Early Cretaceous nonmarine sandstones, mudstones and lignite seams (Moose River Basin) and Early Cretaceous marine sandstones and mudstones (Hudson Bay Basin). The Hudson Platform is currently considered a frontier prospect for hydrocarbon exploration. However, the long- held view that the region is underlain by a thin sedimentary succession with no appreciable hydrocarbon source rocks or reservoir intervals is erroneous. Geological and geophysical data indicate the Hudson Bay Basin contains many prospective petroleum reservoir and trap types, potentially including hydrothermal dolomite. Recent studies indicate Upper Ordovician oil shales are widespread and may have generated hydrocarbons in deeper parts of the Hudson Bay Basin. New high resolution bathymetric surveys in northern Hudson Bay have led to the recognition of circular sea-floor depressions similar to fluid or gas-escape pockmarks. A modern re-evaluation of the

  2. Cross section analyses in MiniBooNE and SciBooNE experiments

    SciTech Connect

    Katori, Teppei

    2015-05-15

    The MiniBooNE experiment (2002-2012) and the SciBooNE experiment (2007-2008) are modern high statistics neutrino experiments, and they developed many new ideas in neutrino cross section analyses. In this note, I discuss selected topics of these analyses.

  3. Thermal regime and amplitude of lithosphere extension in the Sirte basin, Libya: Numerical estimates in the plane basin modeling system

    NASA Astrophysics Data System (ADS)

    Galushkin, Yu. I.; El Maghbi, Ali; El Gtlawi, M.

    2014-01-01

    The GALO basin modeling system has been applied for the numerical reconstruction of the subsidence history, variations in temperature, and maturity of the organic matter of sedimentary rocks composing the main tectonic structures of Sirte Basin. The reconstruction was carried out for eight sedimentary cross sections along the profile stretching from the Cyrenaica Platform on the eastern coast of the basin to the Hun Graben on its western wall. The interval of depths for temperature calculations included the sedimentary layer, consolidated crust, and the mantle to below 100 km. This extensive depth coverage made it possible to use the analysis of the variations in the tectonic subsidence of the basin for estimating the amplitudes and duration of the events of thermal activation and extension of the lithosphere of the basin in the history of its evolution. The modeling suggests that thermal activations of the lithosphere in the Albian-Cenomanian and Oligocene-Pleistocene are common for all tectonic structures of the Sirte Basin and the Cyrenaica Platform and that a relatively high temperature regime is also characteristic of the present-day conditions in the Sirte Basin and Cyrenaica Platform. To a considerable extent, such a regime is caused by the thermal activation of the lithosphere of the basin during the last 10 Ma. The intensity of this activation is highest in the western part of the basin, where it is accompanied by the highest erosion amplitudes. The analysis of the variations in tectonic subsidence of the basement also suggests a series of intervals of lithospheric extension, which accounts for the stages of relatively rapid subsidence of the basin. Two intervals of significant extension of the lithosphere in the Upper Cretaceous and Paleocene are common for all areas within the basin. Here, the total amplitudes of the crustal extension attained 1.5 in the central part of the Sirte Basin (the Ajdabiya and Maradah troughs and Zelten and Dahra platforms

  4. Geologic evolution of Uinta-Piceance basin province, northwestern Colorado and northeastern Utah

    SciTech Connect

    Johnson, S.Y.; Tuttle, M.L.; Bryant, B.H.; Dubiel, R.F.; Fouch, T.D.; Franczyk, K.J.; Grauch, V.J.S.; Grout, M.A.; Johnson, R.C.; Molenaar, C.M.; Nichols, D.J.; Nichols, K.M.; Nuccio, V.F.; Peterson, F.; Pitman, J.K.; Perry, W.J. Jr.; Potter, C.J.; Sawatzky, D.L.; Scott, R.W. Jr.; Verbeek, E.R.; Wanty, R.B. )

    1990-05-01

    The Uinta-Piceance basin province (UPBP) has a complex Phanerozoic history characterized by five distinct phases of basin development (1) The UPBP formed part of a continental platform shelf on the northwestern flank of North America during the early and middle Paleozoic. Cambrian through Mississippian strata consist mainly of carbonate rocks, shale, and quartzite; contain major unconformities; and thicken westward. (2) Pennsylvanian-Permian uplifts of the ancestral Rocky Mountain orogeny segmented this continental platform shelf into the Eagle, Paradox, and Oquirrh basins. Basin-margin tectonics and cyclic eustatic-climatic fluctuations strongly controlled deposition of the clastic, carbonate, and evaporitic fill of these basins. (3) During the early Mesozoic, the UPBP formed part of a slowly subsiding continental platform. Triassic-Jurassic rocks include eolian, alluvial, and lacustrine deposits that thicken and grade westward into marine facies. (4) Paleozoic and early Mesozoic strata in the westernmost part of the UPBP were thrust eastward during the late Mesozoic Sevier orogeny, causing subsidence in the adjacent foreland basin. The history of the UPBP part of this foreland basin is recorded by thick nonmarine deposits within and adjacent to the thrust belt that grade eastward into thinner accumulations of marine rocks. (5) The geometry and style of regional compressional deformation changed markedly with onset of the latest Cretaceous-Paleogene Laramide orogeny. Laramide uplifts segmented the UPBP foreland basin into the Uinta and Piceance intermontane lacustrine basins. The geometry of these lacustrine basins is notably different from that of the late Paleozoic segment basins.

  5. Far-Ultraviolet Emission Cross Sections of Ne 2 and Ne 3 Excited by Electron Impact

    NASA Technical Reports Server (NTRS)

    James, Geoffrey K.; Kanik, Isik; Ajello, Joseph M.

    1995-01-01

    We have measured the electron-impact-induced fluorescence spectrum of neon in the wavelength range 120-270 nm at a spectral resolution of 0.43 nm (FWHM). The strongest lines observed in the far-ultraviolet (FUV) spectrum of neon are assigned to terms of the doublet system of Ne 2 (2s(sup 2) 2p(sup 4)nl and the triplet system of Ne 3 (2s(sup 2)2p(sup 3)3l). Our FUV spectral data, obtained at 300 eV electron-impact energy, provide absolute emission cross sections of these Ne 2 and Ne 3 lines, and are compared to previous measurements where available. In addition, the excitation function of the strongest Ne II line observed at 191.6 nm was measured from threshold to 1000 eV electron-impact energy.

  6. Chapter 43: Assessment of NE Greenland: Prototype for development of Circum-ArcticResource Appraisal methodology

    USGS Publications Warehouse

    Gautier, D.L.; Stemmerik, L.; Christiansen, F.G.; Sorensen, K.; Bidstrup, T.; Bojesen-Koefoed, J. A.; Bird, K.J.; Charpentier, R.R.; Houseknecht, D.W.; Klett, T.R.; Schenk, C.J.; Tennyson, M.E.

    2011-01-01

    Geological features of NE Greenland suggest large petroleum potential, as well as high uncertainty and risk. The area was the prototype for development of methodology used in the US Geological Survey (USGS) Circum-Arctic Resource Appraisal (CARA), and was the first area evaluated. In collaboration with the Geological Survey of Denmark and Greenland (GEUS), eight "assessment units" (AU) were defined, six of which were probabilistically assessed. The most prospective areas are offshore in the Danmarkshavn Basin. This study supersedes a previous USGS assessment, from which it differs in several important respects: oil estimates are reduced and natural gas estimates are increased to reflect revised understanding of offshore geology. Despite the reduced estimates, the CARA indicates that NE Greenland may be an important future petroleum province. ?? 2011 The Geological Society of London.

  7. Interatomic Coulombic decay following Ne 1s Auger decay in NeAr

    SciTech Connect

    Ouchi, T.; Sakai, K.; Fukuzawa, H.; Ueda, K.; Higuchi, I.; Tamenori, Y.; Demekhin, Ph. V.; Chiang, Y.-C.; Stoychev, S. D.; Kuleff, A. I.; Mazza, T.; Schoeffler, M.; Nagaya, K.; Yao, M.; Saito, N.

    2011-05-15

    Using momentum-resolved electron-ion multicoincidence spectroscopy, we have investigated interatomic Coulombic decay (ICD) in the heteronuclear NeAr dimer following Ne 1s Auger decay. The measured intensity ratio for the three ICD transitions Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 1}P)Ar to Ne{sup 2+}(2p{sup -2} {sup 1}S)-Ar{sup +}(3p{sup -1}), Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 1}P)Ar to Ne{sup 2+}(2p{sup -2} {sup 1}D)-Ar{sup +}(3p{sup -1}), and Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 3}P)Ar to Ne{sup 2+}(2p{sup -2} {sup 3}P)-Ar{sup +}(3p{sup -1}) reasonably agree with predictions. The kinetic energy release distribution for the fragmentation to Ne{sup 2+}(2p{sup -2} {sup 1}D)-Ar{sup +}(3p{sup -1}) after the ICD transition from singlet Ne{sup 2+}(2s{sup -1}2p{sup -1} {sup 1}P)Ar state, which is a mirror image of the kinetic energy distribution of the emitted ICD electrons, suggests that the corresponding ICD rate is roughly two times lower than predicted by ab initio calculations.

  8. Transactional Network Platform: Applications

    SciTech Connect

    Katipamula, Srinivas; Lutes, Robert G.; Ngo, Hung; Underhill, Ronald M.

    2013-10-31

    In FY13, Pacific Northwest National Laboratory (PNNL) with funding from the Department of Energy’s (DOE’s) Building Technologies Office (BTO) designed, prototyped and tested a transactional network platform to support energy, operational and financial transactions between any networked entities (equipment, organizations, buildings, grid, etc.). Initially, in FY13, the concept demonstrated transactions between packaged rooftop air conditioners and heat pump units (RTUs) and the electric grid using applications or "agents" that reside on the platform, on the equipment, on a local building controller or in the Cloud. The transactional network project is a multi-lab effort with Oakridge National Laboratory (ORNL) and Lawrence Berkeley National Laboratory (LBNL) also contributing to the effort. PNNL coordinated the project and also was responsible for the development of the transactional network (TN) platform and three different applications associated with RTUs. This document describes two applications or "agents" in details, and also summarizes the platform. The TN platform details are described in another companion document.

  9. Carbonate platform development in northeast Australia

    SciTech Connect

    Davies, P.J.; Symonds, P.A.; Feary, D.A.; Pigram, C.J.

    1987-05-01

    In northeast Australia, the Great Barrier Reef and the Queensland and Marion plateaus comprise carbonate platforms separated by major rift basins. Cenozoic platform evolution has been dependent upon (1) northward drift of Australia from temperate into tropical latitudes; (2) subsidence pulses in the Eocene/Oligocene and the Pliocene/Pleistocene; (3) sea level oscillations; (4) continental and oceanic influences; and (5) paleophysiography and paleo-ocean chemistry. The evolution of each platform reflects the interaction of these factors on its development. Further, the evolution of the Queensland Plateau has markedly affected that of the Great Barrier Reef through its influence on circulation patterns. In the Eocene/Oligocene, and shelf on which the Great Barrier Reef grew protected the Marion Plateau from terrigenous influences, while in the late Miocene to early Pliocene the Marion Plateau formed the springboard from which the central and southern Great Barrier Reef developed. Models of platform development must take account of 1)early Eocene reef initiation on the Queensland Plateau concomitant with marine transgression into the adjacent rift troughs; 2)Eocene/Oligocene subsidence resulting in stepback of the reefs from the flank of the Queensland Plateau and reestablishment at higher bathymetric levels, concomitant clastic sedimentation along the tropical northern continental margin and temperate(.) carbonate progradation along the margin of the Marion Plateau; 3)extensive growth of Miocene reef complexes on the Queensland Plateau and the initiation of reef complexes on the Marion Plateau and on the northern section of the Great Barrier Reef; and 4)Pliocene subsidence leading to contraction of the area of reef growth on the Queensland Plateau, with almost total drowning of the Marion Plateau and stepback of the Miocene barrier and platform reefs to their present position on the central Great Barrier Reef.

  10. Universal visualization platform

    NASA Astrophysics Data System (ADS)

    Gee, Alexander G.; Li, Hongli; Yu, Min; Smrtic, Mary Beth; Cvek, Urska; Goodell, Howie; Gupta, Vivek; Lawrence, Christine; Zhou, Jainping; Chiang, Chih-Hung; Grinstein, Georges G.

    2005-03-01

    Although there are a number of visualization systems to choose from when analyzing data, only a few of these allow for the integration of other visualization and analysis techniques. There are even fewer visualization toolkits and frameworks from which one can develop ones own visualization applications. Even within the research community, scientists either use what they can from the available tools or start from scratch to define a program in which they are able to develop new or modified visualization techniques and analysis algorithms. Presented here is a new general-purpose platform for constructing numerous visualization and analysis applications. The focus of this system is the design and experimentation of new techniques, and where the sharing of and integration with other tools becomes second nature. Moreover, this platform supports multiple large data sets, and the recording and visualizing of user sessions. Here we introduce the Universal Visualization Platform (UVP) as a modern data visualization and analysis system.

  11. Geostationary multipurpose platforms

    NASA Technical Reports Server (NTRS)

    Bekey, I.; Bowman, R. M.

    1981-01-01

    In addition to the advantages generally associated with orbital platforms, such as improved reliability, economies of scale, simple connectivity of elements, reduced tracking demands and the restraint of orbital object population growth, geostationary platforms yield: (1) continuous access by fixed ground antennas for communications services; (2) continuous monitoring of phenomena over chosen regions of the earth's surface; (3) a preferred location for many solar-terrestrial physics experiments. The geostationary platform also offers a low-risk and economical solution to the impending saturation of the orbital arc/frequency spectrum, maximizing the capacity of individual slots and increasing the utility of the entire arc. It also allows the use of many small, simple and inexpensive earth stations through complexity inversion and high power per beam. Block diagram and operational flowcharts are provided.

  12. Evaluation of Ordos Basin in China

    SciTech Connect

    Zhou, J.G.

    1996-06-01

    Ordos basin lies in the north-central China, in a compression tectonic regime, with an area of approximately 250,000 km{sup 2}, including several pay zones ranging from Cambrian to Jurassic. It is one of the earliest-formed marine to continental-superimposed basin in China, characterized by Proterozoic basin-marginal rifling and Lower-Paleozoic carbonate platform development followed by western thrusting and foreland depression during Mesozoic. It underwent several tectonic movements and is covered by several structural layers, with many play types developed, primarily thrust and anticlinal plays in the west, and differential compaction (river-channel sand lens) or drape as well as buried hill plays in the basin center and east. Ordos basin is a prolific gas basin with an estimated resource potential of gas 656,091 billion m{sup 3} in the Paleozoic strata and oil 2.0474 billion tons in the Mesozoic strata. In 1986, in the western part of the basin, the well Tian-1 on the Tianchi structure tested gas at a rate of 16 x 10{sup 4} m{sup 3}/d (about 5.6496 MCF per day). By year-end 1991, only 26 wells had been drilled in the Jingbian to Hengshan areas (northeastern part of the basin), but 16 of them flowed commercial gas, ranging from 3.2 x 10{sup 4} m{sup 3}/d to 126 x 10{sup 4} m{sup 3}/d. However, the gas pipe just starts budding. Therefore, there will be a lot of gas yet to find, and the most critical factor for petroleum potential of each local structure or play in this basin is the reservoir development.

  13. The Personal Motion Platform

    NASA Technical Reports Server (NTRS)

    Park, Brian Vandellyn

    1993-01-01

    The Neutral Body Posture experienced in microgravity creates a biomechanical equilibrium by enabling the internal forces within the body to find their own balance. A patented reclining chair based on this posture provides a minimal stress environment for interfacing with computer systems for extended periods. When the chair is mounted on a 3 or 6 axis motion platform, a generic motion simulator for simulated digital environments is created. The Personal Motion Platform provides motional feedback to the occupant in synchronization with their movements inside the digital world which enhances the simulation experience. Existing HMD based simulation systems can be integrated to the turnkey system. Future developments are discussed.

  14. Electric Propulsion Orbital Platform

    NASA Technical Reports Server (NTRS)

    Friedly, V. J.; Ruyten, Wilhelmus M.; Litchford, R. J.; Garrison, G. W.

    1993-01-01

    This paper describes the Electric Propulsion Orbital Platform (EPOP), of which the primary objective is to provide an instrumented platform for testing electric propulsion devices in space. It is anticipated that the first flight, EPOP-1, will take place on the Shuttle-deployed Wake Shield Facility in 1996, and will be designed around a commercial 1.8 kW arcjet system which will be operated on gaseous hydrogen propellant. Specific subsystems are described, including the arcjet system, the propellant and power systems, and the diagnostics systems.

  15. Meso-/Cenozoic thermal and inversion history of the Tarfaya Basin and provenance analysis of the basin fill (Morocco)

    NASA Astrophysics Data System (ADS)

    Sehrt, Manuel; Glasmacher, Ulrich A.

    2014-05-01

    The Tarfaya Basin is the northern part of the Tarfaya-Laâyoune-Dakhla Basin that extends over 1000 km along the western Saharan margin from the Mauritanian border to the Canary Islands in the north. The basin is bounded by the Mauritanide thrust belt and Precambrian Reguibat Arch in the SE-E and the Palaeozoic fold belt of the Anti-Atlas in the NE. A large amount of Mesozoic terrigenous sedimentary rocks are deposited in most of the basins along the continental margin of Morocco indicating a major episode of erosion occurred during the rift and early post-rift period in the Central Atlantic. In the Tarfaya-Laâyoune-Dakhla Basin, the Mesozoic to Cenozoic sedimentary cover reaches a thickness of up to 12 km. The presence of high surface elevations in the Anti-Atlas mountain belt (2700 m) indicates a potential source area for the surrounding basins, i.e. the Tarfaya Basin. The present study was focused on the thermal and inversion history of the Tarfaya Basin, the provenance of the Meso-Cenozoic sedimentary rocks of the basin and additionally on the thermal and exhumation history of the Western Anti-Atlas. In order to characterize the t-T history, apatite and zircon fission-track dating, apatite and zircon (U-Th-Sm)/He dating and furthermore 2-D modelling with 'HeFTy' software has been carried out at Precambrian rocks of the Western Anti-Atlas and Cretaceous to Neogene sedimentary rocks from the Tarfaya Basin. Thermochronological data and t-T path modelling indicate an inversion of the onshore Tarfaya Basin in the Palaeogene. The provenance analysis suggests an almost continuous sediment transport from the Anti-Atlas to the Tarfaya Basin and a simultaneous sediment input from the Reguibat Shield.

  16. 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.

  17. Thermodynamics and equilibrium structure of Ne38 cluster: quantum mechanics versus classical.

    PubMed

    Predescu, Cristian; Frantsuzov, Pavel A; Mandelshtam, Vladimir A

    2005-04-15

    The equilibrium properties of classical Lennard-Jones (LJ38) versus quantum Ne38 Lennard-Jones clusters are investigated. The quantum simulations use both the path-integral Monte Carlo (PIMC) and the recently developed variational-Gaussian wave packet Monte Carlo (VGW-MC) methods. The PIMC and the classical MC simulations are implemented in the parallel tempering framework. The classical heat capacity Cv(T) curve agrees well with that of Neirotti et al. [J. Chem. Phys. 112, 10340 (2000)], although a much larger confining sphere is used in the present work. The classical Cv(T) shows a peak at about 6 K, interpreted as a solid-liquid transition, and a shoulder at approximately 4 K, attributed to a solid-solid transition involving structures from the global octahedral (Oh) minimum and the main icosahedral (C5v) minimum. The VGW method is used to locate and characterize the low energy states of Ne38, which are then further refined by PIMC calculations. Unlike the classical case, the ground state of Ne38 is a liquidlike structure. Among the several liquidlike states with energies below the two symmetric states (Oh and C5v), the lowest two exhibit strong delocalization over basins associated with at least two classical local minima. Because the symmetric structures do not play an essential role in the thermodynamics of Ne38, the quantum heat capacity is a featureless curve indicative of the absence of any structural transformations. Good agreement between the two methods, VGW and PIMC, is obtained. The present results are also consistent with the predictions by Calvo et al. [J. Chem. Phys. 114, 7312 (2001)] based on the quantum superposition method within the harmonic approximation. However, because of its approximate nature, the latter method leads to an incorrect assignment of the Ne38 ground state as well as to a significant underestimation of the heat capacity. PMID:15945633

  18. Basement blocks and basin inversion structures mapped using reprocessed Gulfrex 2D seismic data, Caribbean-South American oblique collisional zone

    NASA Astrophysics Data System (ADS)

    Escalona, A.; Sena, A.; Mann, P.

    2003-12-01

    We have reprocessed and reinterpreted more than 10,000 km of "Gulfrex" multi-channel 2D seismic reflection lines collected by Gulf Oil Corporation in 1972 along the northern margin of South America (offshore Venezuela and Trinidad). These digital data were donated to the University of Texas Institute for Geophysics and represent the largest single, digital reflection survey of the region. Reprocessing of these data included: format correction, filtering, post-stack multiple suppression, and fk migration. Reprocessed data were loaded and interpreted on a workstation. The data straddle a 2,000,000 km2 zone of Paleocene-Recent, time-transgressive, oblique collision between the Caribbean arc system and the passive continental margin of northern South America. Free-air, satellite gravity data shows the remarkable 1000-km-scale continuity of four basement ridges between the uncollided part of the Caribbean arc system (NS-trending Lesser Antilles arc) and the EW-trending collisional area north of Venezuela. The basement ridges involved in the Venezuelan collisional zone include: 1) Aruba-Bonaire-Curacao ridge that can be traced as a continuous feature to the Aves ridge remnant arc of the Lesser Antilles; 2) the partially inverted Blanquilla-Bonaire basin that can be traced into the Grenada back-arc basin; 3) Margarita-Los Testigos platform that can be traced to the Lesser Antilles volcanic arc; and 4) foreland basins and fold-thrust belts of eastern Venezuela (Serrania del Interior and Maturin basin) that can be traced to the Tobago forearc basin and Barbados accretionary prism. Gulfrex data document the progressive change of basinal fault systems from NS-striking normal faults formed in extensional, Lesser Antilles intra-arc settings to rotated and inverted, NE and EW-striking normal faults deformed in the collisional area north of Venezuela. Age of initial shortening of basinal areas and inversion of normal faults setting does not follow the simple, expected pattern of

  19. Transportation and platforms perspective

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1992-01-01

    The topics covered are presented in viewgraph form and include the following: Office of Aeronautics and Space Technology; space research and technology (R&T); space R&T mission statement; Space R&T program development; R&T strategy; Office of Space Science and Applications (OSSA) technology needs; transportation technology; and space platforms technology.

  20. Education Platforms for America

    ERIC Educational Resources Information Center

    District Administration, 2012

    2012-01-01

    What is at stake for K12 education in next month's presidential election? Both President Barack Obama (Democratic Party) and Gov. Mitt Romney (Republican Party) say improving education will be a top priority in their administrations, but their policies and initiatives would likely be quite different. While political platforms rarely offer detailed…

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

    NASA Technical Reports Server (NTRS)

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

    1985-01-01

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

  2. Multiphase Fault Evolution in a Rotational Margin Setting: Offshore Sirte Basin, Libya

    NASA Astrophysics Data System (ADS)

    Maddock, Paul; McCaffrey, Ken; Imber, Jonathon

    2013-04-01

    The aims of this study are to present a new structural interpretation of a well-calibrated regional 2D seismic dataset to constrain the timing and style of faulting in the Sirte embayment, offshore Libya, a Mesozoic-Cenozoic extension of the Sirte basin onshore north Africa. Due to rotation of the African continent since the Mesozoic, present-day fault orientations are not the same as during fault formation at various times since the early Palaeozoic. The approach has therefore been to integrate a structural model with published plate tectonic reconstructions in order to progressively restore fault orientations throughout the evolution of the Sirte embayment. Multiple phases of rifting can be observed in the offshore area, with major faulting episodes during the Aptian-Albian, Upper Cretaceous, mid-Eocene and Oligocene. Paleozoic basement structures have a dominant role in controlling the locations of later faults. The model shows how pre-existing structures have been reactivated during the main Cretaceous basin-forming episode, with some deeply-rooted basement faults remaining active into the mid-late Cretaceous. The orientation of basement faults with respect to the inferred regional stress direction appears to be a key influence on the type of faulting observed. In many parts of the Sirte Embayment, active faulting during the later Mesozoic is concentrated in fault zones directly above, or in the immediate hanging wall of older, deeper faults. The dominant stress field since the Cretaceous is consistent with the onshore Sirte trend with extension generally to the NE-SW giving NW-SE striking faults and fault zones. The orientation of pre-Mesozoic faults can be shown to have rotated anti-clockwise by 40° between formation and Cretaceous deformation, with a further 17° to the present day giving a total rotation of 57°. While the present day onshore trend of NW-SE horst and graben blocks has the greatest influence on the structure of the Sirte embayment

  3. A physical view of La Guajira Upwelling System, Colombian Basin, Caribbean Sea

    NASA Astrophysics Data System (ADS)

    Bernal, G.; Beier, E.; Barton, E. D.; Ruiz-Ochoa, M.; Correa, J. G.

    2013-05-01

    La Guajira Peninsula lies within a large upwelling system along the South Caribbean Coast, created by the NE trade winds. In this location, sea surface temperature (SST) exhibits the lowest mean value and the highest variability in the whole Colombian Basin. The seasonal variation of SST explains up to 75 % of the total variability. La Guajira coastal zone also experiences the highest values of wind stress and wind stress curl, with the greatest annual and semiannual variability in the Colombian Basin. It has been shown that wind stress curl enhances the upwelling over the region. Near 90% of the variability of SST in La Guajira can be explained by the seasonality plus the first three EOFs interannual modes: the first, synchronous throughout the Basin, is dominant, and consists of a uniform interannual variation in phase with the North Tropical Atlantic Index; the second co-varies strongly with the second mode of wind stress curl; and the third reflects the role of the vertical atmospheric circulation cell associated with the Caribbean Low Level Jet off Central America. The inclusion of wind stress curl with its maximum offshore of La Guajira explains in part the extension of cool coastal water into the Colombian Basin, with advection in filaments, eddies and meanders. In order to complement the physical knowledge of La Guajira upwelling system, an analysis of water masses, sea surface height, Ekman suction, Ekman transport and coastal upwelling index (CUI) was performed. Hydrographic data was obtained from gridded climatologies from the National Oceanographic Data Center (WOD01); sea surface height anomalies from the Archiving, Validation, and Interpretation of Satellite Oceanography (AVISO) data; and wind data from the Cross-Calibrated Multi-Platform Ocean Surface Wind Velocity Product for Meteorological and Oceanographic Applications (CCMP). The upwelling forms a local water mass, La Guajira surface water (LGSW), with the mixing of subtropical underwater and

  4. Contrasting evolutionary patterns of Lower Permian shelf and basinal facies, Midland basin, Texas

    SciTech Connect

    Mazzullo, S.J.; Reid, A.M.

    1987-05-01

    The evolution of carbonate and siliciclastic shelf-to-basin depositional systems of the Lower Permian in the Midland basin was influenced by eustatic fluctuations, changing shelf-margin biota, and concurrent tectonism. The development of these systems from Wolfcampian to Leonardian time (28-m.y. duration) involved seven distinct phases that are recognized seismically as third and lesser order cycles. These phases are (1) highstand progradational shelf carbonate packages, separated by low-stand deltaic and basinal shales, deposited during relatively long-term eustatic cycles (early Wolfcampian); the component carbonate systems evolved from ramps to distally steepened ramps associated with nonframe-building algal reefs and grainstones, with little resedimented foreshelf detritus; (2) dominantly carbonate deposition during the middle and early late Wolfcampian, with construction of offlapping (but laterally juxtaposed) progradational shelves with steep platform margins deposited during a lengthy period of stillstand and/or slow submergence; dolomitized platform-margin facies are composed of marine-cemented, sponge-algal reefs and grainstones, with resedimented carbonate megabreccia to micrite channels and lobes in the contiguous shale basin; (3) shelf emergence and erosion during a major late middle(.) to late Wolfcampian lowstand contemporaneous with basinwide tectonism, with mass wastage into the basin of the terminal Wolfcampian platform-margin carbonate section; (4) regional transgression and black shale deposition followed by a repeat of Phase 2 type systems in the latest Wolfcampian to earliest Leonardian but under arid conditions; rapid vertical platform margin accretion by dolomitized, marine-cemented, sponge-algal-coral reefs and grainstones, and deposition of thick foreshelf megabreccia wedges, aprons, channels, and lobes;

  5. 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

  6. 78 FR 73581 - Nebraska Disaster #NE-00055

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-06

    ... ADMINISTRATION Nebraska Disaster NE-00055 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY.../26/2014. ADDRESSES: Submit completed loan applications to: U.S. Small Business Administration... CONTACT: A. Escobar, Office of Disaster Assistance, U.S. Small Business Administration, 409 3rd Street...

  7. MiniBooNE oscillation searches

    SciTech Connect

    Brice, Stephen J.

    2008-01-01

    The range of oscillation analyses being pursued by the MiniBooNE collaboration is described. Focus is given to the various searches for electron neutrino appearance, but the disappearance of muon neutrinos and the appearance search for electron anti-neutrinos are covered as well.

  8. EC Detector at SciBooNE

    NASA Astrophysics Data System (ADS)

    Mariani, Camillo

    2009-04-01

    SciBooNE is an experiment to measure neutrino and anti-neutrino cross-sections on the Booster Neutrino Beam at Fermilab. The EC is an extruded lead sheets and scintillating fibers "spaghetti calorimeter" to provide longitudinal containment and energy measurement for electrons and photons.

  9. Data ingestion into NeQuick 2

    NASA Astrophysics Data System (ADS)

    Nava, B.; Radicella, S. M.; Azpilicueta, F.

    2011-12-01

    NeQuick 2 is the latest version of the NeQuick ionosphere electron density model developed at the Aeronomy and Radiopropagation Laboratory of the Abdus Salam International Centre for Theoretical Physics (ICTP) - Trieste, Italy with the collaboration of the Institute for Geophysics, Astrophysics and Meteorology of the University of Graz, Austria. It is a quick-run model particularly designed for trans-ionospheric propagation applications that has been conceived to reproduce the median behavior of the ionosphere. To provide 3-D specification of the ionosphere electron density for current conditions, different ionosphere electron density retrieval techniques based on the NeQuick adaptation to GPS-derived Total Electron Content (TEC) data and ionosonde measured peak parameters values have been developed. In the present paper the technique based on the ingestion of global vertical TEC map into NeQuick 2 will be validated and an assessment of the capability of the model to reproduce the ionosphere day-to-day variability will also be performed. For this purpose hourly GPS-derived global vertical TEC maps and hourly foF2 values from about 20 ionosondes corresponding to one month in high solar activity and one month in low solar activity period will be used. Furthermore, the first results concerning the ingestion of space-based GPS-derived TEC data will be presented.

  10. The (20)Ne interaction in extended matter

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Townsend, L. W.; Wong, M.; Schimmerling, W.

    1984-01-01

    Although heavy ion transport theory is developed to a relatively advanced stage, the present limitation in biomedical and electronic applications is the uncertainty in nuclear fragmentation parameters. The present status on Ne-20 beams is discussed and useful formulae are presented for future use in analysis of beam transport experiments.

  11. 76 FR 53018 - Nebraska Disaster #NE-00044

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-24

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Nebraska Disaster NE-00044 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY... State of Nebraska (FEMA- 4014-DR), dated 08/12/2011. Incident: Severe Storms, Tornadoes,...

  12. 75 FR 67162 - Nebraska Disaster #NE-00040

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-01

    ... From the Federal Register Online via the Government Publishing Office SMALL BUSINESS ADMINISTRATION Nebraska Disaster NE-00040 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY... Straight-line Winds. Incident Period: 09/13/2010 through 09/14/2010. DATES: Effective Date:...

  13. Eclipse Parallel Tools Platform

    SciTech Connect

    Watson, Gregory; DeBardeleben, Nathan; Rasmussen, Craig

    2005-02-18

    Designing and developing parallel programs is an inherently complex task. Developers must choose from the many parallel architectures and programming paradigms that are available, and face a plethora of tools that are required to execute, debug, and analyze parallel programs i these environments. Few, if any, of these tools provide any degree of integration, or indeed any commonality in their user interfaces at all. This further complicates the parallel developer's task, hampering software engineering practices, and ultimately reducing productivity. One consequence of this complexity is that best practice in parallel application development has not advanced to the same degree as more traditional programming methodologies. The result is that there is currently no open-source, industry-strength platform that provides a highly integrated environment specifically designed for parallel application development. Eclipse is a universal tool-hosting platform that is designed to providing a robust, full-featured, commercial-quality, industry platform for the development of highly integrated tools. It provides a wide range of core services for tool integration that allow tool producers to concentrate on their tool technology rather than on platform specific issues. The Eclipse Integrated Development Environment is an open-source project that is supported by over 70 organizations, including IBM, Intel and HP. The Eclipse Parallel Tools Platform (PTP) plug-in extends the Eclipse framwork by providing support for a rich set of parallel programming languages and paradigms, and a core infrastructure for the integration of a wide variety of parallel tools. The first version of the PTP is a prototype that only provides minimal functionality for parallel tool integration of a wide variety of parallel tools. The first version of the PTP is a prototype that only provides minimal functionality for parallel tool integration, support for a small number of parallel architectures, and basis

  14. Continental margin evolution of the northern Arabian platform in Syria

    SciTech Connect

    Best, J.A.; Barazangi, M. ); Al-Saad, D.; Sawaf, T.; Gebran, A. )

    1993-02-01

    Synthesis of available geological and geophysical data in the Syrian Arab Republic permits a descriptive account of the pre-Cenozoic geologic history of the northern Arabian platform. The northern Arabian platform appears to be a composite plate similar up to that interpreted in the rocks of the Arabian shield. The structural and stratigraphic relationships of the Paleozoic and Mesozoic sedimentary sections in Syria record the transformation of an eastward-facing Gondwana passive margin in the early Paleozoic into a westward-facing Levantine margin in the Mesozoic, at which time the northern platform was closely associated with the creation of the eastern Mediterranean basin. Timing of the margin transformation is inferred from the orientation and thickness variations of Lower Triassic rocks, but the transformation may have initiated as early as the Permian. The diversity and timing of geological features in Syria suggest that the northern Arabian platform did not behave as a rigid plate throughout its geological history. The present-day Palmyride mountain belt, located within the northern Arabian platform in Syria and initiated in the early Mesozoic as a northeast-trending rift nearly perpendicular to the Levantine margin, subsequently was inverted in the Cenozoic by transpression. The location of the rift may be associated with the reactivation of a zone of crustal weakness, i.e., a Proterozoic suture zone previously proposed from modeling of Bouguer gravity data. Thus, the northern and southern parts of the Arabian platform are similar in their respective geologic histories during the Proterozoic and Paleozoic; however, the northern Arabian platform was greatly affected by Mesozoic rifting and the creation of the eastern Mediterranean basin during the Mesozoic. 13 figs.

  15. Mesozoic magmatism and tectonics in NE Asia: Constrain on closing of the Mongol-Okhotsk Ocean

    NASA Astrophysics Data System (ADS)

    Wang, T.; Guo, L.; Zhang, L.; Zheng, Y.; Li, S.; Tong, Y.

    2013-12-01

    from some MCCs and Ar-Ar ages for mylonites suggest that the mid-lower-crustal extension probably initiated at ca. 150-145 Ma with a peak occurring 145-130 Ma, and continued to 130-120 Ma (Wang et al., 2011; 2012). Large extensional basins also occurred during this time. All these magmatism, extensional tectonics and basins consistently indicate large-scale extension in the NE Asia continent. Some Mesozoic igneous rocks in the NE margin of the NE Asian continent might also related to the Paleo-Pacific plate subduction. However, many of them, particularly far away from the Paleo-Pacific plate subduction zone, were likely related to the closing of the Mongol-Okhotsk Ocean. The transition from calc-alkaline I-type to high calc-alkaline or alkaline I- or A-type granitoids, and from crustal contraction (thrusts) to extension (MCCs, extensional basins) delineate the transition from continental collision following the scissors-like closing of the Ocean to post-collisional extension. All these suggest that the scissors-like closing of the Ocean took place during Middle and Late Jurassic.

  16. Floating platform with monolithically formed float members and platform

    SciTech Connect

    Finsterwalder, U.

    1981-06-30

    Floating platforms for various offshore facilities are formed of float members monolithically connected to a superposed platform. The float members are spherically shaped and are formed of reinforced or prestressed concrete. The platform can be a hollow planar member or it can be curved in one or two directions, and the platforms are formed of prestressed concrete. Cylindrical shafts can be used to connect the spherically shaped floats and the platform. Individual floating platforms can be connected by expansion joints and used as a runway. The float members can be constructed at the shoreline, launched into the water and held in a regular pattern while decked over with the platform. After completion of the construction procedure, the floating platform can be moved to an offshore location for use.

  17. Electron impact excitation of the Ne II and Ne III fine structure levels

    NASA Astrophysics Data System (ADS)

    Wang, Q.; Loch, S. D.; Pindzola, M. S.; Cumbee, R.; Stancil, P. C.; Ballance, C. P.; McLaughlin, B. M.

    2016-05-01

    Electron impact excitation cross sections and rate coefficients of the low lying levels of the Ne II and Ne III ions are of great interest in cool molecular environments including young stellar objects, photodissociation regions, active galactic nuclei, and X-ray dominated regions. We have carried out details computations for cross sections and rate coefficients using the Dirac R-matrix codes (DARC), the Breit-Pauli R-matrix codes (BP) and the Intermediate Coupling Frame Transformation (ICFT) codes, for both Ne II and Ne III. We also compare our results with previous calculations. We are primarily interested in rate coefficients in the temperature range below 1000 K, and the focus is on obtaining the most accurate rate coefficients for those temperatures. We present both a recommended set of effective collision strengths and an indication of the uncertainties on these values. Work at Auburn University and UGA partly supported by NASA Grant NNX15AE47G.

  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. Cenozoic uplift and erosion of structural landforms in NE Brazil

    NASA Astrophysics Data System (ADS)

    Gurgel, Silvana P. P.; Bezerra, Francisco H. R.; Corrêa, Antonio C. B.; Marques, Fernando O.; Maia, Rubson P.

    2013-03-01

    We investigate the evolution of uplifted areas in NE Brazil, which have been considered as residual landforms. The study focuses on the 130 km-long, 41 km-wide Pereiro Massif (PM). The structural control and the age of this uplift are the problems addressed in this study. We carried out topographic analysis, geomorphological and geological mapping, detailed structural analysis, and optically stimulated luminescence (OSL) dating to address these problems. The PM is bounded and cut by a system of steeply dipping normal and strike-slip faults, which control the morphology of the massif and associated sedimentary basins. The maximum uplift rate of the PM is 34 m.My- 1, as constrained by the age of flat topography capped by Miocene laterite, which represents the previous peneplain subsequently uplifted by ca. 600 m. The minimum uplift rate is 13 m.My- 1, as constrained by fission-track dating of differential crustal block movements across a nearby fault. In the Quaternary, erosion occurred mainly by fault-controlled scarp retreat under semi-arid conditions, with the formation of colluvial deposits along fault scarps and alluvial deposits in the low plains. These deposits are now dated between 46 and 0.4 ka, with a peak in sediment deposition in the Pleistocene/Holocene transition. It is concluded that the PM is a system of horsts and grabens that have been active in the Cenozoic.

  20. Mobility platform coupling device and method for coupling mobility platforms

    DOEpatents

    Shirey, David L.; Hayward, David R.; Buttz, James H.

    2002-01-01

    A coupling device for connecting a first mobility platform to a second mobility platform in tandem. An example mobility platform is a robot. The coupling device has a loose link mode for normal steering conditions and a locking position, tight link mode for navigation across difficult terrain and across obstacles, for traversing chasms, and for navigating with a reduced footprint in tight steering conditions.

  1. Seismic and geologic characteristics of drowning events on carbonate platforms

    SciTech Connect

    Erlich, R.N.; Barrett, S.F. ); Guo Bai Ju )

    1990-10-01

    Carbonate platform drowning events are recorded in Upper Jurassic-Lower Cretaceous carbonates of the Baltimore Canyon area, offshore US East Coast, and lower Miocene carbonates of the Pearl River Mouth Basin, offshore People's Republic of China. Cursory examination of seismic data from both areas would indicate that the platforms fit the classic definition of a drowning unconformity. However, detailed lithologic and paleontologic data indicate that the depositional/erosional hiatuses vary widely in each area, from 0-25 m.y. in the Baltimore Canyon area, to a condensed section with no hiatus in the Pearl River Mouth Basin. The sedimentary sequence produced during drowning in both areas is gradational with underlying shallow platform carbonates and, in some places, overlying deeper marine limestones and shales. The generalized facies models proposed for drowning events suggest that they may appear as instantaneous or gradual changes in geologic and seismic data. Because of this resolution problem, a distinction should be made between seismically and geologically defined unconformity surfaces. The geologic characteristics of drowning events on carbonate platforms include a gradational lower (and sometimes upper) contact, chemical sedimentation (glauconite, phosphate), open-marine shelf sediments, and a variable hiatus at the upper boundary. Data from isolated open-ocean atolls (Pearl River Mouth Basin) indicate that they respond differently to drowning, showing an asymmetric decrease in shallow platform environments as drowning occurs. Proper recognition by a geoscientist of the seismic and geological characteristics of drowning events can lead to better reservoir and seal estimates, and the correct reconstruction of the depositional, tectonic, and eustatic histories of an area.

  2. Calculation of electron wave functions and refractive index of Ne

    NASA Astrophysics Data System (ADS)

    Zhu, Min; Liu, Wei; Zhang, Tao

    2008-10-01

    The radial wave functions of inner electron shell and outer electron shell of a Ne atom were obtained by the approximate analytical method and tested by calculating the ground state energy of the Ne atom. The equivalent volume of electron cloud and the refractive index of Ne were calculated. The calculated refractive index agrees well with the experimental result. Relationship between the refractive index and the wave function of Ne was discovered.

  3. Sedimentation in Canada Basin, Western Arctic

    NASA Astrophysics Data System (ADS)

    Mosher, D. C.; Shimeld, J.; Jackson, R.; Hutchinson, D. R.; Chapman, B.; Chian, D.; Childs, J. R.; Mayer, L. A.; Edwards, B. D.; Verhoef, J.

    2010-12-01

    The Canada Basin of the western Arctic Ocean is the least studied ocean basin on Earth. Marine seismic field programs were conducted during the past 5 years in order to study the geology, sedimentary history and geomorphology of the region. As part of this program, five annual icebreaker expeditions acquired bathymetric, seismic reflection and seismic refraction data on a regional scale. More than 12,000 km of multi-channel seismic reflection data and 120 sonobuoy seismic refraction records over abyssal plain and continental rise regions of Canada Basin, Northwind Ridge and Alpha Ridge were acquired. The success of these programs was achieved through novel technical modifications to equipment to permit towing in heavy ice conditions and through collaboration between multiple Canadian and US agencies and institutions, enabling utilization of two ice breakers during seismic and multibeam data acquisition in heavy ice. The seafloor of the Canada Basin is remarkably flat-lying in its central region, with little bathymetric change over most of its extent. The sedimentary succession is generally flat lying with reflections extending over hundreds of km. These reflections onlap bathymetric highs, such as Alpha and Northwind ridges. The sedimentary succession is thickest in the Beaufort Sea region, reaching more than 6.5 km, and generally thins to the north and west. Reflection characteristics suggest that sediment volume input to the Arctic Ocean has been high and dominated by turbidity current deposition, similar to Amundsen and Nansen Basins of the eastern Arctic. These turbidites originate from the eastern and southern continental margins. There is no evidence of contemporaneous or post-depositional reworking by bottom currents. Additionally, there is little evidence of tectonic deformation after primary basin-forming events except in the NE quadrant, nearer Alpha Ridge. In this area, there is significant normal faulting propagating from basement through much of the

  4. Neotectonic evolution of the algerian seismogenic basins

    NASA Astrophysics Data System (ADS)

    Djellit, Hamou

    2013-04-01

    Neotectonic evolution of the algerian seismogenic basins H. Djellit and A.K. Yelles-Chaouche Tertiary evolution of the seismogenic algerian basins is characterized by three main neogene and quaternary episods which led to their structuration and the actual seismicity. Indeed, after the early paroxysmal alpines phases which built the structural edifice of the tellian chain, the three tectonic phases between the Cretaceous and the Oligo-Miocene period are: (1) a collapse of the north-kabylian zones and installation of the neogene basins from the Oligo-Miocene period (2) then a shortenning accommodate by conjugate NE-SW sinistral and NW-SE dextral strike slip faults, indicating a NNW-SSE stress orientation, (3) finally, a late shortening phase from the late quaternary to the actual period marked by thrusting faults with a south to south-east vegency. In the Mitidja basin (Algiers region) , the tectonic structurations in the neogene and plio-quaternary deposits correspond to: 1) a synchroneous collapse of the Oligo-Miocene deposits of the Kabylian deposits marked by the activity of synsedimentary norms faults with a general orientation from N040-050 to NW50 followed by (2) a folding oriented N060 which uplift the pliocene serie, this is visible along the Algiers-Sahel anticline. The strike slip faults which are less visible in the plio-quaternary deposits of the basin are more marked in the magmatic intrusions which cross-cut the neogene deposits Key-words: seismotectonic, basins, Neogene, Mitidja

  5. Common tester platform concept.

    SciTech Connect

    Hurst, Michael James

    2008-05-01

    This report summarizes the results of a case study on the doctrine of a common tester platform, a concept of a standardized platform that can be applicable across the broad spectrum of testing requirements throughout the various stages of a weapons program, as well as across the various weapons programs. The common tester concept strives to define an affordable, next-generation design that will meet testing requirements with the flexibility to grow and expand; supporting the initial development stages of a weapons program through to the final production and surveillance stages. This report discusses a concept investing key leveraging technologies and operational concepts combined with prototype tester-development experiences and practical lessons learned gleaned from past weapons programs.

  6. Cyrenaican platform: structure, stratigraphy, and exploration play concepts

    SciTech Connect

    Ross, C.M.; Zegaar, M.N.

    1985-02-01

    The structural and stratigraphic history of the Cyrenaican platform of eastern Libya is closely related to that of both the Sirte basin and the Western Desert of Egypt. At the end of the Paleozoic Hercynian orogeny, this area comprised the eastern end of the Sirte arch, the precursor of the Sirte basin. When the arch collapsed in the mid-Cretaceous, initiating the Sirte basin, the Cyrenaican area remained relatively high. A northwest-southeast trending high, the Gabboub arch, formed on the platform in the early Mesozoic, dividing the region into three areas: the high itself, a deep on the southwestern flank related to the Sirte basin, and a deep on the northeastern flank, which plunges into the offshore and appears to relate to the downwarped offshore area of the Western Desert of Egypt. Sediments of every age, except Triassic, are found in Cyrenaica. Paleozoic sediments are composed primarily of quartzitic sandstones and shales with lesser amounts of limestone, dolomites, and anhydrites. Mesozoic sediments are a mixture of clastics and carbonates. Cenozoic sediments are predominantly limestones, dolomites, and anhydrites with some sandstones and shales. Environments of deposition range from continental to deep marine. The Cyrenaican area has not been heavily explored and, until recently, no commercial hydrocarbons were found. Drilling on surface structures of some of the first wells in Libya resulted in one Devonian gas well. A reported 5600 BOPD Cretaceous discovery offshore Benghazi in mid-1984 demonstrates that hydrocarbon potential exists where thick sediments have been preserved.

  7. Micro borehole drilling platform

    SciTech Connect

    1996-10-01

    This study by CTES, L.C. meets two main objectives. First, evaluate the feasibility of using coiled tubing (CT) to drill 1.0 inches-2.5 inches diameter directional holes in hard rocks. Second, develop a conceptual design for a micro borehole drilling platform (MBDP) meeting specific size, weight, and performance requirements. The Statement of Work (SOW) in Appendix A contains detailed specifications for the feasibility study and conceptual design.

  8. Secure Sensor Platform

    Energy Science and Technology Software Center (ESTSC)

    2010-08-25

    The Secure Sensor Platform (SSP) software provides a framework of functionality to support the development of low-power autonomous sensors for nuclear safeguards. This framework provides four primary functional blocks of capabilities required to implement autonomous sensors. The capabilities are: communications, security, power management, and cryptography. Utilizing this framework establishes a common set of functional capabilities for seamless interoperability of any sensor based upon the SSP concept.

  9. HPC - Platforms Penta Chart

    SciTech Connect

    Trujillo, Angelina Michelle

    2015-10-08

    Strategy, Planning, Acquiring- very large scale computing platforms come and go and planning for immensely scalable machines often precedes actual procurement by 3 years. Procurement can be another year or more. Integration- After Acquisition, machines must be integrated into the computing environments at LANL. Connection to scalable storage via large scale storage networking, assuring correct and secure operations. Management and Utilization – Ongoing operations, maintenance, and trouble shooting of the hardware and systems software at massive scale is required.

  10. The Prodiguer Messaging Platform

    NASA Astrophysics Data System (ADS)

    Greenslade, Mark; Denvil, Sebastien; Raciazek, Jerome; Carenton, Nicolas; Levavasseur, Guillame

    2014-05-01

    CONVERGENCE is a French multi-partner national project designed to gather HPC and informatics expertise to innovate in the context of running French climate models with differing grids and at differing resolutions. Efficient and reliable execution of these models and the management and dissemination of model output (data and meta-data) are just some of the complexities that CONVERGENCE aims to resolve. The Institut Pierre Simon Laplace (IPSL) is responsible for running climate simulations upon a set of heterogenous HPC environments within France. With heterogeneity comes added complexity in terms of simulation instrumentation and control. Obtaining a global perspective upon the state of all simulations running upon all HPC environments has hitherto been problematic. In this presentation we detail how, within the context of CONVERGENCE, the implementation of the Prodiguer messaging platform resolves complexity and permits the development of real-time applications such as: 1. a simulation monitoring dashboard; 2. a simulation metrics visualizer; 3. an automated simulation runtime notifier; 4. an automated output data & meta-data publishing pipeline; The Prodiguer messaging platform leverages a widely used open source message broker software called RabbitMQ. RabbitMQ itself implements the Advanced Message Queue Protocol (AMPQ). Hence it will be demonstrated that the Prodiguer messaging platform is built upon both open source and open standards.

  11. The Prodiguer Messaging Platform

    NASA Astrophysics Data System (ADS)

    Denvil, S.; Greenslade, M. A.; Carenton, N.; Levavasseur, G.; Raciazek, J.

    2015-12-01

    CONVERGENCE is a French multi-partner national project designed to gather HPC and informatics expertise to innovate in the context of running French global climate models with differing grids and at differing resolutions. Efficient and reliable execution of these models and the management and dissemination of model output are some of the complexities that CONVERGENCE aims to resolve.At any one moment in time, researchers affiliated with the Institut Pierre Simon Laplace (IPSL) climate modeling group, are running hundreds of global climate simulations. These simulations execute upon a heterogeneous set of French High Performance Computing (HPC) environments. The IPSL's simulation execution runtime libIGCM (library for IPSL Global Climate Modeling group) has recently been enhanced so as to support hitherto impossible realtime use cases such as simulation monitoring, data publication, metrics collection, simulation control, visualizations … etc. At the core of this enhancement is Prodiguer: an AMQP (Advanced Message Queue Protocol) based event driven asynchronous distributed messaging platform. libIGCM now dispatches copious amounts of information, in the form of messages, to the platform for remote processing by Prodiguer software agents at IPSL servers in Paris. Such processing takes several forms: Persisting message content to database(s); Launching rollback jobs upon simulation failure; Notifying downstream applications; Automation of visualization pipelines; We will describe and/or demonstrate the platform's: Technical implementation; Inherent ease of scalability; Inherent adaptiveness in respect to supervising simulations; Web portal receiving simulation notifications in realtime.

  12. "Platform switching": serendipity.

    PubMed

    Kalavathy, N; Sridevi, J; Gehlot, Roshni; Kumar, Santosh

    2014-01-01

    Implant dentistry is the latest developing field in terms of clinical techniques, research, material science and oral rehabilitation. Extensive work is being done to improve the designing of implants in order to achieve better esthetics and function. The main drawback with respect to implant restoration is achieving good osseointegration along with satisfactory stress distribution, which in turn will improve the prognosis of implant prosthesis by reducing the crestal bone loss. Many concepts have been developed with reference to surface coating of implants, surgical techniques for implant placement, immediate and delayed loading, platform switching concept, etc. This article has made an attempt to review the concept of platform switching was in fact revealed accidentally due to the nonavailability of the abutment appropriate to the size of the implant placed. A few aspect of platform switching, an upcoming idea to reduce crestal bone loss have been covered. The various methods used for locating and preparing the data were done through textbooks, Google search and related articles. PMID:24992863

  13. Mesozoic to Cenozoic paleogeography and tectonics of the Apulian platform

    SciTech Connect

    Yilmaz, P.O.; Norton, I.O.; Chuchla, R.J.

    1995-08-01

    In this study we utilize the tectonic history of the Apulian platform to constrain understanding of sedimentary basins of the Adriatic. Apulian basement consists of Hercynian metamorphic rocks. Early Mesozoic rifting created a distinct platform-basin geometry which focused Mesozoic hydrocarbon systems. Troughs with terrigenous fill are bordered by platforms with shallow water carbonates. Source rock facies are found in the troughs, while reservoir rocks are in the platforms. Apulia separated from Africa in Jurassic time, and converged with Europe through Cretaceous to Paleocene time. Collision with Europe started in Eocene time. The eastern flank of Apulia collided with Europe in the Dinaride region along the Vardar suture. Deformation continued into Oligocene time, with an associated foredeep. The western flank of Apulia did not collide with Europe, instead, it deformed internally as a result of Oligocene to Miocene convergence of Corsica and Sardinia. The resulting Apennine fold and thrust belt formed a foredeep in the Adriatic. Deformation continues to present day, as Africa and Europe converge. This foredeep plays a significant role in source rock maturation and trap formation.

  14. Genesis of selected Triassic basins on the Italian peninsula: Their origin and hydrocarbon potential

    SciTech Connect

    Rigo de Righi, L.L.

    1990-01-01

    The paleogeographic evolution of the southern Alpine Lombardy Basin, the Central Adriatic Pescara Basin, and the Sicilian Ragusa Basin in Italy document the depositional and structural evolution of the Mesozoic Apulian Plate. These Mesozoic basins formed as a response to the Jurassic opening of the Tethyan Ocean. Due to their respective position in relation to the Mesozoic Tethyan spreading center, each of the three basins formed with unique structural entities. The Mesozoic paleogeographic history of the Lombardy Basin suggests that it initially formed a continental arc basin on the northern margin of the Apulian Plate. As Tethyan rifting progressed, the basin subsequently evolved into an Early Jurassic passive continental rift margin. The Pescara Basin, with its central Apulian paleogeographic location, developed as a Tethyan rift basin in the Jurassic. The Ragusa Basin represents Mesozoic developments along the southern portion of the Apulian Plate. Depositionally, paleohighs and periods of tectonic stability are typically represented by extensive carbonate platform deposits. Within these carbonate platforms incipient stages of faulting are characterized by shallow anoxic lagoonal deposits. These structurally weak ones were subsequently incorporated within the Tethyan Jurassic rift. Synrift deposits are predominantly characterized by thick sequences of Jurassic and Cretaceous pelagic carbonates.

  15. Eclipse Parallel Tools Platform

    Energy Science and Technology Software Center (ESTSC)

    2005-02-18

    Designing and developing parallel programs is an inherently complex task. Developers must choose from the many parallel architectures and programming paradigms that are available, and face a plethora of tools that are required to execute, debug, and analyze parallel programs i these environments. Few, if any, of these tools provide any degree of integration, or indeed any commonality in their user interfaces at all. This further complicates the parallel developer's task, hampering software engineering practices,more » and ultimately reducing productivity. One consequence of this complexity is that best practice in parallel application development has not advanced to the same degree as more traditional programming methodologies. The result is that there is currently no open-source, industry-strength platform that provides a highly integrated environment specifically designed for parallel application development. Eclipse is a universal tool-hosting platform that is designed to providing a robust, full-featured, commercial-quality, industry platform for the development of highly integrated tools. It provides a wide range of core services for tool integration that allow tool producers to concentrate on their tool technology rather than on platform specific issues. The Eclipse Integrated Development Environment is an open-source project that is supported by over 70 organizations, including IBM, Intel and HP. The Eclipse Parallel Tools Platform (PTP) plug-in extends the Eclipse framwork by providing support for a rich set of parallel programming languages and paradigms, and a core infrastructure for the integration of a wide variety of parallel tools. The first version of the PTP is a prototype that only provides minimal functionality for parallel tool integration of a wide variety of parallel tools. The first version of the PTP is a prototype that only provides minimal functionality for parallel tool integration, support for a small number of parallel architectures

  16. The DAΦNE-Light Facility

    NASA Astrophysics Data System (ADS)

    Burattini, Emilio; Cinque, Gianfelice; Dabagov, Sultan; Grilli, Antonio; Marcelli, Augusto; Monti, Francesca; Pace, Elisabetta; Piccinini, Massimo; Raco, Agostino

    2004-05-01

    The new Synchrotron Radiation facility at Frascati exploits the intense photon emission from DAΦNE, the 0,51 GeV storage ring circulating over 1 A of electrons. Among the three beamlines commissioned, the Synchrotron INfrared Beamline At Daφne (SINBAD) is fully operational by a brilliant SR beam spanning the entire IR. Recently, the soft X-ray beamline has been characterized and, once implemented the double-crystal monocromator, X-ray Absorption Spectroscopy is applied on material standards in the distinguishing energy region below 4 keV. An UltraViolet line, presently dedicated to photobiology dosimetry, has also given first results on cell irradiation in the UVB band.

  17. The DA{phi}NE-Light Facility

    SciTech Connect

    Burattini, Emilio; Cinque, Gianfelice; Dabagov, Sultan; Grilli, Antonio; Marcelli, Augusto; Pace, Elisabetta; Piccinini, Massimo; Raco, Agostino; Monti, Francesca

    2004-05-12

    The new Synchrotron Radiation facility at Frascati exploits the intense photon emission from DA{phi}NE, the 0,51 GeV storage ring circulating over 1 A of electrons. Among the three beamlines commissioned, the Synchrotron INfrared Beamline At Da{phi}ne (SINBAD) is fully operational by a brilliant SR beam spanning the entire IR. Recently, the soft X-ray beamline has been characterized and, once implemented the double-crystal monocromator, X-ray Absorption Spectroscopy is applied on material standards in the distinguishing energy region below 4 keV. An UltraViolet line, presently dedicated to photobiology dosimetry, has also given first results on cell irradiation in the UVB band.

  18. Status of KM3NeT

    NASA Astrophysics Data System (ADS)

    Riccobene, G.

    2016-07-01

    The recent observation of cosmic neutrinos by IceCube has pushed the quest towards the identification of cosmic sources of high-energy particles. The KM3NeT Collaboration is now ready to launch the massive construction of detection units to be installed in deep sea to build a km-cubic size neutrino telescope. The main elements of the detector, the status of the project and the expected perfomances are briefly reported.

  19. CLIPS on the NeXT computer

    NASA Technical Reports Server (NTRS)

    Charnock, Elizabeth; Eng, Norman

    1990-01-01

    This paper discusses the integration of CLIPS into a hybrid expert system neural network AI tool for the NeXT computer. The main discussion is devoted to the joining of these two AI paradigms in a mutually beneficial relationship. We conclude that expert systems and neural networks should not be considered as competing AI implementation methods, but rather as complimentary components of a whole.

  20. Neotectonic reactivation of shear zones and implications for faulting style and geometry in the continental margin of NE Brazil

    NASA Astrophysics Data System (ADS)

    Bezerra, F. H. R.; Rossetti, D. F.; Oliveira, R. G.; Medeiros, W. E.; Neves, B. B. Brito; Balsamo, F.; Nogueira, F. C. C.; Dantas, E. L.; Andrades Filho, C.; Góes, A. M.

    2014-02-01

    The eastern continental margin of South America comprises a series of rift basins developed during the breakup of Pangea in the Jurassic-Cretaceous. We integrated high resolution aeromagnetic, structural and stratigraphic data in order to evaluate the role of reactivation of ductile, Neoproterozoic shear zones in the deposition and deformation of post-rift sedimentary deposits in one of these basins, the Paraíba Basin in northeastern Brazil. This basin corresponds to the last part of the South American continent to be separated from Africa during the Pangea breakup. Sediment deposition in this basin occurred in the Albian-Maastrichtian, Eocene-Miocene, and in the late Quaternary. However, our investigation concentrates on the Miocene-Quaternary, which we consider the neotectonic period because it encompasses the last stress field. This consisted of an E-W-oriented compression and a N-S-oriented extension. The basement of the basin forms a slightly seaward-tilted ramp capped by a late Cretaceous to Quaternary sedimentary cover ~ 100-400 m thick. Aeromagnetic lineaments mark the major steeply-dipping, ductile E-W- to NE-striking shear zones in this basement. The ductile shear zones mainly reactivated as strike-slip, normal and oblique-slip faults, resulting in a series of Miocene-Quaternary depocenters controlled by NE-, E-W-, and a few NW-striking faults. Faulting produced subsidence and uplift that are largely responsible for the present-day morphology of the valleys and tablelands in this margin. We conclude that Precambrian shear zone reactivation controlled geometry and orientation, as well as deformation of sedimentary deposits, until the Neogene-Quaternary.

  1. Passive margins: U.S. Geological Survey Line 19 across the Georges Bank basin

    USGS Publications Warehouse

    Klitgord, Kim D.; Schlee, John S.; Grow, John A.

    1987-01-01

    Georges Bank is a shallow part of the Atlantic continental shelf southeast of New England (Emery and Uchupi, 1972, 1984). This bank, however, is merely the upper surface of several sedimentary basins overlying a block-faulted basement of igneous and metamorphic crystalline rock. Sedimentary rock forms a seaward-thickening cover that has accumulated in one main depocenter and several ancillary depressions, adjacent to shallow basement platforms of paleozoic and older crystalline rock. Georges Bank basin contains a thickness of sedimentary rock greater than 10 km, whereas the basement platforms that flank the basin are areas of thin sediment accumulation (less than 5 km).

  2. UCB-NE-101 user's manual

    SciTech Connect

    Lee, W.W.L.

    1989-02-01

    The purpose of this manual is to provide users of UCB-NE-101 with the information necessary to use UCB-NE-101 effectively. UCB-NE-101 calculates the concentration of solubility-limited species as a function of space and time and its mass flux rates from a waste sphere buried in a nuclear waste repository in water-saturated rock. The waste is surrounded by one type of rock, and some distance away, there is another type of rock. The inner layer of rock can be a backfill around a nuclear waste package and the outer layer the natural rock. The mass flux calculated is at the interface of the two layers. The species concentration calculated is in the inner layer. A constant concentration of the species, usually the solubility, is specified at the waste sphere/inner layer interface. Dissolution and transport is governed by the solubility of the species, and diffusion in the porous media. 1 ref., 1 fig.

  3. 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.

  4. The North Pyrenean Aquitaine Basin, France: Evolution and hydrocarbons

    SciTech Connect

    Bourrouilh, R.; Richert, J.P.; Zolnaie, G.

    1995-06-01

    The Mesozoic-Tertiary Aquitaine basin overlaps the Aquitaine block and the northern edge of the Iberian margin. Both units are situated in the southwesternmost part of the European Continent. The Aquitaine shelf is a stable platform overlying a relatively thin crustal segment; it underwent extensional block faulting and many of its folded structures are related to salt tectonism. The Iberian block is a thicker lithospheric unit that acted as a buttress. At the junction of these two structural domains the South Aquitaine or North Pyrenean area developed, where crustal stretching, rifting, wrenching, and orogenic compression were maximal from the Mesozoic to the Tertiary. The history of the basin has been a suite of rifting attempts, in the context of the progressive opening of the Bay of Biscay, which never completely succeeded. The relative plate motions and the later convergence led, nevertheless, to the formation of the Aquitaine basin and to the emergence of the Pyrenean fold belt. The Mesozoic-Tertiary sedimentary infill of the basin is mostly marine, with thick evaporates, stable platform carbonates, subsiding platform shaly-calcareous deposits, and a characteristic, diachronous turbiditic (flysch) and molasse complex. Events during the basin-forming, extensional, and translational periods contributed more to the generation of the hydrocarbon accumulations than did the effects of the subsequent compressive structural regime. The latter, however, may have enhanced thermal flow and, thus, maturation of hydrocarbon source rocks.

  5. The Geohazards Exploitation Platform

    NASA Astrophysics Data System (ADS)

    Laur, Henri; Casu, Francesco; Bally, Philippe; Caumont, Hervé; Pinto, Salvatore

    2016-04-01

    The Geohazards Exploitation Platform, or Geohazards TEP (GEP), is an ESA originated R&D activity of the EO ground segment to demonstrate the benefit of new technologies for large scale processing of EO data. This encompasses on-demand processing for specific user needs, systematic processing to address common information needs of the geohazards community, and integration of newly developed processors for scientists and other expert users. The platform supports the geohazards community's objectives as defined in the context of the International Forum on Satellite EO and Geohazards organised by ESA and GEO in Santorini in 2012. The GEP is a follow on to the Supersites Exploitation Platform (SSEP) an ESA initiative to support the Geohazards Supersites & Natural Laboratories initiative (GSNL). Today the GEP allows to exploit 70+ Terabyte of ERS and ENVISAT archive and the Copernicus Sentinel-1 data available on line. The platform has already engaged 22 European early adopters in a validation activity initiated in March 2015. Since September, this validation has reached 29 single user projects. Each project is concerned with either integrating an application, running on demand processing or systematically generating a product collection using an application available in the platform. The users primarily include 15 geoscience centres and universities based in Europe: British Geological Survey (UK), University of Leeds (UK), University College London (UK), ETH University of Zurich (CH), INGV (IT), CNR-IREA and CNR-IRPI (IT), University of L'Aquila (IT), NOA (GR), Univ. Blaise Pascal & CNRS (FR), Ecole Normale Supérieure (FR), ISTERRE / University of Grenoble-Alpes (FR). In addition, there are users from Africa and North America with the University of Rabat (MA) and the University of Miami (US). Furthermore two space agencies and four private companies are involved: the German Space Research Centre DLR (DE), the European Space Agency (ESA), Altamira Information (ES

  6. Sterile Neutrino Searches in MiniBooNE and MicroBooNE

    SciTech Connect

    Ignarra, Christina M.

    2014-09-01

    Tension among recent short baseline neutrino experiments has pointed toward the possible need for the addition of one or more sterile (non-interacting) neutrino states into the existing neutrino oscillation framework. This thesis first presents the motivation for sterile neutrino models by describing the short-baseline anomalies that can be addressed with them. This is followed by a discussion of the phenomenology of these models. The MiniBooNE experiment and results are then described in detail, particularly the most recent antineutrino analysis. This will be followed by a discussion of global fits to world data, including the anomalous data sets. Lastly, future experiments will be addressed, especially focusing on the MicroBooNE experiment and light collection studies. In particular, understanding the degradation source of TPB, designing the TPB-coated plates for MicroBooNE and developing lightguide collection systems will be discussed. We find an excess of events in the MiniBooNE antineutrino mode results consistent with the LSND anomaly, but one that has a different energy dependence than the low-energy excess reported in neutrino mode. This disagreement creates tension within global fits which include up to three sterile neutrinos. The low-energy excess will be addressed by the MicroBooNE experiment, which is expected to start taking data in early 2015. Tension among existing experiments calls for additional, more decisive future experiments.

  7. Modeling of the atomic Ne laser in He/Ne/Ar gas mixtures

    SciTech Connect

    Jong, W.; Kushner, S.; Kushner, M.J.

    1992-12-01

    The high pressure atomic Ne laser operates on 4 visible transitions between the 3p and 3s manifolds. There has been renewed interest in this laser due to demonstrated high efficiency lasing at 585 nm in e-beam and fission fragment excited plasmas. A comprehensive computer model for the Ne laser in He/Ne/Ar mixtures has been developed to examine excitation mechanisms. The authors found that direct excitation of the 3p manifold by dissociative recombination of Ne{sub 2}{sup +} is the likely pumping mechanism, while state-selective Penning reactions dominantly relax the lower levels. Comparisons to experiments performed on a short pulsed e-beam excited laser showed that the electron temperature in the afterglow is determined by a slow relaxation of excited states in Ar. Oscillation does not occur until these manifolds are depleted, and the electron temperature falls. Scaling laws for the Ne laser at low pump powers, as obtained using fission fragment excitation, will be discussed.

  8. Évolution géodynamique de l'Indonésie orientale, de l'Éocène au Pliocène

    NASA Astrophysics Data System (ADS)

    Villeneuve, Michel; Réhault, Jean-Pierre; Cornée, Jean-Jacques; Honthaas, Christian; Gunawan c, Wahyu; le Groupe Géobanda

    1998-09-01

    Eastern Indonesia belongs to a convergent zone between the Asiatic, Australian and Pacific plates. A lot of synthetic papers have been devoted to this very technically active area. Our new geodynamic reconstruction takes into account a six year period of scientific cooperation between France and Indonesia. This cooperation provided various geological data. The hypothesis presented here is based on the geological evolution of lour small commentai blocks (two of which appear for the first time: the Banda und l.ucipara blocks) trapped by the convergence of the threemain plates. The main steps are successively: the Upper Eocene to Oligocene. during which the Banda block collided with the south east asiatic margin in Sulawesi: the Lower Miocene, during which the l.iicipara block (including (he Tukang IJesi platform) collided with the Banda block itself, mainly in the Buton area: the Upper Miocene, which is a period of large extensional regime. Most of the basins inside the Banda area opened at that time (North Banda Basin, South Banda Basin, Savu Basin, etc.). The next interesting period is the Upper Pliocene, which occurred after the main collisions between the Australian continental block and the Banda and Irian Java blocks. The Bangai Sula block collided with the eastern part of Sulawesi at the end of the Lower Pliocene.

  9. Automated Platform Management System Scheduling

    NASA Technical Reports Server (NTRS)

    Hull, Larry G.

    1990-01-01

    The Platform Management System was established to coordinate the operation of platform systems and instruments. The management functions are split between ground and space components. Since platforms are to be out of contact with the ground more than the manned base, the on-board functions are required to be more autonomous than those of the manned base. Under this concept, automated replanning and rescheduling, including on-board real-time schedule maintenance and schedule repair, are required to effectively and efficiently meet Space Station Freedom mission goals. In a FY88 study, we developed several promising alternatives for automated platform planning and scheduling. We recommended both a specific alternative and a phased approach to automated platform resource scheduling. Our recommended alternative was based upon use of exactly the same scheduling engine in both ground and space components of the platform management system. Our phased approach recommendation was based upon evolutionary development of the platform. In the past year, we developed platform scheduler requirements and implemented a rapid prototype of a baseline platform scheduler. Presently we are rehosting this platform scheduler rapid prototype and integrating the scheduler prototype into two Goddard Space Flight Center testbeds, as the ground scheduler in the Scheduling Concepts, Architectures, and Networks Testbed and as the on-board scheduler in the Platform Management System Testbed. Using these testbeds, we will investigate rescheduling issues, evaluate operational performance and enhance the platform scheduler prototype to demonstrate our evolutionary approach to automated platform scheduling. The work described in this paper was performed prior to Space Station Freedom rephasing, transfer of platform responsibility to Code E, and other recently discussed changes. We neither speculate on these changes nor attempt to predict the impact of the final decisions. As a consequence some of our

  10. Tension leg platform system

    SciTech Connect

    Burns, R.B.

    1983-12-20

    A tension leg platform system for use in drilling wellbores into the floor of an offshore body of water. Includes in the system is a buoyancy control vessel having a plurality of pull down cables attached thereto which extend to the ocean floor. A plurality of spaced apart anchors disposed at the ocean floor are positioned to receive the lower ends of the respective pull down cables. A submergible hull slidably engages the respective hold down cables such that the hull can be controllably lowered to the ocean floor whereby a canopy carried on the hull will cover an uncontrollably flowing well to conduct the effluent to the water's surface.

  11. Reinforced concrete offshore platform

    SciTech Connect

    Martyshenko, J.P.; Martyshenko, S.J.; Kotelnikov, J.S.; Kutukhtin, E.G.; Petrosian, M.S.; Ilyasova, N.I.; Volkov, J.S.; Vardanian, A.M.

    1987-10-20

    A reinforced concrete offshore platform is described comprising a honeycomb foundation (A), a supporting structure (B) and an above-surface section (C) carrying appropriate equipment. The honeycomb foundation (A) and the supporting structure (B) are made of prefabricated reinforced concrete elements which are polyhedral hollow prisms arranged with gaps between the external sides thereof and joined by a system of prestressed vertical diaphragm walls and horizontal diaphragm walls formed by pre-tensioning reinforcing bars placed in the gaps between the faces of the prisms and casting in-situ the gaps later on.

  12. Dating the birth, growth and death of Miocene carbonate platforms in the South China Sea, Central Luconia Province, Sarawak

    NASA Astrophysics Data System (ADS)

    Ting, K.; Pierson, B. J.; Pubellier, M.; Menier, D.; Warrlich, G.; Jamaludin, S.

    2012-12-01

    The regional distribution, respective location of the Miocene carbonate platforms of Central Luconia and their internal architecture suggest a development initiated and influenced by the late Neogene evolution of the South China Sea. A first regional fragmentation of an extensive carbonate bank probably took place in the early Mid-Miocene (20-15 Ma) period. Series of NE-SW and NW-SE lineaments separating isolated carbonate platforms suggest this regional fragmentation. This event led to the growth of a number of relatively closely spaced isolated platforms, in what is referred to as the "build-up" stage. A second event or series of events probably occurred during the 15-12Ma period, and may have been linked to the last propagator-associated rifting phase that was specific to the southern part of the South China Sea. It is possible that it triggered gravity-induced faulting, which broke up individual isolated platforms. The movements that affected the platforms during this period were subtle and, although platform fragmentation occurred, most platforms were able to heal. A third event, characterized by further fragmentation and rotation of individual platforms may have resulted from gravitational tectonics during the Late Miocene (12-7Ma) period. The slight rotation of individual platforms that occurred during this period resulted in a significant back-stepping of the margins and contraction of the platforms, caused by partial drowning of the subsided part of the platform in what is referred to as the "build-in" stage.

  13. Masses and Charge Radii of {sup 17-22}Ne and the Two-Proton-Halo Candidate {sup 17}Ne

    SciTech Connect

    Geithner, W.; Kappertz, S.; Keim, M.; Neugart, R.; Wilbert, S.; Neff, T.; Feldmeier, H.; Herfurth, F.; Yazidjian, C.; Audi, G.; Guenaut, C.; Lunney, D.; Blaum, K.; George, S.; Delahaye, P.; Kellerbauer, A.; Kowalska, M.; Herlert, A.; Kluge, H.-J.; Lievens, P.

    2008-12-19

    High-precision mass and charge radius measurements on {sup 17-22}Ne, including the proton-halo candidate {sup 17}Ne, have been performed with Penning trap mass spectrometry and collinear laser spectroscopy. The {sup 17}Ne mass uncertainty is improved by factor 50, and the charge radii of {sup 17-19}Ne are determined for the first time. The fermionic molecular dynamics model explains the pronounced changes in the ground-state structure. It attributes the large charge radius of {sup 17}Ne to an extended proton configuration with an s{sup 2} component of about 40%. In {sup 18}Ne the smaller radius is due to a significantly smaller s{sup 2} component. The radii increase again for {sup 19-22}Ne due to cluster admixtures.

  14. Evolution history of the Heuksan Basin, a continental rift basin in the Yellow Sea

    NASA Astrophysics Data System (ADS)

    Yoon, S.; Kim, G.; Park, M.

    2011-12-01

    This study focuses on the establishment of evolutionary framework of the Heuksan Basin regions located on the southwestern part of the concession block III of the Korean offshore in the Yellow Sea. Three fault-bounded sub-basins (SB-1, SB-2, and SB-3) are recognized on the basis of topographic map of acoustic basement, which are generally in asymmetric half-graben geometry trending WNW-ESE. The axial lengths of the sub-basins are generally less than 80 km in axial length and 20 km in width. The acoustic basement occurs at around 0.6 to 0.8 s twt bsl in generally, locally much deeper at about 2.4 s twt bsl in the deepest part of the sub-basins, and it is correlated with the Upper Paleozoic to Lower Mesozoic sequence of thick micritic limestones overlying major clastic cycles with thin coals. In the sedimentary succession, two erosional surfaces (ES-1 and ES-2) are identified based on the interpretation of truncated geometries and lap-out patterns, which provide three stratigraphic units (SU-1, SU-2, and SU-3). During the Late Cretaceous to Oligocene the basin had opened by NE-SW extension or transtension. By this tectonic movement, WNW-ESE trending sub-basins with an array of listric normal faults were formed. Until the cessation of the opening, the wedge-shaped syn-rift unit (SU-1) infilled the depressions of the rift basins. In the Late Oligocene to Early Miocene time the extensional or transtensional tectonic movement of the Heuksan Basin region was aborted or partly inverted into compressional or transpressional regime. By this tectonic movement, acoustic basement and syn-rift unit (SU-1) might have uplifted, and have experienced a regional planation process. Topographic irregularities were removed by erosion and infilling process. SU-1 might have formed during this period in the localized topographic lows of the basins. Subaerial to shallow-marine planation process on the slightly folded and uplifted SU-1during subsequent tectonic inversion in the Early Miocene

  15. Open systems storage platforms

    NASA Technical Reports Server (NTRS)

    Collins, Kirby

    1992-01-01

    The building blocks for an open storage system includes a system platform, a selection of storage devices and interfaces, system software, and storage applications CONVEX storage systems are based on the DS Series Data Server systems. These systems are a variant of the C3200 supercomputer with expanded I/O capabilities. These systems support a variety of medium and high speed interfaces to networks and peripherals. System software is provided in the form of ConvexOS, a POSIX compliant derivative of 4.3BSD UNIX. Storage applications include products such as UNITREE and EMASS. With the DS Series of storage systems, Convex has developed a set of products which provide open system solutions for storage management applications. The systems are highly modular, assembled from off the shelf components with industry standard interfaces. The C Series system architecture provides a stable base, with the performance and reliability of a general purpose platform. This combination of a proven system architecture with a variety of choices in peripherals and application software allows wide flexibility in configurations, and delivers the benefits of open systems to the mass storage world.

  16. Cots Correlator Platform

    NASA Astrophysics Data System (ADS)

    Schaaf, Kjeld; Overeem, Ruud

    2004-06-01

    Moore’s law is best exploited by using consumer market hardware. In particular, the gaming industry pushes the limit of processor performance thus reducing the cost per raw flop even faster than Moore’s law predicts. Next to the cost benefits of Common-Of-The-Shelf (COTS) processing resources, there is a rapidly growing experience pool in cluster based processing. The typical Beowulf cluster of PC’s supercomputers are well known. Multiple examples exists of specialised cluster computers based on more advanced server nodes or even gaming stations. All these cluster machines build upon the same knowledge about cluster software management, scheduling, middleware libraries and mathematical libraries. In this study, we have integrated COTS processing resources and cluster nodes into a very high performance processing platform suitable for streaming data applications, in particular to implement a correlator. The required processing power for the correlator in modern radio telescopes is in the range of the larger supercomputers, which motivates the usage of supercomputer technology. Raw processing power is provided by graphical processors and is combined with an Infiniband host bus adapter with integrated data stream handling logic. With this processing platform a scalable correlator can be built with continuously growing processing power at consumer market prices.

  17. Platform for Action: update.

    PubMed

    1995-01-01

    The Center for Women's Global Leadership (CWGL) has collaborated in the preparation of amendments and strategies designed to withstand the challenges being posed to the Platform for Action of the Fourth World Conference on Women. Specific challenges include the inappropriate use of the word "universal" to modify "human rights." This implies that some human rights are less than universal. The strategy proposed is to accept the use of the word "universal" in this context only when it affirms principles of universality contained in the Vienna Programme of Action and not where its use would restrict the rights to which women are entitled. A second concern is over the use of the word "equity" rather than "equality" when referring to gender relations. The use of these terms will be carefully monitored to insure that "equity" not be used to undermine the principle of gender equality. The third concern is the efforts of some governments to hinder the integration of women's human rights throughout the UN system. Such efforts will be opposed. Fourth, the CWGL will seek the inclusion of language which recognizes the barriers that different groups of women face when trying to secure their rights. Finally, the CWGL will propose inclusion of language recognizing and protecting sexual orientation rights. The CWGL is also going to work to translate the abstract language of the Platform for Action into political organizing potential to insure that governments will follow through on their agreements. PMID:12346441

  18. Emplacement of magma in sedimentary basins

    NASA Astrophysics Data System (ADS)

    Malthe-Sorenssen, A.; Planke, S.

    2002-12-01

    Sheet-like intrusive complexes are commonly present in sedimentary basins on rifted volcanic margins. Such sill complexes have important impact on petroleum maturation, migration and trapping. We are currently completing an integrated seismic, field and theoretical study on the petroleum implications of sill intrusions. One aspect of this study has been to get new understanding of the magma emplacement processes based on integrated numerical modeling and geophysical/geological mapping activities. Extensive sill complexes have been identified and mapped in the NE Atlantic and Karoo basins based on seismic, borehole, remote sensing and field data. Early Tertiary intrusive complexes are present in the Voring and More basins offshore mid-Norway. Similar sill complexes are exposed onshore in Cretaceous to Permian age sedimentary sequences on the conjugate central-east Greenland margin. A voluminous Jurassic age intrusive complex is well exposed in the Permian to Jurassic Karoo basin as the erosionally strong dolerites form an impressive mountainous landscape in large parts of South Africa. The sheet intrusions are found at paleodepths of 0-6 km. Deep intrusions are generally long and smooth, whereas shallow intrusions are rough, transgressive and commonly saucer-shaped. Saucer-shaped intrusions are present in unstructured basin segments. The diameter of the saucers increases with depth. Structured basin segments are characterized by a variety of sill complex geometries. The intrusions generally mimic the basin structure. In nature, magma is emplaced in internally pressurized, planar cracks. The emplacement process is controlled by the local stress field and complex interactions of buoyancy forces, host rock resistance to fracture, elastic deformation of country rock, magma hydrostatic pressure and fluctuating magma pressure, magma viscosity and weight of overburden. We have developed a discrete element model to study the emplacement process. Results from the modeling

  19. Reserves in western basins

    SciTech Connect

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

    1992-06-01

    This project requires generation of producible tight gas sand reserve estimates for three western basins. The requirement is to perform such reserve estimates using industry accepted practices so that results will have high credibility and acceptance by the oil and gas industry. The ultimate goal of the project is to encourage development of the tight gas formation by industry through reduction of the technical and economic risks of locating, drilling and completing commercial gas wells. The three geological basins selected for study are the Greater Green River Basin, Uinta Basin and Piceance Basin, located in the Colorado, Utah and Wyoming Rocky Mountain region.

  20. Reserves in western basins

    SciTech Connect

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

    1992-01-01

    This project requires generation of producible tight gas sand reserve estimates for three western basins. The requirement is to perform such reserve estimates using industry accepted practices so that results will have high credibility and acceptance by the oil and gas industry. The ultimate goal of the project is to encourage development of the tight gas formation by industry through reduction of the technical and economic risks of locating, drilling and completing commercial gas wells. The three geological basins selected for study are the Greater Green River Basin, Uinta Basin and Piceance Basin, located in the Colorado, Utah and Wyoming Rocky Mountain region.

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

    NASA Astrophysics Data System (ADS)

    Lee, Eun Young; Wagreich, Michael

    2016-04-01

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

  2. Geosynchronous platform definition study. Volume 5: Geosynchronous platform synthesis

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The development is described of the platform configurations, support subsystems, mission equipment, and servicing concepts. A common support module is developed; subsystem concepts are traded off; data relay, TDRS, earth observational, astro-physics, and advanced navigation and traffic control mission equipment concepts are postulated; and ancillary equipment required for delivery and on-orbit servicing interfaces with geosynchronous platforms is grossly defined. The general approach was to develop a platform concept capable of evolving through three on-orbit servicing modes: remote, EVA, and shirtsleeve. The definition of the equipment is to the assembly level. Weight, power, and volumetric data are compiled for all the platforms.

  3. Irregular plate boundary controls on Foreland Basin sedimentation (Miocene, Kahramanmaraş Foreland Basin, SE Turkey)

    NASA Astrophysics Data System (ADS)

    Gül, Murat; Gürbüz, Kemal; Cronin, Bryan T.

    2015-11-01

    The northern movement of the Arabian Plate led to the development of a compressional regime in the south-eastern part of Turkey after the Late Cretaceous. The collision of the Arabian Plate with the Anatolide-Taurides Platform and subsequent development of the Kahramanmaraş Foreland Basin at the beginning of the Miocene evolved as a result of this movement. An irregular plate geometry or promontory of the Arabian Plate caused partitioning of the plate margin (precollision-collision-postcollision). This irregular plate boundary was delimited by western and northern boundary faults and an interior basin fault. The NW-oriented small wedge top basins on the overlying Anatolide-Taurides Platform obliquely cut through the foredeep basin. The region (across the wedge top basin) on the irregular promontory of the underlying Arabian Plate contains different sedimentation depocentres. Small fining-upward submarine fan deposits (including pebbly channel deposits and coarsening-upward lobe sequences) are located at the centre of the irregular part of the plate (in the Tanır region) and overlie planktic foraminifera-bearing claystones. These submarine fan sediments pass outboard into distal interbedded turbidite claystones and siltstones in a downdip direction (S-SE). The boundary fault intersection of the promontory led to the development of a submarine slope environment with irregular sea-floor topography in the Fırnız area (4-5 km south-east of the Tanır region). The slump deposits, sandy debrites, and fine-grained thin-bedded turbidites filled this region. Structural alignments and seismicity associated with the plate margin were the main controlling factors on the geometry of the depocentre, sediment quantity, sediment input, sedimentary facies, local sea level changes, and post-sedimentary deformation in the Kahramanmaraş Foreland Basin.

  4. Experimental study on behavior of an open bottom floating platform in wave, wind and current

    SciTech Connect

    Qi Xinyuan

    1994-12-31

    The behavior of a moored open bottom floating platform has been investigated by a series of model tests at the wave basin of CSSRC (69 x 46 x 4m). The model tests were divided into two versions, i.e., version 1 for a conventional semi-submersible and version 2 for an open bottom floating platform. Comparison was made under the same mooring and environmental conditions including waves, steady wind and current. The results of model tests indicate that the open bottom floating platform is more stable and with less mooring loads than the conventional semi-submersible.

  5. Examination of the Feynman-Hibbs Approach in the Study of NeN-Coronene Clusters at Low Temperatures.

    PubMed

    Rodríguez-Cantano, Rocío; Pérez de Tudela, Ricardo; Bartolomei, Massimiliano; Hernández, Marta I; Campos-Martínez, José; González-Lezana, Tomás; Villarreal, Pablo; Hernández-Rojas, Javier; Bretón, José

    2016-07-14

    Feynman-Hibbs (FH) effective potentials constitute an appealing approach for investigations of many-body systems at thermal equilibrium since they allow us to easily include quantum corrections within standard classical simulations. In this work we apply the FH formulation to the study of NeN-coronene clusters (N = 1-4, 14) in the 2-14 K temperature range. Quadratic (FH2) and quartic (FH4) contributions to the effective potentials are built upon Ne-Ne and Ne-coronene analytical potentials. In particular, a new corrected expression for the FH4 effective potential is reported. FH2 and FH4 cluster energies and structures-obtained from energy optimization through a basin-hopping algorithm as well as classical Monte Carlo simulations-are reported and compared with reference path integral Monte Carlo calculations. For temperatures T > 4 K, both FH2 and FH4 potentials are able to correct the purely classical calculations in a consistent way. However, the FH approach fails at lower temperatures, especially the quartic correction. It is thus crucial to assess the range of applicability of this formulation and, in particular, to apply the FH4 potentials with great caution. A simple model of N isotropic harmonic oscillators allows us to propose a means of estimating the cutoff temperature for the validity of the method, which is found to increase with the number of atoms adsorbed on the coronene molecule. PMID:27058172

  6. The MiniBooNE Experiment

    SciTech Connect

    Ray, Heather L.

    2007-01-01

    Neutrino oscillations have been observed in three sectors : solar ({nu}{sub e} disappearance) [1], atmospheric ({nu}{sub {mu}} disappearance) [2], and accelerator ({bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e}) [3]. The probability for two-neutrino oscillation is a function of four variables : two are determined by the conditions of the experiment, and two are the quantities fit for when performing an oscillation search (sin{sup 2}(2{theta}) and {Delta}m{sup 2}). {Delta}m{sup 2} is the difference in squares of the mass states of the neutrinos ({Delta}m{sub 12}{sup 2} = m{sub 2}{sup 2}-m{sub 1}{sup 2}). If the observed oscillations only occur between neutrinos in the Standard Model a summation law of the {Delta}m{sup 2} is valid ({Delta}m{sub 13}{sup 2} = {Delta}m{sub 12}{sup 2} + {Delta}m{sub 23}{sup 2}). The observed oscillations do not follow this summation law. This implies one of the results is incorrect or there exists physics beyond the Standard Model. While the solar and atmospheric results have been confirmed by several different experiments, the accelerator based result, from the Los Alamos LSND experiment [3], has yet to be fully vetted. The MiniBooNE experiment [4], located at Fermi National Laboratory, is designed to fully explore the LSND result. MiniBooNE is in the final stages of performing a blind oscillation search ({nu}{sub {mu}} {yields} {nu}{sub e}) using neutrino data collected through November, 2005. A blind analysis is one in which you may analyze some of the information in all of the data, all of the information in some of the data, but not all of the information in all of the data. As MiniBooNE hasn't yet opened the box, this discussion will focus on the different components of MiniBooNE relevant for the oscillation analysis.

  7. Turbine blade platform seal

    DOEpatents

    Zagar, Thomas W.; Schiavo, Anthony L.

    2001-01-01

    A rotating blade group 90 for a turbo-machine having an improved device for sealing the gap 110 between the edges 112,114 of adjacent blade platforms 96,104. The gap 110 between adjacent blades 92,100 is sealed by a seal pin 20 its central portion 110 and by a seal plate 58,60 at each of the front 54 and rear 56 portions. The seal plates 58,60 are inserted into corresponding grooves 62,64 formed in the adjacent edges 112,114 of adjoining blades 92,100 and held in place by end plates 40,42. The end of the seal plates 58,60 may be chamfered 78,80 to improve the seal against the end plate 40,42. The seal pin 20 provides the required damping between the blades 92,100 and the seal plates 58,60 provide improved sealing effectiveness.

  8. Energy Tracking Software Platform

    SciTech Connect

    Ryan Davis; Nathan Bird; Rebecca Birx; Hal Knowles

    2011-04-04

    Acceleration has created an interactive energy tracking and visualization platform that supports decreasing electric, water, and gas usage. Homeowners have access to tools that allow them to gauge their use and track progress toward a smaller energy footprint. Real estate agents have access to consumption data, allowing for sharing a comparison with potential home buyers. Home builders have the opportunity to compare their neighborhood's energy efficiency with competitors. Home energy raters have a tool for gauging the progress of their clients after efficiency changes. And, social groups are able to help encourage members to reduce their energy bills and help their environment. EnergyIT.com is the business umbrella for all energy tracking solutions and is designed to provide information about our energy tracking software and promote sales. CompareAndConserve.com (Gainesville-Green.com) helps homeowners conserve energy through education and competition. ToolsForTenants.com helps renters factor energy usage into their housing decisions.

  9. Event sedimentation in low-latitude deep-water carbonate basins, Anegada passage, northeast Caribbean

    USGS Publications Warehouse

    Chaytor, Jason D.; ten Brink, Uri S.

    2015-01-01

    The Virgin Islands and Whiting basins in the Northeast Caribbean are deep, structurally controlled depocentres partially bound by shallow-water carbonate platforms. Closed basins such as these are thought to document earthquake and hurricane events through the accumulation of event layers such as debris flow and turbidity current deposits and the internal deformation of deposited material. Event layers in the Virgin Islands and Whiting basins are predominantly thin and discontinuous, containing varying amounts of reef- and slope-derived material. Three turbidites/sandy intervals in the upper 2 m of sediment in the eastern Virgin Islands Basin were deposited between ca. 2000 and 13 600 years ago, but do not extend across the basin. In the central and western Virgin Islands Basin, a structureless clay-rich interval is interpreted to be a unifite. Within the Whiting Basin, several discontinuous turbidites and other sand-rich intervals are primarily deposited in base of slope fans. The youngest of these turbidites is ca. 2600 years old. Sediment accumulation in these basins is low (−1) for basin adjacent to carbonate platform, possibly due to limited sediment input during highstand sea-level conditions, sediment trapping and/or cohesive basin walls. We find no evidence of recent sediment transport (turbidites or debris flows) or sediment deformation that can be attributed to the ca. M7.2 1867 Virgin Islands earthquake whose epicentre was located on the north wall of the Virgin Islands Basin or to recent hurricanes that have impacted the region. The lack of significant appreciable pebble or greater size carbonate material in any of the available cores suggests that submarine landslide and basin-wide blocky debris flows have not been a significant mechanism of basin margin modification in the last several thousand years. Thus, basins such as those described here may be poor recorders of past natural hazards, but may provide a long-term record of past oceanographic

  10. Fracture character and distribution in the Nenana basin, Alaska

    NASA Astrophysics Data System (ADS)

    Rizzo, A. J.; Hanks, C. L.

    2012-12-01

    The NE-SW trending Tertiary aged Nenana basin is located in the southeastern portion of central Alaska, north of Alaska Range. Forming adjacent to the Alaska Range, the tectonic setting resembles a foreland or strike-slip basin. This seismically active basin is estimated to be ~20,000 ft deep and is filled with non-marine sediments and coal-bearing sequences. Fracture character and distribution studies have been used to determine reservoir properties of the basin. By analyzing characteristics such as aperture, height, length and orientation, the origin of the fractures can be better understood. The seal integrity and extent of fracturing throughout the basin can aid in the understanding of the basin's history and its capability to be used for CO2 sequestration. The tectonic setting of central Alaska consists of two master right-lateral strike-slip faults that are proposed to create a shear zone with subsidiary left-lateral strike-slip faults. The southeastern margin of the basin is characterized by one of the subsidiary left-lateral faults proposed due to the master faults acting as major slip surfaces; the Minto fault, a predominately normal fault with a left-lateral strike-slip component. Available seismic data throughout the basin shows a strong extensional component with some possible flower structures. The orientation of the basin and its location in respect to both the Tintina-Kaltag and Denali right-lateral fault systems suggest that the basin is extending in the NE-SW direction. A fracture model has been proposed suggesting fractures related to the extensional component of the basin, but also tied to the fold and thrust belt located in the northern foothills of the Alaska Range. Data was obtained from a variety of locations in central Alaska in relation to the location of the basin. Fracture data was collected along the southeastern and southern portions of the basin in predominately metamorphic basement rocks and sedimentary sequences along the margin

  11. Platform evolution studies

    NASA Technical Reports Server (NTRS)

    Walton, Barbara A.

    1990-01-01

    The polar orbiting platform (POP), being developed by the Work Package 3 (WP3) Project at the Goddard Space Flight Center, will play a key role in the NASA Leadership Initiative, Mission to Planet Earth (MPE). It becomes, with the addition of payloads, an Earth observation satellite observatory. Mission to Planet Earth also has geostationary platforms (GEOP) as part of its global observational system. A study was begun in March 1988 to assess the applicability of the POP orbital replacement units (ORUs) for a geostationary Earth observing mission. Two test cases, representative of MPE payloads, were studied. Case A was used to emphasize the GEOP configuration and design; it used a Titan/Centaur to achieve orbit. Case B, considered to be much further in the future, included some assembly at the Space Station Freedom manned base and use of an orbital transfer vehicle to achieve orbit; requirements on the manned base to support such a mission were emphasized. The study found the POP systems more than adequate to meet GEOP requirements. Two types of changes were required for the POP ORUs: (1) modification to use only one surface for heat rejection; for the battery ORU, this meant 'opening up' the ORU to retain the radiator area with a corresponding decrease in depth; and (2) deletion of equipment not needed. The Case A configuration was shown to be within the planned capability of the Titan IV/Centaur. Assembly requirements were included for the Case B configuration, which is driven by the large microwave antennas of two of the payloads. The final review was April 19, 1989.

  12. Divergent/passive margin basins

    SciTech Connect

    Edwards, J.D. ); Santogrossi, P.A. )

    1989-01-01

    This book discusses the detailed geology of the four divergent margin basins and establishes a set of analog scenarios which can be used for future petroleum exploration. The divergent margin basins are the Campos basin of Brazil, the Gabon basin, the Niger delta, and the basins of the northwest shelf of Australia. These four petroleum basins present a wide range of stratigraphic sequences and structural styles that represent the diverse evolution of this large and important class of world petroleum basins.

  13. 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

  14. Structure of the Basin and Ridge System West of New Caledonia (Southwest Pacific): A Synthesis

    NASA Astrophysics Data System (ADS)

    Lafoy, Y.; Brodien, I.; Vially, R.; Exon, N. F.

    2005-03-01

    Complementary to previous work mainly based on seismic interpretation, our compilation of geophysical data (multibeam bathymetry, gravity, magnetic and seismic) acquired within the framework of the ZoNéCo (ongoing since 1993) and FAUST (1998 2001) programs enables us to improve the knowledge of the New Caledonia Basin, Fairway Basin and Fairway Ridge, located within the Southwest Pacific region. The structural synthesis map obtained from geophysical data interpretation allows definition of the deep structure, nature and formation of the Fairway and New Caledonia Basins. Development of the Fairway Basin took place during the Late Cretaceous (95 65 Ma) by continental stretching. This perched basin forms the western margin of the New Caledonia Basin. A newly identified major SW NE boundary fault zone separates northern NW SE trending segments of the two basins from southern N S trending segments. This crustal-scale fault lineament, that we interpret to be related to Cretaceous-early Cainozoic Tasman Sea spreading, separates the NW SE thinned-continental and N S oceanic segments of the New Caledonia Basin. We can thus propose the following pattern for the formation of the study area. The end of continental stretching within the Fairway and West Caledonia Basins ( 65 62 Ma) is interpreted as contemporaneous with the onset of emplacement of oceanic crust within the New Caledonia Basin’s central segment. Spreading occurred during the Paleocene (62 56 Ma), and isolated the Gondwanaland block to the west from the Norfolk block to the east. Finally, our geophysical synthesis enables us to extend the structural Fairway Basin down to the structural Taranaki Basin, with the structural New Caledonia Basin lying east of the Fairway Basin and ending further north than previously thought, within the Reinga Basin northwest of New Zealand.

  15. Structure of the basement beneath the Illizi Basin: insights from the reinterpretation of an aeromagnetic survey

    NASA Astrophysics Data System (ADS)

    Brahimi, Sonia; Bourmatte, Amar; Ghienne, Jean-François; Munschy, Marc

    2016-04-01

    The Illizi Basin is an intracontinental basin occupying the southeastern part of the Algerian Sahara platform at the northeastern junction of the Hoggar terranes with the East Saharan Metacraton. Aeromagnetic data covering an area of about 2000 km2, including the Illizi Basin, Tassilis and northeastern part of the Hoggar, are compiled to obtain a magnetic map with a special resolution of 600 m and interpreted in the light of that of the adjacent Hoggar Shield, the structural geology of which is well documented. Interpretation of the magnetic map uses potential field transformations like reduction to the pole, fractional vertical derivatives, analytic signal and tilt-depth. These transforms allow to identify beneath the cover of the Illizi Basin two main structural boundaries: 1) The N-S 'Raghane Mega-shear zone' (RSZ) at 8°30 E, manifested by a weak magnetic signal. It corresponds to the most important Panafrican suture, which separates the East Saharan Metacraton from the LATEA terrane assemblage (Metacraton of Central Hoggar). 2) A N-S mega-shear zone at 4°50 E (MSZ4) marked by a strong amplitude anomaly. It separates the Central (LATEA) from the Western Hoggar. Both mega-shear zones change their direction northward: to the NNE for the RSZ and to the NW for the MSZ4. To the west of the RSZ, inside the LATEA, another linear structure is identified by a weak amplitude magnetic lineation, which corresponds to the 7°30 E shear zone (SZ7) marking the western boundary of the Tazat-Assodé-Issalane terranes (TAI). Along SZ7is identified the strongest amplitude magnetic anomaly, which is in excess of 2000 nT and correlated spatially to the northern part of the Ounane pluton. Two other magnetic anomalies further north probably relate to similar bodies. Also a distinct area with strong amplitude magnetic anomalies is identified and extends 300 km toward the north below the sedimentary cover. It is associated to the northern extension of the TAI. In addition, N

  16. 18Ne Excited States Two-Proton Decay

    NASA Astrophysics Data System (ADS)

    de Napoli, M.; Rapisarda, E.; Raciti, G.; Cardella, G.; Amorini, F.; Giacoppo, F.; Sfienti, C.

    2008-04-01

    Two-proton radioactivity studies have been performed on excited states of 18Ne produced by 20Ne fragmentation at the FRS of the Laboratori Nazionali del Sud and excited via Coulomb excitation on a 209Pb target. The 18Ne levels decay has been studied by complete kinematical reconstruction. In spite of the low statistic, the energy and angular correlations of the emitted proton pairs indicate the presence of 2He emission toghether with the democratic decay.

  17. 13. WEST END, LOOKING NE, PHILADELPHIA ZOO LION SCULPTURE IN ...

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

    13. WEST END, LOOKING NE, PHILADELPHIA ZOO LION SCULPTURE IN FOREGROUND. - Connecting Railway, Schuylkill River Bridge, Spanning Schuylkill River, north of Girard Avenue Bridge, Philadelphia, Philadelphia County, PA

  18. Experimental melting of arc crustal pyroxenites and the origin of ultracalcic ne-normative melts in arc settings

    NASA Astrophysics Data System (ADS)

    Médard, E.; Schiano, P.; Schmidt, M. W.

    2003-04-01

    Primitive ultracalcic melts have been documented at mid-ocean-ridges, back-arc basins, oceanic islands and volcanic arcs. Ultracalcic nepheline-normative melts in island arcs occurs both as glass inclusions and lavas (Schiano et al., G3, 2000). The high CaO contents (up to 18 wt%), low SiO_2 contents (down to 43 wt%) and high CaO/Al_2O_3 ratios (up to 1.2) of these melts cannot be simply explained by lherzolite melting under anhydrous or hydrous conditions. Lherzolite melting involving CO_2-rich fluids produces high-CaO/Al_2O_3 liquids, however, low amounts of CO_2 (500 ppm, Sisson and Bronto, Nature, 1998) have been mesured in arc-related ultracalcic glass inclusions. Ne-normative ultracalcic melts could be generated by melting of carbonate-bearing lherzolites or by lherzolite melting in the garnet stability field (as suggested for nephelinites and melilitites). However, the ultracalcic ne-normative melts observed in arcs do not bear the caracteristic trace-element signatures of these processes. Is it possible to generate ultracalcic ne-normative liquids without CO_2? In order to add new constraints on this problem, multiple saturation experiments and direct melting experiments were performed on ne-normative compositions. Model ultracalcic melts are in equilibrium with olivine and clinopyroxene at crustal pressures (0.2 -- 0.7 GPa) and temperatures near 1250^oC. These results suggest that in arc settings, such melts can be derived at crustal levels from partial melting of ol-cpx rich rocks. Therefore, melting experiments were conducted on amphibole-bearing cpx-ol compositions at 0.50--1.0 GPa. Partial melts are ultracalcic above 1220--1250^oC, and in equilibrium with ol and cpx. Compared to lherzolite melting, cpx is more Ca-rich and a residual phase to higher melt fractions, so the maximum CaO content, reached at the cpx out, is higher. Mg# of melts increase with melt fraction, as do equilibrium Mg# of residual olivine (Fo82 to Fo89 at very high melt fraction

  19. Tracing tetraether lipids from source to sink in the Rhône River system (NW Mediterranean)

    NASA Astrophysics Data System (ADS)

    Kim, Jung-Hyun; Ludwig, Wolfgang; Buscail, Roselyne; Dorhout, Denise; Sinninghe Damsté, Jaap S.

    2015-04-01

    We investigated soils and river suspended particulate matter (SPM) collected in Rhône and its tributary basins as well as marine surface sediments collected in the Rhône prodelta (Gulf of Lions, NW Mediterranean). We traced the signal of branched glycerol dialkyl glycerol tetraethers (brGDGTs) from source to sink via rivers and identified the sources of brGDGTs in rivers and marine sediments. Core lipid (CL) fractions were investigated for soils as well as marine surface sediments. However, the concentration and distribution of brGDGTs of both CL and intact polar lipid (IPL) fractions were investigated for river SPM in order to distinguish more recently produced (IPL-derived) GDGTs from older (CL) GDGTs, since IPLs are less stable than CLs. Our results showed that soil pH explains most of the variance in the brGDGT distribution rather than mean annual air temperature (MAAT) in our soil dataset. The observed changes in the distribution of CL brGDGTs in the river SPM suggest that the provenance of CL brGDGTs brought by the river to the sea might be more restricted to certain areas in the lower Rhône River and its tributary basins. In the marine surface sediments, it appears that the input of riverine brGDGTs is the primary source of brGDGTs in the Rhône prodelta but the brGDGT composition may be slightly modified by in-situ production of brGDGTs in this system.

  20. A Platform to Stand On

    ERIC Educational Resources Information Center

    Texley, Juliana; Adelstein, David

    2006-01-01

    One of the most powerful technology tools available to science teachers is often the least used. A course management system (CMS) is a web-based application that provides an online distance learning platform for teachers and students. CMS platforms such as Blackboard, WebCT, Jenzabar, and Desire-2-Learn provide many opportunities for good science…

  1. First Survey For Submarine Hydrothermal Vents In NE Sulawesi, Indonesia

    NASA Astrophysics Data System (ADS)

    McConachy, T.; Binns, R.; Permana, H.

    2001-12-01

    The IASSHA-2001 cruise (Indonesia-Australia Survey for Submarine Hydrothermal Activity) was successfully conducted from June 1 to June 29 on board Baruna Jaya VIII. Preliminary results are reported of the first expedition to locate and study submarine hydrothermal activity in north east Sulawesi. Leg A focussed on Tomini Bay, a virtually unexplored Neogene sedimentary basin. Its objective was to test whether modern sediment-hosted hydrothermal activity occurred on the sea floor. The results of new bathymetric mapping, sediment coring and CTD/transmissometer hydrocasts negate the likely presence in central Tomini Bay of large-scale modern analogues of hydrothermal massive sulfide environments involving hydrothermal venting of basinal or magma-derived fluids into reduced sediments. It is possible that the "heat engine" required to drive circulation of basinal and hydrothermal fluids is today too weak. Surveys around Colo volcano indicate that it may be in its final stage of evolution. Leg B studied the arc and behind-arc sectors of the Sangihe volcanic island chain extending northwards from Quaternary volcanoes on the northeastern tip of Sulawesi's North Arm, near Manado. West of the main active chain and extending northwards from Manado there is a subparallel ridge surmounted by a number of high (>2000 m) seamounts of uncertain age. Fifteen relatively high-standing submarine edifices were crossed during this leg, of which nine were tested for hydrothermal activity by hydrocast and dredging. Eight sites were known from previous bathymetric surveys, and seven are new discoveries made by narrow-beam or multibeam echo sounding. Two submarine edifices at least 1000 m high were discovered in the strait immediately north of Awu volcano on Sangihe Island. One, with crest at 206 m, is surrounded by a circular platform 300m deep which we infer to be a foundered fringing reef to a formerly emergent island. The other, lacking such a platform, appears relatively young and may be

  2. Near real time water resources data for river basin management

    NASA Technical Reports Server (NTRS)

    Paulson, R. W. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. Twenty Data Collection Platforms (DCP) are being field installed on USGS water resources stations in the Delaware River Basin. DCP's have been successfully installed and are operating well on five stream gaging stations, three observation wells, and one water quality monitor in the basin. DCP's have been installed at nine additional water quality monitors, and work is progressing on interfacing the platforms to the monitors. ERTS-related water resources data from the platforms are being provided in near real time, by the Goddard Space Flight Center to the Pennsylvania district, Water Resources Division, U.S. Geological Survey. On a daily basis, the data are computer processed by the Survey and provided to the Delaware River Basin Commission. Each daily summary contains data that were relayed during 4 or 5 of the 15 orbits made by ERTS-1 during the previous day. Water resources parameters relays by the platforms include dissolved oxygen concentrations, temperature, pH, specific conductance, well level, and stream gage height, which is used to compute stream flow for the daily summary.

  3. Reproducible Experiment Platform

    NASA Astrophysics Data System (ADS)

    Likhomanenko, Tatiana; Rogozhnikov, Alex; Baranov, Alexander; Khairullin, Egor; Ustyuzhanin, Andrey

    2015-12-01

    Data analysis in fundamental sciences nowadays is an essential process that pushes frontiers of our knowledge and leads to new discoveries. At the same time we can see that complexity of those analyses increases fast due to a) enormous volumes of datasets being analyzed, b) variety of techniques and algorithms one have to check inside a single analysis, c) distributed nature of research teams that requires special communication media for knowledge and information exchange between individual researchers. There is a lot of resemblance between techniques and problems arising in the areas of industrial information retrieval and particle physics. To address those problems we propose Reproducible Experiment Platform (REP), a software infrastructure to support collaborative ecosystem for computational science. It is a Python based solution for research teams that allows running computational experiments on shared datasets, obtaining repeatable results, and consistent comparisons of the obtained results. We present some key features of REP based on case studies which include trigger optimization and physics analysis studies at the LHCb experiment.

  4. Prototype space fabrication platform

    NASA Astrophysics Data System (ADS)

    Bessel, James A.; Ceney, James M.; Crean, David M.; Ingham, Edward A.; Pabst, David J.

    1993-12-01

    Current plans for constructing large structures in space entail fabricating the primary components, such as truss segments, on the ground and assembling them in space. This process requires an exorbitant number of support missions, and methods to minimize the number must be considered. Whenever the space shuttle is launched, its external tank is jettisoned and destroyed prior to reaching orbit. This aerospace grade aluminum structure can be carried into orbit and utilized extrusively. The Prototype Space Fabrication Platform (SFP) fabricates aluminum materials, reduced from external tanks, into functional trusses. The trusses are strong and can be used as the primary components for future structures in space. The fabrication process produces a continuous truss allowing the end user to determine the length. The SFP can fabricate the same amount of truss from one external tank as four dedicated shuttle missions can deliver in the cargo bay. The SFP utilizes electrodynamic propulsion, via shielded coils, for maneuvering. The novel propulsion system facilitates a versatile payload transportation and delivery capability. The SFP can continuously track a target from all directions. The tracking system is ideal for docking since plume impingement is not a concern. With the assistance of remote manipulators, the SFP can deliver a payload in a wide variety of orientations. Under most conditions, the remote manipulator and maneuvering commands originate from ground workstations. Required manned presence is greatly reduced, and the time when the space shuttle is off station is effectively utilized. The logistical complications, currently inhibiting advancement in space, can be eliminated.

  5. La fin du jeûne?

    PubMed Central

    Naugler, Christopher; Sidhu, Davinder

    2014-01-01

    Résumé Objectif Présenter une mise à jour sur l’utilité clinique de ne pas être à jeun par rapport à l’être pour l’analyse des lipides dans le but d’améliorer l’observance par les patients, leur sécurité et l’évaluation clinique dans les tests du cholestérol. Qualité des données Les recommandations sont classées comme étant fondées sur des données probantes fortes, acceptables ou faibles (conflictuelles ou insuffisantes), selon les classifications adoptées par le Groupe d’étude canadien sur les soins de santé préventifs. Message principal Le dépistage de la dyslipidémie comme facteur de risque de coronaropathie et la prescription de médicaments hypolipidémiants sont des activités importantes en soins primaires. De récentes données probantes remettent en question la nécessité d’être à jeun pour la mesure des lipides. Dans des études sur la population, le cholestérol total, le cholestérol à lipoprotéines de haute densité et le cholestérol à lipoprotéines autres qu’à haute densité variaient tous d’en moyenne 2 % à jeun. Pour un dépistage de routine, la mesure du cholestérol sans être à jeun est maintenant une option de rechange raisonnable à l’analyse à jeun. Pour les patients diabétiques, l’exigence d’être à jeun peut représenter un important problème de sécurité en raison des possibilités d’hypoglycémie. Pour la surveillance des triglycérides et du cholestérol à lipoprotéines de basse densité chez les patients qui prennent des médicaments hypolipidémiants, le jeûne devient important. Conclusion Être à jeun pour la détermination routinière des niveaux lipidiques est largement inutile et il est improbable que le jeûne influence la stratification du risque clinique chez le patient, tandis que la mesure sans être à jeun pourrait améliorer l’observance par le patient et sa sécurité.

  6. Neogene Structural History of Biak and the Biak Basin, Eastern Indonesia

    NASA Astrophysics Data System (ADS)

    Gold, D.; Hall, R.; Burgess, P.

    2014-12-01

    The Biak Basin is within a frontier region, located between the islands of Biak to the north and Yapen to the south in the Indonesian province of West Papua. The Biak Basin is underlain by a Paleogene basement sequence that originated in an intra-oceanic island arc, formed on the leading edge of the oceanic Pacific-Caroline Plate. The basin has a structural history that can be divided into three stages: 1) a compressional stage, 2) a rifting stage and 3) a strike-slip stage. The compressional stage occurred during the Early Miocene. Collision of the arc with the northern edge of the Australian continental margin caused folding and thrusting of the basement sequence which was uplifted and subaerially exposed resulting in a widespread unconformity that can be traced west through the western Bird's Head as far as Halmahera. Following this collision the Biak Basin was filled largely by carbonates from the Early Miocene. During the Middle-Late Miocene the Biak Basin underwent a period of rapid subsidence resulting from a period of rifting. Extension occurred as convergence of the Pacific Plate with the Australian margin produced a regional stress field in which the maximum compressive stress was orientated NE-SW and maximum tensional stress NW-SE. This tensional stress produced NE-SW striking horsts and grabens with a Paleogene basement overlain by Lower Miocene carbonates. A final stage involving strike-slip faulting occurred during the Pliocene-Pleistocene with the initiation of major regional faults such as those of the Yapen Fault Zone and Biak Array which bound the southern and northeastern margins of the basin respectively. The strike-slip faulting accommodated continued convergence between the Pacific and Australian plates and uplifted Miocene carbonates as pop-up structures now observed on Biak.There are parallels to the Biak Basin in basins within the Basin and Range Province of the western United States, in particular the Walker Lake Basin, Nevada and other

  7. Proxy-agent management platform for OXC managed objects

    NASA Astrophysics Data System (ADS)

    Pahk, Soomyung; Joo, Seong-Soon; Nam, Hyun-Soon; Lee, Sang-Wha; Kim, Hae G.

    2001-10-01

    In this paper, we present a Proxy-Agent Management Platform, which supports the managed objects of the Optical Cross-Connects (OXC). OXC is a sophisticated WDM network element (NE) that makes the WDM networks reconfigurable. It consists of several sub-NEs, such as 3R modules, Mux/Demux modules, transponder modules, optical switch fabric modules, and operation administration and maintenance processing modules. The OXC network element manager requests and gathers the managed information, alarms, and events from those sub-NEs in the OXC network element, and updates the Management Information Base (MIB) of the OXC managed object existed in the local or remote OXC network element management system. We propose an OXC network element manager with proxy-agent functions which could configure, control, and manage the sub-NEs via an unified access interface on the Common Object Request Broker Architecture (CORBA). The proxy-agent in the OXC network element management system offers its own MIB information to SNMP and/or CMIP manager. The proposed platform achieves high code reusability, provides unified access interfaces between sub-NEs and proxy-agent via ORB, and offers authentication and authorization. The proposed platform is verified on simulated testbed, and shows that managed objects can be added or droped easily to develop an intelligent OXC system.

  8. Exploration applications of satellite imagery in mature basins - A summation

    SciTech Connect

    Berger, Z. )

    1991-08-01

    A series of examples supported by surface and subsurface controls illustrates procedures used to integrate satellite imagery interpretation into a conventional exploration program, and the potential contribution of such an approach to the recognition of new hydrocarbon plays in mature basins. Integrated analysis of satellite imagery data consists of four major steps. The first step focuses on the recognition of style, trend, and timing of deformation of exposed structures located at the basin interior or around its margins. This information is obtained through an integrated analysis of satellite imagery data, stereo aerial photography, surface geological mapping, and field observations. The second step consists of integrating the satellite imagery with gravity and magnetic data to recognize obscured and/or buried structures. The third step involves the analysis of available seismic data which is specifically processes to enhance subtle basement topography in order to determine influences on reservoir quality. In the fourth step, subsurface structure, isopach, show, and pool maps derived from available well information are integrated into the structural interpretation. These four analytical steps are demonstrated with examples form the Powder River basin, Western Canada basin, Paris basin, and Central basin platform of west Texas. In all of these highly mature basins, it is easy to demonstrate that (1) hydrocarbon migration and accumulation was largely controlled by subtle basement structures, and (2) these structures can be detected through the integrated analysis of satellite imagery.

  9. Jurassic midbaisn platform, central and eastern High Atlas Morocco

    SciTech Connect

    Warme, J.E. )

    1988-08-01

    The central and eastern High Atlas ranges of southern Morocco coincide with a Mesozoic 100 {times} 500-km east-west rift. Upper Triassic to lower Liassic continental red beds, evaporites, and basalts, unconformably overlying Paleozoic metasediments, comprise basin-wide initial synrift deposition. These are abruptly overlain by up to 40 m of Hettangian or lower Sinemurian block, laminated, unfossiliferous limestones deposited in a euxinic hypersaline and/or stratified sea. Continued syndepositional transtension differentiated the embryonic seaway into a mosaic of fault blocks comprising an axial midbasin platform symmetrically flanked to the north and south by turbidite troughs, basin-margin shelves, and shores. The midbasin platform serves as an exposed model for structurally analogous platforms in oil-producing basins such as west Texas. It has a unique Liassic upward-shallowing limestone sequence approximately 450 m thick, now widely exposed by en echelon ridges upthrusted over a minimal axial area of 20 {times} 150 km. The basal laminated euxinic facies (potential source rock) becomes interbedded upward with bioturbated limestones, indicating cyclic presence of normal marine bottom waters. Overlying strata are completely bioturbated nodular limestones with rare diminutive shelled benthos and chert nodules resembling sponge morphologies. The upper 250 m of the sequence exhibit increasing bed thickness, abundance and diversity of shelly benthos, and frequency and size of sponge-algal mud mounds (potential reservoirs), indicating overall shallowing but generally below wave base. The sequence culminates in giant sponge-algal buildups with up to 200 m of relief, abruptly capped by a starved surface rich with ammonites related to a late Liassic (Toarcian) eustatic sea level rise.

  10. Factors affecting fish assemblages associated with gas platforms in the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Consoli, Pierpaolo; Romeo, Teresa; Ferraro, Maria; Sarà, Gianluca; Andaloro, Franco

    2013-03-01

    Understanding the role played by offshore platforms in marine ecosystems is acquiring increasing importance worldwide. In this work, underwater visual census techniques were applied to describe spatial and temporal patterns of fish assemblages associated with extractive platforms. Data were collected during three seasons according to the following spatial factors: Location (Adriatic and Ionian Seas), Depth (0-6 m and 12-18 m) and Distance from the platform (external and internal). Both univariate and multivariate analyses showed highly significant differences for each factor assessed in this study, as well as for the interaction among said factors. Results indicated that artificial structures in both the Adriatic and Ionian Seas act as artificial reefs attracting reef-dwelling or partially reef-dwelling species, which are not present far from the platforms in open waters. Results also showed significant differences between Ionian and Adriatic fish assemblages, with a higher mean density of fish and a greater mean number of species in the latter basin. Boops boops, Chromis chromis and several species belonging to the Blennidae family most contributed to these differences. This is likely due to the eutrophication that involves the coast of the northern and central Adriatic, allowing a high production of fish, especially planctivorous. Thanks to the eutrophication, platforms located in this basin are characterized by a greater abundance of fouling organisms which offer a perfect habitat for cryptobenthic species, such as Blennids. Moreover, Thalassoma pavo and Scorpaena maderensis, thermophilic species, were more abundant in the Ionian platforms than in the Adriatic ones thus contributing to the dissimilarities between these two basins. Present results could bear strong implications for the environmental management of drilling and production activities in different basins. Assessing biodiversity in these highly complex contexts is a challenge for the near future, and

  11. He-Ne laser treatment on menorrhagia

    NASA Astrophysics Data System (ADS)

    Ding, Ai-Hua

    1993-03-01

    By using He-Ne laser treatment, 84.7 - 91.1% of patients with menorrhagia, a common symptom of multiple gynecological diseases, are treated effectively. After laser irradiation, the amount of vaginal bleeding was reduced 47.1% on average. It has been proven that low-energy laser is an effective non-traumatic, painless, and easily acceptable new physical method in patients with menorrhagia. To study the mechanisms of efficiency, the quantitative determination of PGE2, PGF2(alpha ), 6-Keto-PGF1(alpha ), TXB2 in endometrium and blood flow before and after treatment were carried out. The results suggest that the effectiveness may be due to the recovery regulation of local uterine PGS level.

  12. MiniBooNE Oscillation Results 2011

    SciTech Connect

    Djurcic, Zelimir

    2012-01-01

    The MiniBooNE neutrino oscillation search experiment at Fermilab has recently updated results from a search for {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e} oscillations, using a data sample corresponding to 8.58 x 10{sup 20} protons on target in anti-neutrino mode. This high statistics result represent an increase in statistics of 52% compared to result published in 2010. An excess of 57.7 {+-} 28.5 events is observed in the energy range 200 MeV < E{sub {nu}} < 3000 MeV. The data favor LSND-like {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e} oscillations over a background only hypothesis at 91.1% confidence level in the energy range 475 < E{sub {nu}} < 3000 MeV.

  13. Electron impact collision strengths in Ne VII

    SciTech Connect

    Di, L.; Shi, J.R.; Zhao, G.

    2012-07-15

    The lines of Ne VII have been observed in many astronomical objects, and some transitions from high energy levels were observed both in Seyfert galaxies and stellar coronae. Thus, the atomic data for these transitions are important for modeling. Using the code FAC we calculated the collision strengths based on the distorted-wave method with large configuration interactions included. The Maxwellian averaged effective collision strengths covering the typical temperature range of astronomical and laboratory hot plasmas are presented. We extend the calculation of the energy levels to n=4 and 5. The energy levels, wavelengths, spontaneous transition rates, weighted oscillator strengths, and effective collision strengths were reported. Compared with the results from experiment or previous theoretical calculations a general agreement is found. It is found that the resonance effects are important in calculating the effective collision strengths.

  14. He-Ne laser extravascular irradiation therapy

    NASA Astrophysics Data System (ADS)

    Chen, Rong; Chen, Huifang; Xie, Shusen; Chen, Yanjiao; Zhang, Yanrong

    2000-10-01

    Based on the study of tissue optics related with the laser irradiation blood therapy, a new treatment method, extravascular low-level laser irradiation therapy (ELLLI) is developed. The veins of 30 patients with cerebrovascular disease combined with diabetes, asthma were treated by He-Ne laser (632.8nm, 25mW) which was delivered by an optics fiber. The fiber was outside the patient's skin and the laser irradiated on the blood vessel perpendicularly. The therapy time was 60 minutes each time and about 7-10 times a course of the treatment. The values of blood sugar, blood- fat and hemorrheology were measured as the effective indexes. After the treatment the effective indexes and the symptoms of the patients were all improved. With the advantages of simplicity and safety (no medical infection), laser extravascular irradiation therapy is likely to be a new medical method for heart brain and other diseases.

  15. Evidence for oceanic crust in the Herodotus Basin

    NASA Astrophysics Data System (ADS)

    Granot, Roi

    2016-04-01

    Some of the fundamental tectonic problems of the Eastern Mediterranean remain unresolved due to the extremely thick sedimentary cover (10 to 15 km) and the lack of accurate magnetic anomaly data. I have collected 7,000 km of marine magnetic profiles (2012-2014) across the Herodotus and Levant Basins, Eastern Mediterranean, to study the nature and age of the underlying igneous crust. The towed magnetometer array consisted of two Overhauser sensors recording the total magnetic anomaly field in a longitudinal gradiometer mode, and a fully oriented vector magnetometer. The total field data from the Herodotus Basin reveal a newly detected short sequence of long-wavelength NE-SW lineated anomalies that straddle the entire basin suggesting a deep two-dimensional magnetic source layer. The three components of the magnetic vector data indicate that an abrupt transition from a 2D to 3D magnetic structure occurs east of the Herodotus Basin, along where a prominent NE-SW gravity feature is found. Altogether, these new findings confirm that the Herodotus Basin preserves remnants of oceanic crust that formed along the Neotethyan mid-ocean ridge system. The continuous northward and counterclockwise motion of the African Plate during the Paleozoic and Mesozoic allow predicting the evolution of remanent magnetization directions, which in-turn dictate that shape of the anomalies. The shape of the Herodotus anomalies best fit Late Carboniferous to Early Permian (300±20 Myr old) magnetization directions. Finally, I will discuss the implications of these results on the tectonic architecture of the region as well as on various geodynamic processes.

  16. Stratigraphy of the Sarkisla area, Sivas basin, eastern central Anatolia

    SciTech Connect

    Bilgic, T.; Sumengen, M.; Terlemez, I.; Unay, E.; Gurbuz, M.; Erkan, E.

    1988-08-01

    The stratigraphy of the Sarkisla area, southeastern Central Anatolian Massif, is characterized by a succession of rock units ranging from late Paleocene to Pliocene in age. The Caldag group mostly consists of deep-water units and forms the base of the Tertiary rocks. However, its relation to the basement rocks is not observed in the area. This group is represented by late Paleocene-Lutetian-age turbiditic pyroclastics and limestones, andesitic lavas and pyroclastics topped with reefal limestones, and turbiditic limestones and pyroclastics alternating with limestone blocks. During Lutetian to early Priabonian time, shallow marine clastics were deposited along the southern margin of the basin, while continental clastics and platform limestones accumulated along the northern margin. Late Priabonian to early Oligocene time is represented by gypsiferous deposits followed by late Oligocene-age fluvial clastics. The gypsiferous deposits conformably overlie the shallow marine formations but rest on the Caldag group unconformably. During early to middle Miocene time, alternating lacustrine limestones, gypsum, and basalts formed on the fluvial clastics; to the north, basalts formed on the platform limestones. The uppermost sequence of the basin, composed of Tortonian-early Pliocene-age fluvial clastics, lacustrine limestones, and fan deposits, unconformably overlies the older formations. The stratigraphy of the study area is similar to the Ulukisla basin, southwestern Central Anatolian Massif. Therefore, this basin can be considered to be the prolongation of the Ulukisla basin offset by the Ecemis fault.

  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. Paleoenvironmental dynamics in the southern Pannonian Basin during initial Middle Miocene marine flooding

    NASA Astrophysics Data System (ADS)

    Pezelj, Đurđica; Mandic, Oleg; Ćorić, Stjepan

    2013-02-01

    Paleoenvironmental analysis based on foraminiferal distribution has been carried out on 44 sediment bulk samples from the locality Bogutovo selo near Ugljevik (NE Bosnia and Herzegovina). During the Middle Miocene the region was positioned on the southern margin of the Pannonian Basin and the Central Paratethys Sea. The studied section comprises ≈ 70-m-thick sedimentary succession dominated by marine marls and intercalated in its middle part by a single 14-m-thick limestone package. Marine succession superposes by angle discordance Oligocene coal-bearing deposits. The marker species allow correlation of the lower part of the section with the Early Badenian Upper Lagenidae Zone, whereas for the middle and upper part, the Middle Badenian Spirorutilus Zone was inferred. Integrating data from calcareous nannoplankton, the stratigraphic range has been limited to the time interval of 14.36-13.65 Ma (late NN5, late Langhian). The statistical agglomerative techniques applied to benthic foraminiferal distribution suggest the presence of six assemblages showing gradual transition from one to another. Their paleoenvironmental significance points to initial upward deepening of the depositional environment as a result of the Badenian transgression. This trend is interrupted by major sealevel- fall and switch to carbonate platform conditions in the middle part of the section. Subsequent sea-level-rise and increased primary production resulted in progressive reduction of oxygen content at the sea bottom in the upper part of the section. The stratigraphic position in the topmost NN5 Zone implies the correlation of the major sea-level-fall with the glacio-eustatic isotopic event Mi-3b astronomically dated to 13.82 Ma and coinciding with the base of the Serravallian.

  19. Shallow properties of faults in carbonate rocks - The Jandaíra Formation, Potiguar Basin, Brazil

    NASA Astrophysics Data System (ADS)

    Bezerra, F. H.; Bertotti, G.; Rabelo, J.; Silva, A. T.; Carneiro, M. A.; Cazarin, C. L.; Silva, C. C.; Vieira, M. M.; Bisdom, K.; Moraes, A.

    2014-12-01

    We studied the development of shallow faults in the Jandaíra Formation, a Turonian-Campanian carbonate platform in the Potiguar Basin, northeastern Brazil. Our main goal was to characterize fault geometry and properties such as porosity and permeability, and associate these results with fluid flow in shallow conditions. We used an integrated multidisciplinary approach, which combined Quickbird satellite and an unmanned aerial vehicle (UAV, drone) imagery, structural and sedimentary-facies mapping, and petrographic and petrophysical analyses. The Jandaíra Formation presents a variety of carbonate facies, which include mudstones to bioclastic, peloidal, intraclastic, and oolitic grainstones. We modeled our remote sensing and structural data using a finite element analysis system for 2D deformation modeling. We applied the magnitudes and directions of the present-day stress field to simulate depths as deep as 500 m. These stress data were derived from borehole breakout data and drilling-induced tensile fractures observed in resistivity image logs. Our results indicate the occurrence of dilation processes along three sets of joints that were reactivated as faults in the upper crust: N-S, NE-, and E-W-striking faults. These faults provided preferential leaching pathways to fresh water percolation, contributing to localized dissolution and increased secondary porosity and permeability. The results also indicate that the tectonic stresses are concentrated in preferred structural zones such as fault intersection and termination, which are sites of increased fracturing and dissolution. Dissolution by fluids increased permeability in carbonate rocks from primary values of 0.0-0.94 mD to as much as 1370.11 mD. This process is mostly Cenozoic.

  20. RELEASE OF NE01643 HARD RED WINTER WHEAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NE01643 is a hard red winter wheat (Triticum aestivum L.) cultivar developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS and released in 2007 by the developing institutions and the South Dakota Agricultural Experiment Station. NE01643 will be marketed under the na...

  1. 75 FR 12166 - Class E Airspace; Beatrice, NE

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-15

    .... 106(g); 40103, 40113, 40120; E.O. 10854, 24 FR 9565, 3 CFR, 1959-1963 Comp., p. 389. Sec. 71.1 2. The... Federal Aviation Administration 14 CFR Part 71 Class E Airspace; Beatrice, NE AGENCY: Federal Aviation... Class E airspace at Beatrice, NE. Decommissioning of the Shaw non-directional beacon (NDB) at...

  2. Creating new growth platforms.

    PubMed

    Laurie, Donald L; Doz, Yves L; Sheer, Claude P

    2006-05-01

    Sooner or later, most companies can't attain the growth rates expected by their boards and CEOs and demanded by investors. To some extent, such businesses are victims of their own successes. Many were able to sustain high growth rates for a long time because they were in high-growth industries. But once those industries slowed down, the businesses could no longer deliver the performance that investors had come to take for granted. Often, companies have resorted to acquisition, though this strategy has a discouraging track record. Over time, 65% of acquisitions destroy more value than they create. So where does real growth come from? For the past 12 years, the authors have been researching and advising companies on this issue. With the support of researchers at Harvard Business School and Insead, they instituted a project titled "The CEO Agenda and Growth". They identified and approached 24 companies that had achieved significant organic growth and interviewed their CEOs, chief strategists, heads of R&D, CFOs, and top-line managers. They asked, "Where does your growth come from?" and found a consistent pattern in the answers. All the businesses grew by creating new growth platforms (NGPs) on which they could build families of products and services and extend their capabilities into multiple new domains. Identifying NGP opportunities calls for executives to challenge conventional wisdom. In all the companies studied, top management believed that NGP innovation differed significantly from traditional product or service innovation. They had independent, senior-level units with a standing responsibility to create NGPs, and their CEOs spent as much as 50% of their time working with these units. The payoff has been spectacular and lasting. For example, from 1985 to 2004, the medical devices company Medtronic grew revenues at 18% per year, earnings at 20%, and market capitalization at 30%. PMID:16649700

  3. Preliminar Performance Assessment of NeQuick2-Plas Model

    NASA Astrophysics Data System (ADS)

    Migoya Orue, Yenca; Gulyaeva, Tamara; Nava, Bruno; Radicella, Sandro M.

    NeQuick is a semi-empirical model that describes spatial and temporal variations of the ionospheric electron density at global scale. It was jointly developed by the Aeronomy and Radiopropagation Laboratory of the Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy and the Institute for Geophysics, Astrophysics and Meteorology of the University of Graz, Austria. The model is able to calculate the electron concentration at any given location in the ionosphere as well as the total electron content (TEC) along any ground-to-satellite ray-path. One of the recent major changes introduced in the NeQuick2 model is the integration of the plasmasphere formulation of IRI-Plas that gave origin to the NeQuick-Plas. The plasmasphere extension of IRI, IRI-Plas, is an empirical model derived from many years of measurements designed to represent typical ionospheric conditions as a function of geomagnetic and solar activity. For the smooth fitting of the NeQuick and plasmasphere models, the half-peak density point, h0.5p is searched iteratively from NeQuick topside electron density profile. The present study uses median values of IGS combined global vertical TEC maps as reference to be compared with NeQuick 2 and NeQuick-Plas models. Representative months of years of high, moderate and low solar activity have been utilized. The preliminary results indicate an improvement of the NeQuick 2 -Plas with respect to NeQuick 2 especially during periods of high and moderate solar activity as indicated by the average and standard deviation of the TEC error distributions (e.g. IGS-NeQ2 mean is -9.73, standard deviation is 5.6 while IGS-NePlas mean is 2.87, with a standard deviation of 4.8 for October 2000; IGS-NeQ2 mean is -5.28, standard deviation is 0.37 while IGS-NeQ-Plas mean is 1.25, standard deviation of 0.49 for Jul 2003). During low solar activity (year 2008), instead, there is a slight tendency of NeQuick-Plas to overestimate TEC values and so increase the

  4. Diagenesis and fracturing of a large-scale, syntectonic carbonate platform

    NASA Astrophysics Data System (ADS)

    Arosi, Hamed A.; Wilson, Moyra E. J.

    2015-08-01

    The influence of coeval tectonics on carbonate platform development is widely documented, yet the diagenesis of such syntectonic platforms is barely evaluated. An outcrop, petrographic and geochemical study details here for the first time the diagenesis of the Tonasa Limestone Formation developed in an extensional regime in central Indonesia. This equatorial carbonate system was affected by block faulting, tilt-block rotation, differential uplift and subsidence throughout its Eocene to Early Miocene history (Wilson, 1999; Wilson et al., 2000). The Tonasa carbonate platform is dominated by alteration in shallow to deeper burial depths by fluids with predominantly marine precursor origins. Mechanical and chemical compaction features are common, as are a range of mainly burial-related granular mosaic, blocky and equant calcite cements. Earlier marine cements and meteoric influences are rare, being highly localised to block faulted highs and/or bathymetrically upstanding platform margin areas. Early marine micritisation of allochems was common on the platform top. Tectonic uplift together with a major oceanic throughflow current are thought to be key influences on localised karstification, meteoric diagenesis and marine cementation. The distribution and orientation of faults, fractures and calcite veins together with evidence for their relative timing are the strongest manifestation of tectonism coeval with diagenesis. There is concordance in the orientation and timing of structures affecting the Tonasa Platform with those basin-wide, with the potential for reactivation of pre-existing basement fabrics. Tectonic subsidence, including fault-associated differential subsidence, controlled the degree of burial diagenesis impacting different areas of the platform. A predominance of burial diagenetic features and dearth of earlier marine or meteoric cementation is seen in other Tertiary equatorial platforms and is partly attributed to: (1) predominance of non

  5. Addendum to the MiniBooNE Run Plab. MinneBooNE Physics in 2006

    SciTech Connect

    Aguilar-Arevalo, A. A.

    2004-11-02

    The primary physics goal of Mini BooNE is to confirm or rule out the LSND vμ→ve oscilliation observation with high significance. In the 2003 Run Plan document presented to the PAC, we outlined the need for 1 X 1021 protons on target (POT) to achieve this goal. In this document, we present an addendum to our run plan for fiscal year 2006 (FY2006).

  6. Sequence stratigraphy and depositional facies of the Silurian-Devonian interval of the northern Permian basin

    SciTech Connect

    Canter, K.L.; Geesaman, R.C. ); Wheeler, D. )

    1992-04-01

    The Silurian and Devonian intervals of the northern Central Basin platform area of west Texas and southeastern New Mexico include the Fusselman, Wristen, and Thirtyone formations and the Woodford Shale. The carbonate-rich Fusselman, Wristen, and Thirtyone formations record a transition from ramp to platform deposition. Oolite grainstones of the lower Fusselman Formation were deposited in a ramp setting during an Upper Ordovician/Lower Silurian transgression. The overlying crinoid packstones and grainstones represent shoals that developed along a break in slope separating the evolving platform from a southward-dipping starved basin. By the close of Fusselman deposition, the platform was well developed, with shallow peridtidal mudstones and wackestones, and high-energy grainstones deposited as near-parallel facies tracts over the platform area. The platform system became fully developed during the deposition of the Wristen Formation. Porous dolomitic peridtidal and platform margin facies grade downdip into nonporous, limy and argillaceous open-shelf facies. Platform facies are typified by numerous shallowing-upward parasequences that terminated at subaerial exposure surfaces. The rocks of the Lower Devonian Thirtyone Formation were deposited as a wedge that onlaps the exposed Silurian platform margin. This formation contains a porous, chert-rich, lowstand deposit; a transgressive disconformity; and variably porous, grain-rich highstand deposits representing an overall sea level rise. A major unconformity marks the contact between the karsted upper surface of the Thirtyone Formation and the overlying organic-rich, anoxic Woodford Shale.

  7. Comparative effects of tectonism on Silurian carbonate platform evolution

    SciTech Connect

    Soja, C.M. . Geology Dept.)

    1992-01-01

    Detailed comparisons of Silurian carbonates that formed under similar subtropical-tropical conditions in an island arc (Alexander terrane, Alaska), an orogenic belt (Oslo region, Norway), and on a stale craton (Gotland, Sweden) are used to evaluate tectonic controls on carbonate platform sedimentation. Silurian carbonates from Alaska record the evolution of a submarine platform in an island arc affected by late Silurian orogenesis. Silurian limestones that formed on the Baltoscandinavian epicontinental platform experienced Caledonian orogenesis in the Oslo region but accumulated on Gotland several 100 km east of the Caledonide front under quiescent tectonic conditions. This study shows that previous models for carbonate platform development do not predict the disproportionately thick carbonate sequences and characteristics of rocks preserved in the Alaskan island arc. High rates of subsidence and accumulation, steep submarine slopes, tectonic instability, and biogeographic isolation resulted in extraordinarily thick platform and periplatform carbonates, sequential evolution of fringing and barrier reefs, and patterns of faunal turnover that differentiate Silurian arc deposits from coeval carbonates that formed on the craton and in the orogenic belt. On the craton and in the orogenic belt, marine organisms were relatively unaffected by tectonic disturbances, but in the island arc marine biotas experienced regional extinction and faunal turnover. Similarities in the stages in carbonate platform development in the Oslo region and Alaska reflect comparable events involving compression, foreland basin evolution, and subsequent rejuvenation of carbonate depositional sites. Widespread destruction of carbonate environments correlated with orogenic activity and global marine regression eventually produced similar subaerial conditions in the Alexander terrane and across Baltoscandinavia by the late Silurian.

  8. Space platform advanced technology study

    NASA Technical Reports Server (NTRS)

    Burns, G.

    1981-01-01

    Current and past space platform and power module studies were utilized to point the way to areas of development for mechanical devices that will be required for the ultimate implementation of a platform erected and serviced by the Shuttle/Orbiter. The study was performed in accordance with a study plan which included: a review of space platform technology; orbiter berthing system requirements; berthing latch interface requirements, design, and model fabrication; berthing umbilical interface requirements and design; adaptive end effector design and model fabrication; and adaptive end effector requirements.

  9. The Oquirrh basin revisited

    SciTech Connect

    Erskine, M.C.

    1997-04-01

    The upper Paleozoic succession in the Oquirrh basin in unusually thick, up to 9300 m, and consists mainly of a Pennsylvanian-middle Permian miogeocline of northwestern Utah. Previous workers have suggested a tectonic origin for the Oquirrh basin that is incompatible with the basin location in both time and space. There is no evidence for Pennsylvanian and Lower Permian tectonism in the middle of the miogeocline. Thermal evidence from the Mississippian Mission Canyon shale does no support the implied deep burial of the crustal sag models of basin formation. Stratigraphic and facies evidence indicates a growth fault origin for the basin. Regional isopach maps and facies maps are powerful tools in interpreting depositional environments and in reconstructing fold-and-thrust belts. However, the location of measured sections relative to the location of the growth fault basin. The Charleston-Nebo thrust may have essentially reversed the movement on a growth fault. Thick Oquirrh basin sedimentary rocks may not be required to balance structural sections across this thrust fault. A thin-skinned, extensional growth fault origin for the Oquirrh basin implies that the Cordilleran miogeocline did not participate in the Pennsylvanian north-vergent uplifts of the Ancestral Rocky Mountains.

  10. Photoionization and Recombination of ne IV and Excitation of NeV in Nebular Plasmas

    NASA Astrophysics Data System (ADS)

    Nahar, Sultana N.; Palay, Ethan; Pradhan, Anil K.

    2013-06-01

    %TEXT OF YOUR ABSTRACT The inverse processes of photoionization and electron-ion recombination are dominant in photoionized astrophysical plasmas. They determine the ionization fractions in photoionization equilibrium, physical conditions, and chemical abundances. We employ the unified theory of electron-ion recombination to study photoionization of Ne IV in photoionized nebulae. That leads to the production of Ne V and spectral emission of forbidden optical and mid-infrared [Ne V] lines via collisional excitation. These lines are prominent in the observations made by infrared space observatories SPITZER, SOFIA, and HERSCHEL. The unified method for electronic recombination provides self-consistent data for photoionization and recombination that is necessary to eliminate uncertainties in the determination of ionization fractions. To wit: Precise abundance of neon in the Sun is unknown owing to lack of accurate atomic data. A 20-level wave function expansion is used for the calculations of photoionization, recombination, and collisional excitation employing the relativistic Breit-Pauli R-matrix method in the close coupling approximation. We find and delineate extensive resonance structures at low energies that considerably enhance the effective cross sections and rates in astrophysical sources. Acknowledgement: Partially supported by DOE and NSF. Computational work was carried out at the Ohio Supercomputer Center

  11. Devonian Great Barrier Reef of Canning basin, Western Australia

    SciTech Connect

    Playford, P.E.

    1980-06-01

    A well-preserved Middle to Upper Devonian barrier-reef belt is exhumed as a series of limestone ranges for 350 km along the northern margin of the Canning basin. The reefs are of international importance for reef research because of the excellence of exposures and the lack of extensive dolomitization or structural deformation. They are also known in the subsurface, where they are regarded as prime objectives for oil exploration. The platforms were built by stromatoporoids, algae, and corals in the Givetian and Frasnian, and by algae in the Famennian. The platform and basin deposits were laid down nearly horizontally, whereas the marginal-slope deposits accumulated on steep depositional slopes. Geopetal fabrics, which quantify depositional and tectonic-compactional dip components, provide paleobathymetric data concerning the reef complexes and their fossil biotas. The reef limestones were subject to strong submarine cementation, resulting in very early porosity destruction, whereas the back-reef deposits of the platform interiors remained largely uncemented and retained most of their primary porosity. Stylolitization and associated compaction were greatest in limestones whose primary porosity was not destroyed by early submarine cementation. Consequently the platform interiors have compacted more than the margins, resulting in the typical concave shape of many platforms. Cementation concomitant with stylolitization destroyed most of the porosity that remained in the limestones after early submarine diagenesis. The most porous rocks now are dolomites having secondary moldic porosity. 27 figures.

  12. Burial, Uplift and Exhumation History of the Atlantic Margin of NE Brazil

    NASA Astrophysics Data System (ADS)

    Japsen, Peter; Bonow, Johan M.; Green, Paul F.; Cobbold, Peter R.; Chiossi, Dario; Lilletveit, Ragnhild

    2010-05-01

    We have undertaken a regional study of landscape development and thermo-tectonic evo-lution of NE Brazil. Our results reveal a long history of post-Devonian burial and exhuma-tion across NE Brazil. Uplift movements just prior to and during Early Cretaceous rifting led to further regional denudation, to filling of rift basins and finally to formation of the Atlantic margin. The rifted margin was buried by a km-thick post-rift section, but exhumation began in the Late Cretaceous as a result of plate-scale forces. The Cretaceous cover probably extended over much of NE Brazil where it is still preserved over extensive areas. The Late Cretaceous exhumation event was followed by events in the Paleogene and Neogene. The results of these events of uplift and exhumation are two regional peneplains that form steps in the landscape. The plateaux in the interior highlands are defined by the Higher Surface at c. 1 km above sea level. This surface formed by fluvial erosion after the Late Cretaceous event - and most likely after the Paleogene event - and thus formed as a Paleogene pene-plain near sea level. This surface was reburied prior to the Neogene event, in the interior by continental deposits and along the Atlantic margin by marine and coastal deposits. Neo-gene uplift led to reexposure of the Palaeogene peneplain and to formation of the Lower Surface by incision along rivers below the uplifted Higher Surface that characterise the pre-sent landscape. Our results show that the elevated landscapes along the Brazilian margin formed during the Neogene, c. 100 Myr after break-up. Studies in West Greenland have demonstrated that similar landscapes formed during the late Neogene, c. 50 Myr after break-up. Many passive continental margins around the world are characterised by such elevated plateaus and it thus seems possible, even likely, that they may also post-date rifting and continental separation by many Myr.

  13. K Basin safety analysis

    SciTech Connect

    Porten, D.R.; Crowe, R.D.

    1994-12-16

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall.

  14. The beginning of the Buntsandstein cycle (Early-Middle Triassic) in the Catalan Ranges, NE Spain: Sedimentary and palaeogeographic implications

    NASA Astrophysics Data System (ADS)

    Galán-Abellán, Belén; López-Gómez, José; Barrenechea, José F.; Marzo, Mariano; De la Horra, Raúl; Arche, Alfredo

    2013-10-01

    The Early-Middle Triassic siliciclastic deposits of the Catalan Ranges, NE Spain, are dominated by aeolian sediments indicating a predominance of arid climate during this time span, in sharp contrast with the coeval fluvial sediments found in the Castilian Branch of the Iberian Ranges, 300 km to the SW. The NE-SW-oriented Catalan Basin evolved during the Middle-Late Permian as the result of widespread extension in the Iberian plate. This rift basin was bounded by the Pyrenees, Ebro and Montalbán-Oropesa highs. The Permian-Early Triassic-age sediments of the Catalan Basin were deposited in three isolated subbasins (Montseny, Garraf, Prades), separated by intrabasinal highs, but linked by transversal NW-SE oriented faults. The three subbasins show evidence of diachronic evolution with different subsidence rates and differences in their sedimentary records. The Buntsandstein sedimentary cycle started in the late Early Triassic (Smithian-Spathian) in the central and southern domains (Garraf and Prades), with conglomerates of alluvial fan origin followed by fluvial and aeolian sandstones. Source area of the fluvial sediments was nearby Paleozoic highs to the north and west, in contrast with the far-away source areas of the fluvial sediments in the Iberian Ranges, to the SW. These fluvial systems were interacting with migrating aeolian dune fields located towards the S, which developed in the shadow areas behind the barriers formed by the Paleozoic highs. These highs were separating the subbasins under arid and semi-arid climate conditions. The dominating winds came from the east where the westernmost coast of the Tethys Sea was located, and periods of water run-off and fields of aeolian dunes development alternated. Some of the fluvial systems were probably evaporating as they were mixed into the interdune areas, never reaching the sea. From the end of the Smithian to the Spathian, the Catalan Basin and neighbour peri-Tethys basins of the present-day southern France

  15. Chemotaxis of Escherichia coli to norepinephrine (NE) requires conversion of NE to 3,4-dihydroxymandelic acid.

    PubMed

    Pasupuleti, Sasikiran; Sule, Nitesh; Cohn, William B; MacKenzie, Duncan S; Jayaraman, Arul; Manson, Michael D

    2014-12-01

    Norepinephrine (NE), the primary neurotransmitter of the sympathetic nervous system, has been reported to be a chemoattractant for enterohemorrhagic Escherichia coli (EHEC). Here we show that nonpathogenic E. coli K-12 grown in the presence of 2 μM NE is also attracted to NE. Growth with NE induces transcription of genes encoding the tyramine oxidase, TynA, and the aromatic aldehyde dehydrogenase, FeaB, whose respective activities can, in principle, convert NE to 3,4-dihydroxymandelic acid (DHMA). Our results indicate that the apparent attractant response to NE is in fact chemotaxis to DHMA, which was found to be a strong attractant for E. coli. Only strains of E. coli K-12 that produce TynA and FeaB exhibited an attractant response to NE. We demonstrate that DHMA is sensed by the serine chemoreceptor Tsr and that the chemotaxis response requires an intact serine-binding site. The threshold concentration for detection is ≤5 nM DHMA, and the response is inhibited at DHMA concentrations above 50 μM. Cells producing a heterodimeric Tsr receptor containing only one functional serine-binding site still respond like the wild type to low concentrations of DHMA, but their response persists at higher concentrations. We propose that chemotaxis to DHMA generated from NE by bacteria that have already colonized the intestinal epithelium may recruit E. coli and other enteric bacteria that possess a Tsr-like receptor to preferred sites of infection. PMID:25182492

  16. Sedimentary model for Eocene exotic blocks of carbonates and turbiditic carbonate deposits in the South Sistan Basin, SE Iran

    NASA Astrophysics Data System (ADS)

    Mohammadi, Ali; Burg, Jean-Pierre; Bernoulli, Daniel

    2016-04-01

    The N-S-trending Sistan Suture Zone in east Iran results from collision of the Lut Block to the west with the Afghan Block to the east. Extensive Eocene turbiditic sequences with numerous exotic carbonate olistholiths and carbonate debris flows in the southern part of the Sistan Basin (so-called Neh Accretionary Wedge) were deposited in a deep-marine environment. Litho-biostratigraphy of the exotic carbonate blocks and carbonate debris flows with surrounding sandstones aims to develop a paleoenvironmental model for the South Sistan sedimentary basin. The olistholiths, of Early to Middle Eocene age, are derived from one or more carbonate platforms including inner shelf (protected platform), shelf margin (coral reefs, skeletal sand bars) and upper slope deposits. In addition, the terrigenous turbidites that form the background sediments of the basinal deposits are interlayered with carbonate mass-flow deposits, lime turbidites and scarcer pelagic limestones with planktonic foraminifera of Eocene age showing that the mass-flow events contemporaneous with platform evolution. The absence of terrigenous detritus and of volcanic material in the platform limestones and related mass-flow deposits suggests that the carbonate platform was presumably located on the Kuh-e-Birk passive margin, to the southwest of the Sistan Basin. Key words: South Sistan Basin, sedimentary model, Eocene, olistostrome, carbonate platform

  17. Programmable data collection platform study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The results of a feasibility study incorporating microprocessors in data collection platforms in described. An introduction to microcomputer hardware and software concepts is provided. The influence of microprocessor technology on the design of programmable data collection platform hardware is discussed. A standard modular PDCP design capable of meeting the design goals is proposed, and the process of developing PDCP programs is examined. A description of design and construction of the UT PDCP development system is given.

  18. Patents protect deepwater platform concepts

    SciTech Connect

    Khurana, S.

    1998-06-22

    Numerous deepwater platform concepts have patents that provide an inventor protection for his new ideas. But an inventor should not be discouraged by the fact that many patents exist. In fact, it may be advantageous to build on existing patents and prior art, and patent new ideas and concepts for reducing costs. Challenges still remain such as for optimizing drilling and production operations simultaneously on deepwater platforms for accessing and producing oil and gas reserves.

  19. Ocean Thermal Energy Conversion moored pipe/mobile platform design study

    SciTech Connect

    Bullock, H.O.; McNatt, T.R.; Ross, J.M.; Stambaugh, K.A.; Watts, J.L.

    1982-07-30

    The Ocean Thermal Energy Conversion (OTEC) Moored Pipe/Mobile Platform (MP-Squared) Design Study was carried out to investigate an innovative approach to the moored floating OTEC plant. In the past, a number of concepts have been examined by NOAA for floating OTEC plants. These concepts have considered various configurations for platforms, cold water pipes and mooring systems. In most cases the cold water pipe (CWP) was permanently attached to the platform and the platform was permanently moored on station. Even though CWP concepts incorporating articulated joints or flexible pipes were used, the CWP stresses induced by platform motion were frequently excessive and beyond the design limits of the CWP. This was especially true in the survival (100-year storm) case. It may be feasible that the concept of a permanently moored CWP attached through a flexible transition CWP to the platform could reduce the degree of technical risk by de-coupling the CWP from the motions of the platform. In addition, if the platform is capable of disconnecting from the CWP during survival conditions, even less technical risk may be inherent in the OTEC system. The MP-Squared Design Study was an engineering evaluation of the concepts described above. The effort has been carried through to the conceptual design level, and culminated in model tests in an experimental wave basin.

  20. Studying the NE Eridania sedimentary sequence through the Mars 2020 rover

    NASA Astrophysics Data System (ADS)

    Pajola, M.; Carter, J.; Rossato, S.; Baratti, E.; Mangili, C.; Coradini, M.; McBride, K. S.

    2014-04-01

    The landing sites we are proposing for the next Mars 2020 rover span between 28°29'30"S-28°53'0"S Latitude and 178°56'30"W°178°28'0"W Longitude, i.e. on the NE floor of a 1.1×106 km2 closed drainage basin [1]. This area, see Fig. 1, belongs to the bigger (3×106 km2) Eridania basin that gave birth to the Ma'adim Vallis through catastrophic overflow, and presenting a water table between 950 and 1250 m [1,2,3]. The crater counting chronology for this area gives an age between Early to Middle Noachian [4]. By means of OMEGA [5] and CRISM [6] data, a large clay-bearing sedimentary unit has been identified over almost the entire margin of the Eridania basin [7]. On our specific site, i.e. the NE margin of the Eridania basin, sequences of aqueous minerals are observed. Such sedimentary minerals are accessible through erosional windows into the first several tens of meters of the sedimentary sequence. The top-down mineral sequence identified on the landing sites area presents an unaltered capping unit that is overlying an Al-rich clay stratum (see Fig. 2) akin to Al-smectite and/or kaolins with a <1 m thickness. A third sedimentary Fe-rich clay layer (akin to the nontronite smectite) is found, presenting a thickness of <10 m and overlying a mineral at the base of the exposed strata, which could be either a zeolite (favoured scenario) or a hydrated sulfate. On Earth, the thicknesses and compositions of the clay-rich strata have been used to constrain the paleoclimate [8,9], hence, the in situ exploration of the proposed sedimentary sequences at Eridania would provide fundamental observables of the early era (> 3.8 Ga) during which liquid water was durably stable at the surface. The most valuable candidates for ancient Martian microbial life sustainability and preservation are longlasting environments, characterized by the presence of ponding water [10,11,12]: hence, the proposed site presents a high exobiological potential that is just waiting to be unveiled. Besides

  1. The COMET Sleep Research Platform

    PubMed Central

    Nichols, Deborah A.; DeSalvo, Steven; Miller, Richard A.; Jónsson, Darrell; Griffin, Kara S.; Hyde, Pamela R.; Walsh, James K.; Kushida, Clete A.

    2014-01-01

    Introduction: The Comparative Outcomes Management with Electronic Data Technology (COMET) platform is extensible and designed for facilitating multicenter electronic clinical research. Background: Our research goals were the following: (1) to conduct a comparative effectiveness trial (CET) for two obstructive sleep apnea treatments—positive airway pressure versus oral appliance therapy; and (2) to establish a new electronic network infrastructure that would support this study and other clinical research studies. Discussion: The COMET platform was created to satisfy the needs of CET with a focus on creating a platform that provides comprehensive toolsets, multisite collaboration, and end-to-end data management. The platform also provides medical researchers the ability to visualize and interpret data using business intelligence (BI) tools. Conclusion: COMET is a research platform that is scalable and extensible, and which, in a future version, can accommodate big data sets and enable efficient and effective research across multiple studies and medical specialties. The COMET platform components were designed for an eventual move to a cloud computing infrastructure that enhances sustainability, overall cost effectiveness, and return on investment. PMID:25848590

  2. Mapping the geophysical bedrock of the Moesian Platform using H/V ratios and borehole data.

    NASA Astrophysics Data System (ADS)

    Florinela Manea, Elena; Michel, Clotaire; Fäh, Donat; Ortanza Cioflan, Carmen

    2016-04-01

    The strong effects at long periods observed in the extra-Carpathian area of Romania during large Vrancea intermediate-depth earthquakes were explained by the influence of both source mechanism and mechanical properties of the geological structure. Complex basin geometry and the low seismic velocities of the sediments are the primary responsible for the large amplification and long duration of the seismic records from the extra-Carpathian area during intermediate-depth earthquakes. The aim of this study is to map the geophysical bedrock of this area correlating and interpolating the results obtained from local resonance phenomena evaluation with the available surface geological data. The site was investigated through the computation of H/V spectral ratios from three-directional single station measurements of ambient vibration. The first step was to estimate the depth of the geophysical bedrock at all the Romanian seismic stations located in the extra-Carpathian area (velocity sensors) using the fundamental frequency retrieved from the H/V curves. In the second stage of the study all the relevant peaks from the H/V curves were interpreted in consonance with the available information of the geology. The geological data were obtained from the database developed in the national BIGSEES project by National Institute of Earth Physics. In this database are integrated all the geological, geophysical data from all the past projects, contracts, studies (as refraction, reflexion, etc.), geotechnical drillings and other information publicly available. The mapping of the geophysical bedrock was done interpolating the geological database and information gathered/resulted from H/V using a geographical informational system(GIS). The geology of this area displays very complex features as outcrops in small zones/lines/ near the Danube and then is gradually dipping to about 2 km depth in the N-NE. The depth of the bedrock is (nearly) constant around 100 m depth on the right side of

  3. neXtProt: organizing protein knowledge in the context of human proteome projects.

    PubMed

    Gaudet, Pascale; Argoud-Puy, Ghislaine; Cusin, Isabelle; Duek, Paula; Evalet, Olivier; Gateau, Alain; Gleizes, Anne; Pereira, Mario; Zahn-Zabal, Monique; Zwahlen, Catherine; Bairoch, Amos; Lane, Lydie

    2013-01-01

    About 5000 (25%) of the ~20400 human protein-coding genes currently lack any experimental evidence at the protein level. For many others, there is only little information relative to their abundance, distribution, subcellular localization, interactions, or cellular functions. The aim of the HUPO Human Proteome Project (HPP, www.thehpp.org ) is to collect this information for every human protein. HPP is based on three major pillars: mass spectrometry (MS), antibody/affinity capture reagents (Ab), and bioinformatics-driven knowledge base (KB). To meet this objective, the Chromosome-Centric Human Proteome Project (C-HPP) proposes to build this catalog chromosome-by-chromosome ( www.c-hpp.org ) by focusing primarily on proteins that currently lack MS evidence or Ab detection. These are termed "missing proteins" by the HPP consortium. The lack of observation of a protein can be due to various factors including incorrect and incomplete gene annotation, low or restricted expression, or instability. neXtProt ( www.nextprot.org ) is a new web-based knowledge platform specific for human proteins that aims to complement UniProtKB/Swiss-Prot ( www.uniprot.org ) with detailed information obtained from carefully selected high-throughput experiments on genomic variation, post-translational modifications, as well as protein expression in tissues and cells. This article describes how neXtProt contributes to prioritize C-HPP efforts and integrates C-HPP results with other research efforts to create a complete human proteome catalog. PMID:23205526

  4. Feasibility study of heavy oil recovery in the Permian Basin (Texas and New Mexico)

    SciTech Connect

    Olsen, D.K.; Johnson, W.I.

    1993-05-01

    This report is one of a series of publications assessing the feasibility of increasing domestic heavy oil production. Each report covers select areas of the United States. The Permian Basin of West Texas and Southeastern New Mexico is made up of the Midland, Delaware, Val Verde, and Kerr Basins; the Northwestern, Eastern, and Southern shelves; the Central Basin Platform, and the Sheffield Channel. The present day Permian Basin was one sedimentary basin until uplift and subsidence occurred during Pennsylvanian and early Permian Age to create the configuration of the basins, shelves, and platform of today. The basin has been a major light oil producing area served by an extensive pipeline network connected to refineries designed to process light sweet and limited sour crude oil. Limited resources of heavy oil (10`` to 20`` API gravity) occurs in both carbonate and sandstone reservoirs of Permian and Cretaceous Age. The largest cumulative heavy oil production comes from fluvial sandstones of the Cretaceous Trinity Group. Permian heavy oil is principally paraffinic and thus commands a higher price than asphaltic California heavy oil. Heavy oil in deeper reservoirs has solution gas and low viscosity and thus can be produced by primary and by waterflooding. Because of the nature of the resource, the Permian Basin should not be considered a major heavy oil producing area.

  5. Feasibility study of heavy oil recovery in the Permian Basin (Texas and New Mexico)

    SciTech Connect

    Olsen, D.K.; Johnson, W.I.

    1993-05-01

    This report is one of a series of publications assessing the feasibility of increasing domestic heavy oil production. Each report covers select areas of the United States. The Permian Basin of West Texas and Southeastern New Mexico is made up of the Midland, Delaware, Val Verde, and Kerr Basins; the Northwestern, Eastern, and Southern shelves; the Central Basin Platform, and the Sheffield Channel. The present day Permian Basin was one sedimentary basin until uplift and subsidence occurred during Pennsylvanian and early Permian Age to create the configuration of the basins, shelves, and platform of today. The basin has been a major light oil producing area served by an extensive pipeline network connected to refineries designed to process light sweet and limited sour crude oil. Limited resources of heavy oil (10'' to 20'' API gravity) occurs in both carbonate and sandstone reservoirs of Permian and Cretaceous Age. The largest cumulative heavy oil production comes from fluvial sandstones of the Cretaceous Trinity Group. Permian heavy oil is principally paraffinic and thus commands a higher price than asphaltic California heavy oil. Heavy oil in deeper reservoirs has solution gas and low viscosity and thus can be produced by primary and by waterflooding. Because of the nature of the resource, the Permian Basin should not be considered a major heavy oil producing area.

  6. Observations of interstellar Ne at 1 AU

    NASA Astrophysics Data System (ADS)

    Drews, Christian; Berger, Lars; Wimmer-Schweingruber, Robert F.; Galvin, Antoinette B.; Klecker, Berndt; Möbius, Eberhard

    2010-05-01

    as interstellar helium and neon using STEREO PLASTIC's Pulse Height Analysis data. We have investigated long time series of pickup count rates between 2007 and 2009 of He+, C+, and O+ which show a significant formation of the focusing cone for the interstellar component of pickup ions. In agreement with theoretical expectations focusing of inner-source PUIs, i.e. C+ and O+, is not observed. By comparing mass-per-charge spectra inside and outside the cone, we have succeeded in distinguishing interstellar from inner-source Ne+ pickup ions. This constitutes the first discovery of interstellar Ne at 1 AU.

  7. 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.

  8. Positive nonlinear pressure shift of Cs in Ne

    NASA Astrophysics Data System (ADS)

    Xia, Tian; McGuyer, Bart; Jau, Yuan-Yu; Happer, William

    2010-03-01

    We demonstrate that the hyperfine resonance frequency of ground state Cs atoms have a nonlinear dependence on the pressure of the buffer gas Ne at a fixed temperature. The hyperfine resonance frequency of alkali-metal atoms is shifted by an amount, which had long been assumed to be linear with the buffer gas pressure until Fei Gong discovered that the shift of Rb and Cs hyperfine resonance frequency has a nonlinear dependence on the pressure of the buffer gas Ar and Kr. While the nonlinear pressure shift of Cs in Ar and Kr is negative, we found that the nonlinear pressure shift of Cs hyperfine frequency in Ne is positive. The reason of the nonlinear shift is the three body collision(eg: Cs-Ne-Ne) and the formation of Van der Waals molecules of a Cs atom and a buffer gas atom of Ar, Kr, or Ne. The hyperfine precession rate of a Cs atom bound in molecule has a shift respect to a free Cs atom. The reversal sign of this nonlinear pressure shift of Cs in Ne respect to Ar and Kr demonstrate that the shift of the hyperfine precession rate of Cs in CsNe is reversed respect to CsAr and CsKr.

  9. Scattering study of the Ne + NeH+(v0 = 0, j0 = 0) → NeH+ + Ne reaction on an ab initio based analytical potential energy surface

    NASA Astrophysics Data System (ADS)

    Koner, Debasish; Barrios, Lizandra; González-Lezana, Tomás; Panda, Aditya N.

    2016-01-01

    Initial state selected dynamics of the Ne + NeH+(v0 = 0, j0 = 0) → NeH+ + Ne reaction is investigated by quantum and statistical quantum mechanical (SQM) methods on the ground electronic state. The three-body ab initio energies on a set of suitably chosen grid points have been computed at CCSD(T)/aug-cc-PVQZ level and analytically fitted. The fitting of the diatomic potentials, computed at the same level of theory, is performed by spline interpolation. A collinear [NeHNe]+ structure lying 0.72 eV below the Ne + NeH+ asymptote is found to be the most stable geometry for this system. Energies of low lying vibrational states have been computed for this stable complex. Reaction probabilities obtained from quantum calculations exhibit dense oscillatory structures, particularly in the low energy region and these get partially washed out in the integral cross section results. SQM predictions are devoid of oscillatory structures and remain close to 0.5 after the rise at the threshold thus giving a crude average description of the quantum probabilities. Statistical cross sections and rate constants are nevertheless in sufficiently good agreement with the quantum results to suggest an important role of a complex-forming dynamics for the title reaction.

  10. Sequence stratigraphy of the Jurassic-Cretaceous Morrison and Cedar Mountain Formations, NE Utah--NW Colorado

    SciTech Connect

    Currie, B.S. . Dept. of Geological Sciences)

    1993-04-01

    The Jurassic-Cretaceous Morrison and Cedar Mountain of NE Utah and NW Colorado record nonmarine deposition during early development of the Cordilleran foreland basin. Contained within these formations are three distinct depositional sequences that represent changes in sedimentary architecture due to fluctuations in development of basin accommodation. The first of these sequences comprises the Oxfordian transition from marine to nonmarine sedimentation. Morrison Formation marginal marine and nonmarine facies prograded across shallow marine facies of the Stump Formation (Redwater Member), during a period of increased accommodation. The base of the second depositional sequences within the Morrison Formation was produced by a decrease in regional accommodation. The Cretaceous Cedar Mountain Formation unconformably overlies the Morrison Formation and its base marks the lower boundary of the third depositional sequence. The unconformity surface represents a decrease in regional accommodation and is marked by fluvial incision and evidence of subaerial exposure and intense weathering of the upper Brushy Basin Member. Increased basin accommodation during the early Cretaceous (Aptian-Albian ) resulted in valley fill deposition of the braided fluvial Buckhorn Conglomerate Member of the Cedar Mountain Formation. This conglomerate is overlain by Cedar Mountain anastomosing fluvial and lacustrine facies which were deposited during continued accommodation development. The Sequence is capped unconformity by the Albian-Cenomanian Dakota Formation.

  11. Evidence for the Permo-Triassic transtensional rifting in the Iberian Range (NE Spain) according to magnetic fabrics results

    NASA Astrophysics Data System (ADS)

    García-Lasanta, C.; Oliva-Urcia, B.; Román-Berdiel, T.; Casas, A. M.; Gil-Peña, I.; Sánchez-Moya, Y.; Sopeña, A.; Hirt, A. M.; Mattei, M.

    2015-05-01

    Anisotropy of magnetic susceptibility (AMS) techniques are applied to Permo-Triassic red beds from the Castilian Branch (Iberian Range, NE Spain) that were deposited in an extensional basin inverted during Cenozoic times. The main goal of this work is to characterize the tectonic evolution of the basinal stage by differentiating synsedimentary to early diagenetic magnetic fabrics from the secondary tectonic fabrics related to compression, which are scarcely developed because no penetrative structures related to compression have been recognized. Oblate magnetic fabrics, with kmin axes perpendicular to bedding ,are observed in most cases. Magnetic lineations are variable, showing a dominant ENE-WSW maximum, which fits with a dextral transtensional regime acting on NW-SE master faults during the Triassic. We propose that variations in the orientation of the magnetic lineation are associated with transfer faults which fragment the basin and trigger strain partitioning in different areas. Magnetic fabrics are locally modified by Cenozoic compression, with intermediate and minimum axes distributed along girdles perpendicular to fold axes. Comparing all these results with macrostructures and mesostructural kinematic indicators, we conclude that the fine-grained hematite-bearing rocks carry a consistent magnetic fabric which can be used to reconstruct the basin history.

  12. Pedogeochemistry in NE-Brazil - compared to Australia and Europe.

    PubMed

    Schucknecht, Anne; Matschullat, Jörg; de Caritat, Patrice; da Silva, Juscimar; Melo, Germano; Pleßow, Alexander; Mello, Jaime W V

    2012-11-01

    A soil geochemical dataset (major and minor elements), based on low-density sampling, is provided for NE-Brazil (ca. 1.7 million km²). It covers an area from about 2°S to 12°S, and from 34°W to 49°W, and refers to top (TOP: 0-20 cm) and bottom (BOT: 30-50 cm) mineral soils. Results are put in perspective using two recent and comparable studies, the National Geochemical Survey of Australia (NGSA) and the European Geochemical Mapping of Agricultural Soils (GEMAS). All median element concentrations in the Brazilian samples are depleted compared to World Soil Averages (WSA), except for Al₂O₃ and SiO₂, which are respectively similar to WSA and enriched in Brazil. While the depletion is moderate for Fe₂O₃, MnO, P₂O₅, and TiO₂, it reaches an order of magnitude and more for K₂O, MgO, CaO, and Na₂O. The difference between TOP and BOT concentrations is lower than the variation of either TOP or BOT concentrations between sample sites. Similar spatial distribution and the high correlation between TOP and BOT concentrations suggest that (1) similar processes and parameters are of general relevance for the geochemical composition of TOP and BOT samples, and (2) topsoil and subsoil are not decoupled. Cluster analysis revealed similar results for TOP and BOT samples, yielding three groups of elements/oxides displaying similar behavior: Gr.1 comprising Al₂O₃, Fe₂O₃, TiO₂, and P₂O₅; Gr.2 comprising CaO, K₂O, MgO, MnO, and Na₂O; and Gr.3 being SiO₂. Weathering indicators are significantly positively correlated and show similar spatial distributions in TOP and BOT samples. All elements deliver similar mass removal times (time to export all material from a 10 cm soil layer) and clearly discern between the regions: Europe with the fastest "depletion" (12,200 ± 300 years), followed by Australia (33,200 ± 3000 years) and Brazil (86,700 ± 3000 years). Similar results emerge when calculating denudation rates, using independent fluvial

  13. Structural evolution and facies development on the Florida-Bahama Platform--Triassic through Paleocene

    SciTech Connect

    Winston, G.O.

    1993-03-01

    The Florida-Bahama Platform encompasses all of Florida on and offshore, the Blake Plateau, Great and Little Bahama Banks including channels and straits, and northern Cuba. During the Upper Jurassic-Coahuilan, a Northwestern Sedimentary Province contained the Middle Ground Arch separating the Tampa Basin from the DeSoto Salt Basin to the north. A Southeastern Sedimentary Province was separated from the Northwestern Province by the Sarasota and Peninsular Arches. During the Comanchean, the Southeastern Province developed into the South Florida, Bahama and Blake Plateau Basins, separated respectively by the Cay Sal Arch and the Little Bahama High. From the Upper Jurassic through the Comanchean, the continental margin of the Platform was occupied by a carbonate complex that restricted marine circulation in much of the area. In the Southeastern Sedimentary Province, this barrier caused the deposition of lagoonal carbonates and anhydrites. Deposition of these rock types ended at the close of the Comanchean with the break-up of the Florida-Bahama Platform and the destruction of the carbonate complex. Early in the Gulfian, the rapid subsidence of the Blake Plateau Basin to bathyal depths and the collapse of the Florida Straits accompanies tectonic activity in Cuba. Also in the Early Gulfian, the Rebecca Shoal barrier reef appeared on the upthrown northern side of the Straits. By the end of the Gulfian the reef had expanded to encircle the Florida peninsula, causing deposition of the Cedar Keys (Paleocene) lagoonal dolomite and anhydrite.

  14. Atmospheric noble gas signatures in deep Michigan Basin brines as indicators of a past thermal event

    NASA Astrophysics Data System (ADS)

    Ma, Lin; Castro, Maria Clara; Hall, Chris M.

    2009-01-01

    Atmospheric noble gases (e.g., 22Ne, 36Ar, 84Kr, 130Xe) in crustal fluids are only sensitive to subsurface physical processes. In particular, depletion of atmospheric noble gases in groundwater due to boiling and steam separation is indicative of the occurrence of a thermal event and can thus be used to trace the thermal history of stable tectonic regions. We present noble gas concentrations of 38 deep brines (~ 0.5-3.6 km) from the Michigan Basin. The atmospheric noble gas component shows a strong depletion pattern with respect to air saturated water. Depletion of lighter gases ( 22Ne and 36Ar) is stronger compared to the heavier ones ( 84Kr and 130Xe). To understand the mechanisms responsible for this overall atmospheric noble gas depletion, phase interaction models were tested. We show that this atmospheric noble gas depletion pattern is best explained by a model involving subsurface boiling and steam separation, and thus, consistent with the occurrence of a past thermal event of mantle origin as previously indicated by both high 4He/heat flux ratios and the presence of primordial mantle He and Ne signatures in the basin. Such a conceptual model is also consistent with the presence of past elevated temperatures in the Michigan Basin (e.g., ~ 80-260 °C) at shallow depths as suggested by previous thermal studies in the basin. We suggest that recent reactivation of the ancient mid-continent rift system underneath the Michigan Basin is likely responsible for the release of both heat and mantle noble gases into the basin via deep-seated faults and fracture zones. Relative enrichment of atmospheric Kr and Xe with respect to Ar is also observed, and is interpreted as reflecting the addition of sedimentary Kr and Xe from associated hydrocarbons, following the hydrothermal event. This study pioneers the use of atmospheric noble gases in subsurface fluids to trace the thermal history of stable tectonic regions.

  15. Pion inelastic scattering from sup 20 Ne

    SciTech Connect

    Burlein, M. . Dept. of Physics)

    1989-12-01

    Angular distributions for {sup 20}Ne({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime}) were measured on the Energetic Pion Channel and Spectrometer (EPICS) at the Clinton P. Anderson Meson Physics Facility (LAMPF). Data were taken with both {pi}{sup {plus}} and {pi}{sup {minus}} over an angular range of 12{degree} to 90{degree} for T{sub {pi}}=180 MeV and with {pi}{sup +} from 15{degree} to 90{degree} for T{sub {pi}}=120 MeV. The data were analyzed using both the distorted-wave impulse approximation (DWIA) and the coupled-channels impulse approximation (CCIA) with collective transition densities. In addition, microscopic transition densities were used in the DWIA analysis for states in the lowest rotational bands. The transitions to the 6.73-MeV 0{sup +} and several 1{sup {minus}} states, including the states at 5.79 MeV and 8.71 MeV, were studied using several models for the transition density. Strong evidence for the importance of two-step routes in pion inelastic scattering was seen in several angular distributions, including the 5.79-MeV 1{sup {minus}}, the first three 4{sup +} states, and the 8.78-MeV 6{sup +}. 100 refs., 81 figs., 33 tabs.

  16. MiniBooNE liner integrity study

    SciTech Connect

    Ray Stefanski, Phil Martin and Jeff Sims

    2001-11-09

    The civil construction for the MiniBooNE project includes a 50-m decay path and beam absorbers. The decay path is a six-foot diameter corrugated metal pipe (CMP). To prevent activation of the groundwater, the CMP and beam absorbers are surrounded by crushed aggregate, and enclosed in a double-walled geotextile membrane, referred to as the liner. The minimum distance from the beam centerline to the liner is 10 feet. The double-wall construction of the liner forms three regions, the containment volume, the interstitial volume, and the exterior. Each of these volumes is connected to monitoring wells at both the upstream and downstream ends of the decay volume, i.e. a total of six monitoring pipes extend to the surface. To confirm the integrity of the liner system following its placement, the firm Earth Tech was contracted to perform tests. Michael Williams was the primary contact with Earth Tech. The following is the report from Earth Tech, with minor changes in the interest of clarity. A sketch of the decay region is shown; only one of the layers of the liner is shown, and only one monitoring port. At the time of these tests, the excavation in general, but particularly in the vicinity of the monitoring wells had not been backfilled in the final grade, as indicated by the dashed lines.

  17. Exclusive measurements of nuclear breakup reactions of 17Ne

    NASA Astrophysics Data System (ADS)

    Wamers, F.; Marganiec, J.; Aksouh, F.; Aksyutina, Yu.; Álvarez-Pol, H.; Aumann, T.; Beceiro-Novo, S.; Bertulani, C. A.; Boretzky, K.; Borge, M. J. G.; Chartier, M.; Chatillon, A.; Chulkov, L. V.; Cortina-Gil, D.; Egorova, I. A.; Emling, H.; Ershova, O.; Forssén, C.; Fraile, L. M.; Fynbo, H.; Galaviz, D.; Geissel, H.; Grigorenko, L. V.; Heil, M.; Hoffmann, D. H. H.; Hoffmann, J.; Johansson, H.; Jonson, B.; Karagiannis, C.; Karakoç, M.; Kiselev, O. A.; Kratz, J. V.; Kulessa, R.; Kurz, N.; Langer, C.; Lantz, M.; Larsson, K.; Le Bleis, T.; Lemmon, R.; Litvinov, Yu. A.; Mahata, K.; Müntz, C.; Nilsson, T.; Nociforo, C.; Nyman, G.; Ott, W.; Panin, V.; Parfenova, Yu. L.; Paschalis, S.; Perea, A.; Plag, R.; Reifarth, R.; Richter, A.; Rodriguez-Tajes, C.; Rossi, D.; Riisager, K.; Savran, D.; Schrieder, G.; Shul'gina, N. B.; Simon, H.; Stroth, J.; Sümmerer, K.; Taylor, J.; Tengblad, O.; Tengborn, E.; Weick, H.; Wimmer, C.; Zhukov, M. V.

    2014-03-01

    We have studied one-proton-removal reactions of about 500MeV/u 17Ne beams on a carbon target at the R3B/LAND setup at GSI by detecting beam-like 15O-p and determining their relative-energy distribution. We exclusively selected the removal of a 17Ne halo proton, and the Glauber-model analysis of the 16F momentum distribution resulted in an s2 contribution in the 17Ne ground state of about 40%.

  18. Reconstructing the cosmogenic 21Ne inventory of Neogene sedimentary sequences

    NASA Astrophysics Data System (ADS)

    Stuart, Finlay; Sinclair, Hugh; McCann, Louise

    2016-04-01

    The cosmogenic radionuclides, in particular 10Be, have found use in modern sediments as a way of determining the erosion rate of river catchments. Cosmogenic 21Ne in quartz is easier and faster to measure than 10Be and has the potential to record erosion rates back 10s million years. However the routine use of cosmogenic 21Ne in quartz sand is hampered by ubiquitous nucleogenic 21Ne. When the eroding lithology can be identified it is possible to measure the nucleogenic in samples that are shielded from cosmic rays and correct for it in exposed bedrock [1]. However, identifying the lithologies that contributes quartz sand in large river catchments, and determining precise nucleogenic contributions is more problematic. The North and South Platte rivers drain early Prototerozoic lithologies of the Laramie and Front Ranges in the high Rockies of Wyoming. They have deposited several km of coarse clastic fluvial deposits on the Great Plains of Nebraska and Colorado up to 200 km from the mountain front. Quartz from shielded samples of granite and gneiss - the dominant quartz-bearing rocks - has high concentrations of nucleogenic 21Ne (60-140 e6 atoms/g). The 21Ne concentration in modern sand from the river (n=10) overlaps that measured in the shielded granite and gneiss. The sand data rarely lie on the air-spallation mixing line in the Ne three isotope plot indicating that it is dominantly derived from the granite and gneiss and has no resolvable cosmogenic 21Ne. Building on previous studies of cosmogenic 21Ne in pebbles [2] we have started a programme of analysis of pebbles derived from the Medicine Bow quartzite that are abundant throughout the Cenozoic alluvial sequence. Nucleogenic 21Ne in shielded quartzite is lower than granites (3-7 e6 atoms/g, n=4) and the data tend to lie on the air-spallation mixing line. All pebbles (n=14) from modern sediments analysed so far contain 2-80 times more excess 21Ne than the highest shielded quartzite suggesting that cosmogenic 21

  19. Evolution and palaeoenvironment of the Bauru Basin (Upper Cretaceous, Brazil)

    NASA Astrophysics Data System (ADS)

    Fernandes, Luiz Alberto; Magalhães Ribeiro, Claudia Maria

    2015-08-01

    The Bauru Basin was one of the great Cretaceous desert basins of the world, evolved in arid zone called Southern Hot Arid Belt. Its paleobiological record consists mainly of dinosaurs, crocodiles and turtles. The Bauru Basin is an extensive region of the South American continent that includes parts of the southeast and south of Brazil, covering an area of 370,000 km2. It is an interior continental basin that developed as a result of subsidence of the central-southern part of the South-American Platform during the Late Cretaceous (Coniacian-Maastrichtian). This sag basin is filled by a sandy siliciclastic sequence with a preserved maximum thickness of 480 m, deposited in semiarid to desert conditions. Its basement consists of volcanic rocks (mainly basalts) of the Lower Cretaceous (Hauterivian) Serra Geral basalt flows, of the Paraná-Etendeka Continental Flood Basalt Province. The sag basin was filled by an essentially siliciclastic psammitic sequence. In lithostratigraphic terms the sequence consists of the Caiuá and Bauru groups. The northern and northeastern edges of the basin provide a record of more proximal original deposits, such as associations of conglomeratic sand facies from alluvial fans, lakes, and intertwined distributary river systems. The progressive basin filling led to the burial of the basaltic substrate by extensive blanket sand sheets, associated with deposits of small dunes and small shallow lakes that retained mud (such as loess). Also in this intermediate context between the edges (more humid) and the interior (dry), wide sand sheet areas crossed by unconfined desert rivers (wadis) occurred. In the central axis of the elliptical basin a regional drainage system formed, flowing from northeast to southwest between the edges of the basin and the hot and dry inner periphery of the Caiuá desert (southwest). Life in the Bauru Basin flourished most in the areas with the greatest water availability, in which dinosaurs, crocodiles, turtles, fish

  20. Platform Management System (PMS) evolution

    NASA Technical Reports Server (NTRS)

    Tilley, Mike; Hartley, Jonathan

    1990-01-01

    In fiscal year 1988 a study was begun to define the platform management system (PMS) functions required for the mature platform operations era. The objectives of the task include: (1) defining how to increase the operational productivity of the platform by providing enhanced capability for responding to changing events, (2) influencing the initial PMS design by identifying required 'hooks and scars', and (3) evaluation potential automation techniques that are appropriate given predicted onboard computing resources. Initial platform operations scenarios were defined. The focus was on PMS-related functions where operations enhancements are likely to occur. Operations productivity was defined in terms of scientific productivity of the platform as well as the level of automation of the ground system. The Platform Operations Productivity Enhancement Report was completed earlier this year documenting system enhancements to increase science productivity and ground system automation. Using the baseline PMS defined in the PMS Definition Document as a starting point, the resulting PMS-specific enhancements were molded into a sequence of progressively more sophisticated operations management capabilities. This sequence of upgrades to the PMS has been documented in a PMS Evolution Plan. The plan includes enhancements in the areas of resources scheduling, resource modeling, system and payload anomaly management, and transaction sequence interpretation. A plan for migration of functions from the ground portion of the PMS to the flight portion is also included. The impacts of this plan on the platform are now being documented to ensure that the required 'hooks and scars' are included in the baseline system. Future plans include a prototype of some of the PMS enhancements to address the feasibility of and techniques for implementing these enhancements in the onboard computing environment.

  1. Evolutionary sequences and hydrocarbon potential of Kenya sedimentary basins

    SciTech Connect

    Cregg, A.K. )

    1991-03-01

    Kenya basins have evolved primarily through extension related to episodic continental rifting. In eastern Kenya, thick accumulations of sediments formed within grabens during the prerift phase (Precambrian to Carboniferous) of the Gondwana breakup. Synrift sedimentation (Late Carboniferous to Middle Jurassic) occurred within a north-south rift system, which included the Mandera basin, South Anza basin, and Lamu embayment. During the Early Jurassic, a marine transgression invaded the margins of the eastern Kenya rift basins, resulting in the deposition of platform carbonates and shales. A Callovian-aged salt basin formed in the offshore regions of the Lamu embayment. Intermittent tectonic activity and eustatic sea-level changes controlled sedimentation, which produced marine shales, carbonates or evaporites, and fluvio-deltaic to lacustrine sandstones. From the Early Cretaceous to recent, continental sediments were deposited within the North Anza and Turkana basins. These fluvial-lacustrine sediments are similar to the Lower Cretaceous sequences that have produced oil in the Mesozoic Sudanese Abu Gabra rift. Although exploration activities began in the early 1950s, significant occurrences of potential reservoir, source, and seal lithologies as well as trapping configurations remain in many areas. Favorable structures and sequences of reservoir sandstones and carbonates overlain by potentially sealing lacustrine or marine shales, evaporites, or volcanics have been noted. Potential source beds are believed to be present within shales of the lacustrine or marine depositional environments.

  2. The 20Ne(d,p)21Ne transfer reaction in relation to the s-process abundances

    NASA Astrophysics Data System (ADS)

    Nsangu, C. T.; Laird, A. M.; Parikh, A.; Adsley, P.; Birch, M. D.; Chen, A. A.; Faestermann, T.; Fox, S. P.; Fulton, B. R.; Hertenberger, R.; Irvine, D.; Kay, B. P.; Longland, R.; Manwell, S.; Murphy, A. St. J.; Schmitt, K.; de Séréville, N.; Tomlinson, J. R.; Wirth, H.-F.

    2016-01-01

    A study of the 20Ne(d,p)21Ne transfer reaction was performed using the Quadrupole Dipole Dipole Dipole (Q3D) magnetic spectrograph in Garching, Germany. The experiment probed excitation energies in 21Ne ranging from 6.9 MeV to 8.5 MeV. The aim was to investigate the spectroscopic information of 21Ne within the Gamow window of core helium burning in massive stars. Further information in this region will help reduce the uncertainties on the extrapolation down to Gamow window cross sections of the 17O(α,γ)21Ne reaction. In low metallicity stars, this reaction has a direct impact on s-process abundances by determining the fate of 16O as either a neutron poison or a neutron absorber. The experiment used a 22-MeV deuteron beam, with intensities varying from 0.5-1 μA, and an implanted target of 20Ne of 7 μg/cm2 in 40 μg/cm2 carbon foils. Sixteen 21Ne peaks have been identified in the Ex = 6.9-8.5 MeV range, of which only thirteen peaks correspond to known states. Only the previously-known Ex = 7.960 MeV state was observed within the Gamow window.

  3. Noble Gas Signatures in Antrim Shale Gas in the Michigan Basin - Assessing Compositional Variability and Transport Processes

    NASA Astrophysics Data System (ADS)

    Wen, T.; Castro, M. C.; Ellis, B. R.; Hall, C. M.; Lohmann, K. C.; Bouvier, L.

    2014-12-01

    Recent studies in the Michigan Basin looked at the atmospheric and terrigenic noble gas signatures of deep brines to place constraints on the past thermal history of the basin and to assess the extent of vertical transport processes within this sedimentary system. In this contribution, we present noble gas data of shale gas samples from the Antrim shale formation in the Michigan Basin. The Antrim shale was one of the first economic shale-gas plays in the U.S. and has been actively developed since the 1980's. This study pioneers the use of noble gases in subsurface shale gas in the Michigan Basin to clarify the nature of vertical transport processes within the sedimentary sequence and to assess potential variability of noble gas signatures in shales. Antrim Shale gas samples were analyzed for all stable noble gases (He, Ne, Ar, Kr, Xe) from samples collected at depths between 300 and 500m. Preliminary results show R/Ra values (where R and Ra are the measured and atmospheric 3He/4He ratios, respectively) varying from 0.022 to 0.21. Although most samples fall within typical crustal R/Ra range values (~0.02-0.05), a few samples point to the presence of a mantle He component with higher R/Ra ratios. Samples with higher R/Ra values also display higher 20Ne/22Ne ratios, up to 10.4, and further point to the presence of mantle 20Ne. The presence of crustally produced nucleogenic 21Ne and radiogenic 40Ar is also apparent with 21Ne/22Ne ratios up to 0.033 and 40Ar/36Ar ratios up to 312. The presence of crustally produced 4He, 21Ne and 40Ar is not spatially homogeneous within the Antrim shale. Areas of higher crustal 4He production appear distinct to those of crustally produced 21Ne and 40Ar and are possibly related the presence of different production levels within the shale with varying concentrations of parent elements.

  4. Crustal structure of the NE Rockall Trough from wide-angle seismic data modeling

    NASA Astrophysics Data System (ADS)

    KlingelhöFer, F.; Edwards, R. A.; Hobbs, R. W.; England, R. W.

    2005-11-01

    Two wide-angle seismic lines located in the northern Rockall Trough were acquired in May 2000. One line (line E) crosses the trough from the continental shelf off Lewis to normal oceanic crust west of Lousy Bank in NW-SE direction. The other line (line D) intersects with line E, crosses the Wyville-Thomson Ridge in a SW-NE direction and ends in the Faeroe-Shetland Basin. Sonobuoy data and expanding spread profiles acquired in the same area have been remodeled. Analysis of the seismic data using travel times and amplitudes reveals an up to 5 km thick sedimentary basin including an up to 1.5 km thick basaltic layer which is present in most of the trough. Further conclusions of this study are that the Rockall Trough is underlain by highly stretched continental crust of ˜13 km thickness. The crust thickens to ˜24 km beneath Lousy Bank, which is interpreted to be of continental nature. Beneath the Hebrides continental shelf a three-layer continental crust of 26 km is modeled. An up to 12 km thick high-velocity layer is observed underneath the ocean-continent boundary and is interpreted as magmatic underplating resulting from excess volcanism during rifting. No evidence for an underplate layer could be distinguished beneath the trough area. Modeling of the structure of the Wyville-Thomson Ridge revealed no existing igneous core of the ridge confirming existing theories, that it is a compressional structure.

  5. Geochronology of granitic rocks from the Ruangwa region, southern Tanzania - Links with NE Mozambique and beyond

    NASA Astrophysics Data System (ADS)

    Thomas, Robert J.; Bushi, Alphonce M.; Roberts, Nick M. W.; Jacobs, Joachim

    2014-12-01

    New U-Pb zircon LA-ICP-MS data are presented for 4 granitoid bodies which intrude high grade gneisses of the previously unmapped Ruangwa region in southern Tanzania. The study area forms part of the late Neoproterozoic East African Orogen (EAO). The oldest unit, a coarse-grained migmatitic granitic orthogneiss gave an early Neoproterozoic (Tonian) crystallization age of 899 ± 9/16 Ma, which is similar to, but significantly younger than, Stenian-Tonian basement ages in areas relatively nearby. Crust of this age may extend as far north as the major Phanerozoic Selous Basin, north of which Archaean protolith ages predominate (the "Western Granulites"), except for the juvenile Neoproterozoic "Eastern Granulites", which are not represented in the study area. To the south, the Tonian crust of the study area provides a tentative link with the Marrupa Complex in NE Mozambique. A granite pluton, dated at 650 ± 5/11 Ma is broadly coeval with the main Pan-African tectono-thermal event in the East African Orogen that is recorded across Tanzania north of the Selous Basin. Zircons in this granite contain inherited cores at ca. 770 Ma. This age is within the range of dates obtained from south and west of the study area from juvenile granitoid orthogneisses which might be related to a widespread, but poorly understood, early phase of Gondwana assembly along an Andean-type margin. South of the study area, in NE Mozambique, the latest orogenic events occurred at ca. 550 Ma, and are sometimes attributed to the Ediacaran-aged "Kuunga Orogeny". While metamorphic dates of this age have been recorded from the EAO north of the Selous Basin, magmatic rocks of this event have not been recognized in Tanzania. The two youngest granitoids of the present study are thus the first 500-600 Ma igneous rocks reported from the region. A weakly deformed very coarse-grained granite pluton was dated at 591 ± 4/10 Ma, while a very late, cross-cutting, undeformed granite dyke gave an intrusive age of

  6. Structure of Charnockitic basement in a part of the Krishna-Godavari basin, Andhra Pradesh, India

    NASA Astrophysics Data System (ADS)

    Siribyina, B.; Murthy, I.; Rama Rao, P.

    2008-12-01

    A regional magnetic survey was carried out over an area of 8000 km2 in Godavari districts of Andhra Pradesh, India, which is covered by the rocks of Eastern Ghat Mobile Belt (EGMB). viz., the Khondalitic series and Charnockites in the northern half and Permian to Mesozoic and Cenozoic sediments in the southern half, and forms a part of the Krishna-Godavari (K-G) basin. The survey brought out a strong NE-SW trending anomaly in the area covered by the rocks of Eastern Ghat Mobile Belt (EGMB), and a mild ENE-WSW trending anomaly in the area covered by the sediments of the Krishna-Godavari (K-G) basin. The NE-SW trending anomaly in the northern half could be attributed to the exposed/near surface Charnockite basement that has come closer to the surface as a result of Eastern Ghat Mobile Belt (EGMB) tectonics. Explanation of the mild ENE-WSW trending anomaly over the sediments of the Krishna-Godavari (K-G) basin required a faulted magnetic basement at depth downthrown towards the south. It is therefore concluded that the Charnockitic basement together with the Khondalite group of rocks which are folded and faulted during the different phases of tectonics of Eastern Ghat Mobile Belt (EGMB) extend into the Krishna-Godavari (K-G) basin and further, were involved in faulting during the phases of formation and sedimentation in the Krishna-Godavari (K-G) basin.

  7. Structure of Charnockitic basement in a part of the Krishna-Godavari basin, Andhra Pradesh, India

    NASA Astrophysics Data System (ADS)

    Siribyina, B.

    2009-05-01

    A regional magnetic survey was carried out over an area of 8000 km2 in Godavari districts of Andhra Pradesh, India, which is covered by the rocks of Eastern Ghat Mobile Belt (EGMB)viz., the Khondalitic series and Charnockites in the northern half and Permian to Mesozoic and Cenozoic sediments in the southern half, and forms a part of the Krishna-Godavari (K-G) basin. The survey brought out a strong NE-SW trending anomaly in the area covered by the rocks of Eastern Ghat Mobile Belt (EGMB), and a mild ENE-WSW trending anomaly in the area covered by the sediments of the Krishna-Godavari (K-G) basin. The NE-SW trending anomaly in the northern half could be attributed to the exposed/near surface Charnockite basement that has come closer to the surface as a result of Eastern Ghat Mobile Belt (EGMB) tectonics. Explanation of the mild ENE-WSW trending anomaly over the sediments of the Krishna-Godavari (K-G) basin required a faulted magnetic basement at depth downthrown towards the south. It is therefore concluded that the Charnockitic basement together with the Khondalite group of rocks which are folded and faulted during the different phases of tectonics of Eastern Ghat Mobile Belt (EGMB) extend into the Krishna-Godavari (K-G) basin and further, were involved in faulting during the phases of formation and sedimentation in the Krishna-Godavari (K-G) basin.

  8. The high abundance ratios of Ne/C and Ne/O in the footpoints of solar flares

    NASA Astrophysics Data System (ADS)

    Shemi, Amotz

    1988-05-01

    Element abundances in the solar chromosphere were deduced from analysis of the gamma ray disk flare of 27 April 1981. Abundances of Ne, Mg, Si and Fe correlated with the local galactic abundance but C and O were 3 to 4 times less apparent. A comparison between the gamma ray and coronal abundances indicated an excess of Ne in the chromosphere. A similar 3-fold reduction in the coronal and solar wind abundances of He, C, N, O, Ne, S and Ar relative to the photosphere was explained by a high first ionization potential (greater than 9 V), keeping these elements in a neutral state in the photosphere and lower chromosphere. Gravitational, magnetic and thermal effects then lead to separation of the elements. A model was developed for a selective ionization process occurring only in the flaring area, at the preflare and impulsive phase. Soft X radiation at 1-3 A could penetrate the photospheric flare's footpoint and ionize the Ne there. In this range of wavelengths the photoionization cross section of C is an order of magnitude smaller than that of Ne, so that there is a region in which C remains neutral. O also remains neutral through the highly efficient charge exchange process with H, which is neutral in this region. Ionized Ne is exposed to vertical acceleration processes, which cause its relative enrichment during a 5 to 30 min. period. The vertical magnetic field structure at the flare's footpoint prevents horizontal diffusion of the upwardly moving ions. According to this model, Ne enrichment will occur mainly in gradual gamma ray flares which also have gradual continuous X radiation. The high Ne/O ratio would be expected in all such flares, while the Ne/C ratio, which is more susceptible to the intensity and duration of the soft X radiation, should vary among flares.

  9. Noachian and Hesperian modification of the original Chryse impact basin topography

    NASA Technical Reports Server (NTRS)

    Stockman, Stephanie; Frey, Herbert

    1994-01-01

    We propose a new center (35.5 W, 32.5 N) and ring assignment for the original Chryse impact basin based on photogeologic mapping and re-examination of the published geology. Noachian features in the Chryse Planitia area are the best indicators of the original ancient multiringed impact structure. While other workers have centered the Chryse impact on the topographic low associated with Hesperian volcanic and fluvial deposits, we suggest that the center of the original Noachian-age excavation cavity was located 800 km farther NE, and the basin topography was significantly modified over time.

  10. Structure and evolution of the NE Atlantic conjugate margins off Norway and Greenland (Invited)

    NASA Astrophysics Data System (ADS)

    Faleide, J.; Planke, S.; Theissen-Krah, S.; Abdelmalak, M.; Zastrozhnov, D.; Tsikalas, F.; Breivik, A. J.; Torsvik, T. H.; Gaina, C.; Schmid, D. W.; Myklebust, R.; Mjelde, R.

    2013-12-01

    The continental margins off Norway and NE Greenland evolved in response to the Cenozoic opening of the NE Atlantic. The margins exhibit a distinct along-margin segmentation reflecting structural inheritance extending back to a complex pre-breakup geological history. The sedimentary basins at the conjugate margins developed as a result of multiple phases of post-Caledonian rifting from Late Paleozoic time to final NE Atlantic breakup at the Paleocene-Eocene transition. The >200 million years of repeated extension caused comprehensive crustal thinning and formation of deep sedimentary basins. The main rift phases span the following time intervals: Late Permian, late Middle Jurassic-earliest Cretaceous, Early-mid Cretaceous and Late Cretaceous-Paleocene. The late Mesozoic-early Cenozoic rifting was related to the northward propagation of North Atlantic sea floor spreading, but also linked to important tectonic events in the Arctic. The pre-drift extension is quantified based on observed geometries of crustal thinning and stretching factors derived from tectonic modeling. The total (cumulative) pre-drift extension amounts to in the order of 300 km which correlates well with estimates from plate reconstructions based on paleomagnetic data. Final lithospheric breakup at the Paleocene-Eocene transition culminated in a 3-6 m.y. period of massive magmatic activity during breakup and onset of early sea-floor spreading, forming a part of the North Atlantic Volcanic Province. At the outer parts of the conjugate margins, the lavas form characteristic seaward dipping reflector sequences and lava deltas that drilling has demonstrated to be subaerially and/or neritically erupted basalts. The continent-ocean transition is usually well defined as a rapid increase of P-wave velocities at mid- to lower-crustal levels. Maximum igneous crustal thickness of about 18 km is found across the outer Vøring Plateau on the Norwegian Margin, and lower-crustal P-wave velocities of up to 7.3 km

  11. Tectono-stratigraphic evolution of the northeastern Pyrenean Foreland Basin

    NASA Astrophysics Data System (ADS)

    Christophoul, Frédéric; Ford, Mary; Grool, Arjan; Géraldine, Rougier; Louis, Hemmer

    2016-04-01

    The Aquitaine basin, on the northern flank of the Pyrenees was subject to intense hydrocarbon exploration until the 1990's, generating a huge dataset that has been under-exploited until now. In the framework of the French Pyramid ANR project this dataset was used, together with new field data, to reconstruct the evolution of this retroforeland basin. This study focuses on the eastern retroforeland, from the Corbières to east to the Toulouse Fault to the west. In terms of age, the main depocentres are however contemporary along the whole eastern basin: 1) From Upper Cretaceous to Paleocene (Campanian to Selandian) the early foreland basin, known as the "Flysch Trough", was filled by a succession of turbidites passing upward into fluvial sediments that prograded axially from the east. 2) From Thanetian to Oligocene, a second cycle started with a deepening upward trend until the Ypresian (inner carbonate platform to mixed open marine) and changed to a shallowing upward succession, passing from open marine sediments, coastal clastic deposits and then to coarse fluvial deposits from Upper Ypresian to Oligocene. Progradation was again initially axial from the east. However, a new south to north fluvial drainage developed from the emerging relief of the Pyrenees to the south. In terms of location and structural style of these depocentres, the salt-free eastern basin (from the Corbières in the east to the Toulouse Fault to the west) reveals a distinctive style to the salt-rich western basin. In eastern foreland (Corbières to Aude Valley), syntectonic depocentres migrated north as a series of wedge-top basins between Late Cretaceous and Late Eocene. The thick-skinned syn-sedimentary foreland structures progressively die out westward. In the western part of the study area (Plantaurel to Petites Pyrenees) stacked depocentres of the same age are preserved in the footwall of the North Pyrenean Frontal thrust recording a slower northward migration associated with a northward